core: Added IP_FREEBIND flag durring socket initialization

cfg.lex

@@ -336,6 +336,7 @@ DST_BLST_TCP_IMASK	dst_blacklist_tcp_imask
 DST_BLST_TLS_IMASK	dst_blacklist_tls_imask
 DST_BLST_SCTP_IMASK	dst_blacklist_sctp_imask
 
+IP_FREE_BIND		ip_free_bind|ip_freebind|ipfreebind
 
 PORT	port
 STAT	statistics
@@ -751,6 +752,7 @@ IMPORTFILE      "import_file"
 								return DST_BLST_TLS_IMASK; }
 <INITIAL>{DST_BLST_SCTP_IMASK}	{ count(); yylval.strval=yytext;
 								return DST_BLST_SCTP_IMASK; }
+<INITIAL>{IP_FREE_BIND}	{ count(); yylval.strval=yytext; return IP_FREE_BIND; }
 <INITIAL>{PORT}	{ count(); yylval.strval=yytext; return PORT; }
 <INITIAL>{STAT}	{ count(); yylval.strval=yytext; return STAT; }
 <INITIAL>{MAXBUFFER}	{ count(); yylval.strval=yytext; return MAXBUFFER; }

cfg.y

@@ -366,6 +366,7 @@ extern char *default_routename;
 %token DST_BLST_TCP_IMASK
 %token DST_BLST_TLS_IMASK
 %token DST_BLST_SCTP_IMASK
+%token IP_FREE_BIND
 
 %token PORT
 %token STAT
@@ -869,6 +870,8 @@ assign_stm:
 		IF_DST_BLACKLIST(default_core_cfg.blst_sctp_imask=$3);
 	}
 	| DST_BLST_SCTP_IMASK error { yyerror("number(flags) expected"); }
+	| IP_FREE_BIND EQUAL intno { _sr_ip_free_bind=$3; }
+	| IP_FREE_BIND EQUAL error { yyerror("int value expected"); }
 	| PORT EQUAL NUMBER   { port_no=$3; }
 	| STAT EQUAL STRING {
 		#ifdef STATS

globals.h

@@ -213,6 +213,7 @@ extern int rt_timer1_policy; /* "fast" timer, SCHED_OTHER */
 extern int rt_timer2_policy; /* "slow" timer, SCHED_OTHER */
 
 extern int http_reply_parse;
+extern int _sr_ip_free_bind;
 
 #ifdef USE_DNS_CACHE
 extern int dns_cache_init; /* if 0, the DNS cache is not initialized at startup */

modules/sctp/sctp_server.c

@@ -468,7 +468,18 @@ static int sctp_init_sock_opt_common(int s, int af)
 			/* continue since this is not critical */
 		}
 	}
-
+
+#if defined(IP_FREEBIND)
+	/* allow bind to non local address.
+	 * useful when daemon started before network initialized */
+	optval = 1;
+	if (_sr_ip_free_bind && setsockopt(s, IPPROTO_IP, IP_FREEBIND,
+				(void*)&optval, sizeof(optval)) ==-1) {
+		LM_WARN("setsockopt freebind failed: %s\n", strerror(errno));
+		/* continue since this is not critical */
+	}
+#endif
+
 	/* set receive buffer: SO_RCVBUF*/
 	if (cfg_get(sctp, sctp_cfg, so_rcvbuf)){
 		optval=cfg_get(sctp, sctp_cfg, so_rcvbuf);
@@ -479,7 +490,7 @@ static int sctp_init_sock_opt_common(int s, int af)
 			/* continue, non-critical */
 		}
 	}
-	
+
 	/* set send buffer: SO_SNDBUF */
 	if (cfg_get(sctp, sctp_cfg, so_sndbuf)){
 		optval=cfg_get(sctp, sctp_cfg, so_sndbuf);

receive.c

@@ -59,6 +59,8 @@
 #include <mem/dmalloc.h>
 #endif
 
+int _sr_ip_free_bind = 0;
+
 unsigned int msg_no=0;
 /* address preset vars */
 str default_global_address={0,0};

tcp_main.c

@@ -2762,6 +2762,17 @@ int tcp_init(struct socket_info* sock_info)
 			/* continue since this is not critical */
 		}
 	}
+
+#if defined(IP_FREEBIND)
+	/* allow bind to non local address.
+	 * useful when daemon started before network initialized */
+	if (_sr_ip_free_bind && setsockopt(sock_info->socket, IPPROTO_IP,
+				IP_FREEBIND, (void*)&optval, sizeof(optval)) ==-1) {
+		LM_WARN("setsockopt freebind failed: %s\n", strerror(errno));
+		/* continue since this is not critical */
+	}
+#endif
+
 #ifdef HAVE_TCP_DEFER_ACCEPT
 	/* linux only */
 	if ((optval=cfg_get(tcp, tcp_cfg, defer_accept))){

udp_server.c

@@ -319,6 +319,16 @@ int udp_init(struct socket_info* sock_info)
 	}
 #endif
 
+#if defined(IP_FREEBIND)
+	/* allow bind to non local address.
+	 * useful when daemon started before network initialized */
+	optval = 1;
+	if (_sr_ip_free_bind && setsockopt(sock_info->socket, IPPROTO_IP,
+				IP_FREEBIND, (void*)&optval, sizeof(optval)) ==-1) {
+		LM_WARN("setsockopt freebind failed: %s\n", strerror(errno));
+		/* continue since this is not critical */
+	}
+#endif
 #ifdef USE_MCAST
 	if ((sock_info->flags & SI_IS_MCAST) 
 	    && (setup_mcast_rcvr(sock_info->socket, addr)<0)){