[mac] enable Beacon Payload in outgoing beacons (#7767)

This commit enables beacon payloads on outgoing beacons to prevent
backward compatibility issues with existing devices in the market.

script/check-simulation-build-autotools

@@ -90,6 +90,7 @@ build_all_features()
         "-DOPENTHREAD_CONFIG_TMF_NETWORK_DIAG_MTD_ENABLE=1"
         "-DOPENTHREAD_CONFIG_UDP_FORWARD_ENABLE=1"
         "-DOPENTHREAD_CONFIG_MAC_BEACON_PAYLOAD_PARSING_ENABLE=1"
+        "-DOPENTHREAD_CONFIG_MAC_OUTGOING_BEACON_PAYLOAD_ENABLE=1"
     )
 
     local options_1_2=(

src/core/config/mac.h

@@ -510,4 +510,15 @@
 #define OPENTHREAD_CONFIG_MAC_BEACON_PAYLOAD_PARSING_ENABLE 0
 #endif
 
+/**
+ * @def OPENTHREAD_CONFIG_MAC_OUTGOING_BEACON_PAYLOAD_ENABLE
+ *
+ * This setting configures if the beacon payload needs to be enabled in outgoing beacon frames. This is optional and is
+ * disabled by default because Thread 1.2.1 has removed support for beacon payloads.
+ *
+ */
+#ifndef OPENTHREAD_CONFIG_MAC_OUTGOING_BEACON_PAYLOAD_ENABLE
+#define OPENTHREAD_CONFIG_MAC_OUTGOING_BEACON_PAYLOAD_ENABLE 0
+#endif
+
 #endif // CONFIG_MAC_H_

src/core/mac/mac.cpp

@@ -737,6 +737,10 @@ TxFrame *Mac::PrepareBeacon(void)
     TxFrame *frame;
     uint16_t fcf;
     Beacon * beacon = nullptr;
+#if OPENTHREAD_CONFIG_MAC_OUTGOING_BEACON_PAYLOAD_ENABLE
+    uint8_t        beaconLength;
+    BeaconPayload *beaconPayload = nullptr;
+#endif
 
 #if OPENTHREAD_CONFIG_MULTI_RADIO
     OT_ASSERT(!mTxBeaconRadioLinks.IsEmpty());
@@ -754,6 +758,30 @@ TxFrame *Mac::PrepareBeacon(void)
     beacon = reinterpret_cast<Beacon *>(frame->GetPayload());
     beacon->Init();
 
+#if OPENTHREAD_CONFIG_MAC_OUTGOING_BEACON_PAYLOAD_ENABLE
+    beaconLength = sizeof(*beacon);
+
+    beaconPayload = reinterpret_cast<BeaconPayload *>(beacon->GetPayload());
+
+    beaconPayload->Init();
+
+    if (IsJoinable())
+    {
+        beaconPayload->SetJoiningPermitted();
+    }
+    else
+    {
+        beaconPayload->ClearJoiningPermitted();
+    }
+
+    beaconPayload->SetNetworkName(Get<MeshCoP::NetworkNameManager>().GetNetworkName().GetAsData());
+    beaconPayload->SetExtendedPanId(Get<MeshCoP::ExtendedPanIdManager>().GetExtPanId());
+
+    beaconLength += sizeof(*beaconPayload);
+
+    frame->SetPayloadLength(beaconLength);
+#endif
+
     LogBeacon("Sending");
 
     return frame;

src/core/mac/mac_frame.hpp

@@ -43,6 +43,7 @@
 #include "common/const_cast.hpp"
 #include "common/encoding.hpp"
 #include "mac/mac_types.hpp"
+#include "meshcop/network_name.hpp"
 
 namespace ot {
 namespace Mac {
@@ -1482,7 +1483,6 @@ private:
     uint8_t  mPendingAddressSpec;
 } OT_TOOL_PACKED_END;
 
-#if OPENTHREAD_CONFIG_MAC_BEACON_PAYLOAD_PARSING_ENABLE
 /**
  * This class implements IEEE 802.15.4 Beacon Payload generation and parsing.
  *
@@ -1491,16 +1491,22 @@ OT_TOOL_PACKED_BEGIN
 class BeaconPayload
 {
 public:
-    static constexpr uint8_t kProtocolId    = 3;      ///< Thread Protocol ID.
-    static constexpr uint8_t kVersionOffset = 4;      ///< Version field bit offset.
-    static constexpr uint8_t kNativeFlag    = 1 << 3; ///< Native Commissioner flag.
-    static constexpr uint8_t kJoiningFlag   = 1 << 0; ///< Joining Permitted flag.
+    static constexpr uint8_t kProtocolId      = 3;                     ///< Thread Protocol ID.
+    static constexpr uint8_t kProtocolVersion = 2;                     ///< Thread Protocol version.
+    static constexpr uint8_t kVersionOffset   = 4;                     ///< Version field bit offset.
+    static constexpr uint8_t kVersionMask     = 0xf << kVersionOffset; ///< Version field mask.
+    static constexpr uint8_t kNativeFlag      = 1 << 3;                ///< Native Commissioner flag.
+    static constexpr uint8_t kJoiningFlag     = 1 << 0;                ///< Joining Permitted flag.
 
     /**
-     * This constant specified the maximum number of chars in Network Name (excludes null char).
+     * This method initializes the Beacon Payload.
      *
      */
-    static constexpr uint8_t kMaxSize = OT_NETWORK_NAME_MAX_SIZE;
+    void Init(void)
+    {
+        mProtocolId = kProtocolId;
+        mFlags      = kProtocolVersion << kVersionOffset;
+    }
 
     /**
      * This method indicates whether or not the beacon appears to be a valid Thread Beacon Payload.
@@ -1536,6 +1542,18 @@ public:
      */
     bool IsNative(void) const { return (mFlags & kNativeFlag) != 0; }
 
+    /**
+     * This method clears the Native Commissioner flag.
+     *
+     */
+    void ClearNative(void) { mFlags &= ~kNativeFlag; }
+
+    /**
+     * This method sets the Native Commissioner flag.
+     *
+     */
+    void SetNative(void) { mFlags |= kNativeFlag; }
+
     /**
      * This method indicates whether or not the Joining Permitted flag is set.
      *
@@ -1545,13 +1563,41 @@ public:
      */
     bool IsJoiningPermitted(void) const { return (mFlags & kJoiningFlag) != 0; }
 
+    /**
+     * This method clears the Joining Permitted flag.
+     *
+     */
+    void ClearJoiningPermitted(void) { mFlags &= ~kJoiningFlag; }
+
+    /**
+     * This method sets the Joining Permitted flag.
+     *
+     */
+    void SetJoiningPermitted(void)
+    {
+        mFlags |= kJoiningFlag;
+
+#if OPENTHREAD_CONFIG_MAC_JOIN_BEACON_VERSION != 2 // check against kProtocolVersion
+        mFlags &= ~kVersionMask;
+        mFlags |= OPENTHREAD_CONFIG_MAC_JOIN_BEACON_VERSION << kVersionOffset;
+#endif
+    }
+
     /**
      * This method gets the Network Name field.
      *
      * @returns The Network Name field as `NameData`.
      *
      */
-    const char *GetNetworkName(void) const { return mNetworkName; }
+    MeshCoP::NameData GetNetworkName(void) const { return MeshCoP::NameData(mNetworkName, sizeof(mNetworkName)); }
+
+    /**
+     * This method sets the Network Name field.
+     *
+     * @param[in]  aNameData  The Network Name (as a `NameData`).
+     *
+     */
+    void SetNetworkName(const MeshCoP::NameData &aNameData) { aNameData.CopyTo(mNetworkName, sizeof(mNetworkName)); }
 
     /**
      * This method returns the Extended PAN ID field.
@@ -1561,13 +1607,20 @@ public:
      */
     const otExtendedPanId &GetExtendedPanId(void) const { return mExtendedPanId; }
 
+    /**
+     * This method sets the Extended PAN ID field.
+     *
+     * @param[in]  aExtPanId  An Extended PAN ID.
+     *
+     */
+    void SetExtendedPanId(const otExtendedPanId &aExtPanId) { mExtendedPanId = aExtPanId; }
+
 private:
     uint8_t         mProtocolId;
     uint8_t         mFlags;
-    char            mNetworkName[kMaxSize];
+    char            mNetworkName[MeshCoP::NetworkName::kMaxSize];
     otExtendedPanId mExtendedPanId;
 } OT_TOOL_PACKED_END;
-#endif // OPENTHREAD_CONFIG_MAC_BEACON_PAYLOAD_PARSING_ENABLE
 
 /**
  * This class implements CSL IE data structure.