dm-verity can use separate device for hash verification, in this case there is a superblock in the first sector. See http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=blob;f=Documentation/device-mapper/verity.txt for more info. Signed-off-by: Milan Broz <mbroz@xxxxxxxxxx> --- libblkid/src/superblocks/lvm.c | 41 ++++++++++++++++++++++++++++++++ libblkid/src/superblocks/superblocks.c | 1 + libblkid/src/superblocks/superblocks.h | 1 + 3 files changed, 43 insertions(+) diff --git a/libblkid/src/superblocks/lvm.c b/libblkid/src/superblocks/lvm.c index 3a9807c..57d2b6e 100644 --- a/libblkid/src/superblocks/lvm.c +++ b/libblkid/src/superblocks/lvm.c @@ -4,6 +4,7 @@ * Copyright (C) 2001 by Andreas Dilger * Copyright (C) 2004 Kay Sievers <kay.sievers@xxxxxxxx> * Copyright (C) 2008 Karel Zak <kzak@xxxxxxxxxx> + * Copyright (C) 2012 Milan Broz <mbroz@xxxxxxxxxx> * * This file may be redistributed under the terms of the * GNU Lesser General Public License. @@ -142,6 +143,34 @@ static int probe_lvm1(blkid_probe pr, const struct blkid_idmag *mag) return 0; } +#define MAX_SALT_SIZE 384 +struct verity_sb { + uint8_t signature[8]; + uint8_t version; + uint8_t data_block_bits; + uint8_t hash_block_bits; + uint8_t pad1[1]; + uint16_t salt_size; + uint8_t pad2[2]; + uint32_t data_blocks_hi; + uint32_t data_blocks_lo; + uint8_t algorithm[16]; + uint8_t salt[MAX_SALT_SIZE]; + uint8_t pad3[88]; +} __attribute__((packed)); + +static int probe_verity(blkid_probe pr, const struct blkid_idmag *mag) +{ + struct verity_sb *sb; + + sb = blkid_probe_get_sb(pr, mag, struct verity_sb); + if (sb == NULL) + return -1; + + blkid_probe_sprintf_version(pr, "%u", sb->version); + return 0; +} + /* NOTE: the original libblkid uses "lvm2pv" as a name */ const struct blkid_idinfo lvm2_idinfo = { @@ -180,3 +209,15 @@ const struct blkid_idinfo snapcow_idinfo = { NULL } } }; + +const struct blkid_idinfo verity_hash_idinfo = +{ + .name = "DM_verity_hash", + .usage = BLKID_USAGE_CRYPTO, + .probefunc = probe_verity, + .magics = + { + { .magic = "verity\0\0", .len = 8 }, + { NULL } + } +}; diff --git a/libblkid/src/superblocks/superblocks.c b/libblkid/src/superblocks/superblocks.c index 91f4f88..879a40f 100644 --- a/libblkid/src/superblocks/superblocks.c +++ b/libblkid/src/superblocks/superblocks.c @@ -96,6 +96,7 @@ static const struct blkid_idinfo *idinfos[] = &lvm2_idinfo, &lvm1_idinfo, &snapcow_idinfo, + &verity_hash_idinfo, &luks_idinfo, &vmfs_volume_idinfo, diff --git a/libblkid/src/superblocks/superblocks.h b/libblkid/src/superblocks/superblocks.h index c97e447..086a568 100644 --- a/libblkid/src/superblocks/superblocks.h +++ b/libblkid/src/superblocks/superblocks.h @@ -50,6 +50,7 @@ extern const struct blkid_idinfo hpfs_idinfo; extern const struct blkid_idinfo lvm2_idinfo; extern const struct blkid_idinfo lvm1_idinfo; extern const struct blkid_idinfo snapcow_idinfo; +extern const struct blkid_idinfo verity_hash_idinfo; extern const struct blkid_idinfo luks_idinfo; extern const struct blkid_idinfo highpoint37x_idinfo; extern const struct blkid_idinfo highpoint45x_idinfo; -- 1.7.10 -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
