From patchwork Wed Sep 25 21:35:23 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Maxim Levitsky X-Patchwork-Id: 1167675 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=redhat.com Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 46dsHP1tvrz9sDB for ; Thu, 26 Sep 2019 07:52:49 +1000 (AEST) Received: from localhost ([::1]:57714 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iDFDL-0004u7-3J for incoming@patchwork.ozlabs.org; Wed, 25 Sep 2019 17:52:47 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:39073) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iDEy1-0006u4-8N for qemu-devel@nongnu.org; Wed, 25 Sep 2019 17:37:00 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iDExw-0006nz-Ro for qemu-devel@nongnu.org; Wed, 25 Sep 2019 17:36:54 -0400 Received: from mx1.redhat.com ([209.132.183.28]:47764) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1iDExR-0006YL-Im; Wed, 25 Sep 2019 17:36:26 -0400 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id A4A2E308212F; Wed, 25 Sep 2019 21:36:15 +0000 (UTC) Received: from maximlenovopc.usersys.redhat.com (unknown [10.35.206.49]) by smtp.corp.redhat.com (Postfix) with ESMTP id 444C519C5B; Wed, 25 Sep 2019 21:36:11 +0000 (UTC) From: Maxim Levitsky To: qemu-devel@nongnu.org Subject: [PATCH v2 09/13] qcrypto-luks: extract check and parse header Date: Thu, 26 Sep 2019 00:35:23 +0300 Message-Id: <20190925213527.9117-10-mlevitsk@redhat.com> In-Reply-To: <20190925213527.9117-1-mlevitsk@redhat.com> References: <20190925213527.9117-1-mlevitsk@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.47]); Wed, 25 Sep 2019 21:36:15 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Kevin Wolf , =?utf-8?q?Daniel_P=2E_Berrang=C3=A9?= , qemu-block@nongnu.org, John Snow , Markus Armbruster , Max Reitz , Maxim Levitsky Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" This is just to make qcrypto_block_luks_open more reasonable in size. Signed-off-by: Maxim Levitsky Reviewed-by: Daniel P. Berrangé --- crypto/block-luks.c | 223 +++++++++++++++++++++++++------------------- 1 file changed, 125 insertions(+), 98 deletions(-) diff --git a/crypto/block-luks.c b/crypto/block-luks.c index 47371edf13..fa799fd21d 100644 --- a/crypto/block-luks.c +++ b/crypto/block-luks.c @@ -500,6 +500,129 @@ qcrypto_block_luks_load_header(QCryptoBlock *block, return 0; } +/* + * Does basic sanity checks on the LUKS header + */ +static int +qcrypto_block_luks_check_header(const QCryptoBlockLUKS *luks, Error **errp) +{ + if (memcmp(luks->header.magic, qcrypto_block_luks_magic, + QCRYPTO_BLOCK_LUKS_MAGIC_LEN) != 0) { + error_setg(errp, "Volume is not in LUKS format"); + return -1; + } + + if (luks->header.version != QCRYPTO_BLOCK_LUKS_VERSION) { + error_setg(errp, "LUKS version %" PRIu32 " is not supported", + luks->header.version); + return -1; + } + return 0; +} + +/* + * Parses the crypto parameters that are stored in the LUKS header + */ + +static int +qcrypto_block_luks_parse_header(QCryptoBlockLUKS *luks, Error **errp) +{ + g_autofree char *cipher_mode = g_strdup(luks->header.cipher_mode); + char *ivgen_name, *ivhash_name; + Error *local_err = NULL; + + /* + * The cipher_mode header contains a string that we have + * to further parse, of the format + * + * -[:] + * + * eg cbc-essiv:sha256, cbc-plain64 + */ + ivgen_name = strchr(cipher_mode, '-'); + if (!ivgen_name) { + error_setg(errp, "Unexpected cipher mode string format %s", + luks->header.cipher_mode); + return -1; + } + *ivgen_name = '\0'; + ivgen_name++; + + ivhash_name = strchr(ivgen_name, ':'); + if (!ivhash_name) { + luks->ivgen_hash_alg = 0; + } else { + *ivhash_name = '\0'; + ivhash_name++; + + luks->ivgen_hash_alg = qcrypto_block_luks_hash_name_lookup(ivhash_name, + &local_err); + if (local_err) { + error_propagate(errp, local_err); + return -1; + } + } + + luks->cipher_mode = qcrypto_block_luks_cipher_mode_lookup(cipher_mode, + &local_err); + if (local_err) { + error_propagate(errp, local_err); + return -1; + } + + luks->cipher_alg = + qcrypto_block_luks_cipher_name_lookup(luks->header.cipher_name, + luks->cipher_mode, + luks->header.master_key_len, + &local_err); + if (local_err) { + error_propagate(errp, local_err); + return -1; + } + + luks->hash_alg = + qcrypto_block_luks_hash_name_lookup(luks->header.hash_spec, + &local_err); + if (local_err) { + error_propagate(errp, local_err); + return -1; + } + + luks->ivgen_alg = qcrypto_block_luks_ivgen_name_lookup(ivgen_name, + &local_err); + if (local_err) { + error_propagate(errp, local_err); + return -1; + } + + if (luks->ivgen_alg == QCRYPTO_IVGEN_ALG_ESSIV) { + if (!ivhash_name) { + error_setg(errp, "Missing IV generator hash specification"); + return -1; + } + luks->ivgen_cipher_alg = + qcrypto_block_luks_essiv_cipher(luks->cipher_alg, + luks->ivgen_hash_alg, + &local_err); + if (local_err) { + error_propagate(errp, local_err); + return -1; + } + } else { + + /* + * Note we parsed the ivhash_name earlier in the cipher_mode + * spec string even with plain/plain64 ivgens, but we + * will ignore it, since it is irrelevant for these ivgens. + * This is for compat with dm-crypt which will silently + * ignore hash names with these ivgens rather than report + * an error about the invalid usage + */ + luks->ivgen_cipher_alg = luks->cipher_alg; + } + return 0; +} + /* * Given a key slot, and user password, this will attempt to unlock * the master encryption key from the key slot. @@ -712,11 +835,8 @@ qcrypto_block_luks_open(QCryptoBlock *block, Error **errp) { QCryptoBlockLUKS *luks = NULL; - Error *local_err = NULL; g_autofree uint8_t *masterkey = NULL; - char *ivgen_name, *ivhash_name; g_autofree char *password = NULL; - g_autofree char *cipher_mode = NULL; if (!(flags & QCRYPTO_BLOCK_OPEN_NO_IO)) { if (!options->u.luks.key_secret) { @@ -738,107 +858,14 @@ qcrypto_block_luks_open(QCryptoBlock *block, goto fail; } - if (memcmp(luks->header.magic, qcrypto_block_luks_magic, - QCRYPTO_BLOCK_LUKS_MAGIC_LEN) != 0) { - error_setg(errp, "Volume is not in LUKS format"); - goto fail; - } - if (luks->header.version != QCRYPTO_BLOCK_LUKS_VERSION) { - error_setg(errp, "LUKS version %" PRIu32 " is not supported", - luks->header.version); - goto fail; - } - - cipher_mode = g_strdup(luks->header.cipher_mode); - - /* - * The cipher_mode header contains a string that we have - * to further parse, of the format - * - * -[:] - * - * eg cbc-essiv:sha256, cbc-plain64 - */ - ivgen_name = strchr(cipher_mode, '-'); - if (!ivgen_name) { - error_setg(errp, "Unexpected cipher mode string format %s", - cipher_mode); - goto fail; - } - *ivgen_name = '\0'; - ivgen_name++; - - ivhash_name = strchr(ivgen_name, ':'); - if (!ivhash_name) { - luks->ivgen_hash_alg = 0; - } else { - *ivhash_name = '\0'; - ivhash_name++; - - luks->ivgen_hash_alg = qcrypto_block_luks_hash_name_lookup(ivhash_name, - &local_err); - if (local_err) { - error_propagate(errp, local_err); - goto fail; - } - } - - luks->cipher_mode = qcrypto_block_luks_cipher_mode_lookup(cipher_mode, - &local_err); - if (local_err) { - error_propagate(errp, local_err); - goto fail; - } - - luks->cipher_alg = - qcrypto_block_luks_cipher_name_lookup(luks->header.cipher_name, - luks->cipher_mode, - luks->header.master_key_len, - &local_err); - if (local_err) { - error_propagate(errp, local_err); - goto fail; - } - - luks->hash_alg = - qcrypto_block_luks_hash_name_lookup(luks->header.hash_spec, - &local_err); - if (local_err) { - error_propagate(errp, local_err); + if (qcrypto_block_luks_check_header(luks, errp) < 0) { goto fail; } - luks->ivgen_alg = qcrypto_block_luks_ivgen_name_lookup(ivgen_name, - &local_err); - if (local_err) { - error_propagate(errp, local_err); + if (qcrypto_block_luks_parse_header(luks, errp) < 0) { goto fail; } - if (luks->ivgen_alg == QCRYPTO_IVGEN_ALG_ESSIV) { - if (!ivhash_name) { - error_setg(errp, "Missing IV generator hash specification"); - goto fail; - } - luks->ivgen_cipher_alg = - qcrypto_block_luks_essiv_cipher(luks->cipher_alg, - luks->ivgen_hash_alg, - &local_err); - if (local_err) { - error_propagate(errp, local_err); - goto fail; - } - } else { - /* Note we parsed the ivhash_name earlier in the cipher_mode - * spec string even with plain/plain64 ivgens, but we - * will ignore it, since it is irrelevant for these ivgens. - * This is for compat with dm-crypt which will silently - * ignore hash names with these ivgens rather than report - * an error about the invalid usage - */ - luks->ivgen_cipher_alg = luks->cipher_alg; - } - if (!(flags & QCRYPTO_BLOCK_OPEN_NO_IO)) { /* Try to find which key slot our password is valid for * and unlock the master key from that slot.