From 070bb43ab01e891db1b742d4ddd7291c7f8d7022 Mon Sep 17 00:00:00 2001 From: Eric Biggers Date: Sat, 28 Oct 2023 21:59:44 -0700 Subject: dm integrity: use crypto_shash_digest() in sb_mac() Simplify sb_mac() by using crypto_shash_digest() instead of an init+update+final sequence. This should also improve performance. Signed-off-by: Eric Biggers Signed-off-by: Mike Snitzer --- drivers/md/dm-integrity.c | 30 ++++++++++-------------------- 1 file changed, 10 insertions(+), 20 deletions(-) (limited to 'drivers/md/dm-integrity.c') diff --git a/drivers/md/dm-integrity.c b/drivers/md/dm-integrity.c index 97a8d5fc9ebb..e85c688fd91e 100644 --- a/drivers/md/dm-integrity.c +++ b/drivers/md/dm-integrity.c @@ -493,42 +493,32 @@ static int sb_mac(struct dm_integrity_c *ic, bool wr) { SHASH_DESC_ON_STACK(desc, ic->journal_mac); int r; - unsigned int size = crypto_shash_digestsize(ic->journal_mac); + unsigned int mac_size = crypto_shash_digestsize(ic->journal_mac); + __u8 *sb = (__u8 *)ic->sb; + __u8 *mac = sb + (1 << SECTOR_SHIFT) - mac_size; - if (sizeof(struct superblock) + size > 1 << SECTOR_SHIFT) { + if (sizeof(struct superblock) + mac_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); + r = crypto_shash_digest(desc, sb, mac - sb, mac); if (unlikely(r < 0)) { - dm_integrity_io_error(ic, "crypto_shash_final", r); + dm_integrity_io_error(ic, "crypto_shash_digest", r); return r; } } else { - __u8 result[HASH_MAX_DIGESTSIZE]; + __u8 actual_mac[HASH_MAX_DIGESTSIZE]; - r = crypto_shash_final(desc, result); + r = crypto_shash_digest(desc, sb, mac - sb, actual_mac); if (unlikely(r < 0)) { - dm_integrity_io_error(ic, "crypto_shash_final", r); + dm_integrity_io_error(ic, "crypto_shash_digest", r); return r; } - if (memcmp((__u8 *)ic->sb + (1 << SECTOR_SHIFT) - size, result, size)) { + if (memcmp(mac, actual_mac, mac_size)) { dm_integrity_io_error(ic, "superblock mac", -EILSEQ); dm_audit_log_target(DM_MSG_PREFIX, "mac-superblock", ic->ti, 0); return -EILSEQ; -- cgit