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=-10.0 required=3.0 tests=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=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 0B51DC433E1 for ; Thu, 25 Jun 2020 12:44:37 +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 6F3FF206BE for ; Thu, 25 Jun 2020 12:44:36 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="fpxgTAej"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="fSa0m+ge" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6F3FF206BE 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-amlogic-bounces+linux-amlogic=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:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version: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=tDacVEroQNuSEc3Kqy0/nQeG2dAuHuhhY76+q7eSj5Q=; b=fpxgTAej+1s5xfantU3p6JQFW aJClbc6Sll47pnXq6kaPXaL+BtYeogAO/6F11syw+ue74bvOCAR47h4JNb3YpoWcau4WmRuIrtYJD px0dsGZlNFCqtmu0JfyTMpUB2f3Ptt7KaUIi1cd/zwvnzJgdgHcrDowN9RCr8o8f/CWZ2ECk/J5uD ADT2xVlXNd3LwHG09TdMqYZNpm+uVjBQ/4C2KXdlE+scDvi+OSGdidMU5RwwqOk7j4aytaMg97USt 49Z12Vc7LoJ3InuPZCOuC16RszuvGqMpmHvBc9Bg2ZwEDs+tTHZUk65mVhH9W2d3Ls1+aNFORSO+d w9mS8l2Fw==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1joREw-0005ma-10; Thu, 25 Jun 2020 12:44:26 +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 1joRES-0005Wk-6o; Thu, 25 Jun 2020 12:43:57 +0000 Received: from localhost.localdomain (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 E006C20724; Thu, 25 Jun 2020 12:43:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1593089035; bh=mJ44RN1Ax7UO5kUEhNQNsOxr9UMAVZrtpGUzPdPjV5w=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=fSa0m+genEQoHZRSnzLuXGzBji6ZPg9bb3YkrnePsj99vW84ULC56q+FgTopfKnI8 vQAU4erv7QryNTjNwiCdGr6HsqA4hb7br2jW+tamvgaWVDhQeQDZ/UHGDBZ4QBy9jq vK+kAK/fLUw4f7Bwx6LRgAXL8G9mU5wNMktVPh3s= From: Ard Biesheuvel To: linux-crypto@vger.kernel.org Subject: [PATCH 09/12] crypto: mxs-dcp - permit asynchronous skcipher as fallback Date: Thu, 25 Jun 2020 14:42:50 +0200 Message-Id: <20200625124253.1906557-10-ardb@kernel.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200625124253.1906557-1-ardb@kernel.org> References: <20200625124253.1906557-1-ardb@kernel.org> MIME-Version: 1.0 X-BeenThere: linux-amlogic@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 , Tom Lendacky , Jamie Iles , Herbert Xu , Rohit Maheshwari , Fabio Estevam , Sascha Hauer , Vinay Kumar Yadav , Maxime Ripard , "David S. Miller" , Chen-Yu Tsai , Corentin Labbe , NXP Linux Team , Pengutronix Kernel Team , Ayush Sawal , linux-amlogic@lists.infradead.org, linux-omap@vger.kernel.org, Shawn Guo , Ard Biesheuvel , linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-amlogic" Errors-To: linux-amlogic-bounces+linux-amlogic=archiver.kernel.org@lists.infradead.org Even though the mxs-dcp driver implements asynchronous versions of ecb(aes) and cbc(aes), the fallbacks it allocates are required to be synchronous. Given that SIMD based software implementations are usually asynchronous as well, even though they rarely complete asynchronously (this typically only happens in cases where the request was made from softirq context, while SIMD was already in use in the task context that it interrupted), these implementations are disregarded, and either the generic C version or another table based version implemented in assembler is selected instead. Since falling back to synchronous AES is not only a performance issue, but potentially a security issue as well (due to the fact that table based AES is not time invariant), let's fix this, by allocating an ordinary skcipher as the fallback, and invoke it with the completion routine that was given to the outer request. Signed-off-by: Ard Biesheuvel --- drivers/crypto/mxs-dcp.c | 33 ++++++++++---------- 1 file changed, 17 insertions(+), 16 deletions(-) diff --git a/drivers/crypto/mxs-dcp.c b/drivers/crypto/mxs-dcp.c index d84530293036..909a7eb748e3 100644 --- a/drivers/crypto/mxs-dcp.c +++ b/drivers/crypto/mxs-dcp.c @@ -97,7 +97,7 @@ struct dcp_async_ctx { unsigned int hot:1; /* Crypto-specific context */ - struct crypto_sync_skcipher *fallback; + struct crypto_skcipher *fallback; unsigned int key_len; uint8_t key[AES_KEYSIZE_128]; }; @@ -105,6 +105,7 @@ struct dcp_async_ctx { struct dcp_aes_req_ctx { unsigned int enc:1; unsigned int ecb:1; + struct skcipher_request fallback_req; // keep at the end }; struct dcp_sha_req_ctx { @@ -426,21 +427,20 @@ static int dcp_chan_thread_aes(void *data) static int mxs_dcp_block_fallback(struct skcipher_request *req, int enc) { struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); + struct dcp_aes_req_ctx *rctx = skcipher_request_ctx(req); struct dcp_async_ctx *ctx = crypto_skcipher_ctx(tfm); - SYNC_SKCIPHER_REQUEST_ON_STACK(subreq, ctx->fallback); int ret; - skcipher_request_set_sync_tfm(subreq, ctx->fallback); - skcipher_request_set_callback(subreq, req->base.flags, NULL, NULL); - skcipher_request_set_crypt(subreq, req->src, req->dst, + skcipher_request_set_tfm(&rctx->fallback_req, ctx->fallback); + skcipher_request_set_callback(&rctx->fallback_req, req->base.flags, + req->base.complete, req->base.data); + skcipher_request_set_crypt(&rctx->fallback_req, req->src, req->dst, req->cryptlen, req->iv); if (enc) - ret = crypto_skcipher_encrypt(subreq); + ret = crypto_skcipher_encrypt(&rctx->fallback_req); else - ret = crypto_skcipher_decrypt(subreq); - - skcipher_request_zero(subreq); + ret = crypto_skcipher_decrypt(&rctx->fallback_req); return ret; } @@ -510,24 +510,25 @@ static int mxs_dcp_aes_setkey(struct crypto_skcipher *tfm, const u8 *key, * but is supported by in-kernel software implementation, we use * software fallback. */ - crypto_sync_skcipher_clear_flags(actx->fallback, CRYPTO_TFM_REQ_MASK); - crypto_sync_skcipher_set_flags(actx->fallback, + crypto_skcipher_clear_flags(actx->fallback, CRYPTO_TFM_REQ_MASK); + crypto_skcipher_set_flags(actx->fallback, tfm->base.crt_flags & CRYPTO_TFM_REQ_MASK); - return crypto_sync_skcipher_setkey(actx->fallback, key, len); + return crypto_skcipher_setkey(actx->fallback, key, len); } static int mxs_dcp_aes_fallback_init_tfm(struct crypto_skcipher *tfm) { const char *name = crypto_tfm_alg_name(crypto_skcipher_tfm(tfm)); struct dcp_async_ctx *actx = crypto_skcipher_ctx(tfm); - struct crypto_sync_skcipher *blk; + struct crypto_skcipher *blk; - blk = crypto_alloc_sync_skcipher(name, 0, CRYPTO_ALG_NEED_FALLBACK); + blk = crypto_alloc_skcipher(name, 0, CRYPTO_ALG_NEED_FALLBACK); if (IS_ERR(blk)) return PTR_ERR(blk); actx->fallback = blk; - crypto_skcipher_set_reqsize(tfm, sizeof(struct dcp_aes_req_ctx)); + crypto_skcipher_set_reqsize(tfm, sizeof(struct dcp_aes_req_ctx) + + crypto_skcipher_reqsize(blk)); return 0; } @@ -535,7 +536,7 @@ static void mxs_dcp_aes_fallback_exit_tfm(struct crypto_skcipher *tfm) { struct dcp_async_ctx *actx = crypto_skcipher_ctx(tfm); - crypto_free_sync_skcipher(actx->fallback); + crypto_free_skcipher(actx->fallback); } /* -- 2.27.0 _______________________________________________ linux-amlogic mailing list linux-amlogic@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-amlogic 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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,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 52DBEC433E1 for ; Thu, 25 Jun 2020 12:43:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 30D9F208C7 for ; Thu, 25 Jun 2020 12:43:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1593089037; bh=mJ44RN1Ax7UO5kUEhNQNsOxr9UMAVZrtpGUzPdPjV5w=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=tYtWMcrIbLTLTDYMZ2xZJD+s1XX5NvKfCTgCB1OD6a+w0mslxJnDenn9bE/MMxZMH 1CLPVNuiY0gU6XaldKh6R28xA2XEjn4CEFkt81Y2eLQ2jL189gOpfQXW0Ak4Z8p/nk fIszgU6mg2x0WwGuBVS8bgOWlHWL2t+/kpK47M7U= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2404710AbgFYMn4 (ORCPT ); Thu, 25 Jun 2020 08:43:56 -0400 Received: from mail.kernel.org ([198.145.29.99]:46280 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2404285AbgFYMn4 (ORCPT ); Thu, 25 Jun 2020 08:43:56 -0400 Received: from localhost.localdomain (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 E006C20724; Thu, 25 Jun 2020 12:43:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1593089035; bh=mJ44RN1Ax7UO5kUEhNQNsOxr9UMAVZrtpGUzPdPjV5w=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=fSa0m+genEQoHZRSnzLuXGzBji6ZPg9bb3YkrnePsj99vW84ULC56q+FgTopfKnI8 vQAU4erv7QryNTjNwiCdGr6HsqA4hb7br2jW+tamvgaWVDhQeQDZ/UHGDBZ4QBy9jq vK+kAK/fLUw4f7Bwx6LRgAXL8G9mU5wNMktVPh3s= From: Ard Biesheuvel To: linux-crypto@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org, linux-omap@vger.kernel.org, linux-amlogic@lists.infradead.org, Ard Biesheuvel , Corentin Labbe , Herbert Xu , "David S. Miller" , Maxime Ripard , Chen-Yu Tsai , Tom Lendacky , Ayush Sawal , Vinay Kumar Yadav , Rohit Maheshwari , Shawn Guo , Sascha Hauer , Pengutronix Kernel Team , Fabio Estevam , NXP Linux Team , Jamie Iles , Eric Biggers Subject: [PATCH 09/12] crypto: mxs-dcp - permit asynchronous skcipher as fallback Date: Thu, 25 Jun 2020 14:42:50 +0200 Message-Id: <20200625124253.1906557-10-ardb@kernel.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200625124253.1906557-1-ardb@kernel.org> References: <20200625124253.1906557-1-ardb@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-crypto-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org Even though the mxs-dcp driver implements asynchronous versions of ecb(aes) and cbc(aes), the fallbacks it allocates are required to be synchronous. Given that SIMD based software implementations are usually asynchronous as well, even though they rarely complete asynchronously (this typically only happens in cases where the request was made from softirq context, while SIMD was already in use in the task context that it interrupted), these implementations are disregarded, and either the generic C version or another table based version implemented in assembler is selected instead. Since falling back to synchronous AES is not only a performance issue, but potentially a security issue as well (due to the fact that table based AES is not time invariant), let's fix this, by allocating an ordinary skcipher as the fallback, and invoke it with the completion routine that was given to the outer request. Signed-off-by: Ard Biesheuvel --- drivers/crypto/mxs-dcp.c | 33 ++++++++++---------- 1 file changed, 17 insertions(+), 16 deletions(-) diff --git a/drivers/crypto/mxs-dcp.c b/drivers/crypto/mxs-dcp.c index d84530293036..909a7eb748e3 100644 --- a/drivers/crypto/mxs-dcp.c +++ b/drivers/crypto/mxs-dcp.c @@ -97,7 +97,7 @@ struct dcp_async_ctx { unsigned int hot:1; /* Crypto-specific context */ - struct crypto_sync_skcipher *fallback; + struct crypto_skcipher *fallback; unsigned int key_len; uint8_t key[AES_KEYSIZE_128]; }; @@ -105,6 +105,7 @@ struct dcp_async_ctx { struct dcp_aes_req_ctx { unsigned int enc:1; unsigned int ecb:1; + struct skcipher_request fallback_req; // keep at the end }; struct dcp_sha_req_ctx { @@ -426,21 +427,20 @@ static int dcp_chan_thread_aes(void *data) static int mxs_dcp_block_fallback(struct skcipher_request *req, int enc) { struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); + struct dcp_aes_req_ctx *rctx = skcipher_request_ctx(req); struct dcp_async_ctx *ctx = crypto_skcipher_ctx(tfm); - SYNC_SKCIPHER_REQUEST_ON_STACK(subreq, ctx->fallback); int ret; - skcipher_request_set_sync_tfm(subreq, ctx->fallback); - skcipher_request_set_callback(subreq, req->base.flags, NULL, NULL); - skcipher_request_set_crypt(subreq, req->src, req->dst, + skcipher_request_set_tfm(&rctx->fallback_req, ctx->fallback); + skcipher_request_set_callback(&rctx->fallback_req, req->base.flags, + req->base.complete, req->base.data); + skcipher_request_set_crypt(&rctx->fallback_req, req->src, req->dst, req->cryptlen, req->iv); if (enc) - ret = crypto_skcipher_encrypt(subreq); + ret = crypto_skcipher_encrypt(&rctx->fallback_req); else - ret = crypto_skcipher_decrypt(subreq); - - skcipher_request_zero(subreq); + ret = crypto_skcipher_decrypt(&rctx->fallback_req); return ret; } @@ -510,24 +510,25 @@ static int mxs_dcp_aes_setkey(struct crypto_skcipher *tfm, const u8 *key, * but is supported by in-kernel software implementation, we use * software fallback. */ - crypto_sync_skcipher_clear_flags(actx->fallback, CRYPTO_TFM_REQ_MASK); - crypto_sync_skcipher_set_flags(actx->fallback, + crypto_skcipher_clear_flags(actx->fallback, CRYPTO_TFM_REQ_MASK); + crypto_skcipher_set_flags(actx->fallback, tfm->base.crt_flags & CRYPTO_TFM_REQ_MASK); - return crypto_sync_skcipher_setkey(actx->fallback, key, len); + return crypto_skcipher_setkey(actx->fallback, key, len); } static int mxs_dcp_aes_fallback_init_tfm(struct crypto_skcipher *tfm) { const char *name = crypto_tfm_alg_name(crypto_skcipher_tfm(tfm)); struct dcp_async_ctx *actx = crypto_skcipher_ctx(tfm); - struct crypto_sync_skcipher *blk; + struct crypto_skcipher *blk; - blk = crypto_alloc_sync_skcipher(name, 0, CRYPTO_ALG_NEED_FALLBACK); + blk = crypto_alloc_skcipher(name, 0, CRYPTO_ALG_NEED_FALLBACK); if (IS_ERR(blk)) return PTR_ERR(blk); actx->fallback = blk; - crypto_skcipher_set_reqsize(tfm, sizeof(struct dcp_aes_req_ctx)); + crypto_skcipher_set_reqsize(tfm, sizeof(struct dcp_aes_req_ctx) + + crypto_skcipher_reqsize(blk)); return 0; } @@ -535,7 +536,7 @@ static void mxs_dcp_aes_fallback_exit_tfm(struct crypto_skcipher *tfm) { struct dcp_async_ctx *actx = crypto_skcipher_ctx(tfm); - crypto_free_sync_skcipher(actx->fallback); + crypto_free_skcipher(actx->fallback); } /* -- 2.27.0 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=-10.0 required=3.0 tests=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=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 D8519C433E0 for ; Thu, 25 Jun 2020 12:46:40 +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 A5DC1206BE for ; Thu, 25 Jun 2020 12:46:40 +0000 (UTC) Authentication-Results: mail.kernel.org; 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a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1593089035; bh=mJ44RN1Ax7UO5kUEhNQNsOxr9UMAVZrtpGUzPdPjV5w=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=fSa0m+genEQoHZRSnzLuXGzBji6ZPg9bb3YkrnePsj99vW84ULC56q+FgTopfKnI8 vQAU4erv7QryNTjNwiCdGr6HsqA4hb7br2jW+tamvgaWVDhQeQDZ/UHGDBZ4QBy9jq vK+kAK/fLUw4f7Bwx6LRgAXL8G9mU5wNMktVPh3s= From: Ard Biesheuvel To: linux-crypto@vger.kernel.org Subject: [PATCH 09/12] crypto: mxs-dcp - permit asynchronous skcipher as fallback Date: Thu, 25 Jun 2020 14:42:50 +0200 Message-Id: <20200625124253.1906557-10-ardb@kernel.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200625124253.1906557-1-ardb@kernel.org> References: <20200625124253.1906557-1-ardb@kernel.org> MIME-Version: 1.0 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 , Tom Lendacky , Jamie Iles , Herbert Xu , Rohit Maheshwari , Fabio Estevam , Sascha Hauer , Vinay Kumar Yadav , Maxime Ripard , "David S. Miller" , Chen-Yu Tsai , Corentin Labbe , NXP Linux Team , Pengutronix Kernel Team , Ayush Sawal , linux-amlogic@lists.infradead.org, linux-omap@vger.kernel.org, Shawn Guo , Ard Biesheuvel , linux-arm-kernel@lists.infradead.org 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 Even though the mxs-dcp driver implements asynchronous versions of ecb(aes) and cbc(aes), the fallbacks it allocates are required to be synchronous. Given that SIMD based software implementations are usually asynchronous as well, even though they rarely complete asynchronously (this typically only happens in cases where the request was made from softirq context, while SIMD was already in use in the task context that it interrupted), these implementations are disregarded, and either the generic C version or another table based version implemented in assembler is selected instead. Since falling back to synchronous AES is not only a performance issue, but potentially a security issue as well (due to the fact that table based AES is not time invariant), let's fix this, by allocating an ordinary skcipher as the fallback, and invoke it with the completion routine that was given to the outer request. Signed-off-by: Ard Biesheuvel --- drivers/crypto/mxs-dcp.c | 33 ++++++++++---------- 1 file changed, 17 insertions(+), 16 deletions(-) diff --git a/drivers/crypto/mxs-dcp.c b/drivers/crypto/mxs-dcp.c index d84530293036..909a7eb748e3 100644 --- a/drivers/crypto/mxs-dcp.c +++ b/drivers/crypto/mxs-dcp.c @@ -97,7 +97,7 @@ struct dcp_async_ctx { unsigned int hot:1; /* Crypto-specific context */ - struct crypto_sync_skcipher *fallback; + struct crypto_skcipher *fallback; unsigned int key_len; uint8_t key[AES_KEYSIZE_128]; }; @@ -105,6 +105,7 @@ struct dcp_async_ctx { struct dcp_aes_req_ctx { unsigned int enc:1; unsigned int ecb:1; + struct skcipher_request fallback_req; // keep at the end }; struct dcp_sha_req_ctx { @@ -426,21 +427,20 @@ static int dcp_chan_thread_aes(void *data) static int mxs_dcp_block_fallback(struct skcipher_request *req, int enc) { struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); + struct dcp_aes_req_ctx *rctx = skcipher_request_ctx(req); struct dcp_async_ctx *ctx = crypto_skcipher_ctx(tfm); - SYNC_SKCIPHER_REQUEST_ON_STACK(subreq, ctx->fallback); int ret; - skcipher_request_set_sync_tfm(subreq, ctx->fallback); - skcipher_request_set_callback(subreq, req->base.flags, NULL, NULL); - skcipher_request_set_crypt(subreq, req->src, req->dst, + skcipher_request_set_tfm(&rctx->fallback_req, ctx->fallback); + skcipher_request_set_callback(&rctx->fallback_req, req->base.flags, + req->base.complete, req->base.data); + skcipher_request_set_crypt(&rctx->fallback_req, req->src, req->dst, req->cryptlen, req->iv); if (enc) - ret = crypto_skcipher_encrypt(subreq); + ret = crypto_skcipher_encrypt(&rctx->fallback_req); else - ret = crypto_skcipher_decrypt(subreq); - - skcipher_request_zero(subreq); + ret = crypto_skcipher_decrypt(&rctx->fallback_req); return ret; } @@ -510,24 +510,25 @@ static int mxs_dcp_aes_setkey(struct crypto_skcipher *tfm, const u8 *key, * but is supported by in-kernel software implementation, we use * software fallback. */ - crypto_sync_skcipher_clear_flags(actx->fallback, CRYPTO_TFM_REQ_MASK); - crypto_sync_skcipher_set_flags(actx->fallback, + crypto_skcipher_clear_flags(actx->fallback, CRYPTO_TFM_REQ_MASK); + crypto_skcipher_set_flags(actx->fallback, tfm->base.crt_flags & CRYPTO_TFM_REQ_MASK); - return crypto_sync_skcipher_setkey(actx->fallback, key, len); + return crypto_skcipher_setkey(actx->fallback, key, len); } static int mxs_dcp_aes_fallback_init_tfm(struct crypto_skcipher *tfm) { const char *name = crypto_tfm_alg_name(crypto_skcipher_tfm(tfm)); struct dcp_async_ctx *actx = crypto_skcipher_ctx(tfm); - struct crypto_sync_skcipher *blk; + struct crypto_skcipher *blk; - blk = crypto_alloc_sync_skcipher(name, 0, CRYPTO_ALG_NEED_FALLBACK); + blk = crypto_alloc_skcipher(name, 0, CRYPTO_ALG_NEED_FALLBACK); if (IS_ERR(blk)) return PTR_ERR(blk); actx->fallback = blk; - crypto_skcipher_set_reqsize(tfm, sizeof(struct dcp_aes_req_ctx)); + crypto_skcipher_set_reqsize(tfm, sizeof(struct dcp_aes_req_ctx) + + crypto_skcipher_reqsize(blk)); return 0; } @@ -535,7 +536,7 @@ static void mxs_dcp_aes_fallback_exit_tfm(struct crypto_skcipher *tfm) { struct dcp_async_ctx *actx = crypto_skcipher_ctx(tfm); - crypto_free_sync_skcipher(actx->fallback); + crypto_free_skcipher(actx->fallback); } /* -- 2.27.0 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel