crypto: skcipher - Add low-level skcipher interface

This patch allows skcipher algorithms and instances to be created
and registered with the crypto API.  They are accessible through
the top-level skcipher interface, along with ablkcipher/blkcipher
algorithms and instances.

This patch also introduces a new parameter called chunk size
which is meant for ciphers such as CTR and CTS which ostensibly
can handle arbitrary lengths, but still behave like block ciphers
in that you can only process a partial block at the very end.

For these ciphers the block size will continue to be set to 1
as it is now while the chunk size will be set to the underlying
block size.

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

1 files changed, 87 insertions, 0 deletions

diff --git a/include/crypto/internal/skcipher.h b/include/crypto/internal/skcipher.h
index 2cf7a61ece59..ce6619c339fe 100644
--- a/include/crypto/internal/skcipher.h
+++ b/include/crypto/internal/skcipher.h
@@ -19,12 +19,46 @@
 
 struct rtattr;
 
+struct skcipher_instance {
+        void (*free)(struct skcipher_instance *inst);
+        union {
+                struct {
+                        char head[offsetof(struct skcipher_alg, base)];
+                        struct crypto_instance base;
+                } s;
+                struct skcipher_alg alg;
+        };
+};
+
 struct crypto_skcipher_spawn {
         struct crypto_spawn base;
 };
 
 extern const struct crypto_type crypto_givcipher_type;
 
+static inline struct crypto_instance *skcipher_crypto_instance(
+        struct skcipher_instance *inst)
+{
+        return &inst->s.base;
+}
+
+static inline struct skcipher_instance *skcipher_alg_instance(
+        struct crypto_skcipher *skcipher)
+{
+        return container_of(crypto_skcipher_alg(skcipher),
+                            struct skcipher_instance, alg);
+}
+
+static inline void *skcipher_instance_ctx(struct skcipher_instance *inst)
+{
+        return crypto_instance_ctx(skcipher_crypto_instance(inst));
+}
+
+static inline void skcipher_request_complete(struct skcipher_request *req, int err)
+{
+        req->base.complete(&req->base, err);
+}
+
 static inline void crypto_set_skcipher_spawn(
         struct crypto_skcipher_spawn *spawn, struct crypto_instance *inst)
 {
@@ -33,6 +67,8 @@ static inline void crypto_set_skcipher_spawn(
 
 int crypto_grab_skcipher(struct crypto_skcipher_spawn *spawn, const char *name,
                          u32 type, u32 mask);
+int crypto_grab_skcipher2(struct crypto_skcipher_spawn *spawn,
+                          const char *name, u32 type, u32 mask);
 
 struct crypto_alg *crypto_lookup_skcipher(const char *name, u32 type, u32 mask);
 
@@ -47,6 +83,12 @@ static inline struct crypto_alg *crypto_skcipher_spawn_alg(
         return spawn->base.alg;
 }
 
+static inline struct skcipher_alg *crypto_spawn_skcipher_alg(
+        struct crypto_skcipher_spawn *spawn)
+{
+        return container_of(spawn->base.alg, struct skcipher_alg, base);
+}
+
 static inline struct crypto_ablkcipher *crypto_spawn_skcipher(
         struct crypto_skcipher_spawn *spawn)
 {
@@ -55,6 +97,25 @@ static inline struct crypto_ablkcipher *crypto_spawn_skcipher(
                                  crypto_skcipher_mask(0)));
 }
 
+static inline struct crypto_skcipher *crypto_spawn_skcipher2(
+        struct crypto_skcipher_spawn *spawn)
+{
+        return crypto_spawn_tfm2(&spawn->base);
+}
+
+static inline void crypto_skcipher_set_reqsize(
+        struct crypto_skcipher *skcipher, unsigned int reqsize)
+{
+        skcipher->reqsize = reqsize;
+}
+
+int crypto_register_skcipher(struct skcipher_alg *alg);
+void crypto_unregister_skcipher(struct skcipher_alg *alg);
+int crypto_register_skciphers(struct skcipher_alg *algs, int count);
+void crypto_unregister_skciphers(struct skcipher_alg *algs, int count);
+int skcipher_register_instance(struct crypto_template *tmpl,
+                               struct skcipher_instance *inst);
+
 int skcipher_null_givencrypt(struct skcipher_givcrypt_request *req);
 int skcipher_null_givdecrypt(struct skcipher_givcrypt_request *req);
 const char *crypto_default_geniv(const struct crypto_alg *alg);
@@ -122,5 +183,31 @@ static inline u32 skcipher_request_flags(struct skcipher_request *req)
         return req->base.flags;
 }
 
+static inline unsigned int crypto_skcipher_alg_min_keysize(
+        struct skcipher_alg *alg)
+{
+        if ((alg->base.cra_flags & CRYPTO_ALG_TYPE_MASK) ==
+            CRYPTO_ALG_TYPE_BLKCIPHER)
+                return alg->base.cra_blkcipher.min_keysize;
+
+        if (alg->base.cra_ablkcipher.encrypt)
+                return alg->base.cra_ablkcipher.min_keysize;
+
+        return alg->min_keysize;
+}
+
+static inline unsigned int crypto_skcipher_alg_max_keysize(
+        struct skcipher_alg *alg)
+{
+        if ((alg->base.cra_flags & CRYPTO_ALG_TYPE_MASK) ==
+            CRYPTO_ALG_TYPE_BLKCIPHER)
+                return alg->base.cra_blkcipher.max_keysize;
+
+        if (alg->base.cra_ablkcipher.encrypt)
+                return alg->base.cra_ablkcipher.max_keysize;
+
+        return alg->max_keysize;
+}
+
 #endif  /* _CRYPTO_INTERNAL_SKCIPHER_H */