xref: /freebsd/share/examples/netgraph/virtual.chain (revision 63a938566d524836885917d95bd491aa4400b181)
1#!/bin/sh
2#
3# Copyright (c) 2010, Yavuz Gokirmak
4#
5# All rights reserved.
6#
7# This source code may be used, modified, copied, distributed, and
8# sold, in both source and binary form provided that the above
9# copyright and these terms are retained, verbatim, as the first
10# lines of this file.  Under no circumstances is the author
11# responsible for the proper functioning of the software nor does
12# the author assume any responsibility for damages incurred with
13# its use.
14#
15# $FreeBSD$
16#
17# This script creates and connects n router like nodes. Complex wide
18# area topologies can be created with the help of script.
19#
20# Virtual nodes are generated via jails and network connections are
21# established using ng_eiface(4) node types.
22#
23# To use this script:
24#
25# 0. Make your own copy of this example script.
26#
27# 1. Edit the definition of ${TARGET_TOPOLOGY} to define your virtual
28#    nodes. Virtual topology definition includes node names and their
29#    IP address. Target top. syntax: ( name|ip<->name|ip ... )
30#    Example 1: ( n1|10.0.2.1/30<->n2|10.0.2.2/30 ...)
31#    Example 2: ( n1|2001:b90::14a/125<->n1|2001:b90::14b/125 ...)
32#
33# 2. Run this script with "start" as the command line argument.
34#
35# 3. Add necessary static route commands for each virtual node. For
36#    example assume you have three virtual nodes connected each other
37#    like a chain (n1 is connected to n2, n2 is connected to n3).
38#    In order to establish connectivity among these virtual nodes,
39#    you have to add default routes to node n1 and node n3. Example
40#    static route command is:
41#      STATIC_ROUTE0="jexec n1 route add -inet default 10.0.2.2"
42#      STATIC_ROUTE1="jexec n3 route add -inet default 10.0.2.5"
43#    After defining default routes with above format you have to set
44#    the total number of static route commands as:
45#      STATIC_ROUTE_CNT=2
46#
47# 4. Stop bridging by running this script with "stop" as the
48#    command line argument.
49#
50# 5. This script uses a template file in order to carry information
51#    between start and stop calls.
52#      In the start call, the netgraph interfaces and jails are created.
53#      At the stop phase, all created objects should be removed.
54#    DO NOT delete the temporary file between the start and stop phases.
55#
56# Target Topology:
57#
58# +---------------+  +---------------------------------------------+
59# |  n1 (vimage)  |  |                 n2 (vimage)                 |
60# |               |  |                                             |
61# | +-----------+ |  | +-----------+  +-----------+  +-----------+ |
62# | |  ngeth0   | |  | |  ngeth1   |  |  ngeth2   |  |  ngeth4   | |
63# | |(ng_eiface)| |  | |(ng_eiface)|  |(ng_eiface)|  |(ng_eiface)| |
64# | +--+-----+--+ |  | +--+-----+--+  +--+-----+--+  +--+-----+--+ |
65# |    |ether|    |  |    |ether|        |ether|        |ether|    |
66# |    +-X---+    |  |    +--X--+        +--X--+        +--X--+    |
67# +-------X-------+  +------X--------------X---------------X-------+
68#         X                X              X                X
69#          X               X             X                X
70#           XXXXXXXXXXXXXXX            X                  X
71#                                    X                    X
72#                          +--------X------+     +--------X------+
73#                          |   -+--X--+-   |     |   -+--X--+-   |
74#                          |    |ether|    |     |    |ether|    |
75#                          | +--+-----+--+ |     | +--+-----+--+ |
76#                          | |  ngeth3   | |     | |  ngeth5   | |
77#                          | |(ng_eiface)| |     | |(ng_eiface)| |
78#                          | +-----------+ |     | +-----------+ |
79#                          |               |     |               |
80#                          |  n3 (vimage)  |     |  n4 (vimage)  |
81#                          +---------------+     +---------------+
82#
83#
84#
85
86# List the names of virtual nodes and their IP addresses. Use ':'
87# character to separate node name from node IP address and netmask.
88
89TARGET_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"
90STATIC_ROUTE0="jexec n1 route add -inet default 10.0.2.2"
91STATIC_ROUTE1="jexec n3 route add -inet default 10.0.2.5"
92STATIC_ROUTE2="jexec n4 route add -inet default 10.0.2.9"
93STATIC_ROUTE_CNT=3
94
95# MAC manufacturer prefix. This can be modified according to needs.
96MAC_PREFIX="00:1d:92"
97
98# Temporary file is important for proper execution of script.
99TEMP_FILE="/var/tmp/.virtual.chain.tmp"
100
101# Set root directory for jails to be created.
102JAIL_PATH="/usr/jails/router"
103
104
105####################################################################
106####    Nothing below this point should need to be modified.    ####
107####################################################################
108
109
110# Start/restart routine.
111virtual_chain_start() {
112
113	# Load netgraph KLD's as necessary.
114
115	for KLD in ng_ether ng_bridge ng_eiface; do
116		if ! kldstat -v | grep -qw ${KLD}; then
117			echo -n "Loading ${KLD}.ko... "
118			kldload ${KLD} || exit 1
119			echo "done"
120		fi
121	done
122
123	# Reset all interfaces and jails. If temporary file can not be found
124	# script assumes that there is no previous configuration.
125
126	if [ ! -e ${TEMP_FILE} ]; then
127		echo "No previous configuration(${TEMP_FILE}) found to clean-up."
128	else
129		echo -n "Cleaning previous configuration..."
130		virtual_chain_stop
131		echo "done"
132	fi
133
134	# Create temporary file for usage. This file includes generated
135	# interface names and jail names. All bridges, interfaces and jails
136	# are written to file while created. In clean-up process written
137	# objects are cleaned (i.e. removed) from system.
138
139	if [ -e ${TEMP_FILE} ]; then
140		touch ${TEMP_FILE}
141	fi
142
143
144	# Attach other interfaces as well.
145	for CONNECTION in ${TARGET_TOPOLOGY}; do
146
147		# Virtual connections are defined in TARGET_TOPOLOGY variable.
148		# They have the form of 'nodeName|IPaddr'. Below two lines split
149
150		PEER1=`echo ${CONNECTION} | awk -F"<->" '{print $1}'`
151		PEER1_NAME=`echo ${PEER1} | awk -F"|" '{print $1}'`
152		PEER1_IP=`echo ${PEER1} | awk -F"|" '{print $2}'`
153
154		PEER2=`echo ${CONNECTION} | awk -F"<->" '{print $2}'`
155		PEER2_NAME=`echo ${PEER2} | awk -F"|" '{print $1}'`
156		PEER2_IP=`echo ${PEER2} | awk -F"|" '{print $2}'`
157
158		# !!! if not created already..
159		# Create virtual node (jail) with given name and using
160		# JAIL_PATH as root directory for jail.
161
162		virtual_chain_create_peer_if_necessary ${PEER1_NAME}
163		virtual_chain_create_peer_if_necessary ${PEER2_NAME}
164
165		# create an interface for peer with the given peer IP. Get interface
166		# for future use; you will connect this interface to the other
167		# peers' (PEER2) interface.
168		virtual_chain_create_interface_with_ip ${PEER1_NAME} ${PEER1_IP}
169		PEER1_INTERFACE=${RET_INTERFACE}
170
171		# create an interface for peer with the given peer IP. Get interface
172		# for future use; you will connect this interface to the other
173		# peers' (PEER2) interface.
174		virtual_chain_create_interface_with_ip ${PEER2_NAME} ${PEER2_IP}
175		PEER2_INTERFACE=${RET_INTERFACE}
176
177		# Connect virtual interface to other interface. Syntax is :
178		# ngctl connect INTERFACE1: INTERFACE2: ether ether.
179
180		echo -n "Connecting ${PEER1_INTERFACE}:ether to ${PEER2_INTERFACE}:ether..."
181		ngctl connect ${PEER1_INTERFACE}: ${PEER2_INTERFACE}: ether ether \
182			|| exit 1
183		echo "done"
184
185	done
186
187	# Executes static route add commands.
188	i=0
189	while [ $i != $STATIC_ROUTE_CNT ]; do
190		eval ROUTE=\${STATIC_ROUTE${i}}
191		ret=`${ROUTE}`
192		i=`expr $i + 1`
193	done
194
195	echo "Virtual WAN established successfully!"
196}
197
198virtual_chain_create_interface_with_ip() {
199
200	NODE_NAME=$1
201	NODE_IP=$2
202
203	# Create a ng_eiface object for virtual node. ng_eiface
204	# object has a hook that can be connected to one of bridge
205	# links. After creating interface get its automatically
206	# generated name for further usage.
207
208	echo "Creating eiface interface for virtual node ${NODE_NAME}."
209	ngctl mkpeer eiface ether ether
210	EIFACE=`ngctl l | grep ngeth | tail -n 1| awk '{print $2}'`
211	echo "Interface ${EIFACE} is created."
212
213	# Write name of the interface to temp file. Clean-up procedure
214	# will use this name to shutdown interface.
215
216	echo "interface ${EIFACE}" >> ${TEMP_FILE}
217
218	# Move virtual interface to virtual node. Note that Interface
219	# name will not be changed at the end of this movement. Moved
220	# interface can be seen at the output of ifconfig command in
221	# jail: 'jexec jailname ifconfig'
222
223	echo "Moving ${EIFACE} to ${NODE_NAME}"
224	ifconfig ${EIFACE} vnet ${NODE_NAME}
225
226	# Make lo0 interface localhost.
227	jexec ${NODE_NAME} ifconfig lo0 localhost
228
229	# Generate a random mac address for virtual interface. First
230	# three octets can be changed by user. Last three octets are
231	# generated randomly.
232	M4=`od -An -N2 -i /dev/random | sed -e 's/ //g' | \
233			awk '{ print $1 % 256 }'`
234	M5=`od -An -N2 -i /dev/random | sed -e 's/ //g' | \
235			awk '{ print $1 % 256 }'`
236	M6=`od -An -N2 -i /dev/random | sed -e 's/ //g' | \
237			awk '{ print $1 % 256 }'`
238
239	MAC=`printf ${MAC_PREFIX}:%02x:%02x:%02x ${M4} ${M5} ${M6}`
240
241	# Set the link address (mac address) of virtual interface in
242	# virtual node to randomly generated MAC.
243	echo "Setting MAC address of ${EIFACE} to '${MAC}'"
244	jexec ${NODE_NAME} ifconfig ${EIFACE} link $MAC
245
246	# Either IPv4 or IPv6 can be used in this script. Ifconfig
247	# IP setting syntax differs slightly for two IP versions.
248	# For version 4 'inet' keyword is used whereas for version 6
249	# 'inet6' is used. Below line tries to decide which IP version
250	# is given and sets IPVER to 'inet' or 'inet6'.
251
252	IPVER=`echo ${NODE_IP} | awk -F"." '{ split($4,last,"/"); \
253		if( NF==4 && $1>0 && $1<256 && $2<256 && $3<256 && \
254		last[1]<256) print "inet"; else print "inet6"}'`
255
256	# Set IP address of virtual interface in virtual node.
257	echo "Setting IP address of ${EIFACE} to '${NODE_IP}'"
258	jexec ${NODE_NAME} ifconfig ${EIFACE} ${IPVER} ${NODE_IP}
259
260	RET_INTERFACE=${EIFACE}
261}
262
263virtual_chain_create_peer_if_necessary() {
264
265	if ! grep -q $1 ${TEMP_FILE} ; then
266
267		echo -n "Creating virtual node (jail) ${1}..."
268		jail -c vnet name=${1} host.hostname=${1} \
269			path=${JAIL_PATH} persist
270		jexec ${1} sysctl -w net.inet.ip.forwarding=1
271		jexec ${1} sysctl -w net.inet6.ip6.forwarding=1
272		echo "done"
273
274		# Write name of the jail to temp file. Clean-up
275		# procedure will use this name to remove jail.
276
277		echo "node ${1}" >> ${TEMP_FILE}
278	fi
279
280}
281
282# Stop routine.
283virtual_chain_stop() {
284
285	if [ ! -e ${TEMP_FILE} ]; then
286		echo "Nothing to stop! ${TEMP_FILE}: temp file not found"
287	else
288
289		echo -n "Shutdown bridge interface.."
290		OBJECTS=`cat ${TEMP_FILE} | grep bridge | awk '{print $2}'`
291		for BRIDGE in ${OBJECTS}; do
292			ngctl shutdown ${BRIDGE}: >/dev/null 2>&1
293		done
294		echo "done"
295
296		echo -n "Shutdown all eiface interfaces..."
297		OBJECTS=`cat ${TEMP_FILE} | grep interface | awk '{print $2}'`
298		for INTERFACE in ${OBJECTS}; do
299			ngctl shutdown ${INTERFACE}: >/dev/null 2>&1
300		done
301		echo "done"
302
303		echo -n "Removing all jails..."
304		OBJECTS=`cat ${TEMP_FILE} | grep node | awk '{print $2}'`
305		for NODE in ${OBJECTS}; do
306			jail -r ${NODE}
307		done
308		echo "done"
309
310		echo "Removing tempfile ${TEMP_FILE}"
311		rm ${TEMP_FILE}
312	fi
313	echo "Virtual LAN objects removed successfully!"
314
315}
316
317virtual_chain_usage() {
318	echo "usage: $0 start [target_topology]"
319	echo "     : $0 [ stop | help ]"
320}
321
322
323# Main entry point.
324
325case $# in
326	1)
327		case $1 in
328                        start)
329                                echo -n "Creating default target topology:"
330				echo " ${TARGET_TOPOLOGY}"
331                                virtual_chain_start
332                                ;;
333                        stop)
334
335				if [ ! -e ${TEMP_FILE} ]; then
336					echo -n "Noting to stop! ${TEMP_FILE}:"
337					echo " temp file not found"
338				else
339					virtual_chain_stop
340				fi
341                                ;;
342                        help)
343                                virtual_chain_usage
344				exit 1
345                                ;;
346                        *)
347                                virtual_chain_usage
348                                exit 1
349
350                esac
351		;;
352	2)
353	        case $1 in
354			start)
355                        	TARGET_TOPOLOGY=$2
356                                echo -n "Creating target topology:"
357				echo "${TARGET_TOPOLOGY}"
358                                virtual_chain_start
359                                ;;
360                        *)
361                        	virtual_chain_usage
362                                exit 1
363                esac
364		;;
365
366	*)
367                virtual_chain_usage
368                exit 1
369esac
370
371