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=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT 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 D3473C433E0 for ; Mon, 11 Jan 2021 04:00:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id ACAC72247F for ; Mon, 11 Jan 2021 04:00:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727191AbhAKEAM (ORCPT ); Sun, 10 Jan 2021 23:00:12 -0500 Received: from injection.crustytoothpaste.net ([192.241.140.119]:50720 "EHLO injection.crustytoothpaste.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726573AbhAKEAM (ORCPT ); Sun, 10 Jan 2021 23:00:12 -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 302846081F; Mon, 11 Jan 2021 03:58:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=crustytoothpaste.net; s=default; t=1610337531; 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=spcl1S+JUYJI4Ew3avp9eqhkA3vGkI4Lq+A0NaL9cStsw0WrTvsU8i8ejAtbfAy1r bR2W7mNki1pK6yHWdWQTCM4So769uAv7SJH6zViJVW8lkGcHZQM1/P7OWDMAZblfZf 1EKXOtUuvs98vLJsPRNJVLcb4uiBimnsTNj4CjPEGPqqcBVJE8UYvB0xj5T0jkJ2L7 S+L/MB17c5aGJrREE5XL6CsAFxknm8HUaPRHGprhNnAXrM+i7RpGftaKgCZE09bid/ IWHxE+DrsXNgdnLnzDNhwQp+pdgOD2O71ZK2Bfnnp8ACIJvaeczbfqBzlda7CkEsFO 4LWTpZQHDV8tMZWS1w83v85NSm+QAoS6SghBOlVveETUEPFEoQbyeWJ3Q0MzzRq/ME tZwksHggOkeg+PL29oLiIMRLStkFFSchhCMUW14dYorPmyH8p0r6lb7I2Z3wNcaiOP Zz4/Lkno0iA+8fJP3lG7dlBOPx2zM4SlerkKzM8CKLWve8j0tzN From: "brian m. carlson" To: Cc: Eric Sunshine , Denton Liu , Jeff King Subject: [PATCH v2 5/5] gpg-interface: remove other signature headers before verifying Date: Mon, 11 Jan 2021 03:58:40 +0000 Message-Id: <20210111035840.2437737-6-sandals@crustytoothpaste.net> X-Mailer: git-send-email 2.30.0.284.gd98b1dd5eaa7 In-Reply-To: <20210111035840.2437737-1-sandals@crustytoothpaste.net> References: <20210111003740.1319996-1-sandals@crustytoothpaste.net> <20210111035840.2437737-1-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)' \