[ncp] add spinel properties for border agent (#11271)

This commit adds spinel properties for border agent MeshCoP service to
work under NCP.

* `SPINEL_PROP_BORDER_AGENT_MESHCOP_SERIVCE_STATE`: this simply
  conveys the MeshCoP service state, including `IsActive`, udp port
  and the encoded Txt values.

* `SPINEL_PROP_BORDER_AGENT_MESHCOP_SERIVCE_STATE_SUBSCRIPTION`: this
  notifies the NCP side to register the state change callback. Because
  we hope that the host side can have initial values. But if we
  register the state change callback in NCP's initialization, the
  callback will be invoked at a very early stage and send the values
  while the host isn't ready to receive the MeshCoP service values. So
  this property enables the host to decide when to receive the initial
  values.

src/lib/spinel/spinel.c

@@ -1418,6 +1418,7 @@ const char *spinel_prop_key_to_cstr(spinel_prop_key_t prop_key)
         {SPINEL_PROP_DNSSD_HOST, "DNSSD_HOST"},
         {SPINEL_PROP_DNSSD_SERVICE, "DNSSD_SERVICE"},
         {SPINEL_PROP_DNSSD_KEY_RECORD, "DNSSD_KEY_RECORD"},
+        {SPINEL_PROP_BORDER_AGENT_MESHCOP_SERVICE_STATE, "BORDER_AGENT_MESHCOP_SERVICE_STATE"},
         {SPINEL_PROP_PARENT_RESPONSE_INFO, "PARENT_RESPONSE_INFO"},
         {SPINEL_PROP_SLAAC_ENABLED, "SLAAC_ENABLED"},
         {SPINEL_PROP_SUPPORTED_RADIO_LINKS, "SUPPORTED_RADIO_LINKS"},

src/lib/spinel/spinel.h

@@ -4884,6 +4884,20 @@ enum
 
     SPINEL_PROP_DNSSD__END = 0x950,
 
+    SPINEL_PROP_BORDER_AGENT__BEGIN = 0x950,
+
+    /// Border Agent MeshCoP service state.
+    /**
+     * Format: `bSD`: Get and Unsolicited notifications.
+     *
+     * `b`: Whether the border agent is running or not.
+     * `S`: The UDP port that is being used by the border agent. If the state is 'Stopped', the port MUST be 0.
+     * `D`: The encoded MeshCoP service TXT data (from Thread side).
+     */
+    SPINEL_PROP_BORDER_AGENT_MESHCOP_SERVICE_STATE = SPINEL_PROP_BORDER_AGENT__BEGIN + 1,
+
+    SPINEL_PROP_BORDER_AGENT__END = 0x970,
+
     SPINEL_PROP_NEST__BEGIN = 0x3BC0,
 
     SPINEL_PROP_NEST_STREAM_MFG = SPINEL_PROP_NEST__BEGIN + 0,

src/ncp/changed_props_set.cpp

@@ -93,6 +93,9 @@ const ChangedPropsSet::Entry ChangedPropsSet::mSupportedProps[] = {
 #endif
     {SPINEL_PROP_PARENT_RESPONSE_INFO, SPINEL_STATUS_OK, true},
     {SPINEL_PROP_THREAD_MGMT_SET_PENDING_DATASET_TLVS, SPINEL_STATUS_OK, false},
+#if OPENTHREAD_FTD && OPENTHREAD_CONFIG_BORDER_AGENT_ENABLE
+    {SPINEL_PROP_BORDER_AGENT_MESHCOP_SERVICE_STATE, SPINEL_STATUS_OK, false}
+#endif
 };
 
 uint8_t ChangedPropsSet::GetNumEntries(void) const

src/ncp/ncp_base.cpp

@@ -35,6 +35,7 @@
 #include <stdarg.h>
 #include <stdlib.h>
 
+#include <openthread/border_agent.h>
 #include <openthread/diag.h>
 #include <openthread/icmp6.h>
 #include <openthread/link.h>
@@ -367,6 +368,9 @@ NcpBase::NcpBase(Instance *aInstance)
 #if OPENTHREAD_CONFIG_MLE_PARENT_RESPONSE_CALLBACK_API_ENABLE
     otThreadRegisterParentResponseCallback(mInstance, &NcpBase::HandleParentResponseInfo, static_cast<void *>(this));
 #endif
+#if OPENTHREAD_CONFIG_BORDER_AGENT_ENABLE
+    otBorderAgentSetMeshCoPServiceChangedCallback(mInstance, HandleBorderAgentMeshCoPServiceChanged, this);
+#endif
 #endif // OPENTHREAD_FTD
 #if OPENTHREAD_CONFIG_SRP_CLIENT_ENABLE
     otSrpClientSetCallback(mInstance, HandleSrpClientCallback, this);

src/ncp/ncp_base.hpp

@@ -457,6 +457,12 @@ protected:
     static void HandleParentResponseInfo(otThreadParentResponseInfo *aInfo, void *aContext);
     void        HandleParentResponseInfo(const otThreadParentResponseInfo &aInfo);
 #endif
+
+#if OPENTHREAD_FTD && OPENTHREAD_CONFIG_BORDER_AGENT_ENABLE
+    static void HandleBorderAgentMeshCoPServiceChanged(void *aContext);
+    void        HandleBorderAgentMeshCoPServiceChanged(void);
+#endif
+
 #endif
 
     static void HandleDatagramFromStack(otMessage *aMessage, void *aContext);

src/ncp/ncp_base_dispatcher.cpp

@@ -227,6 +227,9 @@ NcpBase::PropertyHandler NcpBase::FindGetPropertyHandler(spinel_prop_key_t aKey)
 #if OPENTHREAD_CONFIG_BORDER_ROUTING_ENABLE
         OT_NCP_GET_HANDLER_ENTRY(SPINEL_PROP_SRP_SERVER_AUTO_ENABLE_MODE),
 #endif
+#if OPENTHREAD_FTD && OPENTHREAD_CONFIG_BORDER_AGENT_ENABLE
+        OT_NCP_GET_HANDLER_ENTRY(SPINEL_PROP_BORDER_AGENT_MESHCOP_SERVICE_STATE),
+#endif
 #endif
         OT_NCP_GET_HANDLER_ENTRY(SPINEL_PROP_UNSOL_UPDATE_FILTER),
         OT_NCP_GET_HANDLER_ENTRY(SPINEL_PROP_UNSOL_UPDATE_LIST),

src/ncp/ncp_base_ftd.cpp

@@ -117,7 +117,7 @@ void NcpBase::HandleParentResponseInfo(const otThreadParentResponseInfo &aInfo)
 exit:
     return;
 }
-#endif
+#endif // OPENTHREAD_CONFIG_MLE_PARENT_RESPONSE_CALLBACK_API_ENABLE
 
 void NcpBase::HandleNeighborTableChanged(otNeighborTableEvent aEvent, const otNeighborTableEntryInfo *aEntry)
 {
@@ -190,6 +190,21 @@ exit:
     }
 }
 
+#if OPENTHREAD_CONFIG_BORDER_AGENT_ENABLE
+
+void NcpBase::HandleBorderAgentMeshCoPServiceChanged(void *aContext)
+{
+    static_cast<NcpBase *>(aContext)->HandleBorderAgentMeshCoPServiceChanged();
+}
+
+void NcpBase::HandleBorderAgentMeshCoPServiceChanged(void)
+{
+    mChangedPropsSet.AddProperty(SPINEL_PROP_BORDER_AGENT_MESHCOP_SERVICE_STATE);
+    mUpdateChangedPropsTask.Post();
+}
+
+#endif // OPENTHREAD_CONFIG_BORDER_AGENT_ENABLE
+
 // ----------------------------------------------------------------------------
 // MARK: Individual Property Handlers
 // ----------------------------------------------------------------------------
@@ -1633,6 +1648,24 @@ exit:
 
 #endif // OPENTHREAD_CONFIG_NCP_DNSSD_ENABLE && OPENTHREAD_CONFIG_PLATFORM_DNSSD_ENABLE
 
+#if OPENTHREAD_CONFIG_BORDER_AGENT_ENABLE
+
+template <> otError NcpBase::HandlePropertyGet<SPINEL_PROP_BORDER_AGENT_MESHCOP_SERVICE_STATE>(void)
+{
+    otError                            error = OT_ERROR_NONE;
+    otBorderAgentMeshCoPServiceTxtData txtData;
+
+    SuccessOrExit(error = otBorderAgentGetMeshCoPServiceTxtData(mInstance, &txtData));
+    SuccessOrExit(error = mEncoder.WriteBool(otBorderAgentIsActive(mInstance)));
+    SuccessOrExit(error = mEncoder.WriteUint16(otBorderAgentGetUdpPort(mInstance)));
+    SuccessOrExit(error = mEncoder.WriteData(txtData.mData, txtData.mLength));
+
+exit:
+    return error;
+}
+
+#endif // OPENTHREAD_CONFIG_BORDER_AGENT_ENABLE
+
 } // namespace Ncp
 } // namespace ot