apt/cmdline/apt-key

#!/bin/sh

set -e

# 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="$GPG_CMD --keyring /etc/apt/trusted.gpg"


ARCHIVE_KEYRING=/usr/share/keyrings/ubuntu-archive-keyring.gpg
REMOVED_KEYS=/usr/share/keyrings/ubuntu-archive-removed-keys.gpg


update() {
    if [ ! -f $ARCHIVE_KEYRING ]; then
	echo >&2 "ERROR: Can't find the archive-keyring"
	echo >&2 "Is the ubuntu-keyring package installed?"
	exit 1
    fi

    # add new keys
    $GPG_CMD --quiet --batch --keyring $ARCHIVE_KEYRING --export | $GPG --ignore-time-conflict --import

    # remove no-longer 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
}

usage() {
    echo "Usage: apt-key [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 list                - list keys"
    echo
}

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)
        $GPG --quiet --batch --import "$1"
        echo "OK"
        ;;
    del|rm|remove)
        $GPG --quiet --batch --delete-key --yes "$1"
        echo "OK"
        ;;
    update)
	update
	;;
    list)
        $GPG --batch --list-keys
        ;;
    finger*)
        $GPG --batch --fingerprint
        ;;
    export)
        $GPG --armor --export "$1"
        ;;
    exportall)
        $GPG --armor --export
        ;;
    adv*)
        echo "Executing: $GPG $*"
        $GPG $*
        ;;
    help)
        usage
        ;;
    *)
        usage
        exit 1
        ;;
esac