feat: add new SRx_OPTIONS bitmask parameter with a mavlink2-signing bit

Author: ben-sembira-1

libraries/GCS_MAVLink/GCS.h

@@ -163,6 +163,12 @@ class GCS_MAVLINK_InProgress
     static uint32_t last_check_ms;
 };
 
+enum class SROption : int16_t
+{
+    None = 0,
+    MAVLINK2_SIGNING = (1U << 0),
+};
+
 ///
 /// @class	GCS_MAVLINK
 /// @brief	MAVLink transport control class
@@ -512,6 +518,11 @@ class GCS_MAVLINK
     virtual bool persist_streamrates() const { return false; }
     void handle_request_data_stream(const mavlink_message_t &msg);
 
+    AP_Int16 options;
+    bool option_enabled(SROption option) const {
+        return options & static_cast<int16_t>(option);
+    }
+
     virtual void handle_command_ack(const mavlink_message_t &msg);
     void handle_set_mode(const mavlink_message_t &msg);
     void handle_command_int(const mavlink_message_t &msg);

libraries/GCS_MAVLink/GCS_MAVLink_Parameters.cpp

@@ -22,6 +22,9 @@ const struct AP_Param::GroupInfo *GCS::_chan_var_info[MAVLINK_COMM_NUM_BUFFERS];
 
 // tradition has different vehicles use different default stream rates.  This may not be the case forever, but for now we maintain this behaviour:
 
+// Unified signing options across all vehicles
+#define STANDARD_DEFAULT_STREAM_RATE_OPTIONS (SROption::MAVLINK2_SIGNING)
+
 #ifndef AP_MAV_DEFAULT_STREAM_RATE_RAW_SENS
 #if APM_BUILD_TYPE(APM_BUILD_ArduSub)
 #define AP_MAV_DEFAULT_STREAM_RATE_RAW_SENS 2
@@ -34,6 +37,7 @@ const struct AP_Param::GroupInfo *GCS::_chan_var_info[MAVLINK_COMM_NUM_BUFFERS];
 #define AP_MAV_DEFAULT_STREAM_RATE_EXTRA3 3
 #define AP_MAV_DEFAULT_STREAM_RATE_PARAMS 0
 #define AP_MAV_DEFAULT_STREAM_RATE_ADSB 0
+#define AP_MAV_DEFAULT_STREAM_RATE_OPTIONS STANDARD_DEFAULT_STREAM_RATE_OPTIONS
 #elif APM_BUILD_TYPE(APM_BUILD_AntennaTracker) || APM_BUILD_TYPE(APM_BUILD_Rover)
 #define AP_MAV_DEFAULT_STREAM_RATE_RAW_SENS 1
 #define AP_MAV_DEFAULT_STREAM_RATE_EXT_STAT 1
@@ -45,6 +49,7 @@ const struct AP_Param::GroupInfo *GCS::_chan_var_info[MAVLINK_COMM_NUM_BUFFERS];
 #define AP_MAV_DEFAULT_STREAM_RATE_EXTRA3 1
 #define AP_MAV_DEFAULT_STREAM_RATE_PARAMS 10
 #define AP_MAV_DEFAULT_STREAM_RATE_ADSB 0
+#define AP_MAV_DEFAULT_STREAM_RATE_OPTIONS STANDARD_DEFAULT_STREAM_RATE_OPTIONS
 #elif APM_BUILD_TYPE(APM_BUILD_ArduPlane)
 #define AP_MAV_DEFAULT_STREAM_RATE_RAW_SENS 1
 #define AP_MAV_DEFAULT_STREAM_RATE_EXT_STAT 1
@@ -56,6 +61,7 @@ const struct AP_Param::GroupInfo *GCS::_chan_var_info[MAVLINK_COMM_NUM_BUFFERS];
 #define AP_MAV_DEFAULT_STREAM_RATE_EXTRA3 1
 #define AP_MAV_DEFAULT_STREAM_RATE_PARAMS 10
 #define AP_MAV_DEFAULT_STREAM_RATE_ADSB 5
+#define AP_MAV_DEFAULT_STREAM_RATE_OPTIONS STANDARD_DEFAULT_STREAM_RATE_OPTIONS
 #elif APM_BUILD_COPTER_OR_HELI || APM_BUILD_TYPE(APM_BUILD_Blimp) || APM_BUILD_TYPE(APM_BUILD_Replay) || APM_BUILD_TYPE(APM_BUILD_AP_Periph)
 #define AP_MAV_DEFAULT_STREAM_RATE_RAW_SENS 0
 #define AP_MAV_DEFAULT_STREAM_RATE_EXT_STAT 0
@@ -67,6 +73,7 @@ const struct AP_Param::GroupInfo *GCS::_chan_var_info[MAVLINK_COMM_NUM_BUFFERS];
 #define AP_MAV_DEFAULT_STREAM_RATE_EXTRA3 0
 #define AP_MAV_DEFAULT_STREAM_RATE_PARAMS 0
 #define AP_MAV_DEFAULT_STREAM_RATE_ADSB 0
+#define AP_MAV_DEFAULT_STREAM_RATE_OPTIONS STANDARD_DEFAULT_STREAM_RATE_OPTIONS
 #elif APM_BUILD_TYPE(APM_BUILD_UNKNOWN)
 #define AP_MAV_DEFAULT_STREAM_RATE_RAW_SENS 0
 #define AP_MAV_DEFAULT_STREAM_RATE_EXT_STAT 0
@@ -78,6 +85,7 @@ const struct AP_Param::GroupInfo *GCS::_chan_var_info[MAVLINK_COMM_NUM_BUFFERS];
 #define AP_MAV_DEFAULT_STREAM_RATE_EXTRA3 0
 #define AP_MAV_DEFAULT_STREAM_RATE_PARAMS 0
 #define AP_MAV_DEFAULT_STREAM_RATE_ADSB 0
+#define AP_MAV_DEFAULT_STREAM_RATE_OPTIONS STANDARD_DEFAULT_STREAM_RATE_OPTIONS
 #else
 #error Need to set streamrates
 #endif  // APM_BUILD_TYPE
@@ -202,6 +210,18 @@ const AP_Param::GroupInfo GCS_MAVLINK::var_info[] = {
     // @RebootRequired: True
     // @User: Advanced
     AP_GROUPINFO("_ADSB",   10, GCS_MAVLINK, streamRates[GCS_MAVLINK::STREAM_ADSB], DRATE(GCS_MAVLINK::STREAM_ADSB)),
+
+    // ------------
+    // IMPORTANT: Add new stream rates *before* the _OPTIONS parameter.
+    // ------------
+
+    // @Param: _OPTIONS
+    // @DisplayName: Bitmask for configuring this telemetry channel
+    // @Description: Bitmask for configuring this telemetry channel. For having effect on all channels, set the relevant mask in all SRx_OPTIONS parameters. Keep in mind that part of the flags may require a reboot to take action.
+    // @RebootRequired: True
+    // @User: Standard
+    // @Bitmask: 0:Enable MavLink2 signing (Reboot required)
+    AP_GROUPINFO("_OPTIONS",   11, GCS_MAVLINK, options, float(AP_MAV_DEFAULT_STREAM_RATE_OPTIONS)),
     AP_GROUPEND
 };
 #undef DRATE

libraries/GCS_MAVLink/GCS_Signing.cpp

@@ -133,7 +133,8 @@ static bool accept_unsigned_callback(const mavlink_status_t *status, uint32_t ms
 void GCS_MAVLINK::load_signing_key(void)
 {
     struct SigningKey key;
-    if (!signing_key_load(key)) {
+    if (!option_enabled(SROption::MAVLINK2_SIGNING) || !signing_key_load(key))
+    {
         return;
     }
     memcpy(signing.secret_key, key.secret_key, 32);