crypto: x86/twofish-3way - remove LRW algorithm

The LRW template now wraps an ECB mode algorithm rather than the block
cipher directly.  Therefore it is now redundant for crypto modules to
wrap their ECB code with generic LRW code themselves via lrw_crypt().

Remove the lrw-twofish-3way algorithm which did this.  Users who request
lrw(twofish) and previously would have gotten lrw-twofish-3way will now
get lrw(ecb-twofish-3way) instead, which is just as fast.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

arch/x86/crypto/twofish_avx_glue.c

@@ -262,6 +262,32 @@ static void decrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes)
 		twofish_dec_blk(ctx->ctx, srcdst, srcdst);
 }
 
+struct twofish_lrw_ctx {
+	struct lrw_table_ctx lrw_table;
+	struct twofish_ctx twofish_ctx;
+};
+
+static int lrw_twofish_setkey(struct crypto_tfm *tfm, const u8 *key,
+			      unsigned int keylen)
+{
+	struct twofish_lrw_ctx *ctx = crypto_tfm_ctx(tfm);
+	int err;
+
+	err = __twofish_setkey(&ctx->twofish_ctx, key, keylen - TF_BLOCK_SIZE,
+			       &tfm->crt_flags);
+	if (err)
+		return err;
+
+	return lrw_init_table(&ctx->lrw_table, key + keylen - TF_BLOCK_SIZE);
+}
+
+static void lrw_twofish_exit_tfm(struct crypto_tfm *tfm)
+{
+	struct twofish_lrw_ctx *ctx = crypto_tfm_ctx(tfm);
+
+	lrw_free_table(&ctx->lrw_table);
+}
+
 static int lrw_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
 		       struct scatterlist *src, unsigned int nbytes)
 {

arch/x86/crypto/twofish_glue_3way.c

@@ -30,7 +30,6 @@
 #include <crypto/b128ops.h>
 #include <asm/crypto/twofish.h>
 #include <asm/crypto/glue_helper.h>
-#include <crypto/lrw.h>
 #include <crypto/xts.h>
 
 EXPORT_SYMBOL_GPL(__twofish_enc_blk_3way);
@@ -213,63 +212,6 @@ static void decrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes)
 		twofish_dec_blk(ctx, srcdst, srcdst);
 }
 
-int lrw_twofish_setkey(struct crypto_tfm *tfm, const u8 *key,
-		       unsigned int keylen)
-{
-	struct twofish_lrw_ctx *ctx = crypto_tfm_ctx(tfm);
-	int err;
-
-	err = __twofish_setkey(&ctx->twofish_ctx, key, keylen - TF_BLOCK_SIZE,
-			       &tfm->crt_flags);
-	if (err)
-		return err;
-
-	return lrw_init_table(&ctx->lrw_table, key + keylen - TF_BLOCK_SIZE);
-}
-EXPORT_SYMBOL_GPL(lrw_twofish_setkey);
-
-static int lrw_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
-		       struct scatterlist *src, unsigned int nbytes)
-{
-	struct twofish_lrw_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
-	be128 buf[3];
-	struct lrw_crypt_req req = {
-		.tbuf = buf,
-		.tbuflen = sizeof(buf),
-
-		.table_ctx = &ctx->lrw_table,
-		.crypt_ctx = &ctx->twofish_ctx,
-		.crypt_fn = encrypt_callback,
-	};
-
-	return lrw_crypt(desc, dst, src, nbytes, &req);
-}
-
-static int lrw_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
-		       struct scatterlist *src, unsigned int nbytes)
-{
-	struct twofish_lrw_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
-	be128 buf[3];
-	struct lrw_crypt_req req = {
-		.tbuf = buf,
-		.tbuflen = sizeof(buf),
-
-		.table_ctx = &ctx->lrw_table,
-		.crypt_ctx = &ctx->twofish_ctx,
-		.crypt_fn = decrypt_callback,
-	};
-
-	return lrw_crypt(desc, dst, src, nbytes, &req);
-}
-
-void lrw_twofish_exit_tfm(struct crypto_tfm *tfm)
-{
-	struct twofish_lrw_ctx *ctx = crypto_tfm_ctx(tfm);
-
-	lrw_free_table(&ctx->lrw_table);
-}
-EXPORT_SYMBOL_GPL(lrw_twofish_exit_tfm);
-
 int xts_twofish_setkey(struct crypto_tfm *tfm, const u8 *key,
 		       unsigned int keylen)
 {
@@ -328,7 +270,7 @@ static int xts_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
 	return xts_crypt(desc, dst, src, nbytes, &req);
 }
 
-static struct crypto_alg tf_algs[5] = { {
+static struct crypto_alg tf_algs[] = { {
 	.cra_name		= "ecb(twofish)",
 	.cra_driver_name	= "ecb-twofish-3way",
 	.cra_priority		= 300,
@@ -387,27 +329,6 @@ static struct crypto_alg tf_algs[5] = { {
 			.decrypt	= ctr_crypt,
 		},
 	},
-}, {
-	.cra_name		= "lrw(twofish)",
-	.cra_driver_name	= "lrw-twofish-3way",
-	.cra_priority		= 300,
-	.cra_flags		= CRYPTO_ALG_TYPE_BLKCIPHER,
-	.cra_blocksize		= TF_BLOCK_SIZE,
-	.cra_ctxsize		= sizeof(struct twofish_lrw_ctx),
-	.cra_alignmask		= 0,
-	.cra_type		= &crypto_blkcipher_type,
-	.cra_module		= THIS_MODULE,
-	.cra_exit		= lrw_twofish_exit_tfm,
-	.cra_u = {
-		.blkcipher = {
-			.min_keysize	= TF_MIN_KEY_SIZE + TF_BLOCK_SIZE,
-			.max_keysize	= TF_MAX_KEY_SIZE + TF_BLOCK_SIZE,
-			.ivsize		= TF_BLOCK_SIZE,
-			.setkey		= lrw_twofish_setkey,
-			.encrypt	= lrw_encrypt,
-			.decrypt	= lrw_decrypt,
-		},
-	},
 }, {
 	.cra_name		= "xts(twofish)",
 	.cra_driver_name	= "xts-twofish-3way",

arch/x86/include/asm/crypto/twofish.h

@@ -4,14 +4,8 @@
 
 #include <linux/crypto.h>
 #include <crypto/twofish.h>
-#include <crypto/lrw.h>
 #include <crypto/b128ops.h>
 
-struct twofish_lrw_ctx {
-	struct lrw_table_ctx lrw_table;
-	struct twofish_ctx twofish_ctx;
-};
-
 struct twofish_xts_ctx {
 	struct twofish_ctx tweak_ctx;
 	struct twofish_ctx crypt_ctx;
@@ -36,11 +30,6 @@ extern void twofish_enc_blk_ctr(void *ctx, u128 *dst, const u128 *src,
 extern void twofish_enc_blk_ctr_3way(void *ctx, u128 *dst, const u128 *src,
 				     le128 *iv);
 
-extern int lrw_twofish_setkey(struct crypto_tfm *tfm, const u8 *key,
-			      unsigned int keylen);
-
-extern void lrw_twofish_exit_tfm(struct crypto_tfm *tfm);
-
 extern int xts_twofish_setkey(struct crypto_tfm *tfm, const u8 *key,
 			      unsigned int keylen);
 

crypto/Kconfig

@@ -1584,7 +1584,6 @@ config CRYPTO_TWOFISH_X86_64_3WAY
 	select CRYPTO_TWOFISH_COMMON
 	select CRYPTO_TWOFISH_X86_64
 	select CRYPTO_GLUE_HELPER_X86
-	select CRYPTO_LRW
 	select CRYPTO_XTS
 	help
 	  Twofish cipher algorithm (x86_64, 3-way parallel).