subscribe.c

用来作为linux中SIP SERVER,完成VOIP网络电话中服务器的功能

/*
 * Presence Agent, subscribe handling
 *
 * $Id: subscribe.c,v 1.24 2004/08/24 09:00:33 janakj Exp $
 *
 * Copyright (C) 2001-2003 FhG Fokus
 *
 * This file is part of ser, a free SIP server.
 *
 * ser is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version
 *
 * For a license to use the ser software under conditions
 * other than those described here, or to purchase support for this
 * software, please contact iptel.org by e-mail at the following addresses:
 *    [e-mail]
 *
 * ser is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License 
 * along with this program; if not, write to the Free Software 
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * History:
 * ---------
 * 2003-02-29 scratchpad compatibility abandoned
 * 2003-01-27 next baby-step to removing ZT - PRESERVE_ZT (jiri)
 */

#include <string.h>
#include "../../str.h"
#include "../../dprint.h"
#include "../../mem/mem.h"
#include "../../parser/parse_uri.h"
#include "../../parser/parse_from.h"
#include "../../parser/parse_expires.h"
#include "../../parser/parse_event.h"
#include "presentity.h"
#include "watcher.h"
#include "pstate.h"
#include "notify.h"
#include "paerrno.h"
#include "pdomain.h"
#include "pa_mod.h"
#include "ptime.h"
#include "reply.h"
#include "subscribe.h"


#define DOCUMENT_TYPE "application/cpim-pidf+xml"
#define DOCUMENT_TYPE_L (sizeof(DOCUMENT_TYPE) - 1)

static int accepts_to_event_package[N_DOCTYPES] = {
	[DOC_XPIDF] = EVENT_PRESENCE,
	[DOC_LPIDF] = EVENT_PRESENCE,
	[DOC_PIDF] = EVENT_PRESENCE,
	[DOC_WINFO] = EVENT_PRESENCE_WINFO,
	[DOC_XCAP_CHANGE] = EVENT_XCAP_CHANGE,
	[DOC_LOCATION] = EVENT_LOCATION,
};

/*
 * A static variable holding document type accepted
 * by the watcher's user agent
 */
static doctype_t acc;


/*
 * contact will be NULL if user is offline
 * fixme:locking
 */
void callback(str* _user, str *_contact, int state, void* data)
{
     presentity_t *presentity;

     get_act_time();

     presentity = (struct presentity*)data;

     if (presentity && callback_update_db) {
	  presence_tuple_t *tuple = NULL;
	  int orig;
	  LOG(L_ERR, "callback: uri=%.*s contact=%.*s state=%d\n",
	      presentity->uri.len, presentity->uri.s, (_contact ? _contact->len : 0), (_contact ? _contact->s : ""), state);
	  if (_contact) {
	       if (callback_lock_pdomain)
		    lock_pdomain(presentity->pdomain);

	       find_presence_tuple(_contact, presentity, &tuple);
	       if (!tuple) {
		    new_presence_tuple(_contact, act_time + default_expires, presentity, &tuple);
		    add_presence_tuple(presentity, tuple);
	       };

	       orig = tuple->state;

	       if (state == 0) {
		    tuple->state = PS_OFFLINE;
	       } else {
		    tuple->state = PS_ONLINE;
	       }

	       tuple->expires = act_time + default_expires;

	       db_update_presentity(presentity);

	       if (orig != state) {
		    presentity->flags |= PFLAG_PRESENCE_CHANGED;
	       }

	       if (callback_lock_pdomain)
		    unlock_pdomain(presentity->pdomain);
	  }
     }
}

/*
 * Extract plain uri -- return URI without parameters
 * The uri will be in form username@domain
 *
 */
static int extract_plain_uri(str* _uri)
{
	struct sip_uri puri;

	if (parse_uri(_uri->s, _uri->len, &puri) < 0) {
		paerrno = PA_URI_PARSE;
		LOG(L_ERR, "extract_plain_uri(): Error while parsing URI\n");
		return -1;
	}
	
	_uri->s = puri.user.s;
	_uri->len = puri.host.s + puri.host.len - _uri->s;
	return 0;
}


/*
 * Get presentity URI, which is stored in R-URI
 */
int get_pres_uri(struct sip_msg* _m, str* _puri)
{
	if (_m->new_uri.s) {
		_puri->s = _m->new_uri.s;
		_puri->len = _m->new_uri.len;
	} else {
		_puri->s = _m->first_line.u.request.uri.s;
		_puri->len = _m->first_line.u.request.uri.len;
	}
	LOG(L_ERR, "get_pres_uri: _puri=%.*s\n", _puri->len, _puri->s);
	
	if (extract_plain_uri(_puri) < 0) {
		LOG(L_ERR, "get_pres_uri(): Error while extracting plain URI\n");
		return -1;
	}

	return 0;
}


static int get_watch_uri(struct sip_msg* _m, str* _wuri, str *_dn)
{
	_wuri->s = get_from(_m)->uri.s;
	_wuri->len = get_from(_m)->uri.len;
	_dn->s = get_from(_m)->body.s;
	_dn->len = get_from(_m)->body.len;

	if (extract_plain_uri(_wuri) < 0) {
		LOG(L_ERR, "get_watch_uri(): Error while extracting plain URI\n");
		return -1;
	}
	
	return 0;
}


/*
 * Parse Accept header field body
 * FIXME: This is ugly parser, write something more clean
 */
int parse_accept(struct hdr_field* _h, doctype_t* _a)
{
	if (_h) {
		char* buffer;

		/*
		 * All implementation must support xpidf so make
		 * it the default
		 */
		*_a = DOC_XPIDF;

		buffer = pkg_malloc(_h->body.len + 1);
		if (!buffer) {
			paerrno = PA_NO_MEMORY;
			LOG(L_ERR, "parse_accept(): No memory left\n");
			return -1;
		}

		memcpy(buffer, _h->body.s, _h->body.len);
		buffer[_h->body.len] = '\0';
	
		if (strstr(buffer, "application/cpim-pidf+xml")
		    || strstr(buffer, "application/pidf+xml")) {
			*_a = DOC_PIDF;
		} else if (strstr(buffer, "application/xpidf+xml")) {
			*_a = DOC_XPIDF;
		} else if (strstr(buffer, "text/lpidf")) {
			*_a = DOC_LPIDF;
		} else if (strstr(buffer, "application/watcherinfo+xml")) {
			*_a = DOC_WINFO;
		} else if (strstr(buffer, "application/xcap-change+xml")) {
			*_a = DOC_XCAP_CHANGE;
		} else if (strstr(buffer, "application/location+xml")) {
			*_a = DOC_LOCATION;
		} else {
			*_a = DOC_XPIDF;
		}
	
		pkg_free(buffer);
		return 0;
	} else {
		/* XP messenger is not giving an accept field, so default to lpidf */
		*_a = DOC_XPIDF;
		return 0;
	}
}


/*
 * Parse all header fields that will be needed
 * to handle a SUBSCRIBE request
 */
static int parse_hfs(struct sip_msg* _m, int accept_header_required)
{
	if ( (parse_headers(_m, HDR_FROM | HDR_EVENT | HDR_EXPIRES | HDR_ACCEPT, 0)
				== -1) || (_m->from==0)||(_m->event==0)||(_m->expires==0) ||
			(_m->accept==0) ) {
		paerrno = PA_PARSE_ERR;
		LOG(L_ERR, "parse_hfs(): Error while parsing headers\n");
		return -1;
	}

	if (parse_from_header(_m) < 0) {
		paerrno = PA_FROM_ERR;
		LOG(L_ERR, "parse_hfs(): From malformed or missing\n");
		return -6;
	}

	if (_m->event) {
		if (parse_event(_m->event) < 0) {
			paerrno = PA_EVENT_PARSE;
			LOG(L_ERR, "parse_hfs(): Error while parsing Event header field\n");
			return -8;
		}
	}

	if (_m->expires) {
		if (parse_expires(_m->expires) < 0) {
			paerrno = PA_EXPIRES_PARSE;
			LOG(L_ERR, "parse_hfs(): Error while parsing Expires header field\n");
			return -9;
		}
	}

	if (_m->accept) {
		if (parse_accept(_m->accept, &acc) < 0) {
			paerrno = PA_ACCEPT_PARSE;
			LOG(L_ERR, "parse_hfs(): Error while parsing Accept header field\n");
			return -10;
		}
	} else if (accept_header_required) {
		LOG(L_ERR, "no accept header\n");
		acc = DOC_XPIDF;
	}

	return 0;
}


/*
 * Check if a message received has been constructed properly
 */
int check_message(struct sip_msg* _m)
{
	if (_m->event) {
		event_t *event;

		if (!_m->event->parsed)
			parse_event(_m->event);
		event = (event_t*)(_m->event->parsed);

		if (event && (event->parsed != accepts_to_event_package[acc])) {
			char *accept_s = NULL;
			int accept_len = 0;
			if (_m->accept && _m->accept->body.len) {
				accept_s = _m->accept->body.s;
				accept_len = _m->accept->body.len;
			}
			LOG(L_ERR, "check_message(): Accepts %.*s not valid for event package et=%.*s\n",
			    _m->accept->body.len, _m->accept->body.s, event->text.len, event->text.s);
			return -1;
		}
	}
	return 0;
}


/*
 * Create a new presentity and corresponding watcher list
 */
int create_presentity(struct sip_msg* _m, struct pdomain* _d, str* _puri, 
			     struct presentity** _p, struct watcher** _w)
{
	time_t e;
	dlg_t* dialog;
	str watch_uri;
	str watch_dn;
	event_t *event = NULL;
	int et = 0;
	if (_m->event) {
		event = (event_t*)(_m->event->parsed);
		et = event->parsed;
	} else {
		et = EVENT_PRESENCE;
	}

	if (_m->expires) {
		e = ((exp_body_t*)_m->expires->parsed)->val;
	} else {
		e = default_expires;
	}
	
	if (e == 0) {
		*_p = 0;
		*_w = 0;
		DBG("create_presentity(): expires = 0\n");
		return 0;
	}

	/* Convert to absolute time */
	e += act_time;

	if (get_watch_uri(_m, &watch_uri, &watch_dn) < 0) {
		LOG(L_ERR, "create_presentity(): Error while extracting watcher URI\n");
		return -1;
	}

	if (new_presentity(_d, _puri, _p) < 0) {
		LOG(L_ERR, "create_presentity(): Error while creating presentity\n");
		return -2;
	}

	if (tmb.new_dlg_uas(_m, 200, &dialog) < 0) {
		paerrno = PA_DIALOG_ERR;
		LOG(L_ERR, "create_presentity(): Error while creating dialog state\n");
		free_presentity(*_p);
		return -3;
	}

	if (et != EVENT_PRESENCE_WINFO) {
		if (add_watcher(*_p, &watch_uri, e, et, acc, dialog, &watch_dn, _w) < 0) {
			LOG(L_ERR, "create_presentity(): Error while adding a watcher\n");
			tmb.free_dlg(dialog);
			free_presentity(*_p);
			return -4;
		}
	} else if (et == EVENT_PRESENCE_WINFO) {
		if (add_winfo_watcher(*_p, &watch_uri, e, et, acc, dialog, &watch_dn, _w) < 0) {
			LOG(L_ERR, "create_presentity(): Error while adding a winfo watcher\n");
			tmb.free_dlg(dialog);
			free_presentity(*_p);