# We don't use a secret keyring, of course, but gpg panics and
# implodes if there isn't one available
-GPG_CMD="gpg --no-options --no-default-keyring --secret-keyring /etc/apt/secring.gpg --trustdb-name /etc/apt/trustdb.gpg"
+GPG_CMD="gpg --ignore-time-conflict --no-options --no-default-keyring --secret-keyring /etc/apt/secring.gpg --trustdb-name /etc/apt/trustdb.gpg"
GPG="$GPG_CMD --keyring /etc/apt/trusted.gpg"
+MASTER_KEYRING=""
+ARCHIVE_KEYRING_URI=""
+#MASTER_KEYRING=/usr/share/keyrings/debian-master-keyring.gpg
+#ARCHIVE_KEYRING_URI=http://ftp.debian.org/debian/debian-archive-keyring.gpg
+
ARCHIVE_KEYRING=/usr/share/keyrings/debian-archive-keyring.gpg
REMOVED_KEYS=/usr/share/keyrings/debian-archive-removed-keys.gpg
+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 $ADD_KEYRING --with-colons --list-keys | grep ^pub | cut -d: -f5`
+ master_keys=`$GPG_CMD --keyring $MASTER --with-colons --list-keys | grep ^pub | cut -d: -f5`
+ for add_key in $add_keys; do
+ ADDED=0
+ for master_key in $master_keys; do
+ if $GPG_CMD --keyring $ADD_KEYRING --list-sigs --with-colons $add_key | grep ^sig | cut -d: -f5 | grep -q $master_key; then
+ $GPG_CMD --quiet --batch --keyring $ADD_KEYRING --export $add_key | $GPG --import
+ 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
+}
+
+# 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() {
+ if [ -z "$ARCHIVE_KEYRING_URI" ]; then
+ echo "ERROR: no location for the archive-keyring given"
+ fi
+ if [ ! -d /var/lib/apt/keyrings ]; then
+ mkdir -p /var/lib/apt/keyrings
+ fi
+ keyring=/var/lib/apt/keyrings/$(basename $ARCHIVE_KEYRING)
+ old_mtime=0
+ if [ -e $keyring ]; then
+ old_mtime=$(stat -c %Y $keyring)
+ fi
+ (cd /var/lib/apt/keyrings; wget -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
exit 1
fi
- # add new keys
- $GPG_CMD --quiet --batch --keyring $ARCHIVE_KEYRING --export | $GPG --ignore-time-conflict --import
+ # 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 | $GPG --import
- # remove no-longer used keys
+ # remove no-longer supported/used keys
keys=`$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
done
}
+
usage() {
echo "Usage: apt-key [command] [arguments]"
echo
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
}
update)
update
;;
+ net-update)
+ net_update
+ ;;
list)
$GPG --batch --list-keys
;;