#!/bin/sh set -e unset GREP_OPTIONS GPG_CMD="gpg --ignore-time-conflict --no-options --no-default-keyring" # gpg needs a trustdb to function, but it can't be invalid (not even empty) # so we create a temporary directory to store our fresh readable trustdb in TRUSTDBDIR="$(mktemp -d)" CURRENTTRAP="${CURRENTTRAP} rm -rf '${TRUSTDBDIR}';" trap "${CURRENTTRAP}" 0 HUP INT QUIT ILL ABRT FPE SEGV PIPE TERM chmod 700 "$TRUSTDBDIR" # We also don't use a secret keyring, of course, but gpg panics and # implodes if there isn't one available - and writeable for imports SECRETKEYRING="${TRUSTDBDIR}/secring.gpg" touch $SECRETKEYRING GPG_CMD="$GPG_CMD --secret-keyring $SECRETKEYRING" GPG_CMD="$GPG_CMD --trustdb-name ${TRUSTDBDIR}/trustdb.gpg" # now create the trustdb with an (empty) dummy keyring $GPG_CMD --quiet --check-trustdb --keyring $SECRETKEYRING # and make sure that gpg isn't trying to update the file GPG_CMD="$GPG_CMD --no-auto-check-trustdb --trust-model always" GPG="$GPG_CMD" MASTER_KEYRING='&keyring-master-filename;' eval $(apt-config shell MASTER_KEYRING APT::Key::MasterKeyring) ARCHIVE_KEYRING='&keyring-filename;' eval $(apt-config shell ARCHIVE_KEYRING APT::Key::ArchiveKeyring) REMOVED_KEYS='&keyring-removed-filename;' eval $(apt-config shell REMOVED_KEYS APT::Key::RemovedKeys) ARCHIVE_KEYRING_URI='&keyring-uri;' eval $(apt-config shell ARCHIVE_KEYRING_URI APT::Key::ArchiveKeyringURI) TMP_KEYRING=/var/lib/apt/keyrings/maybe-import-keyring.gpg requires_root() { if [ "$(id -u)" -ne 0 ]; then echo >&1 "ERROR: This command can only be used by root." exit 1 fi } # gpg defaults to mode 0600 for new keyrings. Create one with 0644 instead. init_keyring() { for path; do if ! [ -e "$path" ]; then touch -- "$path" chmod 0644 -- "$path" fi done } add_keys_with_verify_against_master_keyring() { ADD_KEYRING=$1 MASTER=$2 if [ ! -f "$ADD_KEYRING" ]; then echo "ERROR: '$ADD_KEYRING' not found" return fi if [ ! -f "$MASTER" ]; then echo "ERROR: '$MASTER' not found" return fi # when adding new keys, make sure that the archive-master-keyring # is honored. so: # all keys that are exported must have a valid signature # from a key in the $distro-master-keyring add_keys=`$GPG_CMD --keyring $ADD_KEYRING --with-colons --list-keys | grep ^pub | cut -d: -f5` all_add_keys=`$GPG_CMD --keyring $ADD_KEYRING --with-colons --list-keys | grep ^[ps]ub | cut -d: -f5` master_keys=`$GPG_CMD --keyring $MASTER --with-colons --list-keys | grep ^pub | cut -d: -f5` # ensure there are no colisions LP: #857472 for all_add_key in $all_add_keys; do for master_key in $master_keys; do if [ "$all_add_key" = "$master_key" ]; then echo >&2 "Keyid collision for '$all_add_key' detected, operation aborted" return 1 fi done done for add_key in $add_keys; do # export the add keyring one-by-one rm -f $TMP_KEYRING $GPG_CMD --keyring $ADD_KEYRING --output $TMP_KEYRING --export $add_key # check if signed with the master key and only add in this case ADDED=0 for master_key in $master_keys; do if $GPG_CMD --keyring $MASTER --keyring $TMP_KEYRING --check-sigs --with-colons $add_key | grep '^sig:!:' | cut -d: -f5 | grep -q $master_key; then $GPG --import $TMP_KEYRING ADDED=1 fi done if [ $ADDED = 0 ]; then echo >&2 "Key '$add_key' not added. It is not signed with a master key" fi done rm -f $TMP_KEYRING } # update the current archive signing keyring from a network URI # the archive-keyring keys needs to be signed with the master key # (otherwise it does not make sense from a security POV) net_update() { # Disabled for now as code is insecure (LP: #1013639 (and 857472, 1013128)) exit 1 if [ -z "$ARCHIVE_KEYRING_URI" ]; then echo >&2 "ERROR: Your distribution is not supported in net-update as no uri for the archive-keyring is set" exit 1 fi requires_root # in theory we would need to depend on wget for this, but this feature # isn't useable in debian anyway as we have no keyring uri nor a master key if ! which wget >/dev/null 2>&1; then echo >&2 "ERROR: an installed wget is required for a network-based update" exit 1 fi if [ ! -d /var/lib/apt/keyrings ]; then mkdir -p /var/lib/apt/keyrings fi keyring=/var/lib/apt/keyrings/$(basename $ARCHIVE_KEYRING) old_mtime=0 if [ -e $keyring ]; then old_mtime=$(stat -c %Y $keyring) fi (cd /var/lib/apt/keyrings; wget --timeout=90 -q -N $ARCHIVE_KEYRING_URI) if [ ! -e $keyring ]; then return fi new_mtime=$(stat -c %Y $keyring) if [ $new_mtime -ne $old_mtime ]; then echo "Checking for new archive signing keys now" add_keys_with_verify_against_master_keyring $keyring $MASTER_KEYRING fi } update() { if [ ! -f $ARCHIVE_KEYRING ]; then echo >&2 "ERROR: Can't find the archive-keyring" echo >&2 "Is the &keyring-package; package installed?" exit 1 fi requires_root # add new keys from the package; # we do not use add_keys_with_verify_against_master_keyring here, # because "update" is run on regular package updates. A # attacker might as well replace the master-archive-keyring file # in the package and add his own keys. so this check wouldn't # add any security. we *need* this check on net-update though $GPG_CMD --quiet --batch --keyring $ARCHIVE_KEYRING --export | $GPG --import if [ -r "$REMOVED_KEYS" ]; then # remove no-longer supported/used keys keys=`$GPG_CMD --keyring $REMOVED_KEYS --with-colons --list-keys | grep ^pub | cut -d: -f5` for key in $keys; do if $GPG --list-keys --with-colons | grep ^pub | cut -d: -f5 | grep -q $key; then $GPG --quiet --batch --delete-key --yes ${key} fi done else echo "Warning: removed keys keyring $REMOVED_KEYS missing or not readable" >&2 fi } remove_key_from_keyring() { local GPG="$GPG_CMD --keyring $1" # check if the key is in this keyring: the key id is in the 5 column at the end if ! $GPG --with-colons --list-keys 2>&1 | grep -q "^pub:[^:]*:[^:]*:[^:]*:[0-9A-F]\+$2:"; then return fi if [ ! -w "$1" ]; then echo >&2 "Key ${2} is in keyring ${1}, but can't be removed as it is read only." return fi # check if it is the only key in the keyring and if so remove the keyring alltogether if [ '1' = "$($GPG --with-colons --list-keys | grep "^pub:[^:]*:[^:]*:[^:]*:[0-9A-F]\+:" | wc -l)" ]; then mv -f "$1" "${1}~" # behave like gpg return fi # we can't just modify pointed to files as these might be in /usr or something local REALTARGET if [ -L "$1" ]; then REALTARGET="$(readlink -f "$1")" mv -f "$1" "${1}.dpkg-tmp" cp -a "$REALTARGET" "$1" ls "$(dirname $1)" fi # delete the key from the keyring $GPG --batch --delete-key --yes "$2" if [ -n "$REALTARGET" ]; then # the real backup is the old link, not the copy we made mv -f "${1}.dpkg-tmp" "${1}~" fi } remove_key() { requires_root # if a --keyring was given, just remove from there if [ -n "$FORCED_KEYRING" ]; then remove_key_from_keyring "$FORCED_KEYRING" "$1" else # otherwise all known keyrings are up for inspection local TRUSTEDFILE="/etc/apt/trusted.gpg" eval $(apt-config shell TRUSTEDFILE Apt::GPGV::TrustedKeyring) eval $(apt-config shell TRUSTEDFILE Dir::Etc::Trusted/f) remove_key_from_keyring "$TRUSTEDFILE" "$1" TRUSTEDPARTS="/etc/apt/trusted.gpg.d" eval $(apt-config shell TRUSTEDPARTS Dir::Etc::TrustedParts/d) if [ -d "$TRUSTEDPARTS" ]; then for trusted in $(run-parts --list "$TRUSTEDPARTS" --regex '^.*\.gpg$'); do remove_key_from_keyring "$trusted" "$1" done fi fi echo "OK" } usage() { echo "Usage: apt-key [--keyring file] [command] [arguments]" echo echo "Manage apt's list of trusted keys" echo echo " apt-key add <file> - add the key contained in <file> ('-' for stdin)" echo " apt-key del <keyid> - remove the key <keyid>" echo " apt-key export <keyid> - output the key <keyid>" echo " apt-key exportall - output all trusted keys" echo " apt-key update - update keys using the keyring package" echo " apt-key net-update - update keys using the network" echo " apt-key list - list keys" echo " apt-key finger - list fingerprints" echo " apt-key adv - pass advanced options to gpg (download key)" echo echo "If no specific keyring file is given the command applies to all keyring files." } while [ -n "$1" ]; do case "$1" in --keyring) shift TRUSTEDFILE="$1" FORCED_KEYRING="$1" if [ -r "$TRUSTEDFILE" ] || [ "$2" = 'add' ] || [ "$2" = 'adv' ]; then GPG="$GPG --keyring $TRUSTEDFILE --primary-keyring $TRUSTEDFILE" else echo >&2 "Error: The specified keyring »$TRUSTEDFILE« is missing or not readable" exit 1 fi shift ;; --fakeroot) requires_root() { true; } shift ;; --*) echo >&2 "Unknown option: $1" usage exit 1;; *) break;; esac done if [ -z "$TRUSTEDFILE" ]; then TRUSTEDFILE="/etc/apt/trusted.gpg" eval $(apt-config shell TRUSTEDFILE Apt::GPGV::TrustedKeyring) eval $(apt-config shell TRUSTEDFILE Dir::Etc::Trusted/f) if [ -r "$TRUSTEDFILE" ]; then GPG="$GPG --keyring $TRUSTEDFILE" fi GPG="$GPG --primary-keyring $TRUSTEDFILE" TRUSTEDPARTS="/etc/apt/trusted.gpg.d" eval $(apt-config shell TRUSTEDPARTS Dir::Etc::TrustedParts/d) if [ -d "$TRUSTEDPARTS" ]; then # strip / suffix as gpg will double-slash in that case (#665411) STRIPPED_TRUSTEDPARTS="${TRUSTEDPARTS%/}" if [ "${STRIPPED_TRUSTEDPARTS}/" = "$TRUSTEDPARTS" ]; then TRUSTEDPARTS="$STRIPPED_TRUSTEDPARTS" fi for trusted in $(run-parts --list "$TRUSTEDPARTS" --regex '^.*\.gpg$'); do GPG="$GPG --keyring $trusted" done fi fi command="$1" if [ -z "$command" ]; then usage exit 1 fi shift if [ "$command" != "help" ] && ! which gpg >/dev/null 2>&1; then echo >&2 "Warning: gnupg does not seem to be installed." echo >&2 "Warning: apt-key requires gnupg for most operations." echo >&2 fi case "$command" in add) requires_root init_keyring "$TRUSTEDFILE" $GPG --quiet --batch --import "$1" echo "OK" ;; del|rm|remove) init_keyring "$TRUSTEDFILE" remove_key "$1" ;; update) init_keyring "$TRUSTEDFILE" update ;; net-update) init_keyring "$TRUSTEDFILE" net_update ;; list) init_keyring "$TRUSTEDFILE" $GPG --batch --list-keys ;; finger*) init_keyring "$TRUSTEDFILE" $GPG --batch --fingerprint ;; export) init_keyring "$TRUSTEDFILE" $GPG --armor --export "$1" ;; exportall) init_keyring "$TRUSTEDFILE" $GPG --armor --export ;; adv*) init_keyring "$TRUSTEDFILE" echo "Executing: $GPG $*" $GPG $* ;; help) usage ;; *) usage exit 1 ;; esac