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=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 2033BC388F4 for ; Fri, 27 Sep 2019 15:01:59 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id EEB6E2196E for ; Fri, 27 Sep 2019 15:01:58 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org EEB6E2196E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:52096 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iDrkr-000378-8Z for qemu-devel@archiver.kernel.org; Fri, 27 Sep 2019 11:01:57 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:37720) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iDqRX-0001Pf-Kv for qemu-devel@nongnu.org; Fri, 27 Sep 2019 09:37:56 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iDqRW-00039B-7B for qemu-devel@nongnu.org; Fri, 27 Sep 2019 09:37:55 -0400 Received: from mx1.redhat.com ([209.132.183.28]:58614) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1iDqRV-00038U-UF for qemu-devel@nongnu.org; Fri, 27 Sep 2019 09:37:54 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 60276898104 for ; Fri, 27 Sep 2019 09:59:47 +0000 (UTC) Received: from localhost.localdomain.com (ovpn-112-55.ams2.redhat.com [10.36.112.55]) by smtp.corp.redhat.com (Postfix) with ESMTP id 2464F60923; Fri, 27 Sep 2019 09:59:45 +0000 (UTC) From: =?UTF-8?q?Daniel=20P=2E=20Berrang=C3=A9?= To: qemu-devel@nongnu.org Subject: [PULL 10/11] qcrypto-luks: simplify the math used for keyslot locations Date: Fri, 27 Sep 2019 10:59:25 +0100 Message-Id: <20190927095926.22230-11-berrange@redhat.com> In-Reply-To: <20190927095926.22230-1-berrange@redhat.com> References: <20190927095926.22230-1-berrange@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.6.2 (mx1.redhat.com [10.5.110.67]); Fri, 27 Sep 2019 09:59:47 +0000 (UTC) Content-Transfer-Encoding: quoted-printable 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: =?UTF-8?q?Daniel=20P=2E=20Berrang=C3=A9?= , Maxim Levitsky Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" From: Maxim Levitsky Signed-off-by: Maxim Levitsky Reviewed-by: Daniel P. Berrang=C3=A9 Signed-off-by: Daniel P. Berrang=C3=A9 --- crypto/block-luks.c | 63 ++++++++++++++++++++++++++++----------------- 1 file changed, 40 insertions(+), 23 deletions(-) diff --git a/crypto/block-luks.c b/crypto/block-luks.c index 6d4e9eb348..a53d5d1916 100644 --- a/crypto/block-luks.c +++ b/crypto/block-luks.c @@ -409,6 +409,30 @@ qcrypto_block_luks_essiv_cipher(QCryptoCipherAlgorit= hm cipher, } } =20 +/* + * Returns number of sectors needed to store the key material + * given number of anti forensic stripes + */ +static int +qcrypto_block_luks_splitkeylen_sectors(const QCryptoBlockLUKS *luks, + unsigned int header_sectors, + unsigned int stripes) +{ + /* + * This calculation doesn't match that shown in the spec, + * but instead follows the cryptsetup implementation. + */ + + size_t splitkeylen =3D luks->header.master_key_len * stripes; + + /* First align the key material size to block size*/ + size_t splitkeylen_sectors =3D + DIV_ROUND_UP(splitkeylen, QCRYPTO_BLOCK_LUKS_SECTOR_SIZE); + + /* Then also align the key material size to the size of the header *= / + return ROUND_UP(splitkeylen_sectors, header_sectors); +} + /* * Stores the main LUKS header, taking care of endianess */ @@ -1114,7 +1138,8 @@ qcrypto_block_luks_create(QCryptoBlock *block, QCryptoBlockCreateOptionsLUKS luks_opts; Error *local_err =3D NULL; g_autofree uint8_t *masterkey =3D NULL; - size_t splitkeylen =3D 0; + size_t header_sectors; + size_t split_key_sectors; size_t i; g_autofree char *password =3D NULL; const char *cipher_alg; @@ -1333,37 +1358,29 @@ qcrypto_block_luks_create(QCryptoBlock *block, goto error; } =20 + /* start with the sector that follows the header*/ + header_sectors =3D QCRYPTO_BLOCK_LUKS_KEY_SLOT_OFFSET / + QCRYPTO_BLOCK_LUKS_SECTOR_SIZE; + + split_key_sectors =3D + qcrypto_block_luks_splitkeylen_sectors(luks, + header_sectors, + QCRYPTO_BLOCK_LUKS_STRIPE= S); =20 - /* Although LUKS has multiple key slots, we're just going - * to use the first key slot */ - splitkeylen =3D luks->header.master_key_len * QCRYPTO_BLOCK_LUKS_STR= IPES; for (i =3D 0; i < QCRYPTO_BLOCK_LUKS_NUM_KEY_SLOTS; i++) { - luks->header.key_slots[i].active =3D QCRYPTO_BLOCK_LUKS_KEY_SLOT= _DISABLED; - luks->header.key_slots[i].stripes =3D QCRYPTO_BLOCK_LUKS_STRIPES= ; + QCryptoBlockLUKSKeySlot *slot =3D &luks->header.key_slots[i]; + slot->active =3D QCRYPTO_BLOCK_LUKS_KEY_SLOT_DISABLED; =20 - /* This calculation doesn't match that shown in the spec, - * but instead follows the cryptsetup implementation. - */ - luks->header.key_slots[i].key_offset_sector =3D - (QCRYPTO_BLOCK_LUKS_KEY_SLOT_OFFSET / - QCRYPTO_BLOCK_LUKS_SECTOR_SIZE) + - (ROUND_UP(DIV_ROUND_UP(splitkeylen, QCRYPTO_BLOCK_LUKS_SECTO= R_SIZE), - (QCRYPTO_BLOCK_LUKS_KEY_SLOT_OFFSET / - QCRYPTO_BLOCK_LUKS_SECTOR_SIZE)) * i); + slot->key_offset_sector =3D header_sectors + i * split_key_secto= rs; + slot->stripes =3D QCRYPTO_BLOCK_LUKS_STRIPES; } =20 - /* The total size of the LUKS headers is the partition header + key * slot headers, rounded up to the nearest sector, combined with * the size of each master key material region, also rounded up * to the nearest sector */ - luks->header.payload_offset_sector =3D - (QCRYPTO_BLOCK_LUKS_KEY_SLOT_OFFSET / - QCRYPTO_BLOCK_LUKS_SECTOR_SIZE) + - (ROUND_UP(DIV_ROUND_UP(splitkeylen, QCRYPTO_BLOCK_LUKS_SECTOR_SI= ZE), - (QCRYPTO_BLOCK_LUKS_KEY_SLOT_OFFSET / - QCRYPTO_BLOCK_LUKS_SECTOR_SIZE)) * - QCRYPTO_BLOCK_LUKS_NUM_KEY_SLOTS); + luks->header.payload_offset_sector =3D header_sectors + + QCRYPTO_BLOCK_LUKS_NUM_KEY_SLOTS * split_key_sectors; =20 block->sector_size =3D QCRYPTO_BLOCK_LUKS_SECTOR_SIZE; block->payload_offset =3D luks->header.payload_offset_sector * --=20 2.21.0