[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 <herbert@gondor.apana.org.au>
This commit is contained in:
Herbert Xu 2007-10-04 15:24:05 +08:00 committed by David S. Miller
parent 2614de1b9a
commit 7607bd8ff0
2 changed files with 28 additions and 10 deletions

View File

@ -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)
{

View File

@ -91,6 +91,7 @@ struct blkcipher_walk {
u8 *iv;
int flags;
unsigned int blocksize;
};
extern const struct crypto_type crypto_ablkcipher_type;
@ -129,6 +130,9 @@ int blkcipher_walk_virt(struct blkcipher_desc *desc,
struct blkcipher_walk *walk);
int blkcipher_walk_phys(struct blkcipher_desc *desc,
struct blkcipher_walk *walk);
int blkcipher_walk_virt_block(struct blkcipher_desc *desc,
struct blkcipher_walk *walk,
unsigned int blocksize);
static inline void *crypto_tfm_ctx_aligned(struct crypto_tfm *tfm)
{