From patchwork Thu Jun 25 12:42:50 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ard Biesheuvel X-Patchwork-Id: 11625145 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id C8BC96C1 for ; Thu, 25 Jun 2020 12:46:44 +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 A11ED206BE for ; Thu, 25 Jun 2020 12:46:44 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="Z7A44QaJ"; 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 A11ED206BE 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+patchwork-linux-arm=patchwork.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=s9LwGseFjj1TXqkRFUrADwlJVfC3tqJjYyBkFF4l4DM=; b=Z7A44QaJ6rWuagXNNEkKZSK9w 1HBSuIb1VCvLSCioCf0uysTWAbzGmhhpF0cDEhaAf8CRJPs0Vc4+F83xYSqQoL5CeZ3cxmAubfprY T5lC+C9c68DN97RCacHPNdcKON96R4p49HOy6Ml40cN2dJGC72EbLuA64Uo5pxxhZuZH7HiUYe6EM YrKTQuxEDI5Zos79uA12tlk0GpPlmXluLmPITKRQ/KXMsmj7mj8Ew5vjh3EMQd2vMtPjFc99aZS/s nxcf70aTg0zEh6pN7wPphQqts2RSsUpLPZ/kuOxMyEfs7wwUuM1Mk7OmJdwUnmdRWagLTFusvBy7G cgGnh9CKg==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1joRF1-0005pN-Ll; Thu, 25 Jun 2020 12:44:31 +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-Spam-Note: CRM114 invocation failed X-Spam-Score: -5.2 (-----) X-Spam-Report: SpamAssassin version 3.4.4 on merlin.infradead.org summary: Content analysis details: (-5.2 points) pts rule name description ---- ---------------------- -------------------------------------------------- -5.0 RCVD_IN_DNSWL_HI RBL: Sender listed at https://www.dnswl.org/, high trust [198.145.29.99 listed in list.dnswl.org] 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record -0.0 SPF_PASS SPF: sender matches SPF record -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature -0.1 DKIM_VALID_EF Message has a valid DKIM or DK signature from envelope-from domain -0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from author's domain 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily valid -0.0 DKIMWL_WL_HIGH DKIMwl.org - Whitelisted High sender 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 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.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); } /*