From patchwork Sat Aug 10 09:40:49 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ard Biesheuvel X-Patchwork-Id: 11088475 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id BB2081850 for ; Sat, 10 Aug 2019 09:41:23 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A5F3622638 for ; Sat, 10 Aug 2019 09:41:23 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 986F022A6F; Sat, 10 Aug 2019 09:41:23 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id EE89D22638 for ; Sat, 10 Aug 2019 09:41:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726084AbfHJJlW (ORCPT ); Sat, 10 Aug 2019 05:41:22 -0400 Received: from mail-wr1-f65.google.com ([209.85.221.65]:37065 "EHLO mail-wr1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725468AbfHJJlW (ORCPT ); Sat, 10 Aug 2019 05:41:22 -0400 Received: by mail-wr1-f65.google.com with SMTP id b3so7964264wro.4 for ; Sat, 10 Aug 2019 02:41:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=56ampqLUPOTSSPtRfg1LVltpdcwpm+t0SppiwG6MdWQ=; b=GtQ0dmnE804VqZHh5jpqC+lwABILW62Bwd4q22wI4C3aSaKdw2ws7yrXbO6G0U/yZv x3TFCyyz9CYCbp4twTvNVOa4W1BIsQFUts+5gFOCfeXCWRe1HsgfR5O9akciY6JvV2QK 0pg0aeAr4UwOPx1u9zop17esAVjs7v5TEBz7piU3Ch8cg/RUKelMiMVyDpPanAuBzDup BMDQIo0N9LJiSZNq+8yKaiWbFUgKcw2EH7rOF+NdF0+8eoRNacK+THiPPDSn/jLefKwK 6wO+RyJKqjtrXoDJsnCaeWZyjLqOUVkpG7q8FtjpUgWIJEFfACT6jRylagcTKshsuDB9 CyXw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=56ampqLUPOTSSPtRfg1LVltpdcwpm+t0SppiwG6MdWQ=; b=bpO6kiz729eEkql14oESJrd50YFmq3hJyzLXZOHXlyAjwGCVUXUH3HHfzyrFEq6MBL RZgRMPGab4dL6SPZRB54iS4NEjnE+RJll7VJydxoOHksLRe0EX8q9RII5EfKf25zaBgq s2K3ThqMghnygozBHCkHghtWCZ4ln+IIM71ujY7O4aNLQIjuko4/ARWB5+2TO+g2BF/C mPpKwcJwlzd3wlO6PGmnz5s3jy48W6hidHDiC2bHleu34/0/L3w53d7SratWPjlOomzz 7mbQq6ZBDThIuK7NG6c3+uVJT2quYuZ2xydeiFQwovCYd+cYLgBij4XeViMSfoTj+npb xkDg== X-Gm-Message-State: APjAAAXVvbqLqjk0udZsOrHKb3p57GKDk7QqCARopK59ZTZTnPnCzjGs 9nBXCP/xDCwBtHwUCV8yyXEWJw== X-Google-Smtp-Source: APXvYqx8TarR2E/w3YsFQlNhncO6vBQ+Oh1CHshUY/lRklCURgAr7QGQ8rJZTO1J5S3gYPIG7JIT1Q== X-Received: by 2002:adf:db09:: with SMTP id s9mr1282160wri.214.1565430079837; Sat, 10 Aug 2019 02:41:19 -0700 (PDT) Received: from localhost.localdomain ([2a02:587:a407:da00:582f:8334:9cd9:7241]) by smtp.gmail.com with ESMTPSA id n16sm519883wmk.12.2019.08.10.02.41.18 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sat, 10 Aug 2019 02:41:19 -0700 (PDT) From: Ard Biesheuvel To: linux-crypto@vger.kernel.org Cc: Ard Biesheuvel , Herbert Xu , Eric Biggers , dm-devel@redhat.com, linux-fscrypt@vger.kernel.org, Gilad Ben-Yossef , Milan Broz Subject: [PATCH v9 3/7] md: dm-crypt: switch to ESSIV crypto API template Date: Sat, 10 Aug 2019 12:40:49 +0300 Message-Id: <20190810094053.7423-4-ard.biesheuvel@linaro.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190810094053.7423-1-ard.biesheuvel@linaro.org> References: <20190810094053.7423-1-ard.biesheuvel@linaro.org> Sender: linux-fscrypt-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fscrypt@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Replace the explicit ESSIV handling in the dm-crypt driver with calls into the crypto API, which now possesses the capability to perform this processing within the crypto subsystem. Signed-off-by: Ard Biesheuvel --- drivers/md/Kconfig | 1 + drivers/md/dm-crypt.c | 194 ++++---------------- 2 files changed, 33 insertions(+), 162 deletions(-) diff --git a/drivers/md/Kconfig b/drivers/md/Kconfig index 3834332f4963..b727e8f15264 100644 --- a/drivers/md/Kconfig +++ b/drivers/md/Kconfig @@ -271,6 +271,7 @@ config DM_CRYPT depends on BLK_DEV_DM select CRYPTO select CRYPTO_CBC + select CRYPTO_ESSIV ---help--- This device-mapper target allows you to create a device that transparently encrypts the data on it. You'll need to activate diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c index 48cd76c88d77..d3f2634f41a8 100644 --- a/drivers/md/dm-crypt.c +++ b/drivers/md/dm-crypt.c @@ -98,11 +98,6 @@ struct crypt_iv_operations { struct dm_crypt_request *dmreq); }; -struct iv_essiv_private { - struct crypto_shash *hash_tfm; - u8 *salt; -}; - struct iv_benbi_private { int shift; }; @@ -155,7 +150,6 @@ struct crypt_config { const struct crypt_iv_operations *iv_gen_ops; union { - struct iv_essiv_private essiv; struct iv_benbi_private benbi; struct iv_lmk_private lmk; struct iv_tcw_private tcw; @@ -165,8 +159,6 @@ struct crypt_config { unsigned short int sector_size; unsigned char sector_shift; - /* ESSIV: struct crypto_cipher *essiv_tfm */ - void *iv_private; union { struct crypto_skcipher **tfms; struct crypto_aead **tfms_aead; @@ -324,157 +316,15 @@ static int crypt_iv_plain64be_gen(struct crypt_config *cc, u8 *iv, return 0; } -/* Initialise ESSIV - compute salt but no local memory allocations */ -static int crypt_iv_essiv_init(struct crypt_config *cc) -{ - struct iv_essiv_private *essiv = &cc->iv_gen_private.essiv; - SHASH_DESC_ON_STACK(desc, essiv->hash_tfm); - struct crypto_cipher *essiv_tfm; - int err; - - desc->tfm = essiv->hash_tfm; - - err = crypto_shash_digest(desc, cc->key, cc->key_size, essiv->salt); - shash_desc_zero(desc); - if (err) - return err; - - essiv_tfm = cc->iv_private; - - err = crypto_cipher_setkey(essiv_tfm, essiv->salt, - crypto_shash_digestsize(essiv->hash_tfm)); - if (err) - return err; - - return 0; -} - -/* Wipe salt and reset key derived from volume key */ -static int crypt_iv_essiv_wipe(struct crypt_config *cc) -{ - struct iv_essiv_private *essiv = &cc->iv_gen_private.essiv; - unsigned salt_size = crypto_shash_digestsize(essiv->hash_tfm); - struct crypto_cipher *essiv_tfm; - int r, err = 0; - - memset(essiv->salt, 0, salt_size); - - essiv_tfm = cc->iv_private; - r = crypto_cipher_setkey(essiv_tfm, essiv->salt, salt_size); - if (r) - err = r; - - return err; -} - -/* Allocate the cipher for ESSIV */ -static struct crypto_cipher *alloc_essiv_cipher(struct crypt_config *cc, - struct dm_target *ti, - const u8 *salt, - unsigned int saltsize) -{ - struct crypto_cipher *essiv_tfm; - int err; - - /* Setup the essiv_tfm with the given salt */ - essiv_tfm = crypto_alloc_cipher(cc->cipher, 0, 0); - if (IS_ERR(essiv_tfm)) { - ti->error = "Error allocating crypto tfm for ESSIV"; - return essiv_tfm; - } - - if (crypto_cipher_blocksize(essiv_tfm) != cc->iv_size) { - ti->error = "Block size of ESSIV cipher does " - "not match IV size of block cipher"; - crypto_free_cipher(essiv_tfm); - return ERR_PTR(-EINVAL); - } - - err = crypto_cipher_setkey(essiv_tfm, salt, saltsize); - if (err) { - ti->error = "Failed to set key for ESSIV cipher"; - crypto_free_cipher(essiv_tfm); - return ERR_PTR(err); - } - - return essiv_tfm; -} - -static void crypt_iv_essiv_dtr(struct crypt_config *cc) -{ - struct crypto_cipher *essiv_tfm; - struct iv_essiv_private *essiv = &cc->iv_gen_private.essiv; - - crypto_free_shash(essiv->hash_tfm); - essiv->hash_tfm = NULL; - - kzfree(essiv->salt); - essiv->salt = NULL; - - essiv_tfm = cc->iv_private; - - if (essiv_tfm) - crypto_free_cipher(essiv_tfm); - - cc->iv_private = NULL; -} - -static int crypt_iv_essiv_ctr(struct crypt_config *cc, struct dm_target *ti, - const char *opts) -{ - struct crypto_cipher *essiv_tfm = NULL; - struct crypto_shash *hash_tfm = NULL; - u8 *salt = NULL; - int err; - - if (!opts) { - ti->error = "Digest algorithm missing for ESSIV mode"; - return -EINVAL; - } - - /* Allocate hash algorithm */ - hash_tfm = crypto_alloc_shash(opts, 0, 0); - if (IS_ERR(hash_tfm)) { - ti->error = "Error initializing ESSIV hash"; - err = PTR_ERR(hash_tfm); - goto bad; - } - - salt = kzalloc(crypto_shash_digestsize(hash_tfm), GFP_KERNEL); - if (!salt) { - ti->error = "Error kmallocing salt storage in ESSIV"; - err = -ENOMEM; - goto bad; - } - - cc->iv_gen_private.essiv.salt = salt; - cc->iv_gen_private.essiv.hash_tfm = hash_tfm; - - essiv_tfm = alloc_essiv_cipher(cc, ti, salt, - crypto_shash_digestsize(hash_tfm)); - if (IS_ERR(essiv_tfm)) { - crypt_iv_essiv_dtr(cc); - return PTR_ERR(essiv_tfm); - } - cc->iv_private = essiv_tfm; - - return 0; - -bad: - if (hash_tfm && !IS_ERR(hash_tfm)) - crypto_free_shash(hash_tfm); - kfree(salt); - return err; -} - static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv, struct dm_crypt_request *dmreq) { - struct crypto_cipher *essiv_tfm = cc->iv_private; - + /* + * ESSIV encryption of the IV is now handled by the crypto API, + * so just pass the plain sector number here. + */ memset(iv, 0, cc->iv_size); *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector); - crypto_cipher_encrypt_one(essiv_tfm, iv, iv); return 0; } @@ -898,10 +748,6 @@ static const struct crypt_iv_operations crypt_iv_plain64be_ops = { }; static const struct crypt_iv_operations crypt_iv_essiv_ops = { - .ctr = crypt_iv_essiv_ctr, - .dtr = crypt_iv_essiv_dtr, - .init = crypt_iv_essiv_init, - .wipe = crypt_iv_essiv_wipe, .generator = crypt_iv_essiv_gen }; @@ -2464,7 +2310,7 @@ static int crypt_ctr_cipher_new(struct dm_target *ti, char *cipher_in, char *key char **ivmode, char **ivopts) { struct crypt_config *cc = ti->private; - char *tmp, *cipher_api; + char *tmp, *cipher_api, buf[CRYPTO_MAX_ALG_NAME]; int ret = -EINVAL; cc->tfms_count = 1; @@ -2493,6 +2339,20 @@ static int crypt_ctr_cipher_new(struct dm_target *ti, char *cipher_in, char *key if (*ivmode && !strcmp(*ivmode, "lmk")) cc->tfms_count = 64; + if (*ivmode && !strcmp(*ivmode, "essiv")) { + if (!*ivopts) { + ti->error = "Digest algorithm missing for ESSIV mode"; + return -EINVAL; + } + ret = snprintf(buf, CRYPTO_MAX_ALG_NAME, "essiv(%s,%s)", + cipher_api, *ivopts); + if (ret < 0 || ret >= CRYPTO_MAX_ALG_NAME) { + ti->error = "Cannot allocate cipher string"; + return -ENOMEM; + } + cipher_api = buf; + } + cc->key_parts = cc->tfms_count; /* Allocate cipher */ @@ -2579,9 +2439,19 @@ static int crypt_ctr_cipher_old(struct dm_target *ti, char *cipher_in, char *key if (!cipher_api) goto bad_mem; - ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME, - "%s(%s)", chainmode, cipher); - if (ret < 0) { + if (*ivmode && !strcmp(*ivmode, "essiv")) { + if (!*ivopts) { + ti->error = "Digest algorithm missing for ESSIV mode"; + kfree(cipher_api); + return -EINVAL; + } + ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME, + "essiv(%s(%s),%s)", chainmode, cipher, *ivopts); + } else { + ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME, + "%s(%s)", chainmode, cipher); + } + if (ret < 0 || ret >= CRYPTO_MAX_ALG_NAME) { kfree(cipher_api); goto bad_mem; }