2 * Copyright (C) 2015 Google, Inc.
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.
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.
15 #ifndef DM_ANDROID_VERITY_H
16 #define DM_ANDROID_VERITY_H
18 #include <crypto/sha.h>
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
30 #define FEC_MAGIC 0xFECFECFE
31 #define FEC_BLOCK_SIZE (4 * 1024)
34 #define FEC_ARG_LENGTH 300
36 #define VERITY_TABLE_OPT_RESTART "restart_on_corruption"
37 #define VERITY_TABLE_OPT_LOGGING "ignore_corruption"
38 #define VERITY_TABLE_OPT_IGNZERO "ignore_zero_blocks"
40 #define VERITY_TABLE_OPT_FEC_FORMAT \
41 "use_fec_from_device %s fec_start %llu fec_blocks %llu fec_roots %u ignore_zero_blocks"
42 #define VERITY_TABLE_OPT_FEC_ARGS 9
44 #define VERITY_DEBUG 0
46 #define DM_MSG_PREFIX "android-verity"
48 #define DM_LINEAR_ARGS 2
49 #define DM_LINEAR_TARGET_OFFSET "0"
52 * There can be two formats.
54 * <data_blocks> <verity_tree> <verity_metdata_32K><fec_data><fec_data_4K>
55 * if fec is not present
56 * <data_blocks> <verity_tree> <verity_metdata_32K>
58 /* TODO: rearrange structure to reduce memory holes
59 * depends on userspace change.
68 u8 hash[SHA256_DIGEST_SIZE];
71 struct android_metadata_header {
73 __le32 protocol_version;
74 char signature[RSANUMBYTES];
78 struct android_metadata {
79 struct android_metadata_header *header;
83 struct fec_ecc_metadata {
92 struct page **page_io;
96 extern struct target_type linear_target;
98 extern void dm_linear_dtr(struct dm_target *ti);
99 extern int dm_linear_map(struct dm_target *ti, struct bio *bio);
100 extern void dm_linear_status(struct dm_target *ti, status_type_t type,
101 unsigned status_flags, char *result, unsigned maxlen);
102 extern int dm_linear_ioctl(struct dm_target *ti, unsigned int cmd,
104 extern int dm_linear_merge(struct dm_target *ti, struct bvec_merge_data *bvm,
105 struct bio_vec *biovec, int max_size);
106 extern int dm_linear_iterate_devices(struct dm_target *ti,
107 iterate_devices_callout_fn fn, void *data);
108 extern int dm_linear_ctr(struct dm_target *ti, unsigned int argc, char **argv);
109 #endif /* DM_ANDROID_VERITY_H */