1 files changed, 87 insertions, 22 deletions

diff --git a/crypto/arc4.c b/crypto/arc4.c
index 0d12a96da1d8..07913fc52c4e 100644
--- a/crypto/arc4.c
+++ b/crypto/arc4.c
@@ -11,9 +11,11 @@
  * (at your option) any later version.
  *
  */
+
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/crypto.h>
+#include <crypto/algapi.h>
 
 #define ARC4_MIN_KEY_SIZE	1
 #define ARC4_MAX_KEY_SIZE	256
@@ -48,51 +50,114 @@ static int arc4_set_key(struct crypto_tfm *tfm, const u8 *in_key,
 	return 0;
 }
 
-static void arc4_crypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
+static void arc4_crypt(struct arc4_ctx *ctx, u8 *out, const u8 *in,
+		       unsigned int len)
 {
-	struct arc4_ctx *ctx = crypto_tfm_ctx(tfm);
-
 	u8 *const S = ctx->S;
-	u8 x = ctx->x;
-	u8 y = ctx->y;
-	u8 a, b;
+	u8 x, y, a, b;
+	u8 ty, ta, tb;
+
+	if (len == 0)
+		return;
+
+	x = ctx->x;
+	y = ctx->y;
 
 	a = S[x];
 	y = (y + a) & 0xff;
 	b = S[y];
-	S[x] = b;
-	S[y] = a;
-	x = (x + 1) & 0xff;
-	*out++ = *in ^ S[(a + b) & 0xff];
+
+	do {
+		S[y] = a;
+		a = (a + b) & 0xff;
+		S[x] = b;
+		x = (x + 1) & 0xff;
+		ta = S[x];
+		ty = (y + ta) & 0xff;
+		tb = S[ty];
+		*out++ = *in++ ^ S[a];
+		if (--len == 0)
+			break;
+		y = ty;
+		a = ta;
+		b = tb;
+	} while (true);
 
 	ctx->x = x;
 	ctx->y = y;
 }
 
-static struct crypto_alg arc4_alg = {
+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)
+{
+	struct arc4_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
+	struct blkcipher_walk walk;
+	int err;
+
+	blkcipher_walk_init(&walk, dst, src, nbytes);
+
+	err = blkcipher_walk_virt(desc, &walk);
+
+	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);
+	}
+
+	return err;
+}
+
+static struct crypto_alg arc4_algs[2] = { {
 	.cra_name		=	"arc4",
 	.cra_flags		=	CRYPTO_ALG_TYPE_CIPHER,
 	.cra_blocksize		=	ARC4_BLOCK_SIZE,
 	.cra_ctxsize		=	sizeof(struct arc4_ctx),
 	.cra_module		=	THIS_MODULE,
-	.cra_list		=	LIST_HEAD_INIT(arc4_alg.cra_list),
-	.cra_u			=	{ .cipher = {
-	.cia_min_keysize	=	ARC4_MIN_KEY_SIZE,
-	.cia_max_keysize	=	ARC4_MAX_KEY_SIZE,
-	.cia_setkey		=	arc4_set_key,
-	.cia_encrypt		=	arc4_crypt,
-	.cia_decrypt		=	arc4_crypt } }
-};
+	.cra_u			=	{
+		.cipher = {
+			.cia_min_keysize	=	ARC4_MIN_KEY_SIZE,
+			.cia_max_keysize	=	ARC4_MAX_KEY_SIZE,
+			.cia_setkey		=	arc4_set_key,
+			.cia_encrypt		=	arc4_crypt_one,
+			.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 int __init arc4_init(void)
 {
-	return crypto_register_alg(&arc4_alg);
+	return crypto_register_algs(arc4_algs, ARRAY_SIZE(arc4_algs));
 }
 
-
 static void __exit arc4_exit(void)
 {
-	crypto_unregister_alg(&arc4_alg);
+	crypto_unregister_algs(arc4_algs, ARRAY_SIZE(arc4_algs));
 }
 
 module_init(arc4_init);