From nobody Wed Nov 12 10:06:14 2025 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com ARC-Seal: i=1; a=rsa-sha256; t=1569596534; cv=none; d=zoho.com; s=zohoarc; b=Urt3TG8Bj6+vUD1m2y93UmDPwqYLh/QyNjUgc5nfHuy1bzEiFfeG3JcugkgwNp68hKkD4qY8p3ykNaIf35a77s7MVgOoZN3AYMu8VNpoaHjS8wRuPgqeVaZ0pp0FdZmfnshYUKPA0yMW7lA31zjIXrCceCzULvupnivI8WjjWsY= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zoho.com; s=zohoarc; t=1569596534; h=Content-Type:Content-Transfer-Encoding:Cc:Date:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:To:ARC-Authentication-Results; bh=M3rOAZkOHKyzVsmdhuvxo5sCY7uVX7E5edeMX0LzL6U=; b=hytZj/ZT7FXdwBCMQHedHXzly14YIoZbTr7tLtnRHCIs10kKfcmlS29TFKHGwpzCutIa3xvF8fmH+/WCID+2fzBaD9scZ7X+x9w9vSRa7WrVUz2wSqvKZGV4SXn7NtkGHSH1ZQYsmBYRkse7CC9ij0CgcIxVD8BytcHZr9L01to= ARC-Authentication-Results: i=1; mx.zoho.com; spf=pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail header.from= (p=none dis=none) header.from= Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1569596534145469.3846014978242; Fri, 27 Sep 2019 08:02:14 -0700 (PDT) Received: from localhost ([::1]:52096 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iDrl5-000378-70 for importer@patchew.org; Fri, 27 Sep 2019 11:02:11 -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 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+importer=patchew.org@nongnu.org Sender: "Qemu-devel" Content-Type: text/plain; charset="utf-8" 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(QCryptoCipherAlgorithm= 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_STRIPES); =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_STRIP= ES; for (i =3D 0; i < QCRYPTO_BLOCK_LUKS_NUM_KEY_SLOTS; i++) { - luks->header.key_slots[i].active =3D QCRYPTO_BLOCK_LUKS_KEY_SLOT_D= ISABLED; - 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_SECTOR_= SIZE), - (QCRYPTO_BLOCK_LUKS_KEY_SLOT_OFFSET / - QCRYPTO_BLOCK_LUKS_SECTOR_SIZE)) * i); + slot->key_offset_sector =3D header_sectors + i * split_key_sectors; + 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_SIZE= ), - (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