Improve configuration, refactoring

include/controller.h

@@ -7,21 +7,50 @@
 #include "fresh.h"
 #include <ESPAsyncWebServer.h>
 
+struct WifiConfiguration {
+
+    // The WiFi network to connect to
+    const char* ssid;
+
+    // The WiFi password to connect to the above network
+    const char* password;
+
+    // The name of the device on the network
+    const char* networkName;
+
+    // The interval to reconnect to WiFi if the connection is broken
+    uint32_t reconnectInterval;
+};
+
+struct KeyConfiguration {
+
+    const uint8_t* remoteKey;
+
+    const uint8_t* localKey;
+};
+
 class SesameController: public ServerConnectionCallbacks {
 
 public:
-    SesameController(ServerConnection* server, ServoController* servo, AsyncWebServer* local, TimeCheck* timeCheck, uint8_t remoteDeviceCount);
+    SesameController(uint16_t localWebServerPort, uint8_t remoteDeviceCount);
 
-    void configure();
+    void configure(ServoConfiguration servoConfig, ServerConfiguration serverConfig, TimeConfiguration timeConfig, WifiConfiguration wifiConfig, KeyConfiguration keyConfig);
+
+    void loop(uint32_t millis);
 
 private:
 
-    ServerConnection* server;
+    ServerConnection server;
-    ServoController* servo;
+    ServoController servo;
-    AsyncWebServer* local;
+    AsyncWebServer localWebServer;
-    TimeCheck* timeCheck;
+    TimeCheck timeCheck;
     Storage storage;
 
+    WifiConfiguration wifiConfig;
+    KeyConfiguration keyConfig;
+
+    bool isReconnecting = false;
+
     // The buffer to hold a received message while it is read
     uint8_t receivedMessageBuffer[AUTHENTICATED_MESSAGE_SIZE];
 
@@ -31,6 +60,9 @@ private:
     AuthenticatedMessage* responseMessage;
     uint16_t responseSize = 0;
 
+    void ensureWiFiConnection(uint32_t time);
+    void ensureWebSocketConnection();
+
     void handleLocalMessage(AsyncWebServerRequest *request);
     // Based on https://stackoverflow.com/a/23898449/266720
     bool convertHexMessageToBinary(const char* str);

include/example_config.h

@@ -52,11 +52,7 @@ constexpr uint32_t wifiReconnectInterval = 10000;
 /* Local server */
 
 // The port for the local server to directly receive messages over WiFi
-constexpr uint16_t localPort = 80;
+constexpr uint16_t localWebServerPort = 80;
-
-// The url parameter to send the message to the local server
-constexpr char messageUrlParameter[] = "m";
-
 
 /* Server */ 
 

include/fresh.h

@@ -1,7 +1,34 @@
 #pragma once
 
 #include <stdint.h>
-#include "config.h"
+
+struct TimeConfiguration {
+
+    /**
+     * @brief The timezone offset in seconds
+     */
+    int32_t offsetToGMT;
+
+    /**
+     * @brief The daylight savings offset in seconds
+     */
+    int32_t offsetDaylightSavings;
+
+    /**
+     * @brief The url of the NTP server
+     */
+    const char* ntpServerUrl;
+
+    /**
+     * @brief The allowed discrepancy between the time of a received message
+     * and the device time (in seconds)
+     * 
+     * A stricter (lower) value better prevents against replay attacks,
+     * but may lead to issues when dealing with slow networks and other
+     * routing delays.
+     */
+    uint32_t allowedTimeOffset;
+};
 
 class TimeCheck {
 
@@ -9,26 +36,18 @@ public:
 
     /**
      * @brief Create a time checker instance
-     * 
-     * Specify the allowed discrepancy between the time of a received message
-     * and the device time (in seconds).
-     * 
-     * A stricter (lower) value better prevents against replay attacks,
-     * but may lead to issues when dealing with slow networks and other
-     * routing delays.
-     * 
-     * @param offset The allowed time discrepancy in both directions (seconds)
      */
-    TimeCheck(uint32_t allowedTimeOffset = 60);
+    TimeCheck();
 
     /**
-     * @brief Configure an NTP server to get the current time
+     * @brief Set the configuration
-     * 
-     * @param offsetToGMT The timezone offset in seconds
-     * @param offsetDaylightSavings The daylight savings offset in seconds
-     * @param serverUrl The url of the NTP server
      */
-    void configureNTP(int32_t offsetToGMT, int32_t offsetDaylightSavings, const char* serverUrl);
+    void configure(TimeConfiguration configuration);
+
+    /**
+     * @brief Configure the NTP server to get the current time
+     */
+    void startNTP();
 
     /**
      * @brief Print the current time to the serial output
@@ -42,20 +61,6 @@ public:
      */
     uint32_t getEpochTime();
 
-    /**
-     * @brief The allowed time discrepancy (in seconds)
-     * 
-     * Specifies the allowed discrepancy between the time of a received message
-     * and the device time (in seconds).
-     * 
-     * A stricter (lower) value better prevents against replay attacks,
-     * but may lead to issues when dealing with slow networks and other
-     * routing delays.
-     * 
-     * @param offset The offset in both directions (seconds)
-     */
-    void setMessageTimeAllowedOffset(uint32_t offset);
-
     /**
      * @brief Check wether the time of a message is within the allowed bounds regarding freshness.
      * 
@@ -71,13 +76,5 @@ public:
 
 private:
 
-    /**
+    TimeConfiguration config;
-     * @brief The allowed discrepancy between the time of a received message
-     * and the device time (in seconds)
-     * 
-     * A stricter (lower) value better prevents against replay attacks,
-     * but may lead to issues when dealing with slow networks and other
-     * routing delays.
-     */
-    uint32_t allowedOffset;
 };

include/server.h

@@ -6,6 +6,32 @@
 #include <WiFiClientSecure.h>
 #include <WebSocketsClient.h>
 
+struct ServerConfiguration {
+
+    /**
+     * @brief The url of the remote server to connect to
+     */
+    const char* url; 
+    
+    /**
+     * @brief The server port
+     */
+    int port;
+
+    /**
+     * @brief The path on the server
+     */
+    const char* path;
+
+    /**
+     * @brief The authentication key for the server
+     */
+    const char* key;
+    
+    uint32_t reconnectTime;
+
+};
+
 class ServerConnectionCallbacks {
 
 public:
@@ -18,18 +44,18 @@ class ServerConnection {
 
 public:
 
-    ServerConnection(const char* url, int port, const char* path);
+    ServerConnection();
-
-    void connect(const char* key, uint32_t reconnectTime = 5000);
-
-    void loop();
 
     /**
-     * @brief Set the handler
+     * @brief Set the configuration and the callback handler
      * 
      * @param callback The handler to handle messages and errors
      */
-    void setCallbackHandler(ServerConnectionCallbacks* callbacks);
+    void configure(ServerConfiguration configuration, ServerConnectionCallbacks* callbacks);
+
+    void connect();
+
+    void loop();
 
     /**
      * @brief Send a response message over the socket
@@ -45,13 +71,7 @@ public:
 
 private:
 
-    const char* url;
+    ServerConfiguration configuration;
-
-    int port;
-
-    const char* path;
-
-    const char* key = NULL;
 
     // Indicator that the socket is connected.
     bool socketIsConnected = false;

include/servo.h

@@ -3,7 +3,7 @@
 #include <stdint.h>
 #include <ESP32Servo.h> // To control the servo
 
-typedef struct ServoConfiguration {
+struct ServoConfiguration {
     /**
      * @brief The timer to use for the servo control
      * number 0-3 indicating which timer to allocate in this library
@@ -34,6 +34,7 @@ typedef struct ServoConfiguration {
      * @brief The servo value (in µs) that specifies the 'released' state
      */
     int releasedValue;
+
 };
 
 /**
@@ -70,7 +71,7 @@ public:
      * There is no required interval to call this function, but the accuracy of
      * the opening interval is dependent on the calling frequency.
      */
-    void loop();
+    void loop(uint32_t millis);
 
     /**
      * Push the door opener button down by moving the servo arm.

src/controller.cpp

@@ -1,33 +1,58 @@
 #include "controller.h"
-#include "config.h"
-#include "fresh.h"
 #include "crypto.h"
+#include "config.h"
 
-SesameController::SesameController(ServerConnection* server, ServoController* servo, AsyncWebServer* local, TimeCheck* timeCheck, uint8_t remoteDeviceCount) : 
+#include <WiFi.h>
-    server(server), servo(servo), local(local), timeCheck(timeCheck), storage(remoteDeviceCount) {
+
+// The url parameter to send the message to the local server
+constexpr char messageUrlParameter[] = "m";
+
+SesameController::SesameController(uint16_t localWebServerPort, uint8_t remoteDeviceCount) : 
+    storage(remoteDeviceCount), localWebServer(localWebServerPort) {
     
     // Set up response buffer
     responseStatus = (SesameEvent*) responseBuffer;
     responseMessage = (AuthenticatedMessage*) (responseBuffer + 1);
 }
 
-void SesameController::configure() {
+void SesameController::configure(ServoConfiguration servoConfig, ServerConfiguration serverConfig, TimeConfiguration timeConfig, WifiConfiguration wifiConfig, KeyConfiguration keyConfig) {
+    this->wifiConfig = wifiConfig;
+    this->keyConfig = keyConfig;
+
     // Prepare EEPROM for reading and writing
     storage.configure();
+    Serial.println("[INFO] Storage configured");
+    
+    servo.configure(servoConfig);
+    Serial.println("[INFO] Servo configured");
 
     // Direct messages and errors over the websocket to the controller
-    server->setCallbackHandler(this);
+    server.configure(serverConfig, this);
+    Serial.println("[INFO] Server connection configured");
+
+    timeCheck.configure(timeConfig);
+
     
     // Direct messages from the local web server to the controller
-    local->on("/message", HTTP_POST, [this] (AsyncWebServerRequest *request) { 
+    localWebServer.on("/message", HTTP_POST, [this] (AsyncWebServerRequest *request) { 
         this->handleLocalMessage(request); 
         this->sendPreparedLocalResponse(request);
     });
 
+    Serial.println("[INFO] Local web server configured");
+
     //storage.resetMessageCounters();
     storage.printMessageCounters();
 }
 
+void SesameController::loop(uint32_t millis) {
+    server.loop();
+    servo.loop(millis);
+
+    ensureWiFiConnection(millis);
+    ensureWebSocketConnection();
+}
+
 // MARK: Local
 
 void 
@@ -69,7 +94,7 @@ void SesameController::handleServerMessage(uint8_t* payload, size_t length) {
 }
 
 void SesameController::sendPreparedServerResponse() {
-    server->sendResponse(responseBuffer, responseSize);
+    server.sendResponse(responseBuffer, responseSize);
     Serial.printf("[INFO] Server response %u (%u bytes)\n", responseBuffer[0], responseSize);
 }
 
@@ -90,7 +115,7 @@ void SesameController::processMessage(AuthenticatedMessage* message) {
  * @return The response to signal to the server.
  */
 SesameEvent SesameController::verifyAndProcessReceivedMessage(AuthenticatedMessage* message) {
-    if (!isAuthenticMessage(message, remoteKey, keySize)) {
+    if (!isAuthenticMessage(message, keyConfig.remoteKey, keySize)) {
         return SesameEvent::MessageAuthenticationFailed;
     }
     if (!storage.isDeviceIdValid(message->message.device)) {
@@ -99,13 +124,13 @@ SesameEvent SesameController::verifyAndProcessReceivedMessage(AuthenticatedMessa
     if (!storage.isMessageCounterValid(message->message.id, message->message.device)) {
         return SesameEvent::MessageCounterInvalid;
     }
-    if (!timeCheck->isMessageTimeAcceptable(message->message.time)) {
+    if (!timeCheck.isMessageTimeAcceptable(message->message.time)) {
         return SesameEvent::MessageTimeMismatch;
     }
 
     storage.didUseMessageCounter(message->message.id, message->message.device);
     // Move servo
-    servo->pressButton();
+    servo.pressButton();
     Serial.printf("[Info] Accepted message %d\n", message->message.id);
     return SesameEvent::MessageAccepted;
 }
@@ -127,16 +152,42 @@ uint16_t SesameController::prepareResponseBuffer(SesameEvent event, uint8_t devi
     if (!allowMessageResponse(event)) {
         return 1;
     }
-    responseMessage->message.time = timeCheck->getEpochTime();
+    responseMessage->message.time = timeCheck.getEpochTime();
     responseMessage->message.id = storage.getNextMessageCounter(deviceId);
     responseMessage->message.device = deviceId;
-    if (!authenticateMessage(responseMessage, localKey, keySize)) {
+    if (!authenticateMessage(responseMessage, keyConfig.localKey, keySize)) {
         *responseStatus = SesameEvent::InvalidResponseAuthentication;
         return 1;
     }
     return 1 + AUTHENTICATED_MESSAGE_SIZE;
 }
 
+// MARK: Reconnecting
+
+void SesameController::ensureWiFiConnection(uint32_t millis) {
+    static uint32_t nextWifiReconnect = 0;
+    // Reconnect to WiFi
+    if(millis > nextWifiReconnect && WiFi.status() != WL_CONNECTED) {
+        Serial.println("[INFO] Reconnecting WiFi...");
+        WiFi.setHostname(wifiConfig.networkName);
+        WiFi.begin(wifiConfig.ssid, wifiConfig.password);
+        isReconnecting = true;
+        nextWifiReconnect = millis + wifiConfig.reconnectInterval;
+    }
+}
+
+void SesameController::ensureWebSocketConnection() {
+    if (isReconnecting && WiFi.status() == WL_CONNECTED) {
+        isReconnecting = false;
+        Serial.print("WiFi IP address: ");
+        Serial.println(WiFi.localIP());
+        server.connect();
+        timeCheck.startNTP();
+        timeCheck.printLocalTime();
+        localWebServer.begin();
+    }
+}
+
 // MARK: Helper
 
 // Based on https://stackoverflow.com/a/23898449/266720

src/fresh.cpp

@@ -3,12 +3,14 @@
 #include <Arduino.h> // configTime()
 #include <time.h>
 
-TimeCheck::TimeCheck(uint32_t allowedTimeOffset) {
+TimeCheck::TimeCheck() { }
-    allowedOffset = allowedTimeOffset;
+
+void TimeCheck::configure(TimeConfiguration configuration) {
+    config = configuration;
 }
 
-void TimeCheck::configureNTP(int32_t offsetToGMT, int32_t offsetDaylightSavings, const char* serverUrl) {
+void TimeCheck::startNTP() {
-    configTime(offsetToGMT, offsetDaylightSavings, serverUrl);
+    configTime(config.offsetToGMT, config.offsetDaylightSavings, config.ntpServerUrl);
 }
 
 void TimeCheck::printLocalTime() {
@@ -37,10 +39,10 @@ bool TimeCheck::isMessageTimeAcceptable(uint32_t t) {
         Serial.println("No epoch time available");
         return false;
     }
-    if (t > localTime + allowedOffset) {
+    if (t > localTime + config.allowedTimeOffset) {
         return false;
     }
-    if (t < localTime - allowedOffset) {
+    if (t < localTime - config.allowedTimeOffset) {
         return false;
     }
     return true;

src/main.cpp

@@ -6,87 +6,61 @@
  * physical button.
  */
 #include <Arduino.h>
-#include <WiFi.h>
-#include <ESPAsyncWebServer.h>
 
-#include "crypto.h"
-#include "fresh.h"
 #include "message.h"
 #include "server.h"
 #include "servo.h"
-#include "config.h"
 #include "controller.h"
+#include "config.h"
 
-/* Global variables */
+SesameController controller(localWebServerPort, remoteDeviceCount);
-
-TimeCheck timeCheck{};
-
-ServerConnection server(serverUrl, serverPort, serverPath);
-
-ServoController servo{};
-
-AsyncWebServer local(localPort);
-
-SesameController controller(&server, &servo, &local, &timeCheck, remoteDeviceCount);
-
-// Forward declare monitoring functions
-void ensureWiFiConnection(uint32_t time);
-void ensureWebSocketConnection(uint32_t time);
-
-/* Logic */
 
 void setup() {
     Serial.begin(serialBaudRate);
     Serial.setDebugOutput(true);
     Serial.println("[INFO] Device started");
 
-    ServoConfiguration servoConfig;
+    ServoConfiguration servoConfig {
-    servoConfig.pwmTimer = pwmTimer;
+        .pwmTimer = pwmTimer,
-    servoConfig.pwmFrequency = servoFrequency;
+        .pwmFrequency = servoFrequency,
-    servoConfig.pin = servoPin;
+        .pin = servoPin,
-    servoConfig.openDuration = lockOpeningDuration;
+        .openDuration = lockOpeningDuration,
-    servoConfig.pressedValue = servoPressedState;
+        .pressedValue = servoPressedState,
-    servoConfig.releasedValue = servoReleasedState;
+        .releasedValue = servoReleasedState,
+    };
 
-    servo.configure(servoConfig);
+    ServerConfiguration serverConfig {
-    Serial.println("[INFO] Servo configured");
+        .url = serverUrl,
+        .port = serverPort,
+        .path = serverPath,
+        .key = serverAccessKey,
+        .reconnectTime = 5000,
+    };
 
-    controller.configure();
+    TimeConfiguration timeConfig {
+        .offsetToGMT = timeOffsetToGMT,
+        .offsetDaylightSavings = timeOffsetDaylightSavings,
+        .ntpServerUrl = ntpServerUrl,
+        .allowedTimeOffset = 60,
+    };
+
+    WifiConfiguration wifiConfig {
+        .ssid = wifiSSID,
+        .password = wifiPassword,
+        .networkName = networkName,
+        .reconnectInterval = wifiReconnectInterval,
+    };
+
+    KeyConfiguration keyConfig {
+        .remoteKey = remoteKey,
+        .localKey = localKey,
+    };
+
+    controller.configure(servoConfig, serverConfig, timeConfig, wifiConfig, keyConfig);
 }
 
 void loop() {
     uint32_t time = millis();
 
-    server.loop();
+    controller.loop(time);
-    servo.loop();
-
-    ensureWiFiConnection(time);
-    ensureWebSocketConnection(time);
-}
-
-uint32_t nextWifiReconnect = 0;
-bool isReconnecting = false;
-
-void ensureWiFiConnection(uint32_t time) {
-    // Reconnect to WiFi
-    if(time > nextWifiReconnect && WiFi.status() != WL_CONNECTED) {
-        Serial.println("[INFO] Reconnecting WiFi...");
-        WiFi.setHostname(networkName);
-        WiFi.begin(wifiSSID, wifiPassword);
-        isReconnecting = true;
-        nextWifiReconnect = time + wifiReconnectInterval;
-    }
-}
-
-void ensureWebSocketConnection(uint32_t time) {
-    if (isReconnecting && WiFi.status() == WL_CONNECTED) {
-        isReconnecting = false;
-        Serial.println("IP address: ");
-        Serial.println(WiFi.localIP());
-        Serial.println("[INFO] WiFi connected, opening socket");
-        server.connect(serverAccessKey);
-        timeCheck.configureNTP(timeOffsetToGMT, timeOffsetDaylightSavings, ntpServerUrl);
-        timeCheck.printLocalTime();
-        local.begin();
-    }
 }

src/server.cpp

@@ -4,12 +4,14 @@ constexpr int32_t pingInterval = 10000;
 constexpr uint32_t pongTimeout = 5000;
 uint8_t disconnectTimeoutCount = 3;
 
-ServerConnection::ServerConnection(const char* url, int port, const char* path) : 
+ServerConnection::ServerConnection() { }
-    url(url), port(port), path(path) {
 
+void ServerConnection::configure(ServerConfiguration configuration, ServerConnectionCallbacks *callbacks) {
+    controller = callbacks;
+    this->configuration = configuration;
 }
 
-void ServerConnection::connect(const char* key, uint32_t reconnectTime) {
+void ServerConnection::connect() {
     if (socketIsConnected) {
         return;
     }
@@ -17,25 +19,20 @@ void ServerConnection::connect(const char* key, uint32_t reconnectTime) {
         Serial.println("[ERROR] No callbacks set for server");
         return;
     }
-    this->key = key;
 
-    webSocket.beginSSL(url, port, path);
+    webSocket.beginSSL(configuration.url, configuration.port, configuration.path);
 
     std::function<void(WStype_t, uint8_t *, size_t)> f = [this](WStype_t type, uint8_t *payload, size_t length) {
         this->webSocketEventHandler(type, payload, length);
     };
     webSocket.onEvent(f);
-    webSocket.setReconnectInterval(reconnectTime);
+    webSocket.setReconnectInterval(configuration.reconnectTime);
 }
 
 void ServerConnection::loop() {
     webSocket.loop();
 }
 
-void ServerConnection::setCallbackHandler(ServerConnectionCallbacks* callbacks) {
-    controller = callbacks;
-}
-
 void ServerConnection::webSocketEventHandler(WStype_t type, uint8_t * payload, size_t length) {
 switch(type) {
     case WStype_DISCONNECTED:
@@ -44,7 +41,7 @@ switch(type) {
         break;
     case WStype_CONNECTED:
         socketIsConnected = true;
-        webSocket.sendTXT(key);
+        webSocket.sendTXT(configuration.key);
         Serial.printf("[INFO] Socket connected to url: %s\n", payload);
         webSocket.enableHeartbeat(pingInterval, pongTimeout, disconnectTimeoutCount);
         break;

src/servo.cpp

@@ -25,8 +25,8 @@ void ServoController::releaseButton() {
     buttonIsPressed = false;
 }
 
-void ServoController::loop() {
+void ServoController::loop(uint32_t millis) {
-    if (buttonIsPressed && millis() > openingEndTime) {
+    if (buttonIsPressed && millis > openingEndTime) {
         releaseButton();
     }
 }