jail

#!/bin/sh
#
# $FreeBSD$
#

# PROVIDE: jail
# REQUIRE: LOGIN cleanvar
# BEFORE: securelevel
# KEYWORD: nojail shutdown

. /etc/rc.subr

name="jail"
rcvar=`set_rcvar`
start_cmd="jail_start"
stop_cmd="jail_stop"

# init_variables _j
#	Initialize the various jail variables for jail _j.
#
init_variables()
{
	_j="$1"

	if [ -z "$_j" ]; then
		warn "init_variables: you must specify a jail"
		return
	fi

	eval jail_rootdir=\"\$jail_${_j}_rootdir\"
	jail_devdir="${jail_rootdir}/dev"
	jail_fdescdir="${jail_devdir}/fd"
	jail_procdir="${jail_rootdir}/proc"
	eval jail_hostname=\"\$jail_${_j}_hostname\"
	eval jail_ip=\"\$jail_${_j}_ip\"
	eval jail_interface=\"\${jail_${_j}_interface:-${jail_interface}}\"
	eval jail_exec=\"\$jail_${_j}_exec\"
	eval jail_exec_start=\"\${jail_${_j}_exec_start:-${jail_exec_start}}\"
	eval jail_exec_stop=\"\${jail_${_j}_exec_stop:-${jail_exec_stop}}\"
	if [ -n "${jail_exec}" ]; then
		#   simple/backward-compatible execution
		jail_exec_start="${jail_exec}"
		jail_exec_stop=""
	else
		#   flexible execution
		if [ -z "${jail_exec_start}" ]; then
			jail_exec_start="/bin/sh /etc/rc"
			if [ -z "${jail_exec_stop}" ]; then
				jail_exec_stop="/bin/sh /etc/rc.shutdown"
			fi
		fi
	fi

	# The default jail ruleset will be used by rc.subr if none is specified.
	eval jail_ruleset=\"\${jail_${_j}_devfs_ruleset:-${jail_devfs_ruleset}}\"
	eval jail_devfs=\"\${jail_${_j}_devfs_enable:-${jail_devfs_enable}}\"
	[ -z "${jail_devfs}" ] && jail_devfs="NO"
	eval jail_fdescfs=\"\${jail_${_j}_fdescfs_enable:-${jail_fdescfs_enable}}\"
	[ -z "${jail_fdescfs}" ] && jail_fdescfs="NO"
	eval jail_procfs=\"\${jail_${_j}_procfs_enable:-${jail_procfs_enable}}\"
	[ -z "${jail_procfs}" ] && jail_procfs="NO"

	eval jail_mount=\"\${jail_${_j}_mount_enable:-${jail_mount_enable}}\"
	[ -z "${jail_mount}" ] && jail_mount="NO"
	# "/etc/fstab.${_j}" will be used for {,u}mount(8) if none is specified.
	eval jail_fstab=\"\${jail_${_j}_fstab:-${jail_fstab}}\"
	[ -z "${jail_fstab}" ] && jail_fstab="/etc/fstab.${_j}"
	eval jail_flags=\"\${jail_${_j}_flags:-${jail_flags}}\"
	[ -z "${jail_flags}" ] && jail_flags="-l -U root"

	# Debugging aid
	#
	debug "$_j devfs enable: $jail_devfs"
	debug "$_j fdescfs enable: $jail_fdescfs"
	debug "$_j procfs enable: $jail_procfs"
	debug "$_j mount enable: $jail_mount"
	debug "$_j hostname: $jail_hostname"
	debug "$_j ip: $jail_ip"
	debug "$_j interface: $jail_interface"
	debug "$_j root: $jail_rootdir"
	debug "$_j devdir: $jail_devdir"
	debug "$_j fdescdir: $jail_fdescdir"
	debug "$_j procdir: $jail_procdir"
	debug "$_j ruleset: $jail_ruleset"
	debug "$_j fstab: $jail_fstab"
	debug "$_j exec start: $jail_exec_start"
	debug "$_j exec stop: $jail_exec_stop"
	debug "$_j flags: $jail_flags"
}

# set_sysctl rc_knob mib msg
#	If the mib sysctl is set according to what rc_knob
#	specifies, this function does nothing. However if
#	rc_knob is set differently than mib, then the mib
#	is set accordingly and msg is displayed followed by
#	an '=" sign and the word 'YES' or 'NO'.
#
set_sysctl()
{
	_knob="$1"
	_mib="$2"
	_msg="$3"

	_current=`${SYSCTL} -n $_mib 2>/dev/null`
	if checkyesno $_knob ; then
		if [ "$_current" -ne 1 ]; then
			echo -n " ${_msg}=YES"
			${SYSCTL_W} 1>/dev/null ${_mib}=1
		fi
	else
		if [ "$_current" -ne 0 ]; then
			echo -n " ${_msg}=NO"
			${SYSCTL_W} 1>/dev/null ${_mib}=0
		fi
	fi
}

# jail_umount_fs
#	This function unmounts certain special filesystems in the
#	currently selected jail. The caller must call the init_variables()
#	routine before calling this one.
#
jail_umount_fs()
{
	if checkyesno jail_fdescfs; then
		if [ -d "${jail_fdescdir}" ] ; then
			umount -f ${jail_fdescdir} >/dev/null 2>&1
		fi
	fi
	if checkyesno jail_devfs; then
		if [ -d "${jail_devdir}" ] ; then
			umount -f ${jail_devdir} >/dev/null 2>&1
		fi
	fi
	if checkyesno jail_procfs; then
		if [ -d "${jail_procdir}" ] ; then
			umount -f ${jail_procdir} >/dev/null 2>&1
		fi
	fi
	if checkyesno jail_mount; then
		[ -f "${jail_fstab}" ] || warn "${jail_fstab} does not exist"
		umount -a -F "${jail_fstab}" >/dev/null 2>&1
	fi
}

jail_start()
{
	echo -n 'Configuring jails:'
	set_sysctl jail_set_hostname_allow security.jail.set_hostname_allowed \
	    set_hostname_allow
	set_sysctl jail_socket_unixiproute_only \
	    security.jail.socket_unixiproute_only unixiproute_only
	set_sysctl jail_sysvipc_allow security.jail.sysvipc_allowed \
	    sysvipc_allow
	echo '.'

	echo -n 'Starting jails:'
	_tmp_dir=`mktemp -d /tmp/jail.XXXXXXXX` || \
	    err 3 "$name: Can't create temp dir, exiting..."
	for _jail in ${jail_list}
	do
		init_variables $_jail
		if [ -f /var/run/jail_${_jail}.id ]; then
			echo -n " [${jail_hostname} already running (/var/run/jail_${_jail}.id exists)]"
			continue;
		fi
		if [ -n ${jail_interface} ]; then
			ifconfig ${jail_interface} alias ${jail_ip} netmask 255.255.255.255
		fi
		if checkyesno jail_mount; then
			info "Mounting fstab for jail ${_jail} (${jail_fstab})"
			if [ ! -f "${jail_fstab}" ]; then
				err 3 "$name: ${jail_fstab} does not exist"
			fi
			mount -a -F "${jail_fstab}"
		fi
		if checkyesno jail_devfs; then
			# If devfs is already mounted here, skip it.
			df -t devfs "${jail_devdir}" >/dev/null
			if [ $? -ne 0 ]; then
				info "Mounting devfs on ${jail_devdir}"
				devfs_mount_jail "${jail_devdir}" ${jail_ruleset}
				# Transitional symlink for old binaries
				if [ ! -L "${jail_devdir}/log" ]; then
					__pwd="`pwd`"
					cd "${jail_devdir}"
					ln -sf ../var/run/log log
					cd "$__pwd"
				fi
			fi

			# XXX - It seems symlinks don't work when there
			#	is a devfs(5) device of the same name.
			# Jail console output
			#	__pwd="`pwd`"
			#	cd "${jail_devdir}"
			#	ln -sf ../var/log/console console
			#	cd "$__pwd"
		fi
		if checkyesno jail_fdescfs; then
			info "Mounting fdescfs on ${jail_fdescdir}"
			mount -t fdescfs fdesc "${jail_fdescdir}"
		fi
		if checkyesno jail_procfs; then
			info "Mounting procfs onto ${jail_procdir}"
			if [ -d "${jail_procdir}" ] ; then
				mount -t procfs proc "${jail_procdir}"
			fi
		fi
		_tmp_jail=${_tmp_dir}/jail.$$
		eval jail ${jail_flags} -i ${jail_rootdir} ${jail_hostname} \
			${jail_ip} ${jail_exec_start} > ${_tmp_jail} 2>&1
		[ "$?" -eq 0 ] && echo -n " $jail_hostname"
		_jail_id=$(head -1 ${_tmp_jail})
		tail +2 ${_tmp_jail} >${jail_rootdir}/var/log/console.log
		rm -f ${_tmp_jail}
		echo ${_jail_id} > /var/run/jail_${_jail}.id
	done
	rmdir ${_tmp_dir}
	echo '.'
}

jail_stop()
{
	echo -n 'Stopping jails:'
	for _jail in ${jail_list}
	do
		if [ -f "/var/run/jail_${_jail}.id" ]; then
			_jail_id=$(cat /var/run/jail_${_jail}.id)
			if [ ! -z "${_jail_id}" ]; then
				init_variables $_jail
				if [ -n "${jail_exec_stop}" ]; then
					eval env -i /usr/sbin/jexec ${_jail_id} ${jail_exec_stop} \
						>> ${jail_rootdir}/var/log/console.log 2>&1
				fi
				killall -j ${_jail_id} -TERM > /dev/null 2>&1
				sleep 1
				killall -j ${_jail_id} -KILL > /dev/null 2>&1
				jail_umount_fs
				echo -n " $jail_hostname"
			fi
			if [ -n ${jail_interface} ]; then
				ifconfig ${jail_interface} -alias ${jail_ip}
			fi
			rm /var/run/jail_${_jail}.id
		else
			echo "cannot stop jail ${_jail}. No jail id in /var/run"
		fi
	done
	echo '.'
}

load_rc_config $name
cmd="$1"
if [ $# -gt 0 ]; then
	shift
fi
if [ -n "$*" ]; then
	jail_list="$*"
fi
run_rc_command "${cmd}"