From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wr1-f66.google.com ([209.85.221.66]:42163 "EHLO mail-wr1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726271AbfFZUk5 (ORCPT ); Wed, 26 Jun 2019 16:40:57 -0400 Received: by mail-wr1-f66.google.com with SMTP id x17so4249328wrl.9 for ; Wed, 26 Jun 2019 13:40:56 -0700 (PDT) From: Ard Biesheuvel Subject: [PATCH v5 3/7] md: dm-crypt: infer ESSIV block cipher from cipher string directly Date: Wed, 26 Jun 2019 22:40:43 +0200 Message-Id: <20190626204047.32131-4-ard.biesheuvel@linaro.org> In-Reply-To: <20190626204047.32131-1-ard.biesheuvel@linaro.org> References: <20190626204047.32131-1-ard.biesheuvel@linaro.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-fscrypt-owner@vger.kernel.org To: linux-crypto@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org, Ard Biesheuvel , Herbert Xu , Eric Biggers , dm-devel@redhat.com, linux-fscrypt@vger.kernel.org, Gilad Ben-Yossef , Milan Broz List-ID: Instead of allocating a crypto skcipher tfm 'foo' and attempting to infer the encapsulated block cipher from the driver's 'name' field, directly parse the string that we used to allocated the tfm. These are always identical (unless the allocation failed, in which case we bail anyway), but using the string allows us to use it in the allocation, which is something we will need when switching to the 'essiv' crypto API template. Signed-off-by: Ard Biesheuvel --- drivers/md/dm-crypt.c | 35 +++++++++----------- 1 file changed, 15 insertions(+), 20 deletions(-) diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c index 1b16d34bb785..f001f1104cb5 100644 --- a/drivers/md/dm-crypt.c +++ b/drivers/md/dm-crypt.c @@ -2321,25 +2321,17 @@ static int crypt_ctr_ivmode(struct dm_target *ti, const char *ivmode) * The cc->cipher is currently used only in ESSIV. * This should be probably done by crypto-api calls (once available...) */ -static int crypt_ctr_blkdev_cipher(struct crypt_config *cc) +static int crypt_ctr_blkdev_cipher(struct crypt_config *cc, char *alg_name) { - const char *alg_name = NULL; char *start, *end; if (crypt_integrity_aead(cc)) { - alg_name = crypto_tfm_alg_name(crypto_aead_tfm(any_tfm_aead(cc))); - if (!alg_name) - return -EINVAL; if (crypt_integrity_hmac(cc)) { alg_name = strchr(alg_name, ','); if (!alg_name) return -EINVAL; } alg_name++; - } else { - alg_name = crypto_tfm_alg_name(crypto_skcipher_tfm(any_tfm(cc))); - if (!alg_name) - return -EINVAL; } start = strchr(alg_name, '('); @@ -2434,6 +2426,20 @@ 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 (crypt_integrity_aead(cc)) { + ret = crypt_ctr_auth_cipher(cc, cipher_api); + if (ret < 0) { + ti->error = "Invalid AEAD cipher spec"; + return -ENOMEM; + } + } + + ret = crypt_ctr_blkdev_cipher(cc, cipher_api); + if (ret < 0) { + ti->error = "Cannot allocate cipher string"; + return -ENOMEM; + } + cc->key_parts = cc->tfms_count; /* Allocate cipher */ @@ -2445,21 +2451,10 @@ static int crypt_ctr_cipher_new(struct dm_target *ti, char *cipher_in, char *key /* Alloc AEAD, can be used only in new format. */ if (crypt_integrity_aead(cc)) { - ret = crypt_ctr_auth_cipher(cc, cipher_api); - if (ret < 0) { - ti->error = "Invalid AEAD cipher spec"; - return -ENOMEM; - } cc->iv_size = crypto_aead_ivsize(any_tfm_aead(cc)); } else cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc)); - ret = crypt_ctr_blkdev_cipher(cc); - if (ret < 0) { - ti->error = "Cannot allocate cipher string"; - return -ENOMEM; - } - return 0; } -- 2.20.1