asterisk/include/asterisk/stun.h

125 lines
3.8 KiB
C

/*
* Asterisk -- An open source telephony toolkit.
*
* Copyright (C) 1999 - 2008, Digium, Inc.
*
* Mark Spencer <markster@digium.com>
*
* See http://www.asterisk.org for more information about
* the Asterisk project. Please do not directly contact
* any of the maintainers of this project for assistance;
* the project provides a web site, mailing lists and IRC
* channels for your use.
*
* This program is free software, distributed under the terms of
* the GNU General Public License Version 2. See the LICENSE file
* at the top of the source tree.
*/
/*!
* \file
*
* \brief STUN support.
*
* STUN is defined in RFC 3489.
*/
#ifndef _ASTERISK_STUN_H
#define _ASTERISK_STUN_H
#include "asterisk/network.h"
#include "asterisk/logger_category.h"
#if defined(__cplusplus) || defined(c_plusplus)
extern "C" {
#endif
/* STUN debug logging category name */
#define AST_LOG_CATEGORY_STUN "stun"
/* STUN packet debug logging category name */
#define AST_LOG_CATEGORY_STUN_PACKET "stun_packet"
uintmax_t ast_debug_category_stun_id(void);
uintmax_t ast_debug_category_stun_packet_id(void);
#define AST_DEBUG_CATEGORY_STUN ast_debug_category_stun_id() /* STUN debug logging category id */
#define AST_DEBUG_CATEGORY_STUN_PACKET ast_debug_category_stun_packet_id() /* STUN packet debug logging category id */
/*!
* \brief Log debug level STUN information
*
* \param sublevel Debug output sublevel (>= 0)
* \param ... String format and any associated arguments
*/
#define ast_debug_stun(sublevel, ...) \
ast_debug_category(sublevel, AST_DEBUG_CATEGORY_STUN, __VA_ARGS__)
/* Is logging of stun packets allowed? */
#define ast_debug_stun_packet_is_allowed \
ast_debug_category_is_allowed(AST_LOG_CATEGORY_ENABLED, AST_DEBUG_CATEGORY_STUN_PACKET)
static const int STANDARD_STUN_PORT = 3478;
enum ast_stun_result {
AST_STUN_IGNORE = 0,
AST_STUN_ACCEPT,
};
struct stun_attr;
/*!
* \brief Generic STUN request.
*
* \param s The socket used to send the request.
* \param dst If non null, the address of the STUN server.
* Only needed if the socket is not bound or connected.
* \param username If non null, add the username in the request.
* \param answer If non null, the function waits for a response and
* puts here the externally visible address.
*
* \details
* Send a generic STUN request to the server specified, possibly
* waiting for a reply and filling the answer parameter with the
* externally visible address. Note that in this case the
* request will be blocking.
*
* \note The interface may change slightly in the future.
*
* \retval 0 on success.
* \retval <0 on error.
* \retval >0 on timeout.
*/
int ast_stun_request(int s, struct sockaddr_in *dst, const char *username, struct sockaddr_in *answer);
/*! \brief callback type to be invoked on stun responses. */
typedef int (stun_cb_f)(struct stun_attr *attr, void *arg);
/*!
* \brief handle an incoming STUN message.
*
* \param s Socket to send any response to.
* \param src Address where packet came from.
* \param data STUN packet buffer to process.
* \param len Length of packet
* \param stun_cb If not NULL, callback for each STUN attribute.
* \param arg Arg to pass to callback.
*
* \details
* Do some basic sanity checks on packet size and content,
* try to extract a bit of information, and possibly reply.
* At the moment this only processes BIND requests, and returns
* the externally visible address of the request.
* If a callback is specified, invoke it with the attribute.
*
* \retval AST_STUN_ACCEPT if responed to a STUN request
* \retval AST_STUN_IGNORE
* \retval -1 on error
*/
int ast_stun_handle_packet(int s, struct sockaddr_in *src, unsigned char *data, size_t len, stun_cb_f *stun_cb, void *arg);
#if defined(__cplusplus) || defined(c_plusplus)
}
#endif
#endif /* _ASTERISK_STUN_H */