[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>

1 files changed, 4 insertions, 0 deletions

diff --git a/include/crypto/algapi.h b/include/crypto/algapi.h
index 4af72dc21202..b9b05d399d2b 100644
--- a/include/crypto/algapi.h
+++ b/include/crypto/algapi.h
@@ -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)
 {