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Diffstat (limited to 'tools/python/xen/util/Brctl.py')
| -rw-r--r-- | tools/python/xen/util/Brctl.py | 160 |
1 files changed, 160 insertions, 0 deletions
diff --git a/tools/python/xen/util/Brctl.py b/tools/python/xen/util/Brctl.py new file mode 100644 index 0000000000..9d3eba1e5f --- /dev/null +++ b/tools/python/xen/util/Brctl.py @@ -0,0 +1,160 @@ +"""Bridge control utilities. +""" +import os +import os.path +import re +import sys + +os.defpath = os.defpath + ':/sbin:/usr/sbin:/usr/local/sbin' +CMD_IFCONFIG = 'ifconfig' +CMD_ROUTE = 'route' +CMD_BRCTL = 'brctl' +CMD_IPTABLES = "iptables" + +opts = None + +class Opts: + + def __init__(self, defaults): + for (k, v) in defaults.items(): + setattr(self, k, v) + pass + +def cmd(p, s): + """Print and execute command 'p' with args 's'. + """ + global opts + c = p + ' ' + s + if opts.verbose: print c + if not opts.dryrun: + os.system(c) + +def vif_bridge_add(params): + """Add the network interface for vif on dom to a bridge. + """ + cmd(CMD_BRCTL, 'addif %(bridge)s %(vif)s' % params) + +def vif_bridge_rem(params): + """Remove the network interface for vif on dom from a bridge. + """ + cmd(CMD_BRCTL, 'delif %(bridge)s %(vif)s' % params) + +def vif_restrict_addr(vif, addr, delete=0): + d = { 'vif': vif, 'addr': addr} + if delete: + d['flag'] = '-D' + else: + d['flag'] = '-A' + cmd(CMD_IPTABLES, '-P FORWARD DROP') + cmd(CMD_IPTABLES, '%(flag)s FORWARD -m physdev --physdev-in %(vif)s -s %(addr)s -j ACCEPT' % d) + cmd(CMD_IPTABLES, '%(flag)s FORWARD -m physdev --physdev-out %(vif)s -d %(addr)s -j ACCEPT' % d) + +def bridge_create(bridge, **kwd): + """Create a bridge. + Defaults hello time to 0, forward delay to 0 and stp off. + """ + cmd(CMD_BRCTL, 'addbr %s' % bridge) + if kwd.get('hello', None) is None: + kwd['hello'] = 0 + if kwd.get('fd', None) is None: + kwd['fd'] = 0 + if kwd.get('stp', None) is None: + kwd['stp'] = 'off' + bridge_set(bridge, **kwd) + +def bridge_set(bridge, hello=None, fd=None, stp=None): + """Set bridge parameters. + """ + if hello is not None: + cmd(CMD_BRCTL, 'sethello %s %d' % (bridge, hello)) + if fd is not None: + cmd(CMD_BRCTL, 'setfd %s %d' % (bridge, fd)) + if stp is not None: + cmd(CMD_BRCTL, 'stp %s %s' % (bridge, stp)) + +def bridge_del(bridge): + """Delete a bridge. + """ + cmd(CMD_BRCTL, 'delbr %s' % bridge) + +def routes(): + """Return a list of the routes. + """ + fin = os.popen(CMD_ROUTE + ' -n', 'r') + routes = [] + for x in fin: + if x.startswith('Kernel'): continue + if x.startswith('Destination'): continue + x = x.strip() + y = x.split() + z = { 'destination': y[0], + 'gateway' : y[1], + 'mask' : y[2], + 'flags' : y[3], + 'metric' : y[4], + 'ref' : y[5], + 'use' : y[6], + 'interface' : y[7] } + routes.append(z) + return routes + +def ifconfig(interface): + """Return the ip config for an interface, + """ + fin = os.popen(CMD_IFCONFIG + ' %s' % interface, 'r') + inetre = re.compile('\s*inet\s*addr:(?P<address>\S*)\s*Bcast:(?P<broadcast>\S*)\s*Mask:(?P<mask>\S*)') + info = None + for x in fin: + m = inetre.match(x) + if not m: continue + info = m.groupdict() + info['interface'] = interface + break + return info + +def reconfigure(interface, bridge): + """Reconfigure an interface to be attached to a bridge, and give the bridge + the IP address etc. from interface. Move the default route to the interface + to the bridge. + + """ + global opts + intf_info = ifconfig(interface) + if not intf_info: + print >>sys.stderr, 'Interface not found:', interface + return + #bridge_info = ifconfig(bridge) + #if not bridge_info: + # print >>sys.stderr, 'Bridge not found:', bridge + # return + route_info = routes() + intf_info['bridge'] = bridge + intf_info['gateway'] = None + for r in route_info: + if (r['destination'] == '0.0.0.0' and + 'G' in r['flags'] and + r['interface'] == interface): + intf_info['gateway'] = r['gateway'] + if not intf_info['gateway']: + print >>sys.stderr, 'Gateway not found: ', interface + return + cmd(CMD_IFCONFIG, + '%(bridge)s %(address)s netmask %(mask)s broadcast %(broadcast)s up' + % intf_info) + cmd(CMD_ROUTE, + 'add default gateway %(gateway)s dev %(bridge)s' + % intf_info) + cmd(CMD_BRCTL, 'addif %(bridge)s %(interface)s' % intf_info) + cmd(CMD_IFCONFIG, '%(interface)s 0.0.0.0' % intf_info) + +defaults = { + 'verbose' : 1, + 'dryrun' : 0, + } + +opts = Opts(defaults) + +def set_opts(val): + global opts + opts = val + return opts |