First version for Get Network Slice Selection from NSSF

etc/amf.conf

@@ -114,6 +114,7 @@ AMF =
      SMF_SELECTION   = "@SMF_SELECTION@";    # Set to yes to enable SMF discovery and selection
      EXTERNAL_AUSF   = "@EXTERNAL_AUSF@";    # Set to yes if AMF works with an external AUSF
      EXTERNAL_UDM    = "@EXTERNAL_UDM@";     # Set to yes if AMF works with an external UDM
+     EXTERNAL_NSSF    = "no";     # Set to yes if AMF works with an external NSSF
      USE_FQDN_DNS    = "@USE_FQDN_DNS@";     # Set to yes if AMF relies on a DNS to resolve NRF/SMF/UDM/AUSF's FQDN
      USE_HTTP2       = "no";                 # Set to yes to enable HTTP2 for AMF server
 }

src/amf-app/amf_config.cpp

@@ -82,6 +82,7 @@ amf_config::amf_config() {
   support_features.enable_smf_selection   = false;
   support_features.enable_external_ausf   = false;
   support_features.enable_external_udm    = false;
+  support_features.enable_external_nssf   = false;
   support_features.use_fqdn_dns           = false;
   support_features.use_http2              = false;
   // TODO:
@@ -270,6 +271,14 @@ int amf_config::load(const std::string& config_file) {
       support_features.enable_external_udm = false;
     }
 
+    support_features_cfg.lookupValue(
+        AMF_CONFIG_STRING_SUPPORT_FEATURES_EXTERNAL_NSSF, opt);
+    if (boost::iequals(opt, "yes")) {
+      support_features.enable_external_nssf = true;
+    } else {
+      support_features.enable_external_nssf = false;
+    }
+
     support_features_cfg.lookupValue(
         AMF_CONFIG_STRING_SUPPORT_FEATURES_USE_FQDN_DNS, opt);
     if (boost::iequals(opt, "yes")) {
@@ -706,6 +715,9 @@ void amf_config::display() {
   Logger::config().info(
       "    External UDM ..........: %s",
       support_features.enable_external_udm ? "Yes" : "No");
+  Logger::config().info(
+      "    External NSSF .........: %s",
+      support_features.enable_external_nssf ? "Yes" : "No");
   Logger::config().info(
       "    Use FQDN ..............: %s",
       support_features.use_fqdn_dns ? "Yes" : "No");

src/amf-app/amf_config.hpp

@@ -108,6 +108,7 @@
 #define AMF_CONFIG_STRING_SUPPORT_FEATURES_SMF_SELECTION "SMF_SELECTION"
 #define AMF_CONFIG_STRING_SUPPORT_FEATURES_EXTERNAL_AUSF "EXTERNAL_AUSF"
 #define AMF_CONFIG_STRING_SUPPORT_FEATURES_EXTERNAL_UDM "EXTERNAL_UDM"
+#define AMF_CONFIG_STRING_SUPPORT_FEATURES_EXTERNAL_NSSF "EXTERNAL_NSSF"
 #define AMF_CONFIG_STRING_SUPPORT_FEATURES_USE_FQDN_DNS "USE_FQDN_DNS"
 #define AMF_CONFIG_STRING_SUPPORT_FEATURES_USE_HTTP2 "USE_HTTP2"
 
@@ -231,6 +232,7 @@ class amf_config {
     bool enable_smf_selection;
     bool enable_external_ausf;
     bool enable_external_udm;
+    bool enable_external_nssf;
     bool use_fqdn_dns;
     bool use_http2;
   } support_features;

src/amf-app/amf_n1.cpp

@@ -1583,8 +1583,9 @@ bool amf_n1::_5g_aka_confirmation_from_ausf(
   Logger::amf_n1().debug("_5g_aka_confirmation_from_ausf");
   std::string remoteUri = nc.get()->Href;
 
-  std::string msgBody        = {};
-  std::string response       = {};
+  std::string msgBody = {};
+  // std::string response       = {};
+  nlohmann::json response    = {};
   std::string resStar_string = {};
 
   std::map<std::string, std::string>::iterator iter;
@@ -1619,7 +1620,8 @@ bool amf_n1::_5g_aka_confirmation_from_ausf(
   free_wrapper((void**) &resStar_s);
   try {
     ConfirmationDataResponse confirmationdataresponse;
-    nlohmann::json::parse(response.c_str()).get_to(confirmationdataresponse);
+    // nlohmann::json::parse(response.c_str()).get_to(confirmationdataresponse);
+    response.get_to(confirmationdataresponse);
     unsigned char* kseaf_hex =
         conv::format_string_as_hex(confirmationdataresponse.getKseaf());
     memcpy(nc.get()->_5g_av[0].kseaf, kseaf_hex, 32);
@@ -3707,8 +3709,8 @@ bool amf_n1::reroute_registration_request(std::shared_ptr<nas_context>& nc) {
       "Registration with AMF re-allocation, Reroute Registration Request to "
       "the target AMF");
   nssai_t nssai = {};
-  if (!get_slice_selection_subscription_data(nc, nssai)) {  // Get NSSAI from
-                                                            // UDM
+  // Get NSSAI from UDM
+  if (!get_slice_selection_subscription_data(nc, nssai)) {
     return false;
   }
   // Check that AMF can process the Requested NSSAIs or not
@@ -3772,7 +3774,7 @@ bool amf_n1::get_slice_selection_subscription_data(
     int ret = itti_inst->send_msg(itti_msg);
     if (0 != ret) {
       Logger::ngap().error(
-          "Could not send ITTI message %s to task TASK_AMF_N2",
+          "Could not send ITTI message %s to task TASK_AMF_N11",
           itti_msg->get_msg_name());
     }
 
@@ -3784,10 +3786,10 @@ bool amf_n1::get_slice_selection_subscription_data(
       assert(f.is_ready());
       assert(f.has_value());
       assert(!f.has_exception());
-      // Wait for the result from APP and send reply to AMF
+      // Wait for the result from UDM
       nlohmann::json nssai = f.get();
       if (!nssai.empty()) {
-        Logger::ngap().debug("Got NSSAI from UDM", nssai.dump().c_str());
+        Logger::ngap().debug("Got NSSAI from UDM: %s", nssai.dump().c_str());
       } else {
         return false;
       }
@@ -3809,17 +3811,80 @@ bool amf_n1::get_slice_selection_subscription_data_from_conf_file(
   // TODO:
   return true;
 }
+
 //------------------------------------------------------------------------------
 bool amf_n1::get_network_slice_selection(
     const std::string& nf_instance_id,
     slice_info_for_registration_t& slice_info,
     authorized_network_slice_info_t& authorized_network_slice_info) const {
-  // TODO: UDM selection (from NRF or configuration file)
-  if (amf_cfg.support_features.enable_external_udm) {
+  if (amf_cfg.support_features.enable_external_nssf) {
+    // Get Authorized Network Slice Info from an  external NSSF
+
+    std::shared_ptr<itti_n11_network_slice_selection_information> itti_msg =
+        std::make_shared<itti_n11_network_slice_selection_information>(
+            TASK_AMF_N1, TASK_AMF_N11);
+
+    // Generate a promise and associate this promise to the ITTI message
+    uint32_t promise_id = amf_app_inst->generate_promise_id();
+    Logger::amf_n1().debug("Promise ID generated %d", promise_id);
+
+    boost::shared_ptr<boost::promise<nlohmann::json>> p =
+        boost::make_shared<boost::promise<nlohmann::json>>();
+    boost::shared_future<nlohmann::json> f = p->get_future();
+    amf_app_inst->add_promise(promise_id, p);
+
+    itti_msg->http_version   = 1;
+    itti_msg->nf_instance_id = nf_instance_id;
+    itti_msg->slice_info     = slice_info;
+    itti_msg->promise_id     = promise_id;
+
+    int ret = itti_inst->send_msg(itti_msg);
+    if (0 != ret) {
+      Logger::ngap().error(
+          "Could not send ITTI message %s to task TASK_AMF_N11",
+          itti_msg->get_msg_name());
+    }
+
+    bool result = false;
+    boost::future_status status;
+    // wait for timeout or ready
+    status = f.wait_for(boost::chrono::milliseconds(FUTURE_STATUS_TIMEOUT_MS));
+    if (status == boost::future_status::ready) {
+      assert(f.is_ready());
+      assert(f.has_value());
+      assert(!f.has_exception());
+      // Wait for the result from NSSF
+      nlohmann::json network_slice_info = f.get();
+      if (!network_slice_info.empty()) {
+        Logger::ngap().debug(
+            "Got Authorized Network Slice Info from NSSF: %s",
+            network_slice_info.dump().c_str());
+      } else {
+        return false;
+      }
+
+    } else {
+      return false;
+    }
+
+  } else {
+    // TODO: Get Authorized Network Slice Info from local configuration file
+    return get_network_slice_selection_from_conf_file(
+        nf_instance_id, slice_info, authorized_network_slice_info);
   }
   return true;
 }
 
+//------------------------------------------------------------------------------
+bool amf_n1::get_network_slice_selection_from_conf_file(
+    const std::string& nf_instance_id,
+    slice_info_for_registration_t& slice_info,
+    authorized_network_slice_info_t& authorized_network_slice_info) const {
+  // TODO: Get Authorized Network Slice Info from local configuration file
+
+  return true;
+}
+
 //------------------------------------------------------------------------------
 void amf_n1::send_n1_message_notity(
     const std::shared_ptr<nas_context>& nc,

src/amf-app/amf_n1.hpp

@@ -230,6 +230,11 @@ class amf_n1 {
       const std::string& nf_instance_id,
       slice_info_for_registration_t& slice_info,
       authorized_network_slice_info_t& authorized_network_slice_info) const;
+  bool get_network_slice_selection_from_conf_file(
+      const std::string& nf_instance_id,
+      slice_info_for_registration_t& slice_info,
+      authorized_network_slice_info_t& authorized_network_slice_info) const;
+
   void send_n1_message_notity(
       const std::shared_ptr<nas_context>& nc,
       const std::string& target_amf) const;

src/amf-app/amf_n11.hpp

@@ -61,6 +61,8 @@ class amf_n11 {
   void handle_itti_message(itti_sbi_notify_subscribed_event& itti_msg);
   void handle_itti_message(
       itti_n11_slice_selection_subscription_data& itti_msg);
+  void handle_itti_message(
+      itti_n11_network_slice_selection_information& itti_msg);
 
   void send_pdu_session_update_sm_context_request(
       std::string supi, std::shared_ptr<pdu_session_context> psc,
@@ -79,8 +81,8 @@ class amf_n11 {
       uint8_t http_version = 1, uint32_t promise_id = 0);
 
   void curl_http_client(
-      std::string remoteUri, std::string Method, std::string msgBody,
-      std::string& response, uint8_t http_version = 1);
+      std::string remote_uri, std::string method, std::string msg_body,
+      nlohmann::json& response_json, uint8_t http_version = 1);
 
   bool discover_smf_from_nsi_info(
       std::string& smf_addr, std::string& smf_api_version,

src/common/3gpp_29.500.h

@@ -28,7 +28,7 @@ enum class http_response_codes_e {
   HTTP_RESPONSE_CODE_200_OK                 = 200,
   HTTP_RESPONSE_CODE_201_CREATED            = 201,
   HTTP_RESPONSE_CODE_202_ACCEPTED           = 202,
-  HTTP_RESPONSE_CODE_204_UPDATED            = 204,
+  HTTP_RESPONSE_CODE_204_NO_CONTENT         = 204,
   HTTP_RESPONSE_CODE_BAD_REQUEST            = 400,
   HTTP_RESPONSE_CODE_UNAUTHORIZED           = 401,
   HTTP_RESPONSE_CODE_FORBIDDEN              = 403,

src/itti/itti_msg.hpp

@@ -87,6 +87,7 @@ typedef enum {
   N11_UPDATE_NF_INSTANCE_RESPONSE,
   N11_DEREGISTER_NF_INSTANCE,
   N11_SLICE_SELECTION_SUBSCRIPTION_DATA,
+  N11_NETWORK_SLICE_SELECTION_INFORMATION,
   SBI_EVENT_EXPOSURE_REQUEST,
   SBI_NOTIFICATION_DATA,
   SBI_NOTIFY_SUBSCRIBED_EVENT,

src/itti/msgs/itti_msg_n11.hpp

@@ -28,6 +28,7 @@
 #include "amf_profile.hpp"
 #include "bstrlib.h"
 #include "itti_msg.hpp"
+#include "3gpp_29.531.h"
 
 class itti_msg_n11 : public itti_msg {
  public:
@@ -208,4 +209,21 @@ class itti_n11_slice_selection_subscription_data : public itti_msg_n11 {
   uint32_t promise_id;
 };
 
+//-----------------------------------------------------------------------------
+class itti_n11_network_slice_selection_information : public itti_msg_n11 {
+ public:
+  itti_n11_network_slice_selection_information(
+      const task_id_t orig, const task_id_t dest)
+      : itti_msg_n11(N11_NETWORK_SLICE_SELECTION_INFORMATION, orig, dest),
+        http_version(1) {}
+  const char* get_msg_name() {
+    return "N11_NETWORK_SLICE_SELECTION_INFORMATION";
+  };
+
+  uint8_t http_version;
+  std::string nf_instance_id;
+  slice_info_for_registration_t slice_info;
+  uint32_t promise_id;
+};
+
 #endif