| rjw | 1f88458 | 2022-01-06 17:20:42 +0800 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright (C) 2015 Google, Inc. |
| 3 | * |
| 4 | * This software is licensed under the terms of the GNU General Public |
| 5 | * License version 2, as published by the Free Software Foundation, and |
| 6 | * may be copied, distributed, and modified under those terms. |
| 7 | * |
| 8 | * This program is distributed in the hope that it will be useful, |
| 9 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 10 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 11 | * GNU General Public License for more details. |
| 12 | * |
| 13 | */ |
| 14 | |
| 15 | #ifndef DM_ANDROID_VERITY_H |
| 16 | #define DM_ANDROID_VERITY_H |
| 17 | |
| 18 | #include <crypto/sha.h> |
| 19 | |
| 20 | #define RSANUMBYTES 256 |
| 21 | #define VERITY_METADATA_MAGIC_NUMBER 0xb001b001 |
| 22 | #define VERITY_METADATA_MAGIC_DISABLE 0x46464f56 |
| 23 | #define VERITY_METADATA_VERSION 0 |
| 24 | #define VERITY_STATE_DISABLE 1 |
| 25 | #define DATA_BLOCK_SIZE (4 * 1024) |
| 26 | #define VERITY_METADATA_SIZE (8 * DATA_BLOCK_SIZE) |
| 27 | #define VERITY_TABLE_ARGS 10 |
| 28 | #define VERITY_COMMANDLINE_PARAM_LENGTH 20 |
| 29 | #define BUILD_VARIANT 20 |
| 30 | |
| 31 | /* |
| 32 | * <subject>:<sha1-id> is the format for the identifier. |
| 33 | * subject can either be the Common Name(CN) + Organization Name(O) or |
| 34 | * just the CN if the it is prefixed with O |
| 35 | * From https://tools.ietf.org/html/rfc5280#appendix-A |
| 36 | * ub-organization-name-length INTEGER ::= 64 |
| 37 | * ub-common-name-length INTEGER ::= 64 |
| 38 | * |
| 39 | * http://lxr.free-electrons.com/source/crypto/asymmetric_keys/x509_cert_parser.c?v=3.9#L278 |
| 40 | * ctx->o_size + 2 + ctx->cn_size + 1 |
| 41 | * + 41 characters for ":" and sha1 id |
| 42 | * 64 + 2 + 64 + 1 + 1 + 40 (172) |
| 43 | * setting VERITY_DEFAULT_KEY_ID_LENGTH to 200 characters. |
| 44 | */ |
| 45 | #define VERITY_DEFAULT_KEY_ID_LENGTH 200 |
| 46 | |
| 47 | #define FEC_MAGIC 0xFECFECFE |
| 48 | #define FEC_BLOCK_SIZE (4 * 1024) |
| 49 | #define FEC_VERSION 0 |
| 50 | #define FEC_RSM 255 |
| 51 | #define FEC_ARG_LENGTH 300 |
| 52 | |
| 53 | #define VERITY_TABLE_OPT_RESTART "restart_on_corruption" |
| 54 | #define VERITY_TABLE_OPT_LOGGING "ignore_corruption" |
| 55 | #define VERITY_TABLE_OPT_IGNZERO "ignore_zero_blocks" |
| 56 | |
| 57 | #define VERITY_TABLE_OPT_FEC_FORMAT \ |
| 58 | "use_fec_from_device %s fec_start %llu fec_blocks %llu fec_roots %u ignore_zero_blocks" |
| 59 | #define VERITY_TABLE_OPT_FEC_ARGS 9 |
| 60 | |
| 61 | #define VERITY_DEBUG 0 |
| 62 | |
| 63 | #define DM_MSG_PREFIX "android-verity" |
| 64 | |
| 65 | #define DM_LINEAR_ARGS 2 |
| 66 | #define DM_LINEAR_TARGET_OFFSET "0" |
| 67 | |
| 68 | /* |
| 69 | * There can be two formats. |
| 70 | * if fec is present |
| 71 | * <data_blocks> <verity_tree> <verity_metdata_32K><fec_data><fec_data_4K> |
| 72 | * if fec is not present |
| 73 | * <data_blocks> <verity_tree> <verity_metdata_32K> |
| 74 | */ |
| 75 | struct fec_header { |
| 76 | __le32 magic; |
| 77 | __le32 version; |
| 78 | __le32 size; |
| 79 | __le32 roots; |
| 80 | __le32 fec_size; |
| 81 | __le64 inp_size; |
| 82 | u8 hash[SHA256_DIGEST_SIZE]; |
| 83 | } __attribute__((packed)); |
| 84 | |
| 85 | struct android_metadata_header { |
| 86 | __le32 magic_number; |
| 87 | __le32 protocol_version; |
| 88 | char signature[RSANUMBYTES]; |
| 89 | __le32 table_length; |
| 90 | }; |
| 91 | |
| 92 | struct android_metadata { |
| 93 | struct android_metadata_header *header; |
| 94 | char *verity_table; |
| 95 | }; |
| 96 | |
| 97 | struct fec_ecc_metadata { |
| 98 | bool valid; |
| 99 | u32 roots; |
| 100 | u64 blocks; |
| 101 | u64 rounds; |
| 102 | u64 start; |
| 103 | }; |
| 104 | |
| 105 | struct bio_read { |
| 106 | struct page **page_io; |
| 107 | int number_of_pages; |
| 108 | }; |
| 109 | |
| 110 | extern struct target_type linear_target; |
| 111 | |
| 112 | extern void dm_linear_dtr(struct dm_target *ti); |
| 113 | extern int dm_linear_map(struct dm_target *ti, struct bio *bio); |
| 114 | extern int dm_linear_end_io(struct dm_target *ti, struct bio *bio, |
| 115 | blk_status_t *error); |
| 116 | extern void dm_linear_status(struct dm_target *ti, status_type_t type, |
| 117 | unsigned status_flags, char *result, unsigned maxlen); |
| 118 | extern int dm_linear_prepare_ioctl(struct dm_target *ti, |
| 119 | struct block_device **bdev, fmode_t *mode); |
| 120 | extern int dm_linear_iterate_devices(struct dm_target *ti, |
| 121 | iterate_devices_callout_fn fn, void *data); |
| 122 | extern int dm_linear_ctr(struct dm_target *ti, unsigned int argc, char **argv); |
| 123 | extern long dm_linear_dax_direct_access(struct dm_target *ti, pgoff_t pgoff, |
| 124 | long nr_pages, void **kaddr, |
| 125 | pfn_t *pfn); |
| 126 | extern size_t dm_linear_dax_copy_from_iter(struct dm_target *ti, pgoff_t pgoff, |
| 127 | void *addr, size_t bytes, struct iov_iter *i); |
| 128 | #endif /* DM_ANDROID_VERITY_H */ |