[CRYPTO] cipher: Added block cipher type

This patch adds the new type of block ciphers.  Unlike current cipher
algorithms which operate on a single block at a time, block ciphers
operate on an arbitrarily long linear area of data.  As it is block-based,
it will skip any data remaining at the end which cannot form a block.

The block cipher has one major difference when compared to the existing
block cipher implementation.  The sg walking is now performed by the
algorithm rather than the cipher mid-layer.  This is needed for drivers
that directly support sg lists.  It also improves performance for all
algorithms as it reduces the total number of indirect calls by one.

In future the existing cipher algorithm will be converted to only have
a single-block interface.  This will be done after all existing users
have switched over to the new block cipher type.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 65 insertions, 0 deletions

diff --git a/include/crypto/algapi.h b/include/crypto/algapi.h
index f21ae672e8a8..f3946baf0c07 100644
--- a/include/crypto/algapi.h
+++ b/include/crypto/algapi.h
@@ -55,6 +55,34 @@ struct scatter_walk {
         unsigned int offset;
 };
 
+struct blkcipher_walk {
+        union {
+                struct {
+                        struct page *page;
+                        unsigned long offset;
+                } phys;
+
+                struct {
+                        u8 *page;
+                        u8 *addr;
+                } virt;
+        } src, dst;
+
+        struct scatter_walk in;
+        unsigned int nbytes;
+
+        struct scatter_walk out;
+        unsigned int total;
+
+        void *page;
+        u8 *buffer;
+        u8 *iv;
+
+        int flags;
+};
+
+extern const struct crypto_type crypto_blkcipher_type;
+
 int crypto_register_template(struct crypto_template *tmpl);
 void crypto_unregister_template(struct crypto_template *tmpl);
 struct crypto_template *crypto_lookup_template(const char *name);
@@ -69,15 +97,52 @@ struct crypto_alg *crypto_get_attr_alg(void *param, unsigned int len,
 struct crypto_instance *crypto_alloc_instance(const char *name,
                                               struct crypto_alg *alg);
 
+int blkcipher_walk_done(struct blkcipher_desc *desc,
+                        struct blkcipher_walk *walk, int err);
+int blkcipher_walk_virt(struct blkcipher_desc *desc,
+                        struct blkcipher_walk *walk);
+int blkcipher_walk_phys(struct blkcipher_desc *desc,
+                        struct blkcipher_walk *walk);
+
+static inline void *crypto_tfm_ctx_aligned(struct crypto_tfm *tfm)
+{
+        unsigned long addr = (unsigned long)crypto_tfm_ctx(tfm);
+        unsigned long align = crypto_tfm_alg_alignmask(tfm);
+
+        if (align <= crypto_tfm_ctx_alignment())
+                align = 1;
+        return (void *)ALIGN(addr, align);
+}
+
 static inline void *crypto_instance_ctx(struct crypto_instance *inst)
 {
         return inst->__ctx;
 }
 
+static inline void *crypto_blkcipher_ctx(struct crypto_blkcipher *tfm)
+{
+        return crypto_tfm_ctx(&tfm->base);
+}
+
+static inline void *crypto_blkcipher_ctx_aligned(struct crypto_blkcipher *tfm)
+{
+        return crypto_tfm_ctx_aligned(&tfm->base);
+}
+
 static inline struct cipher_alg *crypto_cipher_alg(struct crypto_cipher *tfm)
 {
         return &crypto_cipher_tfm(tfm)->__crt_alg->cra_cipher;
 }
 
+static inline void blkcipher_walk_init(struct blkcipher_walk *walk,
+                                       struct scatterlist *dst,
+                                       struct scatterlist *src,
+                                       unsigned int nbytes)
+{
+        walk->in.sg = src;
+        walk->out.sg = dst;
+        walk->total = nbytes;
+}
+
 #endif  /* _CRYPTO_ALGAPI_H */