From patchwork Tue Oct 18 07:10:02 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "tianjia.zhang" X-Patchwork-Id: 616141 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CC5BBC4332F for ; Tue, 18 Oct 2022 07:11:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230390AbiJRHLy (ORCPT ); Tue, 18 Oct 2022 03:11:54 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37312 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230120AbiJRHLG (ORCPT ); Tue, 18 Oct 2022 03:11:06 -0400 Received: from out30-45.freemail.mail.aliyun.com (out30-45.freemail.mail.aliyun.com [115.124.30.45]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 98548A98F9; Tue, 18 Oct 2022 00:10:42 -0700 (PDT) X-Alimail-AntiSpam: AC=PASS; BC=-1|-1; BR=01201311R171e4; CH=green; DM=||false|; DS=||; FP=0|-1|-1|-1|0|-1|-1|-1; HT=ay29a033018046050; MF=tianjia.zhang@linux.alibaba.com; NM=1; PH=DS; RN=15; SR=0; TI=SMTPD_---0VSTUHcm_1666077032; Received: from localhost(mailfrom:tianjia.zhang@linux.alibaba.com fp:SMTPD_---0VSTUHcm_1666077032) by smtp.aliyun-inc.com; Tue, 18 Oct 2022 15:10:34 +0800 From: Tianjia Zhang To: Herbert Xu , "David S. Miller" , Jussi Kivilinna , Ard Biesheuvel , Mark Brown , Catalin Marinas , Will Deacon , Maxime Coquelin , Alexandre Torgue , Eric Biggers , linux-crypto@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com Cc: Tianjia Zhang Subject: [PATCH v2 11/15] crypto: essiv - allow digestsize to be greater than keysize Date: Tue, 18 Oct 2022 15:10:02 +0800 Message-Id: <20221018071006.5717-12-tianjia.zhang@linux.alibaba.com> X-Mailer: git-send-email 2.24.3 (Apple Git-128) In-Reply-To: <20221018071006.5717-1-tianjia.zhang@linux.alibaba.com> References: <20221018071006.5717-1-tianjia.zhang@linux.alibaba.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org In essiv mode, the digest of the hash algorithm is used as the key to encrypt the IV. The current implementation requires that the digest size of the hash algorithm is equal to the key size, which will exclude algorithms that do not meet this situation, such as essiv(cbc(sm4),sm3), the hash result of sm3 is fixed 256 bits, and the key size of sm4 symmetric algorithm is fixed 128 bits, which makes it impossible to use essiv mode. This patch allows algorithms whose digest size is greater than key size to use esssiv mode by truncating the digest. Signed-off-by: Tianjia Zhang --- crypto/essiv.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/crypto/essiv.c b/crypto/essiv.c index e33369df9034..6ee5a61bcae4 100644 --- a/crypto/essiv.c +++ b/crypto/essiv.c @@ -68,6 +68,7 @@ static int essiv_skcipher_setkey(struct crypto_skcipher *tfm, { struct essiv_tfm_ctx *tctx = crypto_skcipher_ctx(tfm); u8 salt[HASH_MAX_DIGESTSIZE]; + unsigned int saltlen; int err; crypto_skcipher_clear_flags(tctx->u.skcipher, CRYPTO_TFM_REQ_MASK); @@ -86,8 +87,11 @@ static int essiv_skcipher_setkey(struct crypto_skcipher *tfm, crypto_cipher_set_flags(tctx->essiv_cipher, crypto_skcipher_get_flags(tfm) & CRYPTO_TFM_REQ_MASK); - return crypto_cipher_setkey(tctx->essiv_cipher, salt, - crypto_shash_digestsize(tctx->hash)); + + saltlen = min(crypto_shash_digestsize(tctx->hash), + crypto_skcipher_max_keysize(tctx->u.skcipher)); + + return crypto_cipher_setkey(tctx->essiv_cipher, salt, saltlen); } static int essiv_aead_setkey(struct crypto_aead *tfm, const u8 *key, @@ -418,8 +422,7 @@ static bool essiv_supported_algorithms(const char *essiv_cipher_name, if (IS_ERR(alg)) return false; - if (hash_alg->digestsize < alg->cra_cipher.cia_min_keysize || - hash_alg->digestsize > alg->cra_cipher.cia_max_keysize) + if (hash_alg->digestsize < alg->cra_cipher.cia_min_keysize) goto out; if (ivsize != alg->cra_blocksize)