blob: 2e427de9397e10c03e628d58cdb1b5389f5b915a
| 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 | |
| 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 | |
| 48 | /* Check that partition_name, salt, and digest are fully contained. */ |
| 49 | expected_size = sizeof(AvbHashDescriptor) - sizeof(AvbDescriptor); |
| 50 | if (!avb_safe_add_to(&expected_size, dest->partition_name_len) || |
| 51 | !avb_safe_add_to(&expected_size, dest->salt_len) || |
| 52 | !avb_safe_add_to(&expected_size, dest->digest_len)) { |
| 53 | avb_error("Overflow while adding up sizes.\n"); |
| 54 | return false; |
| 55 | } |
| 56 | if (expected_size > dest->parent_descriptor.num_bytes_following) { |
| 57 | avb_error("Descriptor payload size overflow.\n"); |
| 58 | return false; |
| 59 | } |
| 60 | return true; |
| 61 | } |
| 62 |