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 9D9A8C433E0 for ; Tue, 7 Jul 2020 06:33:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 78E672074F for ; Tue, 7 Jul 2020 06:33:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1594103610; bh=IfoJQfcz0Zm1QSESqy4YEJnncc0TZMao0pTV9CEAQXY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=ltBbxXxBx3C3jsO3ykmCnoxILki5StAo0NNVioPfcEA6nVWH84bbWQZGkFmm9Idza +zMXH/5zsZtrMKL/rtoTKs5oOc1sF23d43oEnPvRbAXqUQ0gCfGDD/lzTkQfo5jjfq tAJlnLuErjFh3Tz5y9b912y9bUtuN7H63KVzFHn8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728117AbgGGGd3 (ORCPT ); Tue, 7 Jul 2020 02:33:29 -0400 Received: from mail.kernel.org ([198.145.29.99]:33164 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727886AbgGGGd2 (ORCPT ); Tue, 7 Jul 2020 02:33:28 -0400 Received: from e123331-lin.nice.arm.com (adsl-70.109.242.21.tellas.gr [109.242.21.70]) (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 5D3BA206E9; Tue, 7 Jul 2020 06:33:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1594103608; bh=IfoJQfcz0Zm1QSESqy4YEJnncc0TZMao0pTV9CEAQXY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Fd1bXXMIMwDAlgt/o656CwsB4/AlhMBurCSzFojtq766cs934rdteCMxTiK3Bte/R KG0QyB5ppwyd8EWKlW2EMAvv1CnCDxyH/0vVKTO3JuwwgEZsKWUUzfhn8KhONVzInX fKYcxZ4LT1g/dEfrao+X5yMk0cD3vdQ5J+kx27Og= From: Ard Biesheuvel To: linux-crypto@vger.kernel.org Cc: Ard Biesheuvel , Corentin Labbe , Corentin Labbe , Herbert Xu , "David S. Miller" , Maxime Ripard , Chen-Yu Tsai , Tom Lendacky , John Allen , 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 , =?UTF-8?q?Horia=20Geant=C4=83?= , linux-arm-kernel@lists.infradead.org, linux-omap@vger.kernel.org, linux-amlogic@lists.infradead.org Subject: [PATCH v4 07/13] crypto: ccp - permit asynchronous skcipher as fallback Date: Tue, 7 Jul 2020 09:31:57 +0300 Message-Id: <20200707063203.5018-8-ardb@kernel.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200707063203.5018-1-ardb@kernel.org> References: <20200707063203.5018-1-ardb@kernel.org> Sender: linux-omap-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-omap@vger.kernel.org Even though the ccp driver implements an asynchronous version of xts(aes), the fallback it allocates is 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/ccp/ccp-crypto-aes-xts.c | 33 ++++++++++---------- drivers/crypto/ccp/ccp-crypto.h | 4 ++- 2 files changed, 19 insertions(+), 18 deletions(-) diff --git a/drivers/crypto/ccp/ccp-crypto-aes-xts.c b/drivers/crypto/ccp/ccp-crypto-aes-xts.c index 04b2517df955..959168a7ac59 100644 --- a/drivers/crypto/ccp/ccp-crypto-aes-xts.c +++ b/drivers/crypto/ccp/ccp-crypto-aes-xts.c @@ -98,7 +98,7 @@ static int ccp_aes_xts_setkey(struct crypto_skcipher *tfm, const u8 *key, ctx->u.aes.key_len = key_len / 2; sg_init_one(&ctx->u.aes.key_sg, ctx->u.aes.key, key_len); - return crypto_sync_skcipher_setkey(ctx->u.aes.tfm_skcipher, key, key_len); + return crypto_skcipher_setkey(ctx->u.aes.tfm_skcipher, key, key_len); } static int ccp_aes_xts_crypt(struct skcipher_request *req, @@ -145,20 +145,19 @@ static int ccp_aes_xts_crypt(struct skcipher_request *req, (ctx->u.aes.key_len != AES_KEYSIZE_256)) fallback = 1; if (fallback) { - SYNC_SKCIPHER_REQUEST_ON_STACK(subreq, - ctx->u.aes.tfm_skcipher); - /* Use the fallback to process the request for any * unsupported unit sizes or key sizes */ - skcipher_request_set_sync_tfm(subreq, ctx->u.aes.tfm_skcipher); - 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->u.aes.tfm_skcipher); + 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; } @@ -198,13 +197,12 @@ static int ccp_aes_xts_decrypt(struct skcipher_request *req) static int ccp_aes_xts_init_tfm(struct crypto_skcipher *tfm) { struct ccp_ctx *ctx = crypto_skcipher_ctx(tfm); - struct crypto_sync_skcipher *fallback_tfm; + struct crypto_skcipher *fallback_tfm; ctx->complete = ccp_aes_xts_complete; ctx->u.aes.key_len = 0; - fallback_tfm = crypto_alloc_sync_skcipher("xts(aes)", 0, - CRYPTO_ALG_ASYNC | + fallback_tfm = crypto_alloc_skcipher("xts(aes)", 0, CRYPTO_ALG_NEED_FALLBACK); if (IS_ERR(fallback_tfm)) { pr_warn("could not load fallback driver xts(aes)\n"); @@ -212,7 +210,8 @@ static int ccp_aes_xts_init_tfm(struct crypto_skcipher *tfm) } ctx->u.aes.tfm_skcipher = fallback_tfm; - crypto_skcipher_set_reqsize(tfm, sizeof(struct ccp_aes_req_ctx)); + crypto_skcipher_set_reqsize(tfm, sizeof(struct ccp_aes_req_ctx) + + crypto_skcipher_reqsize(fallback_tfm)); return 0; } @@ -221,7 +220,7 @@ static void ccp_aes_xts_exit_tfm(struct crypto_skcipher *tfm) { struct ccp_ctx *ctx = crypto_skcipher_ctx(tfm); - crypto_free_sync_skcipher(ctx->u.aes.tfm_skcipher); + crypto_free_skcipher(ctx->u.aes.tfm_skcipher); } static int ccp_register_aes_xts_alg(struct list_head *head, diff --git a/drivers/crypto/ccp/ccp-crypto.h b/drivers/crypto/ccp/ccp-crypto.h index 90a009e6b5c1..aed3d2192d01 100644 --- a/drivers/crypto/ccp/ccp-crypto.h +++ b/drivers/crypto/ccp/ccp-crypto.h @@ -89,7 +89,7 @@ static inline struct ccp_crypto_ahash_alg * /***** AES related defines *****/ struct ccp_aes_ctx { /* Fallback cipher for XTS with unsupported unit sizes */ - struct crypto_sync_skcipher *tfm_skcipher; + struct crypto_skcipher *tfm_skcipher; enum ccp_engine engine; enum ccp_aes_type type; @@ -121,6 +121,8 @@ struct ccp_aes_req_ctx { u8 rfc3686_iv[AES_BLOCK_SIZE]; struct ccp_cmd cmd; + + struct skcipher_request fallback_req; // keep at the end }; struct ccp_aes_cmac_req_ctx { -- 2.17.1