#!/bin/sh
#
# Copyright (c) 2010, Yavuz Gokirmak
#
# All rights reserved.
#
# This source code may be used, modified, copied, distributed, and
# sold, in both source and binary form provided that the above
# copyright and these terms are retained, verbatim, as the first
# lines of this file. Under no circumstances is the author
# responsible for the proper functioning of the software nor does
# the author assume any responsibility for damages incurred with
# its use.
#
# $FreeBSD$
#
# This script creates and connects n router like nodes. Complex wide
# area topologies can be created with the help of script.
#
# Virtual nodes are generated via jails and network connections are
# established using ng_eiface(4) node types.
#
# To use this script:
#
# 0. Make your own copy of this example script.
#
# 1. Edit the definition of ${TARGET_TOPOLOGY} to define your virtual
# nodes. Virtual topology definition includes node names and their
# IP address. Target top. syntax: ( name|ip<->name|ip ... )
# Example 1: ( n1|10.0.2.1/30<->n2|10.0.2.2/30 ...)
# Example 2: ( n1|2001:b90::14a/125<->n1|2001:b90::14b/125 ...)
#
# 2. Run this script with "start" as the command line argument.
#
# 3. Add necessary static route commands for each virtual node. For
# example assume you have three virtual nodes connected each other
# like a chain (n1 is connected to n2, n2 is connected to n3).
# In order to establish connectivity among these virtual nodes,
# you have to add default routes to node n1 and node n3. Example
# static route command is:
# STATIC_ROUTE0="jexec n1 route add -inet default 10.0.2.2"
# STATIC_ROUTE1="jexec n3 route add -inet default 10.0.2.5"
# After defining default routes with above format you have to set
# the total number of static route commands as:
# STATIC_ROUTE_CNT=2
#
# 4. Stop bridging by running this script with "stop" as the
# command line argument.
#
# 5. This script uses a template file in order to carry information
# between start and stop calls.
# In the start call, the netgraph interfaces and jails are created.
# At the stop phase, all created objects should be removed.
# DO NOT delete the temporary file between the start and stop phases.
#
# Target Topology:
#
# +---------------+ +---------------------------------------------+
# | n1 (vimage) | | n2 (vimage) |
# | | | |
# | +-----------+ | | +-----------+ +-----------+ +-----------+ |
# | | ngeth0 | | | | ngeth1 | | ngeth2 | | ngeth4 | |
# | |(ng_eiface)| | | |(ng_eiface)| |(ng_eiface)| |(ng_eiface)| |
# | +--+-----+--+ | | +--+-----+--+ +--+-----+--+ +--+-----+--+ |
# | |ether| | | |ether| |ether| |ether| |
# | +-X---+ | | +--X--+ +--X--+ +--X--+ |
# +-------X-------+ +------X--------------X---------------X-------+
# X X X X
# X X X X
# XXXXXXXXXXXXXXX X X
# X X
# +--------X------+ +--------X------+
# | -+--X--+- | | -+--X--+- |
# | |ether| | | |ether| |
# | +--+-----+--+ | | +--+-----+--+ |
# | | ngeth3 | | | | ngeth5 | |
# | |(ng_eiface)| | | |(ng_eiface)| |
# | +-----------+ | | +-----------+ |
# | | | |
# | n3 (vimage) | | n4 (vimage) |
# +---------------+ +---------------+
#
#
#
# List the names of virtual nodes and their IP addresses. Use ':'
# character to separate node name from node IP address and netmask.
TARGET_TOPOLOGY="n1|10.0.2.1/30<->n2|10.0.2.2/30 n2|10.0.2.5/30<->n3|10.0.2.6/30 n2|10.0.2.9/30<->n4|10.0.2.10/30"
STATIC_ROUTE0="jexec n1 route add -inet default 10.0.2.2"
STATIC_ROUTE1="jexec n3 route add -inet default 10.0.2.5"
STATIC_ROUTE2="jexec n4 route add -inet default 10.0.2.9"
STATIC_ROUTE_CNT=3
# MAC manufacturer prefix. This can be modified according to needs.
MAC_PREFIX="00:1d:92"
# Temporary file is important for proper execution of script.
TEMP_FILE="/var/tmp/.virtual.chain.tmp"
# Set root directory for jails to be created.
JAIL_PATH="/usr/jails/router"
####################################################################
#### Nothing below this point should need to be modified. ####
####################################################################
# Start/restart routine.
virtual_chain_start() {
# Load netgraph KLD's as necessary.
for KLD in ng_ether ng_bridge ng_eiface; do
if ! kldstat -v | grep -qw ${KLD}; then
echo -n "Loading ${KLD}.ko... "
kldload ${KLD} || exit 1
echo "done"
fi
done
# Reset all interfaces and jails. If temporary file can not be found
# script assumes that there is no previous configuration.
if [ ! -e ${TEMP_FILE} ]; then
echo "No previous configuration(${TEMP_FILE}) found to clean-up."
else
echo -n "Cleaning previous configuration..."
virtual_chain_stop
echo "done"
fi
# Create temporary file for usage. This file includes generated
# interface names and jail names. All bridges, interfaces and jails
# are written to file while created. In clean-up process written
# objects are cleaned (i.e. removed) from system.
if [ -e ${TEMP_FILE} ]; then
touch ${TEMP_FILE}
fi
# Attach other interfaces as well.
for CONNECTION in ${TARGET_TOPOLOGY}; do
# Virtual connections are defined in TARGET_TOPOLOGY variable.
# They have the form of 'nodeName|IPaddr'. Below two lines split
PEER1=`echo ${CONNECTION} | awk -F"<->" '{print $1}'`
PEER1_NAME=`echo ${PEER1} | awk -F"|" '{print $1}'`
PEER1_IP=`echo ${PEER1} | awk -F"|" '{print $2}'`
PEER2=`echo ${CONNECTION} | awk -F"<->" '{print $2}'`
PEER2_NAME=`echo ${PEER2} | awk -F"|" '{print $1}'`
PEER2_IP=`echo ${PEER2} | awk -F"|" '{print $2}'`
# !!! if not created already..
# Create virtual node (jail) with given name and using
# JAIL_PATH as root directory for jail.
virtual_chain_create_peer_if_necessary ${PEER1_NAME}
virtual_chain_create_peer_if_necessary ${PEER2_NAME}
# create an interface for peer with the given peer IP. Get interface
# for future use; you will connect this interface to the other
# peers' (PEER2) interface.
virtual_chain_create_interface_with_ip ${PEER1_NAME} ${PEER1_IP}
PEER1_INTERFACE=${RET_INTERFACE}
# create an interface for peer with the given peer IP. Get interface
# for future use; you will connect this interface to the other
# peers' (PEER2) interface.
virtual_chain_create_interface_with_ip ${PEER2_NAME} ${PEER2_IP}
PEER2_INTERFACE=${RET_INTERFACE}
# Connect virtual interface to other interface. Syntax is :
# ngctl connect INTERFACE1: INTERFACE2: ether ether.
echo -n "Connecting ${PEER1_INTERFACE}:ether to ${PEER2_INTERFACE}:ether..."
ngctl connect ${PEER1_INTERFACE}: ${PEER2_INTERFACE}: ether ether \
|| exit 1
echo "done"
done
# Executes static route add commands.
i=0
while [ $i != $STATIC_ROUTE_CNT ]; do
eval ROUTE=\${STATIC_ROUTE${i}}
ret=`${ROUTE}`
i=`expr $i + 1`
done
echo "Virtual WAN established successfully!"
}
virtual_chain_create_interface_with_ip() {
NODE_NAME=$1
NODE_IP=$2
# Create a ng_eiface object for virtual node. ng_eiface
# object has a hook that can be connected to one of bridge
# links. After creating interface get its automatically
# generated name for further usage.
echo "Creating eiface interface for virtual node ${NODE_NAME}."
ngctl mkpeer eiface ether ether
EIFACE=`ngctl l | grep ngeth | tail -n 1| awk '{print $2}'`
echo "Interface ${EIFACE} is created."
# Write name of the interface to temp file. Clean-up procedure
# will use this name to shutdown interface.
echo "interface ${EIFACE}" >> ${TEMP_FILE}
# Move virtual interface to virtual node. Note that Interface
# name will not be changed at the end of this movement. Moved
# interface can be seen at the output of ifconfig command in
# jail: 'jexec jailname ifconfig'
echo "Moving ${EIFACE} to ${NODE_NAME}"
ifconfig ${EIFACE} vnet ${NODE_NAME}
# Make lo0 interface localhost.
jexec ${NODE_NAME} ifconfig lo0 localhost
# Generate a random mac address for virtual interface. First
# three octets can be changed by user. Last three octets are
# generated randomly.
M4=`od -An -N2 -i /dev/random | sed -e 's/ //g' | \
awk '{ print $1 % 256 }'`
M5=`od -An -N2 -i /dev/random | sed -e 's/ //g' | \
awk '{ print $1 % 256 }'`
M6=`od -An -N2 -i /dev/random | sed -e 's/ //g' | \
awk '{ print $1 % 256 }'`
MAC=`printf ${MAC_PREFIX}:%02x:%02x:%02x ${M4} ${M5} ${M6}`
# Set the link address (mac address) of virtual interface in
# virtual node to randomly generated MAC.
echo "Setting MAC address of ${EIFACE} to '${MAC}'"
jexec ${NODE_NAME} ifconfig ${EIFACE} link $MAC
# Either IPv4 or IPv6 can be used in this script. Ifconfig
# IP setting syntax differs slightly for two IP versions.
# For version 4 'inet' keyword is used whereas for version 6
# 'inet6' is used. Below line tries to decide which IP version
# is given and sets IPVER to 'inet' or 'inet6'.
IPVER=`echo ${NODE_IP} | awk -F"." '{ split($4,last,"/"); \
if( NF==4 && $1>0 && $1<256 && $2<256 && $3<256 && \
last[1]<256) print "inet"; else print "inet6"}'`
# Set IP address of virtual interface in virtual node.
echo "Setting IP address of ${EIFACE} to '${NODE_IP}'"
jexec ${NODE_NAME} ifconfig ${EIFACE} ${IPVER} ${NODE_IP}
RET_INTERFACE=${EIFACE}
}
virtual_chain_create_peer_if_necessary() {
if ! grep -q $1 ${TEMP_FILE} ; then
echo -n "Creating virtual node (jail) ${1}..."
jail -c vnet name=${1} host.hostname=${1} \
path=${JAIL_PATH} persist
jexec ${1} sysctl -w net.inet.ip.forwarding=1
jexec ${1} sysctl -w net.inet6.ip6.forwarding=1
echo "done"
# Write name of the jail to temp file. Clean-up
# procedure will use this name to remove jail.
echo "node ${1}" >> ${TEMP_FILE}
fi
}
# Stop routine.
virtual_chain_stop() {
if [ ! -e ${TEMP_FILE} ]; then
echo "Nothing to stop! ${TEMP_FILE}: temp file not found"
else
echo -n "Shutdown bridge interface.."
OBJECTS=`cat ${TEMP_FILE} | grep bridge | awk '{print $2}'`
for BRIDGE in ${OBJECTS}; do
ngctl shutdown ${BRIDGE}: >/dev/null 2>&1
done
echo "done"
echo -n "Shutdown all eiface interfaces..."
OBJECTS=`cat ${TEMP_FILE} | grep interface | awk '{print $2}'`
for INTERFACE in ${OBJECTS}; do
ngctl shutdown ${INTERFACE}: >/dev/null 2>&1
done
echo "done"
echo -n "Removing all jails..."
OBJECTS=`cat ${TEMP_FILE} | grep node | awk '{print $2}'`
for NODE in ${OBJECTS}; do
jail -r ${NODE}
done
echo "done"
echo "Removing tempfile ${TEMP_FILE}"
rm ${TEMP_FILE}
fi
echo "Virtual LAN objects removed successfully!"
}
virtual_chain_usage() {
echo "usage: $0 start [target_topology]"
echo " : $0 [ stop | help ]"
}
# Main entry point.
case $# in
1)
case $1 in
start)
echo -n "Creating default target topology:"
echo " ${TARGET_TOPOLOGY}"
virtual_chain_start
;;
stop)
if [ ! -e ${TEMP_FILE} ]; then
echo -n "Noting to stop! ${TEMP_FILE}:"
echo " temp file not found"
else
virtual_chain_stop
fi
;;
help)
virtual_chain_usage
exit 1
;;
*)
virtual_chain_usage
exit 1
esac
;;
2)
case $1 in
start)
TARGET_TOPOLOGY=$2
echo -n "Creating target topology:"
echo "${TARGET_TOPOLOGY}"
virtual_chain_start
;;
*)
virtual_chain_usage
exit 1
esac
;;
*)
virtual_chain_usage
exit 1
esac