don't let phones send down fatally invalid RadioConfig records

and if a phone did in the past, fixup the garbage we saved in flash

src/MeshRadio.cpp

@@ -10,10 +10,6 @@
 #include <pb_decode.h>
 #include <pb_encode.h>
 
-/// 16 bytes of random PSK for our _public_ default channel that all devices power up on
-static const uint8_t defaultpsk[] = {0xd4, 0xf1, 0xbb, 0x3a, 0x20, 0x29, 0x07, 0x59,
-                                     0xf0, 0xbc, 0xff, 0xab, 0xcf, 0x4e, 0x69, 0xbf};
-
 /**
  * ## LoRaWAN for North America
 
@@ -32,14 +28,6 @@ MeshRadio::MeshRadio(MemoryPool<MeshPacket> &_pool, PointerQueue<MeshPacket> &_r
 {
     myNodeInfo.num_channels = NUM_CHANNELS;
 
-    // radioConfig.modem_config = RadioConfig_ModemConfig_Bw125Cr45Sf128;  // medium range and fast
-    // channelSettings.modem_config = ChannelSettings_ModemConfig_Bw500Cr45Sf128;  // short range and fast, but wide bandwidth so
-    // incompatible radios can talk together
-    channelSettings.modem_config = ChannelSettings_ModemConfig_Bw125Cr48Sf4096; // slow and long range
-
-    channelSettings.tx_power = 23;
-    memcpy(&channelSettings.psk, &defaultpsk, sizeof(channelSettings.psk));
-    strcpy(channelSettings.name, "Default");
     // Can't print strings this early - serial not setup yet
     // DEBUG_MSG("Set meshradio defaults name=%s\n", channelSettings.name);
 }
@@ -122,7 +110,7 @@ void MeshRadio::reloadConfig()
     // FIXME - can we do this?  It seems to be in the Heltec board.
     rf95.setTxPower(channelSettings.tx_power, false);
 
-    DEBUG_MSG("Set radio: name=%s. config=%u, ch=%d, txpower=%d\n", channelSettings.name, channelSettings.modem_config,
+    DEBUG_MSG("Set radio: name=%s, config=%u, ch=%d, txpower=%d\n", channelSettings.name, channelSettings.modem_config,
               channel_num, channelSettings.tx_power);
 
     // Done with init tell radio to start receiving

src/MeshService.cpp

@@ -217,6 +217,7 @@ void MeshService::loop()
 void MeshService::reloadConfig()
 {
     // If we can successfully set this radio to these settings, save them to disk
+    nodeDB.resetRadioConfig(); // Don't let the phone send us fatally bad settings
     radio.reloadConfig();
     nodeDB.saveToDisk();
 }

src/NodeDB.cpp

@@ -44,9 +44,37 @@ static uint8_t ourMacAddr[6];
 
 NodeDB::NodeDB() : nodes(devicestate.node_db), numNodes(&devicestate.node_db_count) {}
 
+void NodeDB::resetRadioConfig()
+{
+    /// 16 bytes of random PSK for our _public_ default channel that all devices power up on
+    static const uint8_t defaultpsk[] = {0xd4, 0xf1, 0xbb, 0x3a, 0x20, 0x29, 0x07, 0x59,
+                                         0xf0, 0xbc, 0xff, 0xab, 0xcf, 0x4e, 0x69, 0xbf};
+
+    if (radioConfig.preferences.sds_secs == 0) {
+        DEBUG_MSG("RadioConfig reset!\n");
+        radioConfig.preferences.send_owner_interval = 4; // per sw-design.md
+        radioConfig.preferences.position_broadcast_secs = 15 * 60;
+        radioConfig.preferences.wait_bluetooth_secs = 120;
+        radioConfig.preferences.screen_on_secs = 30;
+        radioConfig.preferences.mesh_sds_timeout_secs = 2 * 60 * 60;
+        radioConfig.preferences.phone_sds_timeout_sec = 2 * 60 * 60;
+        radioConfig.preferences.sds_secs = 365 * 24 * 60 * 60; // one year
+        radioConfig.preferences.ls_secs = 60 * 60;
+        radioConfig.preferences.phone_timeout_secs = 15 * 60;
+
+        // radioConfig.modem_config = RadioConfig_ModemConfig_Bw125Cr45Sf128;  // medium range and fast
+        // channelSettings.modem_config = ChannelSettings_ModemConfig_Bw500Cr45Sf128;  // short range and fast, but wide bandwidth
+        // so incompatible radios can talk together
+        channelSettings.modem_config = ChannelSettings_ModemConfig_Bw125Cr48Sf4096; // slow and long range
+
+        channelSettings.tx_power = 23;
+        memcpy(&channelSettings.psk, &defaultpsk, sizeof(channelSettings.psk));
+        strcpy(channelSettings.name, "Default");
+    }
+}
+
 void NodeDB::init()
 {
-
     // init our devicestate with valid flags so protobuf writing/reading will work
     devicestate.has_my_node = true;
     devicestate.has_radio = true;
@@ -57,15 +85,7 @@ void NodeDB::init()
     devicestate.node_db_count = 0;
     devicestate.receive_queue_count = 0;
 
-    radioConfig.preferences.send_owner_interval = 4; // per sw-design.md
-    radioConfig.preferences.position_broadcast_secs = 15 * 60;
-    radioConfig.preferences.wait_bluetooth_secs = 120;
-    radioConfig.preferences.screen_on_secs = 30;
-    radioConfig.preferences.mesh_sds_timeout_secs = 2 * 60 * 60;
-    radioConfig.preferences.phone_sds_timeout_sec = 2 * 60 * 60;
-    radioConfig.preferences.sds_secs = 365 * 24 * 60 * 60; // one year
-    radioConfig.preferences.ls_secs = 60 * 60;
-    radioConfig.preferences.phone_timeout_secs = 15 * 60;
+    resetRadioConfig();
 
     // default to no GPS, until one has been found by probing
     myNodeInfo.has_gps = false;
@@ -102,6 +122,7 @@ void NodeDB::init()
 
     // saveToDisk();
     loadFromDisk();
+    resetRadioConfig(); // If bogus settings got saved, then fix them
 
     DEBUG_MSG("NODENUM=0x%x, dbsize=%d\n", myNodeInfo.my_node_num, *numNodes);
 }

src/NodeDB.h

@@ -43,6 +43,9 @@ class NodeDB
     /// write to flash
     void saveToDisk();
 
+    // Reinit radio config if needed, because sometimes a buggy android app might send us bogus settings
+    void resetRadioConfig();
+
     /// given a subpacket sniffed from the network, update our DB state
     /// we updateGUI and updateGUIforNode if we think our this change is big enough for a redraw
     void updateFrom(const MeshPacket &p);