1 /* $Id$ */
2 /*
3  * Copyright (C) 2008-2011 Teluu Inc. (http://www.teluu.com)
4  * Copyright (C) 2003-2008 Benny Prijono <benny@prijono.org>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the Free Software
18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
19  */
20 #ifndef __PJNATH_STUN_SOCK_H__
21 #define __PJNATH_STUN_SOCK_H__
22 
23 /**
24  * @file stun_sock.h
25  * @brief STUN aware socket transport
26  */
27 #include <pjnath/stun_config.h>
28 #include <pjlib-util/resolver.h>
29 #include <pj/ioqueue.h>
30 #include <pj/lock.h>
31 #include <pj/sock.h>
32 #include <pj/sock_qos.h>
33 
34 
35 PJ_BEGIN_DECL
36 
37 
38 /**
39  * @addtogroup PJNATH_STUN_SOCK
40  * @{
41  *
42  * The STUN transport provides asynchronous UDP like socket transport
43  * with the additional STUN capability. It has the following features:
44  *
45  *  - API to send and receive UDP packets
46  *
47  *  - multiplex STUN and non-STUN incoming packets and distinguish between
48  *    STUN responses that belong to internal requests with application data
49  *    (the application data may be STUN packets as well)
50  *
51  *  - DNS SRV resolution to the STUN server (if wanted), along with fallback
52  *    to DNS A resolution if SRV record is not found.
53  *
54  *  - STUN keep-alive maintenance, and handle changes to the mapped address
55  *    (when the NAT binding changes)
56  *
57  */
58 
59 /**
60  * Opaque type to represent a STUN transport.
61  */
62 typedef struct pj_stun_sock pj_stun_sock;
63 
64 /**
65  * Types of operation being reported in \a on_status() callback of
66  * pj_stun_sock_cb. Application may retrieve the string representation
67  * of these constants with pj_stun_sock_op_name().
68  */
69 typedef enum pj_stun_sock_op
70 {
71     /**
72      * Asynchronous DNS resolution.
73      */
74     PJ_STUN_SOCK_DNS_OP		= 1,
75 
76     /**
77      * Initial STUN Binding request.
78      */
79     PJ_STUN_SOCK_BINDING_OP,
80 
81     /**
82      * Subsequent STUN Binding request for keeping the binding
83      * alive.
84      */
85     PJ_STUN_SOCK_KEEP_ALIVE_OP,
86 
87     /**
88      * IP address change notification from the keep-alive operation.
89      */
90     PJ_STUN_SOCK_MAPPED_ADDR_CHANGE
91 
92 
93 } pj_stun_sock_op;
94 
95 
96 /**
97  * This structure contains callbacks that will be called by the STUN
98  * transport to notify application about various events.
99  */
100 typedef struct pj_stun_sock_cb
101 {
102     /**
103      * Notification when incoming packet has been received.
104      *
105      * @param stun_sock	The STUN transport.
106      * @param data	The packet.
107      * @param data_len	Length of the packet.
108      * @param src_addr	The source address of the packet.
109      * @param addr_len	The length of the source address.
110      *
111      * @return		Application should normally return PJ_TRUE to let
112      *			the STUN transport continue its operation. However
113      *			it must return PJ_FALSE if it has destroyed the
114      *			STUN transport in this callback.
115      */
116     pj_bool_t (*on_rx_data)(pj_stun_sock *stun_sock,
117 			    void *pkt,
118 			    unsigned pkt_len,
119 			    const pj_sockaddr_t *src_addr,
120 			    unsigned addr_len);
121 
122     /**
123      * Notifification when asynchronous send operation has completed.
124      *
125      * @param stun_sock	The STUN transport.
126      * @param send_key	The send operation key that was given in
127      *			#pj_stun_sock_sendto().
128      * @param sent	If value is positive non-zero it indicates the
129      *			number of data sent. When the value is negative,
130      *			it contains the error code which can be retrieved
131      *			by negating the value (i.e. status=-sent).
132      *
133      * @return		Application should normally return PJ_TRUE to let
134      *			the STUN transport continue its operation. However
135      *			it must return PJ_FALSE if it has destroyed the
136      *			STUN transport in this callback.
137      */
138     pj_bool_t (*on_data_sent)(pj_stun_sock *stun_sock,
139 			      pj_ioqueue_op_key_t *send_key,
140 			      pj_ssize_t sent);
141 
142     /**
143      * Notification when the status of the STUN transport has changed. This
144      * callback may be called for the following conditions:
145      *	- the first time the publicly mapped address has been resolved from
146      *	  the STUN server, this callback will be called with \a op argument
147      *    set to PJ_STUN_SOCK_BINDING_OP \a status  argument set to
148      *    PJ_SUCCESS.
149      *	- anytime when the transport has detected that the publicly mapped
150      *    address has changed, this callback will be called with \a op
151      *    argument set to PJ_STUN_SOCK_KEEP_ALIVE_OP and \a status
152      *    argument set to PJ_SUCCESS. On this case and the case above,
153      *    application will get the resolved public address in the
154      *    #pj_stun_sock_info structure.
155      *	- for any terminal error (such as STUN time-out, DNS resolution
156      *    failure, or keep-alive failure), this callback will be called
157      *	  with the \a status argument set to non-PJ_SUCCESS.
158      *
159      * @param stun_sock	The STUN transport.
160      * @param op	The operation that triggers the callback.
161      * @param status	The status.
162      *
163      * @return		Must return PJ_FALSE if it has destroyed the
164      *			STUN transport in this callback. Application should
165      *			normally destroy the socket and return PJ_FALSE
166      *			upon encountering terminal error, otherwise it
167      *			should return PJ_TRUE to let the STUN socket operation
168      *			continues.
169      */
170     pj_bool_t	(*on_status)(pj_stun_sock *stun_sock,
171 			     pj_stun_sock_op op,
172 			     pj_status_t status);
173 
174 } pj_stun_sock_cb;
175 
176 
177 /**
178  * This structure contains information about the STUN transport. Application
179  * may query this information by calling #pj_stun_sock_get_info().
180  */
181 typedef struct pj_stun_sock_info
182 {
183     /**
184      * The bound address of the socket.
185      */
186     pj_sockaddr	    bound_addr;
187 
188     /**
189      * IP address of the STUN server.
190      */
191     pj_sockaddr	    srv_addr;
192 
193     /**
194      * The publicly mapped address. It may contain zero address when the
195      * mapped address has not been resolved. Application may query whether
196      * this field contains valid address with pj_sockaddr_has_addr().
197      */
198     pj_sockaddr	    mapped_addr;
199 
200     /**
201      * Number of interface address aliases. The interface address aliases
202      * are list of all interface addresses in this host.
203      */
204     unsigned	    alias_cnt;
205 
206     /**
207      * Array of interface address aliases.
208      */
209     pj_sockaddr	    aliases[PJ_ICE_ST_MAX_CAND];
210 
211 } pj_stun_sock_info;
212 
213 
214 /**
215  * This describe the settings to be given to the STUN transport during its
216  * creation. Application should initialize this structure by calling
217  * #pj_stun_sock_cfg_default().
218  */
219 typedef struct pj_stun_sock_cfg
220 {
221     /**
222      * The group lock to be used by the STUN socket. If NULL, the STUN socket
223      * will create one internally.
224      *
225      * Default: NULL
226      */
227     pj_grp_lock_t *grp_lock;
228 
229     /**
230      * Packet buffer size.
231      *
232      * Default value is PJ_STUN_SOCK_PKT_LEN.
233      */
234     unsigned max_pkt_size;
235 
236     /**
237      * Specify the number of simultaneous asynchronous read operations to
238      * be invoked to the ioqueue. Having more than one read operations will
239      * increase performance on multiprocessor systems since the application
240      * will be able to process more than one incoming packets simultaneously.
241      * Default value is 1.
242      */
243     unsigned async_cnt;
244 
245     /**
246      * Specify the interface where the socket should be bound to. If the
247      * address is zero, socket will be bound to INADDR_ANY. If the address
248      * is non-zero, socket will be bound to this address only, and the
249      * transport will have only one address alias (the \a alias_cnt field
250      * in #pj_stun_sock_info structure. If the port is set to zero, the
251      * socket will bind at any port (chosen by the OS).
252      */
253     pj_sockaddr bound_addr;
254 
255     /**
256      * Specify the port range for STUN socket binding, relative to the start
257      * port number specified in \a bound_addr. Note that this setting is only
258      * applicable when the start port number is non zero.
259      *
260      * Default value is zero.
261      */
262     pj_uint16_t	port_range;
263 
264     /**
265      * Specify the STUN keep-alive duration, in seconds. The STUN transport
266      * does keep-alive by sending STUN Binding request to the STUN server.
267      * If this value is zero, the PJ_STUN_KEEP_ALIVE_SEC value will be used.
268      * If the value is negative, it will disable STUN keep-alive.
269      */
270     int ka_interval;
271 
272     /**
273      * QoS traffic type to be set on this transport. When application wants
274      * to apply QoS tagging to the transport, it's preferable to set this
275      * field rather than \a qos_param fields since this is more portable.
276      *
277      * Default value is PJ_QOS_TYPE_BEST_EFFORT.
278      */
279     pj_qos_type qos_type;
280 
281     /**
282      * Set the low level QoS parameters to the transport. This is a lower
283      * level operation than setting the \a qos_type field and may not be
284      * supported on all platforms.
285      *
286      * By default all settings in this structure are disabled.
287      */
288     pj_qos_params qos_params;
289 
290     /**
291      * Specify if STUN socket should ignore any errors when setting the QoS
292      * traffic type/parameters.
293      *
294      * Default: PJ_TRUE
295      */
296     pj_bool_t qos_ignore_error;
297 
298     /**
299      * Specify target value for socket receive buffer size. It will be
300      * applied using setsockopt(). When it fails to set the specified size,
301      * it will try with lower value until the highest possible is
302      * successfully set.
303      *
304      * Default: 0 (OS default)
305      */
306     unsigned so_rcvbuf_size;
307 
308     /**
309      * Specify target value for socket send buffer size. It will be
310      * applied using setsockopt(). When it fails to set the specified size,
311      * it will try with lower value until the highest possible is
312      * successfully set.
313      *
314      * Default: 0 (OS default)
315      */
316     unsigned so_sndbuf_size;
317 
318 } pj_stun_sock_cfg;
319 
320 
321 
322 /**
323  * Retrieve the name representing the specified operation.
324  */
325 PJ_DECL(const char*) pj_stun_sock_op_name(pj_stun_sock_op op);
326 
327 
328 /**
329  * Initialize the STUN transport setting with its default values.
330  *
331  * @param cfg	The STUN transport config.
332  */
333 PJ_DECL(void) pj_stun_sock_cfg_default(pj_stun_sock_cfg *cfg);
334 
335 
336 /**
337  * Create the STUN transport using the specified configuration. Once
338  * the STUN transport has been create, application should call
339  * #pj_stun_sock_start() to start the transport.
340  *
341  * @param stun_cfg	The STUN configuration which contains among other
342  *			things the ioqueue and timer heap instance for
343  *			the operation of this transport.
344  * @param af		Address family of socket. Currently pj_AF_INET()
345  *			and pj_AF_INET6() are supported.
346  * @param name		Optional name to be given to this transport to
347  *			assist debugging.
348  * @param cb		Callback to receive events/data from the transport.
349  * @param cfg		Optional transport settings.
350  * @param user_data	Arbitrary application data to be associated with
351  *			this transport.
352  * @param p_sock	Pointer to receive the created transport instance.
353  *
354  * @return		PJ_SUCCESS if the operation has been successful,
355  *			or the appropriate error code on failure.
356  */
357 PJ_DECL(pj_status_t) pj_stun_sock_create(pj_stun_config *stun_cfg,
358 					 const char *name,
359 					 int af,
360 					 const pj_stun_sock_cb *cb,
361 					 const pj_stun_sock_cfg *cfg,
362 					 void *user_data,
363 					 pj_stun_sock **p_sock);
364 
365 
366 /**
367  * Start the STUN transport. This will start the DNS SRV resolution for
368  * the STUN server (if desired), and once the server is resolved, STUN
369  * Binding request will be sent to resolve the publicly mapped address.
370  * Once the initial STUN Binding response is received, the keep-alive
371  * timer will be started.
372  *
373  * @param stun_sock	The STUN transport instance.
374  * @param domain	The domain, hostname, or IP address of the STUN
375  *			server. When this parameter contains domain name,
376  *			the \a resolver parameter must be set to activate
377  *			DNS SRV resolution.
378  * @param default_port	The default STUN port number to use when DNS SRV
379  *			resolution is not used. If DNS SRV resolution is
380  *			used, the server port number will be set from the
381  *			DNS SRV records. The recommended value for this
382  *			parameter is PJ_STUN_PORT.
383  * @param resolver	If this parameter is not NULL, then the \a domain
384  *			parameter will be first resolved with DNS SRV and
385  *			then fallback to using DNS A/AAAA resolution when
386  *			DNS SRV resolution fails. If this parameter is
387  *			NULL, the \a domain parameter will be resolved as
388  *			hostname.
389  *
390  * @return		PJ_SUCCESS if the operation has been successfully
391  *			queued, or the appropriate error code on failure.
392  *			When this function returns PJ_SUCCESS, the final
393  *			result of the allocation process will be notified
394  *			to application in \a on_status() callback.
395  */
396 PJ_DECL(pj_status_t) pj_stun_sock_start(pj_stun_sock *stun_sock,
397 				        const pj_str_t *domain,
398 				        pj_uint16_t default_port,
399 				        pj_dns_resolver *resolver);
400 
401 /**
402  * Destroy the STUN transport.
403  *
404  * @param sock		The STUN transport socket.
405  *
406  * @return		PJ_SUCCESS if the operation has been successful,
407  *			or the appropriate error code on failure.
408  */
409 PJ_DECL(pj_status_t) pj_stun_sock_destroy(pj_stun_sock *sock);
410 
411 
412 /**
413  * Associate a user data with this STUN transport. The user data may then
414  * be retrieved later with #pj_stun_sock_get_user_data().
415  *
416  * @param stun_sock	The STUN transport instance.
417  * @param user_data	Arbitrary data.
418  *
419  * @return		PJ_SUCCESS if the operation has been successful,
420  *			or the appropriate error code on failure.
421  */
422 PJ_DECL(pj_status_t) pj_stun_sock_set_user_data(pj_stun_sock *stun_sock,
423 					        void *user_data);
424 
425 /**
426  * Retrieve the previously assigned user data associated with this STUN
427  * transport.
428  *
429  * @param stun_sock	The STUN transport instance.
430  *
431  * @return		The user/application data.
432  */
433 PJ_DECL(void*) pj_stun_sock_get_user_data(pj_stun_sock *stun_sock);
434 
435 
436 /**
437  * Get the group lock for this STUN transport.
438  *
439  * @param stun_sock	The STUN transport instance.
440  *
441  * @return	        The group lock.
442  */
443 PJ_DECL(pj_grp_lock_t *) pj_stun_sock_get_grp_lock(pj_stun_sock *stun_sock);
444 
445 
446 /**
447  * Get the STUN transport info. The transport info contains, among other
448  * things, the allocated relay address.
449  *
450  * @param stun_sock	The STUN transport instance.
451  * @param info		Pointer to be filled with STUN transport info.
452  *
453  * @return		PJ_SUCCESS if the operation has been successful,
454  *			or the appropriate error code on failure.
455  */
456 PJ_DECL(pj_status_t) pj_stun_sock_get_info(pj_stun_sock *stun_sock,
457 					   pj_stun_sock_info *info);
458 
459 
460 /**
461  * Send a data to the specified address. This function may complete
462  * asynchronously and in this case \a on_data_sent() will be called.
463  *
464  * @param stun_sock	The STUN transport instance.
465  * @param send_key	Optional send key for sending the packet down to
466  *			the ioqueue. This value will be given back to
467  *			\a on_data_sent() callback
468  * @param pkt		The data/packet to be sent to peer.
469  * @param pkt_len	Length of the data.
470  * @param flag		pj_ioqueue_sendto() flag.
471  * @param dst_addr	The remote address.
472  * @param addr_len	Length of the address.
473  *
474  * @return		PJ_SUCCESS if data has been sent immediately, or
475  *			PJ_EPENDING if data cannot be sent immediately. In
476  *			this case the \a on_data_sent() callback will be
477  *			called when data is actually sent. Any other return
478  *			value indicates error condition.
479  */
480 PJ_DECL(pj_status_t) pj_stun_sock_sendto(pj_stun_sock *stun_sock,
481 					 pj_ioqueue_op_key_t *send_key,
482 					 const void *pkt,
483 					 unsigned pkt_len,
484 					 unsigned flag,
485 					 const pj_sockaddr_t *dst_addr,
486 					 unsigned addr_len);
487 
488 /**
489  * @}
490  */
491 
492 
493 PJ_END_DECL
494 
495 
496 #endif	/* __PJNATH_STUN_SOCK_H__ */
497 
498