MQTT WIP

bin/mqtt-listen.sh

@@ -1 +1 @@
-mosquitto_sub -h test.mosquitto.org -v -t mstat/\# -t mesh/\#
+mosquitto_sub -h test.mosquitto.org -v -t mesh/\#

bin/mqtt-send-status.sh

@@ -1 +1 @@
-mosquitto_pub -h test.mosquitto.org -t mstat/FakeNode -m online -d
+mosquitto_pub -h test.mosquitto.org -t mesh/stat/FakeNode -m online -d

docs/software/TODO.md

@@ -55,18 +55,22 @@ You probably don't care about this section - skip to the next one.
 
 * DONE have sim provide a fake wifi connection status saying connected
 * DONE don't start MQTT if we don't have wifi connected
+* have plugin send uplinks from mesh
+* have plugin send downlinks to mesh
+* don't decrypt messages before uplinking them to MQTT (move out of plugin)
 * mqtt.meshtastic.org should have VERY basic auth at launch (to prevent abuse)
 * make a GlobalChat channel as an initial test (with a well known AES128 key), figure out how globally unique IDs work
 * Give place in android app for users to select which channel they are sending on (and which channels they are watching)
 * attempt reconnect to server if internet connectivity changes
 * don't bother contacting server if we don't have any uplink/downlink channels
-* test on ESP32
+* DONE test on ESP32
 * no need for python gateway to web initially: because both the simulator and ESP32 can talk wifi directly
 * if simmesh_name is set in preferences, create the MQTTSimInterface using that as the global channel_id
 * figure out how to use MQTT for simulator mesh network, use a special simmesh_name global channel_id? (because this would allow all nodes in simnet_xxx to subscribe only to those packets)
-* do initial development inside of portduino
-* do as much possible on the device side (so we can eventually just have ESP32 talk directly to server)
-* add mqtt_server to radio prefs
+* figure out legality of hosting public mqtt servers with chat msgs
+* DONE do initial development inside of portduino
+* DONE do as much possible on the device side (so we can eventually just have ESP32 talk directly to server)
+* DONE add mqtt_server to radio prefs
 * eventually add a MQTTPacket on the ToRadio & FromRadio links
 * LATER: an android gateway would be useful
 

docs/software/mqtt.md

@@ -70,19 +70,19 @@ Any gateway-device will contact the MQTT broker.
 
 ### Topics
 
-* The "/mesh/crypt/CHANNELID/NODEID/PORTID" [topic](https://www.hivemq.com/blog/mqtt-essentials-part-5-mqtt-topics-best-practices/) will be used for messages sent from/to a mesh.
+* The "/mesh/crypt/CHANNELID/NODEID" [topic](https://www.hivemq.com/blog/mqtt-essentials-part-5-mqtt-topics-best-practices/) will be used for (encrypted) messages sent from/to a mesh.
 
 Gateway nodes will foward any MeshPacket from a local mesh channel with uplink_enabled.  The packet (encapsulated in a ServiceEnvelope) will remain encrypted with the key for the specified channel.  
 
 For any channels in the gateway node with downlink_enabled, the gateway node will forward packets from MQTT to the local mesh.  It will do this by subscribing to mesh/crypt/CHANNELID/# and forwarding relevant packets.
 
-If the channelid 'well known'/public it could be decrypted by a web service (if the web service was provided with the associated channel key), in which case it will be decrypted by a web service and appear at "mesh/clear/CHANNELID/NODEID/PORTID". Note: This is not in the initial deliverable. 
+* If the channelid 'well known'/public it could be decrypted by a web service (if the web service was provided with the associated channel key), in which case it will be decrypted by a web service and appear at "mesh/clear/CHANNELID/NODEID/PORTID". Note: This is not in the initial deliverable. 
 
 FIXME, consider how text message global mirroring could scale (or not)
 FIXME, possibly don't global mirror text messages - instead rely on matrix/riot? 
 FIXME, consider possible attacks by griefers and how they can be prvented
 
-* The "/mstat/NODEID" topic contains a simple string showing connection status of nodes.  We rely on the MQTT feature for automatically publishing special failrue messages to this topic when the device disconnects.
+* The "/mesh/stat/NODEID" topic contains a simple string showing connection status of nodes.  We rely on the MQTT feature for automatically publishing special failrue messages to this topic when the device disconnects.
 
 #### Service Envelope
 

src/mqtt/MQTT.cpp

@@ -1,12 +1,13 @@
 #include "MQTT.h"
+#include "MQTTPlugin.h"
 #include "NodeDB.h"
+#include "mesh/generated/mqtt.pb.h"
 #include <WiFi.h>
 #include <assert.h>
 
 MQTT *mqtt;
 
-String statusTopic = "mstat/";
-String packetTopic = "mesh/";
+String statusTopic = "mesh/stat/";
 
 void mqttCallback(char *topic, byte *payload, unsigned int length)
 {
@@ -23,8 +24,10 @@ void mqttInit()
         DEBUG_MSG("MQTT disabled...\n");
     else if (!WiFi.isConnected())
         DEBUG_MSG("WiFi is not connected, can not start MQTT\n");
-    else
+    else {
         new MQTT();
+        new MQTTPlugin();
+    }
 }
 
 MQTT::MQTT() : pubSub(mqttClient)
@@ -59,18 +62,35 @@ MQTT::MQTT() : pubSub(mqttClient)
     }
 }
 
-void MQTT::publish(const MeshPacket *mp)
+void MQTT::publish(const MeshPacket &mp)
 {
-    // DEBUG_MSG("publish %s = %s\n", suffix.c_str(), payload.c_str());
+    // don't bother sending if not connected...
+    if (pubSub.connected()) {
+        // FIXME - check uplink enabled
 
-    // pubSub.publish(getTopic(suffix), payload.c_str(), retained);
+        const char *channelId = "fixmechan";
+
+        ServiceEnvelope env = ServiceEnvelope_init_default;
+        env.channel_id = (char *)channelId;
+        env.gateway_id = owner.id;
+        env.packet = (MeshPacket *)&mp;
+
+        // FIXME - this size calculation is super sloppy, but it will go away once we dynamically alloc meshpackets
+        static uint8_t bytes[MeshPacket_size + 64];
+        size_t numBytes = pb_encode_to_bytes(bytes, sizeof(bytes), ServiceEnvelope_fields, &env);
+
+        const char *topic = getCryptTopic(channelId);
+        DEBUG_MSG("publish %s, %u bytes\n", topic, numBytes);
+
+        pubSub.publish(topic, bytes, numBytes, false);
+    }
 }
 
-const char *MQTT::getTopic(String suffix, const char *direction)
+const char *MQTT::getCryptTopic(const char *channelId)
 {
     static char buf[128];
 
     // "mesh/crypt/CHANNELID/NODEID/PORTID"
-    snprintf(buf, sizeof(buf), "mesh/%s/%s/%s", direction, owner.id, suffix.c_str());
+    snprintf(buf, sizeof(buf), "mesh/crypt/%s/%s", channelId, owner.id);
     return buf;
 }

src/mqtt/MQTT.h

@@ -23,10 +23,10 @@ class MQTT
     /**
      * Publish a packet on the glboal MQTT server.
      */
-    void publish(const MeshPacket *mp);
+    void publish(const MeshPacket &mp);
 
   private:
-    const char *getTopic(String suffix, const char *direction = "dev");
+    const char *getCryptTopic(const char *channelId);
 };
 
 void mqttInit();

src/mqtt/MQTTPlugin.cpp

@@ -0,0 +1,18 @@
+#include "MQTTPlugin.h"
+#include "MQTT.h"
+#include "MeshService.h"
+#include "NodeDB.h"
+#include "Router.h"
+#include "configuration.h"
+#include "main.h"
+
+MQTTPlugin::MQTTPlugin() : MeshPlugin("mqtt")
+{
+    isPromiscuous = true; // We always want to update our nodedb, even if we are sniffing on others
+}
+
+bool MQTTPlugin::handleReceived(const MeshPacket &mp)
+{
+    mqtt->publish(mp);
+    return false; // never claim handled
+}

src/mqtt/MQTTPlugin.h

@@ -0,0 +1,17 @@
+#pragma once
+#include "MeshPlugin.h"
+
+/**
+ * NodeInfo plugin for sending/receiving NodeInfos into the mesh
+ */
+class MQTTPlugin : public MeshPlugin
+{
+  public:
+    MQTTPlugin();
+
+  protected:
+    /** We sniff all packets */
+    virtual bool handleReceived(const MeshPacket &mp);
+
+    virtual bool wantPacket(const MeshPacket *p) { return true; }
+};