/* return 1 if a failure_route processes */
static inline int run_failure_handlers(struct cell *t)
{
static struct sip_msg faked_req;
struct sip_msg *shmem_msg;
struct ua_client *uac;
int on_failure;
shmem_msg = t->uas.request;
uac = &t->uac[picked_branch];
/* failure_route for a local UAC? */
if (!shmem_msg || REQ_LINE(shmem_msg).method_value==METHOD_CANCEL ) {
LM_WARN("no UAC or CANCEL support (%d, %d) \n",
t->on_negative, t->tmcb_hl.reg_types);
return 0;
}
/* don't start faking anything if we don't have to */
if ( !has_tran_tmcbs( t, TMCB_ON_FAILURE) && !t->on_negative ) {
LM_WARN("no negative handler (%d, %d)\n",t->on_negative,
t->tmcb_hl.reg_types);
return 1;
}
if (!fake_req(&faked_req, shmem_msg, &t->uas, uac)) {
LM_ERR("fake_req failed\n");
return 0;
}
/* fake also the env. conforming to the fake msg */
faked_env( t, &faked_req);
/* DONE with faking ;-) -> run the failure handlers */
if ( has_tran_tmcbs( t, TMCB_ON_FAILURE) ) {
run_trans_callbacks( TMCB_ON_FAILURE, t, &faked_req,
uac->reply, uac->last_received);
}
if (t->on_negative) {
/* update flags in transaction if changed by callbacks */
shmem_msg->flags = faked_req.flags;
/* avoid recursion -- if failure_route forwards, and does not
* set next failure route, failure_route will not be reentered
* on failure */
on_failure = t->on_negative;
t->on_negative=0;
/* run a reply_route action if some was marked */
run_top_route(failure_rlist[on_failure].a, &faked_req);
}
/* restore original environment and free the fake msg */
faked_env( t, 0);
free_faked_req(&faked_req,t);
/* if failure handler changed flag, update transaction context */
shmem_msg->flags = faked_req.flags;
/* branch flags do not need to be updated as this branch will be never
* used again */
return 1;
}
static inline int do_dns_failover(struct cell *t)
{
static struct sip_msg faked_req;
struct sip_msg *shmem_msg;
struct ua_client *uac;
int ret;
shmem_msg = t->uas.request;
uac = &t->uac[picked_branch];
/* check if the DNS resolver can get at least one new IP */
if ( get_next_su( uac->proxy, &uac->request.dst.to, 1)!=0 )
return -1;
LM_DBG("new destination available\n");
if (!fake_req(&faked_req, shmem_msg, &t->uas, uac)) {
LM_ERR("fake_req failed\n");
return -1;
}
/* fake also the env. conforming to the fake msg */
faked_env( t, &faked_req);
ret = -1;
/* set info as current destination */
if ( set_ruri( &faked_req, &uac->uri)!= 0)
goto done;
setb0flags( uac->br_flags );
faked_req.force_send_socket = shmem_msg->force_send_socket;
/* send it out */
if (t_forward_nonack( t, &faked_req, uac->proxy)==1)
ret = 0;
done:
/* restore original environment and free the fake msg */
faked_env( t, 0);
free_faked_req(&faked_req,t);
return ret;
}
static inline int do_dns_failover(struct cell *t)
{
static struct sip_msg faked_req;
struct sip_msg *shmem_msg;
struct sip_msg *req;
struct ua_client *uac;
dlg_t dialog;
int ret, sip_msg_len;
uac = &t->uac[picked_branch];
/* check if the DNS resolver can get at least one new IP */
if ( get_next_su( uac->proxy, &uac->request.dst.to, 1)!=0 )
return -1;
LM_DBG("new destination available\n");
if (t->uas.request==NULL) {
if (!is_local(t)) {
LM_CRIT("BUG: proxy transaction without UAS request :-/\n");
return -1;
}
/* create the cloned SIP msg -> first create a new SIP msg */
memset( &dialog, 0, sizeof(dialog));
dialog.send_sock = uac->request.dst.send_sock;
dialog.hooks.next_hop = &uac->uri;
req = buf_to_sip_msg(uac->request.buffer.s, uac->request.buffer.len,
&dialog);
if (req==NULL) {
LM_ERR("failed to generate SIP msg from previous buffer\n");
return -1;
}
/* now do the actual cloning of the SIP message */
t->uas.request = sip_msg_cloner( req, &sip_msg_len, 1);
if (t->uas.request==NULL) {
LM_ERR("cloning failed\n");
free_sip_msg(req);
return -1;
}
t->uas.end_request = ((char*)t->uas.request) + sip_msg_len;
/* free the actual SIP message, keep the clone only */
free_sip_msg(req);
/* the sip_msg structure is static in buf_to_sip_msg,
so no need to free it */
}
shmem_msg = t->uas.request;
if (!fake_req(&faked_req, shmem_msg, &t->uas, uac, 1/*with dst_uri*/)) {
LM_ERR("fake_req failed\n");
return -1;
}
/* fake also the env. conforming to the fake msg */
faked_env( t, &faked_req);
ret = -1;
/* set info as current destination */
if ( set_ruri( &faked_req, &uac->uri)!= 0)
goto done;
setb0flags( &faked_req, uac->br_flags );
faked_req.force_send_socket = shmem_msg->force_send_socket;
/* send it out */
if (t_forward_nonack( t, &faked_req, uac->proxy)==1)
ret = 0;
done:
/* restore original environment and free the fake msg */
faked_env( t, 0);
free_faked_req(&faked_req,t);
return ret;
}
/* 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;
}
int t_append_branches(void) {
struct cell *t = NULL;
struct sip_msg *orig_msg = NULL;
static struct sip_msg faked_req;
short outgoings;
int success_branch;
str current_uri;
str dst_uri, path, instance, ruid, location_ua;
struct socket_info* si;
int q, i, found;
flag_t backup_bflags = 0;
flag_t bflags = 0;
int new_branch, branch_ret, lowest_ret;
branch_bm_t added_branches;
int replies_locked = 0;
int ret = 0;
t = get_t();
if(t == NULL)
{
LM_ERR("cannot get transaction\n");
return -1;
}
LM_DBG("transaction %u:%u in status %d\n", t->hash_index, t->label, t->uas.status);
/* test if transaction has already been canceled */
if (t->flags & T_CANCELED) {
ser_error=E_CANCELED;
return -1;
}
if ((t->uas.status >= 200 && t->uas.status<=399)
|| ((t->uas.status >= 600 && t->uas.status)
&& !(t->flags & (T_6xx | T_DISABLE_6xx))) ) {
LM_DBG("transaction %u:%u in status %d: cannot append new branch\n",
t->hash_index, t->label, t->uas.status);
return -1;
}
/* set the lock on the transaction here */
LOCK_REPLIES(t);
replies_locked = 1;
outgoings = t->nr_of_outgoings;
orig_msg = t->uas.request;
LM_DBG("Call %.*s: %d (%d) outgoing branches\n",orig_msg->callid->body.len,
orig_msg->callid->body.s,outgoings, nr_branches);
lowest_ret=E_UNSPEC;
added_branches=0;
/* it's a "late" branch so the on_branch variable has already been
reset by previous execution of t_forward_nonack: we use the saved
value */
if (t->on_branch_delayed) {
/* tell add_uac that it should run branch route actions */
set_branch_route(t->on_branch_delayed);
}
if (!fake_req(&faked_req, orig_msg, 0, NULL)) {
LOG(L_ERR, "ERROR: t_append_branches: fake_req failed\n");
return -1;
}
/* fake also the env. conforming to the fake msg */
faked_env( t, &faked_req, 0);
/* DONE with faking ;-) -> run the failure handlers */
init_branch_iterator();
while((current_uri.s=next_branch( ¤t_uri.len, &q, &dst_uri, &path,
&bflags, &si, &ruid, &instance, &location_ua))) {
LM_DBG("Current uri %.*s\n",current_uri.len, current_uri.s);
found = 0;
for (i=0; i<outgoings; i++) {
if (t->uac[i].ruid.len == ruid.len
&& !memcmp(t->uac[i].ruid.s, ruid.s, ruid.len)
&& t->uac[i].uri.len == current_uri.len
&& !memcmp(t->uac[i].uri.s, current_uri.s, current_uri.len)) {
LM_DBG("branch already added [%.*s]\n", ruid.len, ruid.s);
found = 1;
break;
}
}
if (found)
continue;
setbflagsval(0, bflags);
new_branch=add_uac( t, &faked_req, ¤t_uri,
(dst_uri.len) ? (&dst_uri) : ¤t_uri,
&path, 0, si, faked_req.fwd_send_flags,
PROTO_NONE, (dst_uri.len)?0:UAC_SKIP_BR_DST_F, &instance,
&ruid, &location_ua);
LM_DBG("added branch [%.*s] with ruid [%.*s]\n", current_uri.len, current_uri.s, ruid.len, ruid.s);
/* test if cancel was received meanwhile */
if (t->flags & T_CANCELED) goto canceled;
if (new_branch>=0)
added_branches |= 1<<new_branch;
else
lowest_ret=MIN_int(lowest_ret, new_branch);
}
clear_branches();
LM_DBG("Call %.*s: %d (%d) outgoing branches after clear_branches()\n",
orig_msg->callid->body.len, orig_msg->callid->body.s,outgoings, nr_branches);
setbflagsval(0, backup_bflags);
/* update message flags, if changed in branch route */
t->uas.request->flags = faked_req.flags;
if (added_branches==0) {
if(lowest_ret!=E_CFG)
LOG(L_ERR, "ERROR: t_append_branch: failure to add branches (%d)\n", lowest_ret);
ser_error=lowest_ret;
ret = lowest_ret;
goto done;
}
ser_error=0; /* clear branch adding errors */
/* send them out now */
success_branch=0;
/* since t_append_branch can only be called from REQUEST_ROUTE, always lock replies */
for (i=outgoings; i<t->nr_of_outgoings; i++) {
if (added_branches & (1<<i)) {
branch_ret=t_send_branch(t, i, &faked_req , 0, 0 /* replies are already locked */ );
if (branch_ret>=0){ /* some kind of success */
if (branch_ret==i) { /* success */
success_branch++;
if (unlikely(has_tran_tmcbs(t, TMCB_REQUEST_OUT)))
run_trans_callbacks_with_buf( TMCB_REQUEST_OUT,
&t->uac[nr_branches].request,
&faked_req, 0, -orig_msg->REQ_METHOD);
}
else /* new branch added */
added_branches |= 1<<branch_ret;
}
}
}
if (success_branch<=0) {
/* return always E_SEND for now
* (the real reason could be: denied by onsend routes, blacklisted,
* send failed or any of the errors listed before + dns failed
* when attempting dns failover) */
ser_error=E_SEND;
/* else return the last error (?) */
ret = -1;
goto done;
}
ser_error=0; /* clear branch send errors, we have overall success */
set_kr(REQ_FWDED);
ret = success_branch;
goto done;
canceled:
DBG("t_append_branches: cannot append branches to a canceled transaction\n");
/* reset processed branches */
clear_branches();
/* restore backup flags from initial env */
setbflagsval(0, backup_bflags);
/* update message flags, if changed in branch route */
t->uas.request->flags = faked_req.flags;
/* if needed unlock transaction's replies */
/* restore the number of outgoing branches
* since new branches have not been completed */
t->nr_of_outgoings = outgoings;
ser_error=E_CANCELED;
ret = -1;
done:
/* restore original environment and free the fake msg */
faked_env( t, 0, 0);
free_faked_req(&faked_req,t);
if (likely(replies_locked)) {
replies_locked = 0;
UNLOCK_REPLIES(t);
}
return ret;
}