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A fork of esp8266-sniffer to pipe probe requests the serial port in JSON format to be easily used with Node-RED, etc.
#include <ArduinoJson.h>
#include <iostream>
#include <ESP8266WiFi.h> // added this
#include <ESP8266HTTPClient.h> // added this
const char* serial = "YYYY-YYYY-YYYY"; // fake AP serial
const char* networkId = "N_99999999999"; // fake network ID
const float txPower = 20.5; // power in dBm (0 - 20.5)
extern "C" {
#include <user_interface.h>
}
#define DATA_LENGTH 112
#define TYPE_MANAGEMENT 0x00
#define TYPE_CONTROL 0x01
#define TYPE_DATA 0x02
#define SUBTYPE_PROBE_REQUEST 0x04
struct RxControl {
signed rssi:8; // signal intensity of packet
unsigned rate:4;
unsigned is_group:1;
unsigned:1;
unsigned sig_mode:2; // 0:is 11n packet; 1:is not 11n packet;
unsigned legacy_length:12; // if not 11n packet, shows length of packet.
unsigned damatch0:1;
unsigned damatch1:1;
unsigned bssidmatch0:1;
unsigned bssidmatch1:1;
unsigned MCS:7; // if is 11n packet, shows the modulation and code used (range from 0 to 76)
unsigned CWB:1; // if is 11n packet, shows if is HT40 packet or not
unsigned HT_length:16;// if is 11n packet, shows length of packet.
unsigned Smoothing:1;
unsigned Not_Sounding:1;
unsigned:1;
unsigned Aggregation:1;
unsigned STBC:2;
unsigned FEC_CODING:1; // if is 11n packet, shows if is LDPC packet or not.
unsigned SGI:1;
unsigned rxend_state:8;
unsigned ampdu_cnt:8;
unsigned channel:4; //which channel this packet in.
unsigned:12;
};
struct SnifferPacket{
struct RxControl rx_ctrl;
uint8_t data[DATA_LENGTH];
uint16_t cnt;
uint16_t len;
};
static void showMetadata(SnifferPacket *snifferPacket) {
unsigned int frameControl = ((unsigned int)snifferPacket->data[1] << 8) + snifferPacket->data[0];
uint8_t version = (frameControl & 0b0000000000000011) >> 0;
uint8_t frameType = (frameControl & 0b0000000000001100) >> 2;
uint8_t frameSubType = (frameControl & 0b0000000011110000) >> 4;
uint8_t toDS = (frameControl & 0b0000000100000000) >> 8;
uint8_t fromDS = (frameControl & 0b0000001000000000) >> 9;
// Only look for probe request packets
if (frameType != TYPE_MANAGEMENT ||
frameSubType != SUBTYPE_PROBE_REQUEST)
return;
StaticJsonDocument<200> doc;
doc["rssi"] = snifferPacket->rx_ctrl.rssi, DEC;
doc["txPower"] = txPower;
doc["channel"] = wifi_get_channel();
char addr[] = "00:00:00:00:00:00";
getMAC(addr, snifferPacket->data, 10);
doc["clientMac"] = addr;
uint8_t SSID_length = snifferPacket->data[25];
doc["ssid"] = printDataSpan(26, SSID_length, snifferPacket->data);
doc["serial"] = serial;
doc["networkId"] = networkId;
serializeJson(doc, Serial);
// Start a new line
std::cout << std::endl;
}
/**
* Callback for promiscuous mode
*/
static void ICACHE_FLASH_ATTR sniffer_callback(uint8_t *buffer, uint16_t length) {
struct SnifferPacket *snifferPacket = (struct SnifferPacket*) buffer;
showMetadata(snifferPacket);
}
static String printDataSpan(uint16_t start, uint16_t size, uint8_t* data) {
String value = "";
for(uint16_t i = start; i < DATA_LENGTH && i < start+size; i++) {
value.concat(char(data[i]));
}
return value;
}
static void getMAC(char *addr, uint8_t* data, uint16_t offset) {
sprintf(addr, "%02x:%02x:%02x:%02x:%02x:%02x", data[offset+0], data[offset+1], data[offset+2], data[offset+3], data[offset+4], data[offset+5]);
}
#define CHANNEL_HOP_INTERVAL_MS 1000
static os_timer_t channelHop_timer;
/**
* Callback for channel hoping
*/
void channelHop()
{
// hoping channels 1-14
uint8 new_channel = wifi_get_channel() + 1;
if (new_channel > 14)
new_channel = 1;
wifi_set_channel(new_channel);
}
#define DISABLE 0
#define ENABLE 1
void setup() {
Serial.begin(115200);
WiFi.setOutputPower(txPower);
//wifi_set_output_power(txPower);
// set the WiFi chip to "promiscuous" mode aka monitor mode
delay(10);
wifi_set_opmode(STATION_MODE);
wifi_set_channel(1);
wifi_promiscuous_enable(DISABLE);
delay(10);
wifi_set_promiscuous_rx_cb(sniffer_callback);
delay(10);
wifi_promiscuous_enable(ENABLE);
// setup the channel hoping callback timer
os_timer_disarm(&channelHop_timer);
os_timer_setfn(&channelHop_timer, (os_timer_func_t *) channelHop, NULL);
os_timer_arm(&channelHop_timer, CHANNEL_HOP_INTERVAL_MS, 1);
}
void loop() {
delay(10);
}
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