From patchwork Fri Jun 21 08:09:16 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ard Biesheuvel X-Patchwork-Id: 167367 Delivered-To: patch@linaro.org Received: by 2002:a92:4782:0:0:0:0:0 with SMTP id e2csp418528ilk; Fri, 21 Jun 2019 01:09:42 -0700 (PDT) X-Google-Smtp-Source: APXvYqxz5uXSXavSySbKhXDU/Pm4GpucHSt+hikkMVMLMoDsTs3xsdusbR/SNFLRAjfZjOaDqB8+ X-Received: by 2002:a17:90a:cd03:: with SMTP id d3mr4672450pju.127.1561104582272; Fri, 21 Jun 2019 01:09:42 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1561104582; cv=none; d=google.com; s=arc-20160816; b=yFOQKUt6UAniBjJYRghMzgYcGD7fzbvi6yVi385PXfK1m4x5lPXjboOLEG3Tc9JFUG R1aTaIQxyTmPYiP6DbKQcHba/+CXO2FE3Gnfn9jnY2bplQktlfMtCp8evO+bPkY8UnHv 3FMzM1DDAGm9b9WVDwIoLFY05M7BBgTUFWEjHLdMTD20XHXY0Ptyq2aB/VlJ6NjNuxzi VfWE8o1/YpJrGfjTJHG0MLXNFcaXRdTGJZd7ctHlV/aGlyDJFOTdb/24rv3QmMIPzxJH ViMXMOKoYK2DOlJl+QIAvxhJy9d1B/qPqFEK8GwBlyWO5x+2T662S5K7FtVEaQK7l+Mw CNlQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:reply-to:references:in-reply-to :message-id:date:subject:cc:to:from; bh=ekInj981tkIgDeGFSBxRyrAwj6RO+kwdI0B8MaSZNuI=; b=q5mqEnzTWMY4YDUY6x+zLIZKLgI472wtP4BoykGj2/RtANAOWNcWgx/wDZkb3glrW3 Kb5zCZMBXuzFQygqZ+sRz8WaEYbFFKskqb7+JdLpOBf1DXjcNd51wXFoXSLDVANPknfy ZQM7c/9tCMxCU4DazxDVRi2ps23HTXyh097fDklRzdO3o0r5uRmIfdq9VLE25u06jI/e RYWP4b/SQjnOb3gnQxnQb8pIQ5ddru7OjejP+673GNwTRQPzsdYI/W7kEUPggPz0aBmi U/P8gA/HkGtApJAQO+PXwdiF5v8dJNJA83qZCKFadm9Yb7GJvnKS7WM8WCQXaitd4dhg SZiA== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-crypto-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-crypto-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id f63si2062053plf.224.2019.06.21.01.09.41; Fri, 21 Jun 2019 01:09:42 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-crypto-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-crypto-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-crypto-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726340AbfFUIJl (ORCPT + 3 others); Fri, 21 Jun 2019 04:09:41 -0400 Received: from foss.arm.com ([217.140.110.172]:49776 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726030AbfFUIJl (ORCPT ); Fri, 21 Jun 2019 04:09:41 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 2EFF013A1; Fri, 21 Jun 2019 01:09:40 -0700 (PDT) Received: from e111045-lin.arm.com (unknown [10.37.10.16]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 859FE3F246; Fri, 21 Jun 2019 01:09:38 -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 v4 4/6] md: dm-crypt: switch to ESSIV crypto API template Date: Fri, 21 Jun 2019 10:09:16 +0200 Message-Id: <20190621080918.22809-5-ard.biesheuvel@arm.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190621080918.22809-1-ard.biesheuvel@arm.com> References: <20190621080918.22809-1-ard.biesheuvel@arm.com> Reply-To: ard.biesheuvel@linaro.org Sender: linux-crypto-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org From: Ard Biesheuvel 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 | 208 +++----------------- 2 files changed, 31 insertions(+), 178 deletions(-) -- 2.17.1 diff --git a/drivers/md/Kconfig b/drivers/md/Kconfig index 45254b3ef715..30ca87cf25db 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 f001f1104cb5..12d28880ec34 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; @@ -323,161 +315,6 @@ 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; - - memset(iv, 0, cc->iv_size); - *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector); - crypto_cipher_encrypt_one(essiv_tfm, iv, iv); - - return 0; -} - static int crypt_iv_benbi_ctr(struct crypt_config *cc, struct dm_target *ti, const char *opts) { @@ -853,14 +690,6 @@ static const struct crypt_iv_operations crypt_iv_plain64be_ops = { .generator = crypt_iv_plain64be_gen }; -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 -}; - static const struct crypt_iv_operations crypt_iv_benbi_ops = { .ctr = crypt_iv_benbi_ctr, .dtr = crypt_iv_benbi_dtr, @@ -2283,7 +2112,7 @@ static int crypt_ctr_ivmode(struct dm_target *ti, const char *ivmode) else if (strcmp(ivmode, "plain64be") == 0) cc->iv_gen_ops = &crypt_iv_plain64be_ops; else if (strcmp(ivmode, "essiv") == 0) - cc->iv_gen_ops = &crypt_iv_essiv_ops; + cc->iv_gen_ops = &crypt_iv_plain64_ops; else if (strcmp(ivmode, "benbi") == 0) cc->iv_gen_ops = &crypt_iv_benbi_ops; else if (strcmp(ivmode, "null") == 0) @@ -2397,7 +2226,7 @@ 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; @@ -2435,9 +2264,19 @@ static int crypt_ctr_cipher_new(struct dm_target *ti, char *cipher_in, char *key } ret = crypt_ctr_blkdev_cipher(cc, cipher_api); - if (ret < 0) { - ti->error = "Cannot allocate cipher string"; - return -ENOMEM; + if (ret < 0) + goto bad_mem; + + 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,%s)", + cipher_api, cc->cipher, *ivopts); + if (ret < 0) + goto bad_mem; + cipher_api = buf; } cc->key_parts = cc->tfms_count; @@ -2456,6 +2295,9 @@ static int crypt_ctr_cipher_new(struct dm_target *ti, char *cipher_in, char *key cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc)); return 0; +bad_mem: + ti->error = "Cannot allocate cipher string"; + return -ENOMEM; } static int crypt_ctr_cipher_old(struct dm_target *ti, char *cipher_in, char *key, @@ -2515,8 +2357,18 @@ 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 (*ivmode && !strcmp(*ivmode, "essiv")) { + if (!*ivopts) { + ti->error = "Digest algorithm missing for ESSIV mode"; + return -EINVAL; + } + ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME, + "essiv(%s(%s),%s,%s)", chainmode, cipher, + cipher, *ivopts); + } else { + ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME, + "%s(%s)", chainmode, cipher); + } if (ret < 0) { kfree(cipher_api); goto bad_mem;