Add local server option

include/base64.h

@@ -0,0 +1,30 @@
+#ifndef UTILITY_BASE64_H_
+#define UTILITY_BASE64_H_
+
+#include <string.h>
+
+/**
+ * @brief Base64 encode function.
+ *
+ * @param[in] *data Pointer to data that will be encoded.
+ * @param[in] data_length Data length.
+ * @param[out] *result Pointer to result, encoded data.
+ * @param[in] max_result_length Maximum result length.
+ *
+ * @return 0 = success, in case of fail value different than 0 is returned.
+ */
+int32_t Base64_encode(const char* data, size_t data_length, char* result, size_t max_result_length);
+
+/**
+ * @brief Base64 decode function.
+ *
+ * @param[in] *in Pointer to data that will be decoded.
+ * @param[in] in_len Input data length.
+ * @param[out] *out Pointer to result data, decoded data.
+ * @param[in] max_out_len Maximum output length.
+ *
+ * @return 0 = success, in case of fail value different than 0 is returned.
+ */
+int32_t Base64_decode(const char* in, size_t in_len, uint8_t* out, size_t max_out_len);
+
+#endif /* UTILITY_BASE64_H_ */

include/example_config.h

@@ -40,9 +40,20 @@ constexpr const char* wifiSSID = "MyWiFi";
 // The WiFi password to connect to the above network
 constexpr const char* wifiPassword = "00000000";
 
+// The name of the device on the network
+constexpr const char* networkName = "Sesame-Device";
+
 // The interval to reconnect to WiFi if the connection is broken
 constexpr uint32_t wifiReconnectInterval = 10000;
 
+/* Local server */
+
+// The port for the local server to directly receive messages over WiFi
+constexpr uint16_t localPort = 80;
+
+// The url parameter to send the message to the local server
+constexpr char messageUrlParameter[] = "m";
+
 
 /* Server */ 
 

include/message.h

@@ -84,4 +84,26 @@ typedef struct {
 
 #define MESSAGE_CONTENT_SIZE sizeof(Message)
 
-#define AUTHENTICATED_MESSAGE_SIZE sizeof(AuthenticatedMessage)
+#define AUTHENTICATED_MESSAGE_SIZE sizeof(AuthenticatedMessage)
+
+/**
+ * An event signaled from the device
+ */
+enum class SesameEvent {
+    TextReceived = 1,
+    UnexpectedSocketEvent = 2,
+    InvalidMessageData = 3,
+    MessageAuthenticationFailed = 4,
+    MessageTimeMismatch = 5,
+    MessageCounterInvalid = 6,
+    MessageAccepted = 7,
+};
+
+/**
+ * @brief A callback for messages received over the socket
+ * 
+ * The first parameter is the received message.
+ * The second parameter is the response to the remote.
+ * The return value is the type of event to respond with.
+ */
+typedef SesameEvent (*MessageCallback)(AuthenticatedMessage*, AuthenticatedMessage*);

include/server.h

@@ -6,28 +6,6 @@
 #include <WiFiClientSecure.h>
 #include <WebSocketsClient.h>
 
-/**
- * An event signaled from the device
- */
-enum class SesameEvent {
-    TextReceived = 1,
-    UnexpectedSocketEvent = 2,
-    InvalidMessageData = 3,
-    MessageAuthenticationFailed = 4,
-    MessageTimeMismatch = 5,
-    MessageCounterInvalid = 6,
-    MessageAccepted = 7,
-};
-
-/**
- * @brief A callback for messages received over the socket
- * 
- * The first parameter is the received message.
- * The second parameter is the response to the remote.
- * The return value is the type of event to respond with.
- */
-typedef SesameEvent (*MessageCallback)(AuthenticatedMessage*, AuthenticatedMessage*);
-
 class ServerConnection {
 
 public:

platformio.ini

@@ -14,5 +14,6 @@ board = az-delivery-devkit-v4
 framework = arduino
 lib_deps = 
 	links2004/WebSockets@^2.3.7
-	madhephaestus/ESP32Servo@^0.11.0
-monitor_speed = 115200
+	madhephaestus/ESP32Servo@^0.13.0
+	ottowinter/ESPAsyncWebServer-esphome@^3.0.0
+monitor_speed = 115200

src/base64.cpp

@@ -0,0 +1,172 @@
+/*
+ * Base64 Decode
+ * Polfosol
+ *
+ * Base64 encoding/decoding (RFC1341)
+ * Copyright (c) 2005-2011, Jouni Malinen <j@w1.fi>
+ *
+ * This software may be distributed under the terms of the BSD license.
+ * See README for more details.
+ *
+ */
+
+// Source code from Polfosol: https://stackoverflow.com/questions/180947/base64-decode-snippet-in-c/13935718
+// Source code from Jouni Malinen: https://web.mit.edu/freebsd/head/contrib/wpa/src/utils/base64.c
+
+
+// Encode/Decode functions are modified by Juraj Ciberlin (jciberlin1@gmail.com) to be MISRA C 2012 compliant
+
+#include "base64.h"
+
+int32_t
+Base64_encode(const char* data, size_t data_length, char* result, size_t max_result_length) {
+    int32_t success = 0;
+    const uint8_t base64_table[65] = {
+        (uint8_t)'A', (uint8_t)'B', (uint8_t)'C', (uint8_t)'D',
+        (uint8_t)'E', (uint8_t)'F', (uint8_t)'G', (uint8_t)'H',
+        (uint8_t)'I', (uint8_t)'J', (uint8_t)'K', (uint8_t)'L',
+        (uint8_t)'M', (uint8_t)'N', (uint8_t)'O', (uint8_t)'P',
+        (uint8_t)'Q', (uint8_t)'R', (uint8_t)'S', (uint8_t)'T',
+        (uint8_t)'U', (uint8_t)'V', (uint8_t)'W', (uint8_t)'X',
+        (uint8_t)'Y', (uint8_t)'Z', (uint8_t)'a', (uint8_t)'b',
+        (uint8_t)'c', (uint8_t)'d', (uint8_t)'e', (uint8_t)'f',
+        (uint8_t)'g', (uint8_t)'h', (uint8_t)'i', (uint8_t)'j',
+        (uint8_t)'k', (uint8_t)'l', (uint8_t)'m', (uint8_t)'n',
+        (uint8_t)'o', (uint8_t)'p', (uint8_t)'q', (uint8_t)'r',
+        (uint8_t)'s', (uint8_t)'t', (uint8_t)'u', (uint8_t)'v',
+        (uint8_t)'w', (uint8_t)'x', (uint8_t)'y', (uint8_t)'z',
+        (uint8_t)'0', (uint8_t)'1', (uint8_t)'2', (uint8_t)'3',
+        (uint8_t)'4', (uint8_t)'5', (uint8_t)'6', (uint8_t)'7',
+        (uint8_t)'8', (uint8_t)'9', (uint8_t)'+', (uint8_t)'/',
+        (uint8_t)'\0'
+    };
+    uint8_t* out;
+    const uint8_t* in = (const uint8_t*) data;
+
+    size_t len = 4U * ((data_length + 2U) / 3U);
+
+    if (len < data_length) {
+        success = 1;
+    }
+
+    if (success == 0) {
+        size_t current_length = 0U;
+        size_t in_position = 0U;
+        out = (uint8_t*)&result[0];
+        uint8_t* pos = out;
+        while ((data_length - in_position) >= 3U) {
+            current_length += 4U;
+            if (current_length > max_result_length) {
+                success = 1;
+                break;
+            }
+            *pos = base64_table[in[0] >> 2];
+            ++pos;
+            *pos = base64_table[((in[0] & 0x03U) << 4) | (in[1] >> 4)];
+            ++pos;
+            *pos = base64_table[((in[1] & 0x0FU) << 2) | (in[2] >> 6)];
+            ++pos;
+            *pos = base64_table[in[2] & 0x3FU];
+            ++pos;
+            ++in;
+            ++in;
+            ++in;
+            in_position += 3U;
+        }
+
+        if ((success == 0) && ((data_length - in_position) != 0U)) {
+            current_length += 4U;
+            if (current_length > max_result_length) {
+                success = 1;
+            }
+
+            if (success == 0) {
+                *pos = base64_table[in[0] >> 2];
+                ++pos;
+                if ((data_length - in_position) == 1U) {
+                    *pos = base64_table[(in[0] & 0x03U) << 4];
+                    ++pos;
+                    *pos = (uint8_t)'=';
+                    ++pos;
+                } else {
+                    *pos = base64_table[((in[0] & 0x03U) << 4) | (in[1] >> 4)];
+                    ++pos;
+                    *pos = base64_table[(in[1] & 0x0FU) << 2];
+                    ++pos;
+                }
+                *pos = (uint8_t)'=';
+                ++pos;
+            }
+        }
+
+        *pos = (uint8_t)'\0';
+    }
+
+    return success;
+}
+
+int32_t
+Base64_decode(const char* in, size_t in_len, uint8_t* out, size_t max_out_len) {
+    int32_t success = 0;
+    const uint32_t base64_index[256] = {
+        0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U,
+        0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U,
+        0U, 0U, 0U, 62U, 63U, 62U, 62U, 63U, 52U, 53U, 54U, 55U, 56U, 57U, 58U, 59U, 60U,
+        61U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 1U, 2U, 3U, 4U, 5U, 6U, 7U, 8U, 9U, 10U, 11U,
+        12U, 13U, 14U, 15U, 16U, 17U, 18U, 19U, 20U, 21U, 22U, 23U, 24U, 25U, 0U, 0U, 0U,
+        0U, 63U, 0U, 26U, 27U, 28U, 29U, 30U, 31U, 32U, 33U, 34U, 35U, 36U, 37U, 38U, 39U,
+        40U, 41U, 42U, 43U, 44U, 45U, 46U, 47U, 48U, 49U, 50U, 51U, 0U, 0U, 0U, 0U, 0U, 0U,
+        0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U,
+        0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U,
+        0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U,
+        0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U,
+        0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U,
+        0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U,
+        0U
+    };
+    const uint8_t* in_data_uchar = (const uint8_t*)in;
+    bool pad_bool = (in_len > 0U) && (((in_len % 4U) != 0U) || (in_data_uchar[in_len - 1U] == (uint8_t)'='));
+    uint32_t pad_uint = 0U;
+    if (pad_bool) {
+        pad_uint = 1U;
+    }
+    const size_t len = (((in_len + 3U) / 4U) - pad_uint) * 4U;
+    const size_t out_len = ((len / 4U) * 3U) + pad_uint;
+
+    if (out_len > max_out_len) {
+        success = 1;
+    }
+
+    if (len == 0U) {
+        success = 1;
+    }
+
+    if (success == 0) {
+        size_t j = 0U;
+        for (size_t i = 0U; i < len; i += 4U) {
+            uint32_t n = (base64_index[in_data_uchar[i]] << 18U) | (base64_index[in_data_uchar[i + 1U]] << 12U) |
+                         (base64_index[in_data_uchar[i + 2U]] << 6U) | (base64_index[in_data_uchar[i + 3U]]);
+            out[j] = (uint8_t)(n >> 16U);
+            ++j;
+            out[j] = (uint8_t)((n >> 8U) & 0xFFU);
+            ++j;
+            out[j] = (uint8_t)(n & 0xFFU);
+            ++j;
+        }
+        if (pad_bool) {
+            uint32_t n = (base64_index[in_data_uchar[len]] << 18U) | (base64_index[in_data_uchar[len + 1U]] << 12U);
+            out[out_len - 1U] = (uint8_t)(n >> 16U);
+
+            if ((in_len > (len + 2U)) && (in_data_uchar[len + 2U] != (uint8_t)'=')) {
+                if ((out_len + 1U) > max_out_len) {
+                    success = 1;
+                } else {
+                    n |= base64_index[in_data_uchar[len + 2U]] << 6U;
+                    out[out_len] = (uint8_t)((n >> 8U) & 0xFFU);
+                }
+            }
+        }
+    }
+
+    return success;
+}

src/main.cpp

@@ -7,6 +7,7 @@
  */
 #include <Arduino.h>
 #include <WiFi.h>
+#include <ESPAsyncWebServer.h>
 
 #include "crypto.h"
 #include "fresh.h"
@@ -14,6 +15,7 @@
 #include "server.h"
 #include "servo.h"
 #include "config.h"
+#include "base64.h"
 
 /* Global variables */
 
@@ -21,10 +23,23 @@ ServerConnection server(serverUrl, serverPort, serverPath);
 
 ServoController servo(pwmTimer, servoFrequency, servoPin);
 
+AsyncWebServer local(localPort);
+
+// The buffer to hold a received message while it is read
+uint8_t receivedMessageBuffer[AUTHENTICATED_MESSAGE_SIZE];
+
 /* Event callbacks */
 
 SesameEvent handleReceivedMessage(AuthenticatedMessage* payload, AuthenticatedMessage* response);
 
+// Forward declare monitoring functions
+void ensureWiFiConnection(uint32_t time);
+void ensureWebSocketConnection(uint32_t time);
+
+void sendFailureResponse(AsyncWebServerRequest *request, SesameEvent event);
+void sendMessageResponse(AsyncWebServerRequest *request, SesameEvent event, AuthenticatedMessage* message);
+void sendResponse(AsyncWebServerRequest *request, uint8_t* buffer, uint8_t size);
+
 /* Logic */
 
 void setup() {
@@ -40,6 +55,26 @@ void setup() {
     printMessageCounter();
 
     server.onMessage(handleReceivedMessage);
+
+    local.on("/message", HTTP_POST, [] (AsyncWebServerRequest *request) {
+        if (!request->hasParam(messageUrlParameter)) {
+            Serial.println("Missing url parameter");
+            sendFailureResponse(request, SesameEvent::InvalidMessageData);
+            return;
+        }
+        String encoded = request->getParam(messageUrlParameter)->value();
+        int res = Base64_decode(encoded.c_str(),encoded.length(), receivedMessageBuffer, AUTHENTICATED_MESSAGE_SIZE);
+        if (res) {
+            Serial.printf("Invalid message length (%d)\n", res);
+            sendFailureResponse(request, SesameEvent::InvalidMessageData);
+            return;
+        }
+        // Process received message
+        AuthenticatedMessage* message = (AuthenticatedMessage*) receivedMessageBuffer;
+        AuthenticatedMessage responseMessage;
+        SesameEvent event = handleReceivedMessage(message, &responseMessage);
+        sendMessageResponse(request, event, &responseMessage);
+    });
 }
 
 uint32_t nextWifiReconnect = 0;
@@ -50,20 +85,33 @@ void loop() {
 
     server.loop();
     servo.loop();
-    
+
+    ensureWiFiConnection(time);
+    ensureWebSocketConnection(time);
+}
+
+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.connectSSL(serverAccessKey);
         configureNTP(timeOffsetToGMT, timeOffsetDaylightSavings, ntpServerUrl);
         printLocalTime();
+        local.begin();
     }
 }
 
@@ -109,3 +157,21 @@ SesameEvent handleReceivedMessage(AuthenticatedMessage* message, AuthenticatedMe
     }
     return event;
 }
+
+
+void sendFailureResponse(AsyncWebServerRequest *request, SesameEvent event) {
+    uint8_t response = static_cast<uint8_t>(event);
+    sendResponse(request, &response, 1);
+}
+
+void sendMessageResponse(AsyncWebServerRequest *request, SesameEvent event, AuthenticatedMessage* message) {
+    uint8_t response[AUTHENTICATED_MESSAGE_SIZE+1];
+    response[0] = static_cast<uint8_t>(event);
+    memcpy(response+1, (uint8_t*) message, AUTHENTICATED_MESSAGE_SIZE);
+    sendResponse(request, response, AUTHENTICATED_MESSAGE_SIZE+1);
+}
+
+void sendResponse(AsyncWebServerRequest *request, uint8_t* buffer, uint8_t size) {
+    request->send_P(200, "application/octet-stream", buffer, size);
+    Serial.printf("[INFO] Local response %d\n", buffer[0]);
+}