Exemplo n.º 1
0
/**
 * This function cancels a previously created local invite
 * transaction. The cancel parameter should NOT have any via (CANCEL is
 * hop by hop). returns 0 if error return >0 if OK (returns the LABEL of
 * the cancel).*/
unsigned int t_uac_cancel( str *headers, str *body,
		unsigned int cancelled_hashIdx, unsigned int cancelled_label,
		transaction_cb cb, void* cbp)
{
	struct cell *t_invite,*cancel_cell;
	struct retr_buf *cancel,*invite;
	unsigned int len,ret;
	char *buf;

	ret=0;
	if(t_lookup_ident(&t_invite,cancelled_hashIdx,cancelled_label)<0){
		LM_ERR("failed to t_lookup_ident hash_idx=%d,"
				"label=%d\n", cancelled_hashIdx,cancelled_label);
		return 0;
	}
	/* <sanity_checks> */
	if(! is_local(t_invite))
	{
		LM_ERR("tried to cancel a non-local transaction\n");
		goto error3;
	}
	if(t_invite->uac[0].last_received < 100)
	{
		LM_WARN("trying to cancel a transaction not in "
					"Proceeding state !\n");
		goto error3;
	}
	if(t_invite->uac[0].last_received > 200)
	{
		LM_WARN("trying to cancel a completed transaction !\n");
		goto error3;
	}
	/* </sanity_checks*/
	/* <build_cell> */
	if(!(cancel_cell = build_cell(0))){
		ret=0;
		LM_ERR("no more shm memory!\n");
		goto error3;
	}
	reset_avps();
	if(cb && insert_tmcb(&(cancel_cell->tmcb_hl),
			TMCB_RESPONSE_IN|TMCB_LOCAL_COMPLETED,cb,cbp,0)!=1){
		ret=0;
		LM_ERR("short of tmcb shmem !\n");
		goto error2;
	}
	/* </build_cell> */

	/* <insert_into_hashtable> */
	cancel_cell->flags |= T_IS_LOCAL_FLAG;
	cancel_cell->hash_index=t_invite->hash_index;

	LOCK_HASH(cancel_cell->hash_index);
	insert_into_hash_table_unsafe(cancel_cell,cancel_cell->hash_index);
	ret=cancel_cell->label;
	cancel_cell->label=t_invite->label;
	UNLOCK_HASH(cancel_cell->hash_index);
	/* </insert_into_hashtable> */

	/* <prepare_cancel> */

	cancel=&cancel_cell->uac[0].request;
	invite=&t_invite->uac[0].request;

	cancel->dst.to              = invite->dst.to;
	cancel->dst.send_sock       = invite->dst.send_sock;
	cancel->dst.proto           = invite->dst.proto;
	//cancel->dst.proto_reserved1 = invite->dst.proto_reserved1;

	if(!(buf = build_uac_cancel(headers,body,t_invite,0,&len,
					&(cancel->dst)))){
		ret=0;
		LM_ERR("attempt to build a CANCEL failed\n");
		goto error1;
	}
	cancel->buffer=buf;
	cancel->buffer_len=len;
	cancel_cell->method.s = buf;
	cancel_cell->method.len = 6 /*c-a-n-c-e-l*/;
	/* </prepare_cancel> */

	/* <strart_sending> */
	cancel_cell->nr_of_outgoings++;
	if (SEND_BUFFER(cancel)==-1) {
		ret=0;
		LM_ERR("send failed\n");
		goto error1;
	}
	start_retr(cancel);
	/* </start_sending> */

	return ret;

error1:
	LOCK_HASH(cancel_cell->hash_index);
	remove_from_hash_table_unsafe(cancel_cell);
	UNLOCK_HASH(cancel_cell->hash_index);
error2:
	free_cell(cancel_cell);
error3:
	return ret;
}
Exemplo n.º 2
0
/* Continues the SIP request processing previously saved by
 * t_suspend(). The script does not continue from the same
 * point, but a separate route block is executed instead.
 *
 * Return value:
 * 	0  - success
 * 	<0 - failure
 */
int t_continue(unsigned int hash_index, unsigned int label,
		struct action *route)
{
	struct cell	*t;
	struct sip_msg	faked_req;
	struct cancel_info cancel_data;
	int	branch;
	struct ua_client *uac =NULL;
	int	ret;
	int cb_type;
	int msg_status;
	int last_uac_status;
	int reply_status;
	int do_put_on_wait;
	struct hdr_field *hdr, *prev = 0, *tmp = 0;

	if (t_lookup_ident(&t, hash_index, label) < 0) {
		LM_ERR("transaction not found\n");
		return -1;
	}

	if (!(t->flags & T_ASYNC_SUSPENDED)) {
		LM_WARN("transaction is not suspended [%u:%u]\n", hash_index, label);
		return -2;
	}

	if (t->flags & T_CANCELED) {
		t->flags &= ~T_ASYNC_SUSPENDED;
		/* The transaction has already been canceled,
		 * needless to continue */
		UNREF(t); /* t_unref would kill the transaction */
		/* reset T as we have no working T anymore */
		set_t(T_UNDEFINED, T_BR_UNDEFINED);
		return 1;
	}

	/* The transaction has to be locked to protect it
	 * form calling t_continue() multiple times simultaneously */
	LOCK_ASYNC_CONTINUE(t);

	t->flags |= T_ASYNC_CONTINUE;   /* we can now know anywhere in kamailio
					 * that we are executing post a suspend */

	/* which route block type were we in when we were suspended */
	cb_type =  FAILURE_CB_TYPE;;
	switch (t->async_backup.backup_route) {
		case REQUEST_ROUTE:
			cb_type = FAILURE_CB_TYPE;
			break;
		case FAILURE_ROUTE:
			cb_type = FAILURE_CB_TYPE;
			break;
		case TM_ONREPLY_ROUTE:
			cb_type = ONREPLY_CB_TYPE;
			break;
		case BRANCH_ROUTE:
			cb_type = FAILURE_CB_TYPE;
			break;
	}

	if(t->async_backup.backup_route != TM_ONREPLY_ROUTE){
		branch = t->async_backup.blind_uac;	/* get the branch of the blind UAC setup 
			* during suspend */
		if (branch >= 0) {
			stop_rb_timers(&t->uac[branch].request);
 
			if (t->uac[branch].last_received != 0) {
				/* Either t_continue() has already been
				* called or the branch has already timed out.
				* Needless to continue. */
				t->flags &= ~T_ASYNC_SUSPENDED;
				UNLOCK_ASYNC_CONTINUE(t);
				UNREF(t); /* t_unref would kill the transaction */
				return 1;
			}

			/* Set last_received to something >= 200,
			 * the actual value does not matter, the branch
			 * will never be picked up for response forwarding.
			 * If last_received is lower than 200,
			 * then the branch may tried to be cancelled later,
			 * for example when t_reply() is called from
			 * a failure route => deadlock, because both
			 * of them need the reply lock to be held. */
			t->uac[branch].last_received=500;
			uac = &t->uac[branch];
		}
		/* else
			Not a huge problem, fr timer will fire, but CANCEL
			will not be sent. last_received will be set to 408. */

		/* We should not reset kr here to 0 as it's quite possible before continuing the dev. has correctly set the
		 * kr by, for example, sending a transactional reply in code - resetting here will cause a dirty log message
		 * "WARNING: script writer didn't release transaction" to appear in log files. TODO: maybe we need to add 
		 * a special kr for async?
		 * reset_kr();
		 */

		/* fake the request and the environment, like in failure_route */
		if (!fake_req(&faked_req, t->uas.request, 0 /* extra flags */, uac)) {
			LM_ERR("building fake_req failed\n");
			ret = -1;
			goto kill_trans;
		}
		faked_env( t, &faked_req, 1);

		/* execute the pre/post -script callbacks based on original route block */
		if (exec_pre_script_cb(&faked_req, cb_type)>0) {
			if (run_top_route(route, &faked_req, 0)<0)
				LM_ERR("failure inside run_top_route\n");
			exec_post_script_cb(&faked_req, cb_type);
		}

		/* TODO: save_msg_lumps should clone the lumps to shm mem */

		/* restore original environment and free the fake msg */
		faked_env( t, 0, 1);
		free_faked_req(&faked_req, t);

		/* update the flags */
		t->uas.request->flags = faked_req.flags;

		if (t->uas.status < 200) {
			/* No final reply has been sent yet.
			* Check whether or not there is any pending branch.
			*/
			for (	branch = 0;
				branch < t->nr_of_outgoings;
				branch++
			) {
				if (t->uac[branch].last_received < 200)
					break;
			}

			if (branch == t->nr_of_outgoings) {
			/* There is not any open branch so there is
			* no chance that a final response will be received. */
				ret = 0;
				goto kill_trans;
			}
		}

	} else {
		branch = t->async_backup.backup_branch;

		init_cancel_info(&cancel_data);

		LM_DBG("continuing from a suspended reply"
				" - resetting the suspend branch flag\n");

		if (t->uac[branch].reply) {
		t->uac[branch].reply->msg_flags &= ~FL_RPL_SUSPENDED;
                } else {
			LM_WARN("no reply in t_continue for branch. not much we can do\n");
			return 0;
		}
                
		if (t->uas.request) t->uas.request->msg_flags&= ~FL_RPL_SUSPENDED;

		faked_env( t, t->uac[branch].reply, 1);

		if (exec_pre_script_cb(t->uac[branch].reply, cb_type)>0) {
			if (run_top_route(route, t->uac[branch].reply, 0)<0){
				LOG(L_ERR, "ERROR: t_continue_reply: Error in run_top_route\n");
			}
			exec_post_script_cb(t->uac[branch].reply, cb_type);
		}

		LM_DBG("restoring previous environment");
		faked_env( t, 0, 1);

		/*lock transaction replies - will be unlocked when reply is relayed*/
		LOCK_REPLIES( t );
		if ( is_local(t) ) {
			LM_DBG("t is local - sending reply with status code: [%d]\n",
					t->uac[branch].reply->first_line.u.reply.statuscode);
			reply_status = local_reply( t, t->uac[branch].reply, branch,
					t->uac[branch].reply->first_line.u.reply.statuscode,
					&cancel_data );
			if (reply_status == RPS_COMPLETED) {
				/* no more UAC FR/RETR (if I received a 2xx, there may
				* be still pending branches ...
				*/
				cleanup_uac_timers( t );
				if (is_invite(t)) cancel_uacs(t, &cancel_data, F_CANCEL_B_KILL);
				/* There is no need to call set_final_timer because we know
				* that the transaction is local */
				put_on_wait(t);
			}else if (unlikely(cancel_data.cancel_bitmap)){
				/* cancel everything, even non-INVITEs (e.g in case of 6xx), use
				* cancel_b_method for canceling unreplied branches */
				cancel_uacs(t, &cancel_data, cfg_get(tm,tm_cfg, cancel_b_flags));
			}

		} else {
			LM_DBG("t is not local - relaying reply with status code: [%d]\n",
					t->uac[branch].reply->first_line.u.reply.statuscode);
			do_put_on_wait = 0;
			if(t->uac[branch].reply->first_line.u.reply.statuscode>=200){
				do_put_on_wait = 1;
			}
			reply_status=relay_reply( t, t->uac[branch].reply, branch,
					t->uac[branch].reply->first_line.u.reply.statuscode,
					&cancel_data, do_put_on_wait );
			if (reply_status == RPS_COMPLETED) {
				/* no more UAC FR/RETR (if I received a 2xx, there may
				be still pending branches ...
				*/
				cleanup_uac_timers( t );
				/* 2xx is a special case: we can have a COMPLETED request
				* with branches still open => we have to cancel them */
				if (is_invite(t) && cancel_data.cancel_bitmap) 
					cancel_uacs( t, &cancel_data,  F_CANCEL_B_KILL);
				/* FR for negative INVITES, WAIT anything else */
				/* Call to set_final_timer is embedded in relay_reply to avoid
				* race conditions when reply is sent out and an ACK to stop
				* retransmissions comes before retransmission timer is set.*/
			}else if (unlikely(cancel_data.cancel_bitmap)){
				/* cancel everything, even non-INVITEs (e.g in case of 6xx), use
				* cancel_b_method for canceling unreplied branches */
				cancel_uacs(t, &cancel_data, cfg_get(tm,tm_cfg, cancel_b_flags));
			}

		}
		t->uac[branch].request.flags|=F_RB_REPLIED;

		if (reply_status==RPS_ERROR){
			goto done;
		}

		/* update FR/RETR timers on provisional replies */

		msg_status=t->uac[branch].reply->REPLY_STATUS;
		last_uac_status=t->uac[branch].last_received;

		if (is_invite(t) && msg_status<200 &&
			( cfg_get(tm, tm_cfg, restart_fr_on_each_reply) ||
			( (last_uac_status<msg_status) &&
			((msg_status>=180) || (last_uac_status==0)) )
		) ) { /* provisional now */
			restart_rb_fr(& t->uac[branch].request, t->fr_inv_timeout);
			t->uac[branch].request.flags|=F_RB_FR_INV; /* mark fr_inv */
		}
            
	}

done:
	UNLOCK_ASYNC_CONTINUE(t);

	if(t->async_backup.backup_route != TM_ONREPLY_ROUTE){
		/* unref the transaction */
		t_unref(t->uas.request);
	} else {
		tm_ctx_set_branch_index(T_BR_UNDEFINED);        
		/* unref the transaction */
		t_unref(t->uac[branch].reply);
		LOG(L_DBG,"DEBUG: t_continue_reply: Freeing earlier cloned reply\n");

		/* free lumps that were added during reply processing */
		del_nonshm_lump( &(t->uac[branch].reply->add_rm) );
		del_nonshm_lump( &(t->uac[branch].reply->body_lumps) );
		del_nonshm_lump_rpl( &(t->uac[branch].reply->reply_lump) );

		/* free header's parsed structures that were added */
		for( hdr=t->uac[branch].reply->headers ; hdr ; hdr=hdr->next ) {
			if ( hdr->parsed && hdr_allocs_parse(hdr) &&
				(hdr->parsed<(void*)t->uac[branch].reply ||
				hdr->parsed>=(void*)t->uac[branch].end_reply)) {
				clean_hdr_field(hdr);
				hdr->parsed = 0;
			}
		}

		/* now go through hdr_fields themselves and remove the pkg allocated space */
		hdr = t->uac[branch].reply->headers;
		while (hdr) {
			if ( hdr && ((void*)hdr<(void*)t->uac[branch].reply ||
				(void*)hdr>=(void*)t->uac[branch].end_reply)) {
				//this header needs to be freed and removed form the list.
				if (!prev) {
					t->uac[branch].reply->headers = hdr->next;
				} else {
					prev->next = hdr->next;
				}
				tmp = hdr;
				hdr = hdr->next;
				pkg_free(tmp);
			} else {
				prev = hdr;
				hdr = hdr->next;
			}
		}
		sip_msg_free(t->uac[branch].reply);
		t->uac[branch].reply = 0;
	}

	/*This transaction is no longer suspended so unsetting the SUSPEND flag*/
	t->flags &= ~T_ASYNC_SUSPENDED;


	return 0;

kill_trans:
	t->flags &= ~T_ASYNC_SUSPENDED;
	/* The script has hopefully set the error code. If not,
	 * let us reply with a default error. */
	if ((kill_transaction_unsafe(t,
		tm_error ? tm_error : E_UNSPEC)) <=0
	) {
		LOG(L_ERR, "ERROR: t_continue: "
			"reply generation failed\n");
		/* The transaction must be explicitely released,
		 * no more timer is running */
		UNLOCK_ASYNC_CONTINUE(t);
		t_release_transaction(t);
	} else {
		UNLOCK_ASYNC_CONTINUE(t);
	}

	if(t->async_backup.backup_route != TM_ONREPLY_ROUTE){
		t_unref(t->uas.request);
	} else {
		/* unref the transaction */
		t_unref(t->uac[branch].reply);
	}
	return ret;
}