cdsa/cdsa_utilities/socks++4.cpp

   1 /*
   2  * Copyright (c) 2000-2001 Apple Computer, Inc. All Rights Reserved.
   3  *
   4  * The contents of this file constitute Original Code as defined in and are
   5  * subject to the Apple Public Source License Version 1.2 (the 'License').
   6  * You may not use this file except in compliance with the License. Please obtain
   7  * a copy of the License at http://www.apple.com/publicsource and read it before
   8  * using this file.
   9  *
  10  * This Original Code and all software distributed under the License are
  11  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESS
  12  * OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, INCLUDING WITHOUT
  13  * LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
  14  * PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. Please see the License for the
  15  * specific language governing rights and limitations under the License.
  16  */
  17
  18
  19 //
  20 // socks++int - internal Socks implementation
  21 //
  22 #include "socks++4.h"
  23 #include "hosts.h"
  24 #include <set>
  25
  26
  27 namespace Security {
  28 namespace IPPlusPlus {
  29 namespace Socks4 {
  30
  31
  32
  33 //
  34 // Socks4 Protocol implementation
  35 //
  36 void Server::connect(SocksClientSocket &me, const IPSockAddress &peer)
  37 {
  38     me.Socket::open(SOCK_STREAM);
  39     me.Socket::connect(mServerAddress);
  40     Message request(socksConnect, peer);
  41     request.send(me, "nobody");
  42     (Message(me));                              // read and check reply message
  43     me.mPeerAddress = peer;             // best guess, Mr. Sulu
  44     debug("socks", "%d socks4 connected to %s", me.fd(), string(peer).c_str());
  45 }
  46
  47 void Server::connect(SocksClientSocket &me, const Host &host, IPPort port)
  48 {
  49     // Socks4 has no name resolution support. Do it here
  50     //@@@ error reporting sucks here
  51     set<IPAddress> addrs = host.addresses();
  52     for (set<IPAddress>::const_iterator it = addrs.begin(); it != addrs.end(); it++) {
  53         try {
  54             IPSockAddress addr(*it, port);
  55             connect(me, addr);
  56             return;
  57         } catch (const UnixError &err) {
  58             errno = err.error;
  59         }
  60     }
  61     // exhausted
  62     UnixError::throwMe();
  63 }
  64
  65
  66 void Server::bind(SocksServerSocket &me, const IPAddress &peer, IPPort port)
  67 {
  68     me.Socket::open(SOCK_STREAM);
  69     me.Socket::connect(mServerAddress);
  70     Message request(socksBind, IPSockAddress(peer, port));
  71     request.send(me, "nobody");
  72     Message reply(me);
  73     me.mLocalAddress = reply.address().defaults(mServerAddress.address());
  74     debug("socks", "%d socks4 bound to %s", me.fd(), string(me.mLocalAddress).c_str());
  75 }
  76
  77 void Server::receive(SocksServerSocket &me, SocksClientSocket &receiver)
  78 {
  79     Message reply(me);
  80     receiver.setFd(me.fd(), me.mLocalAddress, reply.address());
  81     me.clear();                                 // clear our own (don't close on destruction)
  82     debug("socks", "%d socks4 inbound connect", receiver.fd());
  83 }
  84
  85
  86 //
  87 // Message properties
  88 //
  89 Message::Message(Command cmd, const IPSockAddress &address)
  90     : version(4), message(cmd), port(htons(address.port())), addr(address.address())
  91 {
  92 }
  93
  94
  95 void Message::send(Socket &s, const char *userid)
  96 {
  97     if (s.write(this, sizeof(*this)) != sizeof(*this))
  98         UnixError::throwMe();
  99     // now append zero-terminated userid (what a crock)
 100     size_t length = strlen(userid) + 1;
 101     if (s.write(userid, length) != length) {
 102         s.close();
 103         UnixError::throwMe();
 104     }
 105 }
 106
 107 Message::Message(Socket &s)
 108 {
 109     if (s.read(this, sizeof(*this)) != sizeof(*this)) {
 110         s.close();
 111         UnixError::throwMe();
 112     }
 113     if (version != 0) {
 114         s.close();
 115         UnixError::throwMe(EPROTONOSUPPORT);
 116     }
 117     switch (message) {
 118     case requestAccepted:
 119         return;
 120     default:
 121         UnixError::throwMe(ECONNREFUSED);       //@@@ hardly any diagnostics here
 122     }
 123 }
 124
 125
 126 }       // end namespace Socks
 127 }       // end namespace IPPlusPlus
 128 }       // end namespace Security