ESP32-PaxCounter/src/macsniff.cpp
2018-04-17 22:42:06 +02:00

119 lines
4.8 KiB
C++

// Basic Config
#include "globals.h"
#ifdef VENDORFILTER
#include <array>
#include <algorithm>
#include "vendor_array.h"
#endif
// Local logging tag
static const char *TAG = "macsniff";
// defined in main.cpp
void set_LED (uint16_t set_color, uint16_t set_blinkduration, uint16_t set_interval, uint8_t set_count);
static wifi_country_t wifi_country = {.cc=WIFI_MY_COUNTRY, .schan=WIFI_CHANNEL_MIN, .nchan=WIFI_CHANNEL_MAX, .policy=WIFI_COUNTRY_POLICY_MANUAL};
uint16_t salt;
uint16_t salt_reset(void) {
salt = random(65536); // get new 16bit random for salting hashes
return salt;
}
bool mac_add(uint8_t *paddr, int8_t rssi, bool sniff_type) {
char buff[16]; // temporary buffer for printf
bool added = false;
uint32_t addr2int;
uint32_t vendor2int;
uint16_t hashedmac;
// only last 3 MAC Address bytes are used for MAC Address Anonymization
// but since it's uint32 we take 4 bytes to avoid 1st value to be 0
addr2int = ( (uint32_t)paddr[2] ) | ( (uint32_t)paddr[3] << 8 ) | ( (uint32_t)paddr[4] << 16 ) | ( (uint32_t)paddr[5] << 24 );
#ifdef VENDORFILTER
vendor2int = ( (uint32_t)paddr[2] ) | ( (uint32_t)paddr[1] << 8 ) | ( (uint32_t)paddr[0] << 16 );
// use OUI vendor filter list only on Wifi, not on BLE
if ( (sniff_type==MAC_SNIFF_BLE) || std::find(vendors.begin(), vendors.end(), vendor2int) != vendors.end() ) {
#endif
// salt and hash MAC, and if new unique one, store identifier in container and increment counter on display
// https://en.wikipedia.org/wiki/MAC_Address_Anonymization
addr2int += (uint32_t) salt; // add 16-bit salt to pseudo MAC
snprintf(buff, sizeof(buff), "%08X", addr2int); // convert unsigned 32-bit salted MAC to 8 digit hex string
hashedmac = rokkit(&buff[3], 5); // hash MAC last string value, use 5 chars to fit hash in uint16_t container
auto newmac = macs.insert(hashedmac); // add hashed MAC to total container if new unique
added = newmac.second ? true:false; // true if hashed MAC is unique in container
// Insert only if it was not found on global count
if (added) {
if (sniff_type == MAC_SNIFF_WIFI ) {
set_LED(COLOR_GREEN, 20, 0, 1);
wifis.insert(hashedmac); // add hashed MAC to wifi container
}
#ifdef BLECOUNTER
else if (sniff_type == MAC_SNIFF_BLE ) {
set_LED(COLOR_MAGENTA, 20, 0, 1);
bles.insert(hashedmac); // add hashed MAC to BLE container
}
#endif
}
ESP_LOGI(TAG, "%s RSSI %ddBi -> MAC %s -> Hash %04X -> WiFi:%d BLTH:%d %s",
sniff_type==MAC_SNIFF_WIFI ? "WiFi":"BLTH",
rssi, buff, hashedmac,
(int) wifis.size(),
#ifdef BLECOUNTER
(int) bles.size(),
#else
0,
#endif
added ? "new" : "known");
#ifdef VENDORFILTER
} else {
// Very noisy
// ESP_LOGD(TAG, "Filtered MAC %02X:%02X:%02X:%02X:%02X:%02X", paddr[0],paddr[1],paddr[2],paddr[3],paddr[5],paddr[5]);
}
#endif
// True if MAC WiFi/BLE was new
return added; // function returns bool if a new and unique Wifi or BLE mac was counted (true) or not (false)
}
void wifi_sniffer_init(void) {
wifi_init_config_t cfg = WIFI_INIT_CONFIG_DEFAULT();
cfg.nvs_enable = 0; // we don't need any wifi settings from NVRAM
wifi_promiscuous_filter_t filter = {.filter_mask = WIFI_PROMIS_FILTER_MASK_MGMT}; // we need only MGMT frames
ESP_ERROR_CHECK(esp_wifi_init(&cfg)); // configure Wifi with cfg
ESP_ERROR_CHECK(esp_wifi_set_country(&wifi_country)); // set locales for RF and channels
ESP_ERROR_CHECK(esp_wifi_set_storage(WIFI_STORAGE_RAM)); // we don't need NVRAM
ESP_ERROR_CHECK(esp_wifi_set_mode(WIFI_MODE_NULL));
ESP_ERROR_CHECK(esp_wifi_set_promiscuous_filter(&filter)); // set MAC frame filter
ESP_ERROR_CHECK(esp_wifi_set_promiscuous_rx_cb(&wifi_sniffer_packet_handler));
ESP_ERROR_CHECK(esp_wifi_set_promiscuous(true)); // now switch on monitor mode
}
void wifi_sniffer_set_channel(uint8_t channel) {
esp_wifi_set_channel(channel, WIFI_SECOND_CHAN_NONE);
}
void wifi_sniffer_packet_handler(void* buff, wifi_promiscuous_pkt_type_t type) {
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;
if (( cfg.rssilimit == 0 ) || (ppkt->rx_ctrl.rssi > cfg.rssilimit )) { // rssi is negative value
uint8_t *p = (uint8_t *) hdr->addr2;
mac_add(p, ppkt->rx_ctrl.rssi, MAC_SNIFF_WIFI) ;
} else {
ESP_LOGI(TAG, "WiFi RSSI %d -> ignoring (limit: %d)", ppkt->rx_ctrl.rssi, cfg.rssilimit);
}
}