1/*
2 * Copyright (c) 2000-2004 Apple Computer, Inc. All Rights Reserved.
3 *
4 * @APPLE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. Please obtain a copy of the License at
10 * http://www.opensource.apple.com/apsl/ and read it before using this
11 * file.
12 *
13 * The Original Code and all software distributed under the License are
14 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
15 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
16 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
18 * Please see the License for the specific language governing rights and
19 * limitations under the License.
20 *
21 * @APPLE_LICENSE_HEADER_END@
22 */
23
24
25//
26// socks++int - internal Socks implementation
27//
28#include "socks++4.h"
29#include "hosts.h"
30#include <set>
31
32
33namespace Security {
34namespace IPPlusPlus {
35namespace Socks4 {
36
37
38
39//
40// Socks4 Protocol implementation
41//
42void Server::connect(SocksClientSocket &me, const IPSockAddress &peer)
43{
44    me.Socket::open(SOCK_STREAM);
45    me.Socket::connect(mServerAddress);
46    Message request(socksConnect, peer);
47    request.send(me, "nobody");
48    (Message(me));				// read and check reply message
49    me.mPeerAddress = peer;		// best guess, Mr. Sulu
50    secdebug("socks", "%d socks4 connected to %s", me.fd(), string(peer).c_str());
51}
52
53void Server::connect(SocksClientSocket &me, const Host &host, IPPort port)
54{
55    // Socks4 has no name resolution support. Do it here
56    //@@@ error reporting sucks here
57    set<IPAddress> addrs = host.addresses();
58    for (set<IPAddress>::const_iterator it = addrs.begin(); it != addrs.end(); it++) {
59        try {
60            IPSockAddress addr(*it, port);
61            connect(me, addr);
62            return;
63        } catch (const UnixError &err) {
64            errno = err.error;
65        }
66    }
67    // exhausted
68    UnixError::throwMe();
69}
70
71
72void Server::bind(SocksServerSocket &me, const IPAddress &peer, IPPort port)
73{
74    me.Socket::open(SOCK_STREAM);
75    me.Socket::connect(mServerAddress);
76    Message request(socksBind, IPSockAddress(peer, port));
77    request.send(me, "nobody");
78    Message reply(me);
79    me.mLocalAddress = reply.address().defaults(mServerAddress.address());
80    secdebug("socks", "%d socks4 bound to %s", me.fd(), string(me.mLocalAddress).c_str());
81}
82
83void Server::receive(SocksServerSocket &me, SocksClientSocket &receiver)
84{
85    Message reply(me);
86    receiver.setFd(me.fd(), me.mLocalAddress, reply.address());
87    me.clear();					// clear our own (don't close on destruction)
88    secdebug("socks", "%d socks4 inbound connect", receiver.fd());
89}
90
91
92//
93// Message properties
94//
95Message::Message(Command cmd, const IPSockAddress &address)
96    : version(4), message(cmd), port(htons(address.port())), addr(address.address())
97{
98}
99
100
101void Message::send(Socket &s, const char *userid)
102{
103    if (s.write(this, sizeof(*this)) != sizeof(*this))
104        UnixError::throwMe();
105    // now append zero-terminated userid (what a crock)
106    size_t length = strlen(userid) + 1;
107    if (s.write(userid, length) != length) {
108        s.close();
109        UnixError::throwMe();
110    }
111}
112
113Message::Message(Socket &s)
114{
115    if (s.read(this, sizeof(*this)) != sizeof(*this)) {
116        s.close();
117        UnixError::throwMe();
118    }
119    if (version != 0) {
120        s.close();
121        UnixError::throwMe(EPROTONOSUPPORT);
122    }
123    switch (message) {
124    case requestAccepted:
125        return;
126    default:
127        UnixError::throwMe(ECONNREFUSED);	//@@@ hardly any diagnostics here
128    }
129}
130
131
132}	// end namespace Socks
133}	// end namespace IPPlusPlus
134}	// end namespace Security
135