esp-firewall/ESPFirewall/src/main.cpp

#include "theSecrets.h"
#include "theCerts.h"

#ifdef ESP32
#include "WiFi.h"
#include "esp_wifi.h"
#elif defined(ESP8266)
#include "ESP8266WiFi.h"
#endif

#include "Firewall.hpp"
#include "API.hpp"

fw::Firewall *firewall;
fw::API *firewallApi;

WiFiServer wifiServer(80);

typedef struct
{
  unsigned frame_ctrl : 16;
  unsigned duration_id : 16;
  uint8_t addr1[6]; /* receiver address */
  uint8_t addr2[6]; /* sender address */
  uint8_t addr3[6]; /* filtering address */
  unsigned sequence_ctrl : 16;
  uint8_t addr4[6]; /* optional */
} wifi_ieee80211_mac_hdr_t;

typedef struct
{
  wifi_ieee80211_mac_hdr_t hdr;
  uint8_t payload[0]; /* network data ended with 4 bytes csum (CRC32) */
} wifi_ieee80211_packet_t;

void connectToWifi()
{
  WiFi.begin(ssid, psk);
  while (WiFi.status() != WL_CONNECTED)
  {
    delay(200);
  }
}

void handle_wifi_events(WiFiEvent_t event, WiFiEventInfo_t info)
{
  Serial.print("[WiFi] ");
  switch (event)
  {
  case ARDUINO_EVENT_WIFI_STA_START:
    Serial.printf("Attempting to connect to WPA SSID: %s\n", ssid);
    break;
  case ARDUINO_EVENT_WIFI_STA_CONNECTED:
    Serial.println("connected");
    break;
  case ARDUINO_EVENT_WIFI_STA_DISCONNECTED:
    Serial.println("disconnected");
    break;
  case ARDUINO_EVENT_WIFI_STA_GOT_IP:
    Serial.print("IP address: ");
    Serial.println(WiFi.localIP());
    break;
  default:
    Serial.println(event);
  }
}

const char *wifi_sniffer_packet_type2str(wifi_promiscuous_pkt_type_t type)
{
  switch (type)
  {
  case WIFI_PKT_DATA:
    return "DATA";
  default:
  case WIFI_PKT_MISC:
    return "MISC";
  }
}

void wifi_sniffer_packet_handler(void *buff, wifi_promiscuous_pkt_type_t type)
{
  if (type != WIFI_PKT_MGMT)
    return;

  const wifi_promiscuous_pkt_t *ppkt = (wifi_promiscuous_pkt_t *)buff;
  const wifi_ieee80211_packet_t *ipkt = (wifi_ieee80211_packet_t *)ppkt->payload;
  const wifi_ieee80211_mac_hdr_t *hdr = &ipkt->hdr;

  printf("PACKET TYPE=%s, CHAN=%02d, RSSI=%02d,"
         " ADDR1=%02x:%02x:%02x:%02x:%02x:%02x,"
         " ADDR2=%02x:%02x:%02x:%02x:%02x:%02x,"
         " ADDR3=%02x:%02x:%02x:%02x:%02x:%02x\n",
         wifi_sniffer_packet_type2str(type),
         ppkt->rx_ctrl.channel,
         ppkt->rx_ctrl.rssi,
         /* ADDR1 */
         hdr->addr1[0], hdr->addr1[1], hdr->addr1[2],
         hdr->addr1[3], hdr->addr1[4], hdr->addr1[5],
         /* ADDR2 */
         hdr->addr2[0], hdr->addr2[1], hdr->addr2[2],
         hdr->addr2[3], hdr->addr2[4], hdr->addr2[5],
         /* ADDR3 */
         hdr->addr3[0], hdr->addr3[1], hdr->addr3[2],
         hdr->addr3[3], hdr->addr3[4], hdr->addr3[5]);
}

void setup_wifi()
{
  WiFi.mode(WIFI_STA);
  WiFi.onEvent(handle_wifi_events, ARDUINO_EVENT_MAX);
  connectToWifi();
  esp_wifi_set_promiscuous(true);
  esp_wifi_set_promiscuous_rx_cb(&wifi_sniffer_packet_handler);
}

void setup()
{
  Serial.begin(115200);
  setup_wifi();
  firewall = new fw::Firewall();
  firewallApi = new fw::API(firewall, cert, key, username, password);
  wifiServer.begin();
}

void loop()
{
  firewallApi->handle_client();
  WiFiClient client = wifiServer.available();
  if (client)
  {
    if (firewall->is_client_allowed(client))
    {
      Serial.println("allowed");
      client.stop();
    }
    else
    {
      Serial.println("rejected");
      client.flush();
    }
  }
}