crypto: arc4 - convert to skcipher API
authorEric Biggers <ebiggers@google.com>
Fri, 4 Jan 2019 04:16:23 +0000 (20:16 -0800)
committerHerbert Xu <herbert@gondor.apana.org.au>
Fri, 11 Jan 2019 06:16:58 +0000 (14:16 +0800)
Convert the "ecb(arc4)" algorithm from the deprecated "blkcipher" API to
the "skcipher" API.

(Note that this is really a stream cipher and not a block cipher in ECB
mode as the name implies, but that's a problem for another day...)

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
crypto/arc4.c

index f1a8192..652d243 100644 (file)
  *
  */
 
-#include <linux/module.h>
-#include <linux/init.h>
-#include <linux/crypto.h>
 #include <crypto/algapi.h>
+#include <crypto/internal/skcipher.h>
+#include <linux/init.h>
+#include <linux/module.h>
 
 #define ARC4_MIN_KEY_SIZE      1
 #define ARC4_MAX_KEY_SIZE      256
@@ -50,6 +50,12 @@ static int arc4_set_key(struct crypto_tfm *tfm, const u8 *in_key,
        return 0;
 }
 
+static int arc4_set_key_skcipher(struct crypto_skcipher *tfm, const u8 *in_key,
+                                unsigned int key_len)
+{
+       return arc4_set_key(&tfm->base, in_key, key_len);
+}
+
 static void arc4_crypt(struct arc4_ctx *ctx, u8 *out, const u8 *in,
                       unsigned int len)
 {
@@ -92,30 +98,25 @@ static void arc4_crypt_one(struct crypto_tfm *tfm, u8 *out, const u8 *in)
        arc4_crypt(crypto_tfm_ctx(tfm), out, in, 1);
 }
 
-static int ecb_arc4_crypt(struct blkcipher_desc *desc, struct scatterlist *dst,
-                         struct scatterlist *src, unsigned int nbytes)
+static int ecb_arc4_crypt(struct skcipher_request *req)
 {
-       struct arc4_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
-       struct blkcipher_walk walk;
+       struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
+       struct arc4_ctx *ctx = crypto_skcipher_ctx(tfm);
+       struct skcipher_walk walk;
        int err;
 
-       blkcipher_walk_init(&walk, dst, src, nbytes);
-
-       err = blkcipher_walk_virt(desc, &walk);
+       err = skcipher_walk_virt(&walk, req, false);
 
        while (walk.nbytes > 0) {
-               u8 *wsrc = walk.src.virt.addr;
-               u8 *wdst = walk.dst.virt.addr;
-
-               arc4_crypt(ctx, wdst, wsrc, walk.nbytes);
-
-               err = blkcipher_walk_done(desc, &walk, 0);
+               arc4_crypt(ctx, walk.dst.virt.addr, walk.src.virt.addr,
+                          walk.nbytes);
+               err = skcipher_walk_done(&walk, 0);
        }
 
        return err;
 }
 
-static struct crypto_alg arc4_algs[2] = { {
+static struct crypto_alg arc4_cipher = {
        .cra_name               =       "arc4",
        .cra_flags              =       CRYPTO_ALG_TYPE_CIPHER,
        .cra_blocksize          =       ARC4_BLOCK_SIZE,
@@ -130,34 +131,39 @@ static struct crypto_alg arc4_algs[2] = { {
                        .cia_decrypt            =       arc4_crypt_one,
                },
        },
-}, {
-       .cra_name               =       "ecb(arc4)",
-       .cra_priority           =       100,
-       .cra_flags              =       CRYPTO_ALG_TYPE_BLKCIPHER,
-       .cra_blocksize          =       ARC4_BLOCK_SIZE,
-       .cra_ctxsize            =       sizeof(struct arc4_ctx),
-       .cra_alignmask          =       0,
-       .cra_type               =       &crypto_blkcipher_type,
-       .cra_module             =       THIS_MODULE,
-       .cra_u                  =       {
-               .blkcipher = {
-                       .min_keysize    =       ARC4_MIN_KEY_SIZE,
-                       .max_keysize    =       ARC4_MAX_KEY_SIZE,
-                       .setkey         =       arc4_set_key,
-                       .encrypt        =       ecb_arc4_crypt,
-                       .decrypt        =       ecb_arc4_crypt,
-               },
-       },
-} };
+};
+
+static struct skcipher_alg arc4_skcipher = {
+       .base.cra_name          =       "ecb(arc4)",
+       .base.cra_priority      =       100,
+       .base.cra_blocksize     =       ARC4_BLOCK_SIZE,
+       .base.cra_ctxsize       =       sizeof(struct arc4_ctx),
+       .base.cra_module        =       THIS_MODULE,
+       .min_keysize            =       ARC4_MIN_KEY_SIZE,
+       .max_keysize            =       ARC4_MAX_KEY_SIZE,
+       .setkey                 =       arc4_set_key_skcipher,
+       .encrypt                =       ecb_arc4_crypt,
+       .decrypt                =       ecb_arc4_crypt,
+};
 
 static int __init arc4_init(void)
 {
-       return crypto_register_algs(arc4_algs, ARRAY_SIZE(arc4_algs));
+       int err;
+
+       err = crypto_register_alg(&arc4_cipher);
+       if (err)
+               return err;
+
+       err = crypto_register_skcipher(&arc4_skcipher);
+       if (err)
+               crypto_unregister_alg(&arc4_cipher);
+       return err;
 }
 
 static void __exit arc4_exit(void)
 {
-       crypto_unregister_algs(arc4_algs, ARRAY_SIZE(arc4_algs));
+       crypto_unregister_alg(&arc4_cipher);
+       crypto_unregister_skcipher(&arc4_skcipher);
 }
 
 module_init(arc4_init);