v4.19.13 snapshot.
diff --git a/fs/ecryptfs/Kconfig b/fs/ecryptfs/Kconfig
new file mode 100644
index 0000000..434aa31
--- /dev/null
+++ b/fs/ecryptfs/Kconfig
@@ -0,0 +1,22 @@
+config ECRYPT_FS
+ tristate "eCrypt filesystem layer support"
+ depends on KEYS && CRYPTO && (ENCRYPTED_KEYS || ENCRYPTED_KEYS=n)
+ select CRYPTO_ECB
+ select CRYPTO_CBC
+ select CRYPTO_MD5
+ help
+ Encrypted filesystem that operates on the VFS layer. See
+ <file:Documentation/filesystems/ecryptfs.txt> to learn more about
+ eCryptfs. Userspace components are required and can be
+ obtained from <http://ecryptfs.sf.net>.
+
+ To compile this file system support as a module, choose M here: the
+ module will be called ecryptfs.
+
+config ECRYPT_FS_MESSAGING
+ bool "Enable notifications for userspace key wrap/unwrap"
+ depends on ECRYPT_FS
+ help
+ Enables the /dev/ecryptfs entry for use by ecryptfsd. This allows
+ for userspace to wrap/unwrap file encryption keys by other
+ backends, like OpenSSL.
diff --git a/fs/ecryptfs/Makefile b/fs/ecryptfs/Makefile
new file mode 100644
index 0000000..49678a6
--- /dev/null
+++ b/fs/ecryptfs/Makefile
@@ -0,0 +1,10 @@
+#
+# Makefile for the Linux eCryptfs
+#
+
+obj-$(CONFIG_ECRYPT_FS) += ecryptfs.o
+
+ecryptfs-y := dentry.o file.o inode.o main.o super.o mmap.o read_write.o \
+ crypto.o keystore.o kthread.o debug.o
+
+ecryptfs-$(CONFIG_ECRYPT_FS_MESSAGING) += messaging.o miscdev.o
diff --git a/fs/ecryptfs/crypto.c b/fs/ecryptfs/crypto.c
new file mode 100644
index 0000000..4dd842f
--- /dev/null
+++ b/fs/ecryptfs/crypto.c
@@ -0,0 +1,2132 @@
+/**
+ * eCryptfs: Linux filesystem encryption layer
+ *
+ * Copyright (C) 1997-2004 Erez Zadok
+ * Copyright (C) 2001-2004 Stony Brook University
+ * Copyright (C) 2004-2007 International Business Machines Corp.
+ * Author(s): Michael A. Halcrow <mahalcro@us.ibm.com>
+ * Michael C. Thompson <mcthomps@us.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ */
+
+#include <crypto/hash.h>
+#include <crypto/skcipher.h>
+#include <linux/fs.h>
+#include <linux/mount.h>
+#include <linux/pagemap.h>
+#include <linux/random.h>
+#include <linux/compiler.h>
+#include <linux/key.h>
+#include <linux/namei.h>
+#include <linux/file.h>
+#include <linux/scatterlist.h>
+#include <linux/slab.h>
+#include <asm/unaligned.h>
+#include <linux/kernel.h>
+#include "ecryptfs_kernel.h"
+
+#define DECRYPT 0
+#define ENCRYPT 1
+
+/**
+ * ecryptfs_from_hex
+ * @dst: Buffer to take the bytes from src hex; must be at least of
+ * size (src_size / 2)
+ * @src: Buffer to be converted from a hex string representation to raw value
+ * @dst_size: size of dst buffer, or number of hex characters pairs to convert
+ */
+void ecryptfs_from_hex(char *dst, char *src, int dst_size)
+{
+ int x;
+ char tmp[3] = { 0, };
+
+ for (x = 0; x < dst_size; x++) {
+ tmp[0] = src[x * 2];
+ tmp[1] = src[x * 2 + 1];
+ dst[x] = (unsigned char)simple_strtol(tmp, NULL, 16);
+ }
+}
+
+static int ecryptfs_hash_digest(struct crypto_shash *tfm,
+ char *src, int len, char *dst)
+{
+ SHASH_DESC_ON_STACK(desc, tfm);
+ int err;
+
+ desc->tfm = tfm;
+ desc->flags = CRYPTO_TFM_REQ_MAY_SLEEP;
+ err = crypto_shash_digest(desc, src, len, dst);
+ shash_desc_zero(desc);
+ return err;
+}
+
+/**
+ * ecryptfs_calculate_md5 - calculates the md5 of @src
+ * @dst: Pointer to 16 bytes of allocated memory
+ * @crypt_stat: Pointer to crypt_stat struct for the current inode
+ * @src: Data to be md5'd
+ * @len: Length of @src
+ *
+ * Uses the allocated crypto context that crypt_stat references to
+ * generate the MD5 sum of the contents of src.
+ */
+static int ecryptfs_calculate_md5(char *dst,
+ struct ecryptfs_crypt_stat *crypt_stat,
+ char *src, int len)
+{
+ struct crypto_shash *tfm;
+ int rc = 0;
+
+ tfm = crypt_stat->hash_tfm;
+ rc = ecryptfs_hash_digest(tfm, src, len, dst);
+ if (rc) {
+ printk(KERN_ERR
+ "%s: Error computing crypto hash; rc = [%d]\n",
+ __func__, rc);
+ goto out;
+ }
+out:
+ return rc;
+}
+
+static int ecryptfs_crypto_api_algify_cipher_name(char **algified_name,
+ char *cipher_name,
+ char *chaining_modifier)
+{
+ int cipher_name_len = strlen(cipher_name);
+ int chaining_modifier_len = strlen(chaining_modifier);
+ int algified_name_len;
+ int rc;
+
+ algified_name_len = (chaining_modifier_len + cipher_name_len + 3);
+ (*algified_name) = kmalloc(algified_name_len, GFP_KERNEL);
+ if (!(*algified_name)) {
+ rc = -ENOMEM;
+ goto out;
+ }
+ snprintf((*algified_name), algified_name_len, "%s(%s)",
+ chaining_modifier, cipher_name);
+ rc = 0;
+out:
+ return rc;
+}
+
+/**
+ * ecryptfs_derive_iv
+ * @iv: destination for the derived iv vale
+ * @crypt_stat: Pointer to crypt_stat struct for the current inode
+ * @offset: Offset of the extent whose IV we are to derive
+ *
+ * Generate the initialization vector from the given root IV and page
+ * offset.
+ *
+ * Returns zero on success; non-zero on error.
+ */
+int ecryptfs_derive_iv(char *iv, struct ecryptfs_crypt_stat *crypt_stat,
+ loff_t offset)
+{
+ int rc = 0;
+ char dst[MD5_DIGEST_SIZE];
+ char src[ECRYPTFS_MAX_IV_BYTES + 16];
+
+ if (unlikely(ecryptfs_verbosity > 0)) {
+ ecryptfs_printk(KERN_DEBUG, "root iv:\n");
+ ecryptfs_dump_hex(crypt_stat->root_iv, crypt_stat->iv_bytes);
+ }
+ /* TODO: It is probably secure to just cast the least
+ * significant bits of the root IV into an unsigned long and
+ * add the offset to that rather than go through all this
+ * hashing business. -Halcrow */
+ memcpy(src, crypt_stat->root_iv, crypt_stat->iv_bytes);
+ memset((src + crypt_stat->iv_bytes), 0, 16);
+ snprintf((src + crypt_stat->iv_bytes), 16, "%lld", offset);
+ if (unlikely(ecryptfs_verbosity > 0)) {
+ ecryptfs_printk(KERN_DEBUG, "source:\n");
+ ecryptfs_dump_hex(src, (crypt_stat->iv_bytes + 16));
+ }
+ rc = ecryptfs_calculate_md5(dst, crypt_stat, src,
+ (crypt_stat->iv_bytes + 16));
+ if (rc) {
+ ecryptfs_printk(KERN_WARNING, "Error attempting to compute "
+ "MD5 while generating IV for a page\n");
+ goto out;
+ }
+ memcpy(iv, dst, crypt_stat->iv_bytes);
+ if (unlikely(ecryptfs_verbosity > 0)) {
+ ecryptfs_printk(KERN_DEBUG, "derived iv:\n");
+ ecryptfs_dump_hex(iv, crypt_stat->iv_bytes);
+ }
+out:
+ return rc;
+}
+
+/**
+ * ecryptfs_init_crypt_stat
+ * @crypt_stat: Pointer to the crypt_stat struct to initialize.
+ *
+ * Initialize the crypt_stat structure.
+ */
+int ecryptfs_init_crypt_stat(struct ecryptfs_crypt_stat *crypt_stat)
+{
+ struct crypto_shash *tfm;
+ int rc;
+
+ tfm = crypto_alloc_shash(ECRYPTFS_DEFAULT_HASH, 0, 0);
+ if (IS_ERR(tfm)) {
+ rc = PTR_ERR(tfm);
+ ecryptfs_printk(KERN_ERR, "Error attempting to "
+ "allocate crypto context; rc = [%d]\n",
+ rc);
+ return rc;
+ }
+
+ memset((void *)crypt_stat, 0, sizeof(struct ecryptfs_crypt_stat));
+ INIT_LIST_HEAD(&crypt_stat->keysig_list);
+ mutex_init(&crypt_stat->keysig_list_mutex);
+ mutex_init(&crypt_stat->cs_mutex);
+ mutex_init(&crypt_stat->cs_tfm_mutex);
+ crypt_stat->hash_tfm = tfm;
+ crypt_stat->flags |= ECRYPTFS_STRUCT_INITIALIZED;
+
+ return 0;
+}
+
+/**
+ * ecryptfs_destroy_crypt_stat
+ * @crypt_stat: Pointer to the crypt_stat struct to initialize.
+ *
+ * Releases all memory associated with a crypt_stat struct.
+ */
+void ecryptfs_destroy_crypt_stat(struct ecryptfs_crypt_stat *crypt_stat)
+{
+ struct ecryptfs_key_sig *key_sig, *key_sig_tmp;
+
+ crypto_free_skcipher(crypt_stat->tfm);
+ crypto_free_shash(crypt_stat->hash_tfm);
+ list_for_each_entry_safe(key_sig, key_sig_tmp,
+ &crypt_stat->keysig_list, crypt_stat_list) {
+ list_del(&key_sig->crypt_stat_list);
+ kmem_cache_free(ecryptfs_key_sig_cache, key_sig);
+ }
+ memset(crypt_stat, 0, sizeof(struct ecryptfs_crypt_stat));
+}
+
+void ecryptfs_destroy_mount_crypt_stat(
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat)
+{
+ struct ecryptfs_global_auth_tok *auth_tok, *auth_tok_tmp;
+
+ if (!(mount_crypt_stat->flags & ECRYPTFS_MOUNT_CRYPT_STAT_INITIALIZED))
+ return;
+ mutex_lock(&mount_crypt_stat->global_auth_tok_list_mutex);
+ list_for_each_entry_safe(auth_tok, auth_tok_tmp,
+ &mount_crypt_stat->global_auth_tok_list,
+ mount_crypt_stat_list) {
+ list_del(&auth_tok->mount_crypt_stat_list);
+ if (!(auth_tok->flags & ECRYPTFS_AUTH_TOK_INVALID))
+ key_put(auth_tok->global_auth_tok_key);
+ kmem_cache_free(ecryptfs_global_auth_tok_cache, auth_tok);
+ }
+ mutex_unlock(&mount_crypt_stat->global_auth_tok_list_mutex);
+ memset(mount_crypt_stat, 0, sizeof(struct ecryptfs_mount_crypt_stat));
+}
+
+/**
+ * virt_to_scatterlist
+ * @addr: Virtual address
+ * @size: Size of data; should be an even multiple of the block size
+ * @sg: Pointer to scatterlist array; set to NULL to obtain only
+ * the number of scatterlist structs required in array
+ * @sg_size: Max array size
+ *
+ * Fills in a scatterlist array with page references for a passed
+ * virtual address.
+ *
+ * Returns the number of scatterlist structs in array used
+ */
+int virt_to_scatterlist(const void *addr, int size, struct scatterlist *sg,
+ int sg_size)
+{
+ int i = 0;
+ struct page *pg;
+ int offset;
+ int remainder_of_page;
+
+ sg_init_table(sg, sg_size);
+
+ while (size > 0 && i < sg_size) {
+ pg = virt_to_page(addr);
+ offset = offset_in_page(addr);
+ sg_set_page(&sg[i], pg, 0, offset);
+ remainder_of_page = PAGE_SIZE - offset;
+ if (size >= remainder_of_page) {
+ sg[i].length = remainder_of_page;
+ addr += remainder_of_page;
+ size -= remainder_of_page;
+ } else {
+ sg[i].length = size;
+ addr += size;
+ size = 0;
+ }
+ i++;
+ }
+ if (size > 0)
+ return -ENOMEM;
+ return i;
+}
+
+struct extent_crypt_result {
+ struct completion completion;
+ int rc;
+};
+
+static void extent_crypt_complete(struct crypto_async_request *req, int rc)
+{
+ struct extent_crypt_result *ecr = req->data;
+
+ if (rc == -EINPROGRESS)
+ return;
+
+ ecr->rc = rc;
+ complete(&ecr->completion);
+}
+
+/**
+ * crypt_scatterlist
+ * @crypt_stat: Pointer to the crypt_stat struct to initialize.
+ * @dst_sg: Destination of the data after performing the crypto operation
+ * @src_sg: Data to be encrypted or decrypted
+ * @size: Length of data
+ * @iv: IV to use
+ * @op: ENCRYPT or DECRYPT to indicate the desired operation
+ *
+ * Returns the number of bytes encrypted or decrypted; negative value on error
+ */
+static int crypt_scatterlist(struct ecryptfs_crypt_stat *crypt_stat,
+ struct scatterlist *dst_sg,
+ struct scatterlist *src_sg, int size,
+ unsigned char *iv, int op)
+{
+ struct skcipher_request *req = NULL;
+ struct extent_crypt_result ecr;
+ int rc = 0;
+
+ BUG_ON(!crypt_stat || !crypt_stat->tfm
+ || !(crypt_stat->flags & ECRYPTFS_STRUCT_INITIALIZED));
+ if (unlikely(ecryptfs_verbosity > 0)) {
+ ecryptfs_printk(KERN_DEBUG, "Key size [%zd]; key:\n",
+ crypt_stat->key_size);
+ ecryptfs_dump_hex(crypt_stat->key,
+ crypt_stat->key_size);
+ }
+
+ init_completion(&ecr.completion);
+
+ mutex_lock(&crypt_stat->cs_tfm_mutex);
+ req = skcipher_request_alloc(crypt_stat->tfm, GFP_NOFS);
+ if (!req) {
+ mutex_unlock(&crypt_stat->cs_tfm_mutex);
+ rc = -ENOMEM;
+ goto out;
+ }
+
+ skcipher_request_set_callback(req,
+ CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP,
+ extent_crypt_complete, &ecr);
+ /* Consider doing this once, when the file is opened */
+ if (!(crypt_stat->flags & ECRYPTFS_KEY_SET)) {
+ rc = crypto_skcipher_setkey(crypt_stat->tfm, crypt_stat->key,
+ crypt_stat->key_size);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR,
+ "Error setting key; rc = [%d]\n",
+ rc);
+ mutex_unlock(&crypt_stat->cs_tfm_mutex);
+ rc = -EINVAL;
+ goto out;
+ }
+ crypt_stat->flags |= ECRYPTFS_KEY_SET;
+ }
+ mutex_unlock(&crypt_stat->cs_tfm_mutex);
+ skcipher_request_set_crypt(req, src_sg, dst_sg, size, iv);
+ rc = op == ENCRYPT ? crypto_skcipher_encrypt(req) :
+ crypto_skcipher_decrypt(req);
+ if (rc == -EINPROGRESS || rc == -EBUSY) {
+ struct extent_crypt_result *ecr = req->base.data;
+
+ wait_for_completion(&ecr->completion);
+ rc = ecr->rc;
+ reinit_completion(&ecr->completion);
+ }
+out:
+ skcipher_request_free(req);
+ return rc;
+}
+
+/**
+ * lower_offset_for_page
+ *
+ * Convert an eCryptfs page index into a lower byte offset
+ */
+static loff_t lower_offset_for_page(struct ecryptfs_crypt_stat *crypt_stat,
+ struct page *page)
+{
+ return ecryptfs_lower_header_size(crypt_stat) +
+ ((loff_t)page->index << PAGE_SHIFT);
+}
+
+/**
+ * crypt_extent
+ * @crypt_stat: crypt_stat containing cryptographic context for the
+ * encryption operation
+ * @dst_page: The page to write the result into
+ * @src_page: The page to read from
+ * @extent_offset: Page extent offset for use in generating IV
+ * @op: ENCRYPT or DECRYPT to indicate the desired operation
+ *
+ * Encrypts or decrypts one extent of data.
+ *
+ * Return zero on success; non-zero otherwise
+ */
+static int crypt_extent(struct ecryptfs_crypt_stat *crypt_stat,
+ struct page *dst_page,
+ struct page *src_page,
+ unsigned long extent_offset, int op)
+{
+ pgoff_t page_index = op == ENCRYPT ? src_page->index : dst_page->index;
+ loff_t extent_base;
+ char extent_iv[ECRYPTFS_MAX_IV_BYTES];
+ struct scatterlist src_sg, dst_sg;
+ size_t extent_size = crypt_stat->extent_size;
+ int rc;
+
+ extent_base = (((loff_t)page_index) * (PAGE_SIZE / extent_size));
+ rc = ecryptfs_derive_iv(extent_iv, crypt_stat,
+ (extent_base + extent_offset));
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error attempting to derive IV for "
+ "extent [0x%.16llx]; rc = [%d]\n",
+ (unsigned long long)(extent_base + extent_offset), rc);
+ goto out;
+ }
+
+ sg_init_table(&src_sg, 1);
+ sg_init_table(&dst_sg, 1);
+
+ sg_set_page(&src_sg, src_page, extent_size,
+ extent_offset * extent_size);
+ sg_set_page(&dst_sg, dst_page, extent_size,
+ extent_offset * extent_size);
+
+ rc = crypt_scatterlist(crypt_stat, &dst_sg, &src_sg, extent_size,
+ extent_iv, op);
+ if (rc < 0) {
+ printk(KERN_ERR "%s: Error attempting to crypt page with "
+ "page_index = [%ld], extent_offset = [%ld]; "
+ "rc = [%d]\n", __func__, page_index, extent_offset, rc);
+ goto out;
+ }
+ rc = 0;
+out:
+ return rc;
+}
+
+/**
+ * ecryptfs_encrypt_page
+ * @page: Page mapped from the eCryptfs inode for the file; contains
+ * decrypted content that needs to be encrypted (to a temporary
+ * page; not in place) and written out to the lower file
+ *
+ * Encrypt an eCryptfs page. This is done on a per-extent basis. Note
+ * that eCryptfs pages may straddle the lower pages -- for instance,
+ * if the file was created on a machine with an 8K page size
+ * (resulting in an 8K header), and then the file is copied onto a
+ * host with a 32K page size, then when reading page 0 of the eCryptfs
+ * file, 24K of page 0 of the lower file will be read and decrypted,
+ * and then 8K of page 1 of the lower file will be read and decrypted.
+ *
+ * Returns zero on success; negative on error
+ */
+int ecryptfs_encrypt_page(struct page *page)
+{
+ struct inode *ecryptfs_inode;
+ struct ecryptfs_crypt_stat *crypt_stat;
+ char *enc_extent_virt;
+ struct page *enc_extent_page = NULL;
+ loff_t extent_offset;
+ loff_t lower_offset;
+ int rc = 0;
+
+ ecryptfs_inode = page->mapping->host;
+ crypt_stat =
+ &(ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat);
+ BUG_ON(!(crypt_stat->flags & ECRYPTFS_ENCRYPTED));
+ enc_extent_page = alloc_page(GFP_USER);
+ if (!enc_extent_page) {
+ rc = -ENOMEM;
+ ecryptfs_printk(KERN_ERR, "Error allocating memory for "
+ "encrypted extent\n");
+ goto out;
+ }
+
+ for (extent_offset = 0;
+ extent_offset < (PAGE_SIZE / crypt_stat->extent_size);
+ extent_offset++) {
+ rc = crypt_extent(crypt_stat, enc_extent_page, page,
+ extent_offset, ENCRYPT);
+ if (rc) {
+ printk(KERN_ERR "%s: Error encrypting extent; "
+ "rc = [%d]\n", __func__, rc);
+ goto out;
+ }
+ }
+
+ lower_offset = lower_offset_for_page(crypt_stat, page);
+ enc_extent_virt = kmap(enc_extent_page);
+ rc = ecryptfs_write_lower(ecryptfs_inode, enc_extent_virt, lower_offset,
+ PAGE_SIZE);
+ kunmap(enc_extent_page);
+ if (rc < 0) {
+ ecryptfs_printk(KERN_ERR,
+ "Error attempting to write lower page; rc = [%d]\n",
+ rc);
+ goto out;
+ }
+ rc = 0;
+out:
+ if (enc_extent_page) {
+ __free_page(enc_extent_page);
+ }
+ return rc;
+}
+
+/**
+ * ecryptfs_decrypt_page
+ * @page: Page mapped from the eCryptfs inode for the file; data read
+ * and decrypted from the lower file will be written into this
+ * page
+ *
+ * Decrypt an eCryptfs page. This is done on a per-extent basis. Note
+ * that eCryptfs pages may straddle the lower pages -- for instance,
+ * if the file was created on a machine with an 8K page size
+ * (resulting in an 8K header), and then the file is copied onto a
+ * host with a 32K page size, then when reading page 0 of the eCryptfs
+ * file, 24K of page 0 of the lower file will be read and decrypted,
+ * and then 8K of page 1 of the lower file will be read and decrypted.
+ *
+ * Returns zero on success; negative on error
+ */
+int ecryptfs_decrypt_page(struct page *page)
+{
+ struct inode *ecryptfs_inode;
+ struct ecryptfs_crypt_stat *crypt_stat;
+ char *page_virt;
+ unsigned long extent_offset;
+ loff_t lower_offset;
+ int rc = 0;
+
+ ecryptfs_inode = page->mapping->host;
+ crypt_stat =
+ &(ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat);
+ BUG_ON(!(crypt_stat->flags & ECRYPTFS_ENCRYPTED));
+
+ lower_offset = lower_offset_for_page(crypt_stat, page);
+ page_virt = kmap(page);
+ rc = ecryptfs_read_lower(page_virt, lower_offset, PAGE_SIZE,
+ ecryptfs_inode);
+ kunmap(page);
+ if (rc < 0) {
+ ecryptfs_printk(KERN_ERR,
+ "Error attempting to read lower page; rc = [%d]\n",
+ rc);
+ goto out;
+ }
+
+ for (extent_offset = 0;
+ extent_offset < (PAGE_SIZE / crypt_stat->extent_size);
+ extent_offset++) {
+ rc = crypt_extent(crypt_stat, page, page,
+ extent_offset, DECRYPT);
+ if (rc) {
+ printk(KERN_ERR "%s: Error encrypting extent; "
+ "rc = [%d]\n", __func__, rc);
+ goto out;
+ }
+ }
+out:
+ return rc;
+}
+
+#define ECRYPTFS_MAX_SCATTERLIST_LEN 4
+
+/**
+ * ecryptfs_init_crypt_ctx
+ * @crypt_stat: Uninitialized crypt stats structure
+ *
+ * Initialize the crypto context.
+ *
+ * TODO: Performance: Keep a cache of initialized cipher contexts;
+ * only init if needed
+ */
+int ecryptfs_init_crypt_ctx(struct ecryptfs_crypt_stat *crypt_stat)
+{
+ char *full_alg_name;
+ int rc = -EINVAL;
+
+ ecryptfs_printk(KERN_DEBUG,
+ "Initializing cipher [%s]; strlen = [%d]; "
+ "key_size_bits = [%zd]\n",
+ crypt_stat->cipher, (int)strlen(crypt_stat->cipher),
+ crypt_stat->key_size << 3);
+ mutex_lock(&crypt_stat->cs_tfm_mutex);
+ if (crypt_stat->tfm) {
+ rc = 0;
+ goto out_unlock;
+ }
+ rc = ecryptfs_crypto_api_algify_cipher_name(&full_alg_name,
+ crypt_stat->cipher, "cbc");
+ if (rc)
+ goto out_unlock;
+ crypt_stat->tfm = crypto_alloc_skcipher(full_alg_name, 0, 0);
+ if (IS_ERR(crypt_stat->tfm)) {
+ rc = PTR_ERR(crypt_stat->tfm);
+ crypt_stat->tfm = NULL;
+ ecryptfs_printk(KERN_ERR, "cryptfs: init_crypt_ctx(): "
+ "Error initializing cipher [%s]\n",
+ full_alg_name);
+ goto out_free;
+ }
+ crypto_skcipher_set_flags(crypt_stat->tfm, CRYPTO_TFM_REQ_WEAK_KEY);
+ rc = 0;
+out_free:
+ kfree(full_alg_name);
+out_unlock:
+ mutex_unlock(&crypt_stat->cs_tfm_mutex);
+ return rc;
+}
+
+static void set_extent_mask_and_shift(struct ecryptfs_crypt_stat *crypt_stat)
+{
+ int extent_size_tmp;
+
+ crypt_stat->extent_mask = 0xFFFFFFFF;
+ crypt_stat->extent_shift = 0;
+ if (crypt_stat->extent_size == 0)
+ return;
+ extent_size_tmp = crypt_stat->extent_size;
+ while ((extent_size_tmp & 0x01) == 0) {
+ extent_size_tmp >>= 1;
+ crypt_stat->extent_mask <<= 1;
+ crypt_stat->extent_shift++;
+ }
+}
+
+void ecryptfs_set_default_sizes(struct ecryptfs_crypt_stat *crypt_stat)
+{
+ /* Default values; may be overwritten as we are parsing the
+ * packets. */
+ crypt_stat->extent_size = ECRYPTFS_DEFAULT_EXTENT_SIZE;
+ set_extent_mask_and_shift(crypt_stat);
+ crypt_stat->iv_bytes = ECRYPTFS_DEFAULT_IV_BYTES;
+ if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR)
+ crypt_stat->metadata_size = ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE;
+ else {
+ if (PAGE_SIZE <= ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE)
+ crypt_stat->metadata_size =
+ ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE;
+ else
+ crypt_stat->metadata_size = PAGE_SIZE;
+ }
+}
+
+/**
+ * ecryptfs_compute_root_iv
+ * @crypt_stats
+ *
+ * On error, sets the root IV to all 0's.
+ */
+int ecryptfs_compute_root_iv(struct ecryptfs_crypt_stat *crypt_stat)
+{
+ int rc = 0;
+ char dst[MD5_DIGEST_SIZE];
+
+ BUG_ON(crypt_stat->iv_bytes > MD5_DIGEST_SIZE);
+ BUG_ON(crypt_stat->iv_bytes <= 0);
+ if (!(crypt_stat->flags & ECRYPTFS_KEY_VALID)) {
+ rc = -EINVAL;
+ ecryptfs_printk(KERN_WARNING, "Session key not valid; "
+ "cannot generate root IV\n");
+ goto out;
+ }
+ rc = ecryptfs_calculate_md5(dst, crypt_stat, crypt_stat->key,
+ crypt_stat->key_size);
+ if (rc) {
+ ecryptfs_printk(KERN_WARNING, "Error attempting to compute "
+ "MD5 while generating root IV\n");
+ goto out;
+ }
+ memcpy(crypt_stat->root_iv, dst, crypt_stat->iv_bytes);
+out:
+ if (rc) {
+ memset(crypt_stat->root_iv, 0, crypt_stat->iv_bytes);
+ crypt_stat->flags |= ECRYPTFS_SECURITY_WARNING;
+ }
+ return rc;
+}
+
+static void ecryptfs_generate_new_key(struct ecryptfs_crypt_stat *crypt_stat)
+{
+ get_random_bytes(crypt_stat->key, crypt_stat->key_size);
+ crypt_stat->flags |= ECRYPTFS_KEY_VALID;
+ ecryptfs_compute_root_iv(crypt_stat);
+ if (unlikely(ecryptfs_verbosity > 0)) {
+ ecryptfs_printk(KERN_DEBUG, "Generated new session key:\n");
+ ecryptfs_dump_hex(crypt_stat->key,
+ crypt_stat->key_size);
+ }
+}
+
+/**
+ * ecryptfs_copy_mount_wide_flags_to_inode_flags
+ * @crypt_stat: The inode's cryptographic context
+ * @mount_crypt_stat: The mount point's cryptographic context
+ *
+ * This function propagates the mount-wide flags to individual inode
+ * flags.
+ */
+static void ecryptfs_copy_mount_wide_flags_to_inode_flags(
+ struct ecryptfs_crypt_stat *crypt_stat,
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat)
+{
+ if (mount_crypt_stat->flags & ECRYPTFS_XATTR_METADATA_ENABLED)
+ crypt_stat->flags |= ECRYPTFS_METADATA_IN_XATTR;
+ if (mount_crypt_stat->flags & ECRYPTFS_ENCRYPTED_VIEW_ENABLED)
+ crypt_stat->flags |= ECRYPTFS_VIEW_AS_ENCRYPTED;
+ if (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES) {
+ crypt_stat->flags |= ECRYPTFS_ENCRYPT_FILENAMES;
+ if (mount_crypt_stat->flags
+ & ECRYPTFS_GLOBAL_ENCFN_USE_MOUNT_FNEK)
+ crypt_stat->flags |= ECRYPTFS_ENCFN_USE_MOUNT_FNEK;
+ else if (mount_crypt_stat->flags
+ & ECRYPTFS_GLOBAL_ENCFN_USE_FEK)
+ crypt_stat->flags |= ECRYPTFS_ENCFN_USE_FEK;
+ }
+}
+
+static int ecryptfs_copy_mount_wide_sigs_to_inode_sigs(
+ struct ecryptfs_crypt_stat *crypt_stat,
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat)
+{
+ struct ecryptfs_global_auth_tok *global_auth_tok;
+ int rc = 0;
+
+ mutex_lock(&crypt_stat->keysig_list_mutex);
+ mutex_lock(&mount_crypt_stat->global_auth_tok_list_mutex);
+
+ list_for_each_entry(global_auth_tok,
+ &mount_crypt_stat->global_auth_tok_list,
+ mount_crypt_stat_list) {
+ if (global_auth_tok->flags & ECRYPTFS_AUTH_TOK_FNEK)
+ continue;
+ rc = ecryptfs_add_keysig(crypt_stat, global_auth_tok->sig);
+ if (rc) {
+ printk(KERN_ERR "Error adding keysig; rc = [%d]\n", rc);
+ goto out;
+ }
+ }
+
+out:
+ mutex_unlock(&mount_crypt_stat->global_auth_tok_list_mutex);
+ mutex_unlock(&crypt_stat->keysig_list_mutex);
+ return rc;
+}
+
+/**
+ * ecryptfs_set_default_crypt_stat_vals
+ * @crypt_stat: The inode's cryptographic context
+ * @mount_crypt_stat: The mount point's cryptographic context
+ *
+ * Default values in the event that policy does not override them.
+ */
+static void ecryptfs_set_default_crypt_stat_vals(
+ struct ecryptfs_crypt_stat *crypt_stat,
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat)
+{
+ ecryptfs_copy_mount_wide_flags_to_inode_flags(crypt_stat,
+ mount_crypt_stat);
+ ecryptfs_set_default_sizes(crypt_stat);
+ strcpy(crypt_stat->cipher, ECRYPTFS_DEFAULT_CIPHER);
+ crypt_stat->key_size = ECRYPTFS_DEFAULT_KEY_BYTES;
+ crypt_stat->flags &= ~(ECRYPTFS_KEY_VALID);
+ crypt_stat->file_version = ECRYPTFS_FILE_VERSION;
+ crypt_stat->mount_crypt_stat = mount_crypt_stat;
+}
+
+/**
+ * ecryptfs_new_file_context
+ * @ecryptfs_inode: The eCryptfs inode
+ *
+ * If the crypto context for the file has not yet been established,
+ * this is where we do that. Establishing a new crypto context
+ * involves the following decisions:
+ * - What cipher to use?
+ * - What set of authentication tokens to use?
+ * Here we just worry about getting enough information into the
+ * authentication tokens so that we know that they are available.
+ * We associate the available authentication tokens with the new file
+ * via the set of signatures in the crypt_stat struct. Later, when
+ * the headers are actually written out, we may again defer to
+ * userspace to perform the encryption of the session key; for the
+ * foreseeable future, this will be the case with public key packets.
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+int ecryptfs_new_file_context(struct inode *ecryptfs_inode)
+{
+ struct ecryptfs_crypt_stat *crypt_stat =
+ &ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat;
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat =
+ &ecryptfs_superblock_to_private(
+ ecryptfs_inode->i_sb)->mount_crypt_stat;
+ int cipher_name_len;
+ int rc = 0;
+
+ ecryptfs_set_default_crypt_stat_vals(crypt_stat, mount_crypt_stat);
+ crypt_stat->flags |= (ECRYPTFS_ENCRYPTED | ECRYPTFS_KEY_VALID);
+ ecryptfs_copy_mount_wide_flags_to_inode_flags(crypt_stat,
+ mount_crypt_stat);
+ rc = ecryptfs_copy_mount_wide_sigs_to_inode_sigs(crypt_stat,
+ mount_crypt_stat);
+ if (rc) {
+ printk(KERN_ERR "Error attempting to copy mount-wide key sigs "
+ "to the inode key sigs; rc = [%d]\n", rc);
+ goto out;
+ }
+ cipher_name_len =
+ strlen(mount_crypt_stat->global_default_cipher_name);
+ memcpy(crypt_stat->cipher,
+ mount_crypt_stat->global_default_cipher_name,
+ cipher_name_len);
+ crypt_stat->cipher[cipher_name_len] = '\0';
+ crypt_stat->key_size =
+ mount_crypt_stat->global_default_cipher_key_size;
+ ecryptfs_generate_new_key(crypt_stat);
+ rc = ecryptfs_init_crypt_ctx(crypt_stat);
+ if (rc)
+ ecryptfs_printk(KERN_ERR, "Error initializing cryptographic "
+ "context for cipher [%s]: rc = [%d]\n",
+ crypt_stat->cipher, rc);
+out:
+ return rc;
+}
+
+/**
+ * ecryptfs_validate_marker - check for the ecryptfs marker
+ * @data: The data block in which to check
+ *
+ * Returns zero if marker found; -EINVAL if not found
+ */
+static int ecryptfs_validate_marker(char *data)
+{
+ u32 m_1, m_2;
+
+ m_1 = get_unaligned_be32(data);
+ m_2 = get_unaligned_be32(data + 4);
+ if ((m_1 ^ MAGIC_ECRYPTFS_MARKER) == m_2)
+ return 0;
+ ecryptfs_printk(KERN_DEBUG, "m_1 = [0x%.8x]; m_2 = [0x%.8x]; "
+ "MAGIC_ECRYPTFS_MARKER = [0x%.8x]\n", m_1, m_2,
+ MAGIC_ECRYPTFS_MARKER);
+ ecryptfs_printk(KERN_DEBUG, "(m_1 ^ MAGIC_ECRYPTFS_MARKER) = "
+ "[0x%.8x]\n", (m_1 ^ MAGIC_ECRYPTFS_MARKER));
+ return -EINVAL;
+}
+
+struct ecryptfs_flag_map_elem {
+ u32 file_flag;
+ u32 local_flag;
+};
+
+/* Add support for additional flags by adding elements here. */
+static struct ecryptfs_flag_map_elem ecryptfs_flag_map[] = {
+ {0x00000001, ECRYPTFS_ENABLE_HMAC},
+ {0x00000002, ECRYPTFS_ENCRYPTED},
+ {0x00000004, ECRYPTFS_METADATA_IN_XATTR},
+ {0x00000008, ECRYPTFS_ENCRYPT_FILENAMES}
+};
+
+/**
+ * ecryptfs_process_flags
+ * @crypt_stat: The cryptographic context
+ * @page_virt: Source data to be parsed
+ * @bytes_read: Updated with the number of bytes read
+ *
+ * Returns zero on success; non-zero if the flag set is invalid
+ */
+static int ecryptfs_process_flags(struct ecryptfs_crypt_stat *crypt_stat,
+ char *page_virt, int *bytes_read)
+{
+ int rc = 0;
+ int i;
+ u32 flags;
+
+ flags = get_unaligned_be32(page_virt);
+ for (i = 0; i < ARRAY_SIZE(ecryptfs_flag_map); i++)
+ if (flags & ecryptfs_flag_map[i].file_flag) {
+ crypt_stat->flags |= ecryptfs_flag_map[i].local_flag;
+ } else
+ crypt_stat->flags &= ~(ecryptfs_flag_map[i].local_flag);
+ /* Version is in top 8 bits of the 32-bit flag vector */
+ crypt_stat->file_version = ((flags >> 24) & 0xFF);
+ (*bytes_read) = 4;
+ return rc;
+}
+
+/**
+ * write_ecryptfs_marker
+ * @page_virt: The pointer to in a page to begin writing the marker
+ * @written: Number of bytes written
+ *
+ * Marker = 0x3c81b7f5
+ */
+static void write_ecryptfs_marker(char *page_virt, size_t *written)
+{
+ u32 m_1, m_2;
+
+ get_random_bytes(&m_1, (MAGIC_ECRYPTFS_MARKER_SIZE_BYTES / 2));
+ m_2 = (m_1 ^ MAGIC_ECRYPTFS_MARKER);
+ put_unaligned_be32(m_1, page_virt);
+ page_virt += (MAGIC_ECRYPTFS_MARKER_SIZE_BYTES / 2);
+ put_unaligned_be32(m_2, page_virt);
+ (*written) = MAGIC_ECRYPTFS_MARKER_SIZE_BYTES;
+}
+
+void ecryptfs_write_crypt_stat_flags(char *page_virt,
+ struct ecryptfs_crypt_stat *crypt_stat,
+ size_t *written)
+{
+ u32 flags = 0;
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(ecryptfs_flag_map); i++)
+ if (crypt_stat->flags & ecryptfs_flag_map[i].local_flag)
+ flags |= ecryptfs_flag_map[i].file_flag;
+ /* Version is in top 8 bits of the 32-bit flag vector */
+ flags |= ((((u8)crypt_stat->file_version) << 24) & 0xFF000000);
+ put_unaligned_be32(flags, page_virt);
+ (*written) = 4;
+}
+
+struct ecryptfs_cipher_code_str_map_elem {
+ char cipher_str[16];
+ u8 cipher_code;
+};
+
+/* Add support for additional ciphers by adding elements here. The
+ * cipher_code is whatever OpenPGP applications use to identify the
+ * ciphers. List in order of probability. */
+static struct ecryptfs_cipher_code_str_map_elem
+ecryptfs_cipher_code_str_map[] = {
+ {"aes",RFC2440_CIPHER_AES_128 },
+ {"blowfish", RFC2440_CIPHER_BLOWFISH},
+ {"des3_ede", RFC2440_CIPHER_DES3_EDE},
+ {"cast5", RFC2440_CIPHER_CAST_5},
+ {"twofish", RFC2440_CIPHER_TWOFISH},
+ {"cast6", RFC2440_CIPHER_CAST_6},
+ {"aes", RFC2440_CIPHER_AES_192},
+ {"aes", RFC2440_CIPHER_AES_256}
+};
+
+/**
+ * ecryptfs_code_for_cipher_string
+ * @cipher_name: The string alias for the cipher
+ * @key_bytes: Length of key in bytes; used for AES code selection
+ *
+ * Returns zero on no match, or the cipher code on match
+ */
+u8 ecryptfs_code_for_cipher_string(char *cipher_name, size_t key_bytes)
+{
+ int i;
+ u8 code = 0;
+ struct ecryptfs_cipher_code_str_map_elem *map =
+ ecryptfs_cipher_code_str_map;
+
+ if (strcmp(cipher_name, "aes") == 0) {
+ switch (key_bytes) {
+ case 16:
+ code = RFC2440_CIPHER_AES_128;
+ break;
+ case 24:
+ code = RFC2440_CIPHER_AES_192;
+ break;
+ case 32:
+ code = RFC2440_CIPHER_AES_256;
+ }
+ } else {
+ for (i = 0; i < ARRAY_SIZE(ecryptfs_cipher_code_str_map); i++)
+ if (strcmp(cipher_name, map[i].cipher_str) == 0) {
+ code = map[i].cipher_code;
+ break;
+ }
+ }
+ return code;
+}
+
+/**
+ * ecryptfs_cipher_code_to_string
+ * @str: Destination to write out the cipher name
+ * @cipher_code: The code to convert to cipher name string
+ *
+ * Returns zero on success
+ */
+int ecryptfs_cipher_code_to_string(char *str, u8 cipher_code)
+{
+ int rc = 0;
+ int i;
+
+ str[0] = '\0';
+ for (i = 0; i < ARRAY_SIZE(ecryptfs_cipher_code_str_map); i++)
+ if (cipher_code == ecryptfs_cipher_code_str_map[i].cipher_code)
+ strcpy(str, ecryptfs_cipher_code_str_map[i].cipher_str);
+ if (str[0] == '\0') {
+ ecryptfs_printk(KERN_WARNING, "Cipher code not recognized: "
+ "[%d]\n", cipher_code);
+ rc = -EINVAL;
+ }
+ return rc;
+}
+
+int ecryptfs_read_and_validate_header_region(struct inode *inode)
+{
+ u8 file_size[ECRYPTFS_SIZE_AND_MARKER_BYTES];
+ u8 *marker = file_size + ECRYPTFS_FILE_SIZE_BYTES;
+ int rc;
+
+ rc = ecryptfs_read_lower(file_size, 0, ECRYPTFS_SIZE_AND_MARKER_BYTES,
+ inode);
+ if (rc < ECRYPTFS_SIZE_AND_MARKER_BYTES)
+ return rc >= 0 ? -EINVAL : rc;
+ rc = ecryptfs_validate_marker(marker);
+ if (!rc)
+ ecryptfs_i_size_init(file_size, inode);
+ return rc;
+}
+
+void
+ecryptfs_write_header_metadata(char *virt,
+ struct ecryptfs_crypt_stat *crypt_stat,
+ size_t *written)
+{
+ u32 header_extent_size;
+ u16 num_header_extents_at_front;
+
+ header_extent_size = (u32)crypt_stat->extent_size;
+ num_header_extents_at_front =
+ (u16)(crypt_stat->metadata_size / crypt_stat->extent_size);
+ put_unaligned_be32(header_extent_size, virt);
+ virt += 4;
+ put_unaligned_be16(num_header_extents_at_front, virt);
+ (*written) = 6;
+}
+
+struct kmem_cache *ecryptfs_header_cache;
+
+/**
+ * ecryptfs_write_headers_virt
+ * @page_virt: The virtual address to write the headers to
+ * @max: The size of memory allocated at page_virt
+ * @size: Set to the number of bytes written by this function
+ * @crypt_stat: The cryptographic context
+ * @ecryptfs_dentry: The eCryptfs dentry
+ *
+ * Format version: 1
+ *
+ * Header Extent:
+ * Octets 0-7: Unencrypted file size (big-endian)
+ * Octets 8-15: eCryptfs special marker
+ * Octets 16-19: Flags
+ * Octet 16: File format version number (between 0 and 255)
+ * Octets 17-18: Reserved
+ * Octet 19: Bit 1 (lsb): Reserved
+ * Bit 2: Encrypted?
+ * Bits 3-8: Reserved
+ * Octets 20-23: Header extent size (big-endian)
+ * Octets 24-25: Number of header extents at front of file
+ * (big-endian)
+ * Octet 26: Begin RFC 2440 authentication token packet set
+ * Data Extent 0:
+ * Lower data (CBC encrypted)
+ * Data Extent 1:
+ * Lower data (CBC encrypted)
+ * ...
+ *
+ * Returns zero on success
+ */
+static int ecryptfs_write_headers_virt(char *page_virt, size_t max,
+ size_t *size,
+ struct ecryptfs_crypt_stat *crypt_stat,
+ struct dentry *ecryptfs_dentry)
+{
+ int rc;
+ size_t written;
+ size_t offset;
+
+ offset = ECRYPTFS_FILE_SIZE_BYTES;
+ write_ecryptfs_marker((page_virt + offset), &written);
+ offset += written;
+ ecryptfs_write_crypt_stat_flags((page_virt + offset), crypt_stat,
+ &written);
+ offset += written;
+ ecryptfs_write_header_metadata((page_virt + offset), crypt_stat,
+ &written);
+ offset += written;
+ rc = ecryptfs_generate_key_packet_set((page_virt + offset), crypt_stat,
+ ecryptfs_dentry, &written,
+ max - offset);
+ if (rc)
+ ecryptfs_printk(KERN_WARNING, "Error generating key packet "
+ "set; rc = [%d]\n", rc);
+ if (size) {
+ offset += written;
+ *size = offset;
+ }
+ return rc;
+}
+
+static int
+ecryptfs_write_metadata_to_contents(struct inode *ecryptfs_inode,
+ char *virt, size_t virt_len)
+{
+ int rc;
+
+ rc = ecryptfs_write_lower(ecryptfs_inode, virt,
+ 0, virt_len);
+ if (rc < 0)
+ printk(KERN_ERR "%s: Error attempting to write header "
+ "information to lower file; rc = [%d]\n", __func__, rc);
+ else
+ rc = 0;
+ return rc;
+}
+
+static int
+ecryptfs_write_metadata_to_xattr(struct dentry *ecryptfs_dentry,
+ struct inode *ecryptfs_inode,
+ char *page_virt, size_t size)
+{
+ int rc;
+
+ rc = ecryptfs_setxattr(ecryptfs_dentry, ecryptfs_inode,
+ ECRYPTFS_XATTR_NAME, page_virt, size, 0);
+ return rc;
+}
+
+static unsigned long ecryptfs_get_zeroed_pages(gfp_t gfp_mask,
+ unsigned int order)
+{
+ struct page *page;
+
+ page = alloc_pages(gfp_mask | __GFP_ZERO, order);
+ if (page)
+ return (unsigned long) page_address(page);
+ return 0;
+}
+
+/**
+ * ecryptfs_write_metadata
+ * @ecryptfs_dentry: The eCryptfs dentry, which should be negative
+ * @ecryptfs_inode: The newly created eCryptfs inode
+ *
+ * Write the file headers out. This will likely involve a userspace
+ * callout, in which the session key is encrypted with one or more
+ * public keys and/or the passphrase necessary to do the encryption is
+ * retrieved via a prompt. Exactly what happens at this point should
+ * be policy-dependent.
+ *
+ * Returns zero on success; non-zero on error
+ */
+int ecryptfs_write_metadata(struct dentry *ecryptfs_dentry,
+ struct inode *ecryptfs_inode)
+{
+ struct ecryptfs_crypt_stat *crypt_stat =
+ &ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat;
+ unsigned int order;
+ char *virt;
+ size_t virt_len;
+ size_t size = 0;
+ int rc = 0;
+
+ if (likely(crypt_stat->flags & ECRYPTFS_ENCRYPTED)) {
+ if (!(crypt_stat->flags & ECRYPTFS_KEY_VALID)) {
+ printk(KERN_ERR "Key is invalid; bailing out\n");
+ rc = -EINVAL;
+ goto out;
+ }
+ } else {
+ printk(KERN_WARNING "%s: Encrypted flag not set\n",
+ __func__);
+ rc = -EINVAL;
+ goto out;
+ }
+ virt_len = crypt_stat->metadata_size;
+ order = get_order(virt_len);
+ /* Released in this function */
+ virt = (char *)ecryptfs_get_zeroed_pages(GFP_KERNEL, order);
+ if (!virt) {
+ printk(KERN_ERR "%s: Out of memory\n", __func__);
+ rc = -ENOMEM;
+ goto out;
+ }
+ /* Zeroed page ensures the in-header unencrypted i_size is set to 0 */
+ rc = ecryptfs_write_headers_virt(virt, virt_len, &size, crypt_stat,
+ ecryptfs_dentry);
+ if (unlikely(rc)) {
+ printk(KERN_ERR "%s: Error whilst writing headers; rc = [%d]\n",
+ __func__, rc);
+ goto out_free;
+ }
+ if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR)
+ rc = ecryptfs_write_metadata_to_xattr(ecryptfs_dentry, ecryptfs_inode,
+ virt, size);
+ else
+ rc = ecryptfs_write_metadata_to_contents(ecryptfs_inode, virt,
+ virt_len);
+ if (rc) {
+ printk(KERN_ERR "%s: Error writing metadata out to lower file; "
+ "rc = [%d]\n", __func__, rc);
+ goto out_free;
+ }
+out_free:
+ free_pages((unsigned long)virt, order);
+out:
+ return rc;
+}
+
+#define ECRYPTFS_DONT_VALIDATE_HEADER_SIZE 0
+#define ECRYPTFS_VALIDATE_HEADER_SIZE 1
+static int parse_header_metadata(struct ecryptfs_crypt_stat *crypt_stat,
+ char *virt, int *bytes_read,
+ int validate_header_size)
+{
+ int rc = 0;
+ u32 header_extent_size;
+ u16 num_header_extents_at_front;
+
+ header_extent_size = get_unaligned_be32(virt);
+ virt += sizeof(__be32);
+ num_header_extents_at_front = get_unaligned_be16(virt);
+ crypt_stat->metadata_size = (((size_t)num_header_extents_at_front
+ * (size_t)header_extent_size));
+ (*bytes_read) = (sizeof(__be32) + sizeof(__be16));
+ if ((validate_header_size == ECRYPTFS_VALIDATE_HEADER_SIZE)
+ && (crypt_stat->metadata_size
+ < ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE)) {
+ rc = -EINVAL;
+ printk(KERN_WARNING "Invalid header size: [%zd]\n",
+ crypt_stat->metadata_size);
+ }
+ return rc;
+}
+
+/**
+ * set_default_header_data
+ * @crypt_stat: The cryptographic context
+ *
+ * For version 0 file format; this function is only for backwards
+ * compatibility for files created with the prior versions of
+ * eCryptfs.
+ */
+static void set_default_header_data(struct ecryptfs_crypt_stat *crypt_stat)
+{
+ crypt_stat->metadata_size = ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE;
+}
+
+void ecryptfs_i_size_init(const char *page_virt, struct inode *inode)
+{
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
+ struct ecryptfs_crypt_stat *crypt_stat;
+ u64 file_size;
+
+ crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat;
+ mount_crypt_stat =
+ &ecryptfs_superblock_to_private(inode->i_sb)->mount_crypt_stat;
+ if (mount_crypt_stat->flags & ECRYPTFS_ENCRYPTED_VIEW_ENABLED) {
+ file_size = i_size_read(ecryptfs_inode_to_lower(inode));
+ if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR)
+ file_size += crypt_stat->metadata_size;
+ } else
+ file_size = get_unaligned_be64(page_virt);
+ i_size_write(inode, (loff_t)file_size);
+ crypt_stat->flags |= ECRYPTFS_I_SIZE_INITIALIZED;
+}
+
+/**
+ * ecryptfs_read_headers_virt
+ * @page_virt: The virtual address into which to read the headers
+ * @crypt_stat: The cryptographic context
+ * @ecryptfs_dentry: The eCryptfs dentry
+ * @validate_header_size: Whether to validate the header size while reading
+ *
+ * Read/parse the header data. The header format is detailed in the
+ * comment block for the ecryptfs_write_headers_virt() function.
+ *
+ * Returns zero on success
+ */
+static int ecryptfs_read_headers_virt(char *page_virt,
+ struct ecryptfs_crypt_stat *crypt_stat,
+ struct dentry *ecryptfs_dentry,
+ int validate_header_size)
+{
+ int rc = 0;
+ int offset;
+ int bytes_read;
+
+ ecryptfs_set_default_sizes(crypt_stat);
+ crypt_stat->mount_crypt_stat = &ecryptfs_superblock_to_private(
+ ecryptfs_dentry->d_sb)->mount_crypt_stat;
+ offset = ECRYPTFS_FILE_SIZE_BYTES;
+ rc = ecryptfs_validate_marker(page_virt + offset);
+ if (rc)
+ goto out;
+ if (!(crypt_stat->flags & ECRYPTFS_I_SIZE_INITIALIZED))
+ ecryptfs_i_size_init(page_virt, d_inode(ecryptfs_dentry));
+ offset += MAGIC_ECRYPTFS_MARKER_SIZE_BYTES;
+ rc = ecryptfs_process_flags(crypt_stat, (page_virt + offset),
+ &bytes_read);
+ if (rc) {
+ ecryptfs_printk(KERN_WARNING, "Error processing flags\n");
+ goto out;
+ }
+ if (crypt_stat->file_version > ECRYPTFS_SUPPORTED_FILE_VERSION) {
+ ecryptfs_printk(KERN_WARNING, "File version is [%d]; only "
+ "file version [%d] is supported by this "
+ "version of eCryptfs\n",
+ crypt_stat->file_version,
+ ECRYPTFS_SUPPORTED_FILE_VERSION);
+ rc = -EINVAL;
+ goto out;
+ }
+ offset += bytes_read;
+ if (crypt_stat->file_version >= 1) {
+ rc = parse_header_metadata(crypt_stat, (page_virt + offset),
+ &bytes_read, validate_header_size);
+ if (rc) {
+ ecryptfs_printk(KERN_WARNING, "Error reading header "
+ "metadata; rc = [%d]\n", rc);
+ }
+ offset += bytes_read;
+ } else
+ set_default_header_data(crypt_stat);
+ rc = ecryptfs_parse_packet_set(crypt_stat, (page_virt + offset),
+ ecryptfs_dentry);
+out:
+ return rc;
+}
+
+/**
+ * ecryptfs_read_xattr_region
+ * @page_virt: The vitual address into which to read the xattr data
+ * @ecryptfs_inode: The eCryptfs inode
+ *
+ * Attempts to read the crypto metadata from the extended attribute
+ * region of the lower file.
+ *
+ * Returns zero on success; non-zero on error
+ */
+int ecryptfs_read_xattr_region(char *page_virt, struct inode *ecryptfs_inode)
+{
+ struct dentry *lower_dentry =
+ ecryptfs_inode_to_private(ecryptfs_inode)->lower_file->f_path.dentry;
+ ssize_t size;
+ int rc = 0;
+
+ size = ecryptfs_getxattr_lower(lower_dentry,
+ ecryptfs_inode_to_lower(ecryptfs_inode),
+ ECRYPTFS_XATTR_NAME,
+ page_virt, ECRYPTFS_DEFAULT_EXTENT_SIZE);
+ if (size < 0) {
+ if (unlikely(ecryptfs_verbosity > 0))
+ printk(KERN_INFO "Error attempting to read the [%s] "
+ "xattr from the lower file; return value = "
+ "[%zd]\n", ECRYPTFS_XATTR_NAME, size);
+ rc = -EINVAL;
+ goto out;
+ }
+out:
+ return rc;
+}
+
+int ecryptfs_read_and_validate_xattr_region(struct dentry *dentry,
+ struct inode *inode)
+{
+ u8 file_size[ECRYPTFS_SIZE_AND_MARKER_BYTES];
+ u8 *marker = file_size + ECRYPTFS_FILE_SIZE_BYTES;
+ int rc;
+
+ rc = ecryptfs_getxattr_lower(ecryptfs_dentry_to_lower(dentry),
+ ecryptfs_inode_to_lower(inode),
+ ECRYPTFS_XATTR_NAME, file_size,
+ ECRYPTFS_SIZE_AND_MARKER_BYTES);
+ if (rc < ECRYPTFS_SIZE_AND_MARKER_BYTES)
+ return rc >= 0 ? -EINVAL : rc;
+ rc = ecryptfs_validate_marker(marker);
+ if (!rc)
+ ecryptfs_i_size_init(file_size, inode);
+ return rc;
+}
+
+/**
+ * ecryptfs_read_metadata
+ *
+ * Common entry point for reading file metadata. From here, we could
+ * retrieve the header information from the header region of the file,
+ * the xattr region of the file, or some other repository that is
+ * stored separately from the file itself. The current implementation
+ * supports retrieving the metadata information from the file contents
+ * and from the xattr region.
+ *
+ * Returns zero if valid headers found and parsed; non-zero otherwise
+ */
+int ecryptfs_read_metadata(struct dentry *ecryptfs_dentry)
+{
+ int rc;
+ char *page_virt;
+ struct inode *ecryptfs_inode = d_inode(ecryptfs_dentry);
+ struct ecryptfs_crypt_stat *crypt_stat =
+ &ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat;
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat =
+ &ecryptfs_superblock_to_private(
+ ecryptfs_dentry->d_sb)->mount_crypt_stat;
+
+ ecryptfs_copy_mount_wide_flags_to_inode_flags(crypt_stat,
+ mount_crypt_stat);
+ /* Read the first page from the underlying file */
+ page_virt = kmem_cache_alloc(ecryptfs_header_cache, GFP_USER);
+ if (!page_virt) {
+ rc = -ENOMEM;
+ goto out;
+ }
+ rc = ecryptfs_read_lower(page_virt, 0, crypt_stat->extent_size,
+ ecryptfs_inode);
+ if (rc >= 0)
+ rc = ecryptfs_read_headers_virt(page_virt, crypt_stat,
+ ecryptfs_dentry,
+ ECRYPTFS_VALIDATE_HEADER_SIZE);
+ if (rc) {
+ /* metadata is not in the file header, so try xattrs */
+ memset(page_virt, 0, PAGE_SIZE);
+ rc = ecryptfs_read_xattr_region(page_virt, ecryptfs_inode);
+ if (rc) {
+ printk(KERN_DEBUG "Valid eCryptfs headers not found in "
+ "file header region or xattr region, inode %lu\n",
+ ecryptfs_inode->i_ino);
+ rc = -EINVAL;
+ goto out;
+ }
+ rc = ecryptfs_read_headers_virt(page_virt, crypt_stat,
+ ecryptfs_dentry,
+ ECRYPTFS_DONT_VALIDATE_HEADER_SIZE);
+ if (rc) {
+ printk(KERN_DEBUG "Valid eCryptfs headers not found in "
+ "file xattr region either, inode %lu\n",
+ ecryptfs_inode->i_ino);
+ rc = -EINVAL;
+ }
+ if (crypt_stat->mount_crypt_stat->flags
+ & ECRYPTFS_XATTR_METADATA_ENABLED) {
+ crypt_stat->flags |= ECRYPTFS_METADATA_IN_XATTR;
+ } else {
+ printk(KERN_WARNING "Attempt to access file with "
+ "crypto metadata only in the extended attribute "
+ "region, but eCryptfs was mounted without "
+ "xattr support enabled. eCryptfs will not treat "
+ "this like an encrypted file, inode %lu\n",
+ ecryptfs_inode->i_ino);
+ rc = -EINVAL;
+ }
+ }
+out:
+ if (page_virt) {
+ memset(page_virt, 0, PAGE_SIZE);
+ kmem_cache_free(ecryptfs_header_cache, page_virt);
+ }
+ return rc;
+}
+
+/**
+ * ecryptfs_encrypt_filename - encrypt filename
+ *
+ * CBC-encrypts the filename. We do not want to encrypt the same
+ * filename with the same key and IV, which may happen with hard
+ * links, so we prepend random bits to each filename.
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+static int
+ecryptfs_encrypt_filename(struct ecryptfs_filename *filename,
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat)
+{
+ int rc = 0;
+
+ filename->encrypted_filename = NULL;
+ filename->encrypted_filename_size = 0;
+ if (mount_crypt_stat && (mount_crypt_stat->flags
+ & ECRYPTFS_GLOBAL_ENCFN_USE_MOUNT_FNEK)) {
+ size_t packet_size;
+ size_t remaining_bytes;
+
+ rc = ecryptfs_write_tag_70_packet(
+ NULL, NULL,
+ &filename->encrypted_filename_size,
+ mount_crypt_stat, NULL,
+ filename->filename_size);
+ if (rc) {
+ printk(KERN_ERR "%s: Error attempting to get packet "
+ "size for tag 72; rc = [%d]\n", __func__,
+ rc);
+ filename->encrypted_filename_size = 0;
+ goto out;
+ }
+ filename->encrypted_filename =
+ kmalloc(filename->encrypted_filename_size, GFP_KERNEL);
+ if (!filename->encrypted_filename) {
+ rc = -ENOMEM;
+ goto out;
+ }
+ remaining_bytes = filename->encrypted_filename_size;
+ rc = ecryptfs_write_tag_70_packet(filename->encrypted_filename,
+ &remaining_bytes,
+ &packet_size,
+ mount_crypt_stat,
+ filename->filename,
+ filename->filename_size);
+ if (rc) {
+ printk(KERN_ERR "%s: Error attempting to generate "
+ "tag 70 packet; rc = [%d]\n", __func__,
+ rc);
+ kfree(filename->encrypted_filename);
+ filename->encrypted_filename = NULL;
+ filename->encrypted_filename_size = 0;
+ goto out;
+ }
+ filename->encrypted_filename_size = packet_size;
+ } else {
+ printk(KERN_ERR "%s: No support for requested filename "
+ "encryption method in this release\n", __func__);
+ rc = -EOPNOTSUPP;
+ goto out;
+ }
+out:
+ return rc;
+}
+
+static int ecryptfs_copy_filename(char **copied_name, size_t *copied_name_size,
+ const char *name, size_t name_size)
+{
+ int rc = 0;
+
+ (*copied_name) = kmalloc((name_size + 1), GFP_KERNEL);
+ if (!(*copied_name)) {
+ rc = -ENOMEM;
+ goto out;
+ }
+ memcpy((void *)(*copied_name), (void *)name, name_size);
+ (*copied_name)[(name_size)] = '\0'; /* Only for convenience
+ * in printing out the
+ * string in debug
+ * messages */
+ (*copied_name_size) = name_size;
+out:
+ return rc;
+}
+
+/**
+ * ecryptfs_process_key_cipher - Perform key cipher initialization.
+ * @key_tfm: Crypto context for key material, set by this function
+ * @cipher_name: Name of the cipher
+ * @key_size: Size of the key in bytes
+ *
+ * Returns zero on success. Any crypto_tfm structs allocated here
+ * should be released by other functions, such as on a superblock put
+ * event, regardless of whether this function succeeds for fails.
+ */
+static int
+ecryptfs_process_key_cipher(struct crypto_skcipher **key_tfm,
+ char *cipher_name, size_t *key_size)
+{
+ char dummy_key[ECRYPTFS_MAX_KEY_BYTES];
+ char *full_alg_name = NULL;
+ int rc;
+
+ *key_tfm = NULL;
+ if (*key_size > ECRYPTFS_MAX_KEY_BYTES) {
+ rc = -EINVAL;
+ printk(KERN_ERR "Requested key size is [%zd] bytes; maximum "
+ "allowable is [%d]\n", *key_size, ECRYPTFS_MAX_KEY_BYTES);
+ goto out;
+ }
+ rc = ecryptfs_crypto_api_algify_cipher_name(&full_alg_name, cipher_name,
+ "ecb");
+ if (rc)
+ goto out;
+ *key_tfm = crypto_alloc_skcipher(full_alg_name, 0, CRYPTO_ALG_ASYNC);
+ if (IS_ERR(*key_tfm)) {
+ rc = PTR_ERR(*key_tfm);
+ printk(KERN_ERR "Unable to allocate crypto cipher with name "
+ "[%s]; rc = [%d]\n", full_alg_name, rc);
+ goto out;
+ }
+ crypto_skcipher_set_flags(*key_tfm, CRYPTO_TFM_REQ_WEAK_KEY);
+ if (*key_size == 0)
+ *key_size = crypto_skcipher_default_keysize(*key_tfm);
+ get_random_bytes(dummy_key, *key_size);
+ rc = crypto_skcipher_setkey(*key_tfm, dummy_key, *key_size);
+ if (rc) {
+ printk(KERN_ERR "Error attempting to set key of size [%zd] for "
+ "cipher [%s]; rc = [%d]\n", *key_size, full_alg_name,
+ rc);
+ rc = -EINVAL;
+ goto out;
+ }
+out:
+ kfree(full_alg_name);
+ return rc;
+}
+
+struct kmem_cache *ecryptfs_key_tfm_cache;
+static struct list_head key_tfm_list;
+struct mutex key_tfm_list_mutex;
+
+int __init ecryptfs_init_crypto(void)
+{
+ mutex_init(&key_tfm_list_mutex);
+ INIT_LIST_HEAD(&key_tfm_list);
+ return 0;
+}
+
+/**
+ * ecryptfs_destroy_crypto - free all cached key_tfms on key_tfm_list
+ *
+ * Called only at module unload time
+ */
+int ecryptfs_destroy_crypto(void)
+{
+ struct ecryptfs_key_tfm *key_tfm, *key_tfm_tmp;
+
+ mutex_lock(&key_tfm_list_mutex);
+ list_for_each_entry_safe(key_tfm, key_tfm_tmp, &key_tfm_list,
+ key_tfm_list) {
+ list_del(&key_tfm->key_tfm_list);
+ crypto_free_skcipher(key_tfm->key_tfm);
+ kmem_cache_free(ecryptfs_key_tfm_cache, key_tfm);
+ }
+ mutex_unlock(&key_tfm_list_mutex);
+ return 0;
+}
+
+int
+ecryptfs_add_new_key_tfm(struct ecryptfs_key_tfm **key_tfm, char *cipher_name,
+ size_t key_size)
+{
+ struct ecryptfs_key_tfm *tmp_tfm;
+ int rc = 0;
+
+ BUG_ON(!mutex_is_locked(&key_tfm_list_mutex));
+
+ tmp_tfm = kmem_cache_alloc(ecryptfs_key_tfm_cache, GFP_KERNEL);
+ if (key_tfm)
+ (*key_tfm) = tmp_tfm;
+ if (!tmp_tfm) {
+ rc = -ENOMEM;
+ goto out;
+ }
+ mutex_init(&tmp_tfm->key_tfm_mutex);
+ strncpy(tmp_tfm->cipher_name, cipher_name,
+ ECRYPTFS_MAX_CIPHER_NAME_SIZE);
+ tmp_tfm->cipher_name[ECRYPTFS_MAX_CIPHER_NAME_SIZE] = '\0';
+ tmp_tfm->key_size = key_size;
+ rc = ecryptfs_process_key_cipher(&tmp_tfm->key_tfm,
+ tmp_tfm->cipher_name,
+ &tmp_tfm->key_size);
+ if (rc) {
+ printk(KERN_ERR "Error attempting to initialize key TFM "
+ "cipher with name = [%s]; rc = [%d]\n",
+ tmp_tfm->cipher_name, rc);
+ kmem_cache_free(ecryptfs_key_tfm_cache, tmp_tfm);
+ if (key_tfm)
+ (*key_tfm) = NULL;
+ goto out;
+ }
+ list_add(&tmp_tfm->key_tfm_list, &key_tfm_list);
+out:
+ return rc;
+}
+
+/**
+ * ecryptfs_tfm_exists - Search for existing tfm for cipher_name.
+ * @cipher_name: the name of the cipher to search for
+ * @key_tfm: set to corresponding tfm if found
+ *
+ * Searches for cached key_tfm matching @cipher_name
+ * Must be called with &key_tfm_list_mutex held
+ * Returns 1 if found, with @key_tfm set
+ * Returns 0 if not found, with @key_tfm set to NULL
+ */
+int ecryptfs_tfm_exists(char *cipher_name, struct ecryptfs_key_tfm **key_tfm)
+{
+ struct ecryptfs_key_tfm *tmp_key_tfm;
+
+ BUG_ON(!mutex_is_locked(&key_tfm_list_mutex));
+
+ list_for_each_entry(tmp_key_tfm, &key_tfm_list, key_tfm_list) {
+ if (strcmp(tmp_key_tfm->cipher_name, cipher_name) == 0) {
+ if (key_tfm)
+ (*key_tfm) = tmp_key_tfm;
+ return 1;
+ }
+ }
+ if (key_tfm)
+ (*key_tfm) = NULL;
+ return 0;
+}
+
+/**
+ * ecryptfs_get_tfm_and_mutex_for_cipher_name
+ *
+ * @tfm: set to cached tfm found, or new tfm created
+ * @tfm_mutex: set to mutex for cached tfm found, or new tfm created
+ * @cipher_name: the name of the cipher to search for and/or add
+ *
+ * Sets pointers to @tfm & @tfm_mutex matching @cipher_name.
+ * Searches for cached item first, and creates new if not found.
+ * Returns 0 on success, non-zero if adding new cipher failed
+ */
+int ecryptfs_get_tfm_and_mutex_for_cipher_name(struct crypto_skcipher **tfm,
+ struct mutex **tfm_mutex,
+ char *cipher_name)
+{
+ struct ecryptfs_key_tfm *key_tfm;
+ int rc = 0;
+
+ (*tfm) = NULL;
+ (*tfm_mutex) = NULL;
+
+ mutex_lock(&key_tfm_list_mutex);
+ if (!ecryptfs_tfm_exists(cipher_name, &key_tfm)) {
+ rc = ecryptfs_add_new_key_tfm(&key_tfm, cipher_name, 0);
+ if (rc) {
+ printk(KERN_ERR "Error adding new key_tfm to list; "
+ "rc = [%d]\n", rc);
+ goto out;
+ }
+ }
+ (*tfm) = key_tfm->key_tfm;
+ (*tfm_mutex) = &key_tfm->key_tfm_mutex;
+out:
+ mutex_unlock(&key_tfm_list_mutex);
+ return rc;
+}
+
+/* 64 characters forming a 6-bit target field */
+static unsigned char *portable_filename_chars = ("-.0123456789ABCD"
+ "EFGHIJKLMNOPQRST"
+ "UVWXYZabcdefghij"
+ "klmnopqrstuvwxyz");
+
+/* We could either offset on every reverse map or just pad some 0x00's
+ * at the front here */
+static const unsigned char filename_rev_map[256] = {
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 7 */
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 15 */
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 23 */
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 31 */
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 39 */
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, /* 47 */
+ 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, /* 55 */
+ 0x0A, 0x0B, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 63 */
+ 0x00, 0x0C, 0x0D, 0x0E, 0x0F, 0x10, 0x11, 0x12, /* 71 */
+ 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x1A, /* 79 */
+ 0x1B, 0x1C, 0x1D, 0x1E, 0x1F, 0x20, 0x21, 0x22, /* 87 */
+ 0x23, 0x24, 0x25, 0x00, 0x00, 0x00, 0x00, 0x00, /* 95 */
+ 0x00, 0x26, 0x27, 0x28, 0x29, 0x2A, 0x2B, 0x2C, /* 103 */
+ 0x2D, 0x2E, 0x2F, 0x30, 0x31, 0x32, 0x33, 0x34, /* 111 */
+ 0x35, 0x36, 0x37, 0x38, 0x39, 0x3A, 0x3B, 0x3C, /* 119 */
+ 0x3D, 0x3E, 0x3F /* 123 - 255 initialized to 0x00 */
+};
+
+/**
+ * ecryptfs_encode_for_filename
+ * @dst: Destination location for encoded filename
+ * @dst_size: Size of the encoded filename in bytes
+ * @src: Source location for the filename to encode
+ * @src_size: Size of the source in bytes
+ */
+static void ecryptfs_encode_for_filename(unsigned char *dst, size_t *dst_size,
+ unsigned char *src, size_t src_size)
+{
+ size_t num_blocks;
+ size_t block_num = 0;
+ size_t dst_offset = 0;
+ unsigned char last_block[3];
+
+ if (src_size == 0) {
+ (*dst_size) = 0;
+ goto out;
+ }
+ num_blocks = (src_size / 3);
+ if ((src_size % 3) == 0) {
+ memcpy(last_block, (&src[src_size - 3]), 3);
+ } else {
+ num_blocks++;
+ last_block[2] = 0x00;
+ switch (src_size % 3) {
+ case 1:
+ last_block[0] = src[src_size - 1];
+ last_block[1] = 0x00;
+ break;
+ case 2:
+ last_block[0] = src[src_size - 2];
+ last_block[1] = src[src_size - 1];
+ }
+ }
+ (*dst_size) = (num_blocks * 4);
+ if (!dst)
+ goto out;
+ while (block_num < num_blocks) {
+ unsigned char *src_block;
+ unsigned char dst_block[4];
+
+ if (block_num == (num_blocks - 1))
+ src_block = last_block;
+ else
+ src_block = &src[block_num * 3];
+ dst_block[0] = ((src_block[0] >> 2) & 0x3F);
+ dst_block[1] = (((src_block[0] << 4) & 0x30)
+ | ((src_block[1] >> 4) & 0x0F));
+ dst_block[2] = (((src_block[1] << 2) & 0x3C)
+ | ((src_block[2] >> 6) & 0x03));
+ dst_block[3] = (src_block[2] & 0x3F);
+ dst[dst_offset++] = portable_filename_chars[dst_block[0]];
+ dst[dst_offset++] = portable_filename_chars[dst_block[1]];
+ dst[dst_offset++] = portable_filename_chars[dst_block[2]];
+ dst[dst_offset++] = portable_filename_chars[dst_block[3]];
+ block_num++;
+ }
+out:
+ return;
+}
+
+static size_t ecryptfs_max_decoded_size(size_t encoded_size)
+{
+ /* Not exact; conservatively long. Every block of 4
+ * encoded characters decodes into a block of 3
+ * decoded characters. This segment of code provides
+ * the caller with the maximum amount of allocated
+ * space that @dst will need to point to in a
+ * subsequent call. */
+ return ((encoded_size + 1) * 3) / 4;
+}
+
+/**
+ * ecryptfs_decode_from_filename
+ * @dst: If NULL, this function only sets @dst_size and returns. If
+ * non-NULL, this function decodes the encoded octets in @src
+ * into the memory that @dst points to.
+ * @dst_size: Set to the size of the decoded string.
+ * @src: The encoded set of octets to decode.
+ * @src_size: The size of the encoded set of octets to decode.
+ */
+static void
+ecryptfs_decode_from_filename(unsigned char *dst, size_t *dst_size,
+ const unsigned char *src, size_t src_size)
+{
+ u8 current_bit_offset = 0;
+ size_t src_byte_offset = 0;
+ size_t dst_byte_offset = 0;
+
+ if (!dst) {
+ (*dst_size) = ecryptfs_max_decoded_size(src_size);
+ goto out;
+ }
+ while (src_byte_offset < src_size) {
+ unsigned char src_byte =
+ filename_rev_map[(int)src[src_byte_offset]];
+
+ switch (current_bit_offset) {
+ case 0:
+ dst[dst_byte_offset] = (src_byte << 2);
+ current_bit_offset = 6;
+ break;
+ case 6:
+ dst[dst_byte_offset++] |= (src_byte >> 4);
+ dst[dst_byte_offset] = ((src_byte & 0xF)
+ << 4);
+ current_bit_offset = 4;
+ break;
+ case 4:
+ dst[dst_byte_offset++] |= (src_byte >> 2);
+ dst[dst_byte_offset] = (src_byte << 6);
+ current_bit_offset = 2;
+ break;
+ case 2:
+ dst[dst_byte_offset++] |= (src_byte);
+ current_bit_offset = 0;
+ break;
+ }
+ src_byte_offset++;
+ }
+ (*dst_size) = dst_byte_offset;
+out:
+ return;
+}
+
+/**
+ * ecryptfs_encrypt_and_encode_filename - converts a plaintext file name to cipher text
+ * @crypt_stat: The crypt_stat struct associated with the file anem to encode
+ * @name: The plaintext name
+ * @length: The length of the plaintext
+ * @encoded_name: The encypted name
+ *
+ * Encrypts and encodes a filename into something that constitutes a
+ * valid filename for a filesystem, with printable characters.
+ *
+ * We assume that we have a properly initialized crypto context,
+ * pointed to by crypt_stat->tfm.
+ *
+ * Returns zero on success; non-zero on otherwise
+ */
+int ecryptfs_encrypt_and_encode_filename(
+ char **encoded_name,
+ size_t *encoded_name_size,
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
+ const char *name, size_t name_size)
+{
+ size_t encoded_name_no_prefix_size;
+ int rc = 0;
+
+ (*encoded_name) = NULL;
+ (*encoded_name_size) = 0;
+ if (mount_crypt_stat && (mount_crypt_stat->flags
+ & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES)) {
+ struct ecryptfs_filename *filename;
+
+ filename = kzalloc(sizeof(*filename), GFP_KERNEL);
+ if (!filename) {
+ rc = -ENOMEM;
+ goto out;
+ }
+ filename->filename = (char *)name;
+ filename->filename_size = name_size;
+ rc = ecryptfs_encrypt_filename(filename, mount_crypt_stat);
+ if (rc) {
+ printk(KERN_ERR "%s: Error attempting to encrypt "
+ "filename; rc = [%d]\n", __func__, rc);
+ kfree(filename);
+ goto out;
+ }
+ ecryptfs_encode_for_filename(
+ NULL, &encoded_name_no_prefix_size,
+ filename->encrypted_filename,
+ filename->encrypted_filename_size);
+ if (mount_crypt_stat
+ && (mount_crypt_stat->flags
+ & ECRYPTFS_GLOBAL_ENCFN_USE_MOUNT_FNEK))
+ (*encoded_name_size) =
+ (ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX_SIZE
+ + encoded_name_no_prefix_size);
+ else
+ (*encoded_name_size) =
+ (ECRYPTFS_FEK_ENCRYPTED_FILENAME_PREFIX_SIZE
+ + encoded_name_no_prefix_size);
+ (*encoded_name) = kmalloc((*encoded_name_size) + 1, GFP_KERNEL);
+ if (!(*encoded_name)) {
+ rc = -ENOMEM;
+ kfree(filename->encrypted_filename);
+ kfree(filename);
+ goto out;
+ }
+ if (mount_crypt_stat
+ && (mount_crypt_stat->flags
+ & ECRYPTFS_GLOBAL_ENCFN_USE_MOUNT_FNEK)) {
+ memcpy((*encoded_name),
+ ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX,
+ ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX_SIZE);
+ ecryptfs_encode_for_filename(
+ ((*encoded_name)
+ + ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX_SIZE),
+ &encoded_name_no_prefix_size,
+ filename->encrypted_filename,
+ filename->encrypted_filename_size);
+ (*encoded_name_size) =
+ (ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX_SIZE
+ + encoded_name_no_prefix_size);
+ (*encoded_name)[(*encoded_name_size)] = '\0';
+ } else {
+ rc = -EOPNOTSUPP;
+ }
+ if (rc) {
+ printk(KERN_ERR "%s: Error attempting to encode "
+ "encrypted filename; rc = [%d]\n", __func__,
+ rc);
+ kfree((*encoded_name));
+ (*encoded_name) = NULL;
+ (*encoded_name_size) = 0;
+ }
+ kfree(filename->encrypted_filename);
+ kfree(filename);
+ } else {
+ rc = ecryptfs_copy_filename(encoded_name,
+ encoded_name_size,
+ name, name_size);
+ }
+out:
+ return rc;
+}
+
+static bool is_dot_dotdot(const char *name, size_t name_size)
+{
+ if (name_size == 1 && name[0] == '.')
+ return true;
+ else if (name_size == 2 && name[0] == '.' && name[1] == '.')
+ return true;
+
+ return false;
+}
+
+/**
+ * ecryptfs_decode_and_decrypt_filename - converts the encoded cipher text name to decoded plaintext
+ * @plaintext_name: The plaintext name
+ * @plaintext_name_size: The plaintext name size
+ * @ecryptfs_dir_dentry: eCryptfs directory dentry
+ * @name: The filename in cipher text
+ * @name_size: The cipher text name size
+ *
+ * Decrypts and decodes the filename.
+ *
+ * Returns zero on error; non-zero otherwise
+ */
+int ecryptfs_decode_and_decrypt_filename(char **plaintext_name,
+ size_t *plaintext_name_size,
+ struct super_block *sb,
+ const char *name, size_t name_size)
+{
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat =
+ &ecryptfs_superblock_to_private(sb)->mount_crypt_stat;
+ char *decoded_name;
+ size_t decoded_name_size;
+ size_t packet_size;
+ int rc = 0;
+
+ if ((mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES) &&
+ !(mount_crypt_stat->flags & ECRYPTFS_ENCRYPTED_VIEW_ENABLED)) {
+ if (is_dot_dotdot(name, name_size)) {
+ rc = ecryptfs_copy_filename(plaintext_name,
+ plaintext_name_size,
+ name, name_size);
+ goto out;
+ }
+
+ if (name_size <= ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX_SIZE ||
+ strncmp(name, ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX,
+ ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX_SIZE)) {
+ rc = -EINVAL;
+ goto out;
+ }
+
+ name += ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX_SIZE;
+ name_size -= ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX_SIZE;
+ ecryptfs_decode_from_filename(NULL, &decoded_name_size,
+ name, name_size);
+ decoded_name = kmalloc(decoded_name_size, GFP_KERNEL);
+ if (!decoded_name) {
+ rc = -ENOMEM;
+ goto out;
+ }
+ ecryptfs_decode_from_filename(decoded_name, &decoded_name_size,
+ name, name_size);
+ rc = ecryptfs_parse_tag_70_packet(plaintext_name,
+ plaintext_name_size,
+ &packet_size,
+ mount_crypt_stat,
+ decoded_name,
+ decoded_name_size);
+ if (rc) {
+ ecryptfs_printk(KERN_DEBUG,
+ "%s: Could not parse tag 70 packet from filename\n",
+ __func__);
+ goto out_free;
+ }
+ } else {
+ rc = ecryptfs_copy_filename(plaintext_name,
+ plaintext_name_size,
+ name, name_size);
+ goto out;
+ }
+out_free:
+ kfree(decoded_name);
+out:
+ return rc;
+}
+
+#define ENC_NAME_MAX_BLOCKLEN_8_OR_16 143
+
+int ecryptfs_set_f_namelen(long *namelen, long lower_namelen,
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat)
+{
+ struct crypto_skcipher *tfm;
+ struct mutex *tfm_mutex;
+ size_t cipher_blocksize;
+ int rc;
+
+ if (!(mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES)) {
+ (*namelen) = lower_namelen;
+ return 0;
+ }
+
+ rc = ecryptfs_get_tfm_and_mutex_for_cipher_name(&tfm, &tfm_mutex,
+ mount_crypt_stat->global_default_fn_cipher_name);
+ if (unlikely(rc)) {
+ (*namelen) = 0;
+ return rc;
+ }
+
+ mutex_lock(tfm_mutex);
+ cipher_blocksize = crypto_skcipher_blocksize(tfm);
+ mutex_unlock(tfm_mutex);
+
+ /* Return an exact amount for the common cases */
+ if (lower_namelen == NAME_MAX
+ && (cipher_blocksize == 8 || cipher_blocksize == 16)) {
+ (*namelen) = ENC_NAME_MAX_BLOCKLEN_8_OR_16;
+ return 0;
+ }
+
+ /* Return a safe estimate for the uncommon cases */
+ (*namelen) = lower_namelen;
+ (*namelen) -= ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX_SIZE;
+ /* Since this is the max decoded size, subtract 1 "decoded block" len */
+ (*namelen) = ecryptfs_max_decoded_size(*namelen) - 3;
+ (*namelen) -= ECRYPTFS_TAG_70_MAX_METADATA_SIZE;
+ (*namelen) -= ECRYPTFS_FILENAME_MIN_RANDOM_PREPEND_BYTES;
+ /* Worst case is that the filename is padded nearly a full block size */
+ (*namelen) -= cipher_blocksize - 1;
+
+ if ((*namelen) < 0)
+ (*namelen) = 0;
+
+ return 0;
+}
diff --git a/fs/ecryptfs/debug.c b/fs/ecryptfs/debug.c
new file mode 100644
index 0000000..3d2bdf5
--- /dev/null
+++ b/fs/ecryptfs/debug.c
@@ -0,0 +1,121 @@
+/**
+ * eCryptfs: Linux filesystem encryption layer
+ * Functions only useful for debugging.
+ *
+ * Copyright (C) 2006 International Business Machines Corp.
+ * Author(s): Michael A. Halcrow <mahalcro@us.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ */
+
+#include "ecryptfs_kernel.h"
+
+/**
+ * ecryptfs_dump_auth_tok - debug function to print auth toks
+ *
+ * This function will print the contents of an ecryptfs authentication
+ * token.
+ */
+void ecryptfs_dump_auth_tok(struct ecryptfs_auth_tok *auth_tok)
+{
+ char salt[ECRYPTFS_SALT_SIZE * 2 + 1];
+ char sig[ECRYPTFS_SIG_SIZE_HEX + 1];
+
+ ecryptfs_printk(KERN_DEBUG, "Auth tok at mem loc [%p]:\n",
+ auth_tok);
+ if (auth_tok->flags & ECRYPTFS_PRIVATE_KEY) {
+ ecryptfs_printk(KERN_DEBUG, " * private key type\n");
+ } else {
+ ecryptfs_printk(KERN_DEBUG, " * passphrase type\n");
+ ecryptfs_to_hex(salt, auth_tok->token.password.salt,
+ ECRYPTFS_SALT_SIZE);
+ salt[ECRYPTFS_SALT_SIZE * 2] = '\0';
+ ecryptfs_printk(KERN_DEBUG, " * salt = [%s]\n", salt);
+ if (auth_tok->token.password.flags &
+ ECRYPTFS_PERSISTENT_PASSWORD) {
+ ecryptfs_printk(KERN_DEBUG, " * persistent\n");
+ }
+ memcpy(sig, auth_tok->token.password.signature,
+ ECRYPTFS_SIG_SIZE_HEX);
+ sig[ECRYPTFS_SIG_SIZE_HEX] = '\0';
+ ecryptfs_printk(KERN_DEBUG, " * signature = [%s]\n", sig);
+ }
+ ecryptfs_printk(KERN_DEBUG, " * session_key.flags = [0x%x]\n",
+ auth_tok->session_key.flags);
+ if (auth_tok->session_key.flags
+ & ECRYPTFS_USERSPACE_SHOULD_TRY_TO_DECRYPT)
+ ecryptfs_printk(KERN_DEBUG,
+ " * Userspace decrypt request set\n");
+ if (auth_tok->session_key.flags
+ & ECRYPTFS_USERSPACE_SHOULD_TRY_TO_ENCRYPT)
+ ecryptfs_printk(KERN_DEBUG,
+ " * Userspace encrypt request set\n");
+ if (auth_tok->session_key.flags & ECRYPTFS_CONTAINS_DECRYPTED_KEY) {
+ ecryptfs_printk(KERN_DEBUG, " * Contains decrypted key\n");
+ ecryptfs_printk(KERN_DEBUG,
+ " * session_key.decrypted_key_size = [0x%x]\n",
+ auth_tok->session_key.decrypted_key_size);
+ ecryptfs_printk(KERN_DEBUG, " * Decrypted session key "
+ "dump:\n");
+ if (ecryptfs_verbosity > 0)
+ ecryptfs_dump_hex(auth_tok->session_key.decrypted_key,
+ ECRYPTFS_DEFAULT_KEY_BYTES);
+ }
+ if (auth_tok->session_key.flags & ECRYPTFS_CONTAINS_ENCRYPTED_KEY) {
+ ecryptfs_printk(KERN_DEBUG, " * Contains encrypted key\n");
+ ecryptfs_printk(KERN_DEBUG,
+ " * session_key.encrypted_key_size = [0x%x]\n",
+ auth_tok->session_key.encrypted_key_size);
+ ecryptfs_printk(KERN_DEBUG, " * Encrypted session key "
+ "dump:\n");
+ if (ecryptfs_verbosity > 0)
+ ecryptfs_dump_hex(auth_tok->session_key.encrypted_key,
+ auth_tok->session_key.
+ encrypted_key_size);
+ }
+}
+
+/**
+ * ecryptfs_dump_hex - debug hex printer
+ * @data: string of bytes to be printed
+ * @bytes: number of bytes to print
+ *
+ * Dump hexadecimal representation of char array
+ */
+void ecryptfs_dump_hex(char *data, int bytes)
+{
+ int i = 0;
+ int add_newline = 1;
+
+ if (ecryptfs_verbosity < 1)
+ return;
+ if (bytes != 0) {
+ printk(KERN_DEBUG "0x%.2x.", (unsigned char)data[i]);
+ i++;
+ }
+ while (i < bytes) {
+ printk("0x%.2x.", (unsigned char)data[i]);
+ i++;
+ if (i % 16 == 0) {
+ printk("\n");
+ add_newline = 0;
+ } else
+ add_newline = 1;
+ }
+ if (add_newline)
+ printk("\n");
+}
+
diff --git a/fs/ecryptfs/dentry.c b/fs/ecryptfs/dentry.c
new file mode 100644
index 0000000..63cd2c1
--- /dev/null
+++ b/fs/ecryptfs/dentry.c
@@ -0,0 +1,92 @@
+/**
+ * eCryptfs: Linux filesystem encryption layer
+ *
+ * Copyright (C) 1997-2003 Erez Zadok
+ * Copyright (C) 2001-2003 Stony Brook University
+ * Copyright (C) 2004-2006 International Business Machines Corp.
+ * Author(s): Michael A. Halcrow <mahalcro@us.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ */
+
+#include <linux/dcache.h>
+#include <linux/namei.h>
+#include <linux/mount.h>
+#include <linux/fs_stack.h>
+#include <linux/slab.h>
+#include "ecryptfs_kernel.h"
+
+/**
+ * ecryptfs_d_revalidate - revalidate an ecryptfs dentry
+ * @dentry: The ecryptfs dentry
+ * @flags: lookup flags
+ *
+ * Called when the VFS needs to revalidate a dentry. This
+ * is called whenever a name lookup finds a dentry in the
+ * dcache. Most filesystems leave this as NULL, because all their
+ * dentries in the dcache are valid.
+ *
+ * Returns 1 if valid, 0 otherwise.
+ *
+ */
+static int ecryptfs_d_revalidate(struct dentry *dentry, unsigned int flags)
+{
+ struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
+ int rc = 1;
+
+ if (flags & LOOKUP_RCU)
+ return -ECHILD;
+
+ if (lower_dentry->d_flags & DCACHE_OP_REVALIDATE)
+ rc = lower_dentry->d_op->d_revalidate(lower_dentry, flags);
+
+ if (d_really_is_positive(dentry)) {
+ struct inode *inode = d_inode(dentry);
+
+ fsstack_copy_attr_all(inode, ecryptfs_inode_to_lower(inode));
+ if (!inode->i_nlink)
+ return 0;
+ }
+ return rc;
+}
+
+struct kmem_cache *ecryptfs_dentry_info_cache;
+
+static void ecryptfs_dentry_free_rcu(struct rcu_head *head)
+{
+ kmem_cache_free(ecryptfs_dentry_info_cache,
+ container_of(head, struct ecryptfs_dentry_info, rcu));
+}
+
+/**
+ * ecryptfs_d_release
+ * @dentry: The ecryptfs dentry
+ *
+ * Called when a dentry is really deallocated.
+ */
+static void ecryptfs_d_release(struct dentry *dentry)
+{
+ struct ecryptfs_dentry_info *p = dentry->d_fsdata;
+ if (p) {
+ path_put(&p->lower_path);
+ call_rcu(&p->rcu, ecryptfs_dentry_free_rcu);
+ }
+}
+
+const struct dentry_operations ecryptfs_dops = {
+ .d_revalidate = ecryptfs_d_revalidate,
+ .d_release = ecryptfs_d_release,
+};
diff --git a/fs/ecryptfs/ecryptfs_kernel.h b/fs/ecryptfs/ecryptfs_kernel.h
new file mode 100644
index 0000000..e74cb2a
--- /dev/null
+++ b/fs/ecryptfs/ecryptfs_kernel.h
@@ -0,0 +1,736 @@
+/**
+ * eCryptfs: Linux filesystem encryption layer
+ * Kernel declarations.
+ *
+ * Copyright (C) 1997-2003 Erez Zadok
+ * Copyright (C) 2001-2003 Stony Brook University
+ * Copyright (C) 2004-2008 International Business Machines Corp.
+ * Author(s): Michael A. Halcrow <mahalcro@us.ibm.com>
+ * Trevor S. Highland <trevor.highland@gmail.com>
+ * Tyler Hicks <tyhicks@ou.edu>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ */
+
+#ifndef ECRYPTFS_KERNEL_H
+#define ECRYPTFS_KERNEL_H
+
+#include <crypto/skcipher.h>
+#include <keys/user-type.h>
+#include <keys/encrypted-type.h>
+#include <linux/kernel.h>
+#include <linux/fs.h>
+#include <linux/fs_stack.h>
+#include <linux/namei.h>
+#include <linux/scatterlist.h>
+#include <linux/hash.h>
+#include <linux/nsproxy.h>
+#include <linux/backing-dev.h>
+#include <linux/ecryptfs.h>
+
+#define ECRYPTFS_DEFAULT_IV_BYTES 16
+#define ECRYPTFS_DEFAULT_EXTENT_SIZE 4096
+#define ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE 8192
+#define ECRYPTFS_DEFAULT_MSG_CTX_ELEMS 32
+#define ECRYPTFS_DEFAULT_SEND_TIMEOUT HZ
+#define ECRYPTFS_MAX_MSG_CTX_TTL (HZ*3)
+#define ECRYPTFS_DEFAULT_NUM_USERS 4
+#define ECRYPTFS_MAX_NUM_USERS 32768
+#define ECRYPTFS_XATTR_NAME "user.ecryptfs"
+
+void ecryptfs_dump_auth_tok(struct ecryptfs_auth_tok *auth_tok);
+static inline void
+ecryptfs_to_hex(char *dst, char *src, size_t src_size)
+{
+ char *end = bin2hex(dst, src, src_size);
+ *end = '\0';
+}
+
+extern void ecryptfs_from_hex(char *dst, char *src, int dst_size);
+
+struct ecryptfs_key_record {
+ unsigned char type;
+ size_t enc_key_size;
+ unsigned char sig[ECRYPTFS_SIG_SIZE];
+ unsigned char enc_key[ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES];
+};
+
+struct ecryptfs_auth_tok_list {
+ struct ecryptfs_auth_tok *auth_tok;
+ struct list_head list;
+};
+
+struct ecryptfs_crypt_stat;
+struct ecryptfs_mount_crypt_stat;
+
+struct ecryptfs_page_crypt_context {
+ struct page *page;
+#define ECRYPTFS_PREPARE_COMMIT_MODE 0
+#define ECRYPTFS_WRITEPAGE_MODE 1
+ unsigned int mode;
+ union {
+ struct file *lower_file;
+ struct writeback_control *wbc;
+ } param;
+};
+
+#if defined(CONFIG_ENCRYPTED_KEYS) || defined(CONFIG_ENCRYPTED_KEYS_MODULE)
+static inline struct ecryptfs_auth_tok *
+ecryptfs_get_encrypted_key_payload_data(struct key *key)
+{
+ struct encrypted_key_payload *payload;
+
+ if (key->type != &key_type_encrypted)
+ return NULL;
+
+ payload = key->payload.data[0];
+ if (!payload)
+ return ERR_PTR(-EKEYREVOKED);
+
+ return (struct ecryptfs_auth_tok *)payload->payload_data;
+}
+
+static inline struct key *ecryptfs_get_encrypted_key(char *sig)
+{
+ return request_key(&key_type_encrypted, sig, NULL);
+}
+
+#else
+static inline struct ecryptfs_auth_tok *
+ecryptfs_get_encrypted_key_payload_data(struct key *key)
+{
+ return NULL;
+}
+
+static inline struct key *ecryptfs_get_encrypted_key(char *sig)
+{
+ return ERR_PTR(-ENOKEY);
+}
+
+#endif /* CONFIG_ENCRYPTED_KEYS */
+
+static inline struct ecryptfs_auth_tok *
+ecryptfs_get_key_payload_data(struct key *key)
+{
+ struct ecryptfs_auth_tok *auth_tok;
+ struct user_key_payload *ukp;
+
+ auth_tok = ecryptfs_get_encrypted_key_payload_data(key);
+ if (auth_tok)
+ return auth_tok;
+
+ ukp = user_key_payload_locked(key);
+ if (!ukp)
+ return ERR_PTR(-EKEYREVOKED);
+
+ return (struct ecryptfs_auth_tok *)ukp->data;
+}
+
+#define ECRYPTFS_MAX_KEYSET_SIZE 1024
+#define ECRYPTFS_MAX_CIPHER_NAME_SIZE 31
+#define ECRYPTFS_MAX_NUM_ENC_KEYS 64
+#define ECRYPTFS_MAX_IV_BYTES 16 /* 128 bits */
+#define ECRYPTFS_SALT_BYTES 2
+#define MAGIC_ECRYPTFS_MARKER 0x3c81b7f5
+#define MAGIC_ECRYPTFS_MARKER_SIZE_BYTES 8 /* 4*2 */
+#define ECRYPTFS_FILE_SIZE_BYTES (sizeof(u64))
+#define ECRYPTFS_SIZE_AND_MARKER_BYTES (ECRYPTFS_FILE_SIZE_BYTES \
+ + MAGIC_ECRYPTFS_MARKER_SIZE_BYTES)
+#define ECRYPTFS_DEFAULT_CIPHER "aes"
+#define ECRYPTFS_DEFAULT_KEY_BYTES 16
+#define ECRYPTFS_DEFAULT_HASH "md5"
+#define ECRYPTFS_TAG_70_DIGEST ECRYPTFS_DEFAULT_HASH
+#define ECRYPTFS_TAG_1_PACKET_TYPE 0x01
+#define ECRYPTFS_TAG_3_PACKET_TYPE 0x8C
+#define ECRYPTFS_TAG_11_PACKET_TYPE 0xED
+#define ECRYPTFS_TAG_64_PACKET_TYPE 0x40
+#define ECRYPTFS_TAG_65_PACKET_TYPE 0x41
+#define ECRYPTFS_TAG_66_PACKET_TYPE 0x42
+#define ECRYPTFS_TAG_67_PACKET_TYPE 0x43
+#define ECRYPTFS_TAG_70_PACKET_TYPE 0x46 /* FNEK-encrypted filename
+ * as dentry name */
+#define ECRYPTFS_TAG_71_PACKET_TYPE 0x47 /* FNEK-encrypted filename in
+ * metadata */
+#define ECRYPTFS_TAG_72_PACKET_TYPE 0x48 /* FEK-encrypted filename as
+ * dentry name */
+#define ECRYPTFS_TAG_73_PACKET_TYPE 0x49 /* FEK-encrypted filename as
+ * metadata */
+#define ECRYPTFS_MIN_PKT_LEN_SIZE 1 /* Min size to specify packet length */
+#define ECRYPTFS_MAX_PKT_LEN_SIZE 2 /* Pass at least this many bytes to
+ * ecryptfs_parse_packet_length() and
+ * ecryptfs_write_packet_length()
+ */
+/* Constraint: ECRYPTFS_FILENAME_MIN_RANDOM_PREPEND_BYTES >=
+ * ECRYPTFS_MAX_IV_BYTES */
+#define ECRYPTFS_FILENAME_MIN_RANDOM_PREPEND_BYTES 16
+#define ECRYPTFS_NON_NULL 0x42 /* A reasonable substitute for NULL */
+#define MD5_DIGEST_SIZE 16
+#define ECRYPTFS_TAG_70_DIGEST_SIZE MD5_DIGEST_SIZE
+#define ECRYPTFS_TAG_70_MIN_METADATA_SIZE (1 + ECRYPTFS_MIN_PKT_LEN_SIZE \
+ + ECRYPTFS_SIG_SIZE + 1 + 1)
+#define ECRYPTFS_TAG_70_MAX_METADATA_SIZE (1 + ECRYPTFS_MAX_PKT_LEN_SIZE \
+ + ECRYPTFS_SIG_SIZE + 1 + 1)
+#define ECRYPTFS_FEK_ENCRYPTED_FILENAME_PREFIX "ECRYPTFS_FEK_ENCRYPTED."
+#define ECRYPTFS_FEK_ENCRYPTED_FILENAME_PREFIX_SIZE 23
+#define ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX "ECRYPTFS_FNEK_ENCRYPTED."
+#define ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX_SIZE 24
+#define ECRYPTFS_ENCRYPTED_DENTRY_NAME_LEN (18 + 1 + 4 + 1 + 32)
+
+#ifdef CONFIG_ECRYPT_FS_MESSAGING
+# define ECRYPTFS_VERSIONING_MASK_MESSAGING (ECRYPTFS_VERSIONING_DEVMISC \
+ | ECRYPTFS_VERSIONING_PUBKEY)
+#else
+# define ECRYPTFS_VERSIONING_MASK_MESSAGING 0
+#endif
+
+#define ECRYPTFS_VERSIONING_MASK (ECRYPTFS_VERSIONING_PASSPHRASE \
+ | ECRYPTFS_VERSIONING_PLAINTEXT_PASSTHROUGH \
+ | ECRYPTFS_VERSIONING_XATTR \
+ | ECRYPTFS_VERSIONING_MULTKEY \
+ | ECRYPTFS_VERSIONING_MASK_MESSAGING \
+ | ECRYPTFS_VERSIONING_FILENAME_ENCRYPTION)
+struct ecryptfs_key_sig {
+ struct list_head crypt_stat_list;
+ char keysig[ECRYPTFS_SIG_SIZE_HEX + 1];
+};
+
+struct ecryptfs_filename {
+ struct list_head crypt_stat_list;
+#define ECRYPTFS_FILENAME_CONTAINS_DECRYPTED 0x00000001
+ u32 flags;
+ u32 seq_no;
+ char *filename;
+ char *encrypted_filename;
+ size_t filename_size;
+ size_t encrypted_filename_size;
+ char fnek_sig[ECRYPTFS_SIG_SIZE_HEX];
+ char dentry_name[ECRYPTFS_ENCRYPTED_DENTRY_NAME_LEN + 1];
+};
+
+/**
+ * This is the primary struct associated with each encrypted file.
+ *
+ * TODO: cache align/pack?
+ */
+struct ecryptfs_crypt_stat {
+#define ECRYPTFS_STRUCT_INITIALIZED 0x00000001
+#define ECRYPTFS_POLICY_APPLIED 0x00000002
+#define ECRYPTFS_ENCRYPTED 0x00000004
+#define ECRYPTFS_SECURITY_WARNING 0x00000008
+#define ECRYPTFS_ENABLE_HMAC 0x00000010
+#define ECRYPTFS_ENCRYPT_IV_PAGES 0x00000020
+#define ECRYPTFS_KEY_VALID 0x00000040
+#define ECRYPTFS_METADATA_IN_XATTR 0x00000080
+#define ECRYPTFS_VIEW_AS_ENCRYPTED 0x00000100
+#define ECRYPTFS_KEY_SET 0x00000200
+#define ECRYPTFS_ENCRYPT_FILENAMES 0x00000400
+#define ECRYPTFS_ENCFN_USE_MOUNT_FNEK 0x00000800
+#define ECRYPTFS_ENCFN_USE_FEK 0x00001000
+#define ECRYPTFS_UNLINK_SIGS 0x00002000
+#define ECRYPTFS_I_SIZE_INITIALIZED 0x00004000
+ u32 flags;
+ unsigned int file_version;
+ size_t iv_bytes;
+ size_t metadata_size;
+ size_t extent_size; /* Data extent size; default is 4096 */
+ size_t key_size;
+ size_t extent_shift;
+ unsigned int extent_mask;
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
+ struct crypto_skcipher *tfm;
+ struct crypto_shash *hash_tfm; /* Crypto context for generating
+ * the initialization vectors */
+ unsigned char cipher[ECRYPTFS_MAX_CIPHER_NAME_SIZE + 1];
+ unsigned char key[ECRYPTFS_MAX_KEY_BYTES];
+ unsigned char root_iv[ECRYPTFS_MAX_IV_BYTES];
+ struct list_head keysig_list;
+ struct mutex keysig_list_mutex;
+ struct mutex cs_tfm_mutex;
+ struct mutex cs_mutex;
+};
+
+/* inode private data. */
+struct ecryptfs_inode_info {
+ struct inode vfs_inode;
+ struct inode *wii_inode;
+ struct mutex lower_file_mutex;
+ atomic_t lower_file_count;
+ struct file *lower_file;
+ struct ecryptfs_crypt_stat crypt_stat;
+};
+
+/* dentry private data. Each dentry must keep track of a lower
+ * vfsmount too. */
+struct ecryptfs_dentry_info {
+ struct path lower_path;
+ union {
+ struct ecryptfs_crypt_stat *crypt_stat;
+ struct rcu_head rcu;
+ };
+};
+
+/**
+ * ecryptfs_global_auth_tok - A key used to encrypt all new files under the mountpoint
+ * @flags: Status flags
+ * @mount_crypt_stat_list: These auth_toks hang off the mount-wide
+ * cryptographic context. Every time a new
+ * inode comes into existence, eCryptfs copies
+ * the auth_toks on that list to the set of
+ * auth_toks on the inode's crypt_stat
+ * @global_auth_tok_key: The key from the user's keyring for the sig
+ * @global_auth_tok: The key contents
+ * @sig: The key identifier
+ *
+ * ecryptfs_global_auth_tok structs refer to authentication token keys
+ * in the user keyring that apply to newly created files. A list of
+ * these objects hangs off of the mount_crypt_stat struct for any
+ * given eCryptfs mount. This struct maintains a reference to both the
+ * key contents and the key itself so that the key can be put on
+ * unmount.
+ */
+struct ecryptfs_global_auth_tok {
+#define ECRYPTFS_AUTH_TOK_INVALID 0x00000001
+#define ECRYPTFS_AUTH_TOK_FNEK 0x00000002
+ u32 flags;
+ struct list_head mount_crypt_stat_list;
+ struct key *global_auth_tok_key;
+ unsigned char sig[ECRYPTFS_SIG_SIZE_HEX + 1];
+};
+
+/**
+ * ecryptfs_key_tfm - Persistent key tfm
+ * @key_tfm: crypto API handle to the key
+ * @key_size: Key size in bytes
+ * @key_tfm_mutex: Mutex to ensure only one operation in eCryptfs is
+ * using the persistent TFM at any point in time
+ * @key_tfm_list: Handle to hang this off the module-wide TFM list
+ * @cipher_name: String name for the cipher for this TFM
+ *
+ * Typically, eCryptfs will use the same ciphers repeatedly throughout
+ * the course of its operations. In order to avoid unnecessarily
+ * destroying and initializing the same cipher repeatedly, eCryptfs
+ * keeps a list of crypto API contexts around to use when needed.
+ */
+struct ecryptfs_key_tfm {
+ struct crypto_skcipher *key_tfm;
+ size_t key_size;
+ struct mutex key_tfm_mutex;
+ struct list_head key_tfm_list;
+ unsigned char cipher_name[ECRYPTFS_MAX_CIPHER_NAME_SIZE + 1];
+};
+
+extern struct mutex key_tfm_list_mutex;
+
+/**
+ * This struct is to enable a mount-wide passphrase/salt combo. This
+ * is more or less a stopgap to provide similar functionality to other
+ * crypto filesystems like EncFS or CFS until full policy support is
+ * implemented in eCryptfs.
+ */
+struct ecryptfs_mount_crypt_stat {
+ /* Pointers to memory we do not own, do not free these */
+#define ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED 0x00000001
+#define ECRYPTFS_XATTR_METADATA_ENABLED 0x00000002
+#define ECRYPTFS_ENCRYPTED_VIEW_ENABLED 0x00000004
+#define ECRYPTFS_MOUNT_CRYPT_STAT_INITIALIZED 0x00000008
+#define ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES 0x00000010
+#define ECRYPTFS_GLOBAL_ENCFN_USE_MOUNT_FNEK 0x00000020
+#define ECRYPTFS_GLOBAL_ENCFN_USE_FEK 0x00000040
+#define ECRYPTFS_GLOBAL_MOUNT_AUTH_TOK_ONLY 0x00000080
+ u32 flags;
+ struct list_head global_auth_tok_list;
+ struct mutex global_auth_tok_list_mutex;
+ size_t global_default_cipher_key_size;
+ size_t global_default_fn_cipher_key_bytes;
+ unsigned char global_default_cipher_name[ECRYPTFS_MAX_CIPHER_NAME_SIZE
+ + 1];
+ unsigned char global_default_fn_cipher_name[
+ ECRYPTFS_MAX_CIPHER_NAME_SIZE + 1];
+ char global_default_fnek_sig[ECRYPTFS_SIG_SIZE_HEX + 1];
+};
+
+/* superblock private data. */
+struct ecryptfs_sb_info {
+ struct super_block *wsi_sb;
+ struct ecryptfs_mount_crypt_stat mount_crypt_stat;
+};
+
+/* file private data. */
+struct ecryptfs_file_info {
+ struct file *wfi_file;
+ struct ecryptfs_crypt_stat *crypt_stat;
+};
+
+/* auth_tok <=> encrypted_session_key mappings */
+struct ecryptfs_auth_tok_list_item {
+ unsigned char encrypted_session_key[ECRYPTFS_MAX_KEY_BYTES];
+ struct list_head list;
+ struct ecryptfs_auth_tok auth_tok;
+};
+
+struct ecryptfs_message {
+ /* Can never be greater than ecryptfs_message_buf_len */
+ /* Used to find the parent msg_ctx */
+ /* Inherits from msg_ctx->index */
+ u32 index;
+ u32 data_len;
+ u8 data[];
+};
+
+struct ecryptfs_msg_ctx {
+#define ECRYPTFS_MSG_CTX_STATE_FREE 0x01
+#define ECRYPTFS_MSG_CTX_STATE_PENDING 0x02
+#define ECRYPTFS_MSG_CTX_STATE_DONE 0x03
+#define ECRYPTFS_MSG_CTX_STATE_NO_REPLY 0x04
+ u8 state;
+#define ECRYPTFS_MSG_HELO 100
+#define ECRYPTFS_MSG_QUIT 101
+#define ECRYPTFS_MSG_REQUEST 102
+#define ECRYPTFS_MSG_RESPONSE 103
+ u8 type;
+ u32 index;
+ /* Counter converts to a sequence number. Each message sent
+ * out for which we expect a response has an associated
+ * sequence number. The response must have the same sequence
+ * number as the counter for the msg_stc for the message to be
+ * valid. */
+ u32 counter;
+ size_t msg_size;
+ struct ecryptfs_message *msg;
+ struct task_struct *task;
+ struct list_head node;
+ struct list_head daemon_out_list;
+ struct mutex mux;
+};
+
+struct ecryptfs_daemon {
+#define ECRYPTFS_DAEMON_IN_READ 0x00000001
+#define ECRYPTFS_DAEMON_IN_POLL 0x00000002
+#define ECRYPTFS_DAEMON_ZOMBIE 0x00000004
+#define ECRYPTFS_DAEMON_MISCDEV_OPEN 0x00000008
+ u32 flags;
+ u32 num_queued_msg_ctx;
+ struct file *file;
+ struct mutex mux;
+ struct list_head msg_ctx_out_queue;
+ wait_queue_head_t wait;
+ struct hlist_node euid_chain;
+};
+
+#ifdef CONFIG_ECRYPT_FS_MESSAGING
+extern struct mutex ecryptfs_daemon_hash_mux;
+#endif
+
+static inline size_t
+ecryptfs_lower_header_size(struct ecryptfs_crypt_stat *crypt_stat)
+{
+ if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR)
+ return 0;
+ return crypt_stat->metadata_size;
+}
+
+static inline struct ecryptfs_file_info *
+ecryptfs_file_to_private(struct file *file)
+{
+ return file->private_data;
+}
+
+static inline void
+ecryptfs_set_file_private(struct file *file,
+ struct ecryptfs_file_info *file_info)
+{
+ file->private_data = file_info;
+}
+
+static inline struct file *ecryptfs_file_to_lower(struct file *file)
+{
+ return ((struct ecryptfs_file_info *)file->private_data)->wfi_file;
+}
+
+static inline void
+ecryptfs_set_file_lower(struct file *file, struct file *lower_file)
+{
+ ((struct ecryptfs_file_info *)file->private_data)->wfi_file =
+ lower_file;
+}
+
+static inline struct ecryptfs_inode_info *
+ecryptfs_inode_to_private(struct inode *inode)
+{
+ return container_of(inode, struct ecryptfs_inode_info, vfs_inode);
+}
+
+static inline struct inode *ecryptfs_inode_to_lower(struct inode *inode)
+{
+ return ecryptfs_inode_to_private(inode)->wii_inode;
+}
+
+static inline void
+ecryptfs_set_inode_lower(struct inode *inode, struct inode *lower_inode)
+{
+ ecryptfs_inode_to_private(inode)->wii_inode = lower_inode;
+}
+
+static inline struct ecryptfs_sb_info *
+ecryptfs_superblock_to_private(struct super_block *sb)
+{
+ return (struct ecryptfs_sb_info *)sb->s_fs_info;
+}
+
+static inline void
+ecryptfs_set_superblock_private(struct super_block *sb,
+ struct ecryptfs_sb_info *sb_info)
+{
+ sb->s_fs_info = sb_info;
+}
+
+static inline struct super_block *
+ecryptfs_superblock_to_lower(struct super_block *sb)
+{
+ return ((struct ecryptfs_sb_info *)sb->s_fs_info)->wsi_sb;
+}
+
+static inline void
+ecryptfs_set_superblock_lower(struct super_block *sb,
+ struct super_block *lower_sb)
+{
+ ((struct ecryptfs_sb_info *)sb->s_fs_info)->wsi_sb = lower_sb;
+}
+
+static inline struct ecryptfs_dentry_info *
+ecryptfs_dentry_to_private(struct dentry *dentry)
+{
+ return (struct ecryptfs_dentry_info *)dentry->d_fsdata;
+}
+
+static inline void
+ecryptfs_set_dentry_private(struct dentry *dentry,
+ struct ecryptfs_dentry_info *dentry_info)
+{
+ dentry->d_fsdata = dentry_info;
+}
+
+static inline struct dentry *
+ecryptfs_dentry_to_lower(struct dentry *dentry)
+{
+ return ((struct ecryptfs_dentry_info *)dentry->d_fsdata)->lower_path.dentry;
+}
+
+static inline struct vfsmount *
+ecryptfs_dentry_to_lower_mnt(struct dentry *dentry)
+{
+ return ((struct ecryptfs_dentry_info *)dentry->d_fsdata)->lower_path.mnt;
+}
+
+static inline struct path *
+ecryptfs_dentry_to_lower_path(struct dentry *dentry)
+{
+ return &((struct ecryptfs_dentry_info *)dentry->d_fsdata)->lower_path;
+}
+
+#define ecryptfs_printk(type, fmt, arg...) \
+ __ecryptfs_printk(type "%s: " fmt, __func__, ## arg);
+__printf(1, 2)
+void __ecryptfs_printk(const char *fmt, ...);
+
+extern const struct file_operations ecryptfs_main_fops;
+extern const struct file_operations ecryptfs_dir_fops;
+extern const struct inode_operations ecryptfs_main_iops;
+extern const struct inode_operations ecryptfs_dir_iops;
+extern const struct inode_operations ecryptfs_symlink_iops;
+extern const struct super_operations ecryptfs_sops;
+extern const struct dentry_operations ecryptfs_dops;
+extern const struct address_space_operations ecryptfs_aops;
+extern int ecryptfs_verbosity;
+extern unsigned int ecryptfs_message_buf_len;
+extern signed long ecryptfs_message_wait_timeout;
+extern unsigned int ecryptfs_number_of_users;
+
+extern struct kmem_cache *ecryptfs_auth_tok_list_item_cache;
+extern struct kmem_cache *ecryptfs_file_info_cache;
+extern struct kmem_cache *ecryptfs_dentry_info_cache;
+extern struct kmem_cache *ecryptfs_inode_info_cache;
+extern struct kmem_cache *ecryptfs_sb_info_cache;
+extern struct kmem_cache *ecryptfs_header_cache;
+extern struct kmem_cache *ecryptfs_xattr_cache;
+extern struct kmem_cache *ecryptfs_key_record_cache;
+extern struct kmem_cache *ecryptfs_key_sig_cache;
+extern struct kmem_cache *ecryptfs_global_auth_tok_cache;
+extern struct kmem_cache *ecryptfs_key_tfm_cache;
+
+struct inode *ecryptfs_get_inode(struct inode *lower_inode,
+ struct super_block *sb);
+void ecryptfs_i_size_init(const char *page_virt, struct inode *inode);
+int ecryptfs_initialize_file(struct dentry *ecryptfs_dentry,
+ struct inode *ecryptfs_inode);
+int ecryptfs_decode_and_decrypt_filename(char **decrypted_name,
+ size_t *decrypted_name_size,
+ struct super_block *sb,
+ const char *name, size_t name_size);
+int ecryptfs_fill_zeros(struct file *file, loff_t new_length);
+int ecryptfs_encrypt_and_encode_filename(
+ char **encoded_name,
+ size_t *encoded_name_size,
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
+ const char *name, size_t name_size);
+struct dentry *ecryptfs_lower_dentry(struct dentry *this_dentry);
+void ecryptfs_dump_hex(char *data, int bytes);
+int virt_to_scatterlist(const void *addr, int size, struct scatterlist *sg,
+ int sg_size);
+int ecryptfs_compute_root_iv(struct ecryptfs_crypt_stat *crypt_stat);
+void ecryptfs_rotate_iv(unsigned char *iv);
+int ecryptfs_init_crypt_stat(struct ecryptfs_crypt_stat *crypt_stat);
+void ecryptfs_destroy_crypt_stat(struct ecryptfs_crypt_stat *crypt_stat);
+void ecryptfs_destroy_mount_crypt_stat(
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat);
+int ecryptfs_init_crypt_ctx(struct ecryptfs_crypt_stat *crypt_stat);
+int ecryptfs_write_inode_size_to_metadata(struct inode *ecryptfs_inode);
+int ecryptfs_encrypt_page(struct page *page);
+int ecryptfs_decrypt_page(struct page *page);
+int ecryptfs_write_metadata(struct dentry *ecryptfs_dentry,
+ struct inode *ecryptfs_inode);
+int ecryptfs_read_metadata(struct dentry *ecryptfs_dentry);
+int ecryptfs_new_file_context(struct inode *ecryptfs_inode);
+void ecryptfs_write_crypt_stat_flags(char *page_virt,
+ struct ecryptfs_crypt_stat *crypt_stat,
+ size_t *written);
+int ecryptfs_read_and_validate_header_region(struct inode *inode);
+int ecryptfs_read_and_validate_xattr_region(struct dentry *dentry,
+ struct inode *inode);
+u8 ecryptfs_code_for_cipher_string(char *cipher_name, size_t key_bytes);
+int ecryptfs_cipher_code_to_string(char *str, u8 cipher_code);
+void ecryptfs_set_default_sizes(struct ecryptfs_crypt_stat *crypt_stat);
+int ecryptfs_generate_key_packet_set(char *dest_base,
+ struct ecryptfs_crypt_stat *crypt_stat,
+ struct dentry *ecryptfs_dentry,
+ size_t *len, size_t max);
+int
+ecryptfs_parse_packet_set(struct ecryptfs_crypt_stat *crypt_stat,
+ unsigned char *src, struct dentry *ecryptfs_dentry);
+int ecryptfs_truncate(struct dentry *dentry, loff_t new_length);
+ssize_t
+ecryptfs_getxattr_lower(struct dentry *lower_dentry, struct inode *lower_inode,
+ const char *name, void *value, size_t size);
+int
+ecryptfs_setxattr(struct dentry *dentry, struct inode *inode, const char *name,
+ const void *value, size_t size, int flags);
+int ecryptfs_read_xattr_region(char *page_virt, struct inode *ecryptfs_inode);
+#ifdef CONFIG_ECRYPT_FS_MESSAGING
+int ecryptfs_process_response(struct ecryptfs_daemon *daemon,
+ struct ecryptfs_message *msg, u32 seq);
+int ecryptfs_send_message(char *data, int data_len,
+ struct ecryptfs_msg_ctx **msg_ctx);
+int ecryptfs_wait_for_response(struct ecryptfs_msg_ctx *msg_ctx,
+ struct ecryptfs_message **emsg);
+int ecryptfs_init_messaging(void);
+void ecryptfs_release_messaging(void);
+#else
+static inline int ecryptfs_init_messaging(void)
+{
+ return 0;
+}
+static inline void ecryptfs_release_messaging(void)
+{ }
+static inline int ecryptfs_send_message(char *data, int data_len,
+ struct ecryptfs_msg_ctx **msg_ctx)
+{
+ return -ENOTCONN;
+}
+static inline int ecryptfs_wait_for_response(struct ecryptfs_msg_ctx *msg_ctx,
+ struct ecryptfs_message **emsg)
+{
+ return -ENOMSG;
+}
+#endif
+
+void
+ecryptfs_write_header_metadata(char *virt,
+ struct ecryptfs_crypt_stat *crypt_stat,
+ size_t *written);
+int ecryptfs_add_keysig(struct ecryptfs_crypt_stat *crypt_stat, char *sig);
+int
+ecryptfs_add_global_auth_tok(struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
+ char *sig, u32 global_auth_tok_flags);
+int ecryptfs_get_global_auth_tok_for_sig(
+ struct ecryptfs_global_auth_tok **global_auth_tok,
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat, char *sig);
+int
+ecryptfs_add_new_key_tfm(struct ecryptfs_key_tfm **key_tfm, char *cipher_name,
+ size_t key_size);
+int ecryptfs_init_crypto(void);
+int ecryptfs_destroy_crypto(void);
+int ecryptfs_tfm_exists(char *cipher_name, struct ecryptfs_key_tfm **key_tfm);
+int ecryptfs_get_tfm_and_mutex_for_cipher_name(struct crypto_skcipher **tfm,
+ struct mutex **tfm_mutex,
+ char *cipher_name);
+int ecryptfs_keyring_auth_tok_for_sig(struct key **auth_tok_key,
+ struct ecryptfs_auth_tok **auth_tok,
+ char *sig);
+int ecryptfs_write_lower(struct inode *ecryptfs_inode, char *data,
+ loff_t offset, size_t size);
+int ecryptfs_write_lower_page_segment(struct inode *ecryptfs_inode,
+ struct page *page_for_lower,
+ size_t offset_in_page, size_t size);
+int ecryptfs_write(struct inode *inode, char *data, loff_t offset, size_t size);
+int ecryptfs_read_lower(char *data, loff_t offset, size_t size,
+ struct inode *ecryptfs_inode);
+int ecryptfs_read_lower_page_segment(struct page *page_for_ecryptfs,
+ pgoff_t page_index,
+ size_t offset_in_page, size_t size,
+ struct inode *ecryptfs_inode);
+struct page *ecryptfs_get_locked_page(struct inode *inode, loff_t index);
+int ecryptfs_parse_packet_length(unsigned char *data, size_t *size,
+ size_t *length_size);
+int ecryptfs_write_packet_length(char *dest, size_t size,
+ size_t *packet_size_length);
+#ifdef CONFIG_ECRYPT_FS_MESSAGING
+int ecryptfs_init_ecryptfs_miscdev(void);
+void ecryptfs_destroy_ecryptfs_miscdev(void);
+int ecryptfs_send_miscdev(char *data, size_t data_size,
+ struct ecryptfs_msg_ctx *msg_ctx, u8 msg_type,
+ u16 msg_flags, struct ecryptfs_daemon *daemon);
+void ecryptfs_msg_ctx_alloc_to_free(struct ecryptfs_msg_ctx *msg_ctx);
+int
+ecryptfs_spawn_daemon(struct ecryptfs_daemon **daemon, struct file *file);
+int ecryptfs_exorcise_daemon(struct ecryptfs_daemon *daemon);
+int ecryptfs_find_daemon_by_euid(struct ecryptfs_daemon **daemon);
+#endif
+int ecryptfs_init_kthread(void);
+void ecryptfs_destroy_kthread(void);
+int ecryptfs_privileged_open(struct file **lower_file,
+ struct dentry *lower_dentry,
+ struct vfsmount *lower_mnt,
+ const struct cred *cred);
+int ecryptfs_get_lower_file(struct dentry *dentry, struct inode *inode);
+void ecryptfs_put_lower_file(struct inode *inode);
+int
+ecryptfs_write_tag_70_packet(char *dest, size_t *remaining_bytes,
+ size_t *packet_size,
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
+ char *filename, size_t filename_size);
+int
+ecryptfs_parse_tag_70_packet(char **filename, size_t *filename_size,
+ size_t *packet_size,
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
+ char *data, size_t max_packet_size);
+int ecryptfs_set_f_namelen(long *namelen, long lower_namelen,
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat);
+int ecryptfs_derive_iv(char *iv, struct ecryptfs_crypt_stat *crypt_stat,
+ loff_t offset);
+
+extern const struct xattr_handler *ecryptfs_xattr_handlers[];
+
+#endif /* #ifndef ECRYPTFS_KERNEL_H */
diff --git a/fs/ecryptfs/file.c b/fs/ecryptfs/file.c
new file mode 100644
index 0000000..b76a985
--- /dev/null
+++ b/fs/ecryptfs/file.c
@@ -0,0 +1,437 @@
+/**
+ * eCryptfs: Linux filesystem encryption layer
+ *
+ * Copyright (C) 1997-2004 Erez Zadok
+ * Copyright (C) 2001-2004 Stony Brook University
+ * Copyright (C) 2004-2007 International Business Machines Corp.
+ * Author(s): Michael A. Halcrow <mhalcrow@us.ibm.com>
+ * Michael C. Thompson <mcthomps@us.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ */
+
+#include <linux/file.h>
+#include <linux/poll.h>
+#include <linux/slab.h>
+#include <linux/mount.h>
+#include <linux/pagemap.h>
+#include <linux/security.h>
+#include <linux/compat.h>
+#include <linux/fs_stack.h>
+#include "ecryptfs_kernel.h"
+
+/**
+ * ecryptfs_read_update_atime
+ *
+ * generic_file_read updates the atime of upper layer inode. But, it
+ * doesn't give us a chance to update the atime of the lower layer
+ * inode. This function is a wrapper to generic_file_read. It
+ * updates the atime of the lower level inode if generic_file_read
+ * returns without any errors. This is to be used only for file reads.
+ * The function to be used for directory reads is ecryptfs_read.
+ */
+static ssize_t ecryptfs_read_update_atime(struct kiocb *iocb,
+ struct iov_iter *to)
+{
+ ssize_t rc;
+ struct path *path;
+ struct file *file = iocb->ki_filp;
+
+ rc = generic_file_read_iter(iocb, to);
+ if (rc >= 0) {
+ path = ecryptfs_dentry_to_lower_path(file->f_path.dentry);
+ touch_atime(path);
+ }
+ return rc;
+}
+
+struct ecryptfs_getdents_callback {
+ struct dir_context ctx;
+ struct dir_context *caller;
+ struct super_block *sb;
+ int filldir_called;
+ int entries_written;
+};
+
+/* Inspired by generic filldir in fs/readdir.c */
+static int
+ecryptfs_filldir(struct dir_context *ctx, const char *lower_name,
+ int lower_namelen, loff_t offset, u64 ino, unsigned int d_type)
+{
+ struct ecryptfs_getdents_callback *buf =
+ container_of(ctx, struct ecryptfs_getdents_callback, ctx);
+ size_t name_size;
+ char *name;
+ int rc;
+
+ buf->filldir_called++;
+ rc = ecryptfs_decode_and_decrypt_filename(&name, &name_size,
+ buf->sb, lower_name,
+ lower_namelen);
+ if (rc) {
+ if (rc != -EINVAL) {
+ ecryptfs_printk(KERN_DEBUG,
+ "%s: Error attempting to decode and decrypt filename [%s]; rc = [%d]\n",
+ __func__, lower_name, rc);
+ return rc;
+ }
+
+ /* Mask -EINVAL errors as these are most likely due a plaintext
+ * filename present in the lower filesystem despite filename
+ * encryption being enabled. One unavoidable example would be
+ * the "lost+found" dentry in the root directory of an Ext4
+ * filesystem.
+ */
+ return 0;
+ }
+
+ buf->caller->pos = buf->ctx.pos;
+ rc = !dir_emit(buf->caller, name, name_size, ino, d_type);
+ kfree(name);
+ if (!rc)
+ buf->entries_written++;
+
+ return rc;
+}
+
+/**
+ * ecryptfs_readdir
+ * @file: The eCryptfs directory file
+ * @ctx: The actor to feed the entries to
+ */
+static int ecryptfs_readdir(struct file *file, struct dir_context *ctx)
+{
+ int rc;
+ struct file *lower_file;
+ struct inode *inode = file_inode(file);
+ struct ecryptfs_getdents_callback buf = {
+ .ctx.actor = ecryptfs_filldir,
+ .caller = ctx,
+ .sb = inode->i_sb,
+ };
+ lower_file = ecryptfs_file_to_lower(file);
+ rc = iterate_dir(lower_file, &buf.ctx);
+ ctx->pos = buf.ctx.pos;
+ if (rc < 0)
+ goto out;
+ if (buf.filldir_called && !buf.entries_written)
+ goto out;
+ if (rc >= 0)
+ fsstack_copy_attr_atime(inode,
+ file_inode(lower_file));
+out:
+ return rc;
+}
+
+struct kmem_cache *ecryptfs_file_info_cache;
+
+static int read_or_initialize_metadata(struct dentry *dentry)
+{
+ struct inode *inode = d_inode(dentry);
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
+ struct ecryptfs_crypt_stat *crypt_stat;
+ int rc;
+
+ crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat;
+ mount_crypt_stat = &ecryptfs_superblock_to_private(
+ inode->i_sb)->mount_crypt_stat;
+ mutex_lock(&crypt_stat->cs_mutex);
+
+ if (crypt_stat->flags & ECRYPTFS_POLICY_APPLIED &&
+ crypt_stat->flags & ECRYPTFS_KEY_VALID) {
+ rc = 0;
+ goto out;
+ }
+
+ rc = ecryptfs_read_metadata(dentry);
+ if (!rc)
+ goto out;
+
+ if (mount_crypt_stat->flags & ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED) {
+ crypt_stat->flags &= ~(ECRYPTFS_I_SIZE_INITIALIZED
+ | ECRYPTFS_ENCRYPTED);
+ rc = 0;
+ goto out;
+ }
+
+ if (!(mount_crypt_stat->flags & ECRYPTFS_XATTR_METADATA_ENABLED) &&
+ !i_size_read(ecryptfs_inode_to_lower(inode))) {
+ rc = ecryptfs_initialize_file(dentry, inode);
+ if (!rc)
+ goto out;
+ }
+
+ rc = -EIO;
+out:
+ mutex_unlock(&crypt_stat->cs_mutex);
+ return rc;
+}
+
+static int ecryptfs_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ struct file *lower_file = ecryptfs_file_to_lower(file);
+ /*
+ * Don't allow mmap on top of file systems that don't support it
+ * natively. If FILESYSTEM_MAX_STACK_DEPTH > 2 or ecryptfs
+ * allows recursive mounting, this will need to be extended.
+ */
+ if (!lower_file->f_op->mmap)
+ return -ENODEV;
+ return generic_file_mmap(file, vma);
+}
+
+/**
+ * ecryptfs_open
+ * @inode: inode specifying file to open
+ * @file: Structure to return filled in
+ *
+ * Opens the file specified by inode.
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+static int ecryptfs_open(struct inode *inode, struct file *file)
+{
+ int rc = 0;
+ struct ecryptfs_crypt_stat *crypt_stat = NULL;
+ struct dentry *ecryptfs_dentry = file->f_path.dentry;
+ /* Private value of ecryptfs_dentry allocated in
+ * ecryptfs_lookup() */
+ struct ecryptfs_file_info *file_info;
+
+ /* Released in ecryptfs_release or end of function if failure */
+ file_info = kmem_cache_zalloc(ecryptfs_file_info_cache, GFP_KERNEL);
+ ecryptfs_set_file_private(file, file_info);
+ if (!file_info) {
+ ecryptfs_printk(KERN_ERR,
+ "Error attempting to allocate memory\n");
+ rc = -ENOMEM;
+ goto out;
+ }
+ crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat;
+ mutex_lock(&crypt_stat->cs_mutex);
+ if (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED)) {
+ ecryptfs_printk(KERN_DEBUG, "Setting flags for stat...\n");
+ /* Policy code enabled in future release */
+ crypt_stat->flags |= (ECRYPTFS_POLICY_APPLIED
+ | ECRYPTFS_ENCRYPTED);
+ }
+ mutex_unlock(&crypt_stat->cs_mutex);
+ rc = ecryptfs_get_lower_file(ecryptfs_dentry, inode);
+ if (rc) {
+ printk(KERN_ERR "%s: Error attempting to initialize "
+ "the lower file for the dentry with name "
+ "[%pd]; rc = [%d]\n", __func__,
+ ecryptfs_dentry, rc);
+ goto out_free;
+ }
+ if ((ecryptfs_inode_to_private(inode)->lower_file->f_flags & O_ACCMODE)
+ == O_RDONLY && (file->f_flags & O_ACCMODE) != O_RDONLY) {
+ rc = -EPERM;
+ printk(KERN_WARNING "%s: Lower file is RO; eCryptfs "
+ "file must hence be opened RO\n", __func__);
+ goto out_put;
+ }
+ ecryptfs_set_file_lower(
+ file, ecryptfs_inode_to_private(inode)->lower_file);
+ rc = read_or_initialize_metadata(ecryptfs_dentry);
+ if (rc)
+ goto out_put;
+ ecryptfs_printk(KERN_DEBUG, "inode w/ addr = [0x%p], i_ino = "
+ "[0x%.16lx] size: [0x%.16llx]\n", inode, inode->i_ino,
+ (unsigned long long)i_size_read(inode));
+ goto out;
+out_put:
+ ecryptfs_put_lower_file(inode);
+out_free:
+ kmem_cache_free(ecryptfs_file_info_cache,
+ ecryptfs_file_to_private(file));
+out:
+ return rc;
+}
+
+/**
+ * ecryptfs_dir_open
+ * @inode: inode specifying file to open
+ * @file: Structure to return filled in
+ *
+ * Opens the file specified by inode.
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+static int ecryptfs_dir_open(struct inode *inode, struct file *file)
+{
+ struct dentry *ecryptfs_dentry = file->f_path.dentry;
+ /* Private value of ecryptfs_dentry allocated in
+ * ecryptfs_lookup() */
+ struct ecryptfs_file_info *file_info;
+ struct file *lower_file;
+
+ /* Released in ecryptfs_release or end of function if failure */
+ file_info = kmem_cache_zalloc(ecryptfs_file_info_cache, GFP_KERNEL);
+ ecryptfs_set_file_private(file, file_info);
+ if (unlikely(!file_info)) {
+ ecryptfs_printk(KERN_ERR,
+ "Error attempting to allocate memory\n");
+ return -ENOMEM;
+ }
+ lower_file = dentry_open(ecryptfs_dentry_to_lower_path(ecryptfs_dentry),
+ file->f_flags, current_cred());
+ if (IS_ERR(lower_file)) {
+ printk(KERN_ERR "%s: Error attempting to initialize "
+ "the lower file for the dentry with name "
+ "[%pd]; rc = [%ld]\n", __func__,
+ ecryptfs_dentry, PTR_ERR(lower_file));
+ kmem_cache_free(ecryptfs_file_info_cache, file_info);
+ return PTR_ERR(lower_file);
+ }
+ ecryptfs_set_file_lower(file, lower_file);
+ return 0;
+}
+
+static int ecryptfs_flush(struct file *file, fl_owner_t td)
+{
+ struct file *lower_file = ecryptfs_file_to_lower(file);
+
+ if (lower_file->f_op->flush) {
+ filemap_write_and_wait(file->f_mapping);
+ return lower_file->f_op->flush(lower_file, td);
+ }
+
+ return 0;
+}
+
+static int ecryptfs_release(struct inode *inode, struct file *file)
+{
+ ecryptfs_put_lower_file(inode);
+ kmem_cache_free(ecryptfs_file_info_cache,
+ ecryptfs_file_to_private(file));
+ return 0;
+}
+
+static int ecryptfs_dir_release(struct inode *inode, struct file *file)
+{
+ fput(ecryptfs_file_to_lower(file));
+ kmem_cache_free(ecryptfs_file_info_cache,
+ ecryptfs_file_to_private(file));
+ return 0;
+}
+
+static loff_t ecryptfs_dir_llseek(struct file *file, loff_t offset, int whence)
+{
+ return vfs_llseek(ecryptfs_file_to_lower(file), offset, whence);
+}
+
+static int
+ecryptfs_fsync(struct file *file, loff_t start, loff_t end, int datasync)
+{
+ int rc;
+
+ rc = file_write_and_wait(file);
+ if (rc)
+ return rc;
+
+ return vfs_fsync(ecryptfs_file_to_lower(file), datasync);
+}
+
+static int ecryptfs_fasync(int fd, struct file *file, int flag)
+{
+ int rc = 0;
+ struct file *lower_file = NULL;
+
+ lower_file = ecryptfs_file_to_lower(file);
+ if (lower_file->f_op->fasync)
+ rc = lower_file->f_op->fasync(fd, lower_file, flag);
+ return rc;
+}
+
+static long
+ecryptfs_unlocked_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+ struct file *lower_file = ecryptfs_file_to_lower(file);
+ long rc = -ENOTTY;
+
+ if (!lower_file->f_op->unlocked_ioctl)
+ return rc;
+
+ switch (cmd) {
+ case FITRIM:
+ case FS_IOC_GETFLAGS:
+ case FS_IOC_SETFLAGS:
+ case FS_IOC_GETVERSION:
+ case FS_IOC_SETVERSION:
+ rc = lower_file->f_op->unlocked_ioctl(lower_file, cmd, arg);
+ fsstack_copy_attr_all(file_inode(file), file_inode(lower_file));
+
+ return rc;
+ default:
+ return rc;
+ }
+}
+
+#ifdef CONFIG_COMPAT
+static long
+ecryptfs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+ struct file *lower_file = ecryptfs_file_to_lower(file);
+ long rc = -ENOIOCTLCMD;
+
+ if (!lower_file->f_op->compat_ioctl)
+ return rc;
+
+ switch (cmd) {
+ case FS_IOC32_GETFLAGS:
+ case FS_IOC32_SETFLAGS:
+ case FS_IOC32_GETVERSION:
+ case FS_IOC32_SETVERSION:
+ rc = lower_file->f_op->compat_ioctl(lower_file, cmd, arg);
+ fsstack_copy_attr_all(file_inode(file), file_inode(lower_file));
+
+ return rc;
+ default:
+ return rc;
+ }
+}
+#endif
+
+const struct file_operations ecryptfs_dir_fops = {
+ .iterate_shared = ecryptfs_readdir,
+ .read = generic_read_dir,
+ .unlocked_ioctl = ecryptfs_unlocked_ioctl,
+#ifdef CONFIG_COMPAT
+ .compat_ioctl = ecryptfs_compat_ioctl,
+#endif
+ .open = ecryptfs_dir_open,
+ .release = ecryptfs_dir_release,
+ .fsync = ecryptfs_fsync,
+ .llseek = ecryptfs_dir_llseek,
+};
+
+const struct file_operations ecryptfs_main_fops = {
+ .llseek = generic_file_llseek,
+ .read_iter = ecryptfs_read_update_atime,
+ .write_iter = generic_file_write_iter,
+ .unlocked_ioctl = ecryptfs_unlocked_ioctl,
+#ifdef CONFIG_COMPAT
+ .compat_ioctl = ecryptfs_compat_ioctl,
+#endif
+ .mmap = ecryptfs_mmap,
+ .open = ecryptfs_open,
+ .flush = ecryptfs_flush,
+ .release = ecryptfs_release,
+ .fsync = ecryptfs_fsync,
+ .fasync = ecryptfs_fasync,
+ .splice_read = generic_file_splice_read,
+};
diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c
new file mode 100644
index 0000000..49121e5
--- /dev/null
+++ b/fs/ecryptfs/inode.c
@@ -0,0 +1,1142 @@
+/**
+ * eCryptfs: Linux filesystem encryption layer
+ *
+ * Copyright (C) 1997-2004 Erez Zadok
+ * Copyright (C) 2001-2004 Stony Brook University
+ * Copyright (C) 2004-2007 International Business Machines Corp.
+ * Author(s): Michael A. Halcrow <mahalcro@us.ibm.com>
+ * Michael C. Thompsion <mcthomps@us.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ */
+
+#include <linux/file.h>
+#include <linux/vmalloc.h>
+#include <linux/pagemap.h>
+#include <linux/dcache.h>
+#include <linux/namei.h>
+#include <linux/mount.h>
+#include <linux/fs_stack.h>
+#include <linux/slab.h>
+#include <linux/xattr.h>
+#include <asm/unaligned.h>
+#include "ecryptfs_kernel.h"
+
+static struct dentry *lock_parent(struct dentry *dentry)
+{
+ struct dentry *dir;
+
+ dir = dget_parent(dentry);
+ inode_lock_nested(d_inode(dir), I_MUTEX_PARENT);
+ return dir;
+}
+
+static void unlock_dir(struct dentry *dir)
+{
+ inode_unlock(d_inode(dir));
+ dput(dir);
+}
+
+static int ecryptfs_inode_test(struct inode *inode, void *lower_inode)
+{
+ return ecryptfs_inode_to_lower(inode) == lower_inode;
+}
+
+static int ecryptfs_inode_set(struct inode *inode, void *opaque)
+{
+ struct inode *lower_inode = opaque;
+
+ ecryptfs_set_inode_lower(inode, lower_inode);
+ fsstack_copy_attr_all(inode, lower_inode);
+ /* i_size will be overwritten for encrypted regular files */
+ fsstack_copy_inode_size(inode, lower_inode);
+ inode->i_ino = lower_inode->i_ino;
+ inode->i_mapping->a_ops = &ecryptfs_aops;
+
+ if (S_ISLNK(inode->i_mode))
+ inode->i_op = &ecryptfs_symlink_iops;
+ else if (S_ISDIR(inode->i_mode))
+ inode->i_op = &ecryptfs_dir_iops;
+ else
+ inode->i_op = &ecryptfs_main_iops;
+
+ if (S_ISDIR(inode->i_mode))
+ inode->i_fop = &ecryptfs_dir_fops;
+ else if (special_file(inode->i_mode))
+ init_special_inode(inode, inode->i_mode, inode->i_rdev);
+ else
+ inode->i_fop = &ecryptfs_main_fops;
+
+ return 0;
+}
+
+static struct inode *__ecryptfs_get_inode(struct inode *lower_inode,
+ struct super_block *sb)
+{
+ struct inode *inode;
+
+ if (lower_inode->i_sb != ecryptfs_superblock_to_lower(sb))
+ return ERR_PTR(-EXDEV);
+ if (!igrab(lower_inode))
+ return ERR_PTR(-ESTALE);
+ inode = iget5_locked(sb, (unsigned long)lower_inode,
+ ecryptfs_inode_test, ecryptfs_inode_set,
+ lower_inode);
+ if (!inode) {
+ iput(lower_inode);
+ return ERR_PTR(-EACCES);
+ }
+ if (!(inode->i_state & I_NEW))
+ iput(lower_inode);
+
+ return inode;
+}
+
+struct inode *ecryptfs_get_inode(struct inode *lower_inode,
+ struct super_block *sb)
+{
+ struct inode *inode = __ecryptfs_get_inode(lower_inode, sb);
+
+ if (!IS_ERR(inode) && (inode->i_state & I_NEW))
+ unlock_new_inode(inode);
+
+ return inode;
+}
+
+/**
+ * ecryptfs_interpose
+ * @lower_dentry: Existing dentry in the lower filesystem
+ * @dentry: ecryptfs' dentry
+ * @sb: ecryptfs's super_block
+ *
+ * Interposes upper and lower dentries.
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+static int ecryptfs_interpose(struct dentry *lower_dentry,
+ struct dentry *dentry, struct super_block *sb)
+{
+ struct inode *inode = ecryptfs_get_inode(d_inode(lower_dentry), sb);
+
+ if (IS_ERR(inode))
+ return PTR_ERR(inode);
+ d_instantiate(dentry, inode);
+
+ return 0;
+}
+
+static int ecryptfs_do_unlink(struct inode *dir, struct dentry *dentry,
+ struct inode *inode)
+{
+ struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
+ struct inode *lower_dir_inode = ecryptfs_inode_to_lower(dir);
+ struct dentry *lower_dir_dentry;
+ int rc;
+
+ dget(lower_dentry);
+ lower_dir_dentry = lock_parent(lower_dentry);
+ rc = vfs_unlink(lower_dir_inode, lower_dentry, NULL);
+ if (rc) {
+ printk(KERN_ERR "Error in vfs_unlink; rc = [%d]\n", rc);
+ goto out_unlock;
+ }
+ fsstack_copy_attr_times(dir, lower_dir_inode);
+ set_nlink(inode, ecryptfs_inode_to_lower(inode)->i_nlink);
+ inode->i_ctime = dir->i_ctime;
+ d_drop(dentry);
+out_unlock:
+ unlock_dir(lower_dir_dentry);
+ dput(lower_dentry);
+ return rc;
+}
+
+/**
+ * ecryptfs_do_create
+ * @directory_inode: inode of the new file's dentry's parent in ecryptfs
+ * @ecryptfs_dentry: New file's dentry in ecryptfs
+ * @mode: The mode of the new file
+ *
+ * Creates the underlying file and the eCryptfs inode which will link to
+ * it. It will also update the eCryptfs directory inode to mimic the
+ * stat of the lower directory inode.
+ *
+ * Returns the new eCryptfs inode on success; an ERR_PTR on error condition
+ */
+static struct inode *
+ecryptfs_do_create(struct inode *directory_inode,
+ struct dentry *ecryptfs_dentry, umode_t mode)
+{
+ int rc;
+ struct dentry *lower_dentry;
+ struct dentry *lower_dir_dentry;
+ struct inode *inode;
+
+ lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry);
+ lower_dir_dentry = lock_parent(lower_dentry);
+ rc = vfs_create(d_inode(lower_dir_dentry), lower_dentry, mode, true);
+ if (rc) {
+ printk(KERN_ERR "%s: Failure to create dentry in lower fs; "
+ "rc = [%d]\n", __func__, rc);
+ inode = ERR_PTR(rc);
+ goto out_lock;
+ }
+ inode = __ecryptfs_get_inode(d_inode(lower_dentry),
+ directory_inode->i_sb);
+ if (IS_ERR(inode)) {
+ vfs_unlink(d_inode(lower_dir_dentry), lower_dentry, NULL);
+ goto out_lock;
+ }
+ fsstack_copy_attr_times(directory_inode, d_inode(lower_dir_dentry));
+ fsstack_copy_inode_size(directory_inode, d_inode(lower_dir_dentry));
+out_lock:
+ unlock_dir(lower_dir_dentry);
+ return inode;
+}
+
+/**
+ * ecryptfs_initialize_file
+ *
+ * Cause the file to be changed from a basic empty file to an ecryptfs
+ * file with a header and first data page.
+ *
+ * Returns zero on success
+ */
+int ecryptfs_initialize_file(struct dentry *ecryptfs_dentry,
+ struct inode *ecryptfs_inode)
+{
+ struct ecryptfs_crypt_stat *crypt_stat =
+ &ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat;
+ int rc = 0;
+
+ if (S_ISDIR(ecryptfs_inode->i_mode)) {
+ ecryptfs_printk(KERN_DEBUG, "This is a directory\n");
+ crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED);
+ goto out;
+ }
+ ecryptfs_printk(KERN_DEBUG, "Initializing crypto context\n");
+ rc = ecryptfs_new_file_context(ecryptfs_inode);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error creating new file "
+ "context; rc = [%d]\n", rc);
+ goto out;
+ }
+ rc = ecryptfs_get_lower_file(ecryptfs_dentry, ecryptfs_inode);
+ if (rc) {
+ printk(KERN_ERR "%s: Error attempting to initialize "
+ "the lower file for the dentry with name "
+ "[%pd]; rc = [%d]\n", __func__,
+ ecryptfs_dentry, rc);
+ goto out;
+ }
+ rc = ecryptfs_write_metadata(ecryptfs_dentry, ecryptfs_inode);
+ if (rc)
+ printk(KERN_ERR "Error writing headers; rc = [%d]\n", rc);
+ ecryptfs_put_lower_file(ecryptfs_inode);
+out:
+ return rc;
+}
+
+/**
+ * ecryptfs_create
+ * @dir: The inode of the directory in which to create the file.
+ * @dentry: The eCryptfs dentry
+ * @mode: The mode of the new file.
+ *
+ * Creates a new file.
+ *
+ * Returns zero on success; non-zero on error condition
+ */
+static int
+ecryptfs_create(struct inode *directory_inode, struct dentry *ecryptfs_dentry,
+ umode_t mode, bool excl)
+{
+ struct inode *ecryptfs_inode;
+ int rc;
+
+ ecryptfs_inode = ecryptfs_do_create(directory_inode, ecryptfs_dentry,
+ mode);
+ if (IS_ERR(ecryptfs_inode)) {
+ ecryptfs_printk(KERN_WARNING, "Failed to create file in"
+ "lower filesystem\n");
+ rc = PTR_ERR(ecryptfs_inode);
+ goto out;
+ }
+ /* At this point, a file exists on "disk"; we need to make sure
+ * that this on disk file is prepared to be an ecryptfs file */
+ rc = ecryptfs_initialize_file(ecryptfs_dentry, ecryptfs_inode);
+ if (rc) {
+ ecryptfs_do_unlink(directory_inode, ecryptfs_dentry,
+ ecryptfs_inode);
+ iget_failed(ecryptfs_inode);
+ goto out;
+ }
+ d_instantiate_new(ecryptfs_dentry, ecryptfs_inode);
+out:
+ return rc;
+}
+
+static int ecryptfs_i_size_read(struct dentry *dentry, struct inode *inode)
+{
+ struct ecryptfs_crypt_stat *crypt_stat;
+ int rc;
+
+ rc = ecryptfs_get_lower_file(dentry, inode);
+ if (rc) {
+ printk(KERN_ERR "%s: Error attempting to initialize "
+ "the lower file for the dentry with name "
+ "[%pd]; rc = [%d]\n", __func__,
+ dentry, rc);
+ return rc;
+ }
+
+ crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat;
+ /* TODO: lock for crypt_stat comparison */
+ if (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED))
+ ecryptfs_set_default_sizes(crypt_stat);
+
+ rc = ecryptfs_read_and_validate_header_region(inode);
+ ecryptfs_put_lower_file(inode);
+ if (rc) {
+ rc = ecryptfs_read_and_validate_xattr_region(dentry, inode);
+ if (!rc)
+ crypt_stat->flags |= ECRYPTFS_METADATA_IN_XATTR;
+ }
+
+ /* Must return 0 to allow non-eCryptfs files to be looked up, too */
+ return 0;
+}
+
+/**
+ * ecryptfs_lookup_interpose - Dentry interposition for a lookup
+ */
+static struct dentry *ecryptfs_lookup_interpose(struct dentry *dentry,
+ struct dentry *lower_dentry)
+{
+ struct inode *inode, *lower_inode = d_inode(lower_dentry);
+ struct ecryptfs_dentry_info *dentry_info;
+ struct vfsmount *lower_mnt;
+ int rc = 0;
+
+ dentry_info = kmem_cache_alloc(ecryptfs_dentry_info_cache, GFP_KERNEL);
+ if (!dentry_info) {
+ dput(lower_dentry);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ lower_mnt = mntget(ecryptfs_dentry_to_lower_mnt(dentry->d_parent));
+ fsstack_copy_attr_atime(d_inode(dentry->d_parent),
+ d_inode(lower_dentry->d_parent));
+ BUG_ON(!d_count(lower_dentry));
+
+ ecryptfs_set_dentry_private(dentry, dentry_info);
+ dentry_info->lower_path.mnt = lower_mnt;
+ dentry_info->lower_path.dentry = lower_dentry;
+
+ if (d_really_is_negative(lower_dentry)) {
+ /* We want to add because we couldn't find in lower */
+ d_add(dentry, NULL);
+ return NULL;
+ }
+ inode = __ecryptfs_get_inode(lower_inode, dentry->d_sb);
+ if (IS_ERR(inode)) {
+ printk(KERN_ERR "%s: Error interposing; rc = [%ld]\n",
+ __func__, PTR_ERR(inode));
+ return ERR_CAST(inode);
+ }
+ if (S_ISREG(inode->i_mode)) {
+ rc = ecryptfs_i_size_read(dentry, inode);
+ if (rc) {
+ make_bad_inode(inode);
+ return ERR_PTR(rc);
+ }
+ }
+
+ if (inode->i_state & I_NEW)
+ unlock_new_inode(inode);
+ return d_splice_alias(inode, dentry);
+}
+
+/**
+ * ecryptfs_lookup
+ * @ecryptfs_dir_inode: The eCryptfs directory inode
+ * @ecryptfs_dentry: The eCryptfs dentry that we are looking up
+ * @flags: lookup flags
+ *
+ * Find a file on disk. If the file does not exist, then we'll add it to the
+ * dentry cache and continue on to read it from the disk.
+ */
+static struct dentry *ecryptfs_lookup(struct inode *ecryptfs_dir_inode,
+ struct dentry *ecryptfs_dentry,
+ unsigned int flags)
+{
+ char *encrypted_and_encoded_name = NULL;
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
+ struct dentry *lower_dir_dentry, *lower_dentry;
+ const char *name = ecryptfs_dentry->d_name.name;
+ size_t len = ecryptfs_dentry->d_name.len;
+ struct dentry *res;
+ int rc = 0;
+
+ lower_dir_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry->d_parent);
+
+ mount_crypt_stat = &ecryptfs_superblock_to_private(
+ ecryptfs_dentry->d_sb)->mount_crypt_stat;
+ if (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES) {
+ rc = ecryptfs_encrypt_and_encode_filename(
+ &encrypted_and_encoded_name, &len,
+ mount_crypt_stat, name, len);
+ if (rc) {
+ printk(KERN_ERR "%s: Error attempting to encrypt and encode "
+ "filename; rc = [%d]\n", __func__, rc);
+ return ERR_PTR(rc);
+ }
+ name = encrypted_and_encoded_name;
+ }
+
+ lower_dentry = lookup_one_len_unlocked(name, lower_dir_dentry, len);
+ if (IS_ERR(lower_dentry)) {
+ ecryptfs_printk(KERN_DEBUG, "%s: lookup_one_len() returned "
+ "[%ld] on lower_dentry = [%s]\n", __func__,
+ PTR_ERR(lower_dentry),
+ name);
+ res = ERR_CAST(lower_dentry);
+ } else {
+ res = ecryptfs_lookup_interpose(ecryptfs_dentry, lower_dentry);
+ }
+ kfree(encrypted_and_encoded_name);
+ return res;
+}
+
+static int ecryptfs_link(struct dentry *old_dentry, struct inode *dir,
+ struct dentry *new_dentry)
+{
+ struct dentry *lower_old_dentry;
+ struct dentry *lower_new_dentry;
+ struct dentry *lower_dir_dentry;
+ u64 file_size_save;
+ int rc;
+
+ file_size_save = i_size_read(d_inode(old_dentry));
+ lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry);
+ lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry);
+ dget(lower_old_dentry);
+ dget(lower_new_dentry);
+ lower_dir_dentry = lock_parent(lower_new_dentry);
+ rc = vfs_link(lower_old_dentry, d_inode(lower_dir_dentry),
+ lower_new_dentry, NULL);
+ if (rc || d_really_is_negative(lower_new_dentry))
+ goto out_lock;
+ rc = ecryptfs_interpose(lower_new_dentry, new_dentry, dir->i_sb);
+ if (rc)
+ goto out_lock;
+ fsstack_copy_attr_times(dir, d_inode(lower_dir_dentry));
+ fsstack_copy_inode_size(dir, d_inode(lower_dir_dentry));
+ set_nlink(d_inode(old_dentry),
+ ecryptfs_inode_to_lower(d_inode(old_dentry))->i_nlink);
+ i_size_write(d_inode(new_dentry), file_size_save);
+out_lock:
+ unlock_dir(lower_dir_dentry);
+ dput(lower_new_dentry);
+ dput(lower_old_dentry);
+ return rc;
+}
+
+static int ecryptfs_unlink(struct inode *dir, struct dentry *dentry)
+{
+ return ecryptfs_do_unlink(dir, dentry, d_inode(dentry));
+}
+
+static int ecryptfs_symlink(struct inode *dir, struct dentry *dentry,
+ const char *symname)
+{
+ int rc;
+ struct dentry *lower_dentry;
+ struct dentry *lower_dir_dentry;
+ char *encoded_symname;
+ size_t encoded_symlen;
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat = NULL;
+
+ lower_dentry = ecryptfs_dentry_to_lower(dentry);
+ dget(lower_dentry);
+ lower_dir_dentry = lock_parent(lower_dentry);
+ mount_crypt_stat = &ecryptfs_superblock_to_private(
+ dir->i_sb)->mount_crypt_stat;
+ rc = ecryptfs_encrypt_and_encode_filename(&encoded_symname,
+ &encoded_symlen,
+ mount_crypt_stat, symname,
+ strlen(symname));
+ if (rc)
+ goto out_lock;
+ rc = vfs_symlink(d_inode(lower_dir_dentry), lower_dentry,
+ encoded_symname);
+ kfree(encoded_symname);
+ if (rc || d_really_is_negative(lower_dentry))
+ goto out_lock;
+ rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb);
+ if (rc)
+ goto out_lock;
+ fsstack_copy_attr_times(dir, d_inode(lower_dir_dentry));
+ fsstack_copy_inode_size(dir, d_inode(lower_dir_dentry));
+out_lock:
+ unlock_dir(lower_dir_dentry);
+ dput(lower_dentry);
+ if (d_really_is_negative(dentry))
+ d_drop(dentry);
+ return rc;
+}
+
+static int ecryptfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
+{
+ int rc;
+ struct dentry *lower_dentry;
+ struct dentry *lower_dir_dentry;
+
+ lower_dentry = ecryptfs_dentry_to_lower(dentry);
+ lower_dir_dentry = lock_parent(lower_dentry);
+ rc = vfs_mkdir(d_inode(lower_dir_dentry), lower_dentry, mode);
+ if (rc || d_really_is_negative(lower_dentry))
+ goto out;
+ rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb);
+ if (rc)
+ goto out;
+ fsstack_copy_attr_times(dir, d_inode(lower_dir_dentry));
+ fsstack_copy_inode_size(dir, d_inode(lower_dir_dentry));
+ set_nlink(dir, d_inode(lower_dir_dentry)->i_nlink);
+out:
+ unlock_dir(lower_dir_dentry);
+ if (d_really_is_negative(dentry))
+ d_drop(dentry);
+ return rc;
+}
+
+static int ecryptfs_rmdir(struct inode *dir, struct dentry *dentry)
+{
+ struct dentry *lower_dentry;
+ struct dentry *lower_dir_dentry;
+ int rc;
+
+ lower_dentry = ecryptfs_dentry_to_lower(dentry);
+ dget(dentry);
+ lower_dir_dentry = lock_parent(lower_dentry);
+ dget(lower_dentry);
+ rc = vfs_rmdir(d_inode(lower_dir_dentry), lower_dentry);
+ dput(lower_dentry);
+ if (!rc && d_really_is_positive(dentry))
+ clear_nlink(d_inode(dentry));
+ fsstack_copy_attr_times(dir, d_inode(lower_dir_dentry));
+ set_nlink(dir, d_inode(lower_dir_dentry)->i_nlink);
+ unlock_dir(lower_dir_dentry);
+ if (!rc)
+ d_drop(dentry);
+ dput(dentry);
+ return rc;
+}
+
+static int
+ecryptfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
+{
+ int rc;
+ struct dentry *lower_dentry;
+ struct dentry *lower_dir_dentry;
+
+ lower_dentry = ecryptfs_dentry_to_lower(dentry);
+ lower_dir_dentry = lock_parent(lower_dentry);
+ rc = vfs_mknod(d_inode(lower_dir_dentry), lower_dentry, mode, dev);
+ if (rc || d_really_is_negative(lower_dentry))
+ goto out;
+ rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb);
+ if (rc)
+ goto out;
+ fsstack_copy_attr_times(dir, d_inode(lower_dir_dentry));
+ fsstack_copy_inode_size(dir, d_inode(lower_dir_dentry));
+out:
+ unlock_dir(lower_dir_dentry);
+ if (d_really_is_negative(dentry))
+ d_drop(dentry);
+ return rc;
+}
+
+static int
+ecryptfs_rename(struct inode *old_dir, struct dentry *old_dentry,
+ struct inode *new_dir, struct dentry *new_dentry,
+ unsigned int flags)
+{
+ int rc;
+ struct dentry *lower_old_dentry;
+ struct dentry *lower_new_dentry;
+ struct dentry *lower_old_dir_dentry;
+ struct dentry *lower_new_dir_dentry;
+ struct dentry *trap = NULL;
+ struct inode *target_inode;
+
+ if (flags)
+ return -EINVAL;
+
+ lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry);
+ lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry);
+ dget(lower_old_dentry);
+ dget(lower_new_dentry);
+ lower_old_dir_dentry = dget_parent(lower_old_dentry);
+ lower_new_dir_dentry = dget_parent(lower_new_dentry);
+ target_inode = d_inode(new_dentry);
+ trap = lock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
+ /* source should not be ancestor of target */
+ if (trap == lower_old_dentry) {
+ rc = -EINVAL;
+ goto out_lock;
+ }
+ /* target should not be ancestor of source */
+ if (trap == lower_new_dentry) {
+ rc = -ENOTEMPTY;
+ goto out_lock;
+ }
+ rc = vfs_rename(d_inode(lower_old_dir_dentry), lower_old_dentry,
+ d_inode(lower_new_dir_dentry), lower_new_dentry,
+ NULL, 0);
+ if (rc)
+ goto out_lock;
+ if (target_inode)
+ fsstack_copy_attr_all(target_inode,
+ ecryptfs_inode_to_lower(target_inode));
+ fsstack_copy_attr_all(new_dir, d_inode(lower_new_dir_dentry));
+ if (new_dir != old_dir)
+ fsstack_copy_attr_all(old_dir, d_inode(lower_old_dir_dentry));
+out_lock:
+ unlock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
+ dput(lower_new_dir_dentry);
+ dput(lower_old_dir_dentry);
+ dput(lower_new_dentry);
+ dput(lower_old_dentry);
+ return rc;
+}
+
+static char *ecryptfs_readlink_lower(struct dentry *dentry, size_t *bufsiz)
+{
+ DEFINE_DELAYED_CALL(done);
+ struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
+ const char *link;
+ char *buf;
+ int rc;
+
+ link = vfs_get_link(lower_dentry, &done);
+ if (IS_ERR(link))
+ return ERR_CAST(link);
+
+ rc = ecryptfs_decode_and_decrypt_filename(&buf, bufsiz, dentry->d_sb,
+ link, strlen(link));
+ do_delayed_call(&done);
+ if (rc)
+ return ERR_PTR(rc);
+
+ return buf;
+}
+
+static const char *ecryptfs_get_link(struct dentry *dentry,
+ struct inode *inode,
+ struct delayed_call *done)
+{
+ size_t len;
+ char *buf;
+
+ if (!dentry)
+ return ERR_PTR(-ECHILD);
+
+ buf = ecryptfs_readlink_lower(dentry, &len);
+ if (IS_ERR(buf))
+ return buf;
+ fsstack_copy_attr_atime(d_inode(dentry),
+ d_inode(ecryptfs_dentry_to_lower(dentry)));
+ buf[len] = '\0';
+ set_delayed_call(done, kfree_link, buf);
+ return buf;
+}
+
+/**
+ * upper_size_to_lower_size
+ * @crypt_stat: Crypt_stat associated with file
+ * @upper_size: Size of the upper file
+ *
+ * Calculate the required size of the lower file based on the
+ * specified size of the upper file. This calculation is based on the
+ * number of headers in the underlying file and the extent size.
+ *
+ * Returns Calculated size of the lower file.
+ */
+static loff_t
+upper_size_to_lower_size(struct ecryptfs_crypt_stat *crypt_stat,
+ loff_t upper_size)
+{
+ loff_t lower_size;
+
+ lower_size = ecryptfs_lower_header_size(crypt_stat);
+ if (upper_size != 0) {
+ loff_t num_extents;
+
+ num_extents = upper_size >> crypt_stat->extent_shift;
+ if (upper_size & ~crypt_stat->extent_mask)
+ num_extents++;
+ lower_size += (num_extents * crypt_stat->extent_size);
+ }
+ return lower_size;
+}
+
+/**
+ * truncate_upper
+ * @dentry: The ecryptfs layer dentry
+ * @ia: Address of the ecryptfs inode's attributes
+ * @lower_ia: Address of the lower inode's attributes
+ *
+ * Function to handle truncations modifying the size of the file. Note
+ * that the file sizes are interpolated. When expanding, we are simply
+ * writing strings of 0's out. When truncating, we truncate the upper
+ * inode and update the lower_ia according to the page index
+ * interpolations. If ATTR_SIZE is set in lower_ia->ia_valid upon return,
+ * the caller must use lower_ia in a call to notify_change() to perform
+ * the truncation of the lower inode.
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+static int truncate_upper(struct dentry *dentry, struct iattr *ia,
+ struct iattr *lower_ia)
+{
+ int rc = 0;
+ struct inode *inode = d_inode(dentry);
+ struct ecryptfs_crypt_stat *crypt_stat;
+ loff_t i_size = i_size_read(inode);
+ loff_t lower_size_before_truncate;
+ loff_t lower_size_after_truncate;
+
+ if (unlikely((ia->ia_size == i_size))) {
+ lower_ia->ia_valid &= ~ATTR_SIZE;
+ return 0;
+ }
+ rc = ecryptfs_get_lower_file(dentry, inode);
+ if (rc)
+ return rc;
+ crypt_stat = &ecryptfs_inode_to_private(d_inode(dentry))->crypt_stat;
+ /* Switch on growing or shrinking file */
+ if (ia->ia_size > i_size) {
+ char zero[] = { 0x00 };
+
+ lower_ia->ia_valid &= ~ATTR_SIZE;
+ /* Write a single 0 at the last position of the file;
+ * this triggers code that will fill in 0's throughout
+ * the intermediate portion of the previous end of the
+ * file and the new and of the file */
+ rc = ecryptfs_write(inode, zero,
+ (ia->ia_size - 1), 1);
+ } else { /* ia->ia_size < i_size_read(inode) */
+ /* We're chopping off all the pages down to the page
+ * in which ia->ia_size is located. Fill in the end of
+ * that page from (ia->ia_size & ~PAGE_MASK) to
+ * PAGE_SIZE with zeros. */
+ size_t num_zeros = (PAGE_SIZE
+ - (ia->ia_size & ~PAGE_MASK));
+
+ if (!(crypt_stat->flags & ECRYPTFS_ENCRYPTED)) {
+ truncate_setsize(inode, ia->ia_size);
+ lower_ia->ia_size = ia->ia_size;
+ lower_ia->ia_valid |= ATTR_SIZE;
+ goto out;
+ }
+ if (num_zeros) {
+ char *zeros_virt;
+
+ zeros_virt = kzalloc(num_zeros, GFP_KERNEL);
+ if (!zeros_virt) {
+ rc = -ENOMEM;
+ goto out;
+ }
+ rc = ecryptfs_write(inode, zeros_virt,
+ ia->ia_size, num_zeros);
+ kfree(zeros_virt);
+ if (rc) {
+ printk(KERN_ERR "Error attempting to zero out "
+ "the remainder of the end page on "
+ "reducing truncate; rc = [%d]\n", rc);
+ goto out;
+ }
+ }
+ truncate_setsize(inode, ia->ia_size);
+ rc = ecryptfs_write_inode_size_to_metadata(inode);
+ if (rc) {
+ printk(KERN_ERR "Problem with "
+ "ecryptfs_write_inode_size_to_metadata; "
+ "rc = [%d]\n", rc);
+ goto out;
+ }
+ /* We are reducing the size of the ecryptfs file, and need to
+ * know if we need to reduce the size of the lower file. */
+ lower_size_before_truncate =
+ upper_size_to_lower_size(crypt_stat, i_size);
+ lower_size_after_truncate =
+ upper_size_to_lower_size(crypt_stat, ia->ia_size);
+ if (lower_size_after_truncate < lower_size_before_truncate) {
+ lower_ia->ia_size = lower_size_after_truncate;
+ lower_ia->ia_valid |= ATTR_SIZE;
+ } else
+ lower_ia->ia_valid &= ~ATTR_SIZE;
+ }
+out:
+ ecryptfs_put_lower_file(inode);
+ return rc;
+}
+
+static int ecryptfs_inode_newsize_ok(struct inode *inode, loff_t offset)
+{
+ struct ecryptfs_crypt_stat *crypt_stat;
+ loff_t lower_oldsize, lower_newsize;
+
+ crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat;
+ lower_oldsize = upper_size_to_lower_size(crypt_stat,
+ i_size_read(inode));
+ lower_newsize = upper_size_to_lower_size(crypt_stat, offset);
+ if (lower_newsize > lower_oldsize) {
+ /*
+ * The eCryptfs inode and the new *lower* size are mixed here
+ * because we may not have the lower i_mutex held and/or it may
+ * not be appropriate to call inode_newsize_ok() with inodes
+ * from other filesystems.
+ */
+ return inode_newsize_ok(inode, lower_newsize);
+ }
+
+ return 0;
+}
+
+/**
+ * ecryptfs_truncate
+ * @dentry: The ecryptfs layer dentry
+ * @new_length: The length to expand the file to
+ *
+ * Simple function that handles the truncation of an eCryptfs inode and
+ * its corresponding lower inode.
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+int ecryptfs_truncate(struct dentry *dentry, loff_t new_length)
+{
+ struct iattr ia = { .ia_valid = ATTR_SIZE, .ia_size = new_length };
+ struct iattr lower_ia = { .ia_valid = 0 };
+ int rc;
+
+ rc = ecryptfs_inode_newsize_ok(d_inode(dentry), new_length);
+ if (rc)
+ return rc;
+
+ rc = truncate_upper(dentry, &ia, &lower_ia);
+ if (!rc && lower_ia.ia_valid & ATTR_SIZE) {
+ struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
+
+ inode_lock(d_inode(lower_dentry));
+ rc = notify_change(lower_dentry, &lower_ia, NULL);
+ inode_unlock(d_inode(lower_dentry));
+ }
+ return rc;
+}
+
+static int
+ecryptfs_permission(struct inode *inode, int mask)
+{
+ return inode_permission(ecryptfs_inode_to_lower(inode), mask);
+}
+
+/**
+ * ecryptfs_setattr
+ * @dentry: dentry handle to the inode to modify
+ * @ia: Structure with flags of what to change and values
+ *
+ * Updates the metadata of an inode. If the update is to the size
+ * i.e. truncation, then ecryptfs_truncate will handle the size modification
+ * of both the ecryptfs inode and the lower inode.
+ *
+ * All other metadata changes will be passed right to the lower filesystem,
+ * and we will just update our inode to look like the lower.
+ */
+static int ecryptfs_setattr(struct dentry *dentry, struct iattr *ia)
+{
+ int rc = 0;
+ struct dentry *lower_dentry;
+ struct iattr lower_ia;
+ struct inode *inode;
+ struct inode *lower_inode;
+ struct ecryptfs_crypt_stat *crypt_stat;
+
+ crypt_stat = &ecryptfs_inode_to_private(d_inode(dentry))->crypt_stat;
+ if (!(crypt_stat->flags & ECRYPTFS_STRUCT_INITIALIZED)) {
+ rc = ecryptfs_init_crypt_stat(crypt_stat);
+ if (rc)
+ return rc;
+ }
+ inode = d_inode(dentry);
+ lower_inode = ecryptfs_inode_to_lower(inode);
+ lower_dentry = ecryptfs_dentry_to_lower(dentry);
+ mutex_lock(&crypt_stat->cs_mutex);
+ if (d_is_dir(dentry))
+ crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED);
+ else if (d_is_reg(dentry)
+ && (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED)
+ || !(crypt_stat->flags & ECRYPTFS_KEY_VALID))) {
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
+
+ mount_crypt_stat = &ecryptfs_superblock_to_private(
+ dentry->d_sb)->mount_crypt_stat;
+ rc = ecryptfs_get_lower_file(dentry, inode);
+ if (rc) {
+ mutex_unlock(&crypt_stat->cs_mutex);
+ goto out;
+ }
+ rc = ecryptfs_read_metadata(dentry);
+ ecryptfs_put_lower_file(inode);
+ if (rc) {
+ if (!(mount_crypt_stat->flags
+ & ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED)) {
+ rc = -EIO;
+ printk(KERN_WARNING "Either the lower file "
+ "is not in a valid eCryptfs format, "
+ "or the key could not be retrieved. "
+ "Plaintext passthrough mode is not "
+ "enabled; returning -EIO\n");
+ mutex_unlock(&crypt_stat->cs_mutex);
+ goto out;
+ }
+ rc = 0;
+ crypt_stat->flags &= ~(ECRYPTFS_I_SIZE_INITIALIZED
+ | ECRYPTFS_ENCRYPTED);
+ }
+ }
+ mutex_unlock(&crypt_stat->cs_mutex);
+
+ rc = setattr_prepare(dentry, ia);
+ if (rc)
+ goto out;
+ if (ia->ia_valid & ATTR_SIZE) {
+ rc = ecryptfs_inode_newsize_ok(inode, ia->ia_size);
+ if (rc)
+ goto out;
+ }
+
+ memcpy(&lower_ia, ia, sizeof(lower_ia));
+ if (ia->ia_valid & ATTR_FILE)
+ lower_ia.ia_file = ecryptfs_file_to_lower(ia->ia_file);
+ if (ia->ia_valid & ATTR_SIZE) {
+ rc = truncate_upper(dentry, ia, &lower_ia);
+ if (rc < 0)
+ goto out;
+ }
+
+ /*
+ * mode change is for clearing setuid/setgid bits. Allow lower fs
+ * to interpret this in its own way.
+ */
+ if (lower_ia.ia_valid & (ATTR_KILL_SUID | ATTR_KILL_SGID))
+ lower_ia.ia_valid &= ~ATTR_MODE;
+
+ inode_lock(d_inode(lower_dentry));
+ rc = notify_change(lower_dentry, &lower_ia, NULL);
+ inode_unlock(d_inode(lower_dentry));
+out:
+ fsstack_copy_attr_all(inode, lower_inode);
+ return rc;
+}
+
+static int ecryptfs_getattr_link(const struct path *path, struct kstat *stat,
+ u32 request_mask, unsigned int flags)
+{
+ struct dentry *dentry = path->dentry;
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
+ int rc = 0;
+
+ mount_crypt_stat = &ecryptfs_superblock_to_private(
+ dentry->d_sb)->mount_crypt_stat;
+ generic_fillattr(d_inode(dentry), stat);
+ if (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES) {
+ char *target;
+ size_t targetsiz;
+
+ target = ecryptfs_readlink_lower(dentry, &targetsiz);
+ if (!IS_ERR(target)) {
+ kfree(target);
+ stat->size = targetsiz;
+ } else {
+ rc = PTR_ERR(target);
+ }
+ }
+ return rc;
+}
+
+static int ecryptfs_getattr(const struct path *path, struct kstat *stat,
+ u32 request_mask, unsigned int flags)
+{
+ struct dentry *dentry = path->dentry;
+ struct kstat lower_stat;
+ int rc;
+
+ rc = vfs_getattr(ecryptfs_dentry_to_lower_path(dentry), &lower_stat,
+ request_mask, flags);
+ if (!rc) {
+ fsstack_copy_attr_all(d_inode(dentry),
+ ecryptfs_inode_to_lower(d_inode(dentry)));
+ generic_fillattr(d_inode(dentry), stat);
+ stat->blocks = lower_stat.blocks;
+ }
+ return rc;
+}
+
+int
+ecryptfs_setxattr(struct dentry *dentry, struct inode *inode,
+ const char *name, const void *value,
+ size_t size, int flags)
+{
+ int rc;
+ struct dentry *lower_dentry;
+
+ lower_dentry = ecryptfs_dentry_to_lower(dentry);
+ if (!(d_inode(lower_dentry)->i_opflags & IOP_XATTR)) {
+ rc = -EOPNOTSUPP;
+ goto out;
+ }
+ rc = vfs_setxattr(lower_dentry, name, value, size, flags);
+ if (!rc && inode)
+ fsstack_copy_attr_all(inode, d_inode(lower_dentry));
+out:
+ return rc;
+}
+
+ssize_t
+ecryptfs_getxattr_lower(struct dentry *lower_dentry, struct inode *lower_inode,
+ const char *name, void *value, size_t size)
+{
+ int rc;
+
+ if (!(lower_inode->i_opflags & IOP_XATTR)) {
+ rc = -EOPNOTSUPP;
+ goto out;
+ }
+ inode_lock(lower_inode);
+ rc = __vfs_getxattr(lower_dentry, lower_inode, name, value, size);
+ inode_unlock(lower_inode);
+out:
+ return rc;
+}
+
+static ssize_t
+ecryptfs_getxattr(struct dentry *dentry, struct inode *inode,
+ const char *name, void *value, size_t size)
+{
+ return ecryptfs_getxattr_lower(ecryptfs_dentry_to_lower(dentry),
+ ecryptfs_inode_to_lower(inode),
+ name, value, size);
+}
+
+static ssize_t
+ecryptfs_listxattr(struct dentry *dentry, char *list, size_t size)
+{
+ int rc = 0;
+ struct dentry *lower_dentry;
+
+ lower_dentry = ecryptfs_dentry_to_lower(dentry);
+ if (!d_inode(lower_dentry)->i_op->listxattr) {
+ rc = -EOPNOTSUPP;
+ goto out;
+ }
+ inode_lock(d_inode(lower_dentry));
+ rc = d_inode(lower_dentry)->i_op->listxattr(lower_dentry, list, size);
+ inode_unlock(d_inode(lower_dentry));
+out:
+ return rc;
+}
+
+static int ecryptfs_removexattr(struct dentry *dentry, struct inode *inode,
+ const char *name)
+{
+ int rc;
+ struct dentry *lower_dentry;
+ struct inode *lower_inode;
+
+ lower_dentry = ecryptfs_dentry_to_lower(dentry);
+ lower_inode = ecryptfs_inode_to_lower(inode);
+ if (!(lower_inode->i_opflags & IOP_XATTR)) {
+ rc = -EOPNOTSUPP;
+ goto out;
+ }
+ inode_lock(lower_inode);
+ rc = __vfs_removexattr(lower_dentry, name);
+ inode_unlock(lower_inode);
+out:
+ return rc;
+}
+
+const struct inode_operations ecryptfs_symlink_iops = {
+ .get_link = ecryptfs_get_link,
+ .permission = ecryptfs_permission,
+ .setattr = ecryptfs_setattr,
+ .getattr = ecryptfs_getattr_link,
+ .listxattr = ecryptfs_listxattr,
+};
+
+const struct inode_operations ecryptfs_dir_iops = {
+ .create = ecryptfs_create,
+ .lookup = ecryptfs_lookup,
+ .link = ecryptfs_link,
+ .unlink = ecryptfs_unlink,
+ .symlink = ecryptfs_symlink,
+ .mkdir = ecryptfs_mkdir,
+ .rmdir = ecryptfs_rmdir,
+ .mknod = ecryptfs_mknod,
+ .rename = ecryptfs_rename,
+ .permission = ecryptfs_permission,
+ .setattr = ecryptfs_setattr,
+ .listxattr = ecryptfs_listxattr,
+};
+
+const struct inode_operations ecryptfs_main_iops = {
+ .permission = ecryptfs_permission,
+ .setattr = ecryptfs_setattr,
+ .getattr = ecryptfs_getattr,
+ .listxattr = ecryptfs_listxattr,
+};
+
+static int ecryptfs_xattr_get(const struct xattr_handler *handler,
+ struct dentry *dentry, struct inode *inode,
+ const char *name, void *buffer, size_t size)
+{
+ return ecryptfs_getxattr(dentry, inode, name, buffer, size);
+}
+
+static int ecryptfs_xattr_set(const struct xattr_handler *handler,
+ struct dentry *dentry, struct inode *inode,
+ const char *name, const void *value, size_t size,
+ int flags)
+{
+ if (value)
+ return ecryptfs_setxattr(dentry, inode, name, value, size, flags);
+ else {
+ BUG_ON(flags != XATTR_REPLACE);
+ return ecryptfs_removexattr(dentry, inode, name);
+ }
+}
+
+const struct xattr_handler ecryptfs_xattr_handler = {
+ .prefix = "", /* match anything */
+ .get = ecryptfs_xattr_get,
+ .set = ecryptfs_xattr_set,
+};
+
+const struct xattr_handler *ecryptfs_xattr_handlers[] = {
+ &ecryptfs_xattr_handler,
+ NULL
+};
diff --git a/fs/ecryptfs/keystore.c b/fs/ecryptfs/keystore.c
new file mode 100644
index 0000000..e74fe84
--- /dev/null
+++ b/fs/ecryptfs/keystore.c
@@ -0,0 +1,2544 @@
+/**
+ * eCryptfs: Linux filesystem encryption layer
+ * In-kernel key management code. Includes functions to parse and
+ * write authentication token-related packets with the underlying
+ * file.
+ *
+ * Copyright (C) 2004-2006 International Business Machines Corp.
+ * Author(s): Michael A. Halcrow <mhalcrow@us.ibm.com>
+ * Michael C. Thompson <mcthomps@us.ibm.com>
+ * Trevor S. Highland <trevor.highland@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ */
+
+#include <crypto/hash.h>
+#include <crypto/skcipher.h>
+#include <linux/string.h>
+#include <linux/pagemap.h>
+#include <linux/key.h>
+#include <linux/random.h>
+#include <linux/scatterlist.h>
+#include <linux/slab.h>
+#include "ecryptfs_kernel.h"
+
+/**
+ * request_key returned an error instead of a valid key address;
+ * determine the type of error, make appropriate log entries, and
+ * return an error code.
+ */
+static int process_request_key_err(long err_code)
+{
+ int rc = 0;
+
+ switch (err_code) {
+ case -ENOKEY:
+ ecryptfs_printk(KERN_WARNING, "No key\n");
+ rc = -ENOENT;
+ break;
+ case -EKEYEXPIRED:
+ ecryptfs_printk(KERN_WARNING, "Key expired\n");
+ rc = -ETIME;
+ break;
+ case -EKEYREVOKED:
+ ecryptfs_printk(KERN_WARNING, "Key revoked\n");
+ rc = -EINVAL;
+ break;
+ default:
+ ecryptfs_printk(KERN_WARNING, "Unknown error code: "
+ "[0x%.16lx]\n", err_code);
+ rc = -EINVAL;
+ }
+ return rc;
+}
+
+static int process_find_global_auth_tok_for_sig_err(int err_code)
+{
+ int rc = err_code;
+
+ switch (err_code) {
+ case -ENOENT:
+ ecryptfs_printk(KERN_WARNING, "Missing auth tok\n");
+ break;
+ case -EINVAL:
+ ecryptfs_printk(KERN_WARNING, "Invalid auth tok\n");
+ break;
+ default:
+ rc = process_request_key_err(err_code);
+ break;
+ }
+ return rc;
+}
+
+/**
+ * ecryptfs_parse_packet_length
+ * @data: Pointer to memory containing length at offset
+ * @size: This function writes the decoded size to this memory
+ * address; zero on error
+ * @length_size: The number of bytes occupied by the encoded length
+ *
+ * Returns zero on success; non-zero on error
+ */
+int ecryptfs_parse_packet_length(unsigned char *data, size_t *size,
+ size_t *length_size)
+{
+ int rc = 0;
+
+ (*length_size) = 0;
+ (*size) = 0;
+ if (data[0] < 192) {
+ /* One-byte length */
+ (*size) = data[0];
+ (*length_size) = 1;
+ } else if (data[0] < 224) {
+ /* Two-byte length */
+ (*size) = (data[0] - 192) * 256;
+ (*size) += data[1] + 192;
+ (*length_size) = 2;
+ } else if (data[0] == 255) {
+ /* If support is added, adjust ECRYPTFS_MAX_PKT_LEN_SIZE */
+ ecryptfs_printk(KERN_ERR, "Five-byte packet length not "
+ "supported\n");
+ rc = -EINVAL;
+ goto out;
+ } else {
+ ecryptfs_printk(KERN_ERR, "Error parsing packet length\n");
+ rc = -EINVAL;
+ goto out;
+ }
+out:
+ return rc;
+}
+
+/**
+ * ecryptfs_write_packet_length
+ * @dest: The byte array target into which to write the length. Must
+ * have at least ECRYPTFS_MAX_PKT_LEN_SIZE bytes allocated.
+ * @size: The length to write.
+ * @packet_size_length: The number of bytes used to encode the packet
+ * length is written to this address.
+ *
+ * Returns zero on success; non-zero on error.
+ */
+int ecryptfs_write_packet_length(char *dest, size_t size,
+ size_t *packet_size_length)
+{
+ int rc = 0;
+
+ if (size < 192) {
+ dest[0] = size;
+ (*packet_size_length) = 1;
+ } else if (size < 65536) {
+ dest[0] = (((size - 192) / 256) + 192);
+ dest[1] = ((size - 192) % 256);
+ (*packet_size_length) = 2;
+ } else {
+ /* If support is added, adjust ECRYPTFS_MAX_PKT_LEN_SIZE */
+ rc = -EINVAL;
+ ecryptfs_printk(KERN_WARNING,
+ "Unsupported packet size: [%zd]\n", size);
+ }
+ return rc;
+}
+
+static int
+write_tag_64_packet(char *signature, struct ecryptfs_session_key *session_key,
+ char **packet, size_t *packet_len)
+{
+ size_t i = 0;
+ size_t data_len;
+ size_t packet_size_len;
+ char *message;
+ int rc;
+
+ /*
+ * ***** TAG 64 Packet Format *****
+ * | Content Type | 1 byte |
+ * | Key Identifier Size | 1 or 2 bytes |
+ * | Key Identifier | arbitrary |
+ * | Encrypted File Encryption Key Size | 1 or 2 bytes |
+ * | Encrypted File Encryption Key | arbitrary |
+ */
+ data_len = (5 + ECRYPTFS_SIG_SIZE_HEX
+ + session_key->encrypted_key_size);
+ *packet = kmalloc(data_len, GFP_KERNEL);
+ message = *packet;
+ if (!message) {
+ ecryptfs_printk(KERN_ERR, "Unable to allocate memory\n");
+ rc = -ENOMEM;
+ goto out;
+ }
+ message[i++] = ECRYPTFS_TAG_64_PACKET_TYPE;
+ rc = ecryptfs_write_packet_length(&message[i], ECRYPTFS_SIG_SIZE_HEX,
+ &packet_size_len);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error generating tag 64 packet "
+ "header; cannot generate packet length\n");
+ goto out;
+ }
+ i += packet_size_len;
+ memcpy(&message[i], signature, ECRYPTFS_SIG_SIZE_HEX);
+ i += ECRYPTFS_SIG_SIZE_HEX;
+ rc = ecryptfs_write_packet_length(&message[i],
+ session_key->encrypted_key_size,
+ &packet_size_len);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error generating tag 64 packet "
+ "header; cannot generate packet length\n");
+ goto out;
+ }
+ i += packet_size_len;
+ memcpy(&message[i], session_key->encrypted_key,
+ session_key->encrypted_key_size);
+ i += session_key->encrypted_key_size;
+ *packet_len = i;
+out:
+ return rc;
+}
+
+static int
+parse_tag_65_packet(struct ecryptfs_session_key *session_key, u8 *cipher_code,
+ struct ecryptfs_message *msg)
+{
+ size_t i = 0;
+ char *data;
+ size_t data_len;
+ size_t m_size;
+ size_t message_len;
+ u16 checksum = 0;
+ u16 expected_checksum = 0;
+ int rc;
+
+ /*
+ * ***** TAG 65 Packet Format *****
+ * | Content Type | 1 byte |
+ * | Status Indicator | 1 byte |
+ * | File Encryption Key Size | 1 or 2 bytes |
+ * | File Encryption Key | arbitrary |
+ */
+ message_len = msg->data_len;
+ data = msg->data;
+ if (message_len < 4) {
+ rc = -EIO;
+ goto out;
+ }
+ if (data[i++] != ECRYPTFS_TAG_65_PACKET_TYPE) {
+ ecryptfs_printk(KERN_ERR, "Type should be ECRYPTFS_TAG_65\n");
+ rc = -EIO;
+ goto out;
+ }
+ if (data[i++]) {
+ ecryptfs_printk(KERN_ERR, "Status indicator has non-zero value "
+ "[%d]\n", data[i-1]);
+ rc = -EIO;
+ goto out;
+ }
+ rc = ecryptfs_parse_packet_length(&data[i], &m_size, &data_len);
+ if (rc) {
+ ecryptfs_printk(KERN_WARNING, "Error parsing packet length; "
+ "rc = [%d]\n", rc);
+ goto out;
+ }
+ i += data_len;
+ if (message_len < (i + m_size)) {
+ ecryptfs_printk(KERN_ERR, "The message received from ecryptfsd "
+ "is shorter than expected\n");
+ rc = -EIO;
+ goto out;
+ }
+ if (m_size < 3) {
+ ecryptfs_printk(KERN_ERR,
+ "The decrypted key is not long enough to "
+ "include a cipher code and checksum\n");
+ rc = -EIO;
+ goto out;
+ }
+ *cipher_code = data[i++];
+ /* The decrypted key includes 1 byte cipher code and 2 byte checksum */
+ session_key->decrypted_key_size = m_size - 3;
+ if (session_key->decrypted_key_size > ECRYPTFS_MAX_KEY_BYTES) {
+ ecryptfs_printk(KERN_ERR, "key_size [%d] larger than "
+ "the maximum key size [%d]\n",
+ session_key->decrypted_key_size,
+ ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES);
+ rc = -EIO;
+ goto out;
+ }
+ memcpy(session_key->decrypted_key, &data[i],
+ session_key->decrypted_key_size);
+ i += session_key->decrypted_key_size;
+ expected_checksum += (unsigned char)(data[i++]) << 8;
+ expected_checksum += (unsigned char)(data[i++]);
+ for (i = 0; i < session_key->decrypted_key_size; i++)
+ checksum += session_key->decrypted_key[i];
+ if (expected_checksum != checksum) {
+ ecryptfs_printk(KERN_ERR, "Invalid checksum for file "
+ "encryption key; expected [%x]; calculated "
+ "[%x]\n", expected_checksum, checksum);
+ rc = -EIO;
+ }
+out:
+ return rc;
+}
+
+
+static int
+write_tag_66_packet(char *signature, u8 cipher_code,
+ struct ecryptfs_crypt_stat *crypt_stat, char **packet,
+ size_t *packet_len)
+{
+ size_t i = 0;
+ size_t j;
+ size_t data_len;
+ size_t checksum = 0;
+ size_t packet_size_len;
+ char *message;
+ int rc;
+
+ /*
+ * ***** TAG 66 Packet Format *****
+ * | Content Type | 1 byte |
+ * | Key Identifier Size | 1 or 2 bytes |
+ * | Key Identifier | arbitrary |
+ * | File Encryption Key Size | 1 or 2 bytes |
+ * | File Encryption Key | arbitrary |
+ */
+ data_len = (5 + ECRYPTFS_SIG_SIZE_HEX + crypt_stat->key_size);
+ *packet = kmalloc(data_len, GFP_KERNEL);
+ message = *packet;
+ if (!message) {
+ ecryptfs_printk(KERN_ERR, "Unable to allocate memory\n");
+ rc = -ENOMEM;
+ goto out;
+ }
+ message[i++] = ECRYPTFS_TAG_66_PACKET_TYPE;
+ rc = ecryptfs_write_packet_length(&message[i], ECRYPTFS_SIG_SIZE_HEX,
+ &packet_size_len);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error generating tag 66 packet "
+ "header; cannot generate packet length\n");
+ goto out;
+ }
+ i += packet_size_len;
+ memcpy(&message[i], signature, ECRYPTFS_SIG_SIZE_HEX);
+ i += ECRYPTFS_SIG_SIZE_HEX;
+ /* The encrypted key includes 1 byte cipher code and 2 byte checksum */
+ rc = ecryptfs_write_packet_length(&message[i], crypt_stat->key_size + 3,
+ &packet_size_len);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error generating tag 66 packet "
+ "header; cannot generate packet length\n");
+ goto out;
+ }
+ i += packet_size_len;
+ message[i++] = cipher_code;
+ memcpy(&message[i], crypt_stat->key, crypt_stat->key_size);
+ i += crypt_stat->key_size;
+ for (j = 0; j < crypt_stat->key_size; j++)
+ checksum += crypt_stat->key[j];
+ message[i++] = (checksum / 256) % 256;
+ message[i++] = (checksum % 256);
+ *packet_len = i;
+out:
+ return rc;
+}
+
+static int
+parse_tag_67_packet(struct ecryptfs_key_record *key_rec,
+ struct ecryptfs_message *msg)
+{
+ size_t i = 0;
+ char *data;
+ size_t data_len;
+ size_t message_len;
+ int rc;
+
+ /*
+ * ***** TAG 65 Packet Format *****
+ * | Content Type | 1 byte |
+ * | Status Indicator | 1 byte |
+ * | Encrypted File Encryption Key Size | 1 or 2 bytes |
+ * | Encrypted File Encryption Key | arbitrary |
+ */
+ message_len = msg->data_len;
+ data = msg->data;
+ /* verify that everything through the encrypted FEK size is present */
+ if (message_len < 4) {
+ rc = -EIO;
+ printk(KERN_ERR "%s: message_len is [%zd]; minimum acceptable "
+ "message length is [%d]\n", __func__, message_len, 4);
+ goto out;
+ }
+ if (data[i++] != ECRYPTFS_TAG_67_PACKET_TYPE) {
+ rc = -EIO;
+ printk(KERN_ERR "%s: Type should be ECRYPTFS_TAG_67\n",
+ __func__);
+ goto out;
+ }
+ if (data[i++]) {
+ rc = -EIO;
+ printk(KERN_ERR "%s: Status indicator has non zero "
+ "value [%d]\n", __func__, data[i-1]);
+
+ goto out;
+ }
+ rc = ecryptfs_parse_packet_length(&data[i], &key_rec->enc_key_size,
+ &data_len);
+ if (rc) {
+ ecryptfs_printk(KERN_WARNING, "Error parsing packet length; "
+ "rc = [%d]\n", rc);
+ goto out;
+ }
+ i += data_len;
+ if (message_len < (i + key_rec->enc_key_size)) {
+ rc = -EIO;
+ printk(KERN_ERR "%s: message_len [%zd]; max len is [%zd]\n",
+ __func__, message_len, (i + key_rec->enc_key_size));
+ goto out;
+ }
+ if (key_rec->enc_key_size > ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES) {
+ rc = -EIO;
+ printk(KERN_ERR "%s: Encrypted key_size [%zd] larger than "
+ "the maximum key size [%d]\n", __func__,
+ key_rec->enc_key_size,
+ ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES);
+ goto out;
+ }
+ memcpy(key_rec->enc_key, &data[i], key_rec->enc_key_size);
+out:
+ return rc;
+}
+
+/**
+ * ecryptfs_verify_version
+ * @version: The version number to confirm
+ *
+ * Returns zero on good version; non-zero otherwise
+ */
+static int ecryptfs_verify_version(u16 version)
+{
+ int rc = 0;
+ unsigned char major;
+ unsigned char minor;
+
+ major = ((version >> 8) & 0xFF);
+ minor = (version & 0xFF);
+ if (major != ECRYPTFS_VERSION_MAJOR) {
+ ecryptfs_printk(KERN_ERR, "Major version number mismatch. "
+ "Expected [%d]; got [%d]\n",
+ ECRYPTFS_VERSION_MAJOR, major);
+ rc = -EINVAL;
+ goto out;
+ }
+ if (minor != ECRYPTFS_VERSION_MINOR) {
+ ecryptfs_printk(KERN_ERR, "Minor version number mismatch. "
+ "Expected [%d]; got [%d]\n",
+ ECRYPTFS_VERSION_MINOR, minor);
+ rc = -EINVAL;
+ goto out;
+ }
+out:
+ return rc;
+}
+
+/**
+ * ecryptfs_verify_auth_tok_from_key
+ * @auth_tok_key: key containing the authentication token
+ * @auth_tok: authentication token
+ *
+ * Returns zero on valid auth tok; -EINVAL if the payload is invalid; or
+ * -EKEYREVOKED if the key was revoked before we acquired its semaphore.
+ */
+static int
+ecryptfs_verify_auth_tok_from_key(struct key *auth_tok_key,
+ struct ecryptfs_auth_tok **auth_tok)
+{
+ int rc = 0;
+
+ (*auth_tok) = ecryptfs_get_key_payload_data(auth_tok_key);
+ if (IS_ERR(*auth_tok)) {
+ rc = PTR_ERR(*auth_tok);
+ *auth_tok = NULL;
+ goto out;
+ }
+
+ if (ecryptfs_verify_version((*auth_tok)->version)) {
+ printk(KERN_ERR "Data structure version mismatch. Userspace "
+ "tools must match eCryptfs kernel module with major "
+ "version [%d] and minor version [%d]\n",
+ ECRYPTFS_VERSION_MAJOR, ECRYPTFS_VERSION_MINOR);
+ rc = -EINVAL;
+ goto out;
+ }
+ if ((*auth_tok)->token_type != ECRYPTFS_PASSWORD
+ && (*auth_tok)->token_type != ECRYPTFS_PRIVATE_KEY) {
+ printk(KERN_ERR "Invalid auth_tok structure "
+ "returned from key query\n");
+ rc = -EINVAL;
+ goto out;
+ }
+out:
+ return rc;
+}
+
+static int
+ecryptfs_find_global_auth_tok_for_sig(
+ struct key **auth_tok_key,
+ struct ecryptfs_auth_tok **auth_tok,
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat, char *sig)
+{
+ struct ecryptfs_global_auth_tok *walker;
+ int rc = 0;
+
+ (*auth_tok_key) = NULL;
+ (*auth_tok) = NULL;
+ mutex_lock(&mount_crypt_stat->global_auth_tok_list_mutex);
+ list_for_each_entry(walker,
+ &mount_crypt_stat->global_auth_tok_list,
+ mount_crypt_stat_list) {
+ if (memcmp(walker->sig, sig, ECRYPTFS_SIG_SIZE_HEX))
+ continue;
+
+ if (walker->flags & ECRYPTFS_AUTH_TOK_INVALID) {
+ rc = -EINVAL;
+ goto out;
+ }
+
+ rc = key_validate(walker->global_auth_tok_key);
+ if (rc) {
+ if (rc == -EKEYEXPIRED)
+ goto out;
+ goto out_invalid_auth_tok;
+ }
+
+ down_write(&(walker->global_auth_tok_key->sem));
+ rc = ecryptfs_verify_auth_tok_from_key(
+ walker->global_auth_tok_key, auth_tok);
+ if (rc)
+ goto out_invalid_auth_tok_unlock;
+
+ (*auth_tok_key) = walker->global_auth_tok_key;
+ key_get(*auth_tok_key);
+ goto out;
+ }
+ rc = -ENOENT;
+ goto out;
+out_invalid_auth_tok_unlock:
+ up_write(&(walker->global_auth_tok_key->sem));
+out_invalid_auth_tok:
+ printk(KERN_WARNING "Invalidating auth tok with sig = [%s]\n", sig);
+ walker->flags |= ECRYPTFS_AUTH_TOK_INVALID;
+ key_put(walker->global_auth_tok_key);
+ walker->global_auth_tok_key = NULL;
+out:
+ mutex_unlock(&mount_crypt_stat->global_auth_tok_list_mutex);
+ return rc;
+}
+
+/**
+ * ecryptfs_find_auth_tok_for_sig
+ * @auth_tok: Set to the matching auth_tok; NULL if not found
+ * @crypt_stat: inode crypt_stat crypto context
+ * @sig: Sig of auth_tok to find
+ *
+ * For now, this function simply looks at the registered auth_tok's
+ * linked off the mount_crypt_stat, so all the auth_toks that can be
+ * used must be registered at mount time. This function could
+ * potentially try a lot harder to find auth_tok's (e.g., by calling
+ * out to ecryptfsd to dynamically retrieve an auth_tok object) so
+ * that static registration of auth_tok's will no longer be necessary.
+ *
+ * Returns zero on no error; non-zero on error
+ */
+static int
+ecryptfs_find_auth_tok_for_sig(
+ struct key **auth_tok_key,
+ struct ecryptfs_auth_tok **auth_tok,
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
+ char *sig)
+{
+ int rc = 0;
+
+ rc = ecryptfs_find_global_auth_tok_for_sig(auth_tok_key, auth_tok,
+ mount_crypt_stat, sig);
+ if (rc == -ENOENT) {
+ /* if the flag ECRYPTFS_GLOBAL_MOUNT_AUTH_TOK_ONLY is set in the
+ * mount_crypt_stat structure, we prevent to use auth toks that
+ * are not inserted through the ecryptfs_add_global_auth_tok
+ * function.
+ */
+ if (mount_crypt_stat->flags
+ & ECRYPTFS_GLOBAL_MOUNT_AUTH_TOK_ONLY)
+ return -EINVAL;
+
+ rc = ecryptfs_keyring_auth_tok_for_sig(auth_tok_key, auth_tok,
+ sig);
+ }
+ return rc;
+}
+
+/**
+ * write_tag_70_packet can gobble a lot of stack space. We stuff most
+ * of the function's parameters in a kmalloc'd struct to help reduce
+ * eCryptfs' overall stack usage.
+ */
+struct ecryptfs_write_tag_70_packet_silly_stack {
+ u8 cipher_code;
+ size_t max_packet_size;
+ size_t packet_size_len;
+ size_t block_aligned_filename_size;
+ size_t block_size;
+ size_t i;
+ size_t j;
+ size_t num_rand_bytes;
+ struct mutex *tfm_mutex;
+ char *block_aligned_filename;
+ struct ecryptfs_auth_tok *auth_tok;
+ struct scatterlist src_sg[2];
+ struct scatterlist dst_sg[2];
+ struct crypto_skcipher *skcipher_tfm;
+ struct skcipher_request *skcipher_req;
+ char iv[ECRYPTFS_MAX_IV_BYTES];
+ char hash[ECRYPTFS_TAG_70_DIGEST_SIZE];
+ char tmp_hash[ECRYPTFS_TAG_70_DIGEST_SIZE];
+ struct crypto_shash *hash_tfm;
+ struct shash_desc *hash_desc;
+};
+
+/**
+ * write_tag_70_packet - Write encrypted filename (EFN) packet against FNEK
+ * @filename: NULL-terminated filename string
+ *
+ * This is the simplest mechanism for achieving filename encryption in
+ * eCryptfs. It encrypts the given filename with the mount-wide
+ * filename encryption key (FNEK) and stores it in a packet to @dest,
+ * which the callee will encode and write directly into the dentry
+ * name.
+ */
+int
+ecryptfs_write_tag_70_packet(char *dest, size_t *remaining_bytes,
+ size_t *packet_size,
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
+ char *filename, size_t filename_size)
+{
+ struct ecryptfs_write_tag_70_packet_silly_stack *s;
+ struct key *auth_tok_key = NULL;
+ int rc = 0;
+
+ s = kzalloc(sizeof(*s), GFP_KERNEL);
+ if (!s)
+ return -ENOMEM;
+
+ (*packet_size) = 0;
+ rc = ecryptfs_find_auth_tok_for_sig(
+ &auth_tok_key,
+ &s->auth_tok, mount_crypt_stat,
+ mount_crypt_stat->global_default_fnek_sig);
+ if (rc) {
+ printk(KERN_ERR "%s: Error attempting to find auth tok for "
+ "fnek sig [%s]; rc = [%d]\n", __func__,
+ mount_crypt_stat->global_default_fnek_sig, rc);
+ goto out;
+ }
+ rc = ecryptfs_get_tfm_and_mutex_for_cipher_name(
+ &s->skcipher_tfm,
+ &s->tfm_mutex, mount_crypt_stat->global_default_fn_cipher_name);
+ if (unlikely(rc)) {
+ printk(KERN_ERR "Internal error whilst attempting to get "
+ "tfm and mutex for cipher name [%s]; rc = [%d]\n",
+ mount_crypt_stat->global_default_fn_cipher_name, rc);
+ goto out;
+ }
+ mutex_lock(s->tfm_mutex);
+ s->block_size = crypto_skcipher_blocksize(s->skcipher_tfm);
+ /* Plus one for the \0 separator between the random prefix
+ * and the plaintext filename */
+ s->num_rand_bytes = (ECRYPTFS_FILENAME_MIN_RANDOM_PREPEND_BYTES + 1);
+ s->block_aligned_filename_size = (s->num_rand_bytes + filename_size);
+ if ((s->block_aligned_filename_size % s->block_size) != 0) {
+ s->num_rand_bytes += (s->block_size
+ - (s->block_aligned_filename_size
+ % s->block_size));
+ s->block_aligned_filename_size = (s->num_rand_bytes
+ + filename_size);
+ }
+ /* Octet 0: Tag 70 identifier
+ * Octets 1-N1: Tag 70 packet size (includes cipher identifier
+ * and block-aligned encrypted filename size)
+ * Octets N1-N2: FNEK sig (ECRYPTFS_SIG_SIZE)
+ * Octet N2-N3: Cipher identifier (1 octet)
+ * Octets N3-N4: Block-aligned encrypted filename
+ * - Consists of a minimum number of random characters, a \0
+ * separator, and then the filename */
+ s->max_packet_size = (ECRYPTFS_TAG_70_MAX_METADATA_SIZE
+ + s->block_aligned_filename_size);
+ if (!dest) {
+ (*packet_size) = s->max_packet_size;
+ goto out_unlock;
+ }
+ if (s->max_packet_size > (*remaining_bytes)) {
+ printk(KERN_WARNING "%s: Require [%zd] bytes to write; only "
+ "[%zd] available\n", __func__, s->max_packet_size,
+ (*remaining_bytes));
+ rc = -EINVAL;
+ goto out_unlock;
+ }
+
+ s->skcipher_req = skcipher_request_alloc(s->skcipher_tfm, GFP_KERNEL);
+ if (!s->skcipher_req) {
+ printk(KERN_ERR "%s: Out of kernel memory whilst attempting to "
+ "skcipher_request_alloc for %s\n", __func__,
+ crypto_skcipher_driver_name(s->skcipher_tfm));
+ rc = -ENOMEM;
+ goto out_unlock;
+ }
+
+ skcipher_request_set_callback(s->skcipher_req,
+ CRYPTO_TFM_REQ_MAY_SLEEP, NULL, NULL);
+
+ s->block_aligned_filename = kzalloc(s->block_aligned_filename_size,
+ GFP_KERNEL);
+ if (!s->block_aligned_filename) {
+ rc = -ENOMEM;
+ goto out_unlock;
+ }
+ dest[s->i++] = ECRYPTFS_TAG_70_PACKET_TYPE;
+ rc = ecryptfs_write_packet_length(&dest[s->i],
+ (ECRYPTFS_SIG_SIZE
+ + 1 /* Cipher code */
+ + s->block_aligned_filename_size),
+ &s->packet_size_len);
+ if (rc) {
+ printk(KERN_ERR "%s: Error generating tag 70 packet "
+ "header; cannot generate packet length; rc = [%d]\n",
+ __func__, rc);
+ goto out_free_unlock;
+ }
+ s->i += s->packet_size_len;
+ ecryptfs_from_hex(&dest[s->i],
+ mount_crypt_stat->global_default_fnek_sig,
+ ECRYPTFS_SIG_SIZE);
+ s->i += ECRYPTFS_SIG_SIZE;
+ s->cipher_code = ecryptfs_code_for_cipher_string(
+ mount_crypt_stat->global_default_fn_cipher_name,
+ mount_crypt_stat->global_default_fn_cipher_key_bytes);
+ if (s->cipher_code == 0) {
+ printk(KERN_WARNING "%s: Unable to generate code for "
+ "cipher [%s] with key bytes [%zd]\n", __func__,
+ mount_crypt_stat->global_default_fn_cipher_name,
+ mount_crypt_stat->global_default_fn_cipher_key_bytes);
+ rc = -EINVAL;
+ goto out_free_unlock;
+ }
+ dest[s->i++] = s->cipher_code;
+ /* TODO: Support other key modules than passphrase for
+ * filename encryption */
+ if (s->auth_tok->token_type != ECRYPTFS_PASSWORD) {
+ rc = -EOPNOTSUPP;
+ printk(KERN_INFO "%s: Filename encryption only supports "
+ "password tokens\n", __func__);
+ goto out_free_unlock;
+ }
+ s->hash_tfm = crypto_alloc_shash(ECRYPTFS_TAG_70_DIGEST, 0, 0);
+ if (IS_ERR(s->hash_tfm)) {
+ rc = PTR_ERR(s->hash_tfm);
+ printk(KERN_ERR "%s: Error attempting to "
+ "allocate hash crypto context; rc = [%d]\n",
+ __func__, rc);
+ goto out_free_unlock;
+ }
+
+ s->hash_desc = kmalloc(sizeof(*s->hash_desc) +
+ crypto_shash_descsize(s->hash_tfm), GFP_KERNEL);
+ if (!s->hash_desc) {
+ rc = -ENOMEM;
+ goto out_release_free_unlock;
+ }
+
+ s->hash_desc->tfm = s->hash_tfm;
+ s->hash_desc->flags = CRYPTO_TFM_REQ_MAY_SLEEP;
+
+ rc = crypto_shash_digest(s->hash_desc,
+ (u8 *)s->auth_tok->token.password.session_key_encryption_key,
+ s->auth_tok->token.password.session_key_encryption_key_bytes,
+ s->hash);
+ if (rc) {
+ printk(KERN_ERR
+ "%s: Error computing crypto hash; rc = [%d]\n",
+ __func__, rc);
+ goto out_release_free_unlock;
+ }
+ for (s->j = 0; s->j < (s->num_rand_bytes - 1); s->j++) {
+ s->block_aligned_filename[s->j] =
+ s->hash[(s->j % ECRYPTFS_TAG_70_DIGEST_SIZE)];
+ if ((s->j % ECRYPTFS_TAG_70_DIGEST_SIZE)
+ == (ECRYPTFS_TAG_70_DIGEST_SIZE - 1)) {
+ rc = crypto_shash_digest(s->hash_desc, (u8 *)s->hash,
+ ECRYPTFS_TAG_70_DIGEST_SIZE,
+ s->tmp_hash);
+ if (rc) {
+ printk(KERN_ERR
+ "%s: Error computing crypto hash; "
+ "rc = [%d]\n", __func__, rc);
+ goto out_release_free_unlock;
+ }
+ memcpy(s->hash, s->tmp_hash,
+ ECRYPTFS_TAG_70_DIGEST_SIZE);
+ }
+ if (s->block_aligned_filename[s->j] == '\0')
+ s->block_aligned_filename[s->j] = ECRYPTFS_NON_NULL;
+ }
+ memcpy(&s->block_aligned_filename[s->num_rand_bytes], filename,
+ filename_size);
+ rc = virt_to_scatterlist(s->block_aligned_filename,
+ s->block_aligned_filename_size, s->src_sg, 2);
+ if (rc < 1) {
+ printk(KERN_ERR "%s: Internal error whilst attempting to "
+ "convert filename memory to scatterlist; rc = [%d]. "
+ "block_aligned_filename_size = [%zd]\n", __func__, rc,
+ s->block_aligned_filename_size);
+ goto out_release_free_unlock;
+ }
+ rc = virt_to_scatterlist(&dest[s->i], s->block_aligned_filename_size,
+ s->dst_sg, 2);
+ if (rc < 1) {
+ printk(KERN_ERR "%s: Internal error whilst attempting to "
+ "convert encrypted filename memory to scatterlist; "
+ "rc = [%d]. block_aligned_filename_size = [%zd]\n",
+ __func__, rc, s->block_aligned_filename_size);
+ goto out_release_free_unlock;
+ }
+ /* The characters in the first block effectively do the job
+ * of the IV here, so we just use 0's for the IV. Note the
+ * constraint that ECRYPTFS_FILENAME_MIN_RANDOM_PREPEND_BYTES
+ * >= ECRYPTFS_MAX_IV_BYTES. */
+ rc = crypto_skcipher_setkey(
+ s->skcipher_tfm,
+ s->auth_tok->token.password.session_key_encryption_key,
+ mount_crypt_stat->global_default_fn_cipher_key_bytes);
+ if (rc < 0) {
+ printk(KERN_ERR "%s: Error setting key for crypto context; "
+ "rc = [%d]. s->auth_tok->token.password.session_key_"
+ "encryption_key = [0x%p]; mount_crypt_stat->"
+ "global_default_fn_cipher_key_bytes = [%zd]\n", __func__,
+ rc,
+ s->auth_tok->token.password.session_key_encryption_key,
+ mount_crypt_stat->global_default_fn_cipher_key_bytes);
+ goto out_release_free_unlock;
+ }
+ skcipher_request_set_crypt(s->skcipher_req, s->src_sg, s->dst_sg,
+ s->block_aligned_filename_size, s->iv);
+ rc = crypto_skcipher_encrypt(s->skcipher_req);
+ if (rc) {
+ printk(KERN_ERR "%s: Error attempting to encrypt filename; "
+ "rc = [%d]\n", __func__, rc);
+ goto out_release_free_unlock;
+ }
+ s->i += s->block_aligned_filename_size;
+ (*packet_size) = s->i;
+ (*remaining_bytes) -= (*packet_size);
+out_release_free_unlock:
+ crypto_free_shash(s->hash_tfm);
+out_free_unlock:
+ kzfree(s->block_aligned_filename);
+out_unlock:
+ mutex_unlock(s->tfm_mutex);
+out:
+ if (auth_tok_key) {
+ up_write(&(auth_tok_key->sem));
+ key_put(auth_tok_key);
+ }
+ skcipher_request_free(s->skcipher_req);
+ kzfree(s->hash_desc);
+ kfree(s);
+ return rc;
+}
+
+struct ecryptfs_parse_tag_70_packet_silly_stack {
+ u8 cipher_code;
+ size_t max_packet_size;
+ size_t packet_size_len;
+ size_t parsed_tag_70_packet_size;
+ size_t block_aligned_filename_size;
+ size_t block_size;
+ size_t i;
+ struct mutex *tfm_mutex;
+ char *decrypted_filename;
+ struct ecryptfs_auth_tok *auth_tok;
+ struct scatterlist src_sg[2];
+ struct scatterlist dst_sg[2];
+ struct crypto_skcipher *skcipher_tfm;
+ struct skcipher_request *skcipher_req;
+ char fnek_sig_hex[ECRYPTFS_SIG_SIZE_HEX + 1];
+ char iv[ECRYPTFS_MAX_IV_BYTES];
+ char cipher_string[ECRYPTFS_MAX_CIPHER_NAME_SIZE + 1];
+};
+
+/**
+ * parse_tag_70_packet - Parse and process FNEK-encrypted passphrase packet
+ * @filename: This function kmalloc's the memory for the filename
+ * @filename_size: This function sets this to the amount of memory
+ * kmalloc'd for the filename
+ * @packet_size: This function sets this to the the number of octets
+ * in the packet parsed
+ * @mount_crypt_stat: The mount-wide cryptographic context
+ * @data: The memory location containing the start of the tag 70
+ * packet
+ * @max_packet_size: The maximum legal size of the packet to be parsed
+ * from @data
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+int
+ecryptfs_parse_tag_70_packet(char **filename, size_t *filename_size,
+ size_t *packet_size,
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
+ char *data, size_t max_packet_size)
+{
+ struct ecryptfs_parse_tag_70_packet_silly_stack *s;
+ struct key *auth_tok_key = NULL;
+ int rc = 0;
+
+ (*packet_size) = 0;
+ (*filename_size) = 0;
+ (*filename) = NULL;
+ s = kzalloc(sizeof(*s), GFP_KERNEL);
+ if (!s)
+ return -ENOMEM;
+
+ if (max_packet_size < ECRYPTFS_TAG_70_MIN_METADATA_SIZE) {
+ printk(KERN_WARNING "%s: max_packet_size is [%zd]; it must be "
+ "at least [%d]\n", __func__, max_packet_size,
+ ECRYPTFS_TAG_70_MIN_METADATA_SIZE);
+ rc = -EINVAL;
+ goto out;
+ }
+ /* Octet 0: Tag 70 identifier
+ * Octets 1-N1: Tag 70 packet size (includes cipher identifier
+ * and block-aligned encrypted filename size)
+ * Octets N1-N2: FNEK sig (ECRYPTFS_SIG_SIZE)
+ * Octet N2-N3: Cipher identifier (1 octet)
+ * Octets N3-N4: Block-aligned encrypted filename
+ * - Consists of a minimum number of random numbers, a \0
+ * separator, and then the filename */
+ if (data[(*packet_size)++] != ECRYPTFS_TAG_70_PACKET_TYPE) {
+ printk(KERN_WARNING "%s: Invalid packet tag [0x%.2x]; must be "
+ "tag [0x%.2x]\n", __func__,
+ data[((*packet_size) - 1)], ECRYPTFS_TAG_70_PACKET_TYPE);
+ rc = -EINVAL;
+ goto out;
+ }
+ rc = ecryptfs_parse_packet_length(&data[(*packet_size)],
+ &s->parsed_tag_70_packet_size,
+ &s->packet_size_len);
+ if (rc) {
+ printk(KERN_WARNING "%s: Error parsing packet length; "
+ "rc = [%d]\n", __func__, rc);
+ goto out;
+ }
+ s->block_aligned_filename_size = (s->parsed_tag_70_packet_size
+ - ECRYPTFS_SIG_SIZE - 1);
+ if ((1 + s->packet_size_len + s->parsed_tag_70_packet_size)
+ > max_packet_size) {
+ printk(KERN_WARNING "%s: max_packet_size is [%zd]; real packet "
+ "size is [%zd]\n", __func__, max_packet_size,
+ (1 + s->packet_size_len + 1
+ + s->block_aligned_filename_size));
+ rc = -EINVAL;
+ goto out;
+ }
+ (*packet_size) += s->packet_size_len;
+ ecryptfs_to_hex(s->fnek_sig_hex, &data[(*packet_size)],
+ ECRYPTFS_SIG_SIZE);
+ s->fnek_sig_hex[ECRYPTFS_SIG_SIZE_HEX] = '\0';
+ (*packet_size) += ECRYPTFS_SIG_SIZE;
+ s->cipher_code = data[(*packet_size)++];
+ rc = ecryptfs_cipher_code_to_string(s->cipher_string, s->cipher_code);
+ if (rc) {
+ printk(KERN_WARNING "%s: Cipher code [%d] is invalid\n",
+ __func__, s->cipher_code);
+ goto out;
+ }
+ rc = ecryptfs_find_auth_tok_for_sig(&auth_tok_key,
+ &s->auth_tok, mount_crypt_stat,
+ s->fnek_sig_hex);
+ if (rc) {
+ printk(KERN_ERR "%s: Error attempting to find auth tok for "
+ "fnek sig [%s]; rc = [%d]\n", __func__, s->fnek_sig_hex,
+ rc);
+ goto out;
+ }
+ rc = ecryptfs_get_tfm_and_mutex_for_cipher_name(&s->skcipher_tfm,
+ &s->tfm_mutex,
+ s->cipher_string);
+ if (unlikely(rc)) {
+ printk(KERN_ERR "Internal error whilst attempting to get "
+ "tfm and mutex for cipher name [%s]; rc = [%d]\n",
+ s->cipher_string, rc);
+ goto out;
+ }
+ mutex_lock(s->tfm_mutex);
+ rc = virt_to_scatterlist(&data[(*packet_size)],
+ s->block_aligned_filename_size, s->src_sg, 2);
+ if (rc < 1) {
+ printk(KERN_ERR "%s: Internal error whilst attempting to "
+ "convert encrypted filename memory to scatterlist; "
+ "rc = [%d]. block_aligned_filename_size = [%zd]\n",
+ __func__, rc, s->block_aligned_filename_size);
+ goto out_unlock;
+ }
+ (*packet_size) += s->block_aligned_filename_size;
+ s->decrypted_filename = kmalloc(s->block_aligned_filename_size,
+ GFP_KERNEL);
+ if (!s->decrypted_filename) {
+ rc = -ENOMEM;
+ goto out_unlock;
+ }
+ rc = virt_to_scatterlist(s->decrypted_filename,
+ s->block_aligned_filename_size, s->dst_sg, 2);
+ if (rc < 1) {
+ printk(KERN_ERR "%s: Internal error whilst attempting to "
+ "convert decrypted filename memory to scatterlist; "
+ "rc = [%d]. block_aligned_filename_size = [%zd]\n",
+ __func__, rc, s->block_aligned_filename_size);
+ goto out_free_unlock;
+ }
+
+ s->skcipher_req = skcipher_request_alloc(s->skcipher_tfm, GFP_KERNEL);
+ if (!s->skcipher_req) {
+ printk(KERN_ERR "%s: Out of kernel memory whilst attempting to "
+ "skcipher_request_alloc for %s\n", __func__,
+ crypto_skcipher_driver_name(s->skcipher_tfm));
+ rc = -ENOMEM;
+ goto out_free_unlock;
+ }
+
+ skcipher_request_set_callback(s->skcipher_req,
+ CRYPTO_TFM_REQ_MAY_SLEEP, NULL, NULL);
+
+ /* The characters in the first block effectively do the job of
+ * the IV here, so we just use 0's for the IV. Note the
+ * constraint that ECRYPTFS_FILENAME_MIN_RANDOM_PREPEND_BYTES
+ * >= ECRYPTFS_MAX_IV_BYTES. */
+ /* TODO: Support other key modules than passphrase for
+ * filename encryption */
+ if (s->auth_tok->token_type != ECRYPTFS_PASSWORD) {
+ rc = -EOPNOTSUPP;
+ printk(KERN_INFO "%s: Filename encryption only supports "
+ "password tokens\n", __func__);
+ goto out_free_unlock;
+ }
+ rc = crypto_skcipher_setkey(
+ s->skcipher_tfm,
+ s->auth_tok->token.password.session_key_encryption_key,
+ mount_crypt_stat->global_default_fn_cipher_key_bytes);
+ if (rc < 0) {
+ printk(KERN_ERR "%s: Error setting key for crypto context; "
+ "rc = [%d]. s->auth_tok->token.password.session_key_"
+ "encryption_key = [0x%p]; mount_crypt_stat->"
+ "global_default_fn_cipher_key_bytes = [%zd]\n", __func__,
+ rc,
+ s->auth_tok->token.password.session_key_encryption_key,
+ mount_crypt_stat->global_default_fn_cipher_key_bytes);
+ goto out_free_unlock;
+ }
+ skcipher_request_set_crypt(s->skcipher_req, s->src_sg, s->dst_sg,
+ s->block_aligned_filename_size, s->iv);
+ rc = crypto_skcipher_decrypt(s->skcipher_req);
+ if (rc) {
+ printk(KERN_ERR "%s: Error attempting to decrypt filename; "
+ "rc = [%d]\n", __func__, rc);
+ goto out_free_unlock;
+ }
+ while (s->decrypted_filename[s->i] != '\0'
+ && s->i < s->block_aligned_filename_size)
+ s->i++;
+ if (s->i == s->block_aligned_filename_size) {
+ printk(KERN_WARNING "%s: Invalid tag 70 packet; could not "
+ "find valid separator between random characters and "
+ "the filename\n", __func__);
+ rc = -EINVAL;
+ goto out_free_unlock;
+ }
+ s->i++;
+ (*filename_size) = (s->block_aligned_filename_size - s->i);
+ if (!((*filename_size) > 0 && (*filename_size < PATH_MAX))) {
+ printk(KERN_WARNING "%s: Filename size is [%zd], which is "
+ "invalid\n", __func__, (*filename_size));
+ rc = -EINVAL;
+ goto out_free_unlock;
+ }
+ (*filename) = kmalloc(((*filename_size) + 1), GFP_KERNEL);
+ if (!(*filename)) {
+ rc = -ENOMEM;
+ goto out_free_unlock;
+ }
+ memcpy((*filename), &s->decrypted_filename[s->i], (*filename_size));
+ (*filename)[(*filename_size)] = '\0';
+out_free_unlock:
+ kfree(s->decrypted_filename);
+out_unlock:
+ mutex_unlock(s->tfm_mutex);
+out:
+ if (rc) {
+ (*packet_size) = 0;
+ (*filename_size) = 0;
+ (*filename) = NULL;
+ }
+ if (auth_tok_key) {
+ up_write(&(auth_tok_key->sem));
+ key_put(auth_tok_key);
+ }
+ skcipher_request_free(s->skcipher_req);
+ kfree(s);
+ return rc;
+}
+
+static int
+ecryptfs_get_auth_tok_sig(char **sig, struct ecryptfs_auth_tok *auth_tok)
+{
+ int rc = 0;
+
+ (*sig) = NULL;
+ switch (auth_tok->token_type) {
+ case ECRYPTFS_PASSWORD:
+ (*sig) = auth_tok->token.password.signature;
+ break;
+ case ECRYPTFS_PRIVATE_KEY:
+ (*sig) = auth_tok->token.private_key.signature;
+ break;
+ default:
+ printk(KERN_ERR "Cannot get sig for auth_tok of type [%d]\n",
+ auth_tok->token_type);
+ rc = -EINVAL;
+ }
+ return rc;
+}
+
+/**
+ * decrypt_pki_encrypted_session_key - Decrypt the session key with the given auth_tok.
+ * @auth_tok: The key authentication token used to decrypt the session key
+ * @crypt_stat: The cryptographic context
+ *
+ * Returns zero on success; non-zero error otherwise.
+ */
+static int
+decrypt_pki_encrypted_session_key(struct ecryptfs_auth_tok *auth_tok,
+ struct ecryptfs_crypt_stat *crypt_stat)
+{
+ u8 cipher_code = 0;
+ struct ecryptfs_msg_ctx *msg_ctx;
+ struct ecryptfs_message *msg = NULL;
+ char *auth_tok_sig;
+ char *payload = NULL;
+ size_t payload_len = 0;
+ int rc;
+
+ rc = ecryptfs_get_auth_tok_sig(&auth_tok_sig, auth_tok);
+ if (rc) {
+ printk(KERN_ERR "Unrecognized auth tok type: [%d]\n",
+ auth_tok->token_type);
+ goto out;
+ }
+ rc = write_tag_64_packet(auth_tok_sig, &(auth_tok->session_key),
+ &payload, &payload_len);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Failed to write tag 64 packet\n");
+ goto out;
+ }
+ rc = ecryptfs_send_message(payload, payload_len, &msg_ctx);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error sending message to "
+ "ecryptfsd: %d\n", rc);
+ goto out;
+ }
+ rc = ecryptfs_wait_for_response(msg_ctx, &msg);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Failed to receive tag 65 packet "
+ "from the user space daemon\n");
+ rc = -EIO;
+ goto out;
+ }
+ rc = parse_tag_65_packet(&(auth_tok->session_key),
+ &cipher_code, msg);
+ if (rc) {
+ printk(KERN_ERR "Failed to parse tag 65 packet; rc = [%d]\n",
+ rc);
+ goto out;
+ }
+ auth_tok->session_key.flags |= ECRYPTFS_CONTAINS_DECRYPTED_KEY;
+ memcpy(crypt_stat->key, auth_tok->session_key.decrypted_key,
+ auth_tok->session_key.decrypted_key_size);
+ crypt_stat->key_size = auth_tok->session_key.decrypted_key_size;
+ rc = ecryptfs_cipher_code_to_string(crypt_stat->cipher, cipher_code);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Cipher code [%d] is invalid\n",
+ cipher_code)
+ goto out;
+ }
+ crypt_stat->flags |= ECRYPTFS_KEY_VALID;
+ if (ecryptfs_verbosity > 0) {
+ ecryptfs_printk(KERN_DEBUG, "Decrypted session key:\n");
+ ecryptfs_dump_hex(crypt_stat->key,
+ crypt_stat->key_size);
+ }
+out:
+ kfree(msg);
+ kfree(payload);
+ return rc;
+}
+
+static void wipe_auth_tok_list(struct list_head *auth_tok_list_head)
+{
+ struct ecryptfs_auth_tok_list_item *auth_tok_list_item;
+ struct ecryptfs_auth_tok_list_item *auth_tok_list_item_tmp;
+
+ list_for_each_entry_safe(auth_tok_list_item, auth_tok_list_item_tmp,
+ auth_tok_list_head, list) {
+ list_del(&auth_tok_list_item->list);
+ kmem_cache_free(ecryptfs_auth_tok_list_item_cache,
+ auth_tok_list_item);
+ }
+}
+
+struct kmem_cache *ecryptfs_auth_tok_list_item_cache;
+
+/**
+ * parse_tag_1_packet
+ * @crypt_stat: The cryptographic context to modify based on packet contents
+ * @data: The raw bytes of the packet.
+ * @auth_tok_list: eCryptfs parses packets into authentication tokens;
+ * a new authentication token will be placed at the
+ * end of this list for this packet.
+ * @new_auth_tok: Pointer to a pointer to memory that this function
+ * allocates; sets the memory address of the pointer to
+ * NULL on error. This object is added to the
+ * auth_tok_list.
+ * @packet_size: This function writes the size of the parsed packet
+ * into this memory location; zero on error.
+ * @max_packet_size: The maximum allowable packet size
+ *
+ * Returns zero on success; non-zero on error.
+ */
+static int
+parse_tag_1_packet(struct ecryptfs_crypt_stat *crypt_stat,
+ unsigned char *data, struct list_head *auth_tok_list,
+ struct ecryptfs_auth_tok **new_auth_tok,
+ size_t *packet_size, size_t max_packet_size)
+{
+ size_t body_size;
+ struct ecryptfs_auth_tok_list_item *auth_tok_list_item;
+ size_t length_size;
+ int rc = 0;
+
+ (*packet_size) = 0;
+ (*new_auth_tok) = NULL;
+ /**
+ * This format is inspired by OpenPGP; see RFC 2440
+ * packet tag 1
+ *
+ * Tag 1 identifier (1 byte)
+ * Max Tag 1 packet size (max 3 bytes)
+ * Version (1 byte)
+ * Key identifier (8 bytes; ECRYPTFS_SIG_SIZE)
+ * Cipher identifier (1 byte)
+ * Encrypted key size (arbitrary)
+ *
+ * 12 bytes minimum packet size
+ */
+ if (unlikely(max_packet_size < 12)) {
+ printk(KERN_ERR "Invalid max packet size; must be >=12\n");
+ rc = -EINVAL;
+ goto out;
+ }
+ if (data[(*packet_size)++] != ECRYPTFS_TAG_1_PACKET_TYPE) {
+ printk(KERN_ERR "Enter w/ first byte != 0x%.2x\n",
+ ECRYPTFS_TAG_1_PACKET_TYPE);
+ rc = -EINVAL;
+ goto out;
+ }
+ /* Released: wipe_auth_tok_list called in ecryptfs_parse_packet_set or
+ * at end of function upon failure */
+ auth_tok_list_item =
+ kmem_cache_zalloc(ecryptfs_auth_tok_list_item_cache,
+ GFP_KERNEL);
+ if (!auth_tok_list_item) {
+ printk(KERN_ERR "Unable to allocate memory\n");
+ rc = -ENOMEM;
+ goto out;
+ }
+ (*new_auth_tok) = &auth_tok_list_item->auth_tok;
+ rc = ecryptfs_parse_packet_length(&data[(*packet_size)], &body_size,
+ &length_size);
+ if (rc) {
+ printk(KERN_WARNING "Error parsing packet length; "
+ "rc = [%d]\n", rc);
+ goto out_free;
+ }
+ if (unlikely(body_size < (ECRYPTFS_SIG_SIZE + 2))) {
+ printk(KERN_WARNING "Invalid body size ([%td])\n", body_size);
+ rc = -EINVAL;
+ goto out_free;
+ }
+ (*packet_size) += length_size;
+ if (unlikely((*packet_size) + body_size > max_packet_size)) {
+ printk(KERN_WARNING "Packet size exceeds max\n");
+ rc = -EINVAL;
+ goto out_free;
+ }
+ if (unlikely(data[(*packet_size)++] != 0x03)) {
+ printk(KERN_WARNING "Unknown version number [%d]\n",
+ data[(*packet_size) - 1]);
+ rc = -EINVAL;
+ goto out_free;
+ }
+ ecryptfs_to_hex((*new_auth_tok)->token.private_key.signature,
+ &data[(*packet_size)], ECRYPTFS_SIG_SIZE);
+ *packet_size += ECRYPTFS_SIG_SIZE;
+ /* This byte is skipped because the kernel does not need to
+ * know which public key encryption algorithm was used */
+ (*packet_size)++;
+ (*new_auth_tok)->session_key.encrypted_key_size =
+ body_size - (ECRYPTFS_SIG_SIZE + 2);
+ if ((*new_auth_tok)->session_key.encrypted_key_size
+ > ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES) {
+ printk(KERN_WARNING "Tag 1 packet contains key larger "
+ "than ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES\n");
+ rc = -EINVAL;
+ goto out;
+ }
+ memcpy((*new_auth_tok)->session_key.encrypted_key,
+ &data[(*packet_size)], (body_size - (ECRYPTFS_SIG_SIZE + 2)));
+ (*packet_size) += (*new_auth_tok)->session_key.encrypted_key_size;
+ (*new_auth_tok)->session_key.flags &=
+ ~ECRYPTFS_CONTAINS_DECRYPTED_KEY;
+ (*new_auth_tok)->session_key.flags |=
+ ECRYPTFS_CONTAINS_ENCRYPTED_KEY;
+ (*new_auth_tok)->token_type = ECRYPTFS_PRIVATE_KEY;
+ (*new_auth_tok)->flags = 0;
+ (*new_auth_tok)->session_key.flags &=
+ ~(ECRYPTFS_USERSPACE_SHOULD_TRY_TO_DECRYPT);
+ (*new_auth_tok)->session_key.flags &=
+ ~(ECRYPTFS_USERSPACE_SHOULD_TRY_TO_ENCRYPT);
+ list_add(&auth_tok_list_item->list, auth_tok_list);
+ goto out;
+out_free:
+ (*new_auth_tok) = NULL;
+ memset(auth_tok_list_item, 0,
+ sizeof(struct ecryptfs_auth_tok_list_item));
+ kmem_cache_free(ecryptfs_auth_tok_list_item_cache,
+ auth_tok_list_item);
+out:
+ if (rc)
+ (*packet_size) = 0;
+ return rc;
+}
+
+/**
+ * parse_tag_3_packet
+ * @crypt_stat: The cryptographic context to modify based on packet
+ * contents.
+ * @data: The raw bytes of the packet.
+ * @auth_tok_list: eCryptfs parses packets into authentication tokens;
+ * a new authentication token will be placed at the end
+ * of this list for this packet.
+ * @new_auth_tok: Pointer to a pointer to memory that this function
+ * allocates; sets the memory address of the pointer to
+ * NULL on error. This object is added to the
+ * auth_tok_list.
+ * @packet_size: This function writes the size of the parsed packet
+ * into this memory location; zero on error.
+ * @max_packet_size: maximum number of bytes to parse
+ *
+ * Returns zero on success; non-zero on error.
+ */
+static int
+parse_tag_3_packet(struct ecryptfs_crypt_stat *crypt_stat,
+ unsigned char *data, struct list_head *auth_tok_list,
+ struct ecryptfs_auth_tok **new_auth_tok,
+ size_t *packet_size, size_t max_packet_size)
+{
+ size_t body_size;
+ struct ecryptfs_auth_tok_list_item *auth_tok_list_item;
+ size_t length_size;
+ int rc = 0;
+
+ (*packet_size) = 0;
+ (*new_auth_tok) = NULL;
+ /**
+ *This format is inspired by OpenPGP; see RFC 2440
+ * packet tag 3
+ *
+ * Tag 3 identifier (1 byte)
+ * Max Tag 3 packet size (max 3 bytes)
+ * Version (1 byte)
+ * Cipher code (1 byte)
+ * S2K specifier (1 byte)
+ * Hash identifier (1 byte)
+ * Salt (ECRYPTFS_SALT_SIZE)
+ * Hash iterations (1 byte)
+ * Encrypted key (arbitrary)
+ *
+ * (ECRYPTFS_SALT_SIZE + 7) minimum packet size
+ */
+ if (max_packet_size < (ECRYPTFS_SALT_SIZE + 7)) {
+ printk(KERN_ERR "Max packet size too large\n");
+ rc = -EINVAL;
+ goto out;
+ }
+ if (data[(*packet_size)++] != ECRYPTFS_TAG_3_PACKET_TYPE) {
+ printk(KERN_ERR "First byte != 0x%.2x; invalid packet\n",
+ ECRYPTFS_TAG_3_PACKET_TYPE);
+ rc = -EINVAL;
+ goto out;
+ }
+ /* Released: wipe_auth_tok_list called in ecryptfs_parse_packet_set or
+ * at end of function upon failure */
+ auth_tok_list_item =
+ kmem_cache_zalloc(ecryptfs_auth_tok_list_item_cache, GFP_KERNEL);
+ if (!auth_tok_list_item) {
+ printk(KERN_ERR "Unable to allocate memory\n");
+ rc = -ENOMEM;
+ goto out;
+ }
+ (*new_auth_tok) = &auth_tok_list_item->auth_tok;
+ rc = ecryptfs_parse_packet_length(&data[(*packet_size)], &body_size,
+ &length_size);
+ if (rc) {
+ printk(KERN_WARNING "Error parsing packet length; rc = [%d]\n",
+ rc);
+ goto out_free;
+ }
+ if (unlikely(body_size < (ECRYPTFS_SALT_SIZE + 5))) {
+ printk(KERN_WARNING "Invalid body size ([%td])\n", body_size);
+ rc = -EINVAL;
+ goto out_free;
+ }
+ (*packet_size) += length_size;
+ if (unlikely((*packet_size) + body_size > max_packet_size)) {
+ printk(KERN_ERR "Packet size exceeds max\n");
+ rc = -EINVAL;
+ goto out_free;
+ }
+ (*new_auth_tok)->session_key.encrypted_key_size =
+ (body_size - (ECRYPTFS_SALT_SIZE + 5));
+ if ((*new_auth_tok)->session_key.encrypted_key_size
+ > ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES) {
+ printk(KERN_WARNING "Tag 3 packet contains key larger "
+ "than ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES\n");
+ rc = -EINVAL;
+ goto out_free;
+ }
+ if (unlikely(data[(*packet_size)++] != 0x04)) {
+ printk(KERN_WARNING "Unknown version number [%d]\n",
+ data[(*packet_size) - 1]);
+ rc = -EINVAL;
+ goto out_free;
+ }
+ rc = ecryptfs_cipher_code_to_string(crypt_stat->cipher,
+ (u16)data[(*packet_size)]);
+ if (rc)
+ goto out_free;
+ /* A little extra work to differentiate among the AES key
+ * sizes; see RFC2440 */
+ switch(data[(*packet_size)++]) {
+ case RFC2440_CIPHER_AES_192:
+ crypt_stat->key_size = 24;
+ break;
+ default:
+ crypt_stat->key_size =
+ (*new_auth_tok)->session_key.encrypted_key_size;
+ }
+ rc = ecryptfs_init_crypt_ctx(crypt_stat);
+ if (rc)
+ goto out_free;
+ if (unlikely(data[(*packet_size)++] != 0x03)) {
+ printk(KERN_WARNING "Only S2K ID 3 is currently supported\n");
+ rc = -ENOSYS;
+ goto out_free;
+ }
+ /* TODO: finish the hash mapping */
+ switch (data[(*packet_size)++]) {
+ case 0x01: /* See RFC2440 for these numbers and their mappings */
+ /* Choose MD5 */
+ memcpy((*new_auth_tok)->token.password.salt,
+ &data[(*packet_size)], ECRYPTFS_SALT_SIZE);
+ (*packet_size) += ECRYPTFS_SALT_SIZE;
+ /* This conversion was taken straight from RFC2440 */
+ (*new_auth_tok)->token.password.hash_iterations =
+ ((u32) 16 + (data[(*packet_size)] & 15))
+ << ((data[(*packet_size)] >> 4) + 6);
+ (*packet_size)++;
+ /* Friendly reminder:
+ * (*new_auth_tok)->session_key.encrypted_key_size =
+ * (body_size - (ECRYPTFS_SALT_SIZE + 5)); */
+ memcpy((*new_auth_tok)->session_key.encrypted_key,
+ &data[(*packet_size)],
+ (*new_auth_tok)->session_key.encrypted_key_size);
+ (*packet_size) +=
+ (*new_auth_tok)->session_key.encrypted_key_size;
+ (*new_auth_tok)->session_key.flags &=
+ ~ECRYPTFS_CONTAINS_DECRYPTED_KEY;
+ (*new_auth_tok)->session_key.flags |=
+ ECRYPTFS_CONTAINS_ENCRYPTED_KEY;
+ (*new_auth_tok)->token.password.hash_algo = 0x01; /* MD5 */
+ break;
+ default:
+ ecryptfs_printk(KERN_ERR, "Unsupported hash algorithm: "
+ "[%d]\n", data[(*packet_size) - 1]);
+ rc = -ENOSYS;
+ goto out_free;
+ }
+ (*new_auth_tok)->token_type = ECRYPTFS_PASSWORD;
+ /* TODO: Parametarize; we might actually want userspace to
+ * decrypt the session key. */
+ (*new_auth_tok)->session_key.flags &=
+ ~(ECRYPTFS_USERSPACE_SHOULD_TRY_TO_DECRYPT);
+ (*new_auth_tok)->session_key.flags &=
+ ~(ECRYPTFS_USERSPACE_SHOULD_TRY_TO_ENCRYPT);
+ list_add(&auth_tok_list_item->list, auth_tok_list);
+ goto out;
+out_free:
+ (*new_auth_tok) = NULL;
+ memset(auth_tok_list_item, 0,
+ sizeof(struct ecryptfs_auth_tok_list_item));
+ kmem_cache_free(ecryptfs_auth_tok_list_item_cache,
+ auth_tok_list_item);
+out:
+ if (rc)
+ (*packet_size) = 0;
+ return rc;
+}
+
+/**
+ * parse_tag_11_packet
+ * @data: The raw bytes of the packet
+ * @contents: This function writes the data contents of the literal
+ * packet into this memory location
+ * @max_contents_bytes: The maximum number of bytes that this function
+ * is allowed to write into contents
+ * @tag_11_contents_size: This function writes the size of the parsed
+ * contents into this memory location; zero on
+ * error
+ * @packet_size: This function writes the size of the parsed packet
+ * into this memory location; zero on error
+ * @max_packet_size: maximum number of bytes to parse
+ *
+ * Returns zero on success; non-zero on error.
+ */
+static int
+parse_tag_11_packet(unsigned char *data, unsigned char *contents,
+ size_t max_contents_bytes, size_t *tag_11_contents_size,
+ size_t *packet_size, size_t max_packet_size)
+{
+ size_t body_size;
+ size_t length_size;
+ int rc = 0;
+
+ (*packet_size) = 0;
+ (*tag_11_contents_size) = 0;
+ /* This format is inspired by OpenPGP; see RFC 2440
+ * packet tag 11
+ *
+ * Tag 11 identifier (1 byte)
+ * Max Tag 11 packet size (max 3 bytes)
+ * Binary format specifier (1 byte)
+ * Filename length (1 byte)
+ * Filename ("_CONSOLE") (8 bytes)
+ * Modification date (4 bytes)
+ * Literal data (arbitrary)
+ *
+ * We need at least 16 bytes of data for the packet to even be
+ * valid.
+ */
+ if (max_packet_size < 16) {
+ printk(KERN_ERR "Maximum packet size too small\n");
+ rc = -EINVAL;
+ goto out;
+ }
+ if (data[(*packet_size)++] != ECRYPTFS_TAG_11_PACKET_TYPE) {
+ printk(KERN_WARNING "Invalid tag 11 packet format\n");
+ rc = -EINVAL;
+ goto out;
+ }
+ rc = ecryptfs_parse_packet_length(&data[(*packet_size)], &body_size,
+ &length_size);
+ if (rc) {
+ printk(KERN_WARNING "Invalid tag 11 packet format\n");
+ goto out;
+ }
+ if (body_size < 14) {
+ printk(KERN_WARNING "Invalid body size ([%td])\n", body_size);
+ rc = -EINVAL;
+ goto out;
+ }
+ (*packet_size) += length_size;
+ (*tag_11_contents_size) = (body_size - 14);
+ if (unlikely((*packet_size) + body_size + 1 > max_packet_size)) {
+ printk(KERN_ERR "Packet size exceeds max\n");
+ rc = -EINVAL;
+ goto out;
+ }
+ if (unlikely((*tag_11_contents_size) > max_contents_bytes)) {
+ printk(KERN_ERR "Literal data section in tag 11 packet exceeds "
+ "expected size\n");
+ rc = -EINVAL;
+ goto out;
+ }
+ if (data[(*packet_size)++] != 0x62) {
+ printk(KERN_WARNING "Unrecognizable packet\n");
+ rc = -EINVAL;
+ goto out;
+ }
+ if (data[(*packet_size)++] != 0x08) {
+ printk(KERN_WARNING "Unrecognizable packet\n");
+ rc = -EINVAL;
+ goto out;
+ }
+ (*packet_size) += 12; /* Ignore filename and modification date */
+ memcpy(contents, &data[(*packet_size)], (*tag_11_contents_size));
+ (*packet_size) += (*tag_11_contents_size);
+out:
+ if (rc) {
+ (*packet_size) = 0;
+ (*tag_11_contents_size) = 0;
+ }
+ return rc;
+}
+
+int ecryptfs_keyring_auth_tok_for_sig(struct key **auth_tok_key,
+ struct ecryptfs_auth_tok **auth_tok,
+ char *sig)
+{
+ int rc = 0;
+
+ (*auth_tok_key) = request_key(&key_type_user, sig, NULL);
+ if (!(*auth_tok_key) || IS_ERR(*auth_tok_key)) {
+ (*auth_tok_key) = ecryptfs_get_encrypted_key(sig);
+ if (!(*auth_tok_key) || IS_ERR(*auth_tok_key)) {
+ printk(KERN_ERR "Could not find key with description: [%s]\n",
+ sig);
+ rc = process_request_key_err(PTR_ERR(*auth_tok_key));
+ (*auth_tok_key) = NULL;
+ goto out;
+ }
+ }
+ down_write(&(*auth_tok_key)->sem);
+ rc = ecryptfs_verify_auth_tok_from_key(*auth_tok_key, auth_tok);
+ if (rc) {
+ up_write(&(*auth_tok_key)->sem);
+ key_put(*auth_tok_key);
+ (*auth_tok_key) = NULL;
+ goto out;
+ }
+out:
+ return rc;
+}
+
+/**
+ * decrypt_passphrase_encrypted_session_key - Decrypt the session key with the given auth_tok.
+ * @auth_tok: The passphrase authentication token to use to encrypt the FEK
+ * @crypt_stat: The cryptographic context
+ *
+ * Returns zero on success; non-zero error otherwise
+ */
+static int
+decrypt_passphrase_encrypted_session_key(struct ecryptfs_auth_tok *auth_tok,
+ struct ecryptfs_crypt_stat *crypt_stat)
+{
+ struct scatterlist dst_sg[2];
+ struct scatterlist src_sg[2];
+ struct mutex *tfm_mutex;
+ struct crypto_skcipher *tfm;
+ struct skcipher_request *req = NULL;
+ int rc = 0;
+
+ if (unlikely(ecryptfs_verbosity > 0)) {
+ ecryptfs_printk(
+ KERN_DEBUG, "Session key encryption key (size [%d]):\n",
+ auth_tok->token.password.session_key_encryption_key_bytes);
+ ecryptfs_dump_hex(
+ auth_tok->token.password.session_key_encryption_key,
+ auth_tok->token.password.session_key_encryption_key_bytes);
+ }
+ rc = ecryptfs_get_tfm_and_mutex_for_cipher_name(&tfm, &tfm_mutex,
+ crypt_stat->cipher);
+ if (unlikely(rc)) {
+ printk(KERN_ERR "Internal error whilst attempting to get "
+ "tfm and mutex for cipher name [%s]; rc = [%d]\n",
+ crypt_stat->cipher, rc);
+ goto out;
+ }
+ rc = virt_to_scatterlist(auth_tok->session_key.encrypted_key,
+ auth_tok->session_key.encrypted_key_size,
+ src_sg, 2);
+ if (rc < 1 || rc > 2) {
+ printk(KERN_ERR "Internal error whilst attempting to convert "
+ "auth_tok->session_key.encrypted_key to scatterlist; "
+ "expected rc = 1; got rc = [%d]. "
+ "auth_tok->session_key.encrypted_key_size = [%d]\n", rc,
+ auth_tok->session_key.encrypted_key_size);
+ goto out;
+ }
+ auth_tok->session_key.decrypted_key_size =
+ auth_tok->session_key.encrypted_key_size;
+ rc = virt_to_scatterlist(auth_tok->session_key.decrypted_key,
+ auth_tok->session_key.decrypted_key_size,
+ dst_sg, 2);
+ if (rc < 1 || rc > 2) {
+ printk(KERN_ERR "Internal error whilst attempting to convert "
+ "auth_tok->session_key.decrypted_key to scatterlist; "
+ "expected rc = 1; got rc = [%d]\n", rc);
+ goto out;
+ }
+ mutex_lock(tfm_mutex);
+ req = skcipher_request_alloc(tfm, GFP_KERNEL);
+ if (!req) {
+ mutex_unlock(tfm_mutex);
+ printk(KERN_ERR "%s: Out of kernel memory whilst attempting to "
+ "skcipher_request_alloc for %s\n", __func__,
+ crypto_skcipher_driver_name(tfm));
+ rc = -ENOMEM;
+ goto out;
+ }
+
+ skcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_SLEEP,
+ NULL, NULL);
+ rc = crypto_skcipher_setkey(
+ tfm, auth_tok->token.password.session_key_encryption_key,
+ crypt_stat->key_size);
+ if (unlikely(rc < 0)) {
+ mutex_unlock(tfm_mutex);
+ printk(KERN_ERR "Error setting key for crypto context\n");
+ rc = -EINVAL;
+ goto out;
+ }
+ skcipher_request_set_crypt(req, src_sg, dst_sg,
+ auth_tok->session_key.encrypted_key_size,
+ NULL);
+ rc = crypto_skcipher_decrypt(req);
+ mutex_unlock(tfm_mutex);
+ if (unlikely(rc)) {
+ printk(KERN_ERR "Error decrypting; rc = [%d]\n", rc);
+ goto out;
+ }
+ auth_tok->session_key.flags |= ECRYPTFS_CONTAINS_DECRYPTED_KEY;
+ memcpy(crypt_stat->key, auth_tok->session_key.decrypted_key,
+ auth_tok->session_key.decrypted_key_size);
+ crypt_stat->flags |= ECRYPTFS_KEY_VALID;
+ if (unlikely(ecryptfs_verbosity > 0)) {
+ ecryptfs_printk(KERN_DEBUG, "FEK of size [%zd]:\n",
+ crypt_stat->key_size);
+ ecryptfs_dump_hex(crypt_stat->key,
+ crypt_stat->key_size);
+ }
+out:
+ skcipher_request_free(req);
+ return rc;
+}
+
+/**
+ * ecryptfs_parse_packet_set
+ * @crypt_stat: The cryptographic context
+ * @src: Virtual address of region of memory containing the packets
+ * @ecryptfs_dentry: The eCryptfs dentry associated with the packet set
+ *
+ * Get crypt_stat to have the file's session key if the requisite key
+ * is available to decrypt the session key.
+ *
+ * Returns Zero if a valid authentication token was retrieved and
+ * processed; negative value for file not encrypted or for error
+ * conditions.
+ */
+int ecryptfs_parse_packet_set(struct ecryptfs_crypt_stat *crypt_stat,
+ unsigned char *src,
+ struct dentry *ecryptfs_dentry)
+{
+ size_t i = 0;
+ size_t found_auth_tok;
+ size_t next_packet_is_auth_tok_packet;
+ struct list_head auth_tok_list;
+ struct ecryptfs_auth_tok *matching_auth_tok;
+ struct ecryptfs_auth_tok *candidate_auth_tok;
+ char *candidate_auth_tok_sig;
+ size_t packet_size;
+ struct ecryptfs_auth_tok *new_auth_tok;
+ unsigned char sig_tmp_space[ECRYPTFS_SIG_SIZE];
+ struct ecryptfs_auth_tok_list_item *auth_tok_list_item;
+ size_t tag_11_contents_size;
+ size_t tag_11_packet_size;
+ struct key *auth_tok_key = NULL;
+ int rc = 0;
+
+ INIT_LIST_HEAD(&auth_tok_list);
+ /* Parse the header to find as many packets as we can; these will be
+ * added the our &auth_tok_list */
+ next_packet_is_auth_tok_packet = 1;
+ while (next_packet_is_auth_tok_packet) {
+ size_t max_packet_size = ((PAGE_SIZE - 8) - i);
+
+ switch (src[i]) {
+ case ECRYPTFS_TAG_3_PACKET_TYPE:
+ rc = parse_tag_3_packet(crypt_stat,
+ (unsigned char *)&src[i],
+ &auth_tok_list, &new_auth_tok,
+ &packet_size, max_packet_size);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error parsing "
+ "tag 3 packet\n");
+ rc = -EIO;
+ goto out_wipe_list;
+ }
+ i += packet_size;
+ rc = parse_tag_11_packet((unsigned char *)&src[i],
+ sig_tmp_space,
+ ECRYPTFS_SIG_SIZE,
+ &tag_11_contents_size,
+ &tag_11_packet_size,
+ max_packet_size);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "No valid "
+ "(ecryptfs-specific) literal "
+ "packet containing "
+ "authentication token "
+ "signature found after "
+ "tag 3 packet\n");
+ rc = -EIO;
+ goto out_wipe_list;
+ }
+ i += tag_11_packet_size;
+ if (ECRYPTFS_SIG_SIZE != tag_11_contents_size) {
+ ecryptfs_printk(KERN_ERR, "Expected "
+ "signature of size [%d]; "
+ "read size [%zd]\n",
+ ECRYPTFS_SIG_SIZE,
+ tag_11_contents_size);
+ rc = -EIO;
+ goto out_wipe_list;
+ }
+ ecryptfs_to_hex(new_auth_tok->token.password.signature,
+ sig_tmp_space, tag_11_contents_size);
+ new_auth_tok->token.password.signature[
+ ECRYPTFS_PASSWORD_SIG_SIZE] = '\0';
+ crypt_stat->flags |= ECRYPTFS_ENCRYPTED;
+ break;
+ case ECRYPTFS_TAG_1_PACKET_TYPE:
+ rc = parse_tag_1_packet(crypt_stat,
+ (unsigned char *)&src[i],
+ &auth_tok_list, &new_auth_tok,
+ &packet_size, max_packet_size);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error parsing "
+ "tag 1 packet\n");
+ rc = -EIO;
+ goto out_wipe_list;
+ }
+ i += packet_size;
+ crypt_stat->flags |= ECRYPTFS_ENCRYPTED;
+ break;
+ case ECRYPTFS_TAG_11_PACKET_TYPE:
+ ecryptfs_printk(KERN_WARNING, "Invalid packet set "
+ "(Tag 11 not allowed by itself)\n");
+ rc = -EIO;
+ goto out_wipe_list;
+ default:
+ ecryptfs_printk(KERN_DEBUG, "No packet at offset [%zd] "
+ "of the file header; hex value of "
+ "character is [0x%.2x]\n", i, src[i]);
+ next_packet_is_auth_tok_packet = 0;
+ }
+ }
+ if (list_empty(&auth_tok_list)) {
+ printk(KERN_ERR "The lower file appears to be a non-encrypted "
+ "eCryptfs file; this is not supported in this version "
+ "of the eCryptfs kernel module\n");
+ rc = -EINVAL;
+ goto out;
+ }
+ /* auth_tok_list contains the set of authentication tokens
+ * parsed from the metadata. We need to find a matching
+ * authentication token that has the secret component(s)
+ * necessary to decrypt the EFEK in the auth_tok parsed from
+ * the metadata. There may be several potential matches, but
+ * just one will be sufficient to decrypt to get the FEK. */
+find_next_matching_auth_tok:
+ found_auth_tok = 0;
+ list_for_each_entry(auth_tok_list_item, &auth_tok_list, list) {
+ candidate_auth_tok = &auth_tok_list_item->auth_tok;
+ if (unlikely(ecryptfs_verbosity > 0)) {
+ ecryptfs_printk(KERN_DEBUG,
+ "Considering candidate auth tok:\n");
+ ecryptfs_dump_auth_tok(candidate_auth_tok);
+ }
+ rc = ecryptfs_get_auth_tok_sig(&candidate_auth_tok_sig,
+ candidate_auth_tok);
+ if (rc) {
+ printk(KERN_ERR
+ "Unrecognized candidate auth tok type: [%d]\n",
+ candidate_auth_tok->token_type);
+ rc = -EINVAL;
+ goto out_wipe_list;
+ }
+ rc = ecryptfs_find_auth_tok_for_sig(&auth_tok_key,
+ &matching_auth_tok,
+ crypt_stat->mount_crypt_stat,
+ candidate_auth_tok_sig);
+ if (!rc) {
+ found_auth_tok = 1;
+ goto found_matching_auth_tok;
+ }
+ }
+ if (!found_auth_tok) {
+ ecryptfs_printk(KERN_ERR, "Could not find a usable "
+ "authentication token\n");
+ rc = -EIO;
+ goto out_wipe_list;
+ }
+found_matching_auth_tok:
+ if (candidate_auth_tok->token_type == ECRYPTFS_PRIVATE_KEY) {
+ memcpy(&(candidate_auth_tok->token.private_key),
+ &(matching_auth_tok->token.private_key),
+ sizeof(struct ecryptfs_private_key));
+ up_write(&(auth_tok_key->sem));
+ key_put(auth_tok_key);
+ rc = decrypt_pki_encrypted_session_key(candidate_auth_tok,
+ crypt_stat);
+ } else if (candidate_auth_tok->token_type == ECRYPTFS_PASSWORD) {
+ memcpy(&(candidate_auth_tok->token.password),
+ &(matching_auth_tok->token.password),
+ sizeof(struct ecryptfs_password));
+ up_write(&(auth_tok_key->sem));
+ key_put(auth_tok_key);
+ rc = decrypt_passphrase_encrypted_session_key(
+ candidate_auth_tok, crypt_stat);
+ } else {
+ up_write(&(auth_tok_key->sem));
+ key_put(auth_tok_key);
+ rc = -EINVAL;
+ }
+ if (rc) {
+ struct ecryptfs_auth_tok_list_item *auth_tok_list_item_tmp;
+
+ ecryptfs_printk(KERN_WARNING, "Error decrypting the "
+ "session key for authentication token with sig "
+ "[%.*s]; rc = [%d]. Removing auth tok "
+ "candidate from the list and searching for "
+ "the next match.\n", ECRYPTFS_SIG_SIZE_HEX,
+ candidate_auth_tok_sig, rc);
+ list_for_each_entry_safe(auth_tok_list_item,
+ auth_tok_list_item_tmp,
+ &auth_tok_list, list) {
+ if (candidate_auth_tok
+ == &auth_tok_list_item->auth_tok) {
+ list_del(&auth_tok_list_item->list);
+ kmem_cache_free(
+ ecryptfs_auth_tok_list_item_cache,
+ auth_tok_list_item);
+ goto find_next_matching_auth_tok;
+ }
+ }
+ BUG();
+ }
+ rc = ecryptfs_compute_root_iv(crypt_stat);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error computing "
+ "the root IV\n");
+ goto out_wipe_list;
+ }
+ rc = ecryptfs_init_crypt_ctx(crypt_stat);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error initializing crypto "
+ "context for cipher [%s]; rc = [%d]\n",
+ crypt_stat->cipher, rc);
+ }
+out_wipe_list:
+ wipe_auth_tok_list(&auth_tok_list);
+out:
+ return rc;
+}
+
+static int
+pki_encrypt_session_key(struct key *auth_tok_key,
+ struct ecryptfs_auth_tok *auth_tok,
+ struct ecryptfs_crypt_stat *crypt_stat,
+ struct ecryptfs_key_record *key_rec)
+{
+ struct ecryptfs_msg_ctx *msg_ctx = NULL;
+ char *payload = NULL;
+ size_t payload_len = 0;
+ struct ecryptfs_message *msg;
+ int rc;
+
+ rc = write_tag_66_packet(auth_tok->token.private_key.signature,
+ ecryptfs_code_for_cipher_string(
+ crypt_stat->cipher,
+ crypt_stat->key_size),
+ crypt_stat, &payload, &payload_len);
+ up_write(&(auth_tok_key->sem));
+ key_put(auth_tok_key);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error generating tag 66 packet\n");
+ goto out;
+ }
+ rc = ecryptfs_send_message(payload, payload_len, &msg_ctx);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error sending message to "
+ "ecryptfsd: %d\n", rc);
+ goto out;
+ }
+ rc = ecryptfs_wait_for_response(msg_ctx, &msg);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Failed to receive tag 67 packet "
+ "from the user space daemon\n");
+ rc = -EIO;
+ goto out;
+ }
+ rc = parse_tag_67_packet(key_rec, msg);
+ if (rc)
+ ecryptfs_printk(KERN_ERR, "Error parsing tag 67 packet\n");
+ kfree(msg);
+out:
+ kfree(payload);
+ return rc;
+}
+/**
+ * write_tag_1_packet - Write an RFC2440-compatible tag 1 (public key) packet
+ * @dest: Buffer into which to write the packet
+ * @remaining_bytes: Maximum number of bytes that can be writtn
+ * @auth_tok_key: The authentication token key to unlock and put when done with
+ * @auth_tok
+ * @auth_tok: The authentication token used for generating the tag 1 packet
+ * @crypt_stat: The cryptographic context
+ * @key_rec: The key record struct for the tag 1 packet
+ * @packet_size: This function will write the number of bytes that end
+ * up constituting the packet; set to zero on error
+ *
+ * Returns zero on success; non-zero on error.
+ */
+static int
+write_tag_1_packet(char *dest, size_t *remaining_bytes,
+ struct key *auth_tok_key, struct ecryptfs_auth_tok *auth_tok,
+ struct ecryptfs_crypt_stat *crypt_stat,
+ struct ecryptfs_key_record *key_rec, size_t *packet_size)
+{
+ size_t i;
+ size_t encrypted_session_key_valid = 0;
+ size_t packet_size_length;
+ size_t max_packet_size;
+ int rc = 0;
+
+ (*packet_size) = 0;
+ ecryptfs_from_hex(key_rec->sig, auth_tok->token.private_key.signature,
+ ECRYPTFS_SIG_SIZE);
+ encrypted_session_key_valid = 0;
+ for (i = 0; i < crypt_stat->key_size; i++)
+ encrypted_session_key_valid |=
+ auth_tok->session_key.encrypted_key[i];
+ if (encrypted_session_key_valid) {
+ memcpy(key_rec->enc_key,
+ auth_tok->session_key.encrypted_key,
+ auth_tok->session_key.encrypted_key_size);
+ up_write(&(auth_tok_key->sem));
+ key_put(auth_tok_key);
+ goto encrypted_session_key_set;
+ }
+ if (auth_tok->session_key.encrypted_key_size == 0)
+ auth_tok->session_key.encrypted_key_size =
+ auth_tok->token.private_key.key_size;
+ rc = pki_encrypt_session_key(auth_tok_key, auth_tok, crypt_stat,
+ key_rec);
+ if (rc) {
+ printk(KERN_ERR "Failed to encrypt session key via a key "
+ "module; rc = [%d]\n", rc);
+ goto out;
+ }
+ if (ecryptfs_verbosity > 0) {
+ ecryptfs_printk(KERN_DEBUG, "Encrypted key:\n");
+ ecryptfs_dump_hex(key_rec->enc_key, key_rec->enc_key_size);
+ }
+encrypted_session_key_set:
+ /* This format is inspired by OpenPGP; see RFC 2440
+ * packet tag 1 */
+ max_packet_size = (1 /* Tag 1 identifier */
+ + 3 /* Max Tag 1 packet size */
+ + 1 /* Version */
+ + ECRYPTFS_SIG_SIZE /* Key identifier */
+ + 1 /* Cipher identifier */
+ + key_rec->enc_key_size); /* Encrypted key size */
+ if (max_packet_size > (*remaining_bytes)) {
+ printk(KERN_ERR "Packet length larger than maximum allowable; "
+ "need up to [%td] bytes, but there are only [%td] "
+ "available\n", max_packet_size, (*remaining_bytes));
+ rc = -EINVAL;
+ goto out;
+ }
+ dest[(*packet_size)++] = ECRYPTFS_TAG_1_PACKET_TYPE;
+ rc = ecryptfs_write_packet_length(&dest[(*packet_size)],
+ (max_packet_size - 4),
+ &packet_size_length);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error generating tag 1 packet "
+ "header; cannot generate packet length\n");
+ goto out;
+ }
+ (*packet_size) += packet_size_length;
+ dest[(*packet_size)++] = 0x03; /* version 3 */
+ memcpy(&dest[(*packet_size)], key_rec->sig, ECRYPTFS_SIG_SIZE);
+ (*packet_size) += ECRYPTFS_SIG_SIZE;
+ dest[(*packet_size)++] = RFC2440_CIPHER_RSA;
+ memcpy(&dest[(*packet_size)], key_rec->enc_key,
+ key_rec->enc_key_size);
+ (*packet_size) += key_rec->enc_key_size;
+out:
+ if (rc)
+ (*packet_size) = 0;
+ else
+ (*remaining_bytes) -= (*packet_size);
+ return rc;
+}
+
+/**
+ * write_tag_11_packet
+ * @dest: Target into which Tag 11 packet is to be written
+ * @remaining_bytes: Maximum packet length
+ * @contents: Byte array of contents to copy in
+ * @contents_length: Number of bytes in contents
+ * @packet_length: Length of the Tag 11 packet written; zero on error
+ *
+ * Returns zero on success; non-zero on error.
+ */
+static int
+write_tag_11_packet(char *dest, size_t *remaining_bytes, char *contents,
+ size_t contents_length, size_t *packet_length)
+{
+ size_t packet_size_length;
+ size_t max_packet_size;
+ int rc = 0;
+
+ (*packet_length) = 0;
+ /* This format is inspired by OpenPGP; see RFC 2440
+ * packet tag 11 */
+ max_packet_size = (1 /* Tag 11 identifier */
+ + 3 /* Max Tag 11 packet size */
+ + 1 /* Binary format specifier */
+ + 1 /* Filename length */
+ + 8 /* Filename ("_CONSOLE") */
+ + 4 /* Modification date */
+ + contents_length); /* Literal data */
+ if (max_packet_size > (*remaining_bytes)) {
+ printk(KERN_ERR "Packet length larger than maximum allowable; "
+ "need up to [%td] bytes, but there are only [%td] "
+ "available\n", max_packet_size, (*remaining_bytes));
+ rc = -EINVAL;
+ goto out;
+ }
+ dest[(*packet_length)++] = ECRYPTFS_TAG_11_PACKET_TYPE;
+ rc = ecryptfs_write_packet_length(&dest[(*packet_length)],
+ (max_packet_size - 4),
+ &packet_size_length);
+ if (rc) {
+ printk(KERN_ERR "Error generating tag 11 packet header; cannot "
+ "generate packet length. rc = [%d]\n", rc);
+ goto out;
+ }
+ (*packet_length) += packet_size_length;
+ dest[(*packet_length)++] = 0x62; /* binary data format specifier */
+ dest[(*packet_length)++] = 8;
+ memcpy(&dest[(*packet_length)], "_CONSOLE", 8);
+ (*packet_length) += 8;
+ memset(&dest[(*packet_length)], 0x00, 4);
+ (*packet_length) += 4;
+ memcpy(&dest[(*packet_length)], contents, contents_length);
+ (*packet_length) += contents_length;
+ out:
+ if (rc)
+ (*packet_length) = 0;
+ else
+ (*remaining_bytes) -= (*packet_length);
+ return rc;
+}
+
+/**
+ * write_tag_3_packet
+ * @dest: Buffer into which to write the packet
+ * @remaining_bytes: Maximum number of bytes that can be written
+ * @auth_tok: Authentication token
+ * @crypt_stat: The cryptographic context
+ * @key_rec: encrypted key
+ * @packet_size: This function will write the number of bytes that end
+ * up constituting the packet; set to zero on error
+ *
+ * Returns zero on success; non-zero on error.
+ */
+static int
+write_tag_3_packet(char *dest, size_t *remaining_bytes,
+ struct ecryptfs_auth_tok *auth_tok,
+ struct ecryptfs_crypt_stat *crypt_stat,
+ struct ecryptfs_key_record *key_rec, size_t *packet_size)
+{
+ size_t i;
+ size_t encrypted_session_key_valid = 0;
+ char session_key_encryption_key[ECRYPTFS_MAX_KEY_BYTES];
+ struct scatterlist dst_sg[2];
+ struct scatterlist src_sg[2];
+ struct mutex *tfm_mutex = NULL;
+ u8 cipher_code;
+ size_t packet_size_length;
+ size_t max_packet_size;
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat =
+ crypt_stat->mount_crypt_stat;
+ struct crypto_skcipher *tfm;
+ struct skcipher_request *req;
+ int rc = 0;
+
+ (*packet_size) = 0;
+ ecryptfs_from_hex(key_rec->sig, auth_tok->token.password.signature,
+ ECRYPTFS_SIG_SIZE);
+ rc = ecryptfs_get_tfm_and_mutex_for_cipher_name(&tfm, &tfm_mutex,
+ crypt_stat->cipher);
+ if (unlikely(rc)) {
+ printk(KERN_ERR "Internal error whilst attempting to get "
+ "tfm and mutex for cipher name [%s]; rc = [%d]\n",
+ crypt_stat->cipher, rc);
+ goto out;
+ }
+ if (mount_crypt_stat->global_default_cipher_key_size == 0) {
+ printk(KERN_WARNING "No key size specified at mount; "
+ "defaulting to [%d]\n",
+ crypto_skcipher_default_keysize(tfm));
+ mount_crypt_stat->global_default_cipher_key_size =
+ crypto_skcipher_default_keysize(tfm);
+ }
+ if (crypt_stat->key_size == 0)
+ crypt_stat->key_size =
+ mount_crypt_stat->global_default_cipher_key_size;
+ if (auth_tok->session_key.encrypted_key_size == 0)
+ auth_tok->session_key.encrypted_key_size =
+ crypt_stat->key_size;
+ if (crypt_stat->key_size == 24
+ && strcmp("aes", crypt_stat->cipher) == 0) {
+ memset((crypt_stat->key + 24), 0, 8);
+ auth_tok->session_key.encrypted_key_size = 32;
+ } else
+ auth_tok->session_key.encrypted_key_size = crypt_stat->key_size;
+ key_rec->enc_key_size =
+ auth_tok->session_key.encrypted_key_size;
+ encrypted_session_key_valid = 0;
+ for (i = 0; i < auth_tok->session_key.encrypted_key_size; i++)
+ encrypted_session_key_valid |=
+ auth_tok->session_key.encrypted_key[i];
+ if (encrypted_session_key_valid) {
+ ecryptfs_printk(KERN_DEBUG, "encrypted_session_key_valid != 0; "
+ "using auth_tok->session_key.encrypted_key, "
+ "where key_rec->enc_key_size = [%zd]\n",
+ key_rec->enc_key_size);
+ memcpy(key_rec->enc_key,
+ auth_tok->session_key.encrypted_key,
+ key_rec->enc_key_size);
+ goto encrypted_session_key_set;
+ }
+ if (auth_tok->token.password.flags &
+ ECRYPTFS_SESSION_KEY_ENCRYPTION_KEY_SET) {
+ ecryptfs_printk(KERN_DEBUG, "Using previously generated "
+ "session key encryption key of size [%d]\n",
+ auth_tok->token.password.
+ session_key_encryption_key_bytes);
+ memcpy(session_key_encryption_key,
+ auth_tok->token.password.session_key_encryption_key,
+ crypt_stat->key_size);
+ ecryptfs_printk(KERN_DEBUG,
+ "Cached session key encryption key:\n");
+ if (ecryptfs_verbosity > 0)
+ ecryptfs_dump_hex(session_key_encryption_key, 16);
+ }
+ if (unlikely(ecryptfs_verbosity > 0)) {
+ ecryptfs_printk(KERN_DEBUG, "Session key encryption key:\n");
+ ecryptfs_dump_hex(session_key_encryption_key, 16);
+ }
+ rc = virt_to_scatterlist(crypt_stat->key, key_rec->enc_key_size,
+ src_sg, 2);
+ if (rc < 1 || rc > 2) {
+ ecryptfs_printk(KERN_ERR, "Error generating scatterlist "
+ "for crypt_stat session key; expected rc = 1; "
+ "got rc = [%d]. key_rec->enc_key_size = [%zd]\n",
+ rc, key_rec->enc_key_size);
+ rc = -ENOMEM;
+ goto out;
+ }
+ rc = virt_to_scatterlist(key_rec->enc_key, key_rec->enc_key_size,
+ dst_sg, 2);
+ if (rc < 1 || rc > 2) {
+ ecryptfs_printk(KERN_ERR, "Error generating scatterlist "
+ "for crypt_stat encrypted session key; "
+ "expected rc = 1; got rc = [%d]. "
+ "key_rec->enc_key_size = [%zd]\n", rc,
+ key_rec->enc_key_size);
+ rc = -ENOMEM;
+ goto out;
+ }
+ mutex_lock(tfm_mutex);
+ rc = crypto_skcipher_setkey(tfm, session_key_encryption_key,
+ crypt_stat->key_size);
+ if (rc < 0) {
+ mutex_unlock(tfm_mutex);
+ ecryptfs_printk(KERN_ERR, "Error setting key for crypto "
+ "context; rc = [%d]\n", rc);
+ goto out;
+ }
+
+ req = skcipher_request_alloc(tfm, GFP_KERNEL);
+ if (!req) {
+ mutex_unlock(tfm_mutex);
+ ecryptfs_printk(KERN_ERR, "Out of kernel memory whilst "
+ "attempting to skcipher_request_alloc for "
+ "%s\n", crypto_skcipher_driver_name(tfm));
+ rc = -ENOMEM;
+ goto out;
+ }
+
+ skcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_SLEEP,
+ NULL, NULL);
+
+ rc = 0;
+ ecryptfs_printk(KERN_DEBUG, "Encrypting [%zd] bytes of the key\n",
+ crypt_stat->key_size);
+ skcipher_request_set_crypt(req, src_sg, dst_sg,
+ (*key_rec).enc_key_size, NULL);
+ rc = crypto_skcipher_encrypt(req);
+ mutex_unlock(tfm_mutex);
+ skcipher_request_free(req);
+ if (rc) {
+ printk(KERN_ERR "Error encrypting; rc = [%d]\n", rc);
+ goto out;
+ }
+ ecryptfs_printk(KERN_DEBUG, "This should be the encrypted key:\n");
+ if (ecryptfs_verbosity > 0) {
+ ecryptfs_printk(KERN_DEBUG, "EFEK of size [%zd]:\n",
+ key_rec->enc_key_size);
+ ecryptfs_dump_hex(key_rec->enc_key,
+ key_rec->enc_key_size);
+ }
+encrypted_session_key_set:
+ /* This format is inspired by OpenPGP; see RFC 2440
+ * packet tag 3 */
+ max_packet_size = (1 /* Tag 3 identifier */
+ + 3 /* Max Tag 3 packet size */
+ + 1 /* Version */
+ + 1 /* Cipher code */
+ + 1 /* S2K specifier */
+ + 1 /* Hash identifier */
+ + ECRYPTFS_SALT_SIZE /* Salt */
+ + 1 /* Hash iterations */
+ + key_rec->enc_key_size); /* Encrypted key size */
+ if (max_packet_size > (*remaining_bytes)) {
+ printk(KERN_ERR "Packet too large; need up to [%td] bytes, but "
+ "there are only [%td] available\n", max_packet_size,
+ (*remaining_bytes));
+ rc = -EINVAL;
+ goto out;
+ }
+ dest[(*packet_size)++] = ECRYPTFS_TAG_3_PACKET_TYPE;
+ /* Chop off the Tag 3 identifier(1) and Tag 3 packet size(3)
+ * to get the number of octets in the actual Tag 3 packet */
+ rc = ecryptfs_write_packet_length(&dest[(*packet_size)],
+ (max_packet_size - 4),
+ &packet_size_length);
+ if (rc) {
+ printk(KERN_ERR "Error generating tag 3 packet header; cannot "
+ "generate packet length. rc = [%d]\n", rc);
+ goto out;
+ }
+ (*packet_size) += packet_size_length;
+ dest[(*packet_size)++] = 0x04; /* version 4 */
+ /* TODO: Break from RFC2440 so that arbitrary ciphers can be
+ * specified with strings */
+ cipher_code = ecryptfs_code_for_cipher_string(crypt_stat->cipher,
+ crypt_stat->key_size);
+ if (cipher_code == 0) {
+ ecryptfs_printk(KERN_WARNING, "Unable to generate code for "
+ "cipher [%s]\n", crypt_stat->cipher);
+ rc = -EINVAL;
+ goto out;
+ }
+ dest[(*packet_size)++] = cipher_code;
+ dest[(*packet_size)++] = 0x03; /* S2K */
+ dest[(*packet_size)++] = 0x01; /* MD5 (TODO: parameterize) */
+ memcpy(&dest[(*packet_size)], auth_tok->token.password.salt,
+ ECRYPTFS_SALT_SIZE);
+ (*packet_size) += ECRYPTFS_SALT_SIZE; /* salt */
+ dest[(*packet_size)++] = 0x60; /* hash iterations (65536) */
+ memcpy(&dest[(*packet_size)], key_rec->enc_key,
+ key_rec->enc_key_size);
+ (*packet_size) += key_rec->enc_key_size;
+out:
+ if (rc)
+ (*packet_size) = 0;
+ else
+ (*remaining_bytes) -= (*packet_size);
+ return rc;
+}
+
+struct kmem_cache *ecryptfs_key_record_cache;
+
+/**
+ * ecryptfs_generate_key_packet_set
+ * @dest_base: Virtual address from which to write the key record set
+ * @crypt_stat: The cryptographic context from which the
+ * authentication tokens will be retrieved
+ * @ecryptfs_dentry: The dentry, used to retrieve the mount crypt stat
+ * for the global parameters
+ * @len: The amount written
+ * @max: The maximum amount of data allowed to be written
+ *
+ * Generates a key packet set and writes it to the virtual address
+ * passed in.
+ *
+ * Returns zero on success; non-zero on error.
+ */
+int
+ecryptfs_generate_key_packet_set(char *dest_base,
+ struct ecryptfs_crypt_stat *crypt_stat,
+ struct dentry *ecryptfs_dentry, size_t *len,
+ size_t max)
+{
+ struct ecryptfs_auth_tok *auth_tok;
+ struct key *auth_tok_key = NULL;
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat =
+ &ecryptfs_superblock_to_private(
+ ecryptfs_dentry->d_sb)->mount_crypt_stat;
+ size_t written;
+ struct ecryptfs_key_record *key_rec;
+ struct ecryptfs_key_sig *key_sig;
+ int rc = 0;
+
+ (*len) = 0;
+ mutex_lock(&crypt_stat->keysig_list_mutex);
+ key_rec = kmem_cache_alloc(ecryptfs_key_record_cache, GFP_KERNEL);
+ if (!key_rec) {
+ rc = -ENOMEM;
+ goto out;
+ }
+ list_for_each_entry(key_sig, &crypt_stat->keysig_list,
+ crypt_stat_list) {
+ memset(key_rec, 0, sizeof(*key_rec));
+ rc = ecryptfs_find_global_auth_tok_for_sig(&auth_tok_key,
+ &auth_tok,
+ mount_crypt_stat,
+ key_sig->keysig);
+ if (rc) {
+ printk(KERN_WARNING "Unable to retrieve auth tok with "
+ "sig = [%s]\n", key_sig->keysig);
+ rc = process_find_global_auth_tok_for_sig_err(rc);
+ goto out_free;
+ }
+ if (auth_tok->token_type == ECRYPTFS_PASSWORD) {
+ rc = write_tag_3_packet((dest_base + (*len)),
+ &max, auth_tok,
+ crypt_stat, key_rec,
+ &written);
+ up_write(&(auth_tok_key->sem));
+ key_put(auth_tok_key);
+ if (rc) {
+ ecryptfs_printk(KERN_WARNING, "Error "
+ "writing tag 3 packet\n");
+ goto out_free;
+ }
+ (*len) += written;
+ /* Write auth tok signature packet */
+ rc = write_tag_11_packet((dest_base + (*len)), &max,
+ key_rec->sig,
+ ECRYPTFS_SIG_SIZE, &written);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error writing "
+ "auth tok signature packet\n");
+ goto out_free;
+ }
+ (*len) += written;
+ } else if (auth_tok->token_type == ECRYPTFS_PRIVATE_KEY) {
+ rc = write_tag_1_packet(dest_base + (*len), &max,
+ auth_tok_key, auth_tok,
+ crypt_stat, key_rec, &written);
+ if (rc) {
+ ecryptfs_printk(KERN_WARNING, "Error "
+ "writing tag 1 packet\n");
+ goto out_free;
+ }
+ (*len) += written;
+ } else {
+ up_write(&(auth_tok_key->sem));
+ key_put(auth_tok_key);
+ ecryptfs_printk(KERN_WARNING, "Unsupported "
+ "authentication token type\n");
+ rc = -EINVAL;
+ goto out_free;
+ }
+ }
+ if (likely(max > 0)) {
+ dest_base[(*len)] = 0x00;
+ } else {
+ ecryptfs_printk(KERN_ERR, "Error writing boundary byte\n");
+ rc = -EIO;
+ }
+out_free:
+ kmem_cache_free(ecryptfs_key_record_cache, key_rec);
+out:
+ if (rc)
+ (*len) = 0;
+ mutex_unlock(&crypt_stat->keysig_list_mutex);
+ return rc;
+}
+
+struct kmem_cache *ecryptfs_key_sig_cache;
+
+int ecryptfs_add_keysig(struct ecryptfs_crypt_stat *crypt_stat, char *sig)
+{
+ struct ecryptfs_key_sig *new_key_sig;
+
+ new_key_sig = kmem_cache_alloc(ecryptfs_key_sig_cache, GFP_KERNEL);
+ if (!new_key_sig)
+ return -ENOMEM;
+
+ memcpy(new_key_sig->keysig, sig, ECRYPTFS_SIG_SIZE_HEX);
+ new_key_sig->keysig[ECRYPTFS_SIG_SIZE_HEX] = '\0';
+ /* Caller must hold keysig_list_mutex */
+ list_add(&new_key_sig->crypt_stat_list, &crypt_stat->keysig_list);
+
+ return 0;
+}
+
+struct kmem_cache *ecryptfs_global_auth_tok_cache;
+
+int
+ecryptfs_add_global_auth_tok(struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
+ char *sig, u32 global_auth_tok_flags)
+{
+ struct ecryptfs_global_auth_tok *new_auth_tok;
+
+ new_auth_tok = kmem_cache_zalloc(ecryptfs_global_auth_tok_cache,
+ GFP_KERNEL);
+ if (!new_auth_tok)
+ return -ENOMEM;
+
+ memcpy(new_auth_tok->sig, sig, ECRYPTFS_SIG_SIZE_HEX);
+ new_auth_tok->flags = global_auth_tok_flags;
+ new_auth_tok->sig[ECRYPTFS_SIG_SIZE_HEX] = '\0';
+ mutex_lock(&mount_crypt_stat->global_auth_tok_list_mutex);
+ list_add(&new_auth_tok->mount_crypt_stat_list,
+ &mount_crypt_stat->global_auth_tok_list);
+ mutex_unlock(&mount_crypt_stat->global_auth_tok_list_mutex);
+ return 0;
+}
+
diff --git a/fs/ecryptfs/kthread.c b/fs/ecryptfs/kthread.c
new file mode 100644
index 0000000..e00d45a
--- /dev/null
+++ b/fs/ecryptfs/kthread.c
@@ -0,0 +1,172 @@
+/**
+ * eCryptfs: Linux filesystem encryption layer
+ *
+ * Copyright (C) 2008 International Business Machines Corp.
+ * Author(s): Michael A. Halcrow <mahalcro@us.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ */
+
+#include <linux/kthread.h>
+#include <linux/freezer.h>
+#include <linux/slab.h>
+#include <linux/wait.h>
+#include <linux/mount.h>
+#include "ecryptfs_kernel.h"
+
+struct ecryptfs_open_req {
+ struct file **lower_file;
+ struct path path;
+ struct completion done;
+ struct list_head kthread_ctl_list;
+};
+
+static struct ecryptfs_kthread_ctl {
+#define ECRYPTFS_KTHREAD_ZOMBIE 0x00000001
+ u32 flags;
+ struct mutex mux;
+ struct list_head req_list;
+ wait_queue_head_t wait;
+} ecryptfs_kthread_ctl;
+
+static struct task_struct *ecryptfs_kthread;
+
+/**
+ * ecryptfs_threadfn
+ * @ignored: ignored
+ *
+ * The eCryptfs kernel thread that has the responsibility of getting
+ * the lower file with RW permissions.
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+static int ecryptfs_threadfn(void *ignored)
+{
+ set_freezable();
+ while (1) {
+ struct ecryptfs_open_req *req;
+
+ wait_event_freezable(
+ ecryptfs_kthread_ctl.wait,
+ (!list_empty(&ecryptfs_kthread_ctl.req_list)
+ || kthread_should_stop()));
+ mutex_lock(&ecryptfs_kthread_ctl.mux);
+ if (ecryptfs_kthread_ctl.flags & ECRYPTFS_KTHREAD_ZOMBIE) {
+ mutex_unlock(&ecryptfs_kthread_ctl.mux);
+ goto out;
+ }
+ while (!list_empty(&ecryptfs_kthread_ctl.req_list)) {
+ req = list_first_entry(&ecryptfs_kthread_ctl.req_list,
+ struct ecryptfs_open_req,
+ kthread_ctl_list);
+ list_del(&req->kthread_ctl_list);
+ *req->lower_file = dentry_open(&req->path,
+ (O_RDWR | O_LARGEFILE), current_cred());
+ complete(&req->done);
+ }
+ mutex_unlock(&ecryptfs_kthread_ctl.mux);
+ }
+out:
+ return 0;
+}
+
+int __init ecryptfs_init_kthread(void)
+{
+ int rc = 0;
+
+ mutex_init(&ecryptfs_kthread_ctl.mux);
+ init_waitqueue_head(&ecryptfs_kthread_ctl.wait);
+ INIT_LIST_HEAD(&ecryptfs_kthread_ctl.req_list);
+ ecryptfs_kthread = kthread_run(&ecryptfs_threadfn, NULL,
+ "ecryptfs-kthread");
+ if (IS_ERR(ecryptfs_kthread)) {
+ rc = PTR_ERR(ecryptfs_kthread);
+ printk(KERN_ERR "%s: Failed to create kernel thread; rc = [%d]"
+ "\n", __func__, rc);
+ }
+ return rc;
+}
+
+void ecryptfs_destroy_kthread(void)
+{
+ struct ecryptfs_open_req *req, *tmp;
+
+ mutex_lock(&ecryptfs_kthread_ctl.mux);
+ ecryptfs_kthread_ctl.flags |= ECRYPTFS_KTHREAD_ZOMBIE;
+ list_for_each_entry_safe(req, tmp, &ecryptfs_kthread_ctl.req_list,
+ kthread_ctl_list) {
+ list_del(&req->kthread_ctl_list);
+ *req->lower_file = ERR_PTR(-EIO);
+ complete(&req->done);
+ }
+ mutex_unlock(&ecryptfs_kthread_ctl.mux);
+ kthread_stop(ecryptfs_kthread);
+ wake_up(&ecryptfs_kthread_ctl.wait);
+}
+
+/**
+ * ecryptfs_privileged_open
+ * @lower_file: Result of dentry_open by root on lower dentry
+ * @lower_dentry: Lower dentry for file to open
+ * @lower_mnt: Lower vfsmount for file to open
+ *
+ * This function gets a r/w file opened against the lower dentry.
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+int ecryptfs_privileged_open(struct file **lower_file,
+ struct dentry *lower_dentry,
+ struct vfsmount *lower_mnt,
+ const struct cred *cred)
+{
+ struct ecryptfs_open_req req;
+ int flags = O_LARGEFILE;
+ int rc = 0;
+
+ init_completion(&req.done);
+ req.lower_file = lower_file;
+ req.path.dentry = lower_dentry;
+ req.path.mnt = lower_mnt;
+
+ /* Corresponding dput() and mntput() are done when the
+ * lower file is fput() when all eCryptfs files for the inode are
+ * released. */
+ flags |= IS_RDONLY(d_inode(lower_dentry)) ? O_RDONLY : O_RDWR;
+ (*lower_file) = dentry_open(&req.path, flags, cred);
+ if (!IS_ERR(*lower_file))
+ goto out;
+ if ((flags & O_ACCMODE) == O_RDONLY) {
+ rc = PTR_ERR((*lower_file));
+ goto out;
+ }
+ mutex_lock(&ecryptfs_kthread_ctl.mux);
+ if (ecryptfs_kthread_ctl.flags & ECRYPTFS_KTHREAD_ZOMBIE) {
+ rc = -EIO;
+ mutex_unlock(&ecryptfs_kthread_ctl.mux);
+ printk(KERN_ERR "%s: We are in the middle of shutting down; "
+ "aborting privileged request to open lower file\n",
+ __func__);
+ goto out;
+ }
+ list_add_tail(&req.kthread_ctl_list, &ecryptfs_kthread_ctl.req_list);
+ mutex_unlock(&ecryptfs_kthread_ctl.mux);
+ wake_up(&ecryptfs_kthread_ctl.wait);
+ wait_for_completion(&req.done);
+ if (IS_ERR(*lower_file))
+ rc = PTR_ERR(*lower_file);
+out:
+ return rc;
+}
diff --git a/fs/ecryptfs/main.c b/fs/ecryptfs/main.c
new file mode 100644
index 0000000..025d66a
--- /dev/null
+++ b/fs/ecryptfs/main.c
@@ -0,0 +1,904 @@
+/**
+ * eCryptfs: Linux filesystem encryption layer
+ *
+ * Copyright (C) 1997-2003 Erez Zadok
+ * Copyright (C) 2001-2003 Stony Brook University
+ * Copyright (C) 2004-2007 International Business Machines Corp.
+ * Author(s): Michael A. Halcrow <mahalcro@us.ibm.com>
+ * Michael C. Thompson <mcthomps@us.ibm.com>
+ * Tyler Hicks <tyhicks@ou.edu>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ */
+
+#include <linux/dcache.h>
+#include <linux/file.h>
+#include <linux/module.h>
+#include <linux/namei.h>
+#include <linux/skbuff.h>
+#include <linux/mount.h>
+#include <linux/pagemap.h>
+#include <linux/key.h>
+#include <linux/parser.h>
+#include <linux/fs_stack.h>
+#include <linux/slab.h>
+#include <linux/magic.h>
+#include "ecryptfs_kernel.h"
+
+/**
+ * Module parameter that defines the ecryptfs_verbosity level.
+ */
+int ecryptfs_verbosity = 0;
+
+module_param(ecryptfs_verbosity, int, 0);
+MODULE_PARM_DESC(ecryptfs_verbosity,
+ "Initial verbosity level (0 or 1; defaults to "
+ "0, which is Quiet)");
+
+/**
+ * Module parameter that defines the number of message buffer elements
+ */
+unsigned int ecryptfs_message_buf_len = ECRYPTFS_DEFAULT_MSG_CTX_ELEMS;
+
+module_param(ecryptfs_message_buf_len, uint, 0);
+MODULE_PARM_DESC(ecryptfs_message_buf_len,
+ "Number of message buffer elements");
+
+/**
+ * Module parameter that defines the maximum guaranteed amount of time to wait
+ * for a response from ecryptfsd. The actual sleep time will be, more than
+ * likely, a small amount greater than this specified value, but only less if
+ * the message successfully arrives.
+ */
+signed long ecryptfs_message_wait_timeout = ECRYPTFS_MAX_MSG_CTX_TTL / HZ;
+
+module_param(ecryptfs_message_wait_timeout, long, 0);
+MODULE_PARM_DESC(ecryptfs_message_wait_timeout,
+ "Maximum number of seconds that an operation will "
+ "sleep while waiting for a message response from "
+ "userspace");
+
+/**
+ * Module parameter that is an estimate of the maximum number of users
+ * that will be concurrently using eCryptfs. Set this to the right
+ * value to balance performance and memory use.
+ */
+unsigned int ecryptfs_number_of_users = ECRYPTFS_DEFAULT_NUM_USERS;
+
+module_param(ecryptfs_number_of_users, uint, 0);
+MODULE_PARM_DESC(ecryptfs_number_of_users, "An estimate of the number of "
+ "concurrent users of eCryptfs");
+
+void __ecryptfs_printk(const char *fmt, ...)
+{
+ va_list args;
+ va_start(args, fmt);
+ if (fmt[1] == '7') { /* KERN_DEBUG */
+ if (ecryptfs_verbosity >= 1)
+ vprintk(fmt, args);
+ } else
+ vprintk(fmt, args);
+ va_end(args);
+}
+
+/**
+ * ecryptfs_init_lower_file
+ * @ecryptfs_dentry: Fully initialized eCryptfs dentry object, with
+ * the lower dentry and the lower mount set
+ *
+ * eCryptfs only ever keeps a single open file for every lower
+ * inode. All I/O operations to the lower inode occur through that
+ * file. When the first eCryptfs dentry that interposes with the first
+ * lower dentry for that inode is created, this function creates the
+ * lower file struct and associates it with the eCryptfs
+ * inode. When all eCryptfs files associated with the inode are released, the
+ * file is closed.
+ *
+ * The lower file will be opened with read/write permissions, if
+ * possible. Otherwise, it is opened read-only.
+ *
+ * This function does nothing if a lower file is already
+ * associated with the eCryptfs inode.
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+static int ecryptfs_init_lower_file(struct dentry *dentry,
+ struct file **lower_file)
+{
+ const struct cred *cred = current_cred();
+ struct path *path = ecryptfs_dentry_to_lower_path(dentry);
+ int rc;
+
+ rc = ecryptfs_privileged_open(lower_file, path->dentry, path->mnt,
+ cred);
+ if (rc) {
+ printk(KERN_ERR "Error opening lower file "
+ "for lower_dentry [0x%p] and lower_mnt [0x%p]; "
+ "rc = [%d]\n", path->dentry, path->mnt, rc);
+ (*lower_file) = NULL;
+ }
+ return rc;
+}
+
+int ecryptfs_get_lower_file(struct dentry *dentry, struct inode *inode)
+{
+ struct ecryptfs_inode_info *inode_info;
+ int count, rc = 0;
+
+ inode_info = ecryptfs_inode_to_private(inode);
+ mutex_lock(&inode_info->lower_file_mutex);
+ count = atomic_inc_return(&inode_info->lower_file_count);
+ if (WARN_ON_ONCE(count < 1))
+ rc = -EINVAL;
+ else if (count == 1) {
+ rc = ecryptfs_init_lower_file(dentry,
+ &inode_info->lower_file);
+ if (rc)
+ atomic_set(&inode_info->lower_file_count, 0);
+ }
+ mutex_unlock(&inode_info->lower_file_mutex);
+ return rc;
+}
+
+void ecryptfs_put_lower_file(struct inode *inode)
+{
+ struct ecryptfs_inode_info *inode_info;
+
+ inode_info = ecryptfs_inode_to_private(inode);
+ if (atomic_dec_and_mutex_lock(&inode_info->lower_file_count,
+ &inode_info->lower_file_mutex)) {
+ filemap_write_and_wait(inode->i_mapping);
+ fput(inode_info->lower_file);
+ inode_info->lower_file = NULL;
+ mutex_unlock(&inode_info->lower_file_mutex);
+ }
+}
+
+enum { ecryptfs_opt_sig, ecryptfs_opt_ecryptfs_sig,
+ ecryptfs_opt_cipher, ecryptfs_opt_ecryptfs_cipher,
+ ecryptfs_opt_ecryptfs_key_bytes,
+ ecryptfs_opt_passthrough, ecryptfs_opt_xattr_metadata,
+ ecryptfs_opt_encrypted_view, ecryptfs_opt_fnek_sig,
+ ecryptfs_opt_fn_cipher, ecryptfs_opt_fn_cipher_key_bytes,
+ ecryptfs_opt_unlink_sigs, ecryptfs_opt_mount_auth_tok_only,
+ ecryptfs_opt_check_dev_ruid,
+ ecryptfs_opt_err };
+
+static const match_table_t tokens = {
+ {ecryptfs_opt_sig, "sig=%s"},
+ {ecryptfs_opt_ecryptfs_sig, "ecryptfs_sig=%s"},
+ {ecryptfs_opt_cipher, "cipher=%s"},
+ {ecryptfs_opt_ecryptfs_cipher, "ecryptfs_cipher=%s"},
+ {ecryptfs_opt_ecryptfs_key_bytes, "ecryptfs_key_bytes=%u"},
+ {ecryptfs_opt_passthrough, "ecryptfs_passthrough"},
+ {ecryptfs_opt_xattr_metadata, "ecryptfs_xattr_metadata"},
+ {ecryptfs_opt_encrypted_view, "ecryptfs_encrypted_view"},
+ {ecryptfs_opt_fnek_sig, "ecryptfs_fnek_sig=%s"},
+ {ecryptfs_opt_fn_cipher, "ecryptfs_fn_cipher=%s"},
+ {ecryptfs_opt_fn_cipher_key_bytes, "ecryptfs_fn_key_bytes=%u"},
+ {ecryptfs_opt_unlink_sigs, "ecryptfs_unlink_sigs"},
+ {ecryptfs_opt_mount_auth_tok_only, "ecryptfs_mount_auth_tok_only"},
+ {ecryptfs_opt_check_dev_ruid, "ecryptfs_check_dev_ruid"},
+ {ecryptfs_opt_err, NULL}
+};
+
+static int ecryptfs_init_global_auth_toks(
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat)
+{
+ struct ecryptfs_global_auth_tok *global_auth_tok;
+ struct ecryptfs_auth_tok *auth_tok;
+ int rc = 0;
+
+ list_for_each_entry(global_auth_tok,
+ &mount_crypt_stat->global_auth_tok_list,
+ mount_crypt_stat_list) {
+ rc = ecryptfs_keyring_auth_tok_for_sig(
+ &global_auth_tok->global_auth_tok_key, &auth_tok,
+ global_auth_tok->sig);
+ if (rc) {
+ printk(KERN_ERR "Could not find valid key in user "
+ "session keyring for sig specified in mount "
+ "option: [%s]\n", global_auth_tok->sig);
+ global_auth_tok->flags |= ECRYPTFS_AUTH_TOK_INVALID;
+ goto out;
+ } else {
+ global_auth_tok->flags &= ~ECRYPTFS_AUTH_TOK_INVALID;
+ up_write(&(global_auth_tok->global_auth_tok_key)->sem);
+ }
+ }
+out:
+ return rc;
+}
+
+static void ecryptfs_init_mount_crypt_stat(
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat)
+{
+ memset((void *)mount_crypt_stat, 0,
+ sizeof(struct ecryptfs_mount_crypt_stat));
+ INIT_LIST_HEAD(&mount_crypt_stat->global_auth_tok_list);
+ mutex_init(&mount_crypt_stat->global_auth_tok_list_mutex);
+ mount_crypt_stat->flags |= ECRYPTFS_MOUNT_CRYPT_STAT_INITIALIZED;
+}
+
+/**
+ * ecryptfs_parse_options
+ * @sb: The ecryptfs super block
+ * @options: The options passed to the kernel
+ * @check_ruid: set to 1 if device uid should be checked against the ruid
+ *
+ * Parse mount options:
+ * debug=N - ecryptfs_verbosity level for debug output
+ * sig=XXX - description(signature) of the key to use
+ *
+ * Returns the dentry object of the lower-level (lower/interposed)
+ * directory; We want to mount our stackable file system on top of
+ * that lower directory.
+ *
+ * The signature of the key to use must be the description of a key
+ * already in the keyring. Mounting will fail if the key can not be
+ * found.
+ *
+ * Returns zero on success; non-zero on error
+ */
+static int ecryptfs_parse_options(struct ecryptfs_sb_info *sbi, char *options,
+ uid_t *check_ruid)
+{
+ char *p;
+ int rc = 0;
+ int sig_set = 0;
+ int cipher_name_set = 0;
+ int fn_cipher_name_set = 0;
+ int cipher_key_bytes;
+ int cipher_key_bytes_set = 0;
+ int fn_cipher_key_bytes;
+ int fn_cipher_key_bytes_set = 0;
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat =
+ &sbi->mount_crypt_stat;
+ substring_t args[MAX_OPT_ARGS];
+ int token;
+ char *sig_src;
+ char *cipher_name_dst;
+ char *cipher_name_src;
+ char *fn_cipher_name_dst;
+ char *fn_cipher_name_src;
+ char *fnek_dst;
+ char *fnek_src;
+ char *cipher_key_bytes_src;
+ char *fn_cipher_key_bytes_src;
+ u8 cipher_code;
+
+ *check_ruid = 0;
+
+ if (!options) {
+ rc = -EINVAL;
+ goto out;
+ }
+ ecryptfs_init_mount_crypt_stat(mount_crypt_stat);
+ while ((p = strsep(&options, ",")) != NULL) {
+ if (!*p)
+ continue;
+ token = match_token(p, tokens, args);
+ switch (token) {
+ case ecryptfs_opt_sig:
+ case ecryptfs_opt_ecryptfs_sig:
+ sig_src = args[0].from;
+ rc = ecryptfs_add_global_auth_tok(mount_crypt_stat,
+ sig_src, 0);
+ if (rc) {
+ printk(KERN_ERR "Error attempting to register "
+ "global sig; rc = [%d]\n", rc);
+ goto out;
+ }
+ sig_set = 1;
+ break;
+ case ecryptfs_opt_cipher:
+ case ecryptfs_opt_ecryptfs_cipher:
+ cipher_name_src = args[0].from;
+ cipher_name_dst =
+ mount_crypt_stat->
+ global_default_cipher_name;
+ strncpy(cipher_name_dst, cipher_name_src,
+ ECRYPTFS_MAX_CIPHER_NAME_SIZE);
+ cipher_name_dst[ECRYPTFS_MAX_CIPHER_NAME_SIZE] = '\0';
+ cipher_name_set = 1;
+ break;
+ case ecryptfs_opt_ecryptfs_key_bytes:
+ cipher_key_bytes_src = args[0].from;
+ cipher_key_bytes =
+ (int)simple_strtol(cipher_key_bytes_src,
+ &cipher_key_bytes_src, 0);
+ mount_crypt_stat->global_default_cipher_key_size =
+ cipher_key_bytes;
+ cipher_key_bytes_set = 1;
+ break;
+ case ecryptfs_opt_passthrough:
+ mount_crypt_stat->flags |=
+ ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED;
+ break;
+ case ecryptfs_opt_xattr_metadata:
+ mount_crypt_stat->flags |=
+ ECRYPTFS_XATTR_METADATA_ENABLED;
+ break;
+ case ecryptfs_opt_encrypted_view:
+ mount_crypt_stat->flags |=
+ ECRYPTFS_XATTR_METADATA_ENABLED;
+ mount_crypt_stat->flags |=
+ ECRYPTFS_ENCRYPTED_VIEW_ENABLED;
+ break;
+ case ecryptfs_opt_fnek_sig:
+ fnek_src = args[0].from;
+ fnek_dst =
+ mount_crypt_stat->global_default_fnek_sig;
+ strncpy(fnek_dst, fnek_src, ECRYPTFS_SIG_SIZE_HEX);
+ mount_crypt_stat->global_default_fnek_sig[
+ ECRYPTFS_SIG_SIZE_HEX] = '\0';
+ rc = ecryptfs_add_global_auth_tok(
+ mount_crypt_stat,
+ mount_crypt_stat->global_default_fnek_sig,
+ ECRYPTFS_AUTH_TOK_FNEK);
+ if (rc) {
+ printk(KERN_ERR "Error attempting to register "
+ "global fnek sig [%s]; rc = [%d]\n",
+ mount_crypt_stat->global_default_fnek_sig,
+ rc);
+ goto out;
+ }
+ mount_crypt_stat->flags |=
+ (ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES
+ | ECRYPTFS_GLOBAL_ENCFN_USE_MOUNT_FNEK);
+ break;
+ case ecryptfs_opt_fn_cipher:
+ fn_cipher_name_src = args[0].from;
+ fn_cipher_name_dst =
+ mount_crypt_stat->global_default_fn_cipher_name;
+ strncpy(fn_cipher_name_dst, fn_cipher_name_src,
+ ECRYPTFS_MAX_CIPHER_NAME_SIZE);
+ mount_crypt_stat->global_default_fn_cipher_name[
+ ECRYPTFS_MAX_CIPHER_NAME_SIZE] = '\0';
+ fn_cipher_name_set = 1;
+ break;
+ case ecryptfs_opt_fn_cipher_key_bytes:
+ fn_cipher_key_bytes_src = args[0].from;
+ fn_cipher_key_bytes =
+ (int)simple_strtol(fn_cipher_key_bytes_src,
+ &fn_cipher_key_bytes_src, 0);
+ mount_crypt_stat->global_default_fn_cipher_key_bytes =
+ fn_cipher_key_bytes;
+ fn_cipher_key_bytes_set = 1;
+ break;
+ case ecryptfs_opt_unlink_sigs:
+ mount_crypt_stat->flags |= ECRYPTFS_UNLINK_SIGS;
+ break;
+ case ecryptfs_opt_mount_auth_tok_only:
+ mount_crypt_stat->flags |=
+ ECRYPTFS_GLOBAL_MOUNT_AUTH_TOK_ONLY;
+ break;
+ case ecryptfs_opt_check_dev_ruid:
+ *check_ruid = 1;
+ break;
+ case ecryptfs_opt_err:
+ default:
+ printk(KERN_WARNING
+ "%s: eCryptfs: unrecognized option [%s]\n",
+ __func__, p);
+ }
+ }
+ if (!sig_set) {
+ rc = -EINVAL;
+ ecryptfs_printk(KERN_ERR, "You must supply at least one valid "
+ "auth tok signature as a mount "
+ "parameter; see the eCryptfs README\n");
+ goto out;
+ }
+ if (!cipher_name_set) {
+ int cipher_name_len = strlen(ECRYPTFS_DEFAULT_CIPHER);
+
+ BUG_ON(cipher_name_len > ECRYPTFS_MAX_CIPHER_NAME_SIZE);
+ strcpy(mount_crypt_stat->global_default_cipher_name,
+ ECRYPTFS_DEFAULT_CIPHER);
+ }
+ if ((mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES)
+ && !fn_cipher_name_set)
+ strcpy(mount_crypt_stat->global_default_fn_cipher_name,
+ mount_crypt_stat->global_default_cipher_name);
+ if (!cipher_key_bytes_set)
+ mount_crypt_stat->global_default_cipher_key_size = 0;
+ if ((mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES)
+ && !fn_cipher_key_bytes_set)
+ mount_crypt_stat->global_default_fn_cipher_key_bytes =
+ mount_crypt_stat->global_default_cipher_key_size;
+
+ cipher_code = ecryptfs_code_for_cipher_string(
+ mount_crypt_stat->global_default_cipher_name,
+ mount_crypt_stat->global_default_cipher_key_size);
+ if (!cipher_code) {
+ ecryptfs_printk(KERN_ERR,
+ "eCryptfs doesn't support cipher: %s\n",
+ mount_crypt_stat->global_default_cipher_name);
+ rc = -EINVAL;
+ goto out;
+ }
+
+ mutex_lock(&key_tfm_list_mutex);
+ if (!ecryptfs_tfm_exists(mount_crypt_stat->global_default_cipher_name,
+ NULL)) {
+ rc = ecryptfs_add_new_key_tfm(
+ NULL, mount_crypt_stat->global_default_cipher_name,
+ mount_crypt_stat->global_default_cipher_key_size);
+ if (rc) {
+ printk(KERN_ERR "Error attempting to initialize "
+ "cipher with name = [%s] and key size = [%td]; "
+ "rc = [%d]\n",
+ mount_crypt_stat->global_default_cipher_name,
+ mount_crypt_stat->global_default_cipher_key_size,
+ rc);
+ rc = -EINVAL;
+ mutex_unlock(&key_tfm_list_mutex);
+ goto out;
+ }
+ }
+ if ((mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES)
+ && !ecryptfs_tfm_exists(
+ mount_crypt_stat->global_default_fn_cipher_name, NULL)) {
+ rc = ecryptfs_add_new_key_tfm(
+ NULL, mount_crypt_stat->global_default_fn_cipher_name,
+ mount_crypt_stat->global_default_fn_cipher_key_bytes);
+ if (rc) {
+ printk(KERN_ERR "Error attempting to initialize "
+ "cipher with name = [%s] and key size = [%td]; "
+ "rc = [%d]\n",
+ mount_crypt_stat->global_default_fn_cipher_name,
+ mount_crypt_stat->global_default_fn_cipher_key_bytes,
+ rc);
+ rc = -EINVAL;
+ mutex_unlock(&key_tfm_list_mutex);
+ goto out;
+ }
+ }
+ mutex_unlock(&key_tfm_list_mutex);
+ rc = ecryptfs_init_global_auth_toks(mount_crypt_stat);
+ if (rc)
+ printk(KERN_WARNING "One or more global auth toks could not "
+ "properly register; rc = [%d]\n", rc);
+out:
+ return rc;
+}
+
+struct kmem_cache *ecryptfs_sb_info_cache;
+static struct file_system_type ecryptfs_fs_type;
+
+/**
+ * ecryptfs_get_sb
+ * @fs_type
+ * @flags
+ * @dev_name: The path to mount over
+ * @raw_data: The options passed into the kernel
+ */
+static struct dentry *ecryptfs_mount(struct file_system_type *fs_type, int flags,
+ const char *dev_name, void *raw_data)
+{
+ struct super_block *s;
+ struct ecryptfs_sb_info *sbi;
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
+ struct ecryptfs_dentry_info *root_info;
+ const char *err = "Getting sb failed";
+ struct inode *inode;
+ struct path path;
+ uid_t check_ruid;
+ int rc;
+
+ sbi = kmem_cache_zalloc(ecryptfs_sb_info_cache, GFP_KERNEL);
+ if (!sbi) {
+ rc = -ENOMEM;
+ goto out;
+ }
+
+ rc = ecryptfs_parse_options(sbi, raw_data, &check_ruid);
+ if (rc) {
+ err = "Error parsing options";
+ goto out;
+ }
+ mount_crypt_stat = &sbi->mount_crypt_stat;
+
+ s = sget(fs_type, NULL, set_anon_super, flags, NULL);
+ if (IS_ERR(s)) {
+ rc = PTR_ERR(s);
+ goto out;
+ }
+
+ rc = super_setup_bdi(s);
+ if (rc)
+ goto out1;
+
+ ecryptfs_set_superblock_private(s, sbi);
+
+ /* ->kill_sb() will take care of sbi after that point */
+ sbi = NULL;
+ s->s_op = &ecryptfs_sops;
+ s->s_xattr = ecryptfs_xattr_handlers;
+ s->s_d_op = &ecryptfs_dops;
+
+ err = "Reading sb failed";
+ rc = kern_path(dev_name, LOOKUP_FOLLOW | LOOKUP_DIRECTORY, &path);
+ if (rc) {
+ ecryptfs_printk(KERN_WARNING, "kern_path() failed\n");
+ goto out1;
+ }
+ if (path.dentry->d_sb->s_type == &ecryptfs_fs_type) {
+ rc = -EINVAL;
+ printk(KERN_ERR "Mount on filesystem of type "
+ "eCryptfs explicitly disallowed due to "
+ "known incompatibilities\n");
+ goto out_free;
+ }
+
+ if (check_ruid && !uid_eq(d_inode(path.dentry)->i_uid, current_uid())) {
+ rc = -EPERM;
+ printk(KERN_ERR "Mount of device (uid: %d) not owned by "
+ "requested user (uid: %d)\n",
+ i_uid_read(d_inode(path.dentry)),
+ from_kuid(&init_user_ns, current_uid()));
+ goto out_free;
+ }
+
+ ecryptfs_set_superblock_lower(s, path.dentry->d_sb);
+
+ /**
+ * Set the POSIX ACL flag based on whether they're enabled in the lower
+ * mount.
+ */
+ s->s_flags = flags & ~SB_POSIXACL;
+ s->s_flags |= path.dentry->d_sb->s_flags & SB_POSIXACL;
+
+ /**
+ * Force a read-only eCryptfs mount when:
+ * 1) The lower mount is ro
+ * 2) The ecryptfs_encrypted_view mount option is specified
+ */
+ if (sb_rdonly(path.dentry->d_sb) || mount_crypt_stat->flags & ECRYPTFS_ENCRYPTED_VIEW_ENABLED)
+ s->s_flags |= SB_RDONLY;
+
+ s->s_maxbytes = path.dentry->d_sb->s_maxbytes;
+ s->s_blocksize = path.dentry->d_sb->s_blocksize;
+ s->s_magic = ECRYPTFS_SUPER_MAGIC;
+ s->s_stack_depth = path.dentry->d_sb->s_stack_depth + 1;
+
+ rc = -EINVAL;
+ if (s->s_stack_depth > FILESYSTEM_MAX_STACK_DEPTH) {
+ pr_err("eCryptfs: maximum fs stacking depth exceeded\n");
+ goto out_free;
+ }
+
+ inode = ecryptfs_get_inode(d_inode(path.dentry), s);
+ rc = PTR_ERR(inode);
+ if (IS_ERR(inode))
+ goto out_free;
+
+ s->s_root = d_make_root(inode);
+ if (!s->s_root) {
+ rc = -ENOMEM;
+ goto out_free;
+ }
+
+ rc = -ENOMEM;
+ root_info = kmem_cache_zalloc(ecryptfs_dentry_info_cache, GFP_KERNEL);
+ if (!root_info)
+ goto out_free;
+
+ /* ->kill_sb() will take care of root_info */
+ ecryptfs_set_dentry_private(s->s_root, root_info);
+ root_info->lower_path = path;
+
+ s->s_flags |= SB_ACTIVE;
+ return dget(s->s_root);
+
+out_free:
+ path_put(&path);
+out1:
+ deactivate_locked_super(s);
+out:
+ if (sbi) {
+ ecryptfs_destroy_mount_crypt_stat(&sbi->mount_crypt_stat);
+ kmem_cache_free(ecryptfs_sb_info_cache, sbi);
+ }
+ printk(KERN_ERR "%s; rc = [%d]\n", err, rc);
+ return ERR_PTR(rc);
+}
+
+/**
+ * ecryptfs_kill_block_super
+ * @sb: The ecryptfs super block
+ *
+ * Used to bring the superblock down and free the private data.
+ */
+static void ecryptfs_kill_block_super(struct super_block *sb)
+{
+ struct ecryptfs_sb_info *sb_info = ecryptfs_superblock_to_private(sb);
+ kill_anon_super(sb);
+ if (!sb_info)
+ return;
+ ecryptfs_destroy_mount_crypt_stat(&sb_info->mount_crypt_stat);
+ kmem_cache_free(ecryptfs_sb_info_cache, sb_info);
+}
+
+static struct file_system_type ecryptfs_fs_type = {
+ .owner = THIS_MODULE,
+ .name = "ecryptfs",
+ .mount = ecryptfs_mount,
+ .kill_sb = ecryptfs_kill_block_super,
+ .fs_flags = 0
+};
+MODULE_ALIAS_FS("ecryptfs");
+
+/**
+ * inode_info_init_once
+ *
+ * Initializes the ecryptfs_inode_info_cache when it is created
+ */
+static void
+inode_info_init_once(void *vptr)
+{
+ struct ecryptfs_inode_info *ei = (struct ecryptfs_inode_info *)vptr;
+
+ inode_init_once(&ei->vfs_inode);
+}
+
+static struct ecryptfs_cache_info {
+ struct kmem_cache **cache;
+ const char *name;
+ size_t size;
+ slab_flags_t flags;
+ void (*ctor)(void *obj);
+} ecryptfs_cache_infos[] = {
+ {
+ .cache = &ecryptfs_auth_tok_list_item_cache,
+ .name = "ecryptfs_auth_tok_list_item",
+ .size = sizeof(struct ecryptfs_auth_tok_list_item),
+ },
+ {
+ .cache = &ecryptfs_file_info_cache,
+ .name = "ecryptfs_file_cache",
+ .size = sizeof(struct ecryptfs_file_info),
+ },
+ {
+ .cache = &ecryptfs_dentry_info_cache,
+ .name = "ecryptfs_dentry_info_cache",
+ .size = sizeof(struct ecryptfs_dentry_info),
+ },
+ {
+ .cache = &ecryptfs_inode_info_cache,
+ .name = "ecryptfs_inode_cache",
+ .size = sizeof(struct ecryptfs_inode_info),
+ .flags = SLAB_ACCOUNT,
+ .ctor = inode_info_init_once,
+ },
+ {
+ .cache = &ecryptfs_sb_info_cache,
+ .name = "ecryptfs_sb_cache",
+ .size = sizeof(struct ecryptfs_sb_info),
+ },
+ {
+ .cache = &ecryptfs_header_cache,
+ .name = "ecryptfs_headers",
+ .size = PAGE_SIZE,
+ },
+ {
+ .cache = &ecryptfs_xattr_cache,
+ .name = "ecryptfs_xattr_cache",
+ .size = PAGE_SIZE,
+ },
+ {
+ .cache = &ecryptfs_key_record_cache,
+ .name = "ecryptfs_key_record_cache",
+ .size = sizeof(struct ecryptfs_key_record),
+ },
+ {
+ .cache = &ecryptfs_key_sig_cache,
+ .name = "ecryptfs_key_sig_cache",
+ .size = sizeof(struct ecryptfs_key_sig),
+ },
+ {
+ .cache = &ecryptfs_global_auth_tok_cache,
+ .name = "ecryptfs_global_auth_tok_cache",
+ .size = sizeof(struct ecryptfs_global_auth_tok),
+ },
+ {
+ .cache = &ecryptfs_key_tfm_cache,
+ .name = "ecryptfs_key_tfm_cache",
+ .size = sizeof(struct ecryptfs_key_tfm),
+ },
+};
+
+static void ecryptfs_free_kmem_caches(void)
+{
+ int i;
+
+ /*
+ * Make sure all delayed rcu free inodes are flushed before we
+ * destroy cache.
+ */
+ rcu_barrier();
+
+ for (i = 0; i < ARRAY_SIZE(ecryptfs_cache_infos); i++) {
+ struct ecryptfs_cache_info *info;
+
+ info = &ecryptfs_cache_infos[i];
+ kmem_cache_destroy(*(info->cache));
+ }
+}
+
+/**
+ * ecryptfs_init_kmem_caches
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+static int ecryptfs_init_kmem_caches(void)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(ecryptfs_cache_infos); i++) {
+ struct ecryptfs_cache_info *info;
+
+ info = &ecryptfs_cache_infos[i];
+ *(info->cache) = kmem_cache_create(info->name, info->size, 0,
+ SLAB_HWCACHE_ALIGN | info->flags, info->ctor);
+ if (!*(info->cache)) {
+ ecryptfs_free_kmem_caches();
+ ecryptfs_printk(KERN_WARNING, "%s: "
+ "kmem_cache_create failed\n",
+ info->name);
+ return -ENOMEM;
+ }
+ }
+ return 0;
+}
+
+static struct kobject *ecryptfs_kobj;
+
+static ssize_t version_show(struct kobject *kobj,
+ struct kobj_attribute *attr, char *buff)
+{
+ return snprintf(buff, PAGE_SIZE, "%d\n", ECRYPTFS_VERSIONING_MASK);
+}
+
+static struct kobj_attribute version_attr = __ATTR_RO(version);
+
+static struct attribute *attributes[] = {
+ &version_attr.attr,
+ NULL,
+};
+
+static const struct attribute_group attr_group = {
+ .attrs = attributes,
+};
+
+static int do_sysfs_registration(void)
+{
+ int rc;
+
+ ecryptfs_kobj = kobject_create_and_add("ecryptfs", fs_kobj);
+ if (!ecryptfs_kobj) {
+ printk(KERN_ERR "Unable to create ecryptfs kset\n");
+ rc = -ENOMEM;
+ goto out;
+ }
+ rc = sysfs_create_group(ecryptfs_kobj, &attr_group);
+ if (rc) {
+ printk(KERN_ERR
+ "Unable to create ecryptfs version attributes\n");
+ kobject_put(ecryptfs_kobj);
+ }
+out:
+ return rc;
+}
+
+static void do_sysfs_unregistration(void)
+{
+ sysfs_remove_group(ecryptfs_kobj, &attr_group);
+ kobject_put(ecryptfs_kobj);
+}
+
+static int __init ecryptfs_init(void)
+{
+ int rc;
+
+ if (ECRYPTFS_DEFAULT_EXTENT_SIZE > PAGE_SIZE) {
+ rc = -EINVAL;
+ ecryptfs_printk(KERN_ERR, "The eCryptfs extent size is "
+ "larger than the host's page size, and so "
+ "eCryptfs cannot run on this system. The "
+ "default eCryptfs extent size is [%u] bytes; "
+ "the page size is [%lu] bytes.\n",
+ ECRYPTFS_DEFAULT_EXTENT_SIZE,
+ (unsigned long)PAGE_SIZE);
+ goto out;
+ }
+ rc = ecryptfs_init_kmem_caches();
+ if (rc) {
+ printk(KERN_ERR
+ "Failed to allocate one or more kmem_cache objects\n");
+ goto out;
+ }
+ rc = do_sysfs_registration();
+ if (rc) {
+ printk(KERN_ERR "sysfs registration failed\n");
+ goto out_free_kmem_caches;
+ }
+ rc = ecryptfs_init_kthread();
+ if (rc) {
+ printk(KERN_ERR "%s: kthread initialization failed; "
+ "rc = [%d]\n", __func__, rc);
+ goto out_do_sysfs_unregistration;
+ }
+ rc = ecryptfs_init_messaging();
+ if (rc) {
+ printk(KERN_ERR "Failure occurred while attempting to "
+ "initialize the communications channel to "
+ "ecryptfsd\n");
+ goto out_destroy_kthread;
+ }
+ rc = ecryptfs_init_crypto();
+ if (rc) {
+ printk(KERN_ERR "Failure whilst attempting to init crypto; "
+ "rc = [%d]\n", rc);
+ goto out_release_messaging;
+ }
+ rc = register_filesystem(&ecryptfs_fs_type);
+ if (rc) {
+ printk(KERN_ERR "Failed to register filesystem\n");
+ goto out_destroy_crypto;
+ }
+ if (ecryptfs_verbosity > 0)
+ printk(KERN_CRIT "eCryptfs verbosity set to %d. Secret values "
+ "will be written to the syslog!\n", ecryptfs_verbosity);
+
+ goto out;
+out_destroy_crypto:
+ ecryptfs_destroy_crypto();
+out_release_messaging:
+ ecryptfs_release_messaging();
+out_destroy_kthread:
+ ecryptfs_destroy_kthread();
+out_do_sysfs_unregistration:
+ do_sysfs_unregistration();
+out_free_kmem_caches:
+ ecryptfs_free_kmem_caches();
+out:
+ return rc;
+}
+
+static void __exit ecryptfs_exit(void)
+{
+ int rc;
+
+ rc = ecryptfs_destroy_crypto();
+ if (rc)
+ printk(KERN_ERR "Failure whilst attempting to destroy crypto; "
+ "rc = [%d]\n", rc);
+ ecryptfs_release_messaging();
+ ecryptfs_destroy_kthread();
+ do_sysfs_unregistration();
+ unregister_filesystem(&ecryptfs_fs_type);
+ ecryptfs_free_kmem_caches();
+}
+
+MODULE_AUTHOR("Michael A. Halcrow <mhalcrow@us.ibm.com>");
+MODULE_DESCRIPTION("eCryptfs");
+
+MODULE_LICENSE("GPL");
+
+module_init(ecryptfs_init)
+module_exit(ecryptfs_exit)
diff --git a/fs/ecryptfs/messaging.c b/fs/ecryptfs/messaging.c
new file mode 100644
index 0000000..9fdd5bc
--- /dev/null
+++ b/fs/ecryptfs/messaging.c
@@ -0,0 +1,463 @@
+/**
+ * eCryptfs: Linux filesystem encryption layer
+ *
+ * Copyright (C) 2004-2008 International Business Machines Corp.
+ * Author(s): Michael A. Halcrow <mhalcrow@us.ibm.com>
+ * Tyler Hicks <tyhicks@ou.edu>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version
+ * 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ */
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/user_namespace.h>
+#include <linux/nsproxy.h>
+#include "ecryptfs_kernel.h"
+
+static LIST_HEAD(ecryptfs_msg_ctx_free_list);
+static LIST_HEAD(ecryptfs_msg_ctx_alloc_list);
+static struct mutex ecryptfs_msg_ctx_lists_mux;
+
+static struct hlist_head *ecryptfs_daemon_hash;
+struct mutex ecryptfs_daemon_hash_mux;
+static int ecryptfs_hash_bits;
+#define ecryptfs_current_euid_hash(uid) \
+ hash_long((unsigned long)from_kuid(&init_user_ns, current_euid()), ecryptfs_hash_bits)
+
+static u32 ecryptfs_msg_counter;
+static struct ecryptfs_msg_ctx *ecryptfs_msg_ctx_arr;
+
+/**
+ * ecryptfs_acquire_free_msg_ctx
+ * @msg_ctx: The context that was acquired from the free list
+ *
+ * Acquires a context element from the free list and locks the mutex
+ * on the context. Sets the msg_ctx task to current. Returns zero on
+ * success; non-zero on error or upon failure to acquire a free
+ * context element. Must be called with ecryptfs_msg_ctx_lists_mux
+ * held.
+ */
+static int ecryptfs_acquire_free_msg_ctx(struct ecryptfs_msg_ctx **msg_ctx)
+{
+ struct list_head *p;
+ int rc;
+
+ if (list_empty(&ecryptfs_msg_ctx_free_list)) {
+ printk(KERN_WARNING "%s: The eCryptfs free "
+ "context list is empty. It may be helpful to "
+ "specify the ecryptfs_message_buf_len "
+ "parameter to be greater than the current "
+ "value of [%d]\n", __func__, ecryptfs_message_buf_len);
+ rc = -ENOMEM;
+ goto out;
+ }
+ list_for_each(p, &ecryptfs_msg_ctx_free_list) {
+ *msg_ctx = list_entry(p, struct ecryptfs_msg_ctx, node);
+ if (mutex_trylock(&(*msg_ctx)->mux)) {
+ (*msg_ctx)->task = current;
+ rc = 0;
+ goto out;
+ }
+ }
+ rc = -ENOMEM;
+out:
+ return rc;
+}
+
+/**
+ * ecryptfs_msg_ctx_free_to_alloc
+ * @msg_ctx: The context to move from the free list to the alloc list
+ *
+ * Must be called with ecryptfs_msg_ctx_lists_mux held.
+ */
+static void ecryptfs_msg_ctx_free_to_alloc(struct ecryptfs_msg_ctx *msg_ctx)
+{
+ list_move(&msg_ctx->node, &ecryptfs_msg_ctx_alloc_list);
+ msg_ctx->state = ECRYPTFS_MSG_CTX_STATE_PENDING;
+ msg_ctx->counter = ++ecryptfs_msg_counter;
+}
+
+/**
+ * ecryptfs_msg_ctx_alloc_to_free
+ * @msg_ctx: The context to move from the alloc list to the free list
+ *
+ * Must be called with ecryptfs_msg_ctx_lists_mux held.
+ */
+void ecryptfs_msg_ctx_alloc_to_free(struct ecryptfs_msg_ctx *msg_ctx)
+{
+ list_move(&(msg_ctx->node), &ecryptfs_msg_ctx_free_list);
+ kfree(msg_ctx->msg);
+ msg_ctx->msg = NULL;
+ msg_ctx->state = ECRYPTFS_MSG_CTX_STATE_FREE;
+}
+
+/**
+ * ecryptfs_find_daemon_by_euid
+ * @daemon: If return value is zero, points to the desired daemon pointer
+ *
+ * Must be called with ecryptfs_daemon_hash_mux held.
+ *
+ * Search the hash list for the current effective user id.
+ *
+ * Returns zero if the user id exists in the list; non-zero otherwise.
+ */
+int ecryptfs_find_daemon_by_euid(struct ecryptfs_daemon **daemon)
+{
+ int rc;
+
+ hlist_for_each_entry(*daemon,
+ &ecryptfs_daemon_hash[ecryptfs_current_euid_hash()],
+ euid_chain) {
+ if (uid_eq((*daemon)->file->f_cred->euid, current_euid())) {
+ rc = 0;
+ goto out;
+ }
+ }
+ rc = -EINVAL;
+out:
+ return rc;
+}
+
+/**
+ * ecryptfs_spawn_daemon - Create and initialize a new daemon struct
+ * @daemon: Pointer to set to newly allocated daemon struct
+ * @file: File used when opening /dev/ecryptfs
+ *
+ * Must be called ceremoniously while in possession of
+ * ecryptfs_sacred_daemon_hash_mux
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+int
+ecryptfs_spawn_daemon(struct ecryptfs_daemon **daemon, struct file *file)
+{
+ int rc = 0;
+
+ (*daemon) = kzalloc(sizeof(**daemon), GFP_KERNEL);
+ if (!(*daemon)) {
+ rc = -ENOMEM;
+ goto out;
+ }
+ (*daemon)->file = file;
+ mutex_init(&(*daemon)->mux);
+ INIT_LIST_HEAD(&(*daemon)->msg_ctx_out_queue);
+ init_waitqueue_head(&(*daemon)->wait);
+ (*daemon)->num_queued_msg_ctx = 0;
+ hlist_add_head(&(*daemon)->euid_chain,
+ &ecryptfs_daemon_hash[ecryptfs_current_euid_hash()]);
+out:
+ return rc;
+}
+
+/**
+ * ecryptfs_exorcise_daemon - Destroy the daemon struct
+ *
+ * Must be called ceremoniously while in possession of
+ * ecryptfs_daemon_hash_mux and the daemon's own mux.
+ */
+int ecryptfs_exorcise_daemon(struct ecryptfs_daemon *daemon)
+{
+ struct ecryptfs_msg_ctx *msg_ctx, *msg_ctx_tmp;
+ int rc = 0;
+
+ mutex_lock(&daemon->mux);
+ if ((daemon->flags & ECRYPTFS_DAEMON_IN_READ)
+ || (daemon->flags & ECRYPTFS_DAEMON_IN_POLL)) {
+ rc = -EBUSY;
+ mutex_unlock(&daemon->mux);
+ goto out;
+ }
+ list_for_each_entry_safe(msg_ctx, msg_ctx_tmp,
+ &daemon->msg_ctx_out_queue, daemon_out_list) {
+ list_del(&msg_ctx->daemon_out_list);
+ daemon->num_queued_msg_ctx--;
+ printk(KERN_WARNING "%s: Warning: dropping message that is in "
+ "the out queue of a dying daemon\n", __func__);
+ ecryptfs_msg_ctx_alloc_to_free(msg_ctx);
+ }
+ hlist_del(&daemon->euid_chain);
+ mutex_unlock(&daemon->mux);
+ kzfree(daemon);
+out:
+ return rc;
+}
+
+/**
+ * ecryptfs_process_reponse
+ * @msg: The ecryptfs message received; the caller should sanity check
+ * msg->data_len and free the memory
+ * @seq: The sequence number of the message; must match the sequence
+ * number for the existing message context waiting for this
+ * response
+ *
+ * Processes a response message after sending an operation request to
+ * userspace. Some other process is awaiting this response. Before
+ * sending out its first communications, the other process allocated a
+ * msg_ctx from the ecryptfs_msg_ctx_arr at a particular index. The
+ * response message contains this index so that we can copy over the
+ * response message into the msg_ctx that the process holds a
+ * reference to. The other process is going to wake up, check to see
+ * that msg_ctx->state == ECRYPTFS_MSG_CTX_STATE_DONE, and then
+ * proceed to read off and process the response message. Returns zero
+ * upon delivery to desired context element; non-zero upon delivery
+ * failure or error.
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+int ecryptfs_process_response(struct ecryptfs_daemon *daemon,
+ struct ecryptfs_message *msg, u32 seq)
+{
+ struct ecryptfs_msg_ctx *msg_ctx;
+ size_t msg_size;
+ int rc;
+
+ if (msg->index >= ecryptfs_message_buf_len) {
+ rc = -EINVAL;
+ printk(KERN_ERR "%s: Attempt to reference "
+ "context buffer at index [%d]; maximum "
+ "allowable is [%d]\n", __func__, msg->index,
+ (ecryptfs_message_buf_len - 1));
+ goto out;
+ }
+ msg_ctx = &ecryptfs_msg_ctx_arr[msg->index];
+ mutex_lock(&msg_ctx->mux);
+ if (msg_ctx->state != ECRYPTFS_MSG_CTX_STATE_PENDING) {
+ rc = -EINVAL;
+ printk(KERN_WARNING "%s: Desired context element is not "
+ "pending a response\n", __func__);
+ goto unlock;
+ } else if (msg_ctx->counter != seq) {
+ rc = -EINVAL;
+ printk(KERN_WARNING "%s: Invalid message sequence; "
+ "expected [%d]; received [%d]\n", __func__,
+ msg_ctx->counter, seq);
+ goto unlock;
+ }
+ msg_size = (sizeof(*msg) + msg->data_len);
+ msg_ctx->msg = kmemdup(msg, msg_size, GFP_KERNEL);
+ if (!msg_ctx->msg) {
+ rc = -ENOMEM;
+ goto unlock;
+ }
+ msg_ctx->state = ECRYPTFS_MSG_CTX_STATE_DONE;
+ wake_up_process(msg_ctx->task);
+ rc = 0;
+unlock:
+ mutex_unlock(&msg_ctx->mux);
+out:
+ return rc;
+}
+
+/**
+ * ecryptfs_send_message_locked
+ * @data: The data to send
+ * @data_len: The length of data
+ * @msg_ctx: The message context allocated for the send
+ *
+ * Must be called with ecryptfs_daemon_hash_mux held.
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+static int
+ecryptfs_send_message_locked(char *data, int data_len, u8 msg_type,
+ struct ecryptfs_msg_ctx **msg_ctx)
+{
+ struct ecryptfs_daemon *daemon;
+ int rc;
+
+ rc = ecryptfs_find_daemon_by_euid(&daemon);
+ if (rc) {
+ rc = -ENOTCONN;
+ goto out;
+ }
+ mutex_lock(&ecryptfs_msg_ctx_lists_mux);
+ rc = ecryptfs_acquire_free_msg_ctx(msg_ctx);
+ if (rc) {
+ mutex_unlock(&ecryptfs_msg_ctx_lists_mux);
+ printk(KERN_WARNING "%s: Could not claim a free "
+ "context element\n", __func__);
+ goto out;
+ }
+ ecryptfs_msg_ctx_free_to_alloc(*msg_ctx);
+ mutex_unlock(&(*msg_ctx)->mux);
+ mutex_unlock(&ecryptfs_msg_ctx_lists_mux);
+ rc = ecryptfs_send_miscdev(data, data_len, *msg_ctx, msg_type, 0,
+ daemon);
+ if (rc)
+ printk(KERN_ERR "%s: Error attempting to send message to "
+ "userspace daemon; rc = [%d]\n", __func__, rc);
+out:
+ return rc;
+}
+
+/**
+ * ecryptfs_send_message
+ * @data: The data to send
+ * @data_len: The length of data
+ * @msg_ctx: The message context allocated for the send
+ *
+ * Grabs ecryptfs_daemon_hash_mux.
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+int ecryptfs_send_message(char *data, int data_len,
+ struct ecryptfs_msg_ctx **msg_ctx)
+{
+ int rc;
+
+ mutex_lock(&ecryptfs_daemon_hash_mux);
+ rc = ecryptfs_send_message_locked(data, data_len, ECRYPTFS_MSG_REQUEST,
+ msg_ctx);
+ mutex_unlock(&ecryptfs_daemon_hash_mux);
+ return rc;
+}
+
+/**
+ * ecryptfs_wait_for_response
+ * @msg_ctx: The context that was assigned when sending a message
+ * @msg: The incoming message from userspace; not set if rc != 0
+ *
+ * Sleeps until awaken by ecryptfs_receive_message or until the amount
+ * of time exceeds ecryptfs_message_wait_timeout. If zero is
+ * returned, msg will point to a valid message from userspace; a
+ * non-zero value is returned upon failure to receive a message or an
+ * error occurs. Callee must free @msg on success.
+ */
+int ecryptfs_wait_for_response(struct ecryptfs_msg_ctx *msg_ctx,
+ struct ecryptfs_message **msg)
+{
+ signed long timeout = ecryptfs_message_wait_timeout * HZ;
+ int rc = 0;
+
+sleep:
+ timeout = schedule_timeout_interruptible(timeout);
+ mutex_lock(&ecryptfs_msg_ctx_lists_mux);
+ mutex_lock(&msg_ctx->mux);
+ if (msg_ctx->state != ECRYPTFS_MSG_CTX_STATE_DONE) {
+ if (timeout) {
+ mutex_unlock(&msg_ctx->mux);
+ mutex_unlock(&ecryptfs_msg_ctx_lists_mux);
+ goto sleep;
+ }
+ rc = -ENOMSG;
+ } else {
+ *msg = msg_ctx->msg;
+ msg_ctx->msg = NULL;
+ }
+ ecryptfs_msg_ctx_alloc_to_free(msg_ctx);
+ mutex_unlock(&msg_ctx->mux);
+ mutex_unlock(&ecryptfs_msg_ctx_lists_mux);
+ return rc;
+}
+
+int __init ecryptfs_init_messaging(void)
+{
+ int i;
+ int rc = 0;
+
+ if (ecryptfs_number_of_users > ECRYPTFS_MAX_NUM_USERS) {
+ ecryptfs_number_of_users = ECRYPTFS_MAX_NUM_USERS;
+ printk(KERN_WARNING "%s: Specified number of users is "
+ "too large, defaulting to [%d] users\n", __func__,
+ ecryptfs_number_of_users);
+ }
+ mutex_init(&ecryptfs_daemon_hash_mux);
+ mutex_lock(&ecryptfs_daemon_hash_mux);
+ ecryptfs_hash_bits = 1;
+ while (ecryptfs_number_of_users >> ecryptfs_hash_bits)
+ ecryptfs_hash_bits++;
+ ecryptfs_daemon_hash = kmalloc((sizeof(struct hlist_head)
+ * (1 << ecryptfs_hash_bits)),
+ GFP_KERNEL);
+ if (!ecryptfs_daemon_hash) {
+ rc = -ENOMEM;
+ mutex_unlock(&ecryptfs_daemon_hash_mux);
+ goto out;
+ }
+ for (i = 0; i < (1 << ecryptfs_hash_bits); i++)
+ INIT_HLIST_HEAD(&ecryptfs_daemon_hash[i]);
+ mutex_unlock(&ecryptfs_daemon_hash_mux);
+ ecryptfs_msg_ctx_arr = kmalloc((sizeof(struct ecryptfs_msg_ctx)
+ * ecryptfs_message_buf_len),
+ GFP_KERNEL);
+ if (!ecryptfs_msg_ctx_arr) {
+ rc = -ENOMEM;
+ goto out;
+ }
+ mutex_init(&ecryptfs_msg_ctx_lists_mux);
+ mutex_lock(&ecryptfs_msg_ctx_lists_mux);
+ ecryptfs_msg_counter = 0;
+ for (i = 0; i < ecryptfs_message_buf_len; i++) {
+ INIT_LIST_HEAD(&ecryptfs_msg_ctx_arr[i].node);
+ INIT_LIST_HEAD(&ecryptfs_msg_ctx_arr[i].daemon_out_list);
+ mutex_init(&ecryptfs_msg_ctx_arr[i].mux);
+ mutex_lock(&ecryptfs_msg_ctx_arr[i].mux);
+ ecryptfs_msg_ctx_arr[i].index = i;
+ ecryptfs_msg_ctx_arr[i].state = ECRYPTFS_MSG_CTX_STATE_FREE;
+ ecryptfs_msg_ctx_arr[i].counter = 0;
+ ecryptfs_msg_ctx_arr[i].task = NULL;
+ ecryptfs_msg_ctx_arr[i].msg = NULL;
+ list_add_tail(&ecryptfs_msg_ctx_arr[i].node,
+ &ecryptfs_msg_ctx_free_list);
+ mutex_unlock(&ecryptfs_msg_ctx_arr[i].mux);
+ }
+ mutex_unlock(&ecryptfs_msg_ctx_lists_mux);
+ rc = ecryptfs_init_ecryptfs_miscdev();
+ if (rc)
+ ecryptfs_release_messaging();
+out:
+ return rc;
+}
+
+void ecryptfs_release_messaging(void)
+{
+ if (ecryptfs_msg_ctx_arr) {
+ int i;
+
+ mutex_lock(&ecryptfs_msg_ctx_lists_mux);
+ for (i = 0; i < ecryptfs_message_buf_len; i++) {
+ mutex_lock(&ecryptfs_msg_ctx_arr[i].mux);
+ kfree(ecryptfs_msg_ctx_arr[i].msg);
+ mutex_unlock(&ecryptfs_msg_ctx_arr[i].mux);
+ }
+ kfree(ecryptfs_msg_ctx_arr);
+ mutex_unlock(&ecryptfs_msg_ctx_lists_mux);
+ }
+ if (ecryptfs_daemon_hash) {
+ struct ecryptfs_daemon *daemon;
+ struct hlist_node *n;
+ int i;
+
+ mutex_lock(&ecryptfs_daemon_hash_mux);
+ for (i = 0; i < (1 << ecryptfs_hash_bits); i++) {
+ int rc;
+
+ hlist_for_each_entry_safe(daemon, n,
+ &ecryptfs_daemon_hash[i],
+ euid_chain) {
+ rc = ecryptfs_exorcise_daemon(daemon);
+ if (rc)
+ printk(KERN_ERR "%s: Error whilst "
+ "attempting to destroy daemon; "
+ "rc = [%d]. Dazed and confused, "
+ "but trying to continue.\n",
+ __func__, rc);
+ }
+ }
+ kfree(ecryptfs_daemon_hash);
+ mutex_unlock(&ecryptfs_daemon_hash_mux);
+ }
+ ecryptfs_destroy_ecryptfs_miscdev();
+ return;
+}
diff --git a/fs/ecryptfs/miscdev.c b/fs/ecryptfs/miscdev.c
new file mode 100644
index 0000000..2d1158e
--- /dev/null
+++ b/fs/ecryptfs/miscdev.c
@@ -0,0 +1,507 @@
+/**
+ * eCryptfs: Linux filesystem encryption layer
+ *
+ * Copyright (C) 2008 International Business Machines Corp.
+ * Author(s): Michael A. Halcrow <mhalcrow@us.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version
+ * 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ */
+
+#include <linux/fs.h>
+#include <linux/hash.h>
+#include <linux/random.h>
+#include <linux/miscdevice.h>
+#include <linux/poll.h>
+#include <linux/slab.h>
+#include <linux/wait.h>
+#include <linux/module.h>
+#include "ecryptfs_kernel.h"
+
+static atomic_t ecryptfs_num_miscdev_opens;
+
+/**
+ * ecryptfs_miscdev_poll
+ * @file: dev file
+ * @pt: dev poll table (ignored)
+ *
+ * Returns the poll mask
+ */
+static __poll_t
+ecryptfs_miscdev_poll(struct file *file, poll_table *pt)
+{
+ struct ecryptfs_daemon *daemon = file->private_data;
+ __poll_t mask = 0;
+
+ mutex_lock(&daemon->mux);
+ if (daemon->flags & ECRYPTFS_DAEMON_ZOMBIE) {
+ printk(KERN_WARNING "%s: Attempt to poll on zombified "
+ "daemon\n", __func__);
+ goto out_unlock_daemon;
+ }
+ if (daemon->flags & ECRYPTFS_DAEMON_IN_READ)
+ goto out_unlock_daemon;
+ if (daemon->flags & ECRYPTFS_DAEMON_IN_POLL)
+ goto out_unlock_daemon;
+ daemon->flags |= ECRYPTFS_DAEMON_IN_POLL;
+ mutex_unlock(&daemon->mux);
+ poll_wait(file, &daemon->wait, pt);
+ mutex_lock(&daemon->mux);
+ if (!list_empty(&daemon->msg_ctx_out_queue))
+ mask |= EPOLLIN | EPOLLRDNORM;
+out_unlock_daemon:
+ daemon->flags &= ~ECRYPTFS_DAEMON_IN_POLL;
+ mutex_unlock(&daemon->mux);
+ return mask;
+}
+
+/**
+ * ecryptfs_miscdev_open
+ * @inode: inode of miscdev handle (ignored)
+ * @file: file for miscdev handle
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+static int
+ecryptfs_miscdev_open(struct inode *inode, struct file *file)
+{
+ struct ecryptfs_daemon *daemon = NULL;
+ int rc;
+
+ mutex_lock(&ecryptfs_daemon_hash_mux);
+ rc = ecryptfs_find_daemon_by_euid(&daemon);
+ if (!rc) {
+ rc = -EINVAL;
+ goto out_unlock_daemon_list;
+ }
+ rc = ecryptfs_spawn_daemon(&daemon, file);
+ if (rc) {
+ printk(KERN_ERR "%s: Error attempting to spawn daemon; "
+ "rc = [%d]\n", __func__, rc);
+ goto out_unlock_daemon_list;
+ }
+ mutex_lock(&daemon->mux);
+ if (daemon->flags & ECRYPTFS_DAEMON_MISCDEV_OPEN) {
+ rc = -EBUSY;
+ goto out_unlock_daemon;
+ }
+ daemon->flags |= ECRYPTFS_DAEMON_MISCDEV_OPEN;
+ file->private_data = daemon;
+ atomic_inc(&ecryptfs_num_miscdev_opens);
+out_unlock_daemon:
+ mutex_unlock(&daemon->mux);
+out_unlock_daemon_list:
+ mutex_unlock(&ecryptfs_daemon_hash_mux);
+ return rc;
+}
+
+/**
+ * ecryptfs_miscdev_release
+ * @inode: inode of fs/ecryptfs/euid handle (ignored)
+ * @file: file for fs/ecryptfs/euid handle
+ *
+ * This keeps the daemon registered until the daemon sends another
+ * ioctl to fs/ecryptfs/ctl or until the kernel module unregisters.
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+static int
+ecryptfs_miscdev_release(struct inode *inode, struct file *file)
+{
+ struct ecryptfs_daemon *daemon = file->private_data;
+ int rc;
+
+ mutex_lock(&daemon->mux);
+ BUG_ON(!(daemon->flags & ECRYPTFS_DAEMON_MISCDEV_OPEN));
+ daemon->flags &= ~ECRYPTFS_DAEMON_MISCDEV_OPEN;
+ atomic_dec(&ecryptfs_num_miscdev_opens);
+ mutex_unlock(&daemon->mux);
+
+ mutex_lock(&ecryptfs_daemon_hash_mux);
+ rc = ecryptfs_exorcise_daemon(daemon);
+ mutex_unlock(&ecryptfs_daemon_hash_mux);
+ if (rc) {
+ printk(KERN_CRIT "%s: Fatal error whilst attempting to "
+ "shut down daemon; rc = [%d]. Please report this "
+ "bug.\n", __func__, rc);
+ BUG();
+ }
+ return rc;
+}
+
+/**
+ * ecryptfs_send_miscdev
+ * @data: Data to send to daemon; may be NULL
+ * @data_size: Amount of data to send to daemon
+ * @msg_ctx: Message context, which is used to handle the reply. If
+ * this is NULL, then we do not expect a reply.
+ * @msg_type: Type of message
+ * @msg_flags: Flags for message
+ * @daemon: eCryptfs daemon object
+ *
+ * Add msg_ctx to queue and then, if it exists, notify the blocked
+ * miscdevess about the data being available. Must be called with
+ * ecryptfs_daemon_hash_mux held.
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+int ecryptfs_send_miscdev(char *data, size_t data_size,
+ struct ecryptfs_msg_ctx *msg_ctx, u8 msg_type,
+ u16 msg_flags, struct ecryptfs_daemon *daemon)
+{
+ struct ecryptfs_message *msg;
+
+ msg = kmalloc((sizeof(*msg) + data_size), GFP_KERNEL);
+ if (!msg)
+ return -ENOMEM;
+
+ mutex_lock(&msg_ctx->mux);
+ msg_ctx->msg = msg;
+ msg_ctx->msg->index = msg_ctx->index;
+ msg_ctx->msg->data_len = data_size;
+ msg_ctx->type = msg_type;
+ memcpy(msg_ctx->msg->data, data, data_size);
+ msg_ctx->msg_size = (sizeof(*msg_ctx->msg) + data_size);
+ list_add_tail(&msg_ctx->daemon_out_list, &daemon->msg_ctx_out_queue);
+ mutex_unlock(&msg_ctx->mux);
+
+ mutex_lock(&daemon->mux);
+ daemon->num_queued_msg_ctx++;
+ wake_up_interruptible(&daemon->wait);
+ mutex_unlock(&daemon->mux);
+
+ return 0;
+}
+
+/*
+ * miscdevfs packet format:
+ * Octet 0: Type
+ * Octets 1-4: network byte order msg_ctx->counter
+ * Octets 5-N0: Size of struct ecryptfs_message to follow
+ * Octets N0-N1: struct ecryptfs_message (including data)
+ *
+ * Octets 5-N1 not written if the packet type does not include a message
+ */
+#define PKT_TYPE_SIZE 1
+#define PKT_CTR_SIZE 4
+#define MIN_NON_MSG_PKT_SIZE (PKT_TYPE_SIZE + PKT_CTR_SIZE)
+#define MIN_MSG_PKT_SIZE (PKT_TYPE_SIZE + PKT_CTR_SIZE \
+ + ECRYPTFS_MIN_PKT_LEN_SIZE)
+/* 4 + ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES comes from tag 65 packet format */
+#define MAX_MSG_PKT_SIZE (PKT_TYPE_SIZE + PKT_CTR_SIZE \
+ + ECRYPTFS_MAX_PKT_LEN_SIZE \
+ + sizeof(struct ecryptfs_message) \
+ + 4 + ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES)
+#define PKT_TYPE_OFFSET 0
+#define PKT_CTR_OFFSET PKT_TYPE_SIZE
+#define PKT_LEN_OFFSET (PKT_TYPE_SIZE + PKT_CTR_SIZE)
+
+/**
+ * ecryptfs_miscdev_read - format and send message from queue
+ * @file: miscdevfs handle
+ * @buf: User buffer into which to copy the next message on the daemon queue
+ * @count: Amount of space available in @buf
+ * @ppos: Offset in file (ignored)
+ *
+ * Pulls the most recent message from the daemon queue, formats it for
+ * being sent via a miscdevfs handle, and copies it into @buf
+ *
+ * Returns the number of bytes copied into the user buffer
+ */
+static ssize_t
+ecryptfs_miscdev_read(struct file *file, char __user *buf, size_t count,
+ loff_t *ppos)
+{
+ struct ecryptfs_daemon *daemon = file->private_data;
+ struct ecryptfs_msg_ctx *msg_ctx;
+ size_t packet_length_size;
+ char packet_length[ECRYPTFS_MAX_PKT_LEN_SIZE];
+ size_t i;
+ size_t total_length;
+ int rc;
+
+ mutex_lock(&daemon->mux);
+ if (daemon->flags & ECRYPTFS_DAEMON_ZOMBIE) {
+ rc = 0;
+ printk(KERN_WARNING "%s: Attempt to read from zombified "
+ "daemon\n", __func__);
+ goto out_unlock_daemon;
+ }
+ if (daemon->flags & ECRYPTFS_DAEMON_IN_READ) {
+ rc = 0;
+ goto out_unlock_daemon;
+ }
+ /* This daemon will not go away so long as this flag is set */
+ daemon->flags |= ECRYPTFS_DAEMON_IN_READ;
+check_list:
+ if (list_empty(&daemon->msg_ctx_out_queue)) {
+ mutex_unlock(&daemon->mux);
+ rc = wait_event_interruptible(
+ daemon->wait, !list_empty(&daemon->msg_ctx_out_queue));
+ mutex_lock(&daemon->mux);
+ if (rc < 0) {
+ rc = 0;
+ goto out_unlock_daemon;
+ }
+ }
+ if (daemon->flags & ECRYPTFS_DAEMON_ZOMBIE) {
+ rc = 0;
+ goto out_unlock_daemon;
+ }
+ if (list_empty(&daemon->msg_ctx_out_queue)) {
+ /* Something else jumped in since the
+ * wait_event_interruptable() and removed the
+ * message from the queue; try again */
+ goto check_list;
+ }
+ msg_ctx = list_first_entry(&daemon->msg_ctx_out_queue,
+ struct ecryptfs_msg_ctx, daemon_out_list);
+ BUG_ON(!msg_ctx);
+ mutex_lock(&msg_ctx->mux);
+ if (msg_ctx->msg) {
+ rc = ecryptfs_write_packet_length(packet_length,
+ msg_ctx->msg_size,
+ &packet_length_size);
+ if (rc) {
+ rc = 0;
+ printk(KERN_WARNING "%s: Error writing packet length; "
+ "rc = [%d]\n", __func__, rc);
+ goto out_unlock_msg_ctx;
+ }
+ } else {
+ packet_length_size = 0;
+ msg_ctx->msg_size = 0;
+ }
+ total_length = (PKT_TYPE_SIZE + PKT_CTR_SIZE + packet_length_size
+ + msg_ctx->msg_size);
+ if (count < total_length) {
+ rc = 0;
+ printk(KERN_WARNING "%s: Only given user buffer of "
+ "size [%zd], but we need [%zd] to read the "
+ "pending message\n", __func__, count, total_length);
+ goto out_unlock_msg_ctx;
+ }
+ rc = -EFAULT;
+ if (put_user(msg_ctx->type, buf))
+ goto out_unlock_msg_ctx;
+ if (put_user(cpu_to_be32(msg_ctx->counter),
+ (__be32 __user *)(&buf[PKT_CTR_OFFSET])))
+ goto out_unlock_msg_ctx;
+ i = PKT_TYPE_SIZE + PKT_CTR_SIZE;
+ if (msg_ctx->msg) {
+ if (copy_to_user(&buf[i], packet_length, packet_length_size))
+ goto out_unlock_msg_ctx;
+ i += packet_length_size;
+ if (copy_to_user(&buf[i], msg_ctx->msg, msg_ctx->msg_size))
+ goto out_unlock_msg_ctx;
+ i += msg_ctx->msg_size;
+ }
+ rc = i;
+ list_del(&msg_ctx->daemon_out_list);
+ kfree(msg_ctx->msg);
+ msg_ctx->msg = NULL;
+ /* We do not expect a reply from the userspace daemon for any
+ * message type other than ECRYPTFS_MSG_REQUEST */
+ if (msg_ctx->type != ECRYPTFS_MSG_REQUEST)
+ ecryptfs_msg_ctx_alloc_to_free(msg_ctx);
+out_unlock_msg_ctx:
+ mutex_unlock(&msg_ctx->mux);
+out_unlock_daemon:
+ daemon->flags &= ~ECRYPTFS_DAEMON_IN_READ;
+ mutex_unlock(&daemon->mux);
+ return rc;
+}
+
+/**
+ * ecryptfs_miscdev_response - miscdevess response to message previously sent to daemon
+ * @data: Bytes comprising struct ecryptfs_message
+ * @data_size: sizeof(struct ecryptfs_message) + data len
+ * @seq: Sequence number for miscdev response packet
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+static int ecryptfs_miscdev_response(struct ecryptfs_daemon *daemon, char *data,
+ size_t data_size, u32 seq)
+{
+ struct ecryptfs_message *msg = (struct ecryptfs_message *)data;
+ int rc;
+
+ if ((sizeof(*msg) + msg->data_len) != data_size) {
+ printk(KERN_WARNING "%s: (sizeof(*msg) + msg->data_len) = "
+ "[%zd]; data_size = [%zd]. Invalid packet.\n", __func__,
+ (sizeof(*msg) + msg->data_len), data_size);
+ rc = -EINVAL;
+ goto out;
+ }
+ rc = ecryptfs_process_response(daemon, msg, seq);
+ if (rc)
+ printk(KERN_ERR
+ "Error processing response message; rc = [%d]\n", rc);
+out:
+ return rc;
+}
+
+/**
+ * ecryptfs_miscdev_write - handle write to daemon miscdev handle
+ * @file: File for misc dev handle
+ * @buf: Buffer containing user data
+ * @count: Amount of data in @buf
+ * @ppos: Pointer to offset in file (ignored)
+ *
+ * Returns the number of bytes read from @buf
+ */
+static ssize_t
+ecryptfs_miscdev_write(struct file *file, const char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ __be32 counter_nbo;
+ u32 seq;
+ size_t packet_size, packet_size_length;
+ char *data;
+ unsigned char packet_size_peek[ECRYPTFS_MAX_PKT_LEN_SIZE];
+ ssize_t rc;
+
+ if (count == 0) {
+ return 0;
+ } else if (count == MIN_NON_MSG_PKT_SIZE) {
+ /* Likely a harmless MSG_HELO or MSG_QUIT - no packet length */
+ goto memdup;
+ } else if (count < MIN_MSG_PKT_SIZE || count > MAX_MSG_PKT_SIZE) {
+ printk(KERN_WARNING "%s: Acceptable packet size range is "
+ "[%d-%zu], but amount of data written is [%zu].\n",
+ __func__, MIN_MSG_PKT_SIZE, MAX_MSG_PKT_SIZE, count);
+ return -EINVAL;
+ }
+
+ if (copy_from_user(packet_size_peek, &buf[PKT_LEN_OFFSET],
+ sizeof(packet_size_peek))) {
+ printk(KERN_WARNING "%s: Error while inspecting packet size\n",
+ __func__);
+ return -EFAULT;
+ }
+
+ rc = ecryptfs_parse_packet_length(packet_size_peek, &packet_size,
+ &packet_size_length);
+ if (rc) {
+ printk(KERN_WARNING "%s: Error parsing packet length; "
+ "rc = [%zd]\n", __func__, rc);
+ return rc;
+ }
+
+ if ((PKT_TYPE_SIZE + PKT_CTR_SIZE + packet_size_length + packet_size)
+ != count) {
+ printk(KERN_WARNING "%s: Invalid packet size [%zu]\n", __func__,
+ packet_size);
+ return -EINVAL;
+ }
+
+memdup:
+ data = memdup_user(buf, count);
+ if (IS_ERR(data)) {
+ printk(KERN_ERR "%s: memdup_user returned error [%ld]\n",
+ __func__, PTR_ERR(data));
+ return PTR_ERR(data);
+ }
+ switch (data[PKT_TYPE_OFFSET]) {
+ case ECRYPTFS_MSG_RESPONSE:
+ if (count < (MIN_MSG_PKT_SIZE
+ + sizeof(struct ecryptfs_message))) {
+ printk(KERN_WARNING "%s: Minimum acceptable packet "
+ "size is [%zd], but amount of data written is "
+ "only [%zd]. Discarding response packet.\n",
+ __func__,
+ (MIN_MSG_PKT_SIZE
+ + sizeof(struct ecryptfs_message)), count);
+ rc = -EINVAL;
+ goto out_free;
+ }
+ memcpy(&counter_nbo, &data[PKT_CTR_OFFSET], PKT_CTR_SIZE);
+ seq = be32_to_cpu(counter_nbo);
+ rc = ecryptfs_miscdev_response(file->private_data,
+ &data[PKT_LEN_OFFSET + packet_size_length],
+ packet_size, seq);
+ if (rc) {
+ printk(KERN_WARNING "%s: Failed to deliver miscdev "
+ "response to requesting operation; rc = [%zd]\n",
+ __func__, rc);
+ goto out_free;
+ }
+ break;
+ case ECRYPTFS_MSG_HELO:
+ case ECRYPTFS_MSG_QUIT:
+ break;
+ default:
+ ecryptfs_printk(KERN_WARNING, "Dropping miscdev "
+ "message of unrecognized type [%d]\n",
+ data[0]);
+ rc = -EINVAL;
+ goto out_free;
+ }
+ rc = count;
+out_free:
+ kfree(data);
+ return rc;
+}
+
+
+static const struct file_operations ecryptfs_miscdev_fops = {
+ .owner = THIS_MODULE,
+ .open = ecryptfs_miscdev_open,
+ .poll = ecryptfs_miscdev_poll,
+ .read = ecryptfs_miscdev_read,
+ .write = ecryptfs_miscdev_write,
+ .release = ecryptfs_miscdev_release,
+ .llseek = noop_llseek,
+};
+
+static struct miscdevice ecryptfs_miscdev = {
+ .minor = MISC_DYNAMIC_MINOR,
+ .name = "ecryptfs",
+ .fops = &ecryptfs_miscdev_fops
+};
+
+/**
+ * ecryptfs_init_ecryptfs_miscdev
+ *
+ * Messages sent to the userspace daemon from the kernel are placed on
+ * a queue associated with the daemon. The next read against the
+ * miscdev handle by that daemon will return the oldest message placed
+ * on the message queue for the daemon.
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+int __init ecryptfs_init_ecryptfs_miscdev(void)
+{
+ int rc;
+
+ atomic_set(&ecryptfs_num_miscdev_opens, 0);
+ rc = misc_register(&ecryptfs_miscdev);
+ if (rc)
+ printk(KERN_ERR "%s: Failed to register miscellaneous device "
+ "for communications with userspace daemons; rc = [%d]\n",
+ __func__, rc);
+ return rc;
+}
+
+/**
+ * ecryptfs_destroy_ecryptfs_miscdev
+ *
+ * All of the daemons must be exorcised prior to calling this
+ * function.
+ */
+void ecryptfs_destroy_ecryptfs_miscdev(void)
+{
+ BUG_ON(atomic_read(&ecryptfs_num_miscdev_opens) != 0);
+ misc_deregister(&ecryptfs_miscdev);
+}
diff --git a/fs/ecryptfs/mmap.c b/fs/ecryptfs/mmap.c
new file mode 100644
index 0000000..cdf358b
--- /dev/null
+++ b/fs/ecryptfs/mmap.c
@@ -0,0 +1,559 @@
+/**
+ * eCryptfs: Linux filesystem encryption layer
+ * This is where eCryptfs coordinates the symmetric encryption and
+ * decryption of the file data as it passes between the lower
+ * encrypted file and the upper decrypted file.
+ *
+ * Copyright (C) 1997-2003 Erez Zadok
+ * Copyright (C) 2001-2003 Stony Brook University
+ * Copyright (C) 2004-2007 International Business Machines Corp.
+ * Author(s): Michael A. Halcrow <mahalcro@us.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ */
+
+#include <linux/pagemap.h>
+#include <linux/writeback.h>
+#include <linux/page-flags.h>
+#include <linux/mount.h>
+#include <linux/file.h>
+#include <linux/scatterlist.h>
+#include <linux/slab.h>
+#include <linux/xattr.h>
+#include <asm/unaligned.h>
+#include "ecryptfs_kernel.h"
+
+/**
+ * ecryptfs_get_locked_page
+ *
+ * Get one page from cache or lower f/s, return error otherwise.
+ *
+ * Returns locked and up-to-date page (if ok), with increased
+ * refcnt.
+ */
+struct page *ecryptfs_get_locked_page(struct inode *inode, loff_t index)
+{
+ struct page *page = read_mapping_page(inode->i_mapping, index, NULL);
+ if (!IS_ERR(page))
+ lock_page(page);
+ return page;
+}
+
+/**
+ * ecryptfs_writepage
+ * @page: Page that is locked before this call is made
+ *
+ * Returns zero on success; non-zero otherwise
+ *
+ * This is where we encrypt the data and pass the encrypted data to
+ * the lower filesystem. In OpenPGP-compatible mode, we operate on
+ * entire underlying packets.
+ */
+static int ecryptfs_writepage(struct page *page, struct writeback_control *wbc)
+{
+ int rc;
+
+ rc = ecryptfs_encrypt_page(page);
+ if (rc) {
+ ecryptfs_printk(KERN_WARNING, "Error encrypting "
+ "page (upper index [0x%.16lx])\n", page->index);
+ ClearPageUptodate(page);
+ goto out;
+ }
+ SetPageUptodate(page);
+out:
+ unlock_page(page);
+ return rc;
+}
+
+static void strip_xattr_flag(char *page_virt,
+ struct ecryptfs_crypt_stat *crypt_stat)
+{
+ if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR) {
+ size_t written;
+
+ crypt_stat->flags &= ~ECRYPTFS_METADATA_IN_XATTR;
+ ecryptfs_write_crypt_stat_flags(page_virt, crypt_stat,
+ &written);
+ crypt_stat->flags |= ECRYPTFS_METADATA_IN_XATTR;
+ }
+}
+
+/**
+ * Header Extent:
+ * Octets 0-7: Unencrypted file size (big-endian)
+ * Octets 8-15: eCryptfs special marker
+ * Octets 16-19: Flags
+ * Octet 16: File format version number (between 0 and 255)
+ * Octets 17-18: Reserved
+ * Octet 19: Bit 1 (lsb): Reserved
+ * Bit 2: Encrypted?
+ * Bits 3-8: Reserved
+ * Octets 20-23: Header extent size (big-endian)
+ * Octets 24-25: Number of header extents at front of file
+ * (big-endian)
+ * Octet 26: Begin RFC 2440 authentication token packet set
+ */
+
+/**
+ * ecryptfs_copy_up_encrypted_with_header
+ * @page: Sort of a ``virtual'' representation of the encrypted lower
+ * file. The actual lower file does not have the metadata in
+ * the header. This is locked.
+ * @crypt_stat: The eCryptfs inode's cryptographic context
+ *
+ * The ``view'' is the version of the file that userspace winds up
+ * seeing, with the header information inserted.
+ */
+static int
+ecryptfs_copy_up_encrypted_with_header(struct page *page,
+ struct ecryptfs_crypt_stat *crypt_stat)
+{
+ loff_t extent_num_in_page = 0;
+ loff_t num_extents_per_page = (PAGE_SIZE
+ / crypt_stat->extent_size);
+ int rc = 0;
+
+ while (extent_num_in_page < num_extents_per_page) {
+ loff_t view_extent_num = ((((loff_t)page->index)
+ * num_extents_per_page)
+ + extent_num_in_page);
+ size_t num_header_extents_at_front =
+ (crypt_stat->metadata_size / crypt_stat->extent_size);
+
+ if (view_extent_num < num_header_extents_at_front) {
+ /* This is a header extent */
+ char *page_virt;
+
+ page_virt = kmap_atomic(page);
+ memset(page_virt, 0, PAGE_SIZE);
+ /* TODO: Support more than one header extent */
+ if (view_extent_num == 0) {
+ size_t written;
+
+ rc = ecryptfs_read_xattr_region(
+ page_virt, page->mapping->host);
+ strip_xattr_flag(page_virt + 16, crypt_stat);
+ ecryptfs_write_header_metadata(page_virt + 20,
+ crypt_stat,
+ &written);
+ }
+ kunmap_atomic(page_virt);
+ flush_dcache_page(page);
+ if (rc) {
+ printk(KERN_ERR "%s: Error reading xattr "
+ "region; rc = [%d]\n", __func__, rc);
+ goto out;
+ }
+ } else {
+ /* This is an encrypted data extent */
+ loff_t lower_offset =
+ ((view_extent_num * crypt_stat->extent_size)
+ - crypt_stat->metadata_size);
+
+ rc = ecryptfs_read_lower_page_segment(
+ page, (lower_offset >> PAGE_SHIFT),
+ (lower_offset & ~PAGE_MASK),
+ crypt_stat->extent_size, page->mapping->host);
+ if (rc) {
+ printk(KERN_ERR "%s: Error attempting to read "
+ "extent at offset [%lld] in the lower "
+ "file; rc = [%d]\n", __func__,
+ lower_offset, rc);
+ goto out;
+ }
+ }
+ extent_num_in_page++;
+ }
+out:
+ return rc;
+}
+
+/**
+ * ecryptfs_readpage
+ * @file: An eCryptfs file
+ * @page: Page from eCryptfs inode mapping into which to stick the read data
+ *
+ * Read in a page, decrypting if necessary.
+ *
+ * Returns zero on success; non-zero on error.
+ */
+static int ecryptfs_readpage(struct file *file, struct page *page)
+{
+ struct ecryptfs_crypt_stat *crypt_stat =
+ &ecryptfs_inode_to_private(page->mapping->host)->crypt_stat;
+ int rc = 0;
+
+ if (!crypt_stat || !(crypt_stat->flags & ECRYPTFS_ENCRYPTED)) {
+ rc = ecryptfs_read_lower_page_segment(page, page->index, 0,
+ PAGE_SIZE,
+ page->mapping->host);
+ } else if (crypt_stat->flags & ECRYPTFS_VIEW_AS_ENCRYPTED) {
+ if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR) {
+ rc = ecryptfs_copy_up_encrypted_with_header(page,
+ crypt_stat);
+ if (rc) {
+ printk(KERN_ERR "%s: Error attempting to copy "
+ "the encrypted content from the lower "
+ "file whilst inserting the metadata "
+ "from the xattr into the header; rc = "
+ "[%d]\n", __func__, rc);
+ goto out;
+ }
+
+ } else {
+ rc = ecryptfs_read_lower_page_segment(
+ page, page->index, 0, PAGE_SIZE,
+ page->mapping->host);
+ if (rc) {
+ printk(KERN_ERR "Error reading page; rc = "
+ "[%d]\n", rc);
+ goto out;
+ }
+ }
+ } else {
+ rc = ecryptfs_decrypt_page(page);
+ if (rc) {
+ ecryptfs_printk(KERN_ERR, "Error decrypting page; "
+ "rc = [%d]\n", rc);
+ goto out;
+ }
+ }
+out:
+ if (rc)
+ ClearPageUptodate(page);
+ else
+ SetPageUptodate(page);
+ ecryptfs_printk(KERN_DEBUG, "Unlocking page with index = [0x%.16lx]\n",
+ page->index);
+ unlock_page(page);
+ return rc;
+}
+
+/**
+ * Called with lower inode mutex held.
+ */
+static int fill_zeros_to_end_of_page(struct page *page, unsigned int to)
+{
+ struct inode *inode = page->mapping->host;
+ int end_byte_in_page;
+
+ if ((i_size_read(inode) / PAGE_SIZE) != page->index)
+ goto out;
+ end_byte_in_page = i_size_read(inode) % PAGE_SIZE;
+ if (to > end_byte_in_page)
+ end_byte_in_page = to;
+ zero_user_segment(page, end_byte_in_page, PAGE_SIZE);
+out:
+ return 0;
+}
+
+/**
+ * ecryptfs_write_begin
+ * @file: The eCryptfs file
+ * @mapping: The eCryptfs object
+ * @pos: The file offset at which to start writing
+ * @len: Length of the write
+ * @flags: Various flags
+ * @pagep: Pointer to return the page
+ * @fsdata: Pointer to return fs data (unused)
+ *
+ * This function must zero any hole we create
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+static int ecryptfs_write_begin(struct file *file,
+ struct address_space *mapping,
+ loff_t pos, unsigned len, unsigned flags,
+ struct page **pagep, void **fsdata)
+{
+ pgoff_t index = pos >> PAGE_SHIFT;
+ struct page *page;
+ loff_t prev_page_end_size;
+ int rc = 0;
+
+ page = grab_cache_page_write_begin(mapping, index, flags);
+ if (!page)
+ return -ENOMEM;
+ *pagep = page;
+
+ prev_page_end_size = ((loff_t)index << PAGE_SHIFT);
+ if (!PageUptodate(page)) {
+ struct ecryptfs_crypt_stat *crypt_stat =
+ &ecryptfs_inode_to_private(mapping->host)->crypt_stat;
+
+ if (!(crypt_stat->flags & ECRYPTFS_ENCRYPTED)) {
+ rc = ecryptfs_read_lower_page_segment(
+ page, index, 0, PAGE_SIZE, mapping->host);
+ if (rc) {
+ printk(KERN_ERR "%s: Error attempting to read "
+ "lower page segment; rc = [%d]\n",
+ __func__, rc);
+ ClearPageUptodate(page);
+ goto out;
+ } else
+ SetPageUptodate(page);
+ } else if (crypt_stat->flags & ECRYPTFS_VIEW_AS_ENCRYPTED) {
+ if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR) {
+ rc = ecryptfs_copy_up_encrypted_with_header(
+ page, crypt_stat);
+ if (rc) {
+ printk(KERN_ERR "%s: Error attempting "
+ "to copy the encrypted content "
+ "from the lower file whilst "
+ "inserting the metadata from "
+ "the xattr into the header; rc "
+ "= [%d]\n", __func__, rc);
+ ClearPageUptodate(page);
+ goto out;
+ }
+ SetPageUptodate(page);
+ } else {
+ rc = ecryptfs_read_lower_page_segment(
+ page, index, 0, PAGE_SIZE,
+ mapping->host);
+ if (rc) {
+ printk(KERN_ERR "%s: Error reading "
+ "page; rc = [%d]\n",
+ __func__, rc);
+ ClearPageUptodate(page);
+ goto out;
+ }
+ SetPageUptodate(page);
+ }
+ } else {
+ if (prev_page_end_size
+ >= i_size_read(page->mapping->host)) {
+ zero_user(page, 0, PAGE_SIZE);
+ SetPageUptodate(page);
+ } else if (len < PAGE_SIZE) {
+ rc = ecryptfs_decrypt_page(page);
+ if (rc) {
+ printk(KERN_ERR "%s: Error decrypting "
+ "page at index [%ld]; "
+ "rc = [%d]\n",
+ __func__, page->index, rc);
+ ClearPageUptodate(page);
+ goto out;
+ }
+ SetPageUptodate(page);
+ }
+ }
+ }
+ /* If creating a page or more of holes, zero them out via truncate.
+ * Note, this will increase i_size. */
+ if (index != 0) {
+ if (prev_page_end_size > i_size_read(page->mapping->host)) {
+ rc = ecryptfs_truncate(file->f_path.dentry,
+ prev_page_end_size);
+ if (rc) {
+ printk(KERN_ERR "%s: Error on attempt to "
+ "truncate to (higher) offset [%lld];"
+ " rc = [%d]\n", __func__,
+ prev_page_end_size, rc);
+ goto out;
+ }
+ }
+ }
+ /* Writing to a new page, and creating a small hole from start
+ * of page? Zero it out. */
+ if ((i_size_read(mapping->host) == prev_page_end_size)
+ && (pos != 0))
+ zero_user(page, 0, PAGE_SIZE);
+out:
+ if (unlikely(rc)) {
+ unlock_page(page);
+ put_page(page);
+ *pagep = NULL;
+ }
+ return rc;
+}
+
+/**
+ * ecryptfs_write_inode_size_to_header
+ *
+ * Writes the lower file size to the first 8 bytes of the header.
+ *
+ * Returns zero on success; non-zero on error.
+ */
+static int ecryptfs_write_inode_size_to_header(struct inode *ecryptfs_inode)
+{
+ char *file_size_virt;
+ int rc;
+
+ file_size_virt = kmalloc(sizeof(u64), GFP_KERNEL);
+ if (!file_size_virt) {
+ rc = -ENOMEM;
+ goto out;
+ }
+ put_unaligned_be64(i_size_read(ecryptfs_inode), file_size_virt);
+ rc = ecryptfs_write_lower(ecryptfs_inode, file_size_virt, 0,
+ sizeof(u64));
+ kfree(file_size_virt);
+ if (rc < 0)
+ printk(KERN_ERR "%s: Error writing file size to header; "
+ "rc = [%d]\n", __func__, rc);
+ else
+ rc = 0;
+out:
+ return rc;
+}
+
+struct kmem_cache *ecryptfs_xattr_cache;
+
+static int ecryptfs_write_inode_size_to_xattr(struct inode *ecryptfs_inode)
+{
+ ssize_t size;
+ void *xattr_virt;
+ struct dentry *lower_dentry =
+ ecryptfs_inode_to_private(ecryptfs_inode)->lower_file->f_path.dentry;
+ struct inode *lower_inode = d_inode(lower_dentry);
+ int rc;
+
+ if (!(lower_inode->i_opflags & IOP_XATTR)) {
+ printk(KERN_WARNING
+ "No support for setting xattr in lower filesystem\n");
+ rc = -ENOSYS;
+ goto out;
+ }
+ xattr_virt = kmem_cache_alloc(ecryptfs_xattr_cache, GFP_KERNEL);
+ if (!xattr_virt) {
+ rc = -ENOMEM;
+ goto out;
+ }
+ inode_lock(lower_inode);
+ size = __vfs_getxattr(lower_dentry, lower_inode, ECRYPTFS_XATTR_NAME,
+ xattr_virt, PAGE_SIZE);
+ if (size < 0)
+ size = 8;
+ put_unaligned_be64(i_size_read(ecryptfs_inode), xattr_virt);
+ rc = __vfs_setxattr(lower_dentry, lower_inode, ECRYPTFS_XATTR_NAME,
+ xattr_virt, size, 0);
+ inode_unlock(lower_inode);
+ if (rc)
+ printk(KERN_ERR "Error whilst attempting to write inode size "
+ "to lower file xattr; rc = [%d]\n", rc);
+ kmem_cache_free(ecryptfs_xattr_cache, xattr_virt);
+out:
+ return rc;
+}
+
+int ecryptfs_write_inode_size_to_metadata(struct inode *ecryptfs_inode)
+{
+ struct ecryptfs_crypt_stat *crypt_stat;
+
+ crypt_stat = &ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat;
+ BUG_ON(!(crypt_stat->flags & ECRYPTFS_ENCRYPTED));
+ if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR)
+ return ecryptfs_write_inode_size_to_xattr(ecryptfs_inode);
+ else
+ return ecryptfs_write_inode_size_to_header(ecryptfs_inode);
+}
+
+/**
+ * ecryptfs_write_end
+ * @file: The eCryptfs file object
+ * @mapping: The eCryptfs object
+ * @pos: The file position
+ * @len: The length of the data (unused)
+ * @copied: The amount of data copied
+ * @page: The eCryptfs page
+ * @fsdata: The fsdata (unused)
+ */
+static int ecryptfs_write_end(struct file *file,
+ struct address_space *mapping,
+ loff_t pos, unsigned len, unsigned copied,
+ struct page *page, void *fsdata)
+{
+ pgoff_t index = pos >> PAGE_SHIFT;
+ unsigned from = pos & (PAGE_SIZE - 1);
+ unsigned to = from + copied;
+ struct inode *ecryptfs_inode = mapping->host;
+ struct ecryptfs_crypt_stat *crypt_stat =
+ &ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat;
+ int rc;
+
+ ecryptfs_printk(KERN_DEBUG, "Calling fill_zeros_to_end_of_page"
+ "(page w/ index = [0x%.16lx], to = [%d])\n", index, to);
+ if (!(crypt_stat->flags & ECRYPTFS_ENCRYPTED)) {
+ rc = ecryptfs_write_lower_page_segment(ecryptfs_inode, page, 0,
+ to);
+ if (!rc) {
+ rc = copied;
+ fsstack_copy_inode_size(ecryptfs_inode,
+ ecryptfs_inode_to_lower(ecryptfs_inode));
+ }
+ goto out;
+ }
+ if (!PageUptodate(page)) {
+ if (copied < PAGE_SIZE) {
+ rc = 0;
+ goto out;
+ }
+ SetPageUptodate(page);
+ }
+ /* Fills in zeros if 'to' goes beyond inode size */
+ rc = fill_zeros_to_end_of_page(page, to);
+ if (rc) {
+ ecryptfs_printk(KERN_WARNING, "Error attempting to fill "
+ "zeros in page with index = [0x%.16lx]\n", index);
+ goto out;
+ }
+ rc = ecryptfs_encrypt_page(page);
+ if (rc) {
+ ecryptfs_printk(KERN_WARNING, "Error encrypting page (upper "
+ "index [0x%.16lx])\n", index);
+ goto out;
+ }
+ if (pos + copied > i_size_read(ecryptfs_inode)) {
+ i_size_write(ecryptfs_inode, pos + copied);
+ ecryptfs_printk(KERN_DEBUG, "Expanded file size to "
+ "[0x%.16llx]\n",
+ (unsigned long long)i_size_read(ecryptfs_inode));
+ }
+ rc = ecryptfs_write_inode_size_to_metadata(ecryptfs_inode);
+ if (rc)
+ printk(KERN_ERR "Error writing inode size to metadata; "
+ "rc = [%d]\n", rc);
+ else
+ rc = copied;
+out:
+ unlock_page(page);
+ put_page(page);
+ return rc;
+}
+
+static sector_t ecryptfs_bmap(struct address_space *mapping, sector_t block)
+{
+ int rc = 0;
+ struct inode *inode;
+ struct inode *lower_inode;
+
+ inode = (struct inode *)mapping->host;
+ lower_inode = ecryptfs_inode_to_lower(inode);
+ if (lower_inode->i_mapping->a_ops->bmap)
+ rc = lower_inode->i_mapping->a_ops->bmap(lower_inode->i_mapping,
+ block);
+ return rc;
+}
+
+const struct address_space_operations ecryptfs_aops = {
+ .writepage = ecryptfs_writepage,
+ .readpage = ecryptfs_readpage,
+ .write_begin = ecryptfs_write_begin,
+ .write_end = ecryptfs_write_end,
+ .bmap = ecryptfs_bmap,
+};
diff --git a/fs/ecryptfs/read_write.c b/fs/ecryptfs/read_write.c
new file mode 100644
index 0000000..c596e7c
--- /dev/null
+++ b/fs/ecryptfs/read_write.c
@@ -0,0 +1,275 @@
+/**
+ * eCryptfs: Linux filesystem encryption layer
+ *
+ * Copyright (C) 2007 International Business Machines Corp.
+ * Author(s): Michael A. Halcrow <mahalcro@us.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ */
+
+#include <linux/fs.h>
+#include <linux/pagemap.h>
+#include <linux/sched/signal.h>
+
+#include "ecryptfs_kernel.h"
+
+/**
+ * ecryptfs_write_lower
+ * @ecryptfs_inode: The eCryptfs inode
+ * @data: Data to write
+ * @offset: Byte offset in the lower file to which to write the data
+ * @size: Number of bytes from @data to write at @offset in the lower
+ * file
+ *
+ * Write data to the lower file.
+ *
+ * Returns bytes written on success; less than zero on error
+ */
+int ecryptfs_write_lower(struct inode *ecryptfs_inode, char *data,
+ loff_t offset, size_t size)
+{
+ struct file *lower_file;
+ ssize_t rc;
+
+ lower_file = ecryptfs_inode_to_private(ecryptfs_inode)->lower_file;
+ if (!lower_file)
+ return -EIO;
+ rc = kernel_write(lower_file, data, size, &offset);
+ mark_inode_dirty_sync(ecryptfs_inode);
+ return rc;
+}
+
+/**
+ * ecryptfs_write_lower_page_segment
+ * @ecryptfs_inode: The eCryptfs inode
+ * @page_for_lower: The page containing the data to be written to the
+ * lower file
+ * @offset_in_page: The offset in the @page_for_lower from which to
+ * start writing the data
+ * @size: The amount of data from @page_for_lower to write to the
+ * lower file
+ *
+ * Determines the byte offset in the file for the given page and
+ * offset within the page, maps the page, and makes the call to write
+ * the contents of @page_for_lower to the lower inode.
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+int ecryptfs_write_lower_page_segment(struct inode *ecryptfs_inode,
+ struct page *page_for_lower,
+ size_t offset_in_page, size_t size)
+{
+ char *virt;
+ loff_t offset;
+ int rc;
+
+ offset = ((((loff_t)page_for_lower->index) << PAGE_SHIFT)
+ + offset_in_page);
+ virt = kmap(page_for_lower);
+ rc = ecryptfs_write_lower(ecryptfs_inode, virt, offset, size);
+ if (rc > 0)
+ rc = 0;
+ kunmap(page_for_lower);
+ return rc;
+}
+
+/**
+ * ecryptfs_write
+ * @ecryptfs_inode: The eCryptfs file into which to write
+ * @data: Virtual address where data to write is located
+ * @offset: Offset in the eCryptfs file at which to begin writing the
+ * data from @data
+ * @size: The number of bytes to write from @data
+ *
+ * Write an arbitrary amount of data to an arbitrary location in the
+ * eCryptfs inode page cache. This is done on a page-by-page, and then
+ * by an extent-by-extent, basis; individual extents are encrypted and
+ * written to the lower page cache (via VFS writes). This function
+ * takes care of all the address translation to locations in the lower
+ * filesystem; it also handles truncate events, writing out zeros
+ * where necessary.
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+int ecryptfs_write(struct inode *ecryptfs_inode, char *data, loff_t offset,
+ size_t size)
+{
+ struct page *ecryptfs_page;
+ struct ecryptfs_crypt_stat *crypt_stat;
+ char *ecryptfs_page_virt;
+ loff_t ecryptfs_file_size = i_size_read(ecryptfs_inode);
+ loff_t data_offset = 0;
+ loff_t pos;
+ int rc = 0;
+
+ crypt_stat = &ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat;
+ /*
+ * if we are writing beyond current size, then start pos
+ * at the current size - we'll fill in zeros from there.
+ */
+ if (offset > ecryptfs_file_size)
+ pos = ecryptfs_file_size;
+ else
+ pos = offset;
+ while (pos < (offset + size)) {
+ pgoff_t ecryptfs_page_idx = (pos >> PAGE_SHIFT);
+ size_t start_offset_in_page = (pos & ~PAGE_MASK);
+ size_t num_bytes = (PAGE_SIZE - start_offset_in_page);
+ loff_t total_remaining_bytes = ((offset + size) - pos);
+
+ if (fatal_signal_pending(current)) {
+ rc = -EINTR;
+ break;
+ }
+
+ if (num_bytes > total_remaining_bytes)
+ num_bytes = total_remaining_bytes;
+ if (pos < offset) {
+ /* remaining zeros to write, up to destination offset */
+ loff_t total_remaining_zeros = (offset - pos);
+
+ if (num_bytes > total_remaining_zeros)
+ num_bytes = total_remaining_zeros;
+ }
+ ecryptfs_page = ecryptfs_get_locked_page(ecryptfs_inode,
+ ecryptfs_page_idx);
+ if (IS_ERR(ecryptfs_page)) {
+ rc = PTR_ERR(ecryptfs_page);
+ printk(KERN_ERR "%s: Error getting page at "
+ "index [%ld] from eCryptfs inode "
+ "mapping; rc = [%d]\n", __func__,
+ ecryptfs_page_idx, rc);
+ goto out;
+ }
+ ecryptfs_page_virt = kmap_atomic(ecryptfs_page);
+
+ /*
+ * pos: where we're now writing, offset: where the request was
+ * If current pos is before request, we are filling zeros
+ * If we are at or beyond request, we are writing the *data*
+ * If we're in a fresh page beyond eof, zero it in either case
+ */
+ if (pos < offset || !start_offset_in_page) {
+ /* We are extending past the previous end of the file.
+ * Fill in zero values to the end of the page */
+ memset(((char *)ecryptfs_page_virt
+ + start_offset_in_page), 0,
+ PAGE_SIZE - start_offset_in_page);
+ }
+
+ /* pos >= offset, we are now writing the data request */
+ if (pos >= offset) {
+ memcpy(((char *)ecryptfs_page_virt
+ + start_offset_in_page),
+ (data + data_offset), num_bytes);
+ data_offset += num_bytes;
+ }
+ kunmap_atomic(ecryptfs_page_virt);
+ flush_dcache_page(ecryptfs_page);
+ SetPageUptodate(ecryptfs_page);
+ unlock_page(ecryptfs_page);
+ if (crypt_stat->flags & ECRYPTFS_ENCRYPTED)
+ rc = ecryptfs_encrypt_page(ecryptfs_page);
+ else
+ rc = ecryptfs_write_lower_page_segment(ecryptfs_inode,
+ ecryptfs_page,
+ start_offset_in_page,
+ data_offset);
+ put_page(ecryptfs_page);
+ if (rc) {
+ printk(KERN_ERR "%s: Error encrypting "
+ "page; rc = [%d]\n", __func__, rc);
+ goto out;
+ }
+ pos += num_bytes;
+ }
+ if (pos > ecryptfs_file_size) {
+ i_size_write(ecryptfs_inode, pos);
+ if (crypt_stat->flags & ECRYPTFS_ENCRYPTED) {
+ int rc2;
+
+ rc2 = ecryptfs_write_inode_size_to_metadata(
+ ecryptfs_inode);
+ if (rc2) {
+ printk(KERN_ERR "Problem with "
+ "ecryptfs_write_inode_size_to_metadata; "
+ "rc = [%d]\n", rc2);
+ if (!rc)
+ rc = rc2;
+ goto out;
+ }
+ }
+ }
+out:
+ return rc;
+}
+
+/**
+ * ecryptfs_read_lower
+ * @data: The read data is stored here by this function
+ * @offset: Byte offset in the lower file from which to read the data
+ * @size: Number of bytes to read from @offset of the lower file and
+ * store into @data
+ * @ecryptfs_inode: The eCryptfs inode
+ *
+ * Read @size bytes of data at byte offset @offset from the lower
+ * inode into memory location @data.
+ *
+ * Returns bytes read on success; 0 on EOF; less than zero on error
+ */
+int ecryptfs_read_lower(char *data, loff_t offset, size_t size,
+ struct inode *ecryptfs_inode)
+{
+ struct file *lower_file;
+ lower_file = ecryptfs_inode_to_private(ecryptfs_inode)->lower_file;
+ if (!lower_file)
+ return -EIO;
+ return kernel_read(lower_file, data, size, &offset);
+}
+
+/**
+ * ecryptfs_read_lower_page_segment
+ * @page_for_ecryptfs: The page into which data for eCryptfs will be
+ * written
+ * @offset_in_page: Offset in @page_for_ecryptfs from which to start
+ * writing
+ * @size: The number of bytes to write into @page_for_ecryptfs
+ * @ecryptfs_inode: The eCryptfs inode
+ *
+ * Determines the byte offset in the file for the given page and
+ * offset within the page, maps the page, and makes the call to read
+ * the contents of @page_for_ecryptfs from the lower inode.
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+int ecryptfs_read_lower_page_segment(struct page *page_for_ecryptfs,
+ pgoff_t page_index,
+ size_t offset_in_page, size_t size,
+ struct inode *ecryptfs_inode)
+{
+ char *virt;
+ loff_t offset;
+ int rc;
+
+ offset = ((((loff_t)page_index) << PAGE_SHIFT) + offset_in_page);
+ virt = kmap(page_for_ecryptfs);
+ rc = ecryptfs_read_lower(virt, offset, size, ecryptfs_inode);
+ if (rc > 0)
+ rc = 0;
+ kunmap(page_for_ecryptfs);
+ flush_dcache_page(page_for_ecryptfs);
+ return rc;
+}
diff --git a/fs/ecryptfs/super.c b/fs/ecryptfs/super.c
new file mode 100644
index 0000000..85411ce
--- /dev/null
+++ b/fs/ecryptfs/super.c
@@ -0,0 +1,193 @@
+/**
+ * eCryptfs: Linux filesystem encryption layer
+ *
+ * Copyright (C) 1997-2003 Erez Zadok
+ * Copyright (C) 2001-2003 Stony Brook University
+ * Copyright (C) 2004-2006 International Business Machines Corp.
+ * Author(s): Michael A. Halcrow <mahalcro@us.ibm.com>
+ * Michael C. Thompson <mcthomps@us.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ */
+
+#include <linux/fs.h>
+#include <linux/mount.h>
+#include <linux/key.h>
+#include <linux/slab.h>
+#include <linux/seq_file.h>
+#include <linux/file.h>
+#include <linux/statfs.h>
+#include <linux/magic.h>
+#include "ecryptfs_kernel.h"
+
+struct kmem_cache *ecryptfs_inode_info_cache;
+
+/**
+ * ecryptfs_alloc_inode - allocate an ecryptfs inode
+ * @sb: Pointer to the ecryptfs super block
+ *
+ * Called to bring an inode into existence.
+ *
+ * Only handle allocation, setting up structures should be done in
+ * ecryptfs_read_inode. This is because the kernel, between now and
+ * then, will 0 out the private data pointer.
+ *
+ * Returns a pointer to a newly allocated inode, NULL otherwise
+ */
+static struct inode *ecryptfs_alloc_inode(struct super_block *sb)
+{
+ struct ecryptfs_inode_info *inode_info;
+ struct inode *inode = NULL;
+
+ inode_info = kmem_cache_alloc(ecryptfs_inode_info_cache, GFP_KERNEL);
+ if (unlikely(!inode_info))
+ goto out;
+ if (ecryptfs_init_crypt_stat(&inode_info->crypt_stat)) {
+ kmem_cache_free(ecryptfs_inode_info_cache, inode_info);
+ goto out;
+ }
+ mutex_init(&inode_info->lower_file_mutex);
+ atomic_set(&inode_info->lower_file_count, 0);
+ inode_info->lower_file = NULL;
+ inode = &inode_info->vfs_inode;
+out:
+ return inode;
+}
+
+static void ecryptfs_i_callback(struct rcu_head *head)
+{
+ struct inode *inode = container_of(head, struct inode, i_rcu);
+ struct ecryptfs_inode_info *inode_info;
+ inode_info = ecryptfs_inode_to_private(inode);
+
+ kmem_cache_free(ecryptfs_inode_info_cache, inode_info);
+}
+
+/**
+ * ecryptfs_destroy_inode
+ * @inode: The ecryptfs inode
+ *
+ * This is used during the final destruction of the inode. All
+ * allocation of memory related to the inode, including allocated
+ * memory in the crypt_stat struct, will be released here.
+ * There should be no chance that this deallocation will be missed.
+ */
+static void ecryptfs_destroy_inode(struct inode *inode)
+{
+ struct ecryptfs_inode_info *inode_info;
+
+ inode_info = ecryptfs_inode_to_private(inode);
+ BUG_ON(inode_info->lower_file);
+ ecryptfs_destroy_crypt_stat(&inode_info->crypt_stat);
+ call_rcu(&inode->i_rcu, ecryptfs_i_callback);
+}
+
+/**
+ * ecryptfs_statfs
+ * @sb: The ecryptfs super block
+ * @buf: The struct kstatfs to fill in with stats
+ *
+ * Get the filesystem statistics. Currently, we let this pass right through
+ * to the lower filesystem and take no action ourselves.
+ */
+static int ecryptfs_statfs(struct dentry *dentry, struct kstatfs *buf)
+{
+ struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
+ int rc;
+
+ if (!lower_dentry->d_sb->s_op->statfs)
+ return -ENOSYS;
+
+ rc = lower_dentry->d_sb->s_op->statfs(lower_dentry, buf);
+ if (rc)
+ return rc;
+
+ buf->f_type = ECRYPTFS_SUPER_MAGIC;
+ rc = ecryptfs_set_f_namelen(&buf->f_namelen, buf->f_namelen,
+ &ecryptfs_superblock_to_private(dentry->d_sb)->mount_crypt_stat);
+
+ return rc;
+}
+
+/**
+ * ecryptfs_evict_inode
+ * @inode - The ecryptfs inode
+ *
+ * Called by iput() when the inode reference count reached zero
+ * and the inode is not hashed anywhere. Used to clear anything
+ * that needs to be, before the inode is completely destroyed and put
+ * on the inode free list. We use this to drop out reference to the
+ * lower inode.
+ */
+static void ecryptfs_evict_inode(struct inode *inode)
+{
+ truncate_inode_pages_final(&inode->i_data);
+ clear_inode(inode);
+ iput(ecryptfs_inode_to_lower(inode));
+}
+
+/**
+ * ecryptfs_show_options
+ *
+ * Prints the mount options for a given superblock.
+ * Returns zero; does not fail.
+ */
+static int ecryptfs_show_options(struct seq_file *m, struct dentry *root)
+{
+ struct super_block *sb = root->d_sb;
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat =
+ &ecryptfs_superblock_to_private(sb)->mount_crypt_stat;
+ struct ecryptfs_global_auth_tok *walker;
+
+ mutex_lock(&mount_crypt_stat->global_auth_tok_list_mutex);
+ list_for_each_entry(walker,
+ &mount_crypt_stat->global_auth_tok_list,
+ mount_crypt_stat_list) {
+ if (walker->flags & ECRYPTFS_AUTH_TOK_FNEK)
+ seq_printf(m, ",ecryptfs_fnek_sig=%s", walker->sig);
+ else
+ seq_printf(m, ",ecryptfs_sig=%s", walker->sig);
+ }
+ mutex_unlock(&mount_crypt_stat->global_auth_tok_list_mutex);
+
+ seq_printf(m, ",ecryptfs_cipher=%s",
+ mount_crypt_stat->global_default_cipher_name);
+
+ if (mount_crypt_stat->global_default_cipher_key_size)
+ seq_printf(m, ",ecryptfs_key_bytes=%zd",
+ mount_crypt_stat->global_default_cipher_key_size);
+ if (mount_crypt_stat->flags & ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED)
+ seq_printf(m, ",ecryptfs_passthrough");
+ if (mount_crypt_stat->flags & ECRYPTFS_XATTR_METADATA_ENABLED)
+ seq_printf(m, ",ecryptfs_xattr_metadata");
+ if (mount_crypt_stat->flags & ECRYPTFS_ENCRYPTED_VIEW_ENABLED)
+ seq_printf(m, ",ecryptfs_encrypted_view");
+ if (mount_crypt_stat->flags & ECRYPTFS_UNLINK_SIGS)
+ seq_printf(m, ",ecryptfs_unlink_sigs");
+ if (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_MOUNT_AUTH_TOK_ONLY)
+ seq_printf(m, ",ecryptfs_mount_auth_tok_only");
+
+ return 0;
+}
+
+const struct super_operations ecryptfs_sops = {
+ .alloc_inode = ecryptfs_alloc_inode,
+ .destroy_inode = ecryptfs_destroy_inode,
+ .statfs = ecryptfs_statfs,
+ .remount_fs = NULL,
+ .evict_inode = ecryptfs_evict_inode,
+ .show_options = ecryptfs_show_options
+};