# -*-shell-script-*-
# This should be sourced by bash (though we welcome changes to make it POSIX sh compliant)

# Monkeysphere host revoke-key subcommand
#
# The monkeysphere scripts are written by:
# Jameson Rollins <jrollins@finestructure.net>
# Jamie McClelland <jm@mayfirst.org>
# Daniel Kahn Gillmor <dkg@fifthhorseman.net>
#
# They are Copyright 2008-2009, and are all released under the GPL,
# version 3 or later.

# revoke host key

revoke_key() {

# Coming in here, we expect $HOST_FINGERPRINT to be set, and we
# believe that there is in fact a key.

    if [ "$PROMPT" = "false" ] ; then
	publish=N
    else
	cat <<EOF >&2
This will generate a revocation certificate for your host key
(fingerprint: $HOST_FINGERPRINT) and
dump the certificate to standard output.

It can also directly publish the new revocation certificate
to the public keyservers via $KEYSERVER if you want it to.

Publishing this certificate will IMMEDIATELY and PERMANENTLY revoke
your host key!

EOF
	printf "Publish the certificate after generation? (y/n/Q) " >&2
	read publish
	
	if ! [ "${publish/y/Y}" = 'Y' -o "${publish/n/N}" = 'N' ] ; then
	    failure "aborting at user request"
	fi
    fi
    
    # our current implementation is very simple: we just want to
    # generate the revocation certificate on stdout.  This provides
    # for the two most likely (but hopefully not common) scenarios:

    # an admin wants a revocation certificate for the host which they
    # can store securely offline.  In this case, the admin can
    # redirect stdout to a file, or can simply copy/paste or
    # transcribe from the terminal.

    # Alternately, an admin might want to publish the revocation
    # certificate immediately, which we can help them do as well.

    if [ "$PROMPT" = 'false' ] ; then
	# FIXME: allow the end user to choose something other than
	# "key was compromised" (1) and to supply their own revocation
	# string.

	local revoke_commands="y
1
Monkeysphere host key revocation (automated) $(date '+%F_%T%z')

y

"
	revcert=$(GNUPGHOME="$GNUPGHOME_HOST" gpg_host --command-fd 0 --armor --gen-revoke "0x${HOST_FINGERPRINT}!" <<<"$revoke_commands" ) \
	    || failure "Failed to generate revocation certificate!"


    else
    # note: we're not using the gpg_host function because we actually
    # want to use gpg's UI in this case, so we want to omit --no-tty
	revcert=$(GNUPGHOME="$GNUPGHOME_HOST" gpg --no-greeting --quiet --armor --gen-revoke "0x${HOST_FINGERPRINT}!") \
	    || failure "Failed to generate revocation certificate!"
    fi

    # if you run gpg --gen-revoke but cancel it or quit in the middle,
    # it returns success, but emits no revocation certificate:
    if ! [ "$revcert" ] ; then
	failure "Revocation canceled."
    fi

    ## ok, now we have the revocation certificate.  Print it, and
    ## offer to publish if originally requested:
    printf "%s\n" "$revcert"

    if [ "${publish/y/Y}" = 'Y' ] ; then
	printf "\n" >&2
	printf "Really publish this cert to $KEYSERVER ? (Y/n) " >&2
	read really
	if [ "${really/n/N}" = 'N' ] ; then
	    printf "Not publishing.\n" >&2
	else
	    local newhome=$(mkmstempdir)
	    GNUPGHOME="$newhome" gpg --no-tty --quiet --import < "$HOST_KEY_FILE"
	    GNUPGHOME="$newhome" gpg --no-tty --quiet --import <<< "$revcert"
	    GNUPGHOME="$newhome" gpg --keyserver "$KEYSERVER" --send "0x${HOST_FINGERPRINT}!"
	    rm -rf "$newhome"
	fi
    fi
}