1*4882a593Smuzhiyun /*
2*4882a593Smuzhiyun * Copyright (C) 2016 The Android Open Source Project
3*4882a593Smuzhiyun *
4*4882a593Smuzhiyun * Permission is hereby granted, free of charge, to any person
5*4882a593Smuzhiyun * obtaining a copy of this software and associated documentation
6*4882a593Smuzhiyun * files (the "Software"), to deal in the Software without
7*4882a593Smuzhiyun * restriction, including without limitation the rights to use, copy,
8*4882a593Smuzhiyun * modify, merge, publish, distribute, sublicense, and/or sell copies
9*4882a593Smuzhiyun * of the Software, and to permit persons to whom the Software is
10*4882a593Smuzhiyun * furnished to do so, subject to the following conditions:
11*4882a593Smuzhiyun *
12*4882a593Smuzhiyun * The above copyright notice and this permission notice shall be
13*4882a593Smuzhiyun * included in all copies or substantial portions of the Software.
14*4882a593Smuzhiyun *
15*4882a593Smuzhiyun * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
16*4882a593Smuzhiyun * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
17*4882a593Smuzhiyun * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
18*4882a593Smuzhiyun * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
19*4882a593Smuzhiyun * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
20*4882a593Smuzhiyun * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
21*4882a593Smuzhiyun * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
22*4882a593Smuzhiyun * SOFTWARE.
23*4882a593Smuzhiyun */
24*4882a593Smuzhiyun
25*4882a593Smuzhiyun #include <android_avb/avb_hashtree_descriptor.h>
26*4882a593Smuzhiyun #include <android_avb/avb_util.h>
27*4882a593Smuzhiyun
avb_hashtree_descriptor_validate_and_byteswap(const AvbHashtreeDescriptor * src,AvbHashtreeDescriptor * dest)28*4882a593Smuzhiyun bool avb_hashtree_descriptor_validate_and_byteswap(
29*4882a593Smuzhiyun const AvbHashtreeDescriptor* src, AvbHashtreeDescriptor* dest) {
30*4882a593Smuzhiyun uint64_t expected_size;
31*4882a593Smuzhiyun
32*4882a593Smuzhiyun avb_memcpy(dest, src, sizeof(AvbHashtreeDescriptor));
33*4882a593Smuzhiyun
34*4882a593Smuzhiyun if (!avb_descriptor_validate_and_byteswap((const AvbDescriptor*)src,
35*4882a593Smuzhiyun (AvbDescriptor*)dest))
36*4882a593Smuzhiyun return false;
37*4882a593Smuzhiyun
38*4882a593Smuzhiyun if (dest->parent_descriptor.tag != AVB_DESCRIPTOR_TAG_HASHTREE) {
39*4882a593Smuzhiyun avb_error("Invalid tag for hashtree descriptor.\n");
40*4882a593Smuzhiyun return false;
41*4882a593Smuzhiyun }
42*4882a593Smuzhiyun
43*4882a593Smuzhiyun dest->dm_verity_version = avb_be32toh(dest->dm_verity_version);
44*4882a593Smuzhiyun dest->image_size = avb_be64toh(dest->image_size);
45*4882a593Smuzhiyun dest->tree_offset = avb_be64toh(dest->tree_offset);
46*4882a593Smuzhiyun dest->tree_size = avb_be64toh(dest->tree_size);
47*4882a593Smuzhiyun dest->data_block_size = avb_be32toh(dest->data_block_size);
48*4882a593Smuzhiyun dest->hash_block_size = avb_be32toh(dest->hash_block_size);
49*4882a593Smuzhiyun dest->fec_num_roots = avb_be32toh(dest->fec_num_roots);
50*4882a593Smuzhiyun dest->fec_offset = avb_be64toh(dest->fec_offset);
51*4882a593Smuzhiyun dest->fec_size = avb_be64toh(dest->fec_size);
52*4882a593Smuzhiyun dest->partition_name_len = avb_be32toh(dest->partition_name_len);
53*4882a593Smuzhiyun dest->salt_len = avb_be32toh(dest->salt_len);
54*4882a593Smuzhiyun dest->root_digest_len = avb_be32toh(dest->root_digest_len);
55*4882a593Smuzhiyun dest->flags = avb_be32toh(dest->flags);
56*4882a593Smuzhiyun
57*4882a593Smuzhiyun /* Check that partition_name, salt, and root_digest are fully contained. */
58*4882a593Smuzhiyun expected_size = sizeof(AvbHashtreeDescriptor) - sizeof(AvbDescriptor);
59*4882a593Smuzhiyun if (!avb_safe_add_to(&expected_size, dest->partition_name_len) ||
60*4882a593Smuzhiyun !avb_safe_add_to(&expected_size, dest->salt_len) ||
61*4882a593Smuzhiyun !avb_safe_add_to(&expected_size, dest->root_digest_len)) {
62*4882a593Smuzhiyun avb_error("Overflow while adding up sizes.\n");
63*4882a593Smuzhiyun return false;
64*4882a593Smuzhiyun }
65*4882a593Smuzhiyun if (expected_size > dest->parent_descriptor.num_bytes_following) {
66*4882a593Smuzhiyun avb_error("Descriptor payload size overflow.\n");
67*4882a593Smuzhiyun return false;
68*4882a593Smuzhiyun }
69*4882a593Smuzhiyun return true;
70*4882a593Smuzhiyun }
71