1 files changed, 40 insertions, 65 deletions

diff --git a/arch/x86/crypto/salsa20_glue.c b/arch/x86/crypto/salsa20_glue.c
index cb91a64a99e7..b07d7d959806 100644
--- a/arch/x86/crypto/salsa20_glue.c
+++ b/arch/x86/crypto/salsa20_glue.c
@@ -11,6 +11,9 @@
  * - x86-64 version, renamed as salsa20-x86_64-asm_64.S
  *   available from <http://cr.yp.to/snuffle/salsa20/amd64-3/salsa20.s>
  *
+ * Also modified to set up the initial state using the generic C code rather
+ * than in assembly.
+ *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License as published by the Free
  * Software Foundation; either version 2 of the License, or (at your option)
@@ -18,93 +21,65 @@
  *
  */
 
-#include <crypto/algapi.h>
+#include <asm/unaligned.h>
+#include <crypto/internal/skcipher.h>
+#include <crypto/salsa20.h>
 #include <linux/module.h>
-#include <linux/crypto.h>
-
-#define SALSA20_IV_SIZE        8U
-#define SALSA20_MIN_KEY_SIZE  16U
-#define SALSA20_MAX_KEY_SIZE  32U
-
-struct salsa20_ctx
-{
-	u32 input[16];
-};
 
-asmlinkage void salsa20_keysetup(struct salsa20_ctx *ctx, const u8 *k,
-				 u32 keysize, u32 ivsize);
-asmlinkage void salsa20_ivsetup(struct salsa20_ctx *ctx, const u8 *iv);
-asmlinkage void salsa20_encrypt_bytes(struct salsa20_ctx *ctx,
-				      const u8 *src, u8 *dst, u32 bytes);
+asmlinkage void salsa20_encrypt_bytes(u32 state[16], const u8 *src, u8 *dst,
+				      u32 bytes);
 
-static int setkey(struct crypto_tfm *tfm, const u8 *key,
-		  unsigned int keysize)
+static int salsa20_asm_crypt(struct skcipher_request *req)
 {
-	struct salsa20_ctx *ctx = crypto_tfm_ctx(tfm);
-	salsa20_keysetup(ctx, key, keysize*8, SALSA20_IV_SIZE*8);
-	return 0;
-}
-
-static int encrypt(struct blkcipher_desc *desc,
-		   struct scatterlist *dst, struct scatterlist *src,
-		   unsigned int nbytes)
-{
-	struct blkcipher_walk walk;
-	struct crypto_blkcipher *tfm = desc->tfm;
-	struct salsa20_ctx *ctx = crypto_blkcipher_ctx(tfm);
+	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
+	const struct salsa20_ctx *ctx = crypto_skcipher_ctx(tfm);
+	struct skcipher_walk walk;
+	u32 state[16];
 	int err;
 
-	blkcipher_walk_init(&walk, dst, src, nbytes);
-	err = blkcipher_walk_virt_block(desc, &walk, 64);
+	err = skcipher_walk_virt(&walk, req, true);
 
-	salsa20_ivsetup(ctx, walk.iv);
+	crypto_salsa20_init(state, ctx, walk.iv);
 
-	while (walk.nbytes >= 64) {
-		salsa20_encrypt_bytes(ctx, walk.src.virt.addr,
-				      walk.dst.virt.addr,
-				      walk.nbytes - (walk.nbytes % 64));
-		err = blkcipher_walk_done(desc, &walk, walk.nbytes % 64);
-	}
+	while (walk.nbytes > 0) {
+		unsigned int nbytes = walk.nbytes;
 
-	if (walk.nbytes) {
-		salsa20_encrypt_bytes(ctx, walk.src.virt.addr,
-				      walk.dst.virt.addr, walk.nbytes);
-		err = blkcipher_walk_done(desc, &walk, 0);
+		if (nbytes < walk.total)
+			nbytes = round_down(nbytes, walk.stride);
+
+		salsa20_encrypt_bytes(state, walk.src.virt.addr,
+				      walk.dst.virt.addr, nbytes);
+		err = skcipher_walk_done(&walk, walk.nbytes - nbytes);
 	}
 
 	return err;
 }
 
-static struct crypto_alg alg = {
-	.cra_name           =   "salsa20",
-	.cra_driver_name    =   "salsa20-asm",
-	.cra_priority       =   200,
-	.cra_flags          =   CRYPTO_ALG_TYPE_BLKCIPHER,
-	.cra_type           =   &crypto_blkcipher_type,
-	.cra_blocksize      =   1,
-	.cra_ctxsize        =   sizeof(struct salsa20_ctx),
-	.cra_alignmask      =	3,
-	.cra_module         =   THIS_MODULE,
-	.cra_u              =   {
-		.blkcipher = {
-			.setkey         =   setkey,
-			.encrypt        =   encrypt,
-			.decrypt        =   encrypt,
-			.min_keysize    =   SALSA20_MIN_KEY_SIZE,
-			.max_keysize    =   SALSA20_MAX_KEY_SIZE,
-			.ivsize         =   SALSA20_IV_SIZE,
-		}
-	}
+static struct skcipher_alg alg = {
+	.base.cra_name		= "salsa20",
+	.base.cra_driver_name	= "salsa20-asm",
+	.base.cra_priority	= 200,
+	.base.cra_blocksize	= 1,
+	.base.cra_ctxsize	= sizeof(struct salsa20_ctx),
+	.base.cra_module	= THIS_MODULE,
+
+	.min_keysize		= SALSA20_MIN_KEY_SIZE,
+	.max_keysize		= SALSA20_MAX_KEY_SIZE,
+	.ivsize			= SALSA20_IV_SIZE,
+	.chunksize		= SALSA20_BLOCK_SIZE,
+	.setkey			= crypto_salsa20_setkey,
+	.encrypt		= salsa20_asm_crypt,
+	.decrypt		= salsa20_asm_crypt,
 };
 
 static int __init init(void)
 {
-	return crypto_register_alg(&alg);
+	return crypto_register_skcipher(&alg);
 }
 
 static void __exit fini(void)
 {
-	crypto_unregister_alg(&alg);
+	crypto_unregister_skcipher(&alg);
 }
 
 module_init(init);