pacman/scripts/libmakepkg/source/git.sh.in
Eli Schwartz 39319c1860 libmakepkg: check for invalid tags in git
As per https://lists.archlinux.org/pipermail/arch-general/2017-July/043876.html
git doesn't check that the tag name matches what an annotated tag object
*thinks* it should be called. This is a bit of a theoretical attack and
some would argue that we should always use commits since upstream can
legitimately change a tag, but nevertheless this can result in a
downgrade attack if the git download transport was manipulated or the
upstream repository hacked.

So, check the tag blob to make sure the tag actually matches the name we
used for `git checkout`.

This really should be fixed in git itself, rather than forcing all
downstream users of git verify-tag to implement their own checks, but
the git developers disagree, see the discussion surrounding
https://public-inbox.org/git/xmqqk2hzldx8.fsf@gitster.mtv.corp.google.com/

Signed-off-by: Eli Schwartz <eschwartz@archlinux.org>
Signed-off-by: Allan McRae <allan@archlinux.org>
2017-09-13 14:20:35 +10:00

131 lines
3.7 KiB
Bash

#!/bin/bash
#
# git.sh - function for handling the download and "extraction" of Git sources
#
# Copyright (c) 2015-2017 Pacman Development Team <pacman-dev@archlinux.org>
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
#
[[ -n "$LIBMAKEPKG_SOURCE_GIT_SH" ]] && return
LIBMAKEPKG_SOURCE_GIT_SH=1
LIBRARY=${LIBRARY:-'@libmakepkgdir@'}
source "$LIBRARY/util/message.sh"
source "$LIBRARY/util/pkgbuild.sh"
download_git() {
local netfile=$1
local dir=$(get_filepath "$netfile")
[[ -z "$dir" ]] && dir="$SRCDEST/$(get_filename "$netfile")"
local repo=$(get_filename "$netfile")
local url=$(get_url "$netfile")
url=${url#git+}
url=${url%%#*}
url=${url%%\?*}
if [[ ! -d "$dir" ]] || dir_is_empty "$dir" ; then
msg2 "$(gettext "Cloning %s %s repo...")" "${repo}" "git"
if ! git clone --mirror "$url" "$dir"; then
error "$(gettext "Failure while downloading %s %s repo")" "${repo}" "git"
plain "$(gettext "Aborting...")"
exit 1
fi
elif (( ! HOLDVER )); then
cd_safe "$dir"
# Make sure we are fetching the right repo
if [[ "$url" != "$(git config --get remote.origin.url)" ]] ; then
error "$(gettext "%s is not a clone of %s")" "$dir" "$url"
plain "$(gettext "Aborting...")"
exit 1
fi
msg2 "$(gettext "Updating %s %s repo...")" "${repo}" "git"
if ! git fetch --all -p; then
# only warn on failure to allow offline builds
warning "$(gettext "Failure while updating %s %s repo")" "${repo}" "git"
fi
fi
}
extract_git() {
local netfile=$1 tagname
local fragment=$(get_uri_fragment "$netfile")
local repo=$(get_filename "$netfile")
local dir=$(get_filepath "$netfile")
[[ -z "$dir" ]] && dir="$SRCDEST/$(get_filename "$netfile")"
msg2 "$(gettext "Creating working copy of %s %s repo...")" "${repo}" "git"
pushd "$srcdir" &>/dev/null
local updating=0
if [[ -d "${dir##*/}" ]]; then
updating=1
cd_safe "${dir##*/}"
if ! git fetch; then
error "$(gettext "Failure while updating working copy of %s %s repo")" "${repo}" "git"
plain "$(gettext "Aborting...")"
exit 1
fi
cd_safe "$srcdir"
elif ! git clone "$dir" "${dir##*/}"; then
error "$(gettext "Failure while creating working copy of %s %s repo")" "${repo}" "git"
plain "$(gettext "Aborting...")"
exit 1
fi
cd_safe "${dir##*/}"
local ref=origin/HEAD
if [[ -n $fragment ]]; then
case ${fragment%%=*} in
commit|tag)
ref=${fragment##*=}
;;
branch)
ref=origin/${fragment##*=}
;;
*)
error "$(gettext "Unrecognized reference: %s")" "${fragment}"
plain "$(gettext "Aborting...")"
exit 1
esac
fi
if [[ ${fragment%%=*} = tag ]]; then
tagname="$(git tag -l --format='%(tag)' "$ref")"
if [[ -n $tagname && $tagname != $ref ]]; then
error "$(gettext "Failure while checking out version %s, the git tag has been forged")" "$ref"
plain "$(gettext "Aborting...")"
exit 1
fi
fi
if [[ $ref != "origin/HEAD" ]] || (( updating )) ; then
if ! git checkout --force --no-track -B makepkg $ref; then
error "$(gettext "Failure while creating working copy of %s %s repo")" "${repo}" "git"
plain "$(gettext "Aborting...")"
exit 1
fi
fi
popd &>/dev/null
}