From patchwork Sat Jun 27 08:36:20 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ard Biesheuvel X-Patchwork-Id: 211304 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 C7381C433E5 for ; Sat, 27 Jun 2020 08:37:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A66B4212CC for ; Sat, 27 Jun 2020 08:37:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1593247041; bh=EGar2rBAa9p0EmyWbgXPPJUEijUxQLN5bxRPFqvMCTY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=uYI6BYHkhxqujWPjvFD/hWZDLU/55nrVyAMgavcYCkQ3LI80ugaj4uQE5JyGcSFx/ HH6oIsc5IuXGfKi+epq6qeeCVdX5xdIDuB0qDucKnOjKfbkbLLsWDeHcJWr5XlYMWx mevz8udJ5A32Pup3otnKAqUYHegTkfDBc6O0woO8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726429AbgF0IhV (ORCPT ); Sat, 27 Jun 2020 04:37:21 -0400 Received: from mail.kernel.org ([198.145.29.99]:33300 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726086AbgF0IhU (ORCPT ); Sat, 27 Jun 2020 04:37:20 -0400 Received: from dogfood.home (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 26F03207FC; Sat, 27 Jun 2020 08:37:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1593247040; bh=EGar2rBAa9p0EmyWbgXPPJUEijUxQLN5bxRPFqvMCTY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=O43pL46JHTcyFNkA22Y4nrjz3lRUgG/5t9y/PrLc9W2Tqn8PSGrYu/bnqJzG3qDcl nQGyjZS/YFlGgazwQq6VSynO+h/ICt0LjNQzOt7gEtCwS6v4U695FstrLSsd5I2/DY 0yrids79ui3vTeIfzDqlwifzLaPp5993qdI+eQ90= 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 , Tero Kristo , Matthias Brugger Subject: [PATCH v2 10/13] crypto: picoxcell - permit asynchronous skcipher as fallback Date: Sat, 27 Jun 2020 10:36:20 +0200 Message-Id: <20200627083623.2428333-11-ardb@kernel.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200627083623.2428333-1-ardb@kernel.org> References: <20200627083623.2428333-1-ardb@kernel.org> MIME-Version: 1.0 Sender: linux-omap-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-omap@vger.kernel.org Even though the picoxcell 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/picoxcell_crypto.c | 34 +++++++++++--------- 1 file changed, 19 insertions(+), 15 deletions(-) diff --git a/drivers/crypto/picoxcell_crypto.c b/drivers/crypto/picoxcell_crypto.c index 7384e91c8b32..eea75c7cbdf2 100644 --- a/drivers/crypto/picoxcell_crypto.c +++ b/drivers/crypto/picoxcell_crypto.c @@ -86,6 +86,7 @@ struct spacc_req { dma_addr_t src_addr, dst_addr; struct spacc_ddt *src_ddt, *dst_ddt; void (*complete)(struct spacc_req *req); + struct skcipher_request fallback_req; // keep at the end }; struct spacc_aead { @@ -158,7 +159,7 @@ struct spacc_ablk_ctx { * The fallback cipher. If the operation can't be done in hardware, * fallback to a software version. */ - struct crypto_sync_skcipher *sw_cipher; + struct crypto_skcipher *sw_cipher; }; /* AEAD cipher context. */ @@ -792,13 +793,13 @@ static int spacc_aes_setkey(struct crypto_skcipher *cipher, const u8 *key, * Set the fallback transform to use the same request flags as * the hardware transform. */ - crypto_sync_skcipher_clear_flags(ctx->sw_cipher, + crypto_skcipher_clear_flags(ctx->sw_cipher, CRYPTO_TFM_REQ_MASK); - crypto_sync_skcipher_set_flags(ctx->sw_cipher, + crypto_skcipher_set_flags(ctx->sw_cipher, cipher->base.crt_flags & CRYPTO_TFM_REQ_MASK); - err = crypto_sync_skcipher_setkey(ctx->sw_cipher, key, len); + err = crypto_skcipher_setkey(ctx->sw_cipher, key, len); if (err) goto sw_setkey_failed; } @@ -900,7 +901,7 @@ static int spacc_ablk_do_fallback(struct skcipher_request *req, struct crypto_tfm *old_tfm = crypto_skcipher_tfm(crypto_skcipher_reqtfm(req)); struct spacc_ablk_ctx *ctx = crypto_tfm_ctx(old_tfm); - SYNC_SKCIPHER_REQUEST_ON_STACK(subreq, ctx->sw_cipher); + struct spacc_req *dev_req = skcipher_request_ctx(req); int err; /* @@ -908,13 +909,13 @@ static int spacc_ablk_do_fallback(struct skcipher_request *req, * the ciphering has completed, put the old transform back into the * request. */ - skcipher_request_set_sync_tfm(subreq, ctx->sw_cipher); - skcipher_request_set_callback(subreq, req->base.flags, NULL, NULL); - skcipher_request_set_crypt(subreq, req->src, req->dst, + skcipher_request_set_tfm(&dev_req->fallback_req, ctx->sw_cipher); + skcipher_request_set_callback(&dev_req->fallback_req, req->base.flags, + req->base.complete, req->base.data); + skcipher_request_set_crypt(&dev_req->fallback_req, req->src, req->dst, req->cryptlen, req->iv); - err = is_encrypt ? crypto_skcipher_encrypt(subreq) : - crypto_skcipher_decrypt(subreq); - skcipher_request_zero(subreq); + err = is_encrypt ? crypto_skcipher_encrypt(&dev_req->fallback_req) : + crypto_skcipher_decrypt(&dev_req->fallback_req); return err; } @@ -1007,19 +1008,22 @@ static int spacc_ablk_init_tfm(struct crypto_skcipher *tfm) ctx->generic.flags = spacc_alg->type; ctx->generic.engine = engine; if (alg->base.cra_flags & CRYPTO_ALG_NEED_FALLBACK) { - ctx->sw_cipher = crypto_alloc_sync_skcipher( + ctx->sw_cipher = crypto_alloc_skcipher( alg->base.cra_name, 0, CRYPTO_ALG_NEED_FALLBACK); if (IS_ERR(ctx->sw_cipher)) { dev_warn(engine->dev, "failed to allocate fallback for %s\n", alg->base.cra_name); return PTR_ERR(ctx->sw_cipher); } + crypto_skcipher_set_reqsize(tfm, sizeof(struct spacc_req) + + crypto_skcipher_reqsize(ctx->sw_cipher)); + } else { + crypto_skcipher_set_reqsize(tfm, sizeof(struct spacc_req)); } + ctx->generic.key_offs = spacc_alg->key_offs; ctx->generic.iv_offs = spacc_alg->iv_offs; - crypto_skcipher_set_reqsize(tfm, sizeof(struct spacc_req)); - return 0; } @@ -1027,7 +1031,7 @@ static void spacc_ablk_exit_tfm(struct crypto_skcipher *tfm) { struct spacc_ablk_ctx *ctx = crypto_skcipher_ctx(tfm); - crypto_free_sync_skcipher(ctx->sw_cipher); + crypto_free_skcipher(ctx->sw_cipher); } static int spacc_ablk_encrypt(struct skcipher_request *req)