BadVPN – Blame information for rev 1

Subversion Repositories:
Rev:
Rev Author Line No. Line
1 office 1 /**
2 * @file BSocksClient.h
3 * @author Ambroz Bizjak <ambrop7@gmail.com>
4 *
5 * @section LICENSE
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * 3. Neither the name of the author nor the
15 * names of its contributors may be used to endorse or promote products
16 * derived from this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
20 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
21 * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
22 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
23 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
24 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
25 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
27 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 *
29 * @section DESCRIPTION
30 *
31 * SOCKS5 client. TCP only, no authentication.
32 */
33  
34 #ifndef BADVPN_SOCKS_BSOCKSCLIENT_H
35 #define BADVPN_SOCKS_BSOCKSCLIENT_H
36  
37 #include <stddef.h>
38 #include <stdint.h>
39 #include <stdbool.h>
40  
41 #include <misc/debug.h>
42 #include <misc/debugerror.h>
43 #include <misc/socks_proto.h>
44 #include <misc/packed.h>
45 #include <base/DebugObject.h>
46 #include <base/BPending.h>
47 #include <system/BConnection.h>
48 #include <flow/PacketStreamSender.h>
49  
50 #define BSOCKSCLIENT_EVENT_ERROR 1
51 #define BSOCKSCLIENT_EVENT_UP 2
52 #define BSOCKSCLIENT_EVENT_ERROR_CLOSED 3
53 #define BSOCKSCLIENT_EVENT_CONNECTED 4
54  
55 /**
56 * Handler for events generated by the SOCKS client.
57 *
58 * The event is one of the following:
59 * - BSOCKSCLIENT_EVENT_ERROR: An error has occured. The object must be freed from the
60 * job closure of the handler and no further I/O must be attempted.
61 * - BSOCKSCLIENT_EVENT_ERROR_CLOSED: The server has closed the connection. This event
62 * can only be reported after BSOCKSCLIENT_EVENT_UP. The object must be freed from
63 * the job closure of the handler and no further I/O must be attempted.
64 * - BSOCKSCLIENT_EVENT_UP: The CONNECT or UDP ASSOCIATE operation was successful. In
65 * the case of CONNECT, application I/O may now begin.
66 * - BSOCKSCLIENT_EVENT_CONNECTED: The TCP connection to the server has been established
67 * and the SOCKS protocol is about to begin. The local address of the TCP connection is
68 * now available via @ref BSocksClient_GetLocalAddr. The job closure of this callback
69 * is the last chance to call @ref BSocksClient_SetDestAddr.
70 *
71 * @param user as in {@link BSocksClient_Init}
72 * @param event See above.
73 */
74 typedef void (*BSocksClient_handler) (void *user, int event);
75  
76 struct BSocksClient_auth_info {
77 int auth_type;
78 union {
79 struct {
80 const char *username;
81 size_t username_len;
82 const char *password;
83 size_t password_len;
84 } password;
85 };
86 };
87  
88 typedef struct {
89 const struct BSocksClient_auth_info *auth_info;
90 size_t num_auth_info;
91 BAddr dest_addr;
92 bool udp;
93 BAddr bind_addr;
94 BSocksClient_handler handler;
95 void *user;
96 BReactor *reactor;
97 int state;
98 char *buffer;
99 BConnector connector;
100 BConnection con;
101 BPending continue_job;
102 union {
103 struct {
104 PacketPassInterface *send_if;
105 PacketStreamSender send_sender;
106 StreamRecvInterface *recv_if;
107 uint8_t *recv_dest;
108 int recv_len;
109 int recv_total;
110 } control;
111 };
112 DebugError d_err;
113 DebugObject d_obj;
114 } BSocksClient;
115  
116 struct BSocksClient_auth_info BSocksClient_auth_none (void);
117 struct BSocksClient_auth_info BSocksClient_auth_password (const char *username, size_t username_len, const char *password, size_t password_len);
118  
119 /**
120 * Initializes the object.
121 *
122 * This object connects to a SOCKS5 server and performs a CONNECT or UDP ASSOCIATE
123 * operation. In any case, the object reports the BSOCKSCLIENT_EVENT_UP event via the
124 * handler when the operation was completed successfully. In the case of CONNECT, the
125 * user may then use the send and receive interfaces to exchange data through the
126 * connection (@ref BSocksClient_GetSendInterface and @ref BSocksClient_GetRecvInterface).
127 *
128 * @param o the object
129 * @param server_addr SOCKS5 server address
130 * @param auth_info List of supported authentication methods and associated parameters.
131 * Initialize these using functions such as BSocksClient_auth_none() and
132 * BSocksClient_auth_password(). The pointer must remain valid while this object
133 * exists, the data is not copied.
134 * @param num_auth_info Number of the above. There should be at least one, otherwise it
135 * certainly won't work.
136 * @param dest_addr Address to send as DST.ADDR in the CONNECT or UDP ASSOCIATE request.
137 * It is also possible to specify it later from the BSOCKSCLIENT_EVENT_CONNECTED
138 * event callback using @ref BSocksClient_SetDestAddr; this is necessary for UDP
139 * if the local TCP connection address must be known to bind the UDP socket.
140 * @param udp false to perform a CONNECT, true to perform a UDP ASSOCIATE
141 * @param handler handler for up and error events
142 * @param user value passed to handler
143 * @param reactor reactor we live in
144 * @return 1 on success, 0 on failure
145 */
146 int BSocksClient_Init (BSocksClient *o, BAddr server_addr,
147 const struct BSocksClient_auth_info *auth_info, size_t num_auth_info, BAddr dest_addr,
148 bool udp, BSocksClient_handler handler, void *user, BReactor *reactor) WARN_UNUSED;
149  
150 /**
151 * Frees the object.
152 *
153 * @param o the object
154 */
155 void BSocksClient_Free (BSocksClient *o);
156  
157 /**
158 * Get the local address of the TCP socket for the SOCKS server connection.
159 *
160 * This may only be called after the BSOCKSCLIENT_EVENT_CONNECTED event was reported.
161 *
162 * @param o the object
163 * @param local_addr On success the local address is returned here.
164 * @return 1 on success, 0 on failure
165 */
166 int BSocksClient_GetLocalAddr (BSocksClient *o, BAddr *local_addr);
167  
168 /**
169 * Set the DST.ADDR to send, overriding that specified in @ref BSocksClient_Init.
170 *
171 * The last chance to call this function is in the job closure of the
172 * BSOCKSCLIENT_EVENT_CONNECTED event, this must not be called after that.
173 *
174 * @param o the object
175 * @param dest_addr DST.ADDR to set.
176 */
177 void BSocksClient_SetDestAddr (BSocksClient *o, BAddr dest_addr);
178  
179 /**
180 * Return the BND.ADDR that the SOCKS server reported.
181 *
182 * This may only be called after the BSOCKSCLIENT_EVENT_UP event was reported.
183 * This address is needed for UDP ASSOCIATE because it is the address that the
184 * client should send UDP packets to.
185 *
186 * @param o the object
187 * @return The BND.ADDR, of type BADDR_TYPE_IPV4 or BADDR_TYPE_IPV6.
188 */
189 BAddr BSocksClient_GetBindAddr (BSocksClient *o);
190  
191 /**
192 * Returns the send interface.
193 * The object must be in up state. Additionally this must not be called if the
194 * object was initialized in UDP ASSOCIATE mode.
195 *
196 * @param o the object
197 * @return send interface
198 */
199 StreamPassInterface * BSocksClient_GetSendInterface (BSocksClient *o);
200  
201 /**
202 * Returns the receive interface.
203 * The object must be in up state. Additionally this must not be called if the
204 * object was initialized in UDP ASSOCIATE mode.
205 *
206 * @param o the object
207 * @return receive interface
208 */
209 StreamRecvInterface * BSocksClient_GetRecvInterface (BSocksClient *o);
210  
211 #endif