From 7607bd8ff03b8af5af887931318cb2bb20361856 Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Thu, 4 Oct 2007 15:24:05 +0800 Subject: [CRYPTO] blkcipher: Added blkcipher_walk_virt_block This patch adds the helper blkcipher_walk_virt_block which is similar to blkcipher_walk_virt but uses a supplied block size instead of the block size of the block cipher. This is useful for CTR where the block size is 1 but we still want to walk by the block size of the underlying cipher. Signed-off-by: Herbert Xu --- crypto/blkcipher.c | 34 ++++++++++++++++++++++++---------- 1 file changed, 24 insertions(+), 10 deletions(-) (limited to 'crypto/blkcipher.c') diff --git a/crypto/blkcipher.c b/crypto/blkcipher.c index 3d05586a8f34..f6c67f9d4e5c 100644 --- a/crypto/blkcipher.c +++ b/crypto/blkcipher.c @@ -84,8 +84,6 @@ static inline unsigned int blkcipher_done_slow(struct crypto_blkcipher *tfm, static inline unsigned int blkcipher_done_fast(struct blkcipher_walk *walk, unsigned int n) { - n = walk->nbytes - n; - if (walk->flags & BLKCIPHER_WALK_COPY) { blkcipher_map_dst(walk); memcpy(walk->dst.virt.addr, walk->page, n); @@ -109,13 +107,15 @@ int blkcipher_walk_done(struct blkcipher_desc *desc, unsigned int nbytes = 0; if (likely(err >= 0)) { - unsigned int bsize = crypto_blkcipher_blocksize(tfm); - unsigned int n; + unsigned int n = walk->nbytes - err; if (likely(!(walk->flags & BLKCIPHER_WALK_SLOW))) - n = blkcipher_done_fast(walk, err); - else - n = blkcipher_done_slow(tfm, walk, bsize); + n = blkcipher_done_fast(walk, n); + else if (WARN_ON(err)) { + err = -EINVAL; + goto err; + } else + n = blkcipher_done_slow(tfm, walk, n); nbytes = walk->total - n; err = 0; @@ -132,6 +132,7 @@ int blkcipher_walk_done(struct blkcipher_desc *desc, return blkcipher_walk_next(desc, walk); } +err: if (walk->iv != desc->info) memcpy(desc->info, walk->iv, crypto_blkcipher_ivsize(tfm)); if (walk->buffer != walk->page) @@ -225,12 +226,12 @@ static int blkcipher_walk_next(struct blkcipher_desc *desc, { struct crypto_blkcipher *tfm = desc->tfm; unsigned int alignmask = crypto_blkcipher_alignmask(tfm); - unsigned int bsize = crypto_blkcipher_blocksize(tfm); + unsigned int bsize; unsigned int n; int err; n = walk->total; - if (unlikely(n < bsize)) { + if (unlikely(n < crypto_blkcipher_blocksize(tfm))) { desc->flags |= CRYPTO_TFM_RES_BAD_BLOCK_LEN; return blkcipher_walk_done(desc, walk, -EINVAL); } @@ -247,6 +248,7 @@ static int blkcipher_walk_next(struct blkcipher_desc *desc, } } + bsize = min(walk->blocksize, n); n = scatterwalk_clamp(&walk->in, n); n = scatterwalk_clamp(&walk->out, n); @@ -277,7 +279,7 @@ static inline int blkcipher_copy_iv(struct blkcipher_walk *walk, struct crypto_blkcipher *tfm, unsigned int alignmask) { - unsigned bs = crypto_blkcipher_blocksize(tfm); + unsigned bs = walk->blocksize; unsigned int ivsize = crypto_blkcipher_ivsize(tfm); unsigned aligned_bs = ALIGN(bs, alignmask + 1); unsigned int size = aligned_bs * 2 + ivsize + max(aligned_bs, ivsize) - @@ -302,6 +304,7 @@ int blkcipher_walk_virt(struct blkcipher_desc *desc, struct blkcipher_walk *walk) { walk->flags &= ~BLKCIPHER_WALK_PHYS; + walk->blocksize = crypto_blkcipher_blocksize(desc->tfm); return blkcipher_walk_first(desc, walk); } EXPORT_SYMBOL_GPL(blkcipher_walk_virt); @@ -310,6 +313,7 @@ int blkcipher_walk_phys(struct blkcipher_desc *desc, struct blkcipher_walk *walk) { walk->flags |= BLKCIPHER_WALK_PHYS; + walk->blocksize = crypto_blkcipher_blocksize(desc->tfm); return blkcipher_walk_first(desc, walk); } EXPORT_SYMBOL_GPL(blkcipher_walk_phys); @@ -342,6 +346,16 @@ static int blkcipher_walk_first(struct blkcipher_desc *desc, return blkcipher_walk_next(desc, walk); } +int blkcipher_walk_virt_block(struct blkcipher_desc *desc, + struct blkcipher_walk *walk, + unsigned int blocksize) +{ + walk->flags &= ~BLKCIPHER_WALK_PHYS; + walk->blocksize = blocksize; + return blkcipher_walk_first(desc, walk); +} +EXPORT_SYMBOL_GPL(blkcipher_walk_virt_block); + static int setkey_unaligned(struct crypto_tfm *tfm, const u8 *key, unsigned int keylen) { -- cgit v1.2.3-70-g09d2