[test] verify state bitmap when runtime enable/disable EphemeralKey mode (#10503)

Meshcop ePSKc mode supported bitmap check.

tests/scripts/thread-cert/border_router/test_publish_meshcop_service.py

@@ -95,8 +95,20 @@ class PublishMeshCopService(thread_cert.TestCase):
         br1.start()
         self.simulator.go(config.BORDER_ROUTER_STARTUP_DELAY)
         self.assertEqual('leader', br1.get_state())
+
+        # start to test ephemeral key mode (ePSKc)
+        br1.ephemeral_key_enabled = True
+        self.assertTrue(br1.ephemeral_key_enabled)
+        self.simulator.go(10)
         self.check_meshcop_service(br1, host)
 
+        # change ephemeral key mode (ePSKc) and check Meshcop
+        br1.ephemeral_key_enabled = False
+        self.assertFalse(br1.ephemeral_key_enabled)
+        self.simulator.go(10)
+        self.check_meshcop_service(br1, host)
+        # end of ephemeral key mode (ePSKc) test
+
         br1.disable_backbone_router()
         self.simulator.go(10)
         self.check_meshcop_service(br1, host)
@@ -201,6 +213,7 @@ class PublishMeshCopService(thread_cert.TestCase):
                          br.get_backbone_router_state() != 'Disabled')  # BBR is enabled or not
         self.assertEqual((state_bitmap >> 8 & 1), device_role not in ['disabled', 'detached'] and
                          br.get_backbone_router_state() == 'Primary')  # BBR is primary or not
+        self.assertEqual(bool(state_bitmap >> 11 & 1), br.ephemeral_key_enabled)  # ePSKc is supported or not
         self.assertEqual(service_data['txt']['nn'], br.get_network_name())
         self.assertEqual(service_data['txt']['rv'], '1')
         self.assertIn(service_data['txt']['tv'], ['1.1.0', '1.1.1', '1.2.0', '1.3.0'])

tests/scripts/thread-cert/node.py

@@ -491,6 +491,16 @@ class OtbrDocker:
             raise ValueError("dns_upstream_query_state must be a bool")
         return self.set_dbus_property('DnsUpstreamQueryState', value)
 
+    @property
+    def ephemeral_key_enabled(self):
+        return bool(self.get_dbus_property('EphemeralKeyEnabled'))
+
+    @ephemeral_key_enabled.setter
+    def ephemeral_key_enabled(self, value):
+        if type(value) is not bool:
+            raise ValueError("ephemeral_key_enabled must be a bool")
+        return self.set_dbus_property('EphemeralKeyEnabled', value)
+
     def read_border_routing_counters_delta(self):
         old_counters = self._border_routing_counters
         new_counters = self.get_border_routing_counters()