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='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:
125 udpprot = DatagramProtocol()
126 port = reactor.listenUDP(0, udpprot)
128 udpprot.transport.connect(target_ipaddr, 7)
129 localip = udpprot.transport.getHost().host
131 # no route to that host
133 port.stopListening() # note, this returns a Deferred
136 # k: result of sys.platform, v: which kind of IP configuration reader we use
138 "linux-i386": "linux", # redhat
139 "linux-ppc": "linux", # redhat
140 "linux2": "linux", # debian
146 "darwin": "bsd", # Mac OS X
155 class UnsupportedPlatformError(Exception):
158 # Wow, I'm really amazed at home much mileage we've gotten out of calling
159 # the external route.exe program on windows... It appears to work on all
160 # versions so far. Still, the real system calls would much be preferred...
161 # ... thus wrote Greg Smith in time immemorial...
162 _win32_path = 'route.exe'
163 _win32_args = ('print',)
164 _win32_re = re.compile('^\s*\d+\.\d+\.\d+\.\d+\s.+\s(?P<address>\d+\.\d+\.\d+\.\d+)\s+(?P<metric>\d+)\s*$', flags=re.M|re.I|re.S)
166 # These work in Redhat 6.x and Debian 2.2 potato
167 _linux_path = '/sbin/ifconfig'
168 _linux_re = re.compile('^\s*inet addr:(?P<address>\d+\.\d+\.\d+\.\d+)\s.+$', flags=re.M|re.I|re.S)
170 # NetBSD 1.4 (submitted by Rhialto), Darwin, Mac OS X
171 _netbsd_path = '/sbin/ifconfig'
172 _netbsd_args = ('-a',)
173 _netbsd_re = re.compile('^\s+inet (?P<address>\d+\.\d+\.\d+\.\d+)\s.+$', flags=re.M|re.I|re.S)
176 _irix_path = '/usr/etc/ifconfig'
179 _sunos_path = '/usr/sbin/ifconfig'
181 class SequentialTrier(object):
182 """ I hold a list of executables to try and try each one in turn
183 until one gives me a list of IP addresses."""
185 def __init__(self, exebasename, args, regex):
186 assert not os.path.isabs(exebasename)
187 self.exes_left_to_try = which(exebasename)
188 self.exes_left_to_try.reverse()
191 self.o = observer.OneShotObserverList()
195 if not self.exes_left_to_try:
198 exe = self.exes_left_to_try.pop()
199 d2 = _query(exe, self.args, self.regex)
210 d2.addCallbacks(cb, eb)
212 def when_tried(self):
213 return self.o.when_fired()
215 # k: platform string as provided in the value of _platform_map
216 # v: tuple of (path_to_tool, args, regex,)
218 "linux": (_linux_path, (), _linux_re,),
219 "win32": (_win32_path, _win32_args, _win32_re,),
220 "cygwin": (_win32_path, _win32_args, _win32_re,),
221 "bsd": (_netbsd_path, _netbsd_args, _netbsd_re,),
222 "irix": (_irix_path, _netbsd_args, _netbsd_re,),
223 "sunos": (_sunos_path, _netbsd_args, _netbsd_re,),
225 def _find_addresses_via_config():
226 # originally by Greg Smith, hacked by Zooko to conform to Brian's API
228 platform = _platform_map.get(sys.platform)
230 raise UnsupportedPlatformError(sys.platform)
232 (pathtotool, args, regex,) = _tool_map[platform]
234 # If pathtotool is a fully qualified path then we just try that.
235 # If it is merely an executable name then we use Twisted's
236 # "which()" utility and try each executable in turn until one
237 # gives us something that resembles a dotted-quad IPv4 address.
239 if os.path.isabs(pathtotool):
240 return _query(pathtotool, args, regex)
242 return SequentialTrier(pathtotool, args, regex).when_tried()
244 def _query(path, args, regex):
245 d = getProcessOutput(path, args)
248 outputsplit = output.split('\n')
249 for outline in outputsplit:
250 m = regex.match(outline)
252 addr = m.groupdict()['address']
253 if addr not in addresses:
254 addresses.append(addr)
257 d.addCallback(_parse)
260 def _cygwin_hack_find_addresses(target):
262 for h in [target, "localhost", "127.0.0.1",]:
264 addr = get_local_ip_for(h)
265 if addr not in addresses:
266 addresses.append(addr)
267 except socket.gaierror:
270 return defer.succeed(addresses)