Added config option to enable pcap.

srsepc/epc.conf.example

@@ -45,8 +45,21 @@ db_file = user_db.csv
 #####################################################################
 
 [spgw]
-gtpu_bind_addr=127.0.1.100
+gtpu_bind_addr = 127.0.1.100
-sgi_if_addr=172.16.0.1
+sgi_if_addr    = 172.16.0.1
+
+####################################################################
+# PCAP configuration
+#
+# Enable PCAP tracing of S1AP packets
+#
+# enable:   Enable or disable the PCAP.
+# filename: File name where to save the PCAP.
+#
+####################################################################
+[pcap]
+enable   = false
+filename = /tmp/epc.pcap
 
 ####################################################################
 # Log configuration

srsepc/hdr/mme/s1ap.h

@@ -128,6 +128,7 @@ private:
   mme_gtpc *m_mme_gtpc;
 
   //PCAP
+  bool              m_pcap_enable;
   srslte::s1ap_pcap m_pcap;
 };
 

srsepc/hdr/mme/s1ap_common.h

@@ -93,6 +93,8 @@ typedef struct{
   std::string   mme_name;
   std::string   dns_addr;
   std::string   mme_apn;
+  bool          pcap_enable;
+  std::string   pcap_filename;
 } s1ap_args_t;
 
 typedef struct{

srsepc/src/main.cc

@@ -106,13 +106,16 @@ parse_args(all_args_t *args, int argc, char* argv[]) {
     ("mme.tac",             bpo::value<string>(&tac)->default_value("0x0"),                  "Tracking Area Code")
     ("mme.mcc",             bpo::value<string>(&mcc)->default_value("001"),                  "Mobile Country Code")
     ("mme.mnc",             bpo::value<string>(&mnc)->default_value("01"),                   "Mobile Network Code")
-    ("mme.mme_bind_addr",   bpo::value<string>(&mme_bind_addr)->default_value("127.0.0.1"),"IP address of MME for S1 connnection")
+    ("mme.mme_bind_addr",   bpo::value<string>(&mme_bind_addr)->default_value("127.0.0.1"),  "IP address of MME for S1 connnection")
-    ("mme.dns_addr",        bpo::value<string>(&dns_addr)->default_value("8.8.8.8"),"IP address of the DNS server for the UEs")
+    ("mme.dns_addr",        bpo::value<string>(&dns_addr)->default_value("8.8.8.8"),         "IP address of the DNS server for the UEs")
     ("mme.apn",             bpo::value<string>(&mme_apn)->default_value(""),                 "Set Access Point Name (APN) for data services")
-    ("hss.db_file",         bpo::value<string>(&hss_db_file)->default_value("ue_db.csv"),".csv file that stores UE's keys")
+    ("hss.db_file",         bpo::value<string>(&hss_db_file)->default_value("ue_db.csv"),    ".csv file that stores UE's keys")
-    ("hss.auth_algo",       bpo::value<string>(&hss_auth_algo)->default_value("milenage"),"HSS uthentication algorithm.")
+    ("hss.auth_algo",       bpo::value<string>(&hss_auth_algo)->default_value("milenage"),   "HSS uthentication algorithm.")
-    ("spgw.gtpu_bind_addr", bpo::value<string>(&spgw_bind_addr)->default_value("127.0.0.1"),"IP address of SP-GW for the S1-U connection")
+    ("spgw.gtpu_bind_addr", bpo::value<string>(&spgw_bind_addr)->default_value("127.0.0.1"), "IP address of SP-GW for the S1-U connection")
-    ("spgw.sgi_if_addr",    bpo::value<string>(&sgi_if_addr)->default_value("176.16.0.1"),"IP address of TUN interface for the SGi connection")
+    ("spgw.sgi_if_addr",    bpo::value<string>(&sgi_if_addr)->default_value("176.16.0.1"),   "IP address of TUN interface for the SGi connection")
+
+    ("pcap.enable",         bpo::value<bool>(&args->mme_args.s1ap_args.pcap_enable)->default_value(false),         "Enable S1AP PCAP")
+    ("pcap.filename",       bpo::value<string>(&args->mme_args.s1ap_args.pcap_filename)->default_value("/tmp/epc.pcap"), "PCAP filename")
 
     ("log.s1ap_level",      bpo::value<string>(&args->log_args.s1ap_level),   "MME S1AP log level")
     ("log.s1ap_hex_limit",  bpo::value<int>(&args->log_args.s1ap_hex_limit),  "MME S1AP log hex dump limit")

srsepc/src/mme/s1ap.cc

@@ -100,8 +100,12 @@ s1ap::init(s1ap_args_t s1ap_args, srslte::log_filter *s1ap_log, hss_interface_s1
   m_s1mme = enb_listen();
 
   //Init PCAP
-  m_pcap.open("/tmp/epc.pcap");
+  m_pcap_enable = s1ap_args.pcap_enable;
+  if(m_pcap_enable)
+  {
+    m_pcap.open(s1ap_args.pcap_filename.c_str());
     m_s1ap_log->info("S1AP Initialized\n");
+  }
   return 0;
 }
 
@@ -134,7 +138,10 @@ s1ap::stop()
   s1ap_ctx_mngmt_proc::cleanup();
 
   //PCAP
+  if(m_pcap_enable)
+  {
     m_pcap.close();
+  }
   return;
 }
 
@@ -213,7 +220,9 @@ s1ap::handle_s1ap_rx_pdu(srslte::byte_buffer_t *pdu, struct sctp_sndrcvinfo *enb
     return false;
   }
 
+  if(m_pcap_enable){
     m_pcap.write_s1ap(pdu->msg,pdu->N_bytes);
+  }
 
   switch(rx_pdu.choice_type) {
   case LIBLTE_S1AP_S1AP_PDU_CHOICE_INITIATINGMESSAGE: