[nexus] add test 5.7.1 CoAP Diagnostic Get, Response, and Reset (#12456)

This commit adds a new Nexus test case for 'CoAP Diagnostic Get
Request, Response and Reset Commands' (5.7.1) as specified in the
test specification.

Summary of changes:
- Implemented Nexus test 5.7.1:
    - Added test_5_7_1.cpp: Sets up a network topology with a Leader,
      Router 1 (DUT), and various child nodes (FED, MED, SED, REED).
      Executes the 8-step test sequence by sending CoAP Diagnostic
      Get and Reset commands from the Leader to the DUT using direct
      method calls. Uses AllowList for topology management and sets
      log level to note.
    - Added verify_5_7_1.py: PCAP verification script for test 5.7.1.
      Validates the presence and values of requested Network
      Diagnostic TLVs in CoAP requests and responses. Ensures the
      DUT correctly handles requests for MAC Counters, Timeout
      (omitted), and Child Table, and verifies the reset functionality.
- Enhanced verification utilities:
    - Updated verify_utils.py: Added length checks during Thread TLV
      parsing in CoAP payloads to handle overlapping TLV types
      correctly and prevent verification failures.
- Updated build and execution scripts:
    - Modified CMakeLists.txt to build the new 5.7.1 test executable.
    - Updated run_nexus_tests.sh to include 5.7.1 in the default test
      list.

tests/nexus/CMakeLists.txt

@@ -155,6 +155,7 @@ ot_nexus_test(5_5_4_1 "cert;nexus")
 ot_nexus_test(5_5_4_2 "cert;nexus")
 ot_nexus_test(5_5_5 "cert;nexus")
 ot_nexus_test(5_5_7 "cert;nexus")
+ot_nexus_test(5_7_1 "cert;nexus")
 ot_nexus_test(5_8_2 "cert;nexus")
 ot_nexus_test(6_1_1 "cert;nexus")
 

tests/nexus/run_nexus_tests.sh

@@ -85,6 +85,7 @@ DEFAULT_TESTS=(
     "5_5_4_2"
     "5_5_5"
     "5_5_7"
+    "5_7_1"
     "5_8_2"
     "6_1_1_A"
     "6_1_1_B"

tests/nexus/test_5_7_1.cpp

@@ -0,0 +1,305 @@
+/*
+ *  Copyright (c) 2026, The OpenThread Authors.
+ *  All rights reserved.
+ *
+ *  Redistribution and use in source and binary forms, with or without
+ *  modification, are permitted provided that the following conditions are met:
+ *  1. Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ *  2. Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *  3. Neither the name of the copyright holder nor the
+ *     names of its contributors may be used to endorse or promote products
+ *     derived from this software without specific prior written permission.
+ *
+ *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ *  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ *  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ *  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ *  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ *  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ *  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ *  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ *  POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <stdio.h>
+
+#include "platform/nexus_core.hpp"
+#include "platform/nexus_node.hpp"
+#include "thread/network_diagnostic.hpp"
+
+namespace ot {
+namespace Nexus {
+
+/**
+ * Time to advance for a node to form a network and become leader, in milliseconds.
+ */
+static constexpr uint32_t kFormNetworkTime = 13 * 1000;
+
+/**
+ * Time to advance for a node to join as a child and upgrade to a router, in milliseconds.
+ */
+static constexpr uint32_t kAttachToRouterTime = 200 * 1000;
+
+/**
+ * Time to advance for the network to stabilize after nodes have attached.
+ */
+static constexpr uint32_t kStabilizationTime = 10 * 1000;
+
+/**
+ * Time to advance for the diagnostic response to be received.
+ */
+static constexpr uint32_t kDiagResponseTime = 5 * 1000;
+
+void Test5_7_1(void)
+{
+    /**
+     * 5.7.1 CoAP Diagnostic Get Request, Response and Reset Commands
+     *
+     * 5.7.1.1 Topology
+     * - Topology A
+     * - Topology B
+     *
+     * 5.7.1.2 Purpose & Description
+     * These cases test the Diagnostic Get and Reset Commands as a part of the Network Management.
+     *
+     * Spec Reference      | V1.1 Section | V1.3.0 Section
+     * --------------------|--------------|---------------
+     * Diagnostic Commands | 10.11.2      | 10.11.2
+     */
+
+    Core nexus;
+
+    Node &dut    = nexus.CreateNode();
+    Node &leader = nexus.CreateNode();
+    Node &fed1   = nexus.CreateNode();
+    Node &med1   = nexus.CreateNode();
+    Node &sed1   = nexus.CreateNode();
+    Node &reed1  = nexus.CreateNode();
+
+    dut.SetName("DUT");
+    leader.SetName("LEADER");
+    fed1.SetName("FED_1");
+    med1.SetName("MED_1");
+    sed1.SetName("SED_1");
+    reed1.SetName("REED_1");
+
+    nexus.AdvanceTime(0);
+
+    Instance::SetLogLevel(kLogLevelNote);
+
+    /**
+     * Step 1: All
+     * - Description: Ensure topology is formed correctly.
+     * - Pass Criteria: N/A
+     */
+    Log("Step 1: All");
+
+    /** Use AllowList to specify links between nodes. */
+    dut.AllowList(leader);
+    dut.AllowList(fed1);
+    dut.AllowList(med1);
+    dut.AllowList(sed1);
+    dut.AllowList(reed1);
+
+    leader.AllowList(dut);
+    fed1.AllowList(dut);
+    med1.AllowList(dut);
+    sed1.AllowList(dut);
+    reed1.AllowList(dut);
+
+    leader.Form();
+    nexus.AdvanceTime(kFormNetworkTime);
+
+    dut.Join(leader);
+    nexus.AdvanceTime(kAttachToRouterTime);
+
+    VerifyOrQuit(dut.Get<Mle::Mle>().IsRouter());
+
+    fed1.Join(dut, Node::kAsFed);
+    med1.Join(dut, Node::kAsMed);
+    sed1.Join(dut, Node::kAsSed);
+    reed1.Join(dut, Node::kAsFtd);
+
+    nexus.AdvanceTime(kAttachToRouterTime);
+    nexus.AdvanceTime(kStabilizationTime);
+
+    const Ip6::Address &dutRloc = dut.Get<Mle::Mle>().GetMeshLocalRloc();
+
+    /**
+     * Step 2: Leader
+     * - Description: Harness instructs the device to send DIAG_GET.req to the DUT’s Routing Locator (RLOC) for the
+     *   following diagnostic TLV types:
+     *   - TLV Type 0 – MAC Extended Address (64-bit)
+     *   - TLV Type 1 - MAC Address (16-bit)
+     *   - TLV Type 2 - Mode (Capability information)
+     *   - TLV Type 4 – Connectivity
+     *   - TLV Type 5 – Route64
+     *   - TLV Type 6 – Leader Data
+     *   - TLV Type 7 – Network Data
+     *   - TLV Type 8 – IPv6 address list
+     *   - TLV Type 17 – Channel Pages
+     * - Pass Criteria:
+     *   - The DUT MUST respond with a DIAG_GET.rsp response containing the requested diagnostic TLVs:
+     *   - CoAP Response Code: 2.04 Changed
+     *   - CoAP Payload:
+     *     - TLV Type 0 - MAC Extended Address (64-bit)
+     *     - TLV Type 1 - MAC Address (16-bit)
+     *     - TLV Type 2 - Mode (Capability information)
+     *     - TLV Type 4 – Connectivity
+     *     - TLV Type 5 – Route64 (required ONLY for Topology A)
+     *     - TLV Type 6 – Leader Data
+     *     - TLV Type 7 – Network Data
+     *     - TLV Type 8 – IPv6 address list
+     *     - TLV Type 17 – Channel Pages
+     *   - The presence of each TLV MUST be validated. Where possible, the value of the TLV’s MUST be validated.
+     *   - Route64 TLV MUST be omitted in Topology B.
+     */
+    Log("Step 2: Leader");
+
+    uint8_t tlvTypes2[] = {
+        NetworkDiagnostic::Tlv::kExtMacAddress, NetworkDiagnostic::Tlv::kAddress16,
+        NetworkDiagnostic::Tlv::kMode,          NetworkDiagnostic::Tlv::kConnectivity,
+        NetworkDiagnostic::Tlv::kRoute,         NetworkDiagnostic::Tlv::kLeaderData,
+        NetworkDiagnostic::Tlv::kNetworkData,   NetworkDiagnostic::Tlv::kIp6AddressList,
+        NetworkDiagnostic::Tlv::kChannelPages,
+    };
+
+    SuccessOrQuit(leader.Get<NetworkDiagnostic::Client>().SendDiagnosticGet(dutRloc, tlvTypes2, sizeof(tlvTypes2),
+                                                                            nullptr, nullptr));
+    nexus.AdvanceTime(kDiagResponseTime);
+
+    /**
+     * Step 3: Leader
+     * - Description: Harness instructs the device to send DIAG_GET.req to the DUT’s Routing Locator (RLOC) for the
+     *   following diagnostic TLV type:
+     *   - TLV Type 9 - MAC Counters
+     * - Pass Criteria:
+     *   - The DUT MUST respond with a DIAG_GET.rsp response containing the requested diagnostic TLV:
+     *   - CoAP Response Code: 2.04 Changed
+     *   - CoAP Payload:
+     *     - TLV Type 9 - MAC Counters
+     *   - TLV Type 9 - MAC Counters MUST contain a list of MAC Counters.
+     */
+    Log("Step 3: Leader");
+
+    uint8_t tlvTypes3[] = {NetworkDiagnostic::Tlv::kMacCounters};
+
+    SuccessOrQuit(leader.Get<NetworkDiagnostic::Client>().SendDiagnosticGet(dutRloc, tlvTypes3, sizeof(tlvTypes3),
+                                                                            nullptr, nullptr));
+    nexus.AdvanceTime(kDiagResponseTime);
+
+    /**
+     * Step 4: Leader
+     * - Description: Harness instructs the device to send DIAG_GET.req to the DUT’s Routing Locator (RLOC) for the
+     *   following diagnostic TLV type:
+     *   - TLV Type 3 – Timeout
+     * - Pass Criteria:
+     *   - The DUT MUST respond with a DIAG_GET.rsp response containing the required diagnostic TLV payload:
+     *   - CoAP Response Code: 2.04 Changed
+     *   - CoAP Payload:
+     *     - TLV Value 3 - Timeout MUST be omitted from the response.
+     */
+    Log("Step 4: Leader");
+
+    uint8_t tlvTypes4[] = {NetworkDiagnostic::Tlv::kTimeout};
+
+    SuccessOrQuit(leader.Get<NetworkDiagnostic::Client>().SendDiagnosticGet(dutRloc, tlvTypes4, sizeof(tlvTypes4),
+                                                                            nullptr, nullptr));
+    nexus.AdvanceTime(kDiagResponseTime);
+
+    /**
+     * Step 5: Leader
+     * - Description: Harness instructs the device to send DIAG_GET.req to the DUT’s Routing Locator (RLOC) for the
+     *   following diagnostic TLV types:
+     *   - TLV Type 14 – Battery Level
+     *   - TLV Type 15 – Supply Voltage
+     * - Pass Criteria:
+     *   - The DUT MUST respond with a DIAG_GET.rsp response optionally containing the requested diagnostic TLVs:
+     *   - CoAP Response Code: 2.04 Changed
+     *   - CoAP Payload:
+     *     - TLV Type 14 – Battery Level (optional)
+     *     - TLV Type 15 – Supply Voltage (optional)
+     */
+    Log("Step 5: Leader");
+
+    uint8_t tlvTypes5[] = {NetworkDiagnostic::Tlv::kBatteryLevel, NetworkDiagnostic::Tlv::kSupplyVoltage};
+
+    SuccessOrQuit(leader.Get<NetworkDiagnostic::Client>().SendDiagnosticGet(dutRloc, tlvTypes5, sizeof(tlvTypes5),
+                                                                            nullptr, nullptr));
+    nexus.AdvanceTime(kDiagResponseTime);
+
+    /**
+     * Step 6: Leader
+     * - Description: Harness instructs the device to send DIAG_GET.req to the DUT’s Routing Locator (RLOC) for the
+     *   following diagnostic TLV type:
+     *   - TLV Type 16 – Child Table
+     * - Pass Criteria:
+     *   - For Topology A:
+     *     - CoAP Response Code: 2.04 Changed
+     *     - CoAP Payload: TLV Type 16 – Child Table. The content of the TLV MUST be correct.
+     *   - For Topology B:
+     *     - CoAP Response Code: 2.04 Changed
+     *     - CoAP Payload: Empty
+     */
+    Log("Step 6: Leader");
+
+    uint8_t tlvTypes6[] = {NetworkDiagnostic::Tlv::kChildTable};
+
+    SuccessOrQuit(leader.Get<NetworkDiagnostic::Client>().SendDiagnosticGet(dutRloc, tlvTypes6, sizeof(tlvTypes6),
+                                                                            nullptr, nullptr));
+    nexus.AdvanceTime(kDiagResponseTime);
+
+    /**
+     * Step 7: Leader
+     * - Description: Harness instructs the device to send DIAG_RST.ntf to DUT’s Routing Locator (RLOC) for the
+     *   following diagnostic TLV type:
+     *   - TLV Type 9 - MAC Counters
+     * - Pass Criteria:
+     *   - The DUT MUST respond with a CoAP response:
+     *   - CoAP Response Code: 2.04 Changed
+     */
+    Log("Step 7: Leader");
+
+    uint8_t tlvTypes7[] = {NetworkDiagnostic::Tlv::kMacCounters};
+
+    SuccessOrQuit(leader.Get<NetworkDiagnostic::Client>().SendDiagnosticReset(dutRloc, tlvTypes7, sizeof(tlvTypes7)));
+    nexus.AdvanceTime(kDiagResponseTime);
+
+    /**
+     * Step 8: Leader
+     * - Description: Harness instructs the device to send DIAG_GET.req to the DUT’s Routing Locator (RLOC) for the
+     *   following diagnostic TLV type:
+     *   - TLV Type 9 - MAC Counters
+     * - Pass Criteria:
+     *   - The DUT MUST respond with a DIAG_GET.rsp response containing the requested diagnostic TLV:
+     *   - CoAP Response Code: 2.04 Changed
+     *   - CoAP Payload:
+     *     - TLV Type 9 - MAC Counters
+     *   - TLV Type 9 - MAC Counters MUST contain a list of MAC Counters with 0 value or less than value returned in
+     *     step 3.
+     */
+    Log("Step 8: Leader");
+
+    uint8_t tlvTypes8[] = {NetworkDiagnostic::Tlv::kMacCounters};
+
+    SuccessOrQuit(leader.Get<NetworkDiagnostic::Client>().SendDiagnosticGet(dutRloc, tlvTypes8, sizeof(tlvTypes8),
+                                                                            nullptr, nullptr));
+    nexus.AdvanceTime(kDiagResponseTime);
+
+    nexus.SaveTestInfo("test_5_7_1.json");
+}
+
+} // namespace Nexus
+} // namespace ot
+
+int main(void)
+{
+    ot::Nexus::Test5_7_1();
+    printf("All tests passed\n");
+    return 0;
+}