#!/bin/sh
#  Copyright (C) 2000-2009, Parallels, Inc. All rights reserved.
#
#  This program is free software; you can redistribute it and/or modify
#  it under the terms of the GNU General Public License as published by
#  the Free Software Foundation; either version 2 of the License, or
#  (at your option) any later version.
#
#  This program is distributed in the hope that it will be useful,
#  but WITHOUT ANY WARRANTY; without even the implied warranty of
#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#  GNU General Public License for more details.
#
#  You should have received a copy of the GNU General Public License
#  along with this program; if not, write to the Free Software
#  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
#
#
# Common stuff for vzctl helper scripts

# get the name of the script
SELFNAME="${0##*/}"

# Set the sane umask
umask 022

# Error codes
VZ_INVALID_PARAMETER_SYNTAX=20
VZ_FS_NO_DISK_SPACE=46
VZ_FS_BAD_TMPL=47
VZ_FS_NEW_VE_PRVT=48
VZ_CHANGEPASS=74
VZ_CANT_ADDIP=34
VZ_IP_INUSE=78

# iptables parameters
VE_STATE_DIR="/var/lib/vzctl/veip/"
CONF_DIR="@PKGCONFDIR@/conf/"

ARPSEND_CMD="arpsend -c 1 -w 1"
IP_CMD=/sbin/ip

# Prints error message and exits
# Parameters:
#   $1 - error message
#   $2 - exit code
# Example of usage:
#   vzerror "Fatal error" 1
vzerror()
{
	# print errors to stderr too
	ERR=$?
	echo "$SELFNAME ERROR: $1" 1>&2
	exit $2
}

# Prints warning message
# Parameters:
#   $1 - a message
# Example of usage:
#   vzwarning 'Invalid user'
vzwarning()
{
	echo "$SELFNAME WARNING: $1" 1>&2
}

# Prints debug message
# Parameters:
#   $* - debug message
# Example of usage:
#   vzdebug Trying to start ls
vzdebug()
{
	echo "$SELFNAME: $*" 1>&2
}

# Checks if environment variable exists,
# and exits with exit code 1 if not
# Parameters:
#   $* - option names
# Example:
#   vzcheckvar VEID IP_ADDR
vzcheckvar()
{
	local var

	for var; do
		eval test -n "\"\$$var\"" ||
			vzerror "Missing parameter: $var" $VZ_INVALID_PARAMETER_SYNTAX
	done
}

# This function fills $NETDEVICES with all network interfaces
# You should always call it before calling vzarp
vzgetnetdev()
{
	# Get a list of interfaces, excluding ones with LOOPBACK,
	# NOARP, or SLAVE flags
	NETDEVICES=`${IP_CMD} addr list | awk '
	/^[0-9]+: / {
		dev="";
	}
	/^[0-9]+: / && /\<UP\>/ && !/\<LOOPBACK\>/ \
			&& !/\<SLAVE\>/ && !/\<NOARP\>/ {
		if ($2 !~ /^veth[0-9]+/)
			dev=$2;
	}
	/^[\ \t]+inet6? / {
		if (dev != "") print (dev);
		dev="";
	}' | sed -e 's/:$//' -e 's/@.*$//'`
}

# Find neighbour interfaces for a given CT IP.
# Make sure to source @PKGCONFDIR@/vz.conf before calling this,
# in order to get the value of $NEIGHBOUR_DEVS from it.
vz_get_neighbour_devs()
{
	[ -n "$NETDEVICES" ] || vzwarning 'Device list is empty'
	[ -n "$1" -a -n "$NETDEVICES" ] || return 1

	if [ "$NEIGHBOUR_DEVS" != 'detect' ]; then
		echo $NETDEVICES
		return 0
	fi

	local route devs dev netdev

	route="$(${IP_CMD} route get "$1" |grep ' dev .* src ')"
	# match: $1 ... dev $dev ...
	devs="$(echo "$route" |sed -ne '/ via /! s/^.* dev \+\([^ ]\+\) .*$/\1/p;Q')"
	[ -n "$devs" ] ||
	# match: $1 ... via $1 ... dev $dev ...
	devs="$(echo "$route" |sed -ne 's/^\([^ ]\+\) \(.* \)\?via \+\1 \(.* \)\?dev \+\([^ ]\+\) .*$/\4/p;Q')"
	[ -n "$devs" ] || return 0

	for netdev in $NETDEVICES; do
		for dev in $devs; do
			if [ "$dev" = "$netdev" ]; then
				echo "$dev"
			fi
		done
	done
}

# Adds/deletes public ARP records for given IP for all interfaces
# Parameters:
#   $1		- should be either "add" or "del"
#   $2		- IP address
#   $NETDEVICES - Network devices used to take MAC addresses from
vzarp()
{
	local dev

	for dev in $(vz_get_neighbour_devs "$2"); do
		${IP_CMD} neigh "$1" proxy "$2" dev "$dev" >/dev/null 2>&1

		# Send ARP request to update neighbour ARP caches
		if [ "$1" = "add" ]; then
			${ARPSEND_CMD} -U -i "$2" -e "$2" "$dev" ||
				vzwarning "$ARPSEND_CMD -U -i $2 -e $2 $dev FAILED"
		fi
	done
}

# Send ARP request to detect that somebody already have this IP
vzarpipdetect()
{
	[ -n "$1" ] || return
	[ "$SKIP_ARPDETECT" = 'yes' ] && return
	local errwarn
	[ "$ERROR_ON_ARPFAIL" = 'yes' ] && errwarn=vzerror || errwarn=vzwarning

	local dev ip

	for ip in $1; do
		for dev in $(vz_get_neighbour_devs "$ip"); do
			${ARPSEND_CMD} -D -e "$ip" "$dev" ||
				$errwarn "$ARPSEND_CMD -D -e $ip $dev FAILED" 1
		done
	done
}

vzaddrouting4()
{
	local src_addr=

	if [ -n "$VE_ROUTE_SRC_DEV" ]; then
		src_addr=`${IP_CMD} route list table local dev "$VE_ROUTE_SRC_DEV" |
			grep '^local' | cut -d' ' -f2 | grep -v '^127\.' | head -n 1`
		[ -n "$src_addr" ] ||
			vzerror "Unable to get source ip [${VE_ROUTE_SRC_DEV}]" $VZ_CANT_ADDIP
		src_addr="src $src_addr"
	fi
	${IP_CMD} route add "$1" dev venet0 $src_addr ||
		vzerror "Unable to add route ${IP_CMD} route add $1 dev venet0 $src_addr" $VZ_CANT_ADDIP
}

vzaddrouting6()
{
	${IP_CMD} route add "$1" dev venet0 ||
		vzerror "Unable to add route ${IP_CMD} route add $1 dev venet0" $VZ_CANT_ADDIP
}

# Sets VE0 source routing for given IP
# Parameters:
#   $1 - IP address
vzaddrouting()
{

	${IP_CMD} route list table all "$1" | fgrep -qs "$1 dev venet0" &&
		return 0
	if [ "${1#*:}" = "$1" ]; then
		vzaddrouting4 "$1"
	else
		vzaddrouting6 "$1"
	fi
}

# Deletes VE0 source routing for given IP
# Parameters:
#   $1 - IP address
vzdelrouting()
{
	${IP_CMD} route list table all "$1" | fgrep -qs "$1 dev venet0" ||
		return 0
	local arg

	if [ "${1%%:*}" = "$1" ]; then
		arg="route del $1 dev venet0"
	else
		arg="-6 route flush $1 dev venet0"
	fi
	${IP_CMD} $arg ||
		vzwarning "vzdelrouting: ${IP_CMD} $arg failed"
}
