Send Service Reject when there's no appropriate NAS/NGAP context

src/amf-app/amf_n1.cpp

@@ -48,6 +48,7 @@
 #include "SecurityModeComplete.hpp"
 #include "ServiceAccept.hpp"
 #include "ServiceRequest.hpp"
+#include "ServiceReject.hpp"
 #include "String2Value.hpp"
 #include "UEAuthenticationCtx.h"
 #include "ULNASTransport.hpp"
@@ -811,19 +812,28 @@ void amf_n1::service_request_handle(
     return;
   }
 
+  // If there's no appropriate context, send Service Reject
   if (!nc or !uc or !nc->security_ctx) {
     Logger::amf_n1().debug(
         "Cannot find NAS/UE context, send Service Reject to UE");
-    // TODO: service reject
-    uint8_t nas[4];
-    nas[0] = EPD_5GS_MM_MSG;
-    nas[1] = PLAIN_5GS_MSG;
-    nas[2] = SERVICE_REJECT;
-    nas[3] = _5GMM_CAUSE_UE_IDENTITY_CANNOT_BE_DERIVED;
+
+    std::unique_ptr<ServiceReject> service_reject =
+        std::make_unique<ServiceReject>();
+    service_reject->SetHeader(PLAIN_5GS_MSG);
+    service_reject->Set5gmmCause(_5GMM_CAUSE_UE_IDENTITY_CANNOT_BE_DERIVED);
+
+    uint8_t buffer[BUFFER_SIZE_512] = {0};
+    int encoded_size = service_reject->Encode(buffer, BUFFER_SIZE_512);
+    comUt::print_buffer(
+        "amf_n1", "Service-Reject message buffer", buffer, encoded_size);
+    if (!encoded_size) {
+      Logger::amf_n1().error("Encode Service-Reject message error");
+      return;
+    }
 
     std::shared_ptr<itti_dl_nas_transport> dnt =
         std::make_shared<itti_dl_nas_transport>(TASK_AMF_N1, TASK_AMF_N2);
-    dnt->nas            = blk2bstr(nas, 4);
+    dnt->nas            = blk2bstr(buffer, encoded_size);
     dnt->amf_ue_ngap_id = amf_ue_ngap_id;
     dnt->ran_ue_ngap_id = ran_ue_ngap_id;
 
@@ -836,6 +846,7 @@ void amf_n1::service_request_handle(
     return;
   }
 
+  // Otherwise, continue to process Service Request message
   set_amf_ue_ngap_id_2_nas_context(amf_ue_ngap_id, nc);
   nas_secu_ctx* secu = nc->security_ctx;  // TODO: remove naked ptr
   if (!secu) {

src/nas/common/Ie_Const.hpp

@@ -130,7 +130,7 @@ constexpr uint8_t kIeiEpsBearerContextStatus = 0x60;
 constexpr uint8_t kIeiUeRadioCapabilityId    = 0x67;
 constexpr uint8_t kIeiRejectedNssaiRr        = 0x69;
 constexpr uint8_t kIeiGprsTimer3T3324        = 0x6A;
-constexpr uint8_t kIeiGprsTimer3T3348        = 0x6B;
+constexpr uint8_t kIeiGprsTimer3T3448        = 0x6B;
 constexpr uint8_t kIeiGprsTimer3T3447        = 0x6C;
 constexpr uint8_t kIeiGprsTimer3T3512        = 0x5E;
 constexpr uint8_t kIeiGprsTimer3BackOffTimer = 0x37;

src/nas/msgs/RegistrationAccept.cpp

@@ -1155,9 +1155,9 @@ int RegistrationAccept::Decode(uint8_t* buf, int len) {
         Logger::nas_mm().debug("Next IEI (0x%x)", octet);
       } break;
 
-      case kIeiGprsTimer3T3348: {
-        Logger::nas_mm().debug("Decoding IEI 0x%x", kIeiGprsTimer3T3348);
-        GprsTimer3 ie_T3448_value_tmp(kIeiGprsTimer3T3348);
+      case kIeiGprsTimer3T3448: {
+        Logger::nas_mm().debug("Decoding IEI 0x%x", kIeiGprsTimer3T3448);
+        GprsTimer3 ie_T3448_value_tmp(kIeiGprsTimer3T3448);
         if ((decoded_result = ie_T3448_value_tmp.Decode(
                  buf + decoded_size, len - decoded_size, true)) ==
             KEncodeDecodeError) {

src/nas/msgs/ServiceAccept.cpp

@@ -242,9 +242,9 @@ int ServiceAccept::Decode(uint8_t* buf, int len) {
         Logger::nas_mm().debug("Next IEI (0x%x)", octet);
       } break;
 
-      case kIeiGprsTimer3T3348: {
-        Logger::nas_mm().debug("Decoding IEI 0x%x", kIeiGprsTimer3T3348);
-        GprsTimer3 ie_T3448_value_tmp(kIeiGprsTimer3T3348);
+      case kIeiGprsTimer3T3448: {
+        Logger::nas_mm().debug("Decoding IEI 0x%x", kIeiGprsTimer3T3448);
+        GprsTimer3 ie_T3448_value_tmp(kIeiGprsTimer3T3448);
         if ((decoded_result = ie_T3448_value_tmp.Decode(
                  buf + decoded_size, len - decoded_size, true)) ==
             KEncodeDecodeError)