From: Herbert Xu Subject: [PATCH 2/5] [CRYPTO] cbc: Use crypto_xor Date: Thu, 22 Nov 2007 16:37:46 +0800 Message-ID: References: <20071122083656.GB7368@gondor.apana.org.au> To: Linux Crypto Mailing List Return-path: Received: from rhun.apana.org.au ([64.62.148.172]:4621 "EHLO arnor.apana.org.au" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751073AbXKVIsG (ORCPT ); Thu, 22 Nov 2007 03:48:06 -0500 Received: from gondolin.me.apana.org.au ([192.168.0.6] ident=mail) by arnor.apana.org.au with esmtp (Exim 4.50 #1 (Debian)) id 1Iv7j7-0008A8-N9 for ; Thu, 22 Nov 2007 19:48:02 +1100 Sender: linux-crypto-owner@vger.kernel.org List-Id: linux-crypto.vger.kernel.org [CRYPTO] cbc: Use crypto_xor This patch replaces the custom xor in CBC with the generic crypto_xor. Signed-off-by: Herbert Xu --- crypto/cbc.c | 93 ++++++++++------------------------------------------------- 1 files changed, 16 insertions(+), 77 deletions(-) diff --git a/crypto/cbc.c b/crypto/cbc.c index 1f2649e..b013d6f 100644 --- a/crypto/cbc.c +++ b/crypto/cbc.c @@ -20,7 +20,6 @@ struct crypto_cbc_ctx { struct crypto_cipher *child; - void (*xor)(u8 *dst, const u8 *src, unsigned int bs); }; static int crypto_cbc_setkey(struct crypto_tfm *parent, const u8 *key, @@ -41,9 +40,7 @@ static int crypto_cbc_setkey(struct crypto_tfm *parent, const u8 *key, static int crypto_cbc_encrypt_segment(struct blkcipher_desc *desc, struct blkcipher_walk *walk, - struct crypto_cipher *tfm, - void (*xor)(u8 *, const u8 *, - unsigned int)) + struct crypto_cipher *tfm) { void (*fn)(struct crypto_tfm *, u8 *, const u8 *) = crypto_cipher_alg(tfm)->cia_encrypt; @@ -54,7 +51,7 @@ static int crypto_cbc_encrypt_segment(struct blkcipher_desc *desc, u8 *iv = walk->iv; do { - xor(iv, src, bsize); + crypto_xor(iv, src, bsize); fn(crypto_cipher_tfm(tfm), dst, iv); memcpy(iv, dst, bsize); @@ -67,9 +64,7 @@ static int crypto_cbc_encrypt_segment(struct blkcipher_desc *desc, static int crypto_cbc_encrypt_inplace(struct blkcipher_desc *desc, struct blkcipher_walk *walk, - struct crypto_cipher *tfm, - void (*xor)(u8 *, const u8 *, - unsigned int)) + struct crypto_cipher *tfm) { void (*fn)(struct crypto_tfm *, u8 *, const u8 *) = crypto_cipher_alg(tfm)->cia_encrypt; @@ -79,7 +74,7 @@ static int crypto_cbc_encrypt_inplace(struct blkcipher_desc *desc, u8 *iv = walk->iv; do { - xor(src, iv, bsize); + crypto_xor(src, iv, bsize); fn(crypto_cipher_tfm(tfm), src, src); iv = src; @@ -99,7 +94,6 @@ static int crypto_cbc_encrypt(struct blkcipher_desc *desc, struct crypto_blkcipher *tfm = desc->tfm; struct crypto_cbc_ctx *ctx = crypto_blkcipher_ctx(tfm); struct crypto_cipher *child = ctx->child; - void (*xor)(u8 *, const u8 *, unsigned int bs) = ctx->xor; int err; blkcipher_walk_init(&walk, dst, src, nbytes); @@ -107,11 +101,9 @@ static int crypto_cbc_encrypt(struct blkcipher_desc *desc, while ((nbytes = walk.nbytes)) { if (walk.src.virt.addr == walk.dst.virt.addr) - nbytes = crypto_cbc_encrypt_inplace(desc, &walk, child, - xor); + nbytes = crypto_cbc_encrypt_inplace(desc, &walk, child); else - nbytes = crypto_cbc_encrypt_segment(desc, &walk, child, - xor); + nbytes = crypto_cbc_encrypt_segment(desc, &walk, child); err = blkcipher_walk_done(desc, &walk, nbytes); } @@ -120,9 +112,7 @@ static int crypto_cbc_encrypt(struct blkcipher_desc *desc, static int crypto_cbc_decrypt_segment(struct blkcipher_desc *desc, struct blkcipher_walk *walk, - struct crypto_cipher *tfm, - void (*xor)(u8 *, const u8 *, - unsigned int)) + struct crypto_cipher *tfm) { void (*fn)(struct crypto_tfm *, u8 *, const u8 *) = crypto_cipher_alg(tfm)->cia_decrypt; @@ -134,7 +124,7 @@ static int crypto_cbc_decrypt_segment(struct blkcipher_desc *desc, do { fn(crypto_cipher_tfm(tfm), dst, src); - xor(dst, iv, bsize); + crypto_xor(dst, iv, bsize); iv = src; src += bsize; @@ -148,9 +138,7 @@ static int crypto_cbc_decrypt_segment(struct blkcipher_desc *desc, static int crypto_cbc_decrypt_inplace(struct blkcipher_desc *desc, struct blkcipher_walk *walk, - struct crypto_cipher *tfm, - void (*xor)(u8 *, const u8 *, - unsigned int)) + struct crypto_cipher *tfm) { void (*fn)(struct crypto_tfm *, u8 *, const u8 *) = crypto_cipher_alg(tfm)->cia_decrypt; @@ -171,11 +159,11 @@ static int crypto_cbc_decrypt_inplace(struct blkcipher_desc *desc, fn(crypto_cipher_tfm(tfm), src, src); if ((nbytes -= bsize) < bsize) break; - xor(src, src - bsize, bsize); + crypto_xor(src, src - bsize, bsize); src -= bsize; } - xor(src, first_iv, bsize); + crypto_xor(src, first_iv, bsize); return nbytes; } @@ -188,7 +176,6 @@ static int crypto_cbc_decrypt(struct blkcipher_desc *desc, struct crypto_blkcipher *tfm = desc->tfm; struct crypto_cbc_ctx *ctx = crypto_blkcipher_ctx(tfm); struct crypto_cipher *child = ctx->child; - void (*xor)(u8 *, const u8 *, unsigned int bs) = ctx->xor; int err; blkcipher_walk_init(&walk, dst, src, nbytes); @@ -196,48 +183,15 @@ static int crypto_cbc_decrypt(struct blkcipher_desc *desc, while ((nbytes = walk.nbytes)) { if (walk.src.virt.addr == walk.dst.virt.addr) - nbytes = crypto_cbc_decrypt_inplace(desc, &walk, child, - xor); + nbytes = crypto_cbc_decrypt_inplace(desc, &walk, child); else - nbytes = crypto_cbc_decrypt_segment(desc, &walk, child, - xor); + nbytes = crypto_cbc_decrypt_segment(desc, &walk, child); err = blkcipher_walk_done(desc, &walk, nbytes); } return err; } -static void xor_byte(u8 *a, const u8 *b, unsigned int bs) -{ - do { - *a++ ^= *b++; - } while (--bs); -} - -static void xor_quad(u8 *dst, const u8 *src, unsigned int bs) -{ - u32 *a = (u32 *)dst; - u32 *b = (u32 *)src; - - do { - *a++ ^= *b++; - } while ((bs -= 4)); -} - -static void xor_64(u8 *a, const u8 *b, unsigned int bs) -{ - ((u32 *)a)[0] ^= ((u32 *)b)[0]; - ((u32 *)a)[1] ^= ((u32 *)b)[1]; -} - -static void xor_128(u8 *a, const u8 *b, unsigned int bs) -{ - ((u32 *)a)[0] ^= ((u32 *)b)[0]; - ((u32 *)a)[1] ^= ((u32 *)b)[1]; - ((u32 *)a)[2] ^= ((u32 *)b)[2]; - ((u32 *)a)[3] ^= ((u32 *)b)[3]; -} - static int crypto_cbc_init_tfm(struct crypto_tfm *tfm) { struct crypto_instance *inst = (void *)tfm->__crt_alg; @@ -245,22 +199,6 @@ static int crypto_cbc_init_tfm(struct crypto_tfm *tfm) struct crypto_cbc_ctx *ctx = crypto_tfm_ctx(tfm); struct crypto_cipher *cipher; - switch (crypto_tfm_alg_blocksize(tfm)) { - case 8: - ctx->xor = xor_64; - break; - - case 16: - ctx->xor = xor_128; - break; - - default: - if (crypto_tfm_alg_blocksize(tfm) % 4) - ctx->xor = xor_byte; - else - ctx->xor = xor_quad; - } - cipher = crypto_spawn_cipher(spawn); if (IS_ERR(cipher)) return PTR_ERR(cipher); @@ -300,8 +238,9 @@ static struct crypto_instance *crypto_cbc_alloc(struct rtattr **tb) inst->alg.cra_alignmask = alg->cra_alignmask; inst->alg.cra_type = &crypto_blkcipher_type; - if (!(alg->cra_blocksize % 4)) - inst->alg.cra_alignmask |= 3; + /* We access the data as u32s when xoring. */ + inst->alg.cra_alignmask |= __alignof__(u32) - 1; + inst->alg.cra_blkcipher.ivsize = alg->cra_blocksize; inst->alg.cra_blkcipher.min_keysize = alg->cra_cipher.cia_min_keysize; inst->alg.cra_blkcipher.max_keysize = alg->cra_cipher.cia_max_keysize;