support for RFC 3263 improvement

- added timer M with default = B_TIMER/4.
 - when timer M triggers, next ip is tried.
 - timer M is used only when there is another address to try.

core/sip/cstring.h

@@ -64,9 +64,9 @@ struct cstring
 };
 
 #define c2stlstr(str) \
-          string(str.s,str.len)
+          string((str).s,(str).len)
 
 #define stl2cstr(str) \
-          cstring((char*)str.c_str(),str.length())
+          cstring((char*)(str).c_str(),(str).length())
 
 #endif

core/sip/resolver.h

@@ -106,6 +106,8 @@ struct dns_handle
 
     int next_ip(sockaddr_storage* sa);
 
+    //void operator = (const dns_handle& h);
+
 private:
     friend class _resolver;
     friend class dns_entry;

core/sip/sip_timers.h

@@ -27,6 +27,49 @@
 #ifndef _sip_timers_h_
 #define _sip_timers_h_
 
+/**
+ * SIP transaction timer type definition
+ */
+enum sip_timer_type {
+
+    STIMER_INVALID=0,
+
+    // INVITE client transaction
+    STIMER_A,  // Calling: (re-)send INV
+    STIMER_B,  // Calling -> Terminated
+    STIMER_D,  // Completed -> Terminated
+
+    // non-INVITE client transaction
+    STIMER_E,  // Trying/Proceeding: (re-)send request
+    STIMER_F,  // Trying/Proceeding -> Terminated
+    STIMER_K,  // Completed -> Terminated
+
+    // INVITE server transaction
+    STIMER_G,  // Completed: (re-)send response
+    STIMER_H,  // Completed -> Terminated
+    STIMER_I,  // Confirmed -> Terminated
+
+    // non-INVITE server transaction
+    STIMER_J,  // Completed -> Terminated
+
+    // These timers are not defined by
+    // RFC 3261. 
+
+    // Used to handle 200 ACKs automatically
+    // in INVITE client transactions.
+    STIMER_L,  // Terminated_200 -> Terminated
+
+    // Transport address failover timer:
+    // - used to cycle throught multiple addresses
+    //   in case the R-URI resolves to multiple addresses
+    STIMER_M
+};
+
+
+/**
+ * SIP transaction timer default values
+ */
+
 #define T1_TIMER  500 /* 500 ms */
 #define T2_TIMER 4000 /*   4 s  */
 #define T4_TIMER 5000 /*   5 s  */
@@ -60,14 +103,19 @@
 #define J_TIMER  64*T1_TIMER
 
 
-// This timer is not defined by
-// RFC 3261. But it is needed
-// to handle 200 ACKs automatically
-// in UAC transactions.
+// Following timer values are not defined by
+// RFC 3261.
 
+// Used to handle 200 ACKs automatically
+// in INVITE client transactions.
 //type 0x0b
 #define L_TIMER  64*T1_TIMER
 
+// Transport address failover timer:
+// - used to cycle throught multiple addresses
+//   in case the R-URI resolves to multiple addresses
+#define M_TIMER  (B_TIMER/4)
+
 #endif
 
 

core/sip/sip_trans.cpp

@@ -41,7 +41,8 @@ int _timer_type_lookup[] = {
     0,1,2, // STIMER_E, STIMER_F, STIMER_K
     0,1,2, // STIMER_G, STIMER_H, STIMER_I
     0,     // STIMER_J
-    2      // STIMER_L; shares the same slot as STIMER_D
+    2,     // STIMER_L; shares the same slot as STIMER_D
+    2      // STIMER_M; shares the same slot as STIMER_D/STIMER_K
 };
 
 inline timer** fetch_timer(unsigned int timer_type, timer** base)
@@ -98,7 +99,7 @@ timer* sip_trans::get_timer(unsigned int timer_type)
 }
 
 
-char _timer_name_lookup[] = {'0','A','B','D','E','F','K','G','H','I','J','L'};
+char _timer_name_lookup[] = {'0','A','B','D','E','F','K','G','H','I','J','L','M'};
 #define timer_name(type) \
     (_timer_name_lookup[(type) & 0xFFFF])
 
@@ -137,6 +138,7 @@ void trans_timer_cb(timer* t, unsigned int bucket_id, sip_trans* tr)
 	else {
 	    WARN("Transaction %p does not exist anymore\n",tr);
 	    WARN("Timer type=%c will be deleted without further processing\n",timer_name(t->type));
+	    wheeltimer::instance()->remove_timer(t);
 	}
 	bucket->unlock();
     }

core/sip/sip_trans.h

@@ -61,36 +61,6 @@ enum {
 };
 
 
-enum sip_timer_type {
-
-    STIMER_INVALID=0,
-
-    // INVITE client transaction
-    STIMER_A,  // Calling: (re-)send INV
-    STIMER_B,  // Calling: -> Terminated
-    STIMER_D,  // Completed: -> Terminated
-
-    // non-INVITE client transaction
-    STIMER_E,  // Trying/Proceeding: (re-)send request
-    STIMER_F,  // Trying/Proceeding: terminate transaction
-    STIMER_K,  // Completed: terminate transaction  
-
-    // INVITE server transaction
-    STIMER_G,  // Completed: (re-)send response
-    STIMER_H,  // Completed: -> Terminated
-    STIMER_I,  // Confirmed: -> Terminated
-
-    // non-INVITE server transaction
-    STIMER_J,  // Completed: -> Terminated
-
-    // This timer is not defined by
-    // RFC 3261. But it is needed
-    // to handle 200 ACKs automatically
-    // in INVITE client transactions.
-    STIMER_L  // Terminated_200 -> Terminated
-};
-
-
 /**
  * We support at most 3 timer per transaction,
  * which is okay according to the standard

core/sip/trans_layer.cpp

@@ -325,7 +325,7 @@ int _trans_layer::send_reply(trans_ticket* tt,
     }
 
     assert(transport);
-    // TODO: inspect topmost 'Via' and select proper addr/port (w/ received, rport)
+    // TODO: inspect topmost 'Via' and select proper addr (+resolve DNS names)
     // refs: RFC3261 18.2.2; RFC3581
     sockaddr_storage remote_ip;
     memcpy(&remote_ip,&req->remote_ip,sizeof(sockaddr_storage));
@@ -517,7 +517,7 @@ int _trans_layer::send_sl_reply(sip_msg* req, int reply_code,
     }
 
     assert(transport);
-    //TODO: select proper address depending on Via (w/ received, rport), remote_ip
+
     int err = transport->send(&req->remote_ip,reply_buf,reply_len);
     delete [] reply_buf;
 
@@ -527,15 +527,15 @@ int _trans_layer::send_sl_reply(sip_msg* req, int reply_code,
 //
 // Ref. RFC 3261 "12.2.1.1 Generating the Request"
 //
-int _trans_layer::set_next_hop(sip_msg* msg)
+int _trans_layer::set_next_hop(sip_msg* msg, 
+			       cstring* next_hop,
+			       unsigned short* next_port)
 {
     assert(msg);
 
     list<sip_header*>& route_hdrs = msg->route; 
     cstring& r_uri = msg->u.request->ruri_str;
 
-    cstring        next_hop;
-    unsigned short next_port = 0;
     int err=0;
 
     if(!route_hdrs.empty()){
@@ -572,9 +572,9 @@ int _trans_layer::set_next_hop(sip_msg* msg)
 
 	}
 
-	if (next_hop.len == 0) {
-	    next_hop  = na.uri.host;
-	    next_port = na.uri.port;
+	if (next_hop->len == 0) {
+	    *next_hop  = na.uri.host;
+	    *next_port = na.uri.port;
 	}	    
 
 	if(!is_lr){
@@ -675,22 +675,31 @@ int _trans_layer::set_next_hop(sip_msg* msg)
 	    ERROR("Invalid Request URI\n");
 	    return -1;
 	}
-	next_hop  = parsed_r_uri.host;
-	next_port = parsed_r_uri.port;
+	*next_hop  = parsed_r_uri.host;
+	*next_port = parsed_r_uri.port;
     }
 
-    DBG("next_hop:next_port is <%.*s:%u>\n", next_hop.len, next_hop.s, next_port);
+    DBG("next_hop:next_port is <%.*s:%u>\n", next_hop->len, next_hop->s, *next_port);
     
-    err = resolver::instance()->resolve_name(c2stlstr(next_hop).c_str(),
-					     &(msg->h_dns),
-					     &(msg->remote_ip),IPv4);
+    return 0;
+}
+
+
+int _trans_layer::set_destination_ip(sip_msg* msg, cstring* next_hop, unsigned short next_port)
+{
+    memset(&(msg->remote_ip),0,sizeof(sockaddr_storage));
+    int err = resolver::instance()->resolve_name(c2stlstr(*next_hop).c_str(),
+						 &(msg->h_dns),
+						 &(msg->remote_ip),IPv4);
     if(err < 0){
 	ERROR("Unresolvable Request URI\n");
 	return -1;
     }
 
-    ((sockaddr_in*)&(msg->remote_ip))->sin_port = htons(next_port);
-    
+    if(!((sockaddr_in*)&(msg->remote_ip))->sin_port) {
+	((sockaddr_in*)&(msg->remote_ip))->sin_port = htons(next_port);
+    }
+ 
     return 0;
 }
 
@@ -739,12 +748,6 @@ int _trans_layer::send_request(sip_msg* msg, trans_ticket* tt)
     tt->_bucket = 0;
     tt->_t = 0;
 
-    if(trans_layer::instance()->set_next_hop(msg) < 0){
-
-	DBG("set_next_hop failed\n");
-	return -1;
-    }
-    
     int request_len = request_line_len(msg->u.request->method_str,
 				       msg->u.request->ruri_str);
 
@@ -804,8 +807,20 @@ int _trans_layer::send_request(sip_msg* msg, trans_ticket* tt)
 	return MALFORMED_SIP_MSG;
     }
 
-    memcpy(&p_msg->remote_ip,&msg->remote_ip,sizeof(sockaddr_storage));
-    memcpy(&p_msg->h_dns,&msg->h_dns,sizeof(dns_handle));
+    cstring next_hop;
+    unsigned short next_port=0;
+
+    if(set_next_hop(p_msg,&next_hop,&next_port) < 0){
+	DBG("set_next_hop failed\n");
+	delete p_msg;
+	return -1;
+    }
+
+    if(set_destination_ip(p_msg,&next_hop,next_port) < 0){
+     	DBG("set_destination_ip failed\n");
+	delete p_msg;
+     	return -1;
+    }
 
     DBG("Sending to %s:%i <%.*s...>\n",
 	get_addr_str(((sockaddr_in*)&p_msg->remote_ip)->sin_addr).c_str(),
@@ -1164,6 +1179,7 @@ int _trans_layer::update_uac_reply(trans_bucket* bucket, sip_trans* t, sip_msg*
 
 	case TS_CALLING:
 	    t->clear_timer(STIMER_A);
+	    t->clear_timer(STIMER_M);
 	    t->clear_timer(STIMER_B);
 	    // fall through trap
 
@@ -1197,6 +1213,8 @@ int _trans_layer::update_uac_reply(trans_bucket* bucket, sip_trans* t, sip_msg*
 	    case TS_CALLING:
 
 		t->clear_timer(STIMER_A);
+		t->clear_timer(STIMER_M);
+		t->clear_timer(STIMER_B);
 
 	    case TS_PROCEEDING:
 		
@@ -1236,6 +1254,7 @@ int _trans_layer::update_uac_reply(trans_bucket* bucket, sip_trans* t, sip_msg*
 
 		t->state  = TS_TERMINATED_200;
 		t->clear_timer(STIMER_A);
+		t->clear_timer(STIMER_M);
 		t->clear_timer(STIMER_B);
 
 		t->reset_timer(STIMER_L, L_TIMER, bucket->get_id());
@@ -1285,6 +1304,7 @@ int _trans_layer::update_uac_reply(trans_bucket* bucket, sip_trans* t, sip_msg*
 	    t->state = TS_COMPLETED;
 	
 	    t->clear_timer(STIMER_E);
+	    t->clear_timer(STIMER_M);
 	    t->clear_timer(STIMER_F);
 	    t->reset_timer(STIMER_K, K_TIMER, bucket->get_id());
 	    
@@ -1322,12 +1342,23 @@ int _trans_layer::update_uac_request(trans_bucket* bucket, sip_trans*& t, sip_ms
 	    return -1;
 	}
 
+	// clear old retransmission buffer
 	delete [] t->retr_buf;
+	
+	// transfer the message buffer 
+	// to the transaction (incl. ownership)
 	t->retr_buf = msg->buf;
 	t->retr_len = msg->len;
 	msg->buf = NULL;
 	msg->len = 0;
+	
+	// copy destination address
 	memcpy(&t->retr_addr,&msg->remote_ip,sizeof(sockaddr_storage));
+
+	// remove the message;
+	delete msg;
+
+	return 0;
     }
 
     switch(msg->u.request->method){
@@ -1339,13 +1370,6 @@ int _trans_layer::update_uac_request(trans_bucket* bucket, sip_trans*& t, sip_ms
 	t->reset_timer(STIMER_B,B_TIMER,bucket->get_id());
 	break;
     
-    case sip_request::ACK:
-	// we do not need any timer here:
-	// -> TIMER L is already started.
-	
-	delete msg;
-	break;
-
     default:
 	// if transport == UDP
 	t->reset_timer(STIMER_E,E_TIMER,bucket->get_id());
@@ -1353,7 +1377,11 @@ int _trans_layer::update_uac_request(trans_bucket* bucket, sip_trans*& t, sip_ms
 	t->reset_timer(STIMER_F,F_TIMER,bucket->get_id());
 	break;
     }
-	
+
+    if(!msg->h_dns.eoip()){ // if transport == UDP
+	t->reset_timer(STIMER_M,M_TIMER,bucket->get_id());
+    }
+
     return 0;
 }
 
@@ -1653,6 +1681,33 @@ void _trans_layer::timer_expired(timer* t, trans_bucket* bucket, sip_trans* tr)
 	}
 	break;
 
+    case STIMER_M:
+	{
+	    sockaddr_storage sa;
+	    memset(&sa,0,sizeof(sockaddr_storage));
+
+	    // get the next ip
+	    if(tr->msg->h_dns.next_ip(&sa) < 0){
+		tr->clear_timer(STIMER_M);
+		return;
+	    }
+	    memcpy(&tr->msg->remote_ip,&sa,sizeof(sockaddr_storage));
+
+	    // create new branch tag
+	    compute_branch((char*)(tr->msg->via_p1->branch.s+MAGIC_BRANCH_LEN),
+			   tr->msg->callid->value,tr->msg->cseq->value);
+
+	    // reset counter for timer A & E
+	    timer* A_E_timer = tr->get_timer(STIMER_A);
+	    tr->reset_timer(A_E_timer->type,A_TIMER,bucket->get_id());
+
+	    if(!tr->msg->h_dns.eoip())
+		tr->reset_timer(STIMER_M,M_TIMER,bucket->get_id());
+	    else
+		tr->clear_timer(STIMER_M);
+	}
+	break;
+
     default:
 	ERROR("Invalid timer type %i\n",t->type);
 	break;

core/sip/trans_layer.h

@@ -153,19 +153,26 @@ public:
     int send_sl_reply(sip_msg* req, int reply_code, 
 		      const cstring& reason, 
 		      const cstring& hdrs, const cstring& body);
+    
+    /**
+     * Transaction timeout
+     */
+    void timeout(trans_bucket* bucket, sip_trans* t);
+
+protected:
 
     /**
      * Fills the address structure passed and modifies 
      * R-URI and Route headers as needed.
      */
-    int set_next_hop(sip_msg* req);
-    
+    int set_next_hop(sip_msg* msg, cstring* next_hop,
+		     unsigned short* next_port);
+
     /**
-     * Transaction timeout
+     * Fills msg->remote_ip according to next_hop and next_port.
      */
-    void timeout(trans_bucket* bucket, sip_trans* t);
+    int set_destination_ip(sip_msg* msg, cstring* next_hop, unsigned short next_port);    
 
-protected:
     /** Avoid external instantiation. @see singleton. */
     _trans_layer();
     ~_trans_layer();

core/sip/trans_table.cpp

@@ -43,7 +43,7 @@
 //
 // Global transaction table
 //
-//trans_bucket _trans_table[H_TABLE_ENTRIES];
+
 hash_table<trans_bucket> _trans_table(H_TABLE_ENTRIES);
 
 trans_bucket::trans_bucket(unsigned long id)
@@ -51,11 +51,6 @@ trans_bucket::trans_bucket(unsigned long id)
 {
 }
 
-// trans_bucket::trans_bucket()
-//     : ht_bucket<sip_trans>::ht_bucket((unsigned long)this - (unsigned long)_trans_table)
-// {
-// }
-
 trans_bucket::~trans_bucket()
 {
 }

core/sip/trans_table.h

@@ -10,16 +10,15 @@
 class trans_bucket: 
     public ht_bucket<sip_trans>
 {
+    trans_bucket(unsigned long id);
+    ~trans_bucket();
+
+    friend class hash_table<trans_bucket>;
+
 public:
+
     typedef ht_bucket<sip_trans>::value_list trans_list;
 
-    /**
-     * Kept public to allow for static construction.
-     * !!! DO CREATE ANY BUCKETS ON YOUR OWN !!!
-     */
-    // trans_bucket();
-    trans_bucket(unsigned long id);
-    ~trans_bucket();
     
     // Match a request to UAS transactions
     // in this bucket
@@ -31,12 +30,6 @@ public:
 
     sip_trans* add_trans(sip_msg* msg, int ttype);
 
-    // /**
-    //  * Remove a transaction from this bucket,
-    //  * if it was still present.
-    //  */
-    // void remove_trans(sip_trans* t);
-
 private:
     sip_trans* match_200_ack(sip_trans* t,sip_msg* msg);
     sip_trans* match_1xx_prack(sip_trans* t,sip_msg* msg);