1 /*
2 * Copyright (C) 2016 The Android Open Source Project
3 *
4 * Permission is hereby granted, free of charge, to any person
5 * obtaining a copy of this software and associated documentation
6 * files (the "Software"), to deal in the Software without
7 * restriction, including without limitation the rights to use, copy,
8 * modify, merge, publish, distribute, sublicense, and/or sell copies
9 * of the Software, and to permit persons to whom the Software is
10 * furnished to do so, subject to the following conditions:
11 *
12 * The above copyright notice and this permission notice shall be
13 * included in all copies or substantial portions of the Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
16 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
17 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
18 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
19 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
20 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
21 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
22 * SOFTWARE.
23 */
24
25 #include "avb_hash_descriptor.h"
26 #include "avb_util.h"
27
avb_hash_descriptor_validate_and_byteswap(const AvbHashDescriptor * src,AvbHashDescriptor * dest)28 bool avb_hash_descriptor_validate_and_byteswap(const AvbHashDescriptor* src,
29 AvbHashDescriptor* dest) {
30 uint64_t expected_size;
31
32 avb_memcpy(dest, src, sizeof(AvbHashDescriptor));
33
34 if (!avb_descriptor_validate_and_byteswap((const AvbDescriptor*)src,
35 (AvbDescriptor*)dest))
36 return false;
37
38 if (dest->parent_descriptor.tag != AVB_DESCRIPTOR_TAG_HASH) {
39 avb_error("Invalid tag for hash descriptor.\n");
40 return false;
41 }
42
43 dest->image_size = avb_be64toh(dest->image_size);
44 dest->partition_name_len = avb_be32toh(dest->partition_name_len);
45 dest->salt_len = avb_be32toh(dest->salt_len);
46 dest->digest_len = avb_be32toh(dest->digest_len);
47 dest->flags = avb_be32toh(dest->flags);
48
49 /* Check that partition_name, salt, and digest are fully contained. */
50 expected_size = sizeof(AvbHashDescriptor) - sizeof(AvbDescriptor);
51 if (!avb_safe_add_to(&expected_size, dest->partition_name_len) ||
52 !avb_safe_add_to(&expected_size, dest->salt_len) ||
53 !avb_safe_add_to(&expected_size, dest->digest_len)) {
54 avb_error("Overflow while adding up sizes.\n");
55 return false;
56 }
57 if (expected_size > dest->parent_descriptor.num_bytes_following) {
58 avb_error("Descriptor payload size overflow.\n");
59 return false;
60 }
61 return true;
62 }
63