[CRYPTO] api: Add async blkcipher type

This patch adds the mid-level interface for asynchronous block ciphers.
It also includes a generic queueing mechanism that can be used by other
asynchronous crypto operations in future.

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

2 files changed, 80 insertions, 0 deletions

diff --git a/include/crypto/algapi.h b/include/crypto/algapi.h
index d0c190b4d02f..469f511315c5 100644
--- a/include/crypto/algapi.h
+++ b/include/crypto/algapi.h
@@ -13,6 +13,8 @@
 #define _CRYPTO_ALGAPI_H
 
 #include <linux/crypto.h>
+#include <linux/list.h>
+#include <linux/kernel.h>
 
 struct module;
 struct rtattr;
@@ -51,6 +53,14 @@ struct crypto_spawn {
         struct crypto_instance *inst;
 };
 
+struct crypto_queue {
+        struct list_head list;
+        struct list_head *backlog;
+
+        unsigned int qlen;
+        unsigned int max_qlen;
+};
+
 struct scatter_walk {
         struct scatterlist *sg;
         unsigned int offset;
@@ -82,6 +92,7 @@ struct blkcipher_walk {
         int flags;
 };
 
+extern const struct crypto_type crypto_ablkcipher_type;
 extern const struct crypto_type crypto_blkcipher_type;
 extern const struct crypto_type crypto_hash_type;
 
@@ -103,6 +114,12 @@ struct crypto_alg *crypto_get_attr_alg(struct rtattr **tb, u32 type, u32 mask);
 struct crypto_instance *crypto_alloc_instance(const char *name,
                                               struct crypto_alg *alg);
 
+void crypto_init_queue(struct crypto_queue *queue, unsigned int max_qlen);
+int crypto_enqueue_request(struct crypto_queue *queue,
+                           struct crypto_async_request *request);
+struct crypto_async_request *crypto_dequeue_request(struct crypto_queue *queue);
+int crypto_tfm_in_queue(struct crypto_queue *queue, struct crypto_tfm *tfm);
+
 int blkcipher_walk_done(struct blkcipher_desc *desc,
                         struct blkcipher_walk *walk, int err);
 int blkcipher_walk_virt(struct blkcipher_desc *desc,
@@ -125,6 +142,17 @@ static inline void *crypto_instance_ctx(struct crypto_instance *inst)
         return inst->__ctx;
 }
 
+static inline struct ablkcipher_alg *crypto_ablkcipher_alg(
+        struct crypto_ablkcipher *tfm)
+{
+        return &crypto_ablkcipher_tfm(tfm)->__crt_alg->cra_ablkcipher;
+}
+
+static inline void *crypto_ablkcipher_ctx(struct crypto_ablkcipher *tfm)
+{
+        return crypto_tfm_ctx(&tfm->base);
+}
+
 static inline void *crypto_blkcipher_ctx(struct crypto_blkcipher *tfm)
 {
         return crypto_tfm_ctx(&tfm->base);
@@ -172,5 +200,35 @@ static inline void blkcipher_walk_init(struct blkcipher_walk *walk,
         walk->total = nbytes;
 }
 
+static inline struct crypto_async_request *crypto_get_backlog(
+        struct crypto_queue *queue)
+{
+        return queue->backlog == &queue->list ? NULL :
+               container_of(queue->backlog, struct crypto_async_request, list);
+}
+
+static inline int ablkcipher_enqueue_request(struct ablkcipher_alg *alg,
+                                             struct ablkcipher_request *request)
+{
+        return crypto_enqueue_request(alg->queue, &request->base);
+}
+
+static inline struct ablkcipher_request *ablkcipher_dequeue_request(
+        struct ablkcipher_alg *alg)
+{
+        return ablkcipher_request_cast(crypto_dequeue_request(alg->queue));
+}
+
+static inline void *ablkcipher_request_ctx(struct ablkcipher_request *req)
+{
+        return req->__ctx;
+}
+
+static inline int ablkcipher_tfm_in_queue(struct crypto_ablkcipher *tfm)
+{
+        return crypto_tfm_in_queue(crypto_ablkcipher_alg(tfm)->queue,
+                                   crypto_ablkcipher_tfm(tfm));
+}
+
 #endif  /* _CRYPTO_ALGAPI_H */
 
diff --git a/include/linux/crypto.h b/include/linux/crypto.h
index 67830e7c2c31..0ec2467891db 100644
--- a/include/linux/crypto.h
+++ b/include/linux/crypto.h
@@ -93,6 +93,7 @@ struct crypto_ablkcipher;
 struct crypto_async_request;
 struct crypto_blkcipher;
 struct crypto_hash;
+struct crypto_queue;
 struct crypto_tfm;
 struct crypto_type;
 
@@ -143,6 +144,19 @@ struct hash_desc {
  * Algorithms: modular crypto algorithm implementations, managed
  * via crypto_register_alg() and crypto_unregister_alg().
  */
+struct ablkcipher_alg {
+        int (*setkey)(struct crypto_ablkcipher *tfm, const u8 *key,
+                      unsigned int keylen);
+        int (*encrypt)(struct ablkcipher_request *req);
+        int (*decrypt)(struct ablkcipher_request *req);
+
+        struct crypto_queue *queue;
+
+        unsigned int min_keysize;
+        unsigned int max_keysize;
+        unsigned int ivsize;
+};
+
 struct blkcipher_alg {
         int (*setkey)(struct crypto_tfm *tfm, const u8 *key,
                       unsigned int keylen);
@@ -197,6 +211,7 @@ struct compress_alg {
                               unsigned int slen, u8 *dst, unsigned int *dlen);
 };
 
+#define cra_ablkcipher  cra_u.ablkcipher
 #define cra_blkcipher   cra_u.blkcipher
 #define cra_cipher      cra_u.cipher
 #define cra_digest      cra_u.digest
@@ -221,6 +236,7 @@ struct crypto_alg {
         const struct crypto_type *cra_type;
 
         union {
+                struct ablkcipher_alg ablkcipher;
                 struct blkcipher_alg blkcipher;
                 struct cipher_alg cipher;
                 struct digest_alg digest;
@@ -572,6 +588,12 @@ static inline int crypto_ablkcipher_reqsize(struct crypto_ablkcipher *tfm)
         return crypto_ablkcipher_crt(tfm)->reqsize;
 }
 
+static inline struct ablkcipher_request *ablkcipher_request_cast(
+        struct crypto_async_request *req)
+{
+        return container_of(req, struct ablkcipher_request, base);
+}
+
 static inline struct ablkcipher_request *ablkcipher_request_alloc(
         struct crypto_ablkcipher *tfm, gfp_t gfp)
 {