diff options
Diffstat (limited to 'drivers/md/dm-integrity.c')
-rw-r--r-- | drivers/md/dm-integrity.c | 138 |
1 files changed, 125 insertions, 13 deletions
diff --git a/drivers/md/dm-integrity.c b/drivers/md/dm-integrity.c index 7e48639e4036..46b5d542b8fe 100644 --- a/drivers/md/dm-integrity.c +++ b/drivers/md/dm-integrity.c @@ -40,6 +40,7 @@ #define BITMAP_BLOCK_SIZE 4096 /* don't change it */ #define BITMAP_FLUSH_INTERVAL (10 * HZ) #define DISCARD_FILLER 0xf6 +#define SALT_SIZE 16 /* * Warning - DEBUG_PRINT prints security-sensitive data to the log, @@ -57,6 +58,7 @@ #define SB_VERSION_2 2 #define SB_VERSION_3 3 #define SB_VERSION_4 4 +#define SB_VERSION_5 5 #define SB_SECTORS 8 #define MAX_SECTORS_PER_BLOCK 8 @@ -72,12 +74,15 @@ struct superblock { __u8 log2_blocks_per_bitmap_bit; __u8 pad[2]; __u64 recalc_sector; + __u8 pad2[8]; + __u8 salt[SALT_SIZE]; }; #define SB_FLAG_HAVE_JOURNAL_MAC 0x1 #define SB_FLAG_RECALCULATING 0x2 #define SB_FLAG_DIRTY_BITMAP 0x4 #define SB_FLAG_FIXED_PADDING 0x8 +#define SB_FLAG_FIXED_HMAC 0x10 #define JOURNAL_ENTRY_ROUNDUP 8 @@ -259,6 +264,7 @@ struct dm_integrity_c { bool recalculate_flag; bool discard; bool fix_padding; + bool fix_hmac; bool legacy_recalculate; struct alg_spec internal_hash_alg; @@ -389,8 +395,11 @@ static int dm_integrity_failed(struct dm_integrity_c *ic) static bool dm_integrity_disable_recalculate(struct dm_integrity_c *ic) { - if ((ic->internal_hash_alg.key || ic->journal_mac_alg.key) && - !ic->legacy_recalculate) + if (ic->legacy_recalculate) + return false; + if (!(ic->sb->flags & cpu_to_le32(SB_FLAG_FIXED_HMAC)) ? + ic->internal_hash_alg.key || ic->journal_mac_alg.key : + ic->internal_hash_alg.key && !ic->journal_mac_alg.key) return true; return false; } @@ -477,7 +486,9 @@ static void wraparound_section(struct dm_integrity_c *ic, unsigned *sec_ptr) static void sb_set_version(struct dm_integrity_c *ic) { - if (ic->sb->flags & cpu_to_le32(SB_FLAG_FIXED_PADDING)) + if (ic->sb->flags & cpu_to_le32(SB_FLAG_FIXED_HMAC)) + ic->sb->version = SB_VERSION_5; + else if (ic->sb->flags & cpu_to_le32(SB_FLAG_FIXED_PADDING)) ic->sb->version = SB_VERSION_4; else if (ic->mode == 'B' || ic->sb->flags & cpu_to_le32(SB_FLAG_DIRTY_BITMAP)) ic->sb->version = SB_VERSION_3; @@ -487,10 +498,58 @@ static void sb_set_version(struct dm_integrity_c *ic) ic->sb->version = SB_VERSION_1; } +static int sb_mac(struct dm_integrity_c *ic, bool wr) +{ + SHASH_DESC_ON_STACK(desc, ic->journal_mac); + int r; + unsigned size = crypto_shash_digestsize(ic->journal_mac); + + if (sizeof(struct superblock) + size > 1 << SECTOR_SHIFT) { + dm_integrity_io_error(ic, "digest is too long", -EINVAL); + return -EINVAL; + } + + desc->tfm = ic->journal_mac; + + r = crypto_shash_init(desc); + if (unlikely(r < 0)) { + dm_integrity_io_error(ic, "crypto_shash_init", r); + return r; + } + + r = crypto_shash_update(desc, (__u8 *)ic->sb, (1 << SECTOR_SHIFT) - size); + if (unlikely(r < 0)) { + dm_integrity_io_error(ic, "crypto_shash_update", r); + return r; + } + + if (likely(wr)) { + r = crypto_shash_final(desc, (__u8 *)ic->sb + (1 << SECTOR_SHIFT) - size); + if (unlikely(r < 0)) { + dm_integrity_io_error(ic, "crypto_shash_final", r); + return r; + } + } else { + __u8 result[HASH_MAX_DIGESTSIZE]; + r = crypto_shash_final(desc, result); + if (unlikely(r < 0)) { + dm_integrity_io_error(ic, "crypto_shash_final", r); + return r; + } + if (memcmp((__u8 *)ic->sb + (1 << SECTOR_SHIFT) - size, result, size)) { + dm_integrity_io_error(ic, "superblock mac", -EILSEQ); + return -EILSEQ; + } + } + + return 0; +} + static int sync_rw_sb(struct dm_integrity_c *ic, int op, int op_flags) { struct dm_io_request io_req; struct dm_io_region io_loc; + int r; io_req.bi_op = op; io_req.bi_op_flags = op_flags; @@ -502,10 +561,28 @@ static int sync_rw_sb(struct dm_integrity_c *ic, int op, int op_flags) io_loc.sector = ic->start; io_loc.count = SB_SECTORS; - if (op == REQ_OP_WRITE) + if (op == REQ_OP_WRITE) { sb_set_version(ic); + if (ic->journal_mac && ic->sb->flags & cpu_to_le32(SB_FLAG_FIXED_HMAC)) { + r = sb_mac(ic, true); + if (unlikely(r)) + return r; + } + } - return dm_io(&io_req, 1, &io_loc, NULL); + r = dm_io(&io_req, 1, &io_loc, NULL); + if (unlikely(r)) + return r; + + if (op == REQ_OP_READ) { + if (ic->mode != 'R' && ic->journal_mac && ic->sb->flags & cpu_to_le32(SB_FLAG_FIXED_HMAC)) { + r = sb_mac(ic, false); + if (unlikely(r)) + return r; + } + } + + return 0; } #define BITMAP_OP_TEST_ALL_SET 0 @@ -722,15 +799,32 @@ static void section_mac(struct dm_integrity_c *ic, unsigned section, __u8 result desc->tfm = ic->journal_mac; r = crypto_shash_init(desc); - if (unlikely(r)) { + if (unlikely(r < 0)) { dm_integrity_io_error(ic, "crypto_shash_init", r); goto err; } + if (ic->sb->flags & cpu_to_le32(SB_FLAG_FIXED_HMAC)) { + uint64_t section_le; + + r = crypto_shash_update(desc, (__u8 *)&ic->sb->salt, SALT_SIZE); + if (unlikely(r < 0)) { + dm_integrity_io_error(ic, "crypto_shash_update", r); + goto err; + } + + section_le = cpu_to_le64(section); + r = crypto_shash_update(desc, (__u8 *)§ion_le, sizeof section_le); + if (unlikely(r < 0)) { + dm_integrity_io_error(ic, "crypto_shash_update", r); + goto err; + } + } + for (j = 0; j < ic->journal_section_entries; j++) { struct journal_entry *je = access_journal_entry(ic, section, j); r = crypto_shash_update(desc, (__u8 *)&je->u.sector, sizeof je->u.sector); - if (unlikely(r)) { + if (unlikely(r < 0)) { dm_integrity_io_error(ic, "crypto_shash_update", r); goto err; } @@ -740,7 +834,7 @@ static void section_mac(struct dm_integrity_c *ic, unsigned section, __u8 result if (likely(size <= JOURNAL_MAC_SIZE)) { r = crypto_shash_final(desc, result); - if (unlikely(r)) { + if (unlikely(r < 0)) { dm_integrity_io_error(ic, "crypto_shash_final", r); goto err; } @@ -753,7 +847,7 @@ static void section_mac(struct dm_integrity_c *ic, unsigned section, __u8 result goto err; } r = crypto_shash_final(desc, digest); - if (unlikely(r)) { + if (unlikely(r < 0)) { dm_integrity_io_error(ic, "crypto_shash_final", r); goto err; } @@ -1556,6 +1650,14 @@ static void integrity_sector_checksum(struct dm_integrity_c *ic, sector_t sector goto failed; } + if (ic->sb->flags & cpu_to_le32(SB_FLAG_FIXED_HMAC)) { + r = crypto_shash_update(req, (__u8 *)&ic->sb->salt, SALT_SIZE); + if (unlikely(r < 0)) { + dm_integrity_io_error(ic, "crypto_shash_update", r); + goto failed; + } + } + r = crypto_shash_update(req, (const __u8 *)§or_le, sizeof sector_le); if (unlikely(r < 0)) { dm_integrity_io_error(ic, "crypto_shash_update", r); @@ -3149,6 +3251,7 @@ static void dm_integrity_status(struct dm_target *ti, status_type_t type, arg_count += !!ic->journal_crypt_alg.alg_string; arg_count += !!ic->journal_mac_alg.alg_string; arg_count += (ic->sb->flags & cpu_to_le32(SB_FLAG_FIXED_PADDING)) != 0; + arg_count += (ic->sb->flags & cpu_to_le32(SB_FLAG_FIXED_HMAC)) != 0; arg_count += ic->legacy_recalculate; DMEMIT("%s %llu %u %c %u", ic->dev->name, ic->start, ic->tag_size, ic->mode, arg_count); @@ -3173,6 +3276,8 @@ static void dm_integrity_status(struct dm_target *ti, status_type_t type, } if ((ic->sb->flags & cpu_to_le32(SB_FLAG_FIXED_PADDING)) != 0) DMEMIT(" fix_padding"); + if ((ic->sb->flags & cpu_to_le32(SB_FLAG_FIXED_HMAC)) != 0) + DMEMIT(" fix_hmac"); if (ic->legacy_recalculate) DMEMIT(" legacy_recalculate"); @@ -3310,6 +3415,11 @@ static int initialize_superblock(struct dm_integrity_c *ic, unsigned journal_sec if (!journal_sections) journal_sections = 1; + if (ic->fix_hmac && (ic->internal_hash_alg.alg_string || ic->journal_mac_alg.alg_string)) { + ic->sb->flags |= cpu_to_le32(SB_FLAG_FIXED_HMAC); + get_random_bytes(ic->sb->salt, SALT_SIZE); + } + if (!ic->meta_dev) { if (ic->fix_padding) ic->sb->flags |= cpu_to_le32(SB_FLAG_FIXED_PADDING); @@ -3804,7 +3914,7 @@ static int dm_integrity_ctr(struct dm_target *ti, unsigned argc, char **argv) unsigned extra_args; struct dm_arg_set as; static const struct dm_arg _args[] = { - {0, 16, "Invalid number of feature args"}, + {0, 17, "Invalid number of feature args"}, }; unsigned journal_sectors, interleave_sectors, buffer_sectors, journal_watermark, sync_msec; bool should_write_sb; @@ -3942,7 +4052,7 @@ static int dm_integrity_ctr(struct dm_target *ti, unsigned argc, char **argv) if (r) goto bad; } else if (!strncmp(opt_string, "journal_mac:", strlen("journal_mac:"))) { - r = get_alg_and_key(opt_string, &ic->journal_mac_alg, &ti->error, + r = get_alg_and_key(opt_string, &ic->journal_mac_alg, &ti->error, "Invalid journal_mac argument"); if (r) goto bad; @@ -3952,6 +4062,8 @@ static int dm_integrity_ctr(struct dm_target *ti, unsigned argc, char **argv) ic->discard = true; } else if (!strcmp(opt_string, "fix_padding")) { ic->fix_padding = true; + } else if (!strcmp(opt_string, "fix_hmac")) { + ic->fix_hmac = true; } else if (!strcmp(opt_string, "legacy_recalculate")) { ic->legacy_recalculate = true; } else { @@ -4110,7 +4222,7 @@ static int dm_integrity_ctr(struct dm_target *ti, unsigned argc, char **argv) should_write_sb = true; } - if (!ic->sb->version || ic->sb->version > SB_VERSION_4) { + if (!ic->sb->version || ic->sb->version > SB_VERSION_5) { r = -EINVAL; ti->error = "Unknown version"; goto bad; @@ -4442,7 +4554,7 @@ static void dm_integrity_dtr(struct dm_target *ti) static struct target_type integrity_target = { .name = "integrity", - .version = {1, 6, 0}, + .version = {1, 7, 0}, .module = THIS_MODULE, .features = DM_TARGET_SINGLETON | DM_TARGET_INTEGRITY, .ctr = dm_integrity_ctr, |