Adding TTL option

srsepc/hdr/mbms-gw/mbms-gw.h

@@ -52,6 +52,7 @@ typedef struct {
   std::string sgi_mb_if_mask;
   std::string m1u_multi_addr;
   std::string m1u_multi_if;
+  int         m1u_multi_ttl;
 } mbms_gw_args_t;
 
 struct pseudo_hdr

srsepc/mbms.conf.example

@@ -16,6 +16,7 @@ sgi_mb_if_addr = 172.16.0.254
 sgi_mb_if_mask = 255.255.255.255
 m1u_multi_addr = 239.255.0.1
 m1u_multi_if   = 127.0.1.200
+m1u_multi_ttl  = 1
 
 ####################################################################
 # Log configuration

srsepc/src/mbms-gw/main.cc

@@ -105,6 +105,7 @@ parse_args(all_args_t *args, int argc, char* argv[]) {
     ("mbms_gw.sgi_mb_if_mask",      bpo::value<string>(&mbms_gw_sgi_mb_if_mask)->default_value("255.255.255.255"), "SGi-mb TUN interface mask.")
     ("mbms_gw.m1u_multi_addr",      bpo::value<string>(&mbms_gw_m1u_multi_addr)->default_value("239.255.0.1"), "M1-u GTPu destination multicast address.")
     ("mbms_gw.m1u_multi_if",        bpo::value<string>(&mbms_gw_m1u_multi_if)->default_value("127.0.1.200"), "Local interface IP for M1-U multicast packets.")
+    ("mbms_gw.m1u_multi_ttl",       bpo::value<int>(&args->mbms_gw_args.m1u_multi_ttl)->default_value(1), "TTL for M1-U multicast packets.")
 
     ("log.all_level",     bpo::value<string>(&args->log_args.all_level)->default_value("info"),   "ALL log level")
     ("log.all_hex_limit", bpo::value<int>(&args->log_args.all_hex_limit)->default_value(32),  "ALL log hex dump limit")

srsepc/src/mbms-gw/mbms-gw.cc

@@ -238,7 +238,13 @@ mbms_gw::init_m1_u(mbms_gw_args_t *args)
   if(setsockopt(m_m1u, IPPROTO_IP, IP_MULTICAST_IF, (char*)&local_if, sizeof(struct in_addr))<0){
     perror("Error setting multicast interface.\n");
   } else {
-    printf("Multicast interface specified.\n");
+    printf("Multicast interface specified. Address: %s\n", args->m1u_multi_if.c_str());
+  }
+
+  /*Set Multicast TTL*/
+  if ( setsockopt(m_m1u, IPPROTO_IP,IP_MULTICAST_TTL,&args->m1u_multi_ttl,sizeof(args->m1u_multi_ttl)) <0 ) {
+    perror("Error setting multicast ttl.\n");
+    return srslte::ERROR_CANT_START;
   }
 
   bzero(&m_m1u_multi_addr,sizeof(m_m1u_multi_addr));