contrib/client-tools/tor-resolve.py

   1 #!/usr/bin/env python
   2
   3 # Future imports for Python 2.7, mandatory in 3.0
   4 from __future__ import division
   5 from __future__ import print_function
   6 from __future__ import unicode_literals
   7
   8 import socket
   9 import struct
  10 import sys
  11
  12 def socks4AResolveRequest(hostname):
  13     version = 4
  14     command = 0xF0
  15     port = 0
  16     addr = 0x0000001
  17     username = ""
  18     reqheader = struct.pack("!BBHL", version, command, port, addr)
  19     return "%s%s\x00%s\x00"%(reqheader,username,hostname)
  20
  21 def socks4AParseResponse(response):
  22     RESPONSE_LEN = 8
  23     if len(response) < RESPONSE_LEN:
  24         return None
  25     assert len(response) >= RESPONSE_LEN
  26     version,status,port = struct.unpack("!BBH",response[:4])
  27     assert version == 0
  28     assert port == 0
  29     if status == 90:
  30         return "%d.%d.%d.%d"%tuple(map(ord, response[4:]))
  31     else:
  32         return "ERROR (status %d)"%status
  33
  34 def socks5Hello():
  35     return "\x05\x01\x00"
  36 def socks5ParseHello(response):
  37     if response != "\x05\x00":
  38         raise ValueError("Bizarre socks5 response")
  39 def socks5ResolveRequest(hostname, atype=0x03, command=0xF0):
  40     version = 5
  41     rsv = 0
  42     port = 0
  43     reqheader = struct.pack("!BBBB",version, command, rsv, atype)
  44     if atype == 0x03:
  45         reqheader += struct.pack("!B", len(hostname))
  46     portstr = struct.pack("!H",port)
  47     return "%s%s%s"%(reqheader,hostname,portstr)
  48
  49 def socks5ParseResponse(r):
  50     if len(r)<8:
  51         return None
  52     version, reply, rsv, atype = struct.unpack("!BBBB",r[:4])
  53     assert version==5
  54     assert rsv==0
  55     if reply != 0x00:
  56         return "ERROR",reply
  57     assert atype in (0x01,0x03,0x04)
  58     if atype != 0x03:
  59         expected_len = 4 + ({1:4,4:16}[atype]) + 2
  60         if len(r) < expected_len:
  61             return None
  62         elif len(r) > expected_len:
  63             raise ValueError("Overlong socks5 reply!")
  64         addr = r[4:-2]
  65         if atype == 0x01:
  66             return "%d.%d.%d.%d"%tuple(map(ord,addr))
  67         else:
  68             # not really the right way to format IPv6
  69             return "IPv6: %s"%(":".join([hex(ord(c)) for c in addr]))
  70     else:
  71         hlen, = struct.unpack("!B", r[4])
  72         expected_len = 5 + hlen + 2
  73         if len(r) < expected_len:
  74             return None
  75         return r[5:-2]
  76
  77 def socks5ResolvePTRRequest(hostname):
  78     return socks5ResolveRequest(socket.inet_aton(hostname),
  79                                 atype=1, command = 0xF1)
  80
  81
  82 def parseHostAndPort(h):
  83     host, port = "localhost", 9050
  84     if ":" in h:
  85         i = h.index(":")
  86         host = h[:i]
  87         try:
  88             port = int(h[i+1:])
  89         except ValueError:
  90             print("Bad hostname %r"%h)
  91             sys.exit(1)
  92     elif h:
  93         try:
  94             port = int(h)
  95         except ValueError:
  96             host = h
  97
  98     return host, port
  99
 100 def resolve(hostname, sockshost, socksport, socksver=4, reverse=0):
 101     assert socksver in (4,5)
 102     if socksver == 4:
 103         fmt = socks4AResolveRequest
 104         parse = socks4AParseResponse
 105     elif not reverse:
 106         fmt = socks5ResolveRequest
 107         parse = socks5ParseResponse
 108     else:
 109         fmt = socks5ResolvePTRRequest
 110         parse = socks5ParseResponse
 111
 112     s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
 113     s.connect((sockshost,socksport))
 114     if socksver == 5:
 115         s.send(socks5Hello())
 116         socks5ParseHello(s.recv(2))
 117     s.send(fmt(hostname))
 118     answer = s.recv(6)
 119     result = parse(answer)
 120     while result is None:
 121         more = s.recv(1)
 122         if not more:
 123             return None
 124         answer += more
 125         result = parse(answer)
 126     print("Got answer",result)
 127     m = s.recv(1)
 128     if m:
 129         print("Got extra data too: %r"%m)
 130     return result
 131
 132 if __name__ == '__main__':
 133     if len(sys.argv) not in (2,3,4):
 134         print("Syntax: resolve.py [-4|-5] hostname [sockshost:socksport]")
 135         sys.exit(0)
 136     socksver = 4
 137     reverse = 0
 138     while sys.argv[1][0] == '-':
 139         if sys.argv[1] in ("-4", "-5"):
 140             socksver = int(sys.argv[1][1])
 141             del sys.argv[1]
 142         elif sys.argv[1] == '-x':
 143             reverse = 1
 144             del sys.argv[1]
 145         elif sys.argv[1] == '--':
 146             break
 147
 148     if len(sys.argv) >= 4:
 149         print("Syntax: resolve.py [-x] [-4|-5] hostname [sockshost:socksport]")
 150         sys.exit(0)
 151     if len(sys.argv) == 3:
 152         sh,sp = parseHostAndPort(sys.argv[2])
 153     else:
 154         sh,sp = parseHostAndPort("")
 155
 156     if reverse and socksver == 4:
 157         socksver = 5
 158     resolve(sys.argv[1], sh, sp, socksver, reverse)