tm: new config parameter - remap_503_500

- option to disable remapping of 503 response code to 500

modules/tm/README

@@ -58,6 +58,7 @@ Juha Heinanen
         1.4.38. faked_reply_prio (integer)
         1.4.39. local_cancel_reason (boolean)
         1.4.40. e2e_cancel_reason (boolean)
+        1.4.41. remap_503_500 (boolean)
 
    1.5. Functions
 
@@ -1188,6 +1189,21 @@ modparam("tm", "local_cancel_reason", 0)
 modparam("tm", "e2e_cancel_reason", 0)
 ...
 
+1.4.41. remap_503_500 (boolean)
+
+   Enables/disables conversion of 503 response code to 500. By default it
+   is enabled, based on the SIP RFC requirement. This is global setting
+   for all received replies handled by TM. To do it per transaction basis,
+   let this option disabled, set a failure route and then do
+   t_reply("500", "...") inside it.
+
+   Default value is 1 (enabled).
+
+   Example 41. Set remap_503_500 parameter
+...
+modparam("tm", "remap_503_500", 0)
+...
+
 1.5. Functions
 
 1.5.1. t_relay([host, port])
@@ -1209,7 +1225,7 @@ modparam("tm", "e2e_cancel_reason", 0)
    Returns a negative value on failure -- you may still want to send a
    negative reply upstream statelessly not to leave upstream UAC in lurch.
 
-   Example 41. t_relay usage
+   Example 42. t_relay usage
 ...
 if (!t_relay())
 {
@@ -1236,7 +1252,7 @@ if (!t_relay())
    derived from the message uri (using sip sepcific DNS lookups), but with
    the protocol corresponding to the function name.
 
-   Example 42. t_relay_to_udp usage
+   Example 43. t_relay_to_udp usage
 ...
 if (src_ip==10.0.0.0/8)
         t_relay_to_udp("1.2.3.4", "5060"); # sent to 1.2.3.4:5060 over udp
@@ -1276,7 +1292,7 @@ else
    Meaning of the parameters is as follows:
      * failure_route - Failure route block to be called.
 
-   Example 43. t_on_failure usage
+   Example 44. t_on_failure usage
 ...
 route {
     t_on_failure("1");
@@ -1302,7 +1318,7 @@ failure_route[1] {
    Meaning of the parameters is as follows:
      * onreply_route - Onreply route block to be called.
 
-   Example 44. t_on_reply usage
+   Example 45. t_on_reply usage
 ...
 loadmodule "/usr/local/lib/ser/modules/nathelper.so"
 ...
@@ -1334,7 +1350,7 @@ es');
    Meaning of the parameters is as follows:
      * branch_route - branch route block to be called.
 
-   Example 45. t_on_branch usage
+   Example 46. t_on_branch usage
 ...
 route {
         t_on_branch("1");
@@ -1353,7 +1369,7 @@ branch_route[1] {
    the only way a script can add a new transaction in an atomic way.
    Typically, it is used to deploy a UAS.
 
-   Example 46. t_newtran usage
+   Example 47. t_newtran usage
 ...
 if (t_newtran()) {
     log("UAS logic");
@@ -1372,7 +1388,7 @@ if (t_newtran()) {
      * code - Reply code number.
      * reason_phrase - Reason string.
 
-   Example 47. t_reply usage
+   Example 48. t_reply usage
 ...
 t_reply("404", "Not found");
 ...
@@ -1385,7 +1401,7 @@ t_reply("404", "Not found");
    none was found. However this is safely (atomically) done using
    t_newtran.
 
-   Example 48. t_lookup_request usage
+   Example 49. t_lookup_request usage
 ...
 if (t_lookup_request()) {
     ...
@@ -1396,7 +1412,7 @@ if (t_lookup_request()) {
 
    Retransmits a reply sent previously by UAS transaction.
 
-   Example 49. t_retransmit_reply usage
+   Example 50. t_retransmit_reply usage
 ...
 t_retransmit_reply();
 ...
@@ -1406,7 +1422,7 @@ t_retransmit_reply();
    Remove transaction from memory (it will be first put on a wait timer to
    absorb delayed messages).
 
-   Example 50. t_release usage
+   Example 51. t_release usage
 ...
 t_release();
 ...
@@ -1420,7 +1436,7 @@ t_release();
      * ip - IP address where the message should be sent.
      * port - Port number.
 
-   Example 51. t_forward_nonack usage
+   Example 52. t_forward_nonack usage
 ...
 t_forward_nonack("1.2.3.4", "5060");
 ...
@@ -1459,7 +1475,7 @@ t_forward_nonack("1.2.3.4", "5060");
 
    See also: fr_timer, fr_inv_timer, t_reset_fr().
 
-   Example 52. t_set_fr usage
+   Example 53. t_set_fr usage
 ...
 route {
         t_set_fr(10000); # set only fr invite timeout to 10s
@@ -1486,7 +1502,7 @@ branch_route[1] {
 
    See also: fr_timer, fr_inv_timer, t_set_fr.
 
-   Example 53. t_reset_fr usage
+   Example 54. t_reset_fr usage
 ...
 route {
 ...
@@ -1512,7 +1528,7 @@ route {
 
    See also: max_inv_lifetime, max_noninv_lifetime, t_reset_max_lifetime.
 
-   Example 54. t_set_max_lifetime usage
+   Example 55. t_set_max_lifetime usage
 ...
 route {
     if (src_ip=1.2.3.4)
@@ -1534,7 +1550,7 @@ route {
 
    See also: max_inv_lifetime, max_noninv_lifetime, t_set_max_lifetime.
 
-   Example 55. t_reset_max_lifetime usage
+   Example 56. t_reset_max_lifetime usage
 ...
 route {
 ...
@@ -1572,7 +1588,7 @@ route {
 
    See also: retr_timer1, retr_timer2, t_reset_retr().
 
-   Example 56. t_set_retr usage
+   Example 57. t_set_retr usage
 ...
 route {
         t_set_retr(250, 0); # set only T1 to 250 ms
@@ -1599,7 +1615,7 @@ branch_route[1] {
 
    See also: retr_timer1, retr_timer2, t_set_retr.
 
-   Example 57. t_reset_retr usage
+   Example 58. t_reset_retr usage
 ...
 route {
 ...
@@ -1615,7 +1631,7 @@ route {
 
    See also: auto_inv_100.
 
-   Example 58. t_set_auto_inv_100 usage
+   Example 59. t_set_auto_inv_100 usage
 ...
 route {
 ...
@@ -1629,7 +1645,7 @@ route {
    Returns true if the failure route is executed for a branch that did
    timeout. It can be used only from the failure_route.
 
-   Example 59. t_branch_timeout usage
+   Example 60. t_branch_timeout usage
 ...
 failure_route[0]{
         if (t_branch_timeout()){
@@ -1644,7 +1660,7 @@ failure_route[0]{
    receive at least one reply in the past (the "current" reply is not
    taken into account). It can be used only from the failure_route.
 
-   Example 60. t_branch_replied usage
+   Example 61. t_branch_replied usage
 ...
 failure_route[0]{
         if (t_branch_timeout()){
@@ -1661,7 +1677,7 @@ failure_route[0]{
    Returns true if at least one of the current transactions branches did
    timeout.
 
-   Example 61. t_any_timeout usage
+   Example 62. t_any_timeout usage
 ...
 failure_route[0]{
         if (!t_branch_timeout()){
@@ -1678,7 +1694,7 @@ failure_route[0]{
    receive some reply in the past. If called from a failure or onreply
    route, the "current" reply is not taken into account.
 
-   Example 62. t_any_replied usage
+   Example 63. t_any_replied usage
 ...
 onreply_route[0]{
         if (!t_any_replied()){
@@ -1692,7 +1708,7 @@ onreply_route[0]{
    Returns true if "code" is the final reply received (or locally
    generated) in at least one of the current transactions branches.
 
-   Example 63. t_grep_status usage
+   Example 64. t_grep_status usage
 ...
 onreply_route[0]{
         if (t_grep_status("486")){
@@ -1705,7 +1721,7 @@ onreply_route[0]{
 
    Returns true if the current transaction was canceled.
 
-   Example 64. t_is_canceled usage
+   Example 65. t_is_canceled usage
 ...
 failure_route[0]{
         if (t_is_canceled()){
@@ -1719,7 +1735,7 @@ failure_route[0]{
    Returns true if the current transaction has already been expired, i.e.
    the max_inv_lifetime/max_noninv_lifetime interval has already elapsed.
 
-   Example 65. t_is_expired usage
+   Example 66. t_is_expired usage
 ...
 failure_route[0]{
         if (t_is_expired()){
@@ -1740,7 +1756,7 @@ failure_route[0]{
    CANCELs were successfully sent to the pending branches, true if the
    INVITE was not found, and false in case of any error.
 
-   Example 66. t_relay_cancel usage
+   Example 67. t_relay_cancel usage
 if (method == CANCEL) {
         if (!t_relay_cancel()) {  # implicit drop if relaying was successful,
                                   # nothing to do
@@ -1767,7 +1783,7 @@ if (method == CANCEL) {
    overwritten with the flags of the INVITE. isflagset() can be used to
    check the flags of the previously forwarded INVITE in this case.
 
-   Example 67. t_lookup_cancel usage
+   Example 68. t_lookup_cancel usage
 if (method == CANCEL) {
         if (t_lookup_cancel()) {
                 log("INVITE transaction exists");
@@ -1797,7 +1813,7 @@ if (method == CANCEL) {
    Dropping replies works only if a new branch is added to the
    transaction, or it is explicitly replied in the script!
 
-   Example 68. t_drop_replies() usage
+   Example 69. t_drop_replies() usage
 ...
 failure_route[0]{
         if (t_check_status("5[0-9][0-9]")){
@@ -1828,7 +1844,7 @@ failure_route[0]{
    The transaction must be created by t_newtran() before calling
    t_save_lumps().
 
-   Example 69. t_save_lumps() usage
+   Example 70. t_save_lumps() usage
 route {
         ...
         t_newtran();
@@ -1898,7 +1914,7 @@ failure_route[1] {
 
    This function can be used from REQUEST_ROUTE.
 
-   Example 70. t_load_contacts usage
+   Example 71. t_load_contacts usage
 ...
 if (!t_load_contacts()) {
         sl_send_reply("500", "Server Internal Error - Cannot load contacts");
@@ -1939,7 +1955,7 @@ if (!t_load_contacts()) {
    anymore set. Based on that test, you can then use t_set_fr() function
    to set timers according to your needs.
 
-   Example 71. t_next_contacts usage
+   Example 72. t_next_contacts usage
 ...
 # First call after t_load_contacts() when transaction does not exist yet
 # and contacts should be available
@@ -2003,7 +2019,7 @@ Note
 
    See also: t_lookup_request(), t_lookup_cancel().
 
-   Example 72. t_check_trans usage
+   Example 73. t_check_trans usage
 if ( method == "CANCEL" && !t_check_trans())
         sl_reply("403", "cancel out of the blue forbidden");
 # note: in this example t_check_trans() can be replaced by t_lookup_cancel()
@@ -2018,7 +2034,7 @@ if ( method == "CANCEL" && !t_check_trans())
 
    See also: disable_6xx_block.
 
-   Example 73. t_set_disable_6xx usage
+   Example 74. t_set_disable_6xx usage
 ...
 route {
 ...
@@ -2033,7 +2049,7 @@ route {
 
    See also: use_dns_failover.
 
-   Example 74. t_set_disable_failover usage
+   Example 75. t_set_disable_failover usage
 ...
 route {
 ...
@@ -2064,7 +2080,7 @@ route {
      * hostport - address in "host:port" format. It can be given via an
        AVP.
 
-   Example 75. t_replicate usage
+   Example 76. t_replicate usage
 ...
 # sent to 1.2.3.4:5060 over tcp
 t_replicate("sip:1.2.3.4:5060;transport=tcp");
@@ -2099,7 +2115,7 @@ t_replicate_to_udp("1.2.3.4", "5060");
             effect anymore).
           + 0x04 - disable dns failover.
 
-   Example 76. t_replicate usage
+   Example 77. t_replicate usage
 ...
 # sent to 1.2.3.4:5060 over tcp
 t_relay_to("tcp:1.2.3.4:5060");
@@ -2122,7 +2138,7 @@ t_relay_to("0x01");
 
    See also: e2e_cancel_reason.
 
-   Example 77. t_set_no_e2e_cancel_reason usage
+   Example 78. t_set_no_e2e_cancel_reason usage
 ...
 route {
 ...
@@ -2145,7 +2161,7 @@ opying
      * onreply_route - the function returns true if an onreply route is
        set to be executed.
 
-   Example 78. t_replicate usage
+   Example 79. t_replicate usage
 ...
 if(!t_is_set("failure_route"))
     LM_DBG("no failure route will be executed for current transaction\n");

modules/tm/doc/params.xml

@@ -1265,6 +1265,28 @@ modparam("tm", "local_cancel_reason", 0)
 			<programlisting>
 ...
 modparam("tm", "e2e_cancel_reason", 0)
+...
+			</programlisting>
+		</example>
+	</section>
+
+	<section id="remap_503_500">
+		<title><varname>remap_503_500</varname> (boolean)</title>
+		<para>
+			Enables/disables conversion of 503 response code to 500. By default
+			it is enabled, based on the SIP RFC requirement. This is global
+			setting for all received replies handled by TM. To do it per
+			transaction basis, let this option disabled, set a failure route
+			and then do t_reply("500", "...") inside it.
+		</para>
+		<para>
+			Default value is 1 (enabled).
+		</para>
+		<example>
+			<title>Set <varname>remap_503_500</varname> parameter</title>
+			<programlisting>
+...
+modparam("tm", "remap_503_500", 0)
 ...
 			</programlisting>
 		</example>

modules/tm/t_reply.c

@@ -177,6 +177,9 @@ static int goto_on_reply=0;
 /* where to go on receipt of reply without transaction context */
 int goto_on_sl_reply=0;
 
+/* remap 503 response code to 500 */
+extern int tm_remap_503_500;
+
 /* how to deal with winning branch reply selection in failure_route
  * can be overwritten per transaction with t_drop_replies(...)
  * Values:
@@ -1759,7 +1762,7 @@ enum rps relay_reply( struct cell *t, struct sip_msg *p_msg, int branch,
 			}
 		} else {
 			relayed_code=relayed_msg->REPLY_STATUS;
-			if (relayed_code==503){
+			if (relayed_code==503 && tm_remap_503_500){
 				/* replace a final 503 with a 500:
 				 * generate a "FAKE" reply and a new to_tag (for easier
 				 *  debugging)*/

modules/tm/tm.c

@@ -308,6 +308,8 @@ static char *fr_timer_param = 0 /*FR_TIMER_AVP*/;
 static char *fr_inv_timer_param = 0 /*FR_INV_TIMER_AVP*/;
 static char *contacts_avp_param = 0;
 
+int tm_remap_503_500 = 1;
+
 static rpc_export_t tm_rpc[];
 
 static int fixup_t_check_status(void** param, int param_no);
@@ -522,6 +524,7 @@ static param_export_t params[]={
 	{"local_ack_mode",      PARAM_INT, &default_tm_cfg.local_ack_mode        },
 	{"failure_reply_mode",  PARAM_INT, &failure_reply_mode                   },
 	{"faked_reply_prio",    PARAM_INT, &faked_reply_prio                     },
+	{"remap_503_500",       PARAM_INT, &tm_remap_503_500                     },
 #ifdef CANCEL_REASON_SUPPORT
 	{"local_cancel_reason", PARAM_INT, &default_tm_cfg.local_cancel_reason   },
 	{"e2e_cancel_reason",   PARAM_INT, &default_tm_cfg.e2e_cancel_reason     },