1#!/bin/bash
2#============================================================================
3# ${XEN_SCRIPT_DIR}/vif-bridge
4#
5# Script for configuring a vif in bridged mode.
6#
7# Usage:
8# vif-bridge (add|remove|online|offline)
9#
10# Environment vars:
11# vif         vif interface name (required).
12# XENBUS_PATH path to this device's details in the XenStore (required).
13#
14# Read from the store:
15# bridge  bridge to add the vif to (optional).  Defaults to searching for the
16#         bridge itself.
17# ip      list of IP networks for the vif, space-separated (optional).
18#
19# up:
20# Enslaves the vif interface to the bridge and adds iptables rules
21# for its ip addresses (if any).
22#
23# down:
24# Removes the vif interface from the bridge and removes the iptables
25# rules for its ip addresses (if any).
26#============================================================================
27
28dir=$(dirname "$0")
29. "$dir/vif-common.sh"
30
31bridge=${bridge:-}
32bridge=$(xenstore_read_default "$XENBUS_PATH/bridge" "$bridge")
33
34if [ -z "$bridge" ]
35then
36  bridge=$(brctl show | awk 'NR==2{print$1}')
37
38  if [ -z "$bridge" ]
39  then
40     fatal "Could not find bridge, and none was specified"
41  fi
42else
43  #
44  # Old style bridge setup with netloop, used to have a bridge name
45  # of xenbrX, enslaving pethX and vif0.X, and then configuring
46  # eth0.
47  #
48  # New style bridge setup does not use netloop, so the bridge name
49  # is ethX and the physical device is enslaved pethX
50  #
51  # So if...
52  #
53  #   - User asks for xenbrX
54  #   - AND xenbrX doesn't exist
55  #   - AND there is a ethX device which is a bridge
56  #
57  # ..then we translate xenbrX to ethX
58  #
59  # This lets old config files work without modification
60  #
61  if [ ! -e "/sys/class/net/$bridge" ] && [ -z "${bridge##xenbr*}" ]
62  then
63     if [ -e "/sys/class/net/eth${bridge#xenbr}/bridge" ]
64     then
65        bridge="eth${bridge#xenbr}"
66     fi
67  fi
68fi
69
70RET=0
71ip link show dev "$bridge" 1>/dev/null 2>&1 || RET=1
72if [ "$RET" -eq 1 ]
73then
74    fatal "Could not find bridge device $bridge"
75fi
76
77case "$command" in
78    online)
79        setup_virtual_bridge_port "$dev"
80        set_mtu "$bridge" "$dev"
81        add_to_bridge "$bridge" "$dev"
82        ;;
83
84    offline)
85        do_without_error brctl delif "$bridge" "$dev"
86        do_without_error ifconfig "$dev" down
87        ;;
88
89    add)
90        setup_virtual_bridge_port "$dev"
91        set_mtu "$bridge" "$dev"
92        add_to_bridge "$bridge" "$dev"
93        ;;
94esac
95
96handle_iptable
97
98call_hooks vif post
99
100log debug "Successful vif-bridge $command for $dev, bridge $bridge."
101if [ "$type_if" = vif -a "$command" = "online" ]
102then
103  success
104fi
105