Boot: add original files from MCUBoot and Zephyr project
Aligned with MCUBoot version 1.0.0
MCUBoot files:
-- bl2/ext/mcuboot
Aligned with Zephyr version 1.10.0
Zephyr files:
-- bl2/ext/mcuboot/include/util.h
-- platform/ext/target/common/flash.h
Change-Id: I314c3efa2bd2c13a4a2eaefeb5da43e53e988638
Signed-off-by: Tamas Ban <tamas.ban@arm.com>
diff --git a/bl2/ext/mcuboot/bootutil/src/image_validate.c b/bl2/ext/mcuboot/bootutil/src/image_validate.c
new file mode 100644
index 0000000..5b2b9a0
--- /dev/null
+++ b/bl2/ext/mcuboot/bootutil/src/image_validate.c
@@ -0,0 +1,260 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+#include <assert.h>
+#include <stddef.h>
+#include <inttypes.h>
+#include <string.h>
+
+#include "hal/hal_flash.h"
+#include "flash_map/flash_map.h"
+#include "bootutil/image.h"
+#include "bootutil/sha256.h"
+#include "bootutil/sign_key.h"
+
+#ifdef MCUBOOT_MYNEWT
+#include "mcuboot_config/mcuboot_config.h"
+#endif
+
+#ifdef MCUBOOT_SIGN_RSA
+#include "mbedtls/rsa.h"
+#endif
+#if defined(MCUBOOT_SIGN_EC) || defined(MCUBOOT_SIGN_EC256)
+#include "mbedtls/ecdsa.h"
+#endif
+#include "mbedtls/asn1.h"
+
+#include "bootutil_priv.h"
+
+/*
+ * Compute SHA256 over the image.
+ */
+static int
+bootutil_img_hash(struct image_header *hdr, const struct flash_area *fap,
+ uint8_t *tmp_buf, uint32_t tmp_buf_sz,
+ uint8_t *hash_result, uint8_t *seed, int seed_len)
+{
+ bootutil_sha256_context sha256_ctx;
+ uint32_t blk_sz;
+ uint32_t size;
+ uint32_t off;
+ int rc;
+
+ bootutil_sha256_init(&sha256_ctx);
+
+ /* in some cases (split image) the hash is seeded with data from
+ * the loader image */
+ if(seed && (seed_len > 0)) {
+ bootutil_sha256_update(&sha256_ctx, seed, seed_len);
+ }
+
+ size = hdr->ih_img_size + hdr->ih_hdr_size;
+
+ /*
+ * Hash is computed over image header and image itself. No TLV is
+ * included ATM.
+ */
+ size = hdr->ih_img_size + hdr->ih_hdr_size;
+ for (off = 0; off < size; off += blk_sz) {
+ blk_sz = size - off;
+ if (blk_sz > tmp_buf_sz) {
+ blk_sz = tmp_buf_sz;
+ }
+ rc = flash_area_read(fap, off, tmp_buf, blk_sz);
+ if (rc) {
+ return rc;
+ }
+ bootutil_sha256_update(&sha256_ctx, tmp_buf, blk_sz);
+ }
+ bootutil_sha256_finish(&sha256_ctx, hash_result);
+
+ return 0;
+}
+
+/*
+ * Currently, we only support being able to verify one type of
+ * signature, because there is a single verification function that we
+ * call. List the type of TLV we are expecting. If we aren't
+ * configured for any signature, don't define this macro.
+ */
+#if defined(MCUBOOT_SIGN_RSA)
+# define EXPECTED_SIG_TLV IMAGE_TLV_RSA2048_PSS
+# define EXPECTED_SIG_LEN(x) ((x) == 256) /* 2048 bits */
+# if defined(MCUBOOT_SIGN_EC) || defined(MCUBOOT_SIGN_EC256)
+# error "Multiple signature types not yet supported"
+# endif
+#elif defined(MCUBOOT_SIGN_EC)
+# define EXPECTED_SIG_TLV IMAGE_TLV_ECDSA224
+# define EXPECTED_SIG_LEN(x) ((x) >= 64) /* oids + 2 * 28 bytes */
+# if defined(MCUBOOT_SIGN_EC256)
+# error "Multiple signature types not yet supported"
+# endif
+#elif defined(MCUBOOT_SIGN_EC256)
+# define EXPECTED_SIG_TLV IMAGE_TLV_ECDSA256
+# define EXPECTED_SIG_LEN(x) ((x) >= 72) /* oids + 2 * 32 bytes */
+#endif
+
+#ifdef EXPECTED_SIG_TLV
+static int
+bootutil_find_key(uint8_t *keyhash, uint8_t keyhash_len)
+{
+ bootutil_sha256_context sha256_ctx;
+ int i;
+ const struct bootutil_key *key;
+ uint8_t hash[32];
+
+ assert(keyhash_len <= 32);
+
+ for (i = 0; i < bootutil_key_cnt; i++) {
+ key = &bootutil_keys[i];
+ bootutil_sha256_init(&sha256_ctx);
+ bootutil_sha256_update(&sha256_ctx, key->key, *key->len);
+ bootutil_sha256_finish(&sha256_ctx, hash);
+ if (!memcmp(hash, keyhash, keyhash_len)) {
+ return i;
+ }
+ }
+ return -1;
+}
+#endif
+
+/*
+ * Verify the integrity of the image.
+ * Return non-zero if image could not be validated/does not validate.
+ */
+int
+bootutil_img_validate(struct image_header *hdr, const struct flash_area *fap,
+ uint8_t *tmp_buf, uint32_t tmp_buf_sz,
+ uint8_t *seed, int seed_len, uint8_t *out_hash)
+{
+ uint32_t off;
+ uint32_t end;
+ int sha256_valid = 0;
+ struct image_tlv_info info;
+#ifdef EXPECTED_SIG_TLV
+ int valid_signature = 0;
+ int key_id = -1;
+#endif
+ struct image_tlv tlv;
+ uint8_t buf[256];
+ uint8_t hash[32];
+ int rc;
+
+ rc = bootutil_img_hash(hdr, fap, tmp_buf, tmp_buf_sz, hash,
+ seed, seed_len);
+ if (rc) {
+ return rc;
+ }
+
+ if (out_hash) {
+ memcpy(out_hash, hash, 32);
+ }
+
+ /* The TLVs come after the image. */
+ /* After image there are TLVs. */
+ off = hdr->ih_img_size + hdr->ih_hdr_size;
+
+ rc = flash_area_read(fap, off, &info, sizeof(info));
+ if (rc) {
+ return rc;
+ }
+ if (info.it_magic != IMAGE_TLV_INFO_MAGIC) {
+ return -1;
+ }
+ end = off + info.it_tlv_tot;
+ off += sizeof(info);
+
+ /*
+ * Traverse through all of the TLVs, performing any checks we know
+ * and are able to do.
+ */
+ for (; off < end; off += sizeof(tlv) + tlv.it_len) {
+ rc = flash_area_read(fap, off, &tlv, sizeof tlv);
+ if (rc) {
+ return rc;
+ }
+
+ if (tlv.it_type == IMAGE_TLV_SHA256) {
+ /*
+ * Verify the SHA256 image hash. This must always be
+ * present.
+ */
+ if (tlv.it_len != sizeof(hash)) {
+ return -1;
+ }
+ rc = flash_area_read(fap, off + sizeof(tlv), buf, sizeof hash);
+ if (rc) {
+ return rc;
+ }
+ if (memcmp(hash, buf, sizeof(hash))) {
+ return -1;
+ }
+
+ sha256_valid = 1;
+#ifdef EXPECTED_SIG_TLV
+ } else if (tlv.it_type == IMAGE_TLV_KEYHASH) {
+ /*
+ * Determine which key we should be checking.
+ */
+ if (tlv.it_len > 32) {
+ return -1;
+ }
+ rc = flash_area_read(fap, off + sizeof tlv, buf, tlv.it_len);
+ if (rc) {
+ return rc;
+ }
+ key_id = bootutil_find_key(buf, tlv.it_len);
+ /*
+ * The key may not be found, which is acceptable. There
+ * can be multiple signatures, each preceded by a key.
+ */
+ } else if (tlv.it_type == EXPECTED_SIG_TLV) {
+ /* Ignore this signature if it is out of bounds. */
+ if (key_id < 0 || key_id >= bootutil_key_cnt) {
+ key_id = -1;
+ continue;
+ }
+ if (!EXPECTED_SIG_LEN(tlv.it_len) || tlv.it_len > sizeof(buf)) {
+ return -1;
+ }
+ rc = flash_area_read(fap, off + sizeof(tlv), buf, tlv.it_len);
+ if (rc) {
+ return -1;
+ }
+ rc = bootutil_verify_sig(hash, sizeof(hash), buf, tlv.it_len, key_id);
+ if (rc == 0) {
+ valid_signature = 1;
+ }
+ key_id = -1;
+#endif
+ }
+ }
+
+ if (!sha256_valid) {
+ return -1;
+ }
+
+#ifdef EXPECTED_SIG_TLV
+ if (!valid_signature) {
+ return -1;
+ }
+#endif
+
+ return 0;
+}