From patchwork Sat Jun 27 08:36:21 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ard Biesheuvel X-Patchwork-Id: 11629435 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 53D4D14E3 for ; Sat, 27 Jun 2020 08:37:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3CC0F20DD4 for ; Sat, 27 Jun 2020 08:37:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1593247046; bh=SZYJbEe8mCowaOS/Sy7cfSLq4/DGTZWmD8C72wZYJ5s=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Aa8UkN8ntb5NYacUIPTwbKIv1VZI3lXaalRGMyYZ5/equ07SGY+/+Qg7HdbKjc82b aPLF9JOvUhVJ/QKYehbhjdxI/rxhvYxH+7cwCU48FfJe5PFZ/jAF/HA654C/Fs7ATi E5PCYBxbkvJ9oea9uR8BHvpGZy+lx8qCKAtwFCVU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726438AbgF0IhZ (ORCPT ); Sat, 27 Jun 2020 04:37:25 -0400 Received: from mail.kernel.org ([198.145.29.99]:33388 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726086AbgF0IhZ (ORCPT ); Sat, 27 Jun 2020 04:37:25 -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 915F82088E; Sat, 27 Jun 2020 08:37:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1593247044; bh=SZYJbEe8mCowaOS/Sy7cfSLq4/DGTZWmD8C72wZYJ5s=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Bh0tF48/Qe5q5cXU4io8BawjUbNBLGrYJCtI8EFMlOj/mpvtvs4b9vxH2eufj5xfe wE6ZPLkwV8tLLl7/4OxD7gTRr+bliN0kRrWnhxPT79p+b8cWdwyWeGXNQyQOEU4Xyx WGkWT79LYToF19D84UiTwTCasT2xakeRJILuW1AA= 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 11/13] crypto: qce - permit asynchronous skcipher as fallback Date: Sat, 27 Jun 2020 10:36:21 +0200 Message-Id: <20200627083623.2428333-12-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 qce driver implements asynchronous versions of ecb(aes), cbc(aes)and xts(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/qce/cipher.h | 3 ++- drivers/crypto/qce/skcipher.c | 27 ++++++++++---------- 2 files changed, 16 insertions(+), 14 deletions(-) diff --git a/drivers/crypto/qce/cipher.h b/drivers/crypto/qce/cipher.h index 7770660bc853..cffa9fc628ff 100644 --- a/drivers/crypto/qce/cipher.h +++ b/drivers/crypto/qce/cipher.h @@ -14,7 +14,7 @@ struct qce_cipher_ctx { u8 enc_key[QCE_MAX_KEY_SIZE]; unsigned int enc_keylen; - struct crypto_sync_skcipher *fallback; + struct crypto_skcipher *fallback; }; /** @@ -43,6 +43,7 @@ struct qce_cipher_reqctx { struct sg_table src_tbl; struct scatterlist *src_sg; unsigned int cryptlen; + struct skcipher_request fallback_req; // keep at the end }; static inline struct qce_alg_template *to_cipher_tmpl(struct crypto_skcipher *tfm) diff --git a/drivers/crypto/qce/skcipher.c b/drivers/crypto/qce/skcipher.c index 9412433f3b21..265afae29901 100644 --- a/drivers/crypto/qce/skcipher.c +++ b/drivers/crypto/qce/skcipher.c @@ -178,7 +178,7 @@ static int qce_skcipher_setkey(struct crypto_skcipher *ablk, const u8 *key, break; } - ret = crypto_sync_skcipher_setkey(ctx->fallback, key, keylen); + ret = crypto_skcipher_setkey(ctx->fallback, key, keylen); if (!ret) ctx->enc_keylen = keylen; return ret; @@ -235,16 +235,15 @@ static int qce_skcipher_crypt(struct skcipher_request *req, int encrypt) req->cryptlen <= aes_sw_max_len) || (IS_XTS(rctx->flags) && req->cryptlen > QCE_SECTOR_SIZE && req->cryptlen % QCE_SECTOR_SIZE))) { - SYNC_SKCIPHER_REQUEST_ON_STACK(subreq, ctx->fallback); - - 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, - req->cryptlen, req->iv); - ret = encrypt ? crypto_skcipher_encrypt(subreq) : - crypto_skcipher_decrypt(subreq); - skcipher_request_zero(subreq); + 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); + ret = encrypt ? crypto_skcipher_encrypt(&rctx->fallback_req) : + crypto_skcipher_decrypt(&rctx->fallback_req); return ret; } @@ -275,8 +274,10 @@ static int qce_skcipher_init_fallback(struct crypto_skcipher *tfm) struct qce_cipher_ctx *ctx = crypto_skcipher_ctx(tfm); qce_skcipher_init(tfm); - ctx->fallback = crypto_alloc_sync_skcipher(crypto_tfm_alg_name(&tfm->base), + ctx->fallback = crypto_alloc_skcipher(crypto_tfm_alg_name(&tfm->base), 0, CRYPTO_ALG_NEED_FALLBACK); + crypto_skcipher_set_reqsize(tfm, sizeof(struct qce_cipher_reqctx) + + crypto_skcipher_reqsize(ctx->fallback)); return PTR_ERR_OR_ZERO(ctx->fallback); } @@ -284,7 +285,7 @@ static void qce_skcipher_exit(struct crypto_skcipher *tfm) { struct qce_cipher_ctx *ctx = crypto_skcipher_ctx(tfm); - crypto_free_sync_skcipher(ctx->fallback); + crypto_free_skcipher(ctx->fallback); } struct qce_skcipher_def {