#!/bin/ksh93
#
# CDDL HEADER START
#
# The contents of this file are subject to the terms of the
# Common Development and Distribution License (the "License").
# You may not use this file except in compliance with the License.
#
# You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
# or http://www.opensolaris.org/os/licensing.
# See the License for the specific language governing permissions
# and limitations under the License.
#
# When distributing Covered Code, include this CDDL HEADER in each
# file and include the License file at usr/src/OPENSOLARIS.LICENSE.
# If applicable, add the following below this CDDL HEADER, with the
# fields enclosed by brackets "[]" replaced with your own identifying
# information: Portions Copyright [yyyy] [name of copyright owner]
#
# CDDL HEADER END
#

#
# Copyright (c) 2011, 2016, Oracle and/or its affiliates. All rights reserved.
# Portions Copyright (c) 2016, Jens Elkner.

. /lib/svc/share/smf_include.sh
. /lib/svc/share/net_include.sh

SVCPROP='/usr/bin/svcprop'
CHMOD='/usr/bin/chmod'
CHOWN='/usr/bin/chown'
TOUCH='/usr/bin/touch'
ID='/usr/bin/id'

DHCPD_IPV4='svc:/network/dhcp/server:ipv4'
DHCPD_IPV6='svc:/network/dhcp/server:ipv6'
DHCPRELAY_IPV4='svc:/network/dhcp/relay:ipv4'
DHCPRELAY_IPV6='svc:/network/dhcp/relay:ipv6'

DHCPD_BIN='@CLIENT_BASEDIR@/lib/inet/dhcpd'
DHCPRELAY_BIN='@CLIENT_BASEDIR@/lib/inet/dhcrelay'

#
# dhcpd/dhcprelay can run in a global or exclusive-stack zone only
#
smf_configure_ip || exit ${SMF_EXIT_OK}

if [[ -z ${SMF_FMRI} ]]; then
	print -u2 'SMF framework variables are not initialized.'
	exit ${SMF_EXIT_ERR}
fi

#
# get_prop fmri propname
#
function get_prop {
	VALUE=${ ${SVCPROP} -cp config/$1 ${SMF_FMRI} 2>/dev/null ; }
	# Empty astring_list values show up as "" - do not return this.
	[[ ${VALUE} != '""' ]] && print -- "${VALUE}"
}

function errlog {
	print -u2 -- "$@"
}

function get_common_options {
	# get debug property value 
	typeset DEBUG='-q'
	[[ ${ get_prop debug ; } == 'true' ]] && DEBUG='-d'

	OPTS+=( ${DEBUG} )
}

#
# expand_prop "prop_name" "var_name" [ argflag ]
#
#     prop_name		FMRI property name
#     var_name		variable where result is stored; initialized to ""
#     argflag		The flag to be prepended to each property
#			value; optional argument
#
# This function will retrieve the properties for "prop_name" via a call
# to get_prop(). It will split-up the property values; it assumes that
# the delimiter is whitespace. It will then prepend "argflag" to each
# property value. The results will be stored in "var_name" which is
# passed by reference.
#
# Return values:
#
#     0			Success
#     1			Failure
#
function expand_prop {
	if (( $# < 2 )) || [[ -z $2 ]]; then
		errlog 'Internal error - expand_prop() has incorrect arguments'
		return 1
	fi

	typeset prop_name="$1" argflag="$3"
	typeset -n var_name="$2"

	typeset prop_values=( ${ get_prop ${prop_name} ; } )
	if [[  -z ${prop_values} ]]; then
		errlog "The property, '${prop_name}', is empty"
		return 1
	fi

	var_name=
	for item in "${prop_values[@]}" ; do
		var_name+=" ${argflag} ${item}"
	done

	return 0
}


function get_dhcpd_options {
	# get listen_ifname property value.
	typeset LISTENIFNAMES=${ get_prop listen_ifnames ; }

	#
	# get common config file properties
	#
	typeset CONFIGFILE=${ get_prop config_file ; }
	if [[ -z ${CONFIGFILE} ]]; then
		errlog 'No config_file specified, exiting'
		return 1
	fi
	if [[ ! -f ${CONFIGFILE} ]]; then
		errlog "Required config_file '${CONFIGFILE}' not found, exiting"
		return 1
	fi

	#
	# If a leasefile does not exist, create an empty file.
	#
	typeset LEASEFILE=${ get_prop lease_file ; }
	if [[ -z ${LEASEFILE} ]]; then
		errlog 'No lease_file specified, exiting'
		return 1
	fi

	typeset LEASEFILE_PERMS='u=rw,go=r'
	if [[ ! -f ${LEASEFILE} ]]; then
		${TOUCH} ${LEASEFILE}
		${CHMOD} ${LEASEFILE_PERMS} ${LEASEFILE}
	fi
	if [[ ! -w ${LEASEFILE} ]]; then
		errlog "Lease file '${LEASEFILE}' is not writable. You should:"
		errlog ${CHOWN} ${ ${ID} -u -n ; } "${LEASEFILE}"
		errlog ${CHMOD} ${LEASEFILE_PERMS} "${LEASEFILE}"
		return 1
	fi

	OPTS+=( '-cf' "${CONFIGFILE}" '-lf' "${LEASEFILE}" ${LISTENIFNAMES} )
}

function get_dhcprelay_options_v4 {
	#
	# Get append_agent_option V4 property value 
	#
	typeset APPEND=
	[[ ${ get_prop append_agent_option ; } == 'true' ]] && APPEND='-a -m append'

	#
	# get listen_ifname property value and modify it.  
	# If listen_ifnames property value is "e1000g01 iprb0" then the
	# command line option will look like  "-i e1000g0 -i iprb0"
	#
	typeset IIFLIST=
	expand_prop listen_ifnames IIFLIST -i || return $?

	#
	# Get servers  V4 property value - command line option will look
	# like  "1.2.3.5" "4.5.6.7".
	#
	# NOTE: By default server property value is empty. User must
	# first specify a server using svccfg/setprop command
	# before enabling service.
	#
	typeset DHCPSERVERS=${ get_prop servers ; }
	if [[  -z ${DHCPSERVERS} ]]; then
		errlog 'Must specify at least one "servers" property value, exiting'
		return 1
	fi

	OPTS+=( '-4' ${APPEND} ${IIFLIST} ${DHCPSERVERS} )
}

function get_dhcprelay_options_v6 {
	#
	# Get receivelinks  V6 property value and modify it:
	# Given property values of "1.2.3.4%bge0#1 bge2,1.2.3.4%iprb",
	# the command line option will look like  "-l 1.2.3.4%bge0#1 -l
	# bge2 -l 1.2.3.4%iprb".
	#
	# NOTE: By default receivelinks value is empty. User must
	# first specify a server using svccfg/setprop command
	# before enabling service.
	#
	typeset IRECVLINKS=
	expand_prop receive_query_links IRECVLINKS -l || return $?
	#
	# Get forwardlinks V6 property value and modify it:
	# Given forward_query_links property value is "1.2.3.4%bge0 bge2,"
	# then the command line option will look like  "-u 1.2.3.4%bge0 -u
	# bge2"
	#
	# NOTE: By default forwardlinks value is empty. User must
	# first specify a server using svccfg/setprop command
	# before enabling service.
	#
	typeset IFWDLINKS=
	expand_prop forward_query_links IFWDLINKS -u || return $?

	OPTS+=( '-6' ${IRECVLINKS} ${IFWDLINKS} )
}

# actually this is the default per compile option
OPTS=( '--no-pid' )

case "${SMF_FMRI}" in
"${DHCPD_IPV4}"|"${DHCPD_IPV6}")
	# get omapi_conn_limit property value.
	export OMAPI_CONN_LIMIT=${ get_prop omapi_conn_limit ; }

	[[ ${SMF_FMRI} == ${DHCPD_IPV4} ]] && OPTS+=( '-4' ) || OPTS+=( '-6' )
	get_common_options || exit ${SMF_EXIT_ERR_CONFIG}
	get_dhcpd_options || exit ${SMF_EXIT_ERR_CONFIG}
	EXECFILE=${DHCPD_BIN}
	;;

"${DHCPRELAY_IPV4}")
	get_common_options || exit ${SMF_EXIT_ERR_CONFIG}
	get_dhcprelay_options_v4 || exit ${SMF_EXIT_ERR_CONFIG}
	EXECFILE=${DHCPRELAY_BIN}
	;;

"${DHCPRELAY_IPV6}")
	get_common_options || exit ${SMF_EXIT_ERR_CONFIG}
	get_dhcprelay_options_v6 || exit ${SMF_EXIT_ERR_CONFIG}
	EXECFILE=${DHCPRELAY_BIN}
	;;

*)
	print -u2 'isc-dhcp must be invoked from within SMF'
	exit ${SMF_EXIT_ERR_FATAL}
	;;

esac

# Now start the daemon
if [[ ${DEBUG} == '-d' ]]; then
	${EXECFILE} "${OPTS[@]}" &
else
	${EXECFILE} "${OPTS[@]}"
fi

(( $? )) && exit ${SMF_EXIT_ERR_FATAL} || exit ${SMF_EXIT_OK}