From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on dcvr.yhbt.net X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=AWL,BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_PASS,SPF_PASS shortcircuit=no autolearn=ham autolearn_force=no version=3.4.2 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by dcvr.yhbt.net (Postfix) with ESMTP id 195941F934 for ; Mon, 11 Jan 2021 00:40:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727072AbhAKAjR (ORCPT ); Sun, 10 Jan 2021 19:39:17 -0500 Received: from injection.crustytoothpaste.net ([192.241.140.119]:50550 "EHLO injection.crustytoothpaste.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727049AbhAKAjQ (ORCPT ); Sun, 10 Jan 2021 19:39:16 -0500 Received: from camp.crustytoothpaste.net (unknown [IPv6:2001:470:b978:101:b610:a2f0:36c1:12e3]) (using TLSv1.2 with cipher ECDHE-RSA-CHACHA20-POLY1305 (256/256 bits)) (No client certificate requested) by injection.crustytoothpaste.net (Postfix) with ESMTPSA id 893186096B; Mon, 11 Jan 2021 00:37:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=crustytoothpaste.net; s=default; t=1610325476; bh=iOk2zNQtGOchx4/xFaRbXMeuwZfTKEgGvqnvKg8PJc0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From:Reply-To: Subject:Date:To:CC:Resent-Date:Resent-From:Resent-To:Resent-Cc: In-Reply-To:References:Content-Type:Content-Disposition; b=xYtP9vQBI6IhCRgmWHxs9WPpmfenO3XTXtmZh+2pZzQKt2pBeTeBkfIsh6Dp9todt YRIpSAkTUl711osHYEQntj7QOoSSs5Icf3heVdG0YkeCj71ex3t24+KnPoUno+aQWe LAO4RrPei9ktcU07VEHFqJJ97AqSUWdCXm3YIkU/+XPKRbvBXinlAefOqKGm7lK8UE 8vDR/JMkYuX2tgd0QeHSvVcFxCn4jhwuYfXxW+q6M3SBYee07dU9ATp+/DoSn4B9Ak NQPDs++l8tBIGtYL/RSjj1egmbGTUYfMJXaiZ8oadc3b55tmU+jVJP5OaIqh42Z0yF Yv62V6G5EAjR7LR9Ole9u4nW2LbqeEbbKz0Rrf+5hAk2OPSUv5V656vbBGa2QPMSug 4XU8r5SdMRakoskPYwwB/P3aLdfTgoJSEdqw6L+4b8VeVwj0dnNvqncNSfyHRvs5OO Nej4lY5a9Cthq+Rp2lruvQQlV26fNxRbTCpMoXKgozPhxOgXnG7 From: "brian m. carlson" To: Cc: Eric Sunshine , Denton Liu , Jeff King Subject: [PATCH 6/6] gpg-interface: remove other signature headers before verifying Date: Mon, 11 Jan 2021 00:37:40 +0000 Message-Id: <20210111003740.1319996-8-sandals@crustytoothpaste.net> X-Mailer: git-send-email 2.30.0.284.gd98b1dd5eaa7 In-Reply-To: <20210111003740.1319996-1-sandals@crustytoothpaste.net> References: <20210111003740.1319996-1-sandals@crustytoothpaste.net> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org When we have a multiply signed commit, we need to remove the signature in the header before verifying the object, since the trailing signature will not be over both pieces of data. Do so, and verify that we validate the signature appropriately. Signed-off-by: brian m. carlson --- gpg-interface.c | 2 ++ t/t7004-tag.sh | 25 +++++++++++++++++++++++++ 2 files changed, 27 insertions(+) diff --git a/gpg-interface.c b/gpg-interface.c index c6274c14af..127aecfc2b 100644 --- a/gpg-interface.c +++ b/gpg-interface.c @@ -1,4 +1,5 @@ #include "cache.h" +#include "commit.h" #include "config.h" #include "run-command.h" #include "strbuf.h" @@ -366,6 +367,7 @@ int parse_signature(const char *buf, size_t size, struct strbuf *payload, struct size_t match = parse_signed_buffer(buf, size); if (match != size) { strbuf_add(payload, buf, match); + remove_signature(payload); strbuf_add(signature, buf + match, size - match); return 1; } diff --git a/t/t7004-tag.sh b/t/t7004-tag.sh index 05f411c821..6fb4e3cf11 100755 --- a/t/t7004-tag.sh +++ b/t/t7004-tag.sh @@ -17,6 +17,13 @@ tag_exists () { git show-ref --quiet --verify refs/tags/"$1" } +test_expect_success 'setup' ' + test_oid_cache <<-EOM + othersigheader sha1:gpgsig-sha256 + othersigheader sha256:gpgsig + EOM +' + test_expect_success 'listing all tags in an empty tree should succeed' ' git tag -l && git tag @@ -1371,6 +1378,24 @@ test_expect_success GPG \ 'test_config gpg.program echo && test_must_fail git tag -s -m tail tag-gpg-failure' +# try to produce invalid signature +test_expect_success GPG 'git verifies tag is valid with double signature' ' + git tag -s -m tail tag-gpg-double-sig && + git cat-file tag tag-gpg-double-sig >tag && + othersigheader=$(test_oid othersigheader) && + sed -ne "/^\$/q;p" tag >new-tag && + cat <<-EOM >>new-tag && + $othersigheader -----BEGIN PGP SIGNATURE----- + someinvaliddata + -----END PGP SIGNATURE----- + EOM + sed -e "1,/^tagger/d" tag >>new-tag && + new_tag=$(git hash-object -t tag -w new-tag) && + git update-ref refs/tags/tag-gpg-double-sig $new_tag && + git verify-tag tag-gpg-double-sig && + git fsck +' + # try to sign with bad user.signingkey test_expect_success GPGSM \ 'git tag -s fails if gpgsm is misconfigured (bad key)' \