t_reply.c File Reference

TM :: Reply handling. More...

#include "../../hash_func.h"
#include "../../dprint.h"
#include "../../config.h"
#include "../../parser/parser_f.h"
#include "../../ut.h"
#include "../../timer.h"
#include "../../error.h"
#include "../../action.h"
#include "../../dset.h"
#include "../../tags.h"
#include "../../data_lump.h"
#include "../../data_lump_rpl.h"
#include "../../usr_avp.h"
#include "h_table.h"
#include "t_hooks.h"
#include "t_funcs.h"
#include "t_reply.h"
#include "t_cancel.h"
#include "t_msgbuilder.h"
#include "t_lookup.h"
#include "t_fwd.h"
#include "fix_lumps.h"
#include "t_stats.h"
#include "uac.h"

Include dependency graph for t_reply.c:

Go to the source code of this file.

Functions

static int _reply (struct cell *trans, struct sip_msg *p_msg, unsigned int code, str *text, int lock)

Send a UAS reply.

static int _reply_light (struct cell *trans, char *buf, unsigned int len, unsigned int code, char *to_tag, unsigned int to_tag_len, int lock, struct bookmark *bm)

void cleanup_uac_timers (struct cell *t)

Cleanup UAC timers on a transaction.

static int do_dns_failover (struct cell *t)

Do DNS failover.

static int fake_req (struct sip_msg *faked_req, struct sip_msg *shm_msg, struct ua_server *uas, struct ua_client *uac)

Fake a request.

static void faked_env (struct cell *t, struct sip_msg *msg)

Setup or restore a faked environment conforming with the message.

static void free_faked_req (struct sip_msg *faked_req, struct cell *t)

Free faked requests.

unsigned int get_on_negative (void)

unsigned int get_on_reply (void)

static int is_3263_failure (struct cell *t)

Test for DNS failover according RFC 3363 and 3261.

enum rps local_reply (struct cell *t, struct sip_msg *p_msg, int branch, unsigned int msg_status, branch_bm_t *cancel_bitmap)

"UAC" above transaction layer

enum rps relay_reply (struct cell *t, struct sip_msg *p_msg, int branch, unsigned int msg_status, branch_bm_t *cancel_bitmap)

Decide what and when shall be relayed upstream.

int reply_received (struct sip_msg *p_msg)

Called whenever a reply for our module is received.

static int run_failure_handlers (struct cell *t)

Run failure handlers.

static int send_ack (struct sip_msg *rpl, struct cell *trans, int branch)

Build and send an ACK to a negative reply.

void set_final_timer (struct cell *t)

Set final timer on a transaction.

static int store_reply (struct cell *trans, int branch, struct sip_msg *rpl)

int t_get_picked_branch (void)

returns the picked branch

int t_get_reply_totag (struct sip_msg *msg, str *totag)

void t_on_negative (unsigned int go_to)

Set which 'reply' structure to take if only negative replies arrive.

void t_on_reply (unsigned int go_to)

static int t_pick_branch (struct cell *t, int *res_code)

Select a branch for forwarding.

int t_reply (struct cell *t, struct sip_msg *p_msg, unsigned int code, str *text)

Small wrapper around _reply with locking.

int t_reply_unsafe (struct cell *t, struct sip_msg *p_msg, unsigned int code, str *text)

Small wrapper around _reply without locking.

int t_reply_with_body (struct cell *trans, unsigned int code, str *text, str *body, str *new_header, str *to_tag)

int t_retransmit_reply (struct cell *t)

Retransmits the last sent inbound reply.

static enum rps t_should_relay_response (struct cell *Trans, int new_code, int branch, int *should_store, int *should_relay, branch_bm_t *cancel_bitmap, struct sip_msg *reply)

Decide about reply processing and resulting transaction state.

void tm_init_tags (void)

int unmatched_totag (struct cell *t, struct sip_msg *ack)

Checks if the message was previously acknowledged.

static void update_local_tags (struct cell *trans, struct bookmark *bm, char *dst_buffer, char *src_buffer)

Update local tags in transaction.

static int update_totag_set (struct cell *t, struct sip_msg *ok)

Append a newly received tag from a 200/INVITE to transaction's set.

Variables

int _tm_branch_index

int disable_6xx_block = 0

int drop_stateless_replies = 0

static int goto_on_negative = 0

static int goto_on_reply = 0

int onreply_avp_mode = 0

static int picked_branch = -1

int restart_fr_on_each_reply = 1

static str tm_tag = {tm_tags,TOTAG_VALUE_LEN}

char * tm_tag_suffix

char tm_tags [TOTAG_VALUE_LEN]

Detailed Description

TM :: Reply handling.

Module: TM :: Stateful transaction handling

Definition in file t_reply.c.

Function Documentation

static int _reply	(	struct cell *	trans,
		struct sip_msg *	p_msg,
		unsigned int	code,
		str *	text,
		int	lock
	)			`[static]`

Send a UAS reply.

Returns:: 1 if everything was OK or -1 for errors

Definition at line 454 of file t_reply.c.

References _reply_light(), add_lump_rpl(), buf, build_res_buf_from_sip_req(), calc_crc_suffix(), get_to, len, LUMP_RPL_HDR, print_dset(), REQ_RPLD, _str::s, set_kr(), tm_tag_suffix, sip_msg::to, and TOTAG_VALUE_LEN.

Referenced by t_reply(), and t_reply_unsafe().

static int _reply_light	(	struct cell *	trans,
		char *	buf,
		unsigned int	len,
		unsigned int	code,
		char *	to_tag,
		unsigned int	to_tag_len,
		int	lock,
		struct bookmark *	bm
	)			`[static]`

void cleanup_uac_timers ( struct cell * t )

Cleanup UAC timers on a transaction.

Definition at line 1073 of file t_reply.c.

References cell::first_branch, retr_buf::fr_timer, LM_DBG, ua_client::request, reset_timer(), retr_buf::retr_timer, and cell::uac.

Referenced by _reply_light(), local_reply(), reply_received(), and t_release_transaction().

static int do_dns_failover ( struct cell * t ) [inline, static]

Do DNS failover.

Returns:: 0 on success, -1 on failures

Definition at line 726 of file t_reply.c.

References append_branch(), ua_client::br_flags, retr_buf::dst, fake_req(), faked_env(), sip_msg::force_send_socket, free_faked_req(), get_next_su(), LM_DBG, LM_ERR, picked_branch, ua_client::proxy, ua_client::request, ua_server::request, t_forward_nonack(), dest_info::to, cell::uac, cell::uas, and ua_client::uri.

Referenced by t_should_relay_response().

static int fake_req	(	struct sip_msg *	faked_req,
		struct sip_msg *	shm_msg,
		struct ua_server *	uas,
		struct ua_client *	uac
	)			`[inline, static]`

Fake a request.

Returns:: 1 on success, 0 on errors

Definition at line 538 of file t_reply.c.

References ua_client::br_flags, sip_msg::dst_uri, sip_msg::flags, sip_msg::id, _str::len, LM_ERR, sip_msg::new_uri, sip_msg::parsed_uri_ok, pkg_free, pkg_malloc, ua_server::request, _str::s, setb0flags(), and ua_client::uri.

Referenced by do_dns_failover(), and run_failure_handlers().

static void faked_env	(	struct cell *	t,
		struct sip_msg *	msg
	)			`[inline, static]`

Setup or restore a faked environment conforming with the message.

If msg is set -> it will fake the envinronmental vars conforming with the message, if NULL the environment will be restored to the original

Parameters:

	t	transaction
	msg	SIP message or NULL

Definition at line 499 of file t_reply.c.

References bind_address, retr_buf::dst, FAILURE_ROUTE, get_t(), ua_client::request, dest_info::send_sock, set_avp_list(), set_route_type, set_t(), swap_route_type, cell::uac, and cell::user_avps.

Referenced by do_dns_failover(), and run_failure_handlers().

static void free_faked_req	(	struct sip_msg *	faked_req,
		struct cell *	t
	)			`[inline, static]`

Free faked requests.

Parameters:

	faked_req	SIP message with faked request
	t	transaction

Definition at line 604 of file t_reply.c.

References sip_msg::add_rm, sip_msg::body_lumps, clean_msg_clone(), del_nonshm_lump_rpl(), del_notflaged_lumps(), sip_msg::dst_uri, ua_server::end_request, LUMPFLAG_SHMEM, sip_msg::new_uri, pkg_free, sip_msg::reply_lump, ua_server::request, _str::s, and cell::uas.

Referenced by do_dns_failover(), and run_failure_handlers().

unsigned int get_on_negative ( void )

Definition at line 180 of file t_reply.c.

References goto_on_negative.

Referenced by init_new_t().

unsigned int get_on_reply ( void )

Definition at line 184 of file t_reply.c.

References goto_on_reply.

Referenced by init_new_t().

static int is_3263_failure ( struct cell * t ) [inline, static]

Test for DNS failover according RFC 3363 and 3261.

Test for DNS failover, according to RFC 3263 and RFC 3261, this means a 503 reply with Retr-After header or timeout with no reply.

Parameters:

t

transaction

Returns:: 1 if this is a RFC 3263 failure, 0 otherwise

Definition at line 696 of file t_reply.c.

References FAKED_REPLY, ua_client::flags, HDR_RETRY_AFTER_T, sip_msg::headers, ua_client::last_received, LM_DBG, hdr_field::next, NULL, picked_branch, ua_client::reply, T_UAC_HAS_RECV_REPLY, hdr_field::type, and cell::uac.

Referenced by t_should_relay_response().

enum rps local_reply	(	struct cell *	t,
		struct sip_msg *	p_msg,
		int	branch,
		unsigned int	msg_status,
		branch_bm_t *	cancel_bitmap
	)

"UAC" above transaction layer

This is the "UAC" above transaction layer; if a final reply is received, it triggers a callback.

Note:: It assumes it is entered locked with REPLY_LOCK and it returns unlocked!

Returns:: reply_status

Definition at line 1306 of file t_reply.c.

References cancel_uacs(), cleanup_uac_timers(), FAKED_REPLY, get_cseq, has_tran_tmcbs, is_invite, ua_client::last_received, LM_DBG, METHOD_INVITE, put_on_wait(), ua_client::reply, RPS_ERROR, run_trans_callbacks(), stats_trans_rpl, ua_server::status, store_reply(), t_should_relay_response(), TMCB_E2EACK_IN, TMCB_LOCAL_COMPLETED, TMCB_LOCAL_RESPONSE_OUT, TMCB_RESPONSE_OUT, TMCB_RESPONSE_PRE_OUT, cell::uac, cell::uas, UNLOCK_REPLIES, update_totag_set(), and which_cancel().

Referenced by fake_reply(), and reply_received().

enum rps relay_reply	(	struct cell *	t,
		struct sip_msg *	p_msg,
		int	branch,
		unsigned int	msg_status,
		branch_bm_t *	cancel_bitmap
	)

Decide what and when shall be relayed upstream.

This is the code which decides what and when shall be relayed upstream.

Note:: It assumes it is entered locked with REPLY_LOCK and it returns unlocked!

Returns:: reply reason

Definition at line 1120 of file t_reply.c.

References retr_buf::activ_type, sip_msg::add_rm, buf, retr_buf::buffer, build_res_buf_from_sip_req(), build_res_buf_from_sip_res(), calc_crc_suffix(), cancel_uacs(), retr_buf::dst, error_text(), FAKED_REPLY, free_via_clen_lump(), get_to, has_tran_tmcbs, is_invite, ua_client::last_received, _str::len, LM_DBG, LM_ERR, NULL, pkg_free, cell::relayed_reply_branch, ua_client::reply, REPLY_OVERBUFFER_LEN, ua_server::request, ua_server::response, RPS_COMPLETED, RPS_ERROR, run_trans_callbacks(), _str::s, SEND_PR_BUFFER, set_extra_tmcb_params(), set_final_timer(), shm_resize, sip_msg_free, stats_trans_rpl, ua_server::status, store_reply(), t_reply_unsafe(), t_should_relay_response(), tm_tag_suffix, TMCB_E2EACK_IN, TMCB_RESPONSE_FWDED, TMCB_RESPONSE_OUT, TMCB_RESPONSE_PRE_OUT, sip_msg::to, cell::uac, cell::uas, UNLOCK_REPLIES, update_local_tags(), and update_totag_set().

Referenced by cancel_invite(), fake_reply(), and reply_received().

int reply_received ( struct sip_msg * p_msg )

Called whenever a reply for our module is received.

This function is called whenever a reply for our module is received, we need to register this function on module initialization.

Parameters:

p_msg

SIP message

Returns:: 0 - core router stops, 1 - core router relay statelessly

Definition at line 1384 of file t_reply.c.

References _tm_branch_index, ACT_FL_DROP, ua_client::br_flags, sip_msg::branch_index, retr_buf::buffer, cancel_branch(), cancel_uacs(), cleanup_uac_timers(), drop_stateless_replies, ua_client::flags, sip_msg::flags, cell::flags, fr_inv_avp2timer(), FR_INV_TIMER_LIST, retr_buf::fr_timer, get_cseq, get_t(), getb0flags(), HDR_RETRY_AFTER_F, if_update_stat, is_invite, is_local, ua_client::last_received, LM_DBG, LM_ERR, ua_client::local_cancel, local_reply(), LOCK_REPLIES, METHOD_CANCEL, no_autoack, NULL, cell::on_reply, onreply_avp_mode, onreply_rlist, parse_headers(), put_on_wait(), relay_reply(), ua_server::request, ua_client::request, reset_timer(), restart_fr_on_each_reply, retr_buf::retr_list, retr_buf::retr_timer, RPS_COMPLETED, RPS_PROVISIONAL, RT_T2, run_top_route(), _str::s, send_ack(), set_avp_list(), set_t(), set_timer(), setb0flags(), ua_server::status, t_check(), T_NO_DNS_FAILOVER_FLAG, T_UAC_HAS_RECV_REPLY, T_UAC_TO_CANCEL_FLAG, T_UNDEFINED, t_unref(), tm_enable_stats, tm_rcv_rpls, cell::uac, cell::uas, UNLOCK_REPLIES, and cell::user_avps.

static int run_failure_handlers ( struct cell * t ) [inline, static]

Run failure handlers.

Returns:: 1 if a failure_route processes, 0 otherwise

Definition at line 628 of file t_reply.c.

References check_hdrs_changes(), failure_rlist, fake_req(), faked_env(), sip_msg::flags, free_faked_req(), has_tran_tmcbs, ua_client::last_received, LM_ERR, LM_WARN, METHOD_CANCEL, sip_msg::msg_flags, cell::on_negative, picked_branch, tmcb_head_list::reg_types, ua_client::reply, REQ_LINE, ua_server::request, run_top_route(), run_trans_callbacks(), cell::tmcb_hl, TMCB_ON_FAILURE, cell::uac, and cell::uas.

Referenced by t_should_relay_response().

static int send_ack	(	struct sip_msg *	rpl,
		struct cell *	trans,
		int	branch
	)			`[static]`

Build and send an ACK to a negative reply.

Returns:: 0 on success, -1 for errors

Definition at line 302 of file t_reply.c.

References ACK, ACK_LEN, build_dlg_ack(), build_local(), HDR_EOH_F, HDR_TO_F, is_local, hdr_field::len, _str::len, LM_ERR, hdr_field::name, parse_headers(), ua_client::request, _str::s, SEND_PR_BUFFER, shm_free, sip_msg::to, and cell::uac.

Referenced by reply_received().

void set_final_timer ( struct cell * t )

Set final timer on a transaction.

Definition at line 1049 of file t_reply.c.

References force_retr(), is_local, METHOD_INVITE, put_on_wait(), cell::relayed_reply_branch, ua_server::request, ua_server::response, start_retr(), ua_server::status, and cell::uas.

Referenced by _reply_light(), and relay_reply().

static int store_reply	(	struct cell *	trans,
		int	branch,
		struct sip_msg *	rpl
	)			`[static]`

Definition at line 1086 of file t_reply.c.

References FAKED_REPLY, LM_ERR, ua_client::reply, sip_msg_cloner(), and cell::uac.

Referenced by local_reply(), and relay_reply().

int t_get_picked_branch ( void )

returns the picked branch

Definition at line 134 of file t_reply.c.

References picked_branch.

Referenced by load_tm(), pv_get_tm_reply_code(), pv_t_update_rpl(), t_check_status(), and t_local_replied().

int t_get_reply_totag	(	struct sip_msg *	msg,
		str *	totag
	)

Definition at line 124 of file t_reply.c.

References calc_crc_suffix(), NULL, and tm_tag_suffix.

Referenced by load_tm().

void t_on_negative ( unsigned int go_to )

Set which 'reply' structure to take if only negative replies arrive.

Definition at line 152 of file t_reply.c.

References get_t(), goto_on_negative, cell::on_negative, and T_UNDEFINED.

Referenced by script_init(), and w_t_on_negative().

void t_on_reply ( unsigned int go_to )

Definition at line 166 of file t_reply.c.

References get_t(), goto_on_reply, cell::on_reply, and T_UNDEFINED.

Referenced by script_init(), and w_t_on_reply().

static int t_pick_branch	(	struct cell *	t,
		int *	res_code
	)			`[inline, static]`

Select a branch for forwarding.

Returns:: 0..X ... branch number, -1 for errors, -2 can't decide yet -- incomplete branches present

Definition at line 770 of file t_reply.c.

References retr_buf::buffer, cell::first_branch, ua_client::last_received, LM_DBG, ua_client::request, _str::s, cell::uac, and was_cancelled.

Referenced by t_should_relay_response().

int t_reply	(	struct cell *	t,
		struct sip_msg *	p_msg,
		unsigned int	code,
		str *	text
	)

Small wrapper around _reply with locking.

Definition at line 1029 of file t_reply.c.

References _reply().

Referenced by cancel_invite(), kill_transaction(), t_relay_to(), and w_t_reply().

int t_reply_unsafe	(	struct cell *	t,
		struct sip_msg *	p_msg,
		unsigned int	code,
		str *	text
	)

Small wrapper around _reply without locking.

Definition at line 1039 of file t_reply.c.

References _reply().

Referenced by relay_reply(), and w_t_reply().

int t_reply_with_body	(	struct cell *	trans,
		unsigned int	code,
		str *	text,
		str *	body,
		str *	new_header,
		str *	to_tag
	)

Definition at line 1586 of file t_reply.c.

References _reply_light(), add_lump_rpl(), build_res_buf_from_sip_req(), free_lump_rpl(), _str::len, LM_DBG, LM_ERR, LUMP_RPL_BODY, LUMP_RPL_HDR, REQ_RPLD, ua_server::request, _str::s, set_kr(), cell::uas, unlink_lump_rpl(), and UNREF.

Referenced by load_tm(), and mi_tm_reply().

int t_retransmit_reply ( struct cell * t )

Retransmits the last sent inbound reply.

Parameters:

t

request for which I want to retransmit an associated reply

Returns:: 1 on succes, -1 on errors

Definition at line 986 of file t_reply.c.

References BUF_SIZE, retr_buf::buffer, retr_buf::dst, _str::len, len, LM_CRIT, LM_DBG, LOCK_REPLIES, ua_server::response, _str::s, SEND_PR_BUFFER, dest_info::send_sock, cell::uas, and UNLOCK_REPLIES.

Referenced by retransmission_handler(), t_check_trans(), and t_newtran().

static enum rps t_should_relay_response	(	struct cell *	Trans,
		int	new_code,
		int	branch,
		int *	should_store,
		int *	should_relay,
		branch_bm_t *	cancel_bitmap,
		struct sip_msg *	reply
	)			`[static]`

Decide about reply processing and resulting transaction state.

Decide about reply processing and resulting transaction state. This is the neurological point of reply processing -- called from within a REPLY_LOCK, t_should_relay_response decides how a reply shall be processed and how transaction state is affected. Checks if the new reply (with new_code status) should be sent or not based on the current transaction status.

Returns:: the branch number (0,1,...) which should be relayed, -1 if nothing to be relayed

Definition at line 812 of file t_reply.c.

References disable_6xx_block, do_dns_failover(), cell::flags, has_tran_tmcbs, is_3263_failure(), is_hopbyhop_cancel, is_invite, ua_client::last_received, LM_CRIT, LM_DBG, cell::nr_of_outgoings, NULL, cell::on_negative, picked_branch, ua_client::proxy, ua_client::reply, RPS_COMPLETED, RPS_DISCARDED, RPS_PROVISIONAL, RPS_PUSHED_AFTER_COMPLETION, RPS_STORE, run_failure_handlers(), ua_server::status, T_NO_DNS_FAILOVER_FLAG, T_NO_NEW_BRANCHES_FLAG, t_pick_branch(), TMCB_ON_FAILURE, cell::uac, cell::uas, and which_cancel().

Referenced by local_reply(), and relay_reply().

void tm_init_tags ( void )

Definition at line 189 of file t_reply.c.

References init_tags(), TM_TAG_SEPARATOR, tm_tag_suffix, and tm_tags.

Referenced by mod_init().

int unmatched_totag	(	struct cell *	t,
		struct sip_msg *	ack
	)

Checks if the message was previously acknowledged.

Returns:: 0 if the message was previously acknowledged (i.e., no E2EACK callback is needed) and 1 if the callback shall be executed

Definition at line 200 of file t_reply.c.

References totag_elem::acked, cell::fwded_totags, get_to, HDR_TO_F, _str::len, LM_DBG, LM_ERR, totag_elem::next, parse_headers(), _str::s, totag_elem::tag, and sip_msg::to.

Referenced by t_newtran().

static void update_local_tags	(	struct cell *	trans,
		struct bookmark *	bm,
		char *	dst_buffer,
		char *	src_buffer
	)			`[inline, static]`

Update local tags in transaction.

Definition at line 230 of file t_reply.c.

References _str::len, ua_server::local_totag, _str::s, bookmark::to_tag_val, and cell::uas.

Referenced by _reply_light(), and relay_reply().

static int update_totag_set	(	struct cell *	t,
		struct sip_msg *	ok
	)			`[inline, static]`

Append a newly received tag from a 200/INVITE to transaction's set.

Append a newly received tag from a 200/INVITE to transaction's set, (only safe if called from within a REPLY_LOCK).

Returns:: 1 if such a to tag already exists, 0 on errors and if a new TO tag was created

Definition at line 249 of file t_reply.c.

References cell::fwded_totags, get_to, _str::len, LM_CRIT, LM_DBG, LM_ERR, totag_elem::next, hdr_field::parsed, _str::s, s, shm_free, shm_lock, shm_malloc_unsafe, shm_unlock, totag_elem::tag, and sip_msg::to.

Referenced by local_reply(), and relay_reply().

Variable Documentation

int _tm_branch_index

Definition at line 73 of file t_fwd.c.

int disable_6xx_block = 0

disable the 6xx fork-blocking - default no (as per RFC3261)

Definition at line 108 of file t_reply.c.

Referenced by t_should_relay_response().

int drop_stateless_replies = 0

drop responses matching no client transaction (draft-sparks-sip-invfix-03)

Definition at line 105 of file t_reply.c.

Referenced by reply_received().

int goto_on_negative = 0 [static]

where to go if there is no positive reply

Definition at line 118 of file t_reply.c.

Referenced by get_on_negative(), and t_on_negative().

int goto_on_reply = 0 [static]

where to go on receipt of reply

Definition at line 120 of file t_reply.c.

Referenced by get_on_reply(), and t_on_reply().

int onreply_avp_mode = 0

Definition at line 103 of file t_reply.c.

Referenced by reply_received().

int picked_branch = -1 [static]

Definition at line 115 of file t_reply.c.

Referenced by do_dns_failover(), is_3263_failure(), run_failure_handlers(), t_get_picked_branch(), and t_should_relay_response().

int restart_fr_on_each_reply = 1

restart fr timer on each provisional reply, default yes

Definition at line 102 of file t_reply.c.

Referenced by reply_received().

str tm_tag = {tm_tags,TOTAG_VALUE_LEN} [static]

Definition at line 112 of file t_reply.c.

char* tm_tag_suffix

Definition at line 113 of file t_reply.c.

Referenced by _reply(), new_dlg_uas(), relay_reply(), t_get_reply_totag(), and tm_init_tags().

char tm_tags[TOTAG_VALUE_LEN]

private place where we create to-tags for replies

Definition at line 111 of file t_reply.c.

Referenced by new_dlg_uas(), and tm_init_tags().


Functions
static int	_reply (struct cell trans, struct sip_msg p_msg, unsigned int code, str *text, int lock)
	Send a UAS reply.
static int	_reply_light (struct cell trans, char buf, unsigned int len, unsigned int code, char to_tag, unsigned int to_tag_len, int lock, struct bookmark bm)
void	cleanup_uac_timers (struct cell *t)
	Cleanup UAC timers on a transaction.
static int	do_dns_failover (struct cell *t)
	Do DNS failover.
static int	fake_req (struct sip_msg faked_req, struct sip_msg shm_msg, struct ua_server uas, struct ua_client uac)
	Fake a request.
static void	faked_env (struct cell t, struct sip_msg msg)
	Setup or restore a faked environment conforming with the message.
static void	free_faked_req (struct sip_msg faked_req, struct cell t)
	Free faked requests.
unsigned int	get_on_negative (void)
unsigned int	get_on_reply (void)
static int	is_3263_failure (struct cell *t)
	Test for DNS failover according RFC 3363 and 3261.
enum rps	local_reply (struct cell t, struct sip_msg p_msg, int branch, unsigned int msg_status, branch_bm_t *cancel_bitmap)
	"UAC" above transaction layer
enum rps	relay_reply (struct cell t, struct sip_msg p_msg, int branch, unsigned int msg_status, branch_bm_t *cancel_bitmap)
	Decide what and when shall be relayed upstream.
int	reply_received (struct sip_msg *p_msg)
	Called whenever a reply for our module is received.
static int	run_failure_handlers (struct cell *t)
	Run failure handlers.
static int	send_ack (struct sip_msg rpl, struct cell trans, int branch)
	Build and send an ACK to a negative reply.
void	set_final_timer (struct cell *t)
	Set final timer on a transaction.
static int	store_reply (struct cell trans, int branch, struct sip_msg rpl)
int	t_get_picked_branch (void)
	returns the picked branch
int	t_get_reply_totag (struct sip_msg msg, str totag)
void	t_on_negative (unsigned int go_to)
	Set which 'reply' structure to take if only negative replies arrive.
void	t_on_reply (unsigned int go_to)
static int	t_pick_branch (struct cell t, int res_code)
	Select a branch for forwarding.
int	t_reply (struct cell t, struct sip_msg p_msg, unsigned int code, str *text)
	Small wrapper around _reply with locking.
int	t_reply_unsafe (struct cell t, struct sip_msg p_msg, unsigned int code, str *text)
	Small wrapper around _reply without locking.
int	t_reply_with_body (struct cell trans, unsigned int code, str text, str body, str new_header, str *to_tag)
int	t_retransmit_reply (struct cell *t)
	Retransmits the last sent inbound reply.
static enum rps	t_should_relay_response (struct cell Trans, int new_code, int branch, int should_store, int should_relay, branch_bm_t cancel_bitmap, struct sip_msg *reply)
	Decide about reply processing and resulting transaction state.
void	tm_init_tags (void)
int	unmatched_totag (struct cell t, struct sip_msg ack)
	Checks if the message was previously acknowledged.
static void	update_local_tags (struct cell trans, struct bookmark bm, char dst_buffer, char src_buffer)
	Update local tags in transaction.
static int	update_totag_set (struct cell t, struct sip_msg ok)
	Append a newly received tag from a 200/INVITE to transaction's set.
Variables
int	_tm_branch_index
int	disable_6xx_block = 0
int	drop_stateless_replies = 0
static int	goto_on_negative = 0
static int	goto_on_reply = 0
int	onreply_avp_mode = 0
static int	picked_branch = -1
int	restart_fr_on_each_reply = 1
static str	tm_tag = {tm_tags,TOTAG_VALUE_LEN}
char *	tm_tag_suffix
char	tm_tags [TOTAG_VALUE_LEN]