From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D09D8C64E90 for ; Tue, 17 Nov 2020 13:50:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 71B1F24199 for ; Tue, 17 Nov 2020 13:50:51 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="cet0n5Jf" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732324AbgKQNu3 (ORCPT ); Tue, 17 Nov 2020 08:50:29 -0500 Received: from mail.kernel.org ([198.145.29.99]:42358 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732319AbgKQNch (ORCPT ); Tue, 17 Nov 2020 08:32:37 -0500 Received: from e123331-lin.nice.arm.com (lfbn-nic-1-188-42.w2-15.abo.wanadoo.fr [2.15.37.42]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 8B5ED2463D; Tue, 17 Nov 2020 13:32:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1605619958; bh=Iyf4Rgv1+x9PtEcqoWVcwfYPM8emMHSynQZDAw8Vlh8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=cet0n5JfTryI2r5wS0lajmlBaXW1o1RRiB4pZeSqFUJRK0Wwka+h0yt1RlMiiiUbm VXdHZ6gmvmY4vFt072CdGV3xX1YatYMgxHBI6/vxVm/7DPdVepaOZ8fjkdrp92Tnmb wZ7aKg3DlscXPu8H+jZ5tdfyq2Ctp+NBCqcyRzzk= From: Ard Biesheuvel To: linux-crypto@vger.kernel.org Cc: herbert@gondor.apana.org.au, linux-arm-kernel@lists.infradead.org, Ard Biesheuvel , Ondrej Mosnacek , Eric Biggers Subject: [PATCH v3 1/4] crypto: aegis128 - wipe plaintext and tag if decryption fails Date: Tue, 17 Nov 2020 14:32:11 +0100 Message-Id: <20201117133214.29114-2-ardb@kernel.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20201117133214.29114-1-ardb@kernel.org> References: <20201117133214.29114-1-ardb@kernel.org> Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org The AEGIS spec mentions explicitly that the security guarantees hold only if the resulting plaintext and tag of a failed decryption are withheld. So ensure that we abide by this. While at it, drop the unused struct aead_request *req parameter from crypto_aegis128_process_crypt(). Reviewed-by: Ondrej Mosnacek Signed-off-by: Ard Biesheuvel --- crypto/aegis128-core.c | 32 ++++++++++++++++---- 1 file changed, 26 insertions(+), 6 deletions(-) diff --git a/crypto/aegis128-core.c b/crypto/aegis128-core.c index 44fb4956f0dd..3a71235892f5 100644 --- a/crypto/aegis128-core.c +++ b/crypto/aegis128-core.c @@ -154,6 +154,12 @@ static void crypto_aegis128_ad(struct aegis_state *state, } } +static void crypto_aegis128_wipe_chunk(struct aegis_state *state, u8 *dst, + const u8 *src, unsigned int size) +{ + memzero_explicit(dst, size); +} + static void crypto_aegis128_encrypt_chunk(struct aegis_state *state, u8 *dst, const u8 *src, unsigned int size) { @@ -324,7 +330,6 @@ static void crypto_aegis128_process_ad(struct aegis_state *state, static __always_inline int crypto_aegis128_process_crypt(struct aegis_state *state, - struct aead_request *req, struct skcipher_walk *walk, void (*crypt)(struct aegis_state *state, u8 *dst, const u8 *src, @@ -403,14 +408,14 @@ static int crypto_aegis128_encrypt(struct aead_request *req) if (aegis128_do_simd()) { crypto_aegis128_init_simd(&state, &ctx->key, req->iv); crypto_aegis128_process_ad(&state, req->src, req->assoclen); - crypto_aegis128_process_crypt(&state, req, &walk, + crypto_aegis128_process_crypt(&state, &walk, crypto_aegis128_encrypt_chunk_simd); crypto_aegis128_final_simd(&state, &tag, req->assoclen, cryptlen); } else { crypto_aegis128_init(&state, &ctx->key, req->iv); crypto_aegis128_process_ad(&state, req->src, req->assoclen); - crypto_aegis128_process_crypt(&state, req, &walk, + crypto_aegis128_process_crypt(&state, &walk, crypto_aegis128_encrypt_chunk); crypto_aegis128_final(&state, &tag, req->assoclen, cryptlen); } @@ -438,19 +443,34 @@ static int crypto_aegis128_decrypt(struct aead_request *req) if (aegis128_do_simd()) { crypto_aegis128_init_simd(&state, &ctx->key, req->iv); crypto_aegis128_process_ad(&state, req->src, req->assoclen); - crypto_aegis128_process_crypt(&state, req, &walk, + crypto_aegis128_process_crypt(&state, &walk, crypto_aegis128_decrypt_chunk_simd); crypto_aegis128_final_simd(&state, &tag, req->assoclen, cryptlen); } else { crypto_aegis128_init(&state, &ctx->key, req->iv); crypto_aegis128_process_ad(&state, req->src, req->assoclen); - crypto_aegis128_process_crypt(&state, req, &walk, + crypto_aegis128_process_crypt(&state, &walk, crypto_aegis128_decrypt_chunk); crypto_aegis128_final(&state, &tag, req->assoclen, cryptlen); } - return crypto_memneq(tag.bytes, zeros, authsize) ? -EBADMSG : 0; + if (unlikely(crypto_memneq(tag.bytes, zeros, authsize))) { + /* + * From Chapter 4. 'Security Analysis' of the AEGIS spec [0] + * + * "3. If verification fails, the decrypted plaintext and the + * wrong authentication tag should not be given as output." + * + * [0] https://competitions.cr.yp.to/round3/aegisv11.pdf + */ + skcipher_walk_aead_decrypt(&walk, req, false); + crypto_aegis128_process_crypt(NULL, &walk, + crypto_aegis128_wipe_chunk); + memzero_explicit(&tag, sizeof(tag)); + return -EBADMSG; + } + return 0; } static struct aead_alg crypto_aegis128_alg = { -- 2.17.1 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7533EC2D0E4 for ; Tue, 17 Nov 2020 13:34:08 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 03F8021534 for ; Tue, 17 Nov 2020 13:34:07 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="iHK5R2y4"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="cet0n5Jf" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 03F8021534 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:MIME-Version:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:References:In-Reply-To:Message-Id:Date:Subject:To: From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=Jb+YngOH+niHOrL9EL0V2NXtIpS/mBtx6ybY9szDkpA=; b=iHK5R2y4F8p0Du6GHkTCfLaFlH 5keCtibqWRG700OgWKq1g89hwPU3MXUarxloHZYDVg8WCMPe8voHI9YCrvC3NSiQZVBss/Zvp47FB Y4+imHHKnsQo/KDqDE6KtpJr9YCp25t75OKezD8CQdRF6pmK8l1oITE2AfFj3QYtJ0ejGG4OpddCJ h/FuMefMF1vnKkLSO4Py+8PZg2fSqGC/KsVNqiwjm/K+K+34NGRdwoOeq8Po/e4UdwCCV/W7dyvPd 1GkcyhROs8OBf1VhBUjP8m0dLwOITzxPOF2JT+v12wAr8ZjHlXZKgZOgfc2m48OrSioWViXPQwMUV Eyy99WjA==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kf16D-0003j4-PO; Tue, 17 Nov 2020 13:32:45 +0000 Received: from mail.kernel.org ([198.145.29.99]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1kf166-0003hI-Qp for linux-arm-kernel@lists.infradead.org; Tue, 17 Nov 2020 13:32:39 +0000 Received: from e123331-lin.nice.arm.com (lfbn-nic-1-188-42.w2-15.abo.wanadoo.fr [2.15.37.42]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 8B5ED2463D; Tue, 17 Nov 2020 13:32:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1605619958; bh=Iyf4Rgv1+x9PtEcqoWVcwfYPM8emMHSynQZDAw8Vlh8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=cet0n5JfTryI2r5wS0lajmlBaXW1o1RRiB4pZeSqFUJRK0Wwka+h0yt1RlMiiiUbm VXdHZ6gmvmY4vFt072CdGV3xX1YatYMgxHBI6/vxVm/7DPdVepaOZ8fjkdrp92Tnmb wZ7aKg3DlscXPu8H+jZ5tdfyq2Ctp+NBCqcyRzzk= From: Ard Biesheuvel To: linux-crypto@vger.kernel.org Subject: [PATCH v3 1/4] crypto: aegis128 - wipe plaintext and tag if decryption fails Date: Tue, 17 Nov 2020 14:32:11 +0100 Message-Id: <20201117133214.29114-2-ardb@kernel.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20201117133214.29114-1-ardb@kernel.org> References: <20201117133214.29114-1-ardb@kernel.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201117_083239_021288_ABE5F93F X-CRM114-Status: GOOD ( 15.73 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Eric Biggers , Ondrej Mosnacek , herbert@gondor.apana.org.au, linux-arm-kernel@lists.infradead.org, Ard Biesheuvel MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org The AEGIS spec mentions explicitly that the security guarantees hold only if the resulting plaintext and tag of a failed decryption are withheld. So ensure that we abide by this. While at it, drop the unused struct aead_request *req parameter from crypto_aegis128_process_crypt(). Reviewed-by: Ondrej Mosnacek Signed-off-by: Ard Biesheuvel --- crypto/aegis128-core.c | 32 ++++++++++++++++---- 1 file changed, 26 insertions(+), 6 deletions(-) diff --git a/crypto/aegis128-core.c b/crypto/aegis128-core.c index 44fb4956f0dd..3a71235892f5 100644 --- a/crypto/aegis128-core.c +++ b/crypto/aegis128-core.c @@ -154,6 +154,12 @@ static void crypto_aegis128_ad(struct aegis_state *state, } } +static void crypto_aegis128_wipe_chunk(struct aegis_state *state, u8 *dst, + const u8 *src, unsigned int size) +{ + memzero_explicit(dst, size); +} + static void crypto_aegis128_encrypt_chunk(struct aegis_state *state, u8 *dst, const u8 *src, unsigned int size) { @@ -324,7 +330,6 @@ static void crypto_aegis128_process_ad(struct aegis_state *state, static __always_inline int crypto_aegis128_process_crypt(struct aegis_state *state, - struct aead_request *req, struct skcipher_walk *walk, void (*crypt)(struct aegis_state *state, u8 *dst, const u8 *src, @@ -403,14 +408,14 @@ static int crypto_aegis128_encrypt(struct aead_request *req) if (aegis128_do_simd()) { crypto_aegis128_init_simd(&state, &ctx->key, req->iv); crypto_aegis128_process_ad(&state, req->src, req->assoclen); - crypto_aegis128_process_crypt(&state, req, &walk, + crypto_aegis128_process_crypt(&state, &walk, crypto_aegis128_encrypt_chunk_simd); crypto_aegis128_final_simd(&state, &tag, req->assoclen, cryptlen); } else { crypto_aegis128_init(&state, &ctx->key, req->iv); crypto_aegis128_process_ad(&state, req->src, req->assoclen); - crypto_aegis128_process_crypt(&state, req, &walk, + crypto_aegis128_process_crypt(&state, &walk, crypto_aegis128_encrypt_chunk); crypto_aegis128_final(&state, &tag, req->assoclen, cryptlen); } @@ -438,19 +443,34 @@ static int crypto_aegis128_decrypt(struct aead_request *req) if (aegis128_do_simd()) { crypto_aegis128_init_simd(&state, &ctx->key, req->iv); crypto_aegis128_process_ad(&state, req->src, req->assoclen); - crypto_aegis128_process_crypt(&state, req, &walk, + crypto_aegis128_process_crypt(&state, &walk, crypto_aegis128_decrypt_chunk_simd); crypto_aegis128_final_simd(&state, &tag, req->assoclen, cryptlen); } else { crypto_aegis128_init(&state, &ctx->key, req->iv); crypto_aegis128_process_ad(&state, req->src, req->assoclen); - crypto_aegis128_process_crypt(&state, req, &walk, + crypto_aegis128_process_crypt(&state, &walk, crypto_aegis128_decrypt_chunk); crypto_aegis128_final(&state, &tag, req->assoclen, cryptlen); } - return crypto_memneq(tag.bytes, zeros, authsize) ? -EBADMSG : 0; + if (unlikely(crypto_memneq(tag.bytes, zeros, authsize))) { + /* + * From Chapter 4. 'Security Analysis' of the AEGIS spec [0] + * + * "3. If verification fails, the decrypted plaintext and the + * wrong authentication tag should not be given as output." + * + * [0] https://competitions.cr.yp.to/round3/aegisv11.pdf + */ + skcipher_walk_aead_decrypt(&walk, req, false); + crypto_aegis128_process_crypt(NULL, &walk, + crypto_aegis128_wipe_chunk); + memzero_explicit(&tag, sizeof(tag)); + return -EBADMSG; + } + return 0; } static struct aead_alg crypto_aegis128_alg = { -- 2.17.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel