From: Steffen Klassert Subject: [PATCH 2/2] crypto: authenc - move saved IV in front of the ablkcipher request Date: Tue, 23 Feb 2010 07:22:37 +0100 Message-ID: <20100223062237.GE29013@secunet.com> References: <20100223062109.GD29013@secunet.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-crypto@vger.kernel.org To: Herbert Xu Return-path: Received: from a.mx.secunet.com ([213.68.205.161]:55057 "EHLO a.mx.secunet.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751254Ab0BWGZZ (ORCPT ); Tue, 23 Feb 2010 01:25:25 -0500 Content-Disposition: inline In-Reply-To: <20100223062109.GD29013@secunet.com> Sender: linux-crypto-owner@vger.kernel.org List-ID: In crypto_authenc_encrypt() we save the IV behind the ablkcipher request. To save space on the request, we overwrite the ablkcipher request with a ahash request after encryption. So the IV may be overwritten by the ahash request. This patch fixes this by placing the IV in front of the ablkcipher/ahash request. Signed-off-by: Steffen Klassert --- crypto/authenc.c | 25 ++++++++++++++----------- 1 files changed, 14 insertions(+), 11 deletions(-) diff --git a/crypto/authenc.c b/crypto/authenc.c index 6287cfd..2bb7348 100644 --- a/crypto/authenc.c +++ b/crypto/authenc.c @@ -386,11 +386,13 @@ static int crypto_authenc_encrypt(struct aead_request *req) { struct crypto_aead *authenc = crypto_aead_reqtfm(req); struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc); - struct ablkcipher_request *abreq = aead_request_ctx(req); + struct authenc_request_ctx *areq_ctx = aead_request_ctx(req); struct crypto_ablkcipher *enc = ctx->enc; struct scatterlist *dst = req->dst; unsigned int cryptlen = req->cryptlen; - u8 *iv = (u8 *)(abreq + 1) + crypto_ablkcipher_reqsize(enc); + struct ablkcipher_request *abreq = (void *)(areq_ctx->tail + + ctx->reqoff); + u8 *iv = (u8 *)abreq - crypto_ablkcipher_ivsize(enc); int err; ablkcipher_request_set_tfm(abreq, enc); @@ -546,10 +548,6 @@ static int crypto_authenc_init_tfm(struct crypto_tfm *tfm) if (IS_ERR(auth)) return PTR_ERR(auth); - ctx->reqoff = ALIGN(2 * crypto_ahash_digestsize(auth) + - crypto_ahash_alignmask(auth), - crypto_ahash_alignmask(auth) + 1); - enc = crypto_spawn_skcipher(&ictx->enc); err = PTR_ERR(enc); if (IS_ERR(enc)) @@ -558,13 +556,18 @@ static int crypto_authenc_init_tfm(struct crypto_tfm *tfm) ctx->auth = auth; ctx->enc = enc; - tfm->crt_aead.reqsize = max_t(unsigned int, - crypto_ahash_reqsize(auth) + ctx->reqoff + - sizeof(struct authenc_request_ctx) + + ctx->reqoff = ALIGN(2 * crypto_ahash_digestsize(auth) + + crypto_ahash_alignmask(auth), + crypto_ahash_alignmask(auth) + 1) + + crypto_ablkcipher_ivsize(enc); + + tfm->crt_aead.reqsize = sizeof(struct authenc_request_ctx) + + ctx->reqoff + + max_t(unsigned int, + crypto_ahash_reqsize(auth) + sizeof(struct ahash_request), sizeof(struct skcipher_givcrypt_request) + - crypto_ablkcipher_reqsize(enc) + - crypto_ablkcipher_ivsize(enc)); + crypto_ablkcipher_reqsize(enc)); return 0; -- 1.5.6.5