1 # portions extracted from ipaddresslib by Autonomous Zone Industries, LGPL (author: Greg Smith)
2 # portions adapted from nattraverso.ipdiscover
3 # portions authored by Brian Warner, working for Allmydata
4 # most recent version authored by Zooko O'Whielacronx, working for Allmydata
6 # from the Python Standard Library
7 import os, re, socket, sys
10 from twisted.internet import defer
11 from twisted.internet import reactor
12 from twisted.internet.protocol import DatagramProtocol
13 from twisted.internet.utils import getProcessOutput
14 from twisted.python.procutils import which
15 from twisted.python import log
22 def increase_rlimits():
23 # We'd like to raise our soft resource.RLIMIT_NOFILE, since certain
24 # systems (OS-X, probably solaris) start with a relatively low limit
25 # (256), and some unit tests want to open up more sockets than this.
26 # Most linux systems start with both hard and soft limits at 1024,
29 # unfortunately the values to pass to setrlimit() vary widely from
30 # one system to another. OS-X reports (256, HUGE), but the real hard
31 # limit is 10240, and accepts (-1,-1) to mean raise it to the
32 # maximum. Cygwin reports (256, -1), then ignores a request of
33 # (-1,-1): instead you have to guess at the hard limit (it appears to
34 # be 3200), so using (3200,-1) seems to work. Linux reports a
35 # sensible (1024,1024), then rejects (-1,-1) as trying to raise the
36 # maximum limit, so you could set it to (1024,1024) but you might as
37 # well leave it alone.
40 current = resource.getrlimit(resource.RLIMIT_NOFILE)
41 except AttributeError:
42 # we're probably missing RLIMIT_NOFILE
45 if current[0] >= 1024:
46 # good enough, leave it alone
50 if current[1] > 0 and current[1] < 1000000:
51 # solaris reports (256, 65536)
52 resource.setrlimit(resource.RLIMIT_NOFILE,
53 (current[1], current[1]))
55 # this one works on OS-X (bsd), and gives us 10240, but
56 # it doesn't work on linux (on which both the hard and
57 # soft limits are set to 1024 by default).
58 resource.setrlimit(resource.RLIMIT_NOFILE, (-1,-1))
59 new = resource.getrlimit(resource.RLIMIT_NOFILE)
60 if new[0] == current[0]:
61 # probably cygwin, which ignores -1. Use a real value.
62 resource.setrlimit(resource.RLIMIT_NOFILE, (3200,-1))
65 log.msg("unable to set RLIMIT_NOFILE: current value %s"
66 % (resource.getrlimit(resource.RLIMIT_NOFILE),))
68 # who knows what. It isn't very important, so log it and continue
71 def _increase_rlimits():
72 # TODO: implement this for Windows. Although I suspect the
73 # solution might be "be running under the iocp reactor and
74 # make this function be a no-op".
76 # pyflakes complains about two 'def FOO' statements in the same time,
77 # since one might be shadowing the other. This hack appeases pyflakes.
78 increase_rlimits = _increase_rlimits
81 def get_local_addresses_async(target="198.41.0.4"): # A.ROOT-SERVERS.NET
83 Return a Deferred that fires with a list of IPv4 addresses (as dotted-quad
84 strings) that are currently configured on this host, sorted in descending
85 order of how likely we think they are to work.
87 @param target: we want to learn an IP address they could try using to
88 connect to us; The default value is fine, but it might help if you
89 pass the address of a host that you are actually trying to be
93 local_ip = get_local_ip_for(target)
95 addresses.append(local_ip)
97 if sys.platform == "cygwin":
98 d = _cygwin_hack_find_addresses(target)
100 d = _find_addresses_via_config()
104 if addr != "0.0.0.0" and not addr in addresses:
105 addresses.append(addr)
107 d.addCallback(_collect)
111 def get_local_ip_for(target):
112 """Find out what our IP address is for use by a given target.
114 @return: the IP address as a dotted-quad string which could be used by
115 to connect to us. It might work for them, it might not. If
116 there is no suitable address (perhaps we don't currently have an
117 externally-visible interface), this will return None.
121 target_ipaddr = socket.gethostbyname(target)
122 except socket.gaierror:
123 # DNS isn't running, or somehow we encountered an error
125 # note: if an interface is configured and up, but nothing is
126 # connected to it, gethostbyname("A.ROOT-SERVERS.NET") will take 20
127 # seconds to raise socket.gaierror . This is synchronous and occurs
128 # for each node being started, so users of
129 # test.common.SystemTestMixin (like test_system) will see something
130 # like 120s of delay, which may be enough to hit the default trial
131 # timeouts. For that reason, get_local_addresses_async() was changed
132 # to default to the numerical ip address for A.ROOT-SERVERS.NET, to
133 # avoid this DNS lookup. This also makes node startup fractionally
136 udpprot = DatagramProtocol()
137 port = reactor.listenUDP(0, udpprot)
139 udpprot.transport.connect(target_ipaddr, 7)
140 localip = udpprot.transport.getHost().host
142 # no route to that host
144 port.stopListening() # note, this returns a Deferred
147 # k: result of sys.platform, v: which kind of IP configuration reader we use
149 "linux-i386": "linux", # redhat
150 "linux-ppc": "linux", # redhat
151 "linux2": "linux", # debian
157 "darwin": "bsd", # Mac OS X
171 class UnsupportedPlatformError(Exception):
174 # Wow, I'm really amazed at home much mileage we've gotten out of calling
175 # the external route.exe program on windows... It appears to work on all
176 # versions so far. Still, the real system calls would much be preferred...
177 # ... thus wrote Greg Smith in time immemorial...
178 _win32_path = 'route.exe'
179 _win32_args = ('print',)
180 _win32_re = re.compile('^\s*\d+\.\d+\.\d+\.\d+\s.+\s(?P<address>\d+\.\d+\.\d+\.\d+)\s+(?P<metric>\d+)\s*$', flags=re.M|re.I|re.S)
182 # These work in Redhat 6.x and Debian 2.2 potato
183 _linux_path = '/sbin/ifconfig'
184 _linux_re = re.compile('^\s*inet addr:(?P<address>\d+\.\d+\.\d+\.\d+)\s.+$', flags=re.M|re.I|re.S)
186 # NetBSD 1.4 (submitted by Rhialto), Darwin, Mac OS X
187 _netbsd_path = '/sbin/ifconfig'
188 _netbsd_args = ('-a',)
189 _netbsd_re = re.compile('^\s+inet (?P<address>\d+\.\d+\.\d+\.\d+)\s.+$', flags=re.M|re.I|re.S)
192 _irix_path = '/usr/etc/ifconfig'
195 _sunos_path = '/usr/sbin/ifconfig'
197 class SequentialTrier(object):
198 """ I hold a list of executables to try and try each one in turn
199 until one gives me a list of IP addresses."""
201 def __init__(self, exebasename, args, regex):
202 assert not os.path.isabs(exebasename)
203 self.exes_left_to_try = which(exebasename)
204 self.exes_left_to_try.reverse()
207 self.o = observer.OneShotObserverList()
211 if not self.exes_left_to_try:
214 exe = self.exes_left_to_try.pop()
215 d2 = _query(exe, self.args, self.regex)
226 d2.addCallbacks(cb, eb)
228 def when_tried(self):
229 return self.o.when_fired()
231 # k: platform string as provided in the value of _platform_map
232 # v: tuple of (path_to_tool, args, regex,)
234 "linux": (_linux_path, (), _linux_re,),
235 "win32": (_win32_path, _win32_args, _win32_re,),
236 "cygwin": (_win32_path, _win32_args, _win32_re,),
237 "bsd": (_netbsd_path, _netbsd_args, _netbsd_re,),
238 "irix": (_irix_path, _netbsd_args, _netbsd_re,),
239 "sunos": (_sunos_path, _netbsd_args, _netbsd_re,),
241 def _find_addresses_via_config():
242 # originally by Greg Smith, hacked by Zooko to conform to Brian's API
244 platform = _platform_map.get(sys.platform)
246 raise UnsupportedPlatformError(sys.platform)
248 (pathtotool, args, regex,) = _tool_map[platform]
250 # If pathtotool is a fully qualified path then we just try that.
251 # If it is merely an executable name then we use Twisted's
252 # "which()" utility and try each executable in turn until one
253 # gives us something that resembles a dotted-quad IPv4 address.
255 if os.path.isabs(pathtotool):
256 return _query(pathtotool, args, regex)
258 return SequentialTrier(pathtotool, args, regex).when_tried()
260 def _query(path, args, regex):
261 d = getProcessOutput(path, args)
264 outputsplit = output.split('\n')
265 for outline in outputsplit:
266 m = regex.match(outline)
268 addr = m.groupdict()['address']
269 if addr not in addresses:
270 addresses.append(addr)
273 d.addCallback(_parse)
276 def _cygwin_hack_find_addresses(target):
278 for h in [target, "localhost", "127.0.0.1",]:
280 addr = get_local_ip_for(h)
281 if addr not in addresses:
282 addresses.append(addr)
283 except socket.gaierror:
286 return defer.succeed(addresses)