[CRYPTO] gcm: Use crypto_grab_skcipher

This patch converts the gcm algorithm over to crypto_grab_skcipher
which is a prerequisite for IV generation.

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

1 files changed, 23 insertions, 26 deletions

diff --git a/crypto/gcm.c b/crypto/gcm.c
index e87e5de8e7b3..d539f5e56879 100644
--- a/crypto/gcm.c
+++ b/crypto/gcm.c
@@ -8,8 +8,8 @@
  * by the Free Software Foundation.
  */
 
-#include <crypto/algapi.h>
 #include <crypto/gf128mul.h>
+#include <crypto/internal/skcipher.h>
 #include <crypto/scatterwalk.h>
 #include <linux/completion.h>
 #include <linux/err.h>
@@ -18,10 +18,8 @@
 #include <linux/module.h>
 #include <linux/slab.h>
 
-#include "internal.h"
-
 struct gcm_instance_ctx {
-        struct crypto_spawn ctr;
+        struct crypto_skcipher_spawn ctr;
 };
 
 struct crypto_gcm_ctx {
@@ -386,7 +384,7 @@ static int crypto_gcm_init_tfm(struct crypto_tfm *tfm)
         unsigned long align;
         int err;
 
-        ctr = crypto_spawn_ablkcipher(&ictx->ctr);
+        ctr = crypto_spawn_skcipher(&ictx->ctr);
         err = PTR_ERR(ctr);
         if (IS_ERR(ctr))
                 return err;
@@ -431,15 +429,22 @@ static struct crypto_instance *crypto_gcm_alloc_common(struct rtattr **tb,
         if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
                 return ERR_PTR(-EINVAL);
 
-        ctr = crypto_alg_mod_lookup(ctr_name, CRYPTO_ALG_TYPE_BLKCIPHER,
-                                    CRYPTO_ALG_TYPE_MASK);
+        inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
+        if (!inst)
+                return ERR_PTR(-ENOMEM);
 
-        if (IS_ERR(ctr))
-                return ERR_PTR(PTR_ERR(ctr));
+        ctx = crypto_instance_ctx(inst);
+        crypto_set_skcipher_spawn(&ctx->ctr, inst);
+        err = crypto_grab_skcipher(&ctx->ctr, ctr_name, 0,
+                                   crypto_requires_sync(algt->type,
+                                                        algt->mask));
+        if (err)
+                goto err_free_inst;
+
+        ctr = crypto_skcipher_spawn_alg(&ctx->ctr);
 
         /* We only support 16-byte blocks. */
-        if ((ctr->cra_type == &crypto_blkcipher_type ?
-             ctr->cra_blkcipher.ivsize : ctr->cra_ablkcipher.ivsize) != 16)
+        if (ctr->cra_ablkcipher.ivsize != 16)
                 goto out_put_ctr;
 
         /* Not a stream cipher? */
@@ -447,25 +452,16 @@ static struct crypto_instance *crypto_gcm_alloc_common(struct rtattr **tb,
         if (ctr->cra_blocksize != 1)
                 goto out_put_ctr;
 
-        inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
-        err = -ENOMEM;
-        if (!inst)
-                goto out_put_ctr;
-
         err = -ENAMETOOLONG;
         if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME,
                      "gcm_base(%s)", ctr->cra_driver_name) >=
             CRYPTO_MAX_ALG_NAME)
-                goto err_free_inst;
-
-        ctx = crypto_instance_ctx(inst);
-        err = crypto_init_spawn(&ctx->ctr, ctr, inst, CRYPTO_ALG_TYPE_MASK);
-        if (err)
-                goto err_free_inst;
+                goto out_put_ctr;
 
         memcpy(inst->alg.cra_name, full_name, CRYPTO_MAX_ALG_NAME);
 
-        inst->alg.cra_flags = CRYPTO_ALG_TYPE_AEAD | CRYPTO_ALG_ASYNC;
+        inst->alg.cra_flags = CRYPTO_ALG_TYPE_AEAD;
+        inst->alg.cra_flags |= ctr->cra_flags & CRYPTO_ALG_ASYNC;
         inst->alg.cra_priority = ctr->cra_priority;
         inst->alg.cra_blocksize = 1;
         inst->alg.cra_alignmask = ctr->cra_alignmask | (__alignof__(u64) - 1);
@@ -480,11 +476,12 @@ static struct crypto_instance *crypto_gcm_alloc_common(struct rtattr **tb,
         inst->alg.cra_aead.decrypt = crypto_gcm_decrypt;
 
 out:
-        crypto_mod_put(ctr);
         return inst;
+
+out_put_ctr:
+        crypto_drop_skcipher(&ctx->ctr);
 err_free_inst:
         kfree(inst);
-out_put_ctr:
         inst = ERR_PTR(err);
         goto out;
 }
@@ -516,7 +513,7 @@ static void crypto_gcm_free(struct crypto_instance *inst)
 {
         struct gcm_instance_ctx *ctx = crypto_instance_ctx(inst);
 
-        crypto_drop_spawn(&ctx->ctr);
+        crypto_drop_skcipher(&ctx->ctr);
         kfree(inst);
 }