| 1 | """RPC Server module."""
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| 2 |
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| 3 | import sys
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| 4 | import socket
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| 5 | import pickle
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| 6 | from fnmatch import fnmatch
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| 7 | from repr import repr
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| 8 |
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| 9 |
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| 10 | # Default verbosity (0 = silent, 1 = print connections, 2 = print requests too)
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| 11 | VERBOSE = 1
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| 12 |
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| 13 |
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| 14 | class Server:
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| 15 |
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| 16 | """RPC Server class. Derive a class to implement a particular service."""
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| 17 |
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| 18 | def __init__(self, address, verbose = VERBOSE):
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| 19 | if type(address) == type(0):
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| 20 | address = ('', address)
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| 21 | self._address = address
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| 22 | self._verbose = verbose
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| 23 | self._socket = None
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| 24 | self._socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
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| 25 | self._socket.bind(address)
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| 26 | self._socket.listen(1)
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| 27 | self._listening = 1
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| 28 |
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| 29 | def _setverbose(self, verbose):
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| 30 | self._verbose = verbose
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| 31 |
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| 32 | def __del__(self):
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| 33 | self._close()
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| 34 |
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| 35 | def _close(self):
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| 36 | self._listening = 0
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| 37 | if self._socket:
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| 38 | self._socket.close()
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| 39 | self._socket = None
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| 40 |
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| 41 | def _serverloop(self):
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| 42 | while self._listening:
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| 43 | self._serve()
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| 44 |
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| 45 | def _serve(self):
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| 46 | if self._verbose: print "Wait for connection ..."
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| 47 | conn, address = self._socket.accept()
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| 48 | if self._verbose: print "Accepted connection from %s" % repr(address)
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| 49 | if not self._verify(conn, address):
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| 50 | print "*** Connection from %s refused" % repr(address)
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| 51 | conn.close()
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| 52 | return
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| 53 | rf = conn.makefile('r')
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| 54 | wf = conn.makefile('w')
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| 55 | ok = 1
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| 56 | while ok:
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| 57 | wf.flush()
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| 58 | if self._verbose > 1: print "Wait for next request ..."
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| 59 | ok = self._dorequest(rf, wf)
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| 60 |
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| 61 | _valid = ['192.16.201.*', '192.16.197.*', '132.151.1.*', '129.6.64.*']
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| 62 |
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| 63 | def _verify(self, conn, address):
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| 64 | host, port = address
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| 65 | for pat in self._valid:
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| 66 | if fnmatch(host, pat): return 1
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| 67 | return 0
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| 68 |
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| 69 | def _dorequest(self, rf, wf):
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| 70 | rp = pickle.Unpickler(rf)
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| 71 | try:
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| 72 | request = rp.load()
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| 73 | except EOFError:
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| 74 | return 0
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| 75 | if self._verbose > 1: print "Got request: %s" % repr(request)
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| 76 | try:
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| 77 | methodname, args, id = request
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| 78 | if '.' in methodname:
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| 79 | reply = (None, self._special(methodname, args), id)
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| 80 | elif methodname[0] == '_':
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| 81 | raise NameError, "illegal method name %s" % repr(methodname)
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| 82 | else:
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| 83 | method = getattr(self, methodname)
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| 84 | reply = (None, apply(method, args), id)
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| 85 | except:
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| 86 | reply = (sys.exc_type, sys.exc_value, id)
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| 87 | if id < 0 and reply[:2] == (None, None):
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| 88 | if self._verbose > 1: print "Suppress reply"
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| 89 | return 1
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| 90 | if self._verbose > 1: print "Send reply: %s" % repr(reply)
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| 91 | wp = pickle.Pickler(wf)
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| 92 | wp.dump(reply)
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| 93 | return 1
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| 94 |
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| 95 | def _special(self, methodname, args):
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| 96 | if methodname == '.methods':
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| 97 | if not hasattr(self, '_methods'):
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| 98 | self._methods = tuple(self._listmethods())
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| 99 | return self._methods
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| 100 | raise NameError, "unrecognized special method name %s" % repr(methodname)
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| 101 |
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| 102 | def _listmethods(self, cl=None):
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| 103 | if not cl: cl = self.__class__
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| 104 | names = cl.__dict__.keys()
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| 105 | names = filter(lambda x: x[0] != '_', names)
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| 106 | names.sort()
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| 107 | for base in cl.__bases__:
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| 108 | basenames = self._listmethods(base)
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| 109 | basenames = filter(lambda x, names=names: x not in names, basenames)
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| 110 | names[len(names):] = basenames
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| 111 | return names
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| 112 |
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| 113 |
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| 114 | from security import Security
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| 115 |
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| 116 |
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| 117 | class SecureServer(Server, Security):
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| 118 |
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| 119 | def __init__(self, *args):
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| 120 | apply(Server.__init__, (self,) + args)
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| 121 | Security.__init__(self)
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| 122 |
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| 123 | def _verify(self, conn, address):
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| 124 | import string
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| 125 | challenge = self._generate_challenge()
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| 126 | conn.send("%d\n" % challenge)
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| 127 | response = ""
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| 128 | while "\n" not in response and len(response) < 100:
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| 129 | data = conn.recv(100)
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| 130 | if not data:
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| 131 | break
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| 132 | response = response + data
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| 133 | try:
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| 134 | response = string.atol(string.strip(response))
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| 135 | except string.atol_error:
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| 136 | if self._verbose > 0:
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| 137 | print "Invalid response syntax", repr(response)
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| 138 | return 0
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| 139 | if not self._compare_challenge_response(challenge, response):
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| 140 | if self._verbose > 0:
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| 141 | print "Invalid response value", repr(response)
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| 142 | return 0
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| 143 | if self._verbose > 1:
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| 144 | print "Response matches challenge. Go ahead!"
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| 145 | return 1
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