1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
|
#!/bin/bash
#============================================================================
# Default Xen network start/stop script.
# Xend calls a network script when it starts.
# The script name to use is defined in /etc/xen/xend-config.sxp
# in the network-script field.
#
# This script creates a bridge (default ${netdev}), adds a device
# (defaults to the device on the default gateway route) to it, copies
# the IP addresses from the device to the bridge and adjusts the routes
# accordingly.
#
# If all goes well, this should ensure that networking stays up.
# However, some configurations are upset by this, especially
# NFS roots. If the bridged setup does not meet your needs,
# configure a different script, for example using routing instead.
#
# Usage:
#
# network-bridge (start|stop|status) {VAR=VAL}*
#
# Vars:
#
# bridge The bridge to use (default ${netdev}).
# netdev The interface to add to the bridge (default gateway device).
# antispoof Whether to use iptables to prevent spoofing (default no).
#
# Internal Vars:
# pdev="p${netdev}"
# tdev=tmpbridge
#
# start:
# Creates the bridge as tdev
# Copies the IP and MAC addresses from pdev to bridge
# Renames netdev to be pdev
# Renames tdev to bridge
# Enslaves pdev to bridge
#
# stop:
# Removes pdev from the bridge
# Transfers addresses, routes from bridge to pdev
# Renames bridge to tdev
# Renames pdev to netdev
# Deletes tdev
#
# status:
# Print addresses, interfaces, routes
#
#============================================================================
dir=$(dirname "$0")
. "$dir/xen-script-common.sh"
. "$dir/xen-network-common.sh"
findCommand "$@"
evalVariables "$@"
is_network_root () {
local rootfs=$(awk '{ if ($1 !~ /^[ \t]*#/ && $2 == "/") { print $3; }}' /etc/mtab)
local rootopts=$(awk '{ if ($1 !~ /^[ \t]*#/ && $2 == "/") { print $4; }}' /etc/mtab)
[[ "$rootfs" =~ "^nfs" ]] || [[ "$rootopts" =~ "_netdev" ]] && has_nfsroot=1 || has_nfsroot=0
if [ $has_nfsroot -eq 1 ]; then
local bparms=$(cat /proc/cmdline)
for p in $bparms; do
local ipaddr=$(echo $p | awk /nfsroot=/'{ print substr($1,9,index($1,":")-9) }')
if [ "$ipaddr" != "" ]; then
local nfsdev=$(ip route get $ipaddr | awk /$ipaddr/'{ print $3 }')
[[ "$nfsdev" == "$netdev" ]] && return 0 || return 1
fi
done
fi
return 1
}
find_alt_device () {
local interf=$1
local prefix=${interf%[[:digit:]]}
local ifs=$(ip link show | grep " $prefix" |\
gawk '{ printf ("%s",substr($2,1,length($2)-1)) }' |\
sed s/$interf//)
echo "$ifs"
}
netdev=${netdev:-$(ip route list 0.0.0.0/0 | \
sed 's/.*dev \([a-z]\+[0-9]\+\).*$/\1/')}
if is_network_root ; then
altdevs=$(find_alt_device $netdev)
for netdev in $altdevs; do break; done
if [ -z "$netdev" ]; then
[ -x /usr/bin/logger ] && /usr/bin/logger "network-bridge: bridging not supported on network root; not starting"
exit
fi
fi
netdev=${netdev:-eth0}
bridge=${bridge:-${netdev}}
antispoof=${antispoof:-no}
pdev="p${netdev}"
tdev=tmpbridge
get_ip_info() {
addr_pfx=`ip addr show dev $1 | egrep '^ *inet' | sed -e 's/ *inet //' -e 's/ .*//'`
gateway=`ip route show dev $1 | fgrep default | sed 's/default via //'`
}
do_ifup() {
if [ $1 != "${netdev}" ] || ! ifup $1 ; then
if [ -n "$addr_pfx" ] ; then
# use the info from get_ip_info()
ip addr flush $1
ip addr add ${addr_pfx} dev $1
ip link set dev $1 up
[ -n "$gateway" ] && ip route add default via ${gateway}
fi
fi
}
# Usage: transfer_addrs src dst
# Copy all IP addresses (including aliases) from device $src to device $dst.
transfer_addrs () {
local src=$1
local dst=$2
# Don't bother if $dst already has IP addresses.
if ip addr show dev ${dst} | egrep -q '^ *inet ' ; then
return
fi
# Address lines start with 'inet' and have the device in them.
# Replace 'inet' with 'ip addr add' and change the device name $src
# to 'dev $src'.
ip addr show dev ${src} | egrep '^ *inet ' | sed -e "
s/inet/ip addr add/
s@\([0-9]\+\.[0-9]\+\.[0-9]\+\.[0-9]\+/[0-9]\+\)@\1@
s/${src}/dev ${dst} label ${dst}/
s/secondary//
" | sh -e
# Remove automatic routes on destination device
ip route list | sed -ne "
/dev ${dst}\( \|$\)/ {
s/^/ip route del /
p
}" | sh -e
}
# Usage: transfer_routes src dst
# Get all IP routes to device $src, delete them, and
# add the same routes to device $dst.
# The original routes have to be deleted, otherwise adding them
# for $dst fails (duplicate routes).
transfer_routes () {
local src=$1
local dst=$2
# List all routes and grep the ones with $src in.
# Stick 'ip route del' on the front to delete.
# Change $src to $dst and use 'ip route add' to add.
ip route list | sed -ne "
/dev ${src}\( \|$\)/ {
h
s/^/ip route del /
P
g
s/${src}/${dst}/
s/^/ip route add /
P
d
}" | sh -e
}
##
# link_exists interface
#
# Returns 0 if the interface named exists (whether up or down), 1 otherwise.
#
link_exists()
{
if ip link show "$1" >/dev/null 2>/dev/null
then
return 0
else
return 1
fi
}
# Set the default forwarding policy for $dev to drop.
# Allow forwarding to the bridge.
antispoofing () {
iptables -P FORWARD DROP
iptables -F FORWARD
iptables -A FORWARD -m physdev --physdev-in ${pdev} -j ACCEPT
}
find_active_vlans() {
local netdev=$1
local vlan
local vlans
vlans=""
for vifcfg in /etc/sysconfig/network/ifcfg-vlan* ; do
vlan=${vifcfg/*\/ifcfg-}
if [ "$vlan" = "vlan*" ]; then
continue
fi
. $vifcfg
etherdevice="$ETHERDEVICE"
if [ -x /sbin/getcfg-interface ]; then
etherdevice=$(/sbin/getcfg-interface "$ETHERDEVICE")
fi
if [ "$ETHERDEVICE" = "$netdev" ] || [ "$etherdevice" = "$netdev" ] ; then
link_exists "$vlan" && vlans="$vlans $vlan"
fi
done
echo "$vlans"
}
# Usage: show_status dev bridge
# Print ifconfig and routes.
show_status () {
local dev=$1
local bridge=$2
echo '============================================================'
ip addr show ${dev}
ip addr show ${bridge}
echo ' '
brctl show ${bridge}
echo ' '
ip route list
echo ' '
route -n
echo '============================================================'
}
op_start () {
if [ "${bridge}" = "null" ] ; then
return
fi
if link_exists "$pdev"; then
# The device is already up.
return
fi
local bonded=""
[ -e /sys/class/net/${netdev}/bonding ] && bonded="yes"
vlans=$(find_active_vlans "${netdev}")
for vlan in $vlans ; do ifdown $vlan ; done
create_bridge ${tdev}
# Record creation of bridge in /dev/shm/sysconfig/xenbridges so other
# tools, e.g. yast2 lan, know that Xen bridging is active.
[ -d /dev/shm/sysconfig/xenbridges ] || mkdir /dev/shm/sysconfig/xenbridges
touch /dev/shm/sysconfig/xenbridges/${bridge}
preiftransfer ${netdev}
transfer_addrs ${netdev} ${tdev}
# Remember slaves for bonding interface.
if [ -e /sys/class/net/${netdev}/bonding/slaves ]; then
slaves=`cat /sys/class/net/${netdev}/bonding/slaves`
fi
# Remember the IP details for do_ifup.
get_ip_info ${netdev}
if ! ifdown ${netdev}; then
ip link set ${netdev} down
ip addr flush ${netdev}
fi
if [ "x${bonded}" = "xyes" ]
then
ip link set ${tdev} name ${bridge}
ln -sf /etc/sysconfig/network/ifcfg-${netdev} /etc/sysconfig/network/ifcfg-${pdev}
ifup ${pdev}
local gw=`ip route show dev ${pdev} | fgrep default | sed 's/default via //'`
ip addr flush ${pdev}
rm -f /etc/sysconfig/network/ifcfg-${pdev}
brctl addif ${bridge} ${pdev}
ip link set ${bridge} up
[ -n "$gw" ] && ip route add default via ${gw}
else
ip link set ${netdev} name ${pdev}
ip link set ${tdev} name ${bridge}
setup_bridge_port ${pdev}
# Restore slaves
if [ -n "${slaves}" ]; then
ip link set ${pdev} up
ifenslave ${pdev} ${slaves}
fi
add_to_bridge2 ${bridge} ${pdev}
do_ifup ${bridge}
fi
for vlan in $vlans ; do ifup $vlan ; done
if [ ${antispoof} = 'yes' ] ; then
antispoofing
fi
}
op_stop () {
if [ "${bridge}" = "null" ]; then
return
fi
if ! link_exists "$bridge"; then
return
fi
vlans=$(find_active_vlans "${netdev}")
for vlan in $vlans ; do ifdown $vlan ; done
transfer_addrs ${bridge} ${pdev}
if ! ifdown ${bridge}; then
get_ip_info ${bridge}
ip link set ${pdev} down
ip addr flush ${bridge}
brctl delif ${bridge} ${pdev}
ip link set ${bridge} down
ip link set ${bridge} name ${tdev}
brctl delbr ${tdev}
fi
ip link set ${pdev} down
ip link set ${pdev} name ${netdev}
do_ifup ${netdev}
# Remove record of bridge from /dev/shm/sysconfig/xenbridges ...
rm -f /dev/shm/sysconfig/xenbridges/${bridge}
# ... and directory itself if empty
if [ -z "$(ls -A /dev/shm/sysconfig/xenbridges 2>/dev/null)" ]; then
rmdir /dev/shm/sysconfig/xenbridges
fi
for vlan in $vlans ; do ifup $vlan ; done
}
# adds $dev to $bridge but waits for $dev to be in running state first
add_to_bridge2() {
local bridge=$1
local dev=$2
local maxtries=10
echo -n "Waiting for ${dev} to negotiate link."
ip link set ${dev} up
for i in `seq ${maxtries}` ; do
if ifconfig ${dev} | grep -q RUNNING ; then
break
else
echo -n '.'
sleep 1
fi
done
if [ ${i} -eq ${maxtries} ] ; then echo -n '(link isnt in running state)' ; fi
echo
add_to_bridge ${bridge} ${dev}
}
case "$command" in
start)
op_start
;;
stop)
op_stop
;;
status)
show_status ${netdev} ${bridge}
;;
*)
echo "Unknown command: $command" >&2
echo 'Valid commands are: start, stop, status' >&2
exit 1
esac
|