cu_cp: add unittest for initial context setup routine

Author: FabianEckermann

tests/test_doubles/ngap/ngap_test_message_validators.cpp

@@ -34,6 +34,13 @@ bool srsran::test_helpers::is_valid_initial_context_setup_response(const srs_cu_
   return true;
 }
 
+bool srsran::test_helpers::is_valid_initial_context_setup_failure(const srs_cu_cp::ngap_message& msg)
+{
+  TRUE_OR_RETURN(msg.pdu.type() == asn1::ngap::ngap_pdu_c::types_opts::unsuccessful_outcome);
+  TRUE_OR_RETURN(msg.pdu.unsuccessful_outcome().proc_code == ASN1_NGAP_ID_INIT_CONTEXT_SETUP);
+  return true;
+}
+
 bool srsran::test_helpers::is_valid_ue_context_release_request(const srs_cu_cp::ngap_message& msg)
 {
   TRUE_OR_RETURN(msg.pdu.type() == asn1::ngap::ngap_pdu_c::types_opts::init_msg);

tests/test_doubles/ngap/ngap_test_message_validators.h

@@ -24,6 +24,8 @@ bool is_valid_init_ue_message(const srs_cu_cp::ngap_message& msg);
 
 bool is_valid_initial_context_setup_response(const srs_cu_cp::ngap_message& msg);
 
+bool is_valid_initial_context_setup_failure(const srs_cu_cp::ngap_message& msg);
+
 bool is_valid_ue_context_release_request(const srs_cu_cp::ngap_message& msg);
 
 bool is_valid_ue_radio_capability_info_indication(const srs_cu_cp::ngap_message& msg);

tests/unittests/cu_cp/CMakeLists.txt

@@ -32,7 +32,7 @@ target_include_directories(cu_cp_test_helpers PRIVATE ${CMAKE_SOURCE_DIR})
 target_link_libraries(cu_cp_test_helpers srsran_cu_cp srsran_support srslog f1ap_test_helpers e1ap_test_helpers f1ap_asn1 ngap_asn1 e1ap_asn1)
 
 
-add_executable(cu_cp_test cu_cp_test.cpp cu_cp_connectivity_test.cpp cu_cp_setup_test.cpp cu_cp_reestablishment_test.cpp)
+add_executable(cu_cp_test cu_cp_test.cpp cu_cp_connectivity_test.cpp cu_cp_setup_test.cpp cu_cp_reestablishment_test.cpp cu_cp_initial_context_setup_test.cpp)
 set_target_properties(cu_cp_test PROPERTIES UNITY_BUILD ON)
 target_link_libraries(cu_cp_test
         cu_cp_test_helpers

tests/unittests/cu_cp/cu_cp_initial_context_setup_test.cpp

@@ -0,0 +1,318 @@
+/*
+ *
+ * Copyright 2021-2024 Software Radio Systems Limited
+ *
+ * By using this file, you agree to the terms and conditions set
+ * forth in the LICENSE file which can be found at the top level of
+ * the distribution.
+ *
+ */
+
+#include "cu_cp_test_environment.h"
+#include "tests/test_doubles/f1ap/f1ap_test_message_validators.h"
+#include "tests/test_doubles/f1ap/f1ap_test_messages.h"
+#include "tests/test_doubles/ngap/ngap_test_message_validators.h"
+#include "tests/test_doubles/rrc/rrc_test_message_validators.h"
+#include "tests/test_doubles/rrc/rrc_test_messages.h"
+#include "tests/unittests/e1ap/common/e1ap_cu_cp_test_messages.h"
+#include "tests/unittests/f1ap/common/f1ap_cu_test_messages.h"
+#include "tests/unittests/ngap/ngap_test_messages.h"
+#include "srsran/e1ap/common/e1ap_types.h"
+#include "srsran/f1ap/common/f1ap_message.h"
+#include "srsran/ngap/ngap_message.h"
+#include <gtest/gtest.h>
+
+using namespace srsran;
+using namespace srs_cu_cp;
+
+class cu_cp_initial_context_setup_test : public cu_cp_test_environment, public ::testing::Test
+{
+public:
+  cu_cp_initial_context_setup_test() : cu_cp_test_environment(cu_cp_test_env_params{8, 8, 8192, create_mock_amf()})
+  {
+    // Run NG setup to completion.
+    run_ng_setup();
+
+    // Setup DU.
+    std::optional<unsigned> ret = connect_new_du();
+    EXPECT_TRUE(ret.has_value());
+    du_idx = ret.value();
+    EXPECT_TRUE(this->run_f1_setup(du_idx));
+
+    // Setup CU-UP.
+    ret = connect_new_cu_up();
+    EXPECT_TRUE(ret.has_value());
+    cu_up_idx = ret.value();
+    EXPECT_TRUE(this->run_e1_setup(cu_up_idx));
+
+    // Connect UE 0x4601.
+    EXPECT_TRUE(connect_new_ue(du_idx, du_ue_id, crnti));
+    EXPECT_TRUE(authenticate_ue(du_idx, du_ue_id, amf_ue_id_t::min));
+
+    ue_ctx = this->find_ue_context(du_idx, du_ue_id);
+
+    EXPECT_NE(ue_ctx, nullptr);
+  }
+
+  void send_initial_context_setup_request(bool with_pdu_sessions = false)
+  {
+    srsran_assert(not this->get_amf().try_pop_rx_pdu(ngap_pdu), "there are still NGAP messages to pop from AMF");
+    srsran_assert(not this->get_du(du_idx).try_pop_dl_pdu(f1ap_pdu), "there are still F1AP DL messages to pop from DU");
+
+    // Inject NGAP Initial Context Setup Request
+    ngap_message init_ctxt_setup_req;
+    if (with_pdu_sessions) {
+      init_ctxt_setup_req = generate_valid_initial_context_setup_request_message_with_pdu_session(
+          ue_ctx->amf_ue_id.value(), ue_ctx->ran_ue_id.value());
+    } else {
+      init_ctxt_setup_req =
+          generate_valid_initial_context_setup_request_message(ue_ctx->amf_ue_id.value(), ue_ctx->ran_ue_id.value());
+    }
+
+    get_amf().push_tx_pdu(init_ctxt_setup_req);
+  }
+
+  void send_ue_context_setup_request_and_await_response()
+  {
+    // Wait for F1AP UE Context Setup Request (containing Security Mode Command).
+    bool result = this->wait_for_f1ap_tx_pdu(du_idx, f1ap_pdu);
+    report_fatal_error_if_not(result, "Failed to receive Security Mode Command");
+    report_fatal_error_if_not(test_helpers::is_valid_ue_context_setup_request(f1ap_pdu),
+                              "Invalid UE Context Setup Request");
+    const byte_buffer& rrc_container = test_helpers::get_rrc_container(f1ap_pdu);
+    report_fatal_error_if_not(
+        test_helpers::is_valid_rrc_security_mode_command(test_helpers::extract_dl_dcch_msg(rrc_container)),
+        "Invalid Security Mode command");
+
+    // Inject UE Context Setup Response
+    f1ap_message ue_ctxt_setup_response = generate_ue_context_setup_response(ue_ctx->cu_ue_id.value(), du_ue_id);
+    get_du(du_idx).push_ul_pdu(ue_ctxt_setup_response);
+  }
+
+  void send_security_mode_complete_and_await_ue_capability_enquiry()
+  {
+    // Inject Security Mode Complete
+    f1ap_message ul_rrc_msg_transfer = generate_ul_rrc_message_transfer(
+        ue_ctx->cu_ue_id.value(), du_ue_id, srb_id_t::srb1, make_byte_buffer("00032a00fd5ec7ff").value());
+    get_du(du_idx).push_ul_pdu(ul_rrc_msg_transfer);
+
+    // Wait for UE Capability Enquiry
+    bool result = this->wait_for_f1ap_tx_pdu(du_idx, f1ap_pdu);
+    report_fatal_error_if_not(result, "Failed to receive DL RRC Message, containing RRC UE Capability Enquiry");
+    report_fatal_error_if_not(test_helpers::is_valid_dl_rrc_message_transfer(f1ap_pdu),
+                              "Invalid DL RRC Message Transfer");
+  }
+
+  void send_ue_capability_info_and_await_registration_accept_and_initial_context_setup_response()
+  {
+    // Inject UL RRC Message Transfer (containing UE Capability Info)
+    get_du(du_idx).push_ul_pdu(test_helpers::create_ul_rrc_message_transfer(
+        du_ue_id,
+        ue_ctx->cu_ue_id.value(),
+        srb_id_t::srb1,
+        make_byte_buffer(
+            "00044c821930680ce811d1968097e360e1480005824c5c00060fc2c00637fe002e00131401a0000000880058d006007"
+            "a071e439f0000240400e0300000000100186c0000700809df000000000000030368000800004b2ca000a07143c001c0"
+            "03c000000100200409028098a8660c")
+            .value()));
+
+    // Wait for DL RRC Message Transfer (containing NAS Registration Accept)
+    bool result = this->wait_for_f1ap_tx_pdu(du_idx, f1ap_pdu);
+    report_fatal_error_if_not(result, "Failed to receive DL RRC Message, containing NAS Registration Accept");
+    report_fatal_error_if_not(test_helpers::is_valid_dl_rrc_message_transfer(f1ap_pdu),
+                              "Invalid DL RRC Message Transfer");
+
+    // Wait for Initial Context Setup Response
+    result = this->wait_for_ngap_tx_pdu(ngap_pdu);
+    report_fatal_error_if_not(result, "Failed to receive Initial Context Setup Response");
+    report_fatal_error_if_not(test_helpers::is_valid_initial_context_setup_response(ngap_pdu),
+                              "Invalid init ctxt setup");
+  }
+
+  void send_ue_capability_info_and_handle_pdu_session_resource_setup_request()
+  {
+    // Inject UL RRC Message Transfer (containing UE Capability Info)
+    get_du(du_idx).push_ul_pdu(test_helpers::create_ul_rrc_message_transfer(
+        du_ue_id,
+        ue_ctx->cu_ue_id.value(),
+        srb_id_t::srb1,
+        make_byte_buffer(
+            "00044c821930680ce811d1968097e360e1480005824c5c00060fc2c00637fe002e00131401a0000000880058d006007"
+            "a071e439f0000240400e0300000000100186c0000700809df000000000000030368000800004b2ca000a07143c001c0"
+            "03c000000100200409028098a8660c")
+            .value()));
+
+    // Wait for E1AP Bearer Context Setup Request
+    bool result = this->wait_for_e1ap_tx_pdu(0, e1ap_pdu);
+    report_fatal_error_if_not(result, "Failed to receive E1AP Bearer Context Setup Request");
+
+    cu_cp_e1ap_id =
+        int_to_gnb_cu_cp_ue_e1ap_id(e1ap_pdu.pdu.init_msg().value.bearer_context_setup_request()->gnb_cu_cp_ue_e1ap_id);
+    cu_up_e1ap_id = int_to_gnb_cu_up_ue_e1ap_id(0);
+
+    // Inject Bearer Context Setup Response and wait for F1AP UE Context Modification Request.
+    get_cu_up(0).push_tx_pdu(generate_bearer_context_setup_response(cu_cp_e1ap_id, cu_up_e1ap_id));
+    result = this->wait_for_f1ap_tx_pdu(du_idx, f1ap_pdu);
+    report_fatal_error_if_not(result, "Failed to receive F1AP UE Context Modification Request");
+    report_fatal_error_if_not(test_helpers::is_valid_ue_context_modification_request(f1ap_pdu),
+                              "Invalid UE Context Modification");
+
+    // Inject UE Context Modification Response and wait for Bearer Context Modification to be sent to CU-UP.
+    get_du(du_idx).push_ul_pdu(
+        test_helpers::generate_ue_context_modification_response(du_ue_id, ue_ctx->cu_ue_id.value(), crnti));
+    result = this->wait_for_e1ap_tx_pdu(0, e1ap_pdu);
+    report_fatal_error_if_not(result, "Failed to receive E1AP Bearer Context Modification");
+
+    // Inject E1AP Bearer Context Modification Response and wait for DL RRC Message (containing RRC Reconfiguration)
+    get_cu_up(0).push_tx_pdu(generate_bearer_context_modification_response(cu_cp_e1ap_id, cu_up_e1ap_id));
+    result = this->wait_for_f1ap_tx_pdu(du_idx, f1ap_pdu);
+    report_fatal_error_if_not(result, "Failed to receive F1AP DL RRC Message (containing RRC Reconfiguration)");
+    report_fatal_error_if_not(test_helpers::is_valid_dl_rrc_message_transfer(f1ap_pdu),
+                              "Invalid DL RRC Message Transfer");
+  }
+
+  void send_rrc_reconfiguration_complete_and_await_initial_context_setup_response()
+  {
+    // Inject UL RRC Message Transfer (containing RRC Reconfiguration Complete)
+    f1ap_message ul_rrc_msg_transfer = generate_ul_rrc_message_transfer(
+        ue_ctx->cu_ue_id.value(), du_ue_id, srb_id_t::srb1, make_byte_buffer("00050e00a18bc2b3").value());
+    get_du(du_idx).push_ul_pdu(ul_rrc_msg_transfer);
+
+    // Wait for Initial Context Setup Response
+    bool result = this->wait_for_ngap_tx_pdu(ngap_pdu);
+    report_fatal_error_if_not(result, "Failed to receive Initial Context Setup Response");
+    report_fatal_error_if_not(test_helpers::is_valid_initial_context_setup_response(ngap_pdu),
+                              "Invalid init ctxt setup");
+  }
+
+  void await_initial_context_setup_failure()
+  {
+    // Wait for NGAP Initial Context Setup Failure
+    bool result = this->wait_for_ngap_tx_pdu(ngap_pdu);
+    report_fatal_error_if_not(result, "Failed to receive Initial Context Setup Failure");
+    report_fatal_error_if_not(test_helpers::is_valid_initial_context_setup_failure(ngap_pdu),
+                              "Invalid Initial Context Setup Failure");
+  }
+
+  void await_ue_capability_info_indication()
+  {
+    // Wait for UE Capability Info Indication
+    bool result = this->wait_for_ngap_tx_pdu(ngap_pdu);
+    report_fatal_error_if_not(result, "Failed to receive UE Radio Capability Info Indication");
+    report_fatal_error_if_not(test_helpers::is_valid_ue_radio_capability_info_indication(ngap_pdu),
+                              "Invalid UE Radio Capability Info Indication");
+  }
+
+  void await_ue_context_release_request()
+  {
+    // Wait for UE Context Release Request
+    bool result = this->wait_for_ngap_tx_pdu(ngap_pdu);
+    report_fatal_error_if_not(result, "Failed to receive UE Context Release Request");
+    report_fatal_error_if_not(test_helpers::is_valid_ue_context_release_request(ngap_pdu),
+                              "Invalid UE Context Release Request");
+  }
+
+  unsigned du_idx    = 0;
+  unsigned cu_up_idx = 0;
+
+  gnb_du_ue_f1ap_id_t    du_ue_id = int_to_gnb_du_ue_f1ap_id(0);
+  rnti_t                 crnti    = to_rnti(0x4601);
+  gnb_cu_cp_ue_e1ap_id_t cu_cp_e1ap_id;
+  gnb_cu_up_ue_e1ap_id_t cu_up_e1ap_id;
+
+  const ue_context* ue_ctx = nullptr;
+
+  ngap_message ngap_pdu;
+  f1ap_message f1ap_pdu;
+  e1ap_message e1ap_pdu;
+};
+
+TEST_F(cu_cp_initial_context_setup_test, when_ue_context_setup_fails_then_initial_context_setup_fails)
+{
+  // Inject Initial Context Setup Request
+  send_initial_context_setup_request();
+
+  // Inject UE Context Setup Failure
+  f1ap_message ue_ctxt_setup_failure =
+      generate_ue_context_setup_failure(find_ue_context(du_idx, du_ue_id)->cu_ue_id.value(), du_ue_id);
+  get_du(du_idx).push_ul_pdu(ue_ctxt_setup_failure);
+
+  // Wait for NGAP Initial Context Setup Failure
+  await_initial_context_setup_failure();
+}
+
+TEST_F(cu_cp_initial_context_setup_test, when_security_mode_command_fails_then_initial_context_setup_fails)
+{
+  // Inject Initial Context Setup Request
+  send_initial_context_setup_request();
+
+  // Wait for F1AP UE Context Setup Request (containing Security Mode Command) and inject UE Context Setup Response
+  send_ue_context_setup_request_and_await_response();
+
+  // Inject Security Mode Failure
+  f1ap_message ul_rrc_msg_transfer = generate_ul_rrc_message_transfer(
+      ue_ctx->cu_ue_id.value(), du_ue_id, srb_id_t::srb1, make_byte_buffer("00033200c1bf019d").value());
+  get_du(du_idx).push_ul_pdu(ul_rrc_msg_transfer);
+
+  // Wait for NGAP Initial Context Setup Failure
+  await_initial_context_setup_failure();
+}
+
+TEST_F(cu_cp_initial_context_setup_test, when_ue_capability_enquiry_fails_then_initial_context_setup_fails)
+{
+  // Inject Initial Context Setup Request
+  send_initial_context_setup_request();
+
+  // Wait for F1AP UE Context Setup Request (containing Security Mode Command) and inject UE Context Setup Response
+  send_ue_context_setup_request_and_await_response();
+
+  // Inject Security Mode Complete and await UE Capability Enquiry
+  send_security_mode_complete_and_await_ue_capability_enquiry();
+
+  // Fail UE Capability Enquiry (UE doesn't respond)
+  ASSERT_FALSE(tick_until(std::chrono::milliseconds(this->get_cu_cp_cfg().rrc_config.rrc_procedure_timeout_ms),
+                          [&]() { return false; }));
+
+  // Wait for NGAP Initial Context Setup Failure
+  await_initial_context_setup_failure();
+}
+
+TEST_F(cu_cp_initial_context_setup_test, when_ue_capability_enquiry_successful_then_initial_context_setup_succeeds)
+{
+  // Inject Initial Context Setup Request
+  send_initial_context_setup_request();
+
+  // Wait for F1AP UE Context Setup Request (containing Security Mode Command) and inject UE Context Setup Response
+  send_ue_context_setup_request_and_await_response();
+
+  // Inject Security Mode Complete and await UE Capability Enquiry
+  send_security_mode_complete_and_await_ue_capability_enquiry();
+
+  // Inject UE Capability Info and await DL RRC Message (Registration Accept) and Initial Context Setup Response
+  send_ue_capability_info_and_await_registration_accept_and_initial_context_setup_response();
+
+  // Wait for UE Capability Info Indication
+  await_ue_capability_info_indication();
+}
+
+TEST_F(cu_cp_initial_context_setup_test,
+       when_initial_context_setup_contains_valid_pdu_sessions_to_setup_then_initial_context_setup_succeeds)
+{
+  // Inject Initial Context Setup Request
+  send_initial_context_setup_request(true);
+
+  // Wait for F1AP UE Context Setup Request (containing Security Mode Command) and inject UE Context Setup Response
+  send_ue_context_setup_request_and_await_response();
+
+  // Inject Security Mode Complete and await UE Capability Enquiry
+  send_security_mode_complete_and_await_ue_capability_enquiry();
+
+  // Inject UE Capability Info and handle PDU Session Resource Setup List Context Request
+  send_ue_capability_info_and_handle_pdu_session_resource_setup_request();
+
+  // Inject RRC Reconfiguration Complete and await Initial Context Setup Response
+  send_rrc_reconfiguration_complete_and_await_initial_context_setup_response();
+
+  // Wait for UE Capability Info Indication
+  await_ue_capability_info_indication();
+}