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Diffstat (limited to 'cmdline/apt-key.in')
| -rw-r--r-- | cmdline/apt-key.in | 362 |
1 files changed, 362 insertions, 0 deletions
diff --git a/cmdline/apt-key.in b/cmdline/apt-key.in new file mode 100644 index 000000000..0774cf4b7 --- /dev/null +++ b/cmdline/apt-key.in @@ -0,0 +1,362 @@ +#!/bin/sh + +set -e +unset GREP_OPTIONS + +GPG_CMD="gpg --ignore-time-conflict --no-options --no-default-keyring" + +# gpg needs (in different versions more or less) files to function correctly, +# so we give it its own homedir and generate some valid content for it +GPGHOMEDIR="$(mktemp -d)" +CURRENTTRAP="${CURRENTTRAP} rm -rf '${GPGHOMEDIR}';" +trap "${CURRENTTRAP}" 0 HUP INT QUIT ILL ABRT FPE SEGV PIPE TERM +chmod 700 "$GPGHOMEDIR" +# We don't use a secret keyring, of course, but gpg panics and +# implodes if there isn't one available - and writeable for imports +SECRETKEYRING="${GPGHOMEDIR}/secring.gpg" +touch $SECRETKEYRING +GPG_CMD="$GPG_CMD --homedir $GPGHOMEDIR" +# create the trustdb with an (empty) dummy keyring +# older gpgs required it, newer gpgs even warn that it isn't needed, +# but require it nonetheless for some commands, so we just play safe +# here for the foreseeable future and create a dummy one +$GPG_CMD --quiet --check-trustdb --keyring $SECRETKEYRING >/dev/null 2>&1 +# tell gpg that it shouldn't try to maintain a trustdb file +GPG_CMD="$GPG_CMD --no-auto-check-trustdb --trust-model always" + +GPG="$GPG_CMD" + +APT_DIR="/" +eval $(apt-config shell APT_DIR Dir) + +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 $(apt-config shell ARCHIVE_KEYRING_URI APT::Key::ArchiveKeyringURI) +TMP_KEYRING=${APT_DIR}/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)) + APT_KEY_NET_UPDATE_ENABLED="" + eval $(apt-config shell APT_KEY_NET_UPDATE_ENABLED APT::Key::Net-Update-Enabled) + if [ -z "$APT_KEY_NET_UPDATE_ENABLED" ]; then + exit 1 + fi + + 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 ${APT_DIR}/var/lib/apt/keyrings ]; then + mkdir -p ${APT_DIR}/var/lib/apt/keyrings + fi + keyring=${APT_DIR}/var/lib/apt/keyrings/$(basename $ARCHIVE_KEYRING_URI) + old_mtime=0 + if [ -e $keyring ]; then + old_mtime=$(stat -c %Y $keyring) + fi + (cd ${APT_DIR}/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 ${1}, but can't be removed as it is read only." + return + fi + # check if it is the only key in the keyring and if so remove the keyring altogether + if [ '1' = "$($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 |