Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/drivers/nvdimm/security.c b/drivers/nvdimm/security.c
new file mode 100644
index 0000000..89b8597
--- /dev/null
+++ b/drivers/nvdimm/security.c
@@ -0,0 +1,553 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright(c) 2018 Intel Corporation. All rights reserved. */
+
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/ndctl.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/mm.h>
+#include <linux/cred.h>
+#include <linux/key.h>
+#include <linux/key-type.h>
+#include <keys/user-type.h>
+#include <keys/encrypted-type.h>
+#include "nd-core.h"
+#include "nd.h"
+
+#define NVDIMM_BASE_KEY 0
+#define NVDIMM_NEW_KEY 1
+
+static bool key_revalidate = true;
+module_param(key_revalidate, bool, 0444);
+MODULE_PARM_DESC(key_revalidate, "Require key validation at init.");
+
+static const char zero_key[NVDIMM_PASSPHRASE_LEN];
+
+static void *key_data(struct key *key)
+{
+ struct encrypted_key_payload *epayload = dereference_key_locked(key);
+
+ lockdep_assert_held_read(&key->sem);
+
+ return epayload->decrypted_data;
+}
+
+static void nvdimm_put_key(struct key *key)
+{
+ if (!key)
+ return;
+
+ up_read(&key->sem);
+ key_put(key);
+}
+
+/*
+ * Retrieve kernel key for DIMM and request from user space if
+ * necessary. Returns a key held for read and must be put by
+ * nvdimm_put_key() before the usage goes out of scope.
+ */
+static struct key *nvdimm_request_key(struct nvdimm *nvdimm)
+{
+ struct key *key = NULL;
+ static const char NVDIMM_PREFIX[] = "nvdimm:";
+ char desc[NVDIMM_KEY_DESC_LEN + sizeof(NVDIMM_PREFIX)];
+ struct device *dev = &nvdimm->dev;
+
+ sprintf(desc, "%s%s", NVDIMM_PREFIX, nvdimm->dimm_id);
+ key = request_key(&key_type_encrypted, desc, "");
+ if (IS_ERR(key)) {
+ if (PTR_ERR(key) == -ENOKEY)
+ dev_dbg(dev, "request_key() found no key\n");
+ else
+ dev_dbg(dev, "request_key() upcall failed\n");
+ key = NULL;
+ } else {
+ struct encrypted_key_payload *epayload;
+
+ down_read(&key->sem);
+ epayload = dereference_key_locked(key);
+ if (epayload->decrypted_datalen != NVDIMM_PASSPHRASE_LEN) {
+ up_read(&key->sem);
+ key_put(key);
+ key = NULL;
+ }
+ }
+
+ return key;
+}
+
+static const void *nvdimm_get_key_payload(struct nvdimm *nvdimm,
+ struct key **key)
+{
+ *key = nvdimm_request_key(nvdimm);
+ if (!*key)
+ return zero_key;
+
+ return key_data(*key);
+}
+
+static struct key *nvdimm_lookup_user_key(struct nvdimm *nvdimm,
+ key_serial_t id, int subclass)
+{
+ key_ref_t keyref;
+ struct key *key;
+ struct encrypted_key_payload *epayload;
+ struct device *dev = &nvdimm->dev;
+
+ keyref = lookup_user_key(id, 0, 0);
+ if (IS_ERR(keyref))
+ return NULL;
+
+ key = key_ref_to_ptr(keyref);
+ if (key->type != &key_type_encrypted) {
+ key_put(key);
+ return NULL;
+ }
+
+ dev_dbg(dev, "%s: key found: %#x\n", __func__, key_serial(key));
+
+ down_read_nested(&key->sem, subclass);
+ epayload = dereference_key_locked(key);
+ if (epayload->decrypted_datalen != NVDIMM_PASSPHRASE_LEN) {
+ up_read(&key->sem);
+ key_put(key);
+ key = NULL;
+ }
+ return key;
+}
+
+static const void *nvdimm_get_user_key_payload(struct nvdimm *nvdimm,
+ key_serial_t id, int subclass, struct key **key)
+{
+ *key = NULL;
+ if (id == 0) {
+ if (subclass == NVDIMM_BASE_KEY)
+ return zero_key;
+ else
+ return NULL;
+ }
+
+ *key = nvdimm_lookup_user_key(nvdimm, id, subclass);
+ if (!*key)
+ return NULL;
+
+ return key_data(*key);
+}
+
+
+static int nvdimm_key_revalidate(struct nvdimm *nvdimm)
+{
+ struct key *key;
+ int rc;
+ const void *data;
+
+ if (!nvdimm->sec.ops->change_key)
+ return -EOPNOTSUPP;
+
+ data = nvdimm_get_key_payload(nvdimm, &key);
+
+ /*
+ * Send the same key to the hardware as new and old key to
+ * verify that the key is good.
+ */
+ rc = nvdimm->sec.ops->change_key(nvdimm, data, data, NVDIMM_USER);
+ if (rc < 0) {
+ nvdimm_put_key(key);
+ return rc;
+ }
+
+ nvdimm_put_key(key);
+ nvdimm->sec.flags = nvdimm_security_flags(nvdimm, NVDIMM_USER);
+ return 0;
+}
+
+static int __nvdimm_security_unlock(struct nvdimm *nvdimm)
+{
+ struct device *dev = &nvdimm->dev;
+ struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
+ struct key *key;
+ const void *data;
+ int rc;
+
+ /* The bus lock should be held at the top level of the call stack */
+ lockdep_assert_held(&nvdimm_bus->reconfig_mutex);
+
+ if (!nvdimm->sec.ops || !nvdimm->sec.ops->unlock
+ || !nvdimm->sec.flags)
+ return -EIO;
+
+ /* No need to go further if security is disabled */
+ if (test_bit(NVDIMM_SECURITY_DISABLED, &nvdimm->sec.flags))
+ return 0;
+
+ if (test_bit(NDD_SECURITY_OVERWRITE, &nvdimm->flags)) {
+ dev_dbg(dev, "Security operation in progress.\n");
+ return -EBUSY;
+ }
+
+ /*
+ * If the pre-OS has unlocked the DIMM, attempt to send the key
+ * from request_key() to the hardware for verification. Failure
+ * to revalidate the key against the hardware results in a
+ * freeze of the security configuration. I.e. if the OS does not
+ * have the key, security is being managed pre-OS.
+ */
+ if (test_bit(NVDIMM_SECURITY_UNLOCKED, &nvdimm->sec.flags)) {
+ if (!key_revalidate)
+ return 0;
+
+ return nvdimm_key_revalidate(nvdimm);
+ } else
+ data = nvdimm_get_key_payload(nvdimm, &key);
+
+ rc = nvdimm->sec.ops->unlock(nvdimm, data);
+ dev_dbg(dev, "key: %d unlock: %s\n", key_serial(key),
+ rc == 0 ? "success" : "fail");
+
+ nvdimm_put_key(key);
+ nvdimm->sec.flags = nvdimm_security_flags(nvdimm, NVDIMM_USER);
+ return rc;
+}
+
+int nvdimm_security_unlock(struct device *dev)
+{
+ struct nvdimm *nvdimm = to_nvdimm(dev);
+ int rc;
+
+ nvdimm_bus_lock(dev);
+ rc = __nvdimm_security_unlock(nvdimm);
+ nvdimm_bus_unlock(dev);
+ return rc;
+}
+
+static int check_security_state(struct nvdimm *nvdimm)
+{
+ struct device *dev = &nvdimm->dev;
+
+ if (test_bit(NVDIMM_SECURITY_FROZEN, &nvdimm->sec.flags)) {
+ dev_dbg(dev, "Incorrect security state: %#lx\n",
+ nvdimm->sec.flags);
+ return -EIO;
+ }
+
+ if (test_bit(NDD_SECURITY_OVERWRITE, &nvdimm->flags)) {
+ dev_dbg(dev, "Security operation in progress.\n");
+ return -EBUSY;
+ }
+
+ return 0;
+}
+
+static int security_disable(struct nvdimm *nvdimm, unsigned int keyid)
+{
+ struct device *dev = &nvdimm->dev;
+ struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
+ struct key *key;
+ int rc;
+ const void *data;
+
+ /* The bus lock should be held at the top level of the call stack */
+ lockdep_assert_held(&nvdimm_bus->reconfig_mutex);
+
+ if (!nvdimm->sec.ops || !nvdimm->sec.ops->disable
+ || !nvdimm->sec.flags)
+ return -EOPNOTSUPP;
+
+ rc = check_security_state(nvdimm);
+ if (rc)
+ return rc;
+
+ data = nvdimm_get_user_key_payload(nvdimm, keyid,
+ NVDIMM_BASE_KEY, &key);
+ if (!data)
+ return -ENOKEY;
+
+ rc = nvdimm->sec.ops->disable(nvdimm, data);
+ dev_dbg(dev, "key: %d disable: %s\n", key_serial(key),
+ rc == 0 ? "success" : "fail");
+
+ nvdimm_put_key(key);
+ nvdimm->sec.flags = nvdimm_security_flags(nvdimm, NVDIMM_USER);
+ return rc;
+}
+
+static int security_update(struct nvdimm *nvdimm, unsigned int keyid,
+ unsigned int new_keyid,
+ enum nvdimm_passphrase_type pass_type)
+{
+ struct device *dev = &nvdimm->dev;
+ struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
+ struct key *key, *newkey;
+ int rc;
+ const void *data, *newdata;
+
+ /* The bus lock should be held at the top level of the call stack */
+ lockdep_assert_held(&nvdimm_bus->reconfig_mutex);
+
+ if (!nvdimm->sec.ops || !nvdimm->sec.ops->change_key
+ || !nvdimm->sec.flags)
+ return -EOPNOTSUPP;
+
+ rc = check_security_state(nvdimm);
+ if (rc)
+ return rc;
+
+ data = nvdimm_get_user_key_payload(nvdimm, keyid,
+ NVDIMM_BASE_KEY, &key);
+ if (!data)
+ return -ENOKEY;
+
+ newdata = nvdimm_get_user_key_payload(nvdimm, new_keyid,
+ NVDIMM_NEW_KEY, &newkey);
+ if (!newdata) {
+ nvdimm_put_key(key);
+ return -ENOKEY;
+ }
+
+ rc = nvdimm->sec.ops->change_key(nvdimm, data, newdata, pass_type);
+ dev_dbg(dev, "key: %d %d update%s: %s\n",
+ key_serial(key), key_serial(newkey),
+ pass_type == NVDIMM_MASTER ? "(master)" : "(user)",
+ rc == 0 ? "success" : "fail");
+
+ nvdimm_put_key(newkey);
+ nvdimm_put_key(key);
+ if (pass_type == NVDIMM_MASTER)
+ nvdimm->sec.ext_flags = nvdimm_security_flags(nvdimm,
+ NVDIMM_MASTER);
+ else
+ nvdimm->sec.flags = nvdimm_security_flags(nvdimm,
+ NVDIMM_USER);
+ return rc;
+}
+
+static int security_erase(struct nvdimm *nvdimm, unsigned int keyid,
+ enum nvdimm_passphrase_type pass_type)
+{
+ struct device *dev = &nvdimm->dev;
+ struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
+ struct key *key = NULL;
+ int rc;
+ const void *data;
+
+ /* The bus lock should be held at the top level of the call stack */
+ lockdep_assert_held(&nvdimm_bus->reconfig_mutex);
+
+ if (!nvdimm->sec.ops || !nvdimm->sec.ops->erase
+ || !nvdimm->sec.flags)
+ return -EOPNOTSUPP;
+
+ rc = check_security_state(nvdimm);
+ if (rc)
+ return rc;
+
+ if (!test_bit(NVDIMM_SECURITY_UNLOCKED, &nvdimm->sec.ext_flags)
+ && pass_type == NVDIMM_MASTER) {
+ dev_dbg(dev,
+ "Attempt to secure erase in wrong master state.\n");
+ return -EOPNOTSUPP;
+ }
+
+ data = nvdimm_get_user_key_payload(nvdimm, keyid,
+ NVDIMM_BASE_KEY, &key);
+ if (!data)
+ return -ENOKEY;
+
+ rc = nvdimm->sec.ops->erase(nvdimm, data, pass_type);
+ dev_dbg(dev, "key: %d erase%s: %s\n", key_serial(key),
+ pass_type == NVDIMM_MASTER ? "(master)" : "(user)",
+ rc == 0 ? "success" : "fail");
+
+ nvdimm_put_key(key);
+ nvdimm->sec.flags = nvdimm_security_flags(nvdimm, NVDIMM_USER);
+ return rc;
+}
+
+static int security_overwrite(struct nvdimm *nvdimm, unsigned int keyid)
+{
+ struct device *dev = &nvdimm->dev;
+ struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
+ struct key *key = NULL;
+ int rc;
+ const void *data;
+
+ /* The bus lock should be held at the top level of the call stack */
+ lockdep_assert_held(&nvdimm_bus->reconfig_mutex);
+
+ if (!nvdimm->sec.ops || !nvdimm->sec.ops->overwrite
+ || !nvdimm->sec.flags)
+ return -EOPNOTSUPP;
+
+ if (dev->driver == NULL) {
+ dev_dbg(dev, "Unable to overwrite while DIMM active.\n");
+ return -EINVAL;
+ }
+
+ rc = check_security_state(nvdimm);
+ if (rc)
+ return rc;
+
+ data = nvdimm_get_user_key_payload(nvdimm, keyid,
+ NVDIMM_BASE_KEY, &key);
+ if (!data)
+ return -ENOKEY;
+
+ rc = nvdimm->sec.ops->overwrite(nvdimm, data);
+ dev_dbg(dev, "key: %d overwrite submission: %s\n", key_serial(key),
+ rc == 0 ? "success" : "fail");
+
+ nvdimm_put_key(key);
+ if (rc == 0) {
+ set_bit(NDD_SECURITY_OVERWRITE, &nvdimm->flags);
+ set_bit(NDD_WORK_PENDING, &nvdimm->flags);
+ set_bit(NVDIMM_SECURITY_OVERWRITE, &nvdimm->sec.flags);
+ /*
+ * Make sure we don't lose device while doing overwrite
+ * query.
+ */
+ get_device(dev);
+ queue_delayed_work(system_wq, &nvdimm->dwork, 0);
+ }
+
+ return rc;
+}
+
+void __nvdimm_security_overwrite_query(struct nvdimm *nvdimm)
+{
+ struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(&nvdimm->dev);
+ int rc;
+ unsigned int tmo;
+
+ /* The bus lock should be held at the top level of the call stack */
+ lockdep_assert_held(&nvdimm_bus->reconfig_mutex);
+
+ /*
+ * Abort and release device if we no longer have the overwrite
+ * flag set. It means the work has been canceled.
+ */
+ if (!test_bit(NDD_WORK_PENDING, &nvdimm->flags))
+ return;
+
+ tmo = nvdimm->sec.overwrite_tmo;
+
+ if (!nvdimm->sec.ops || !nvdimm->sec.ops->query_overwrite
+ || !nvdimm->sec.flags)
+ return;
+
+ rc = nvdimm->sec.ops->query_overwrite(nvdimm);
+ if (rc == -EBUSY) {
+
+ /* setup delayed work again */
+ tmo += 10;
+ queue_delayed_work(system_wq, &nvdimm->dwork, tmo * HZ);
+ nvdimm->sec.overwrite_tmo = min(15U * 60U, tmo);
+ return;
+ }
+
+ if (rc < 0)
+ dev_dbg(&nvdimm->dev, "overwrite failed\n");
+ else
+ dev_dbg(&nvdimm->dev, "overwrite completed\n");
+
+ if (nvdimm->sec.overwrite_state)
+ sysfs_notify_dirent(nvdimm->sec.overwrite_state);
+ nvdimm->sec.overwrite_tmo = 0;
+ clear_bit(NDD_SECURITY_OVERWRITE, &nvdimm->flags);
+ clear_bit(NDD_WORK_PENDING, &nvdimm->flags);
+ put_device(&nvdimm->dev);
+ nvdimm->sec.flags = nvdimm_security_flags(nvdimm, NVDIMM_USER);
+ nvdimm->sec.flags = nvdimm_security_flags(nvdimm, NVDIMM_MASTER);
+}
+
+void nvdimm_security_overwrite_query(struct work_struct *work)
+{
+ struct nvdimm *nvdimm =
+ container_of(work, typeof(*nvdimm), dwork.work);
+
+ nvdimm_bus_lock(&nvdimm->dev);
+ __nvdimm_security_overwrite_query(nvdimm);
+ nvdimm_bus_unlock(&nvdimm->dev);
+}
+
+#define OPS \
+ C( OP_FREEZE, "freeze", 1), \
+ C( OP_DISABLE, "disable", 2), \
+ C( OP_UPDATE, "update", 3), \
+ C( OP_ERASE, "erase", 2), \
+ C( OP_OVERWRITE, "overwrite", 2), \
+ C( OP_MASTER_UPDATE, "master_update", 3), \
+ C( OP_MASTER_ERASE, "master_erase", 2)
+#undef C
+#define C(a, b, c) a
+enum nvdimmsec_op_ids { OPS };
+#undef C
+#define C(a, b, c) { b, c }
+static struct {
+ const char *name;
+ int args;
+} ops[] = { OPS };
+#undef C
+
+#define SEC_CMD_SIZE 32
+#define KEY_ID_SIZE 10
+
+ssize_t nvdimm_security_store(struct device *dev, const char *buf, size_t len)
+{
+ struct nvdimm *nvdimm = to_nvdimm(dev);
+ ssize_t rc;
+ char cmd[SEC_CMD_SIZE+1], keystr[KEY_ID_SIZE+1],
+ nkeystr[KEY_ID_SIZE+1];
+ unsigned int key, newkey;
+ int i;
+
+ rc = sscanf(buf, "%"__stringify(SEC_CMD_SIZE)"s"
+ " %"__stringify(KEY_ID_SIZE)"s"
+ " %"__stringify(KEY_ID_SIZE)"s",
+ cmd, keystr, nkeystr);
+ if (rc < 1)
+ return -EINVAL;
+ for (i = 0; i < ARRAY_SIZE(ops); i++)
+ if (sysfs_streq(cmd, ops[i].name))
+ break;
+ if (i >= ARRAY_SIZE(ops))
+ return -EINVAL;
+ if (ops[i].args > 1)
+ rc = kstrtouint(keystr, 0, &key);
+ if (rc >= 0 && ops[i].args > 2)
+ rc = kstrtouint(nkeystr, 0, &newkey);
+ if (rc < 0)
+ return rc;
+
+ if (i == OP_FREEZE) {
+ dev_dbg(dev, "freeze\n");
+ rc = nvdimm_security_freeze(nvdimm);
+ } else if (i == OP_DISABLE) {
+ dev_dbg(dev, "disable %u\n", key);
+ rc = security_disable(nvdimm, key);
+ } else if (i == OP_UPDATE || i == OP_MASTER_UPDATE) {
+ dev_dbg(dev, "%s %u %u\n", ops[i].name, key, newkey);
+ rc = security_update(nvdimm, key, newkey, i == OP_UPDATE
+ ? NVDIMM_USER : NVDIMM_MASTER);
+ } else if (i == OP_ERASE || i == OP_MASTER_ERASE) {
+ dev_dbg(dev, "%s %u\n", ops[i].name, key);
+ if (atomic_read(&nvdimm->busy)) {
+ dev_dbg(dev, "Unable to secure erase while DIMM active.\n");
+ return -EBUSY;
+ }
+ rc = security_erase(nvdimm, key, i == OP_ERASE
+ ? NVDIMM_USER : NVDIMM_MASTER);
+ } else if (i == OP_OVERWRITE) {
+ dev_dbg(dev, "overwrite %u\n", key);
+ if (atomic_read(&nvdimm->busy)) {
+ dev_dbg(dev, "Unable to overwrite while DIMM active.\n");
+ return -EBUSY;
+ }
+ rc = security_overwrite(nvdimm, key);
+ } else
+ return -EINVAL;
+
+ if (rc == 0)
+ rc = len;
+ return rc;
+}