ESP32-PaxCounter/src/macsniff.cpp
2020-03-29 18:11:24 +02:00

139 lines
4.2 KiB
C++

// Basic Config
#include "globals.h"
#include "macsniff.h"
#if (VENDORFILTER)
#include "vendor_array.h"
#endif
// Local logging tag
static const char TAG[] = __FILE__;
uint16_t salt;
uint16_t get_salt(void) {
salt = (uint16_t)random(65536); // get new 16bit random for salting hashes
return salt;
}
int8_t isBeacon(uint64_t mac) {
it = std::find(beacons.begin(), beacons.end(), mac);
if (it != beacons.end())
return std::distance(beacons.begin(), it);
else
return -1;
}
// Display a key
void printKey(const char *name, const uint8_t *key, uint8_t len, bool lsb) {
const uint8_t *p;
char keystring[len + 1] = "", keybyte[3];
for (uint8_t i = 0; i < len; i++) {
p = lsb ? key + len - i - 1 : key + i;
snprintf(keybyte, 3, "%02X", *p);
strncat(keystring, keybyte, 2);
}
ESP_LOGI(TAG, "%s: %s", name, keystring);
}
uint64_t macConvert(uint8_t *paddr) {
uint64_t *mac;
mac = (uint64_t *)paddr;
return (__builtin_bswap64(*mac) >> 16);
}
bool mac_add(uint8_t *paddr, int8_t rssi, bool sniff_type) {
if (!salt) // ensure we have salt (appears after radio is turned on)
return false;
char buff[10]; // temporary buffer for printf
bool added = false;
int8_t beaconID; // beacon number in test monitor mode
uint16_t hashedmac; // temporary buffer for generated hash value
uint32_t *mac; // temporary buffer for shortened MAC
// 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.
// this gets MAC in msb (= reverse) order, but doesn't matter for hashing it.
mac = (uint32_t *)(paddr + 2);
#if (VENDORFILTER)
uint32_t *oui; // temporary buffer for vendor OUI
oui = (uint32_t *)paddr;
// use OUI vendor filter list only on Wifi, not on BLE
if ((sniff_type == MAC_SNIFF_BLE) ||
std::find(vendors.begin(), vendors.end(), __builtin_bswap32(*oui) >> 8) !=
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
snprintf(buff, sizeof(buff), "%08X",
*mac + (uint32_t)salt); // convert unsigned 32-bit salted MAC
// to 8 digit hex string
hashedmac = rokkit(&buff[3], 5); // hash MAC 8 digit -> 5 digit
auto newmac = macs.insert(hashedmac); // add hashed MAC, if new unique
added = newmac.second ? true
: false; // true if hashed MAC is unique in container
// Count only if MAC was not yet seen
if (added) {
// increment counter and one blink led
if (sniff_type == MAC_SNIFF_WIFI) {
macs_wifi++; // increment Wifi MACs counter
#if (HAS_LED != NOT_A_PIN) || defined(HAS_RGB_LED)
blink_LED(COLOR_GREEN, 50);
#endif
}
#if (BLECOUNTER)
else if (sniff_type == MAC_SNIFF_BLE) {
macs_ble++; // increment BLE Macs counter
#if (HAS_LED != NOT_A_PIN) || defined(HAS_RGB_LED)
blink_LED(COLOR_MAGENTA, 50);
#endif
}
#endif
// in beacon monitor mode check if seen MAC is a known beacon
if (cfg.monitormode) {
beaconID = isBeacon(macConvert(paddr));
if (beaconID >= 0) {
ESP_LOGI(TAG, "Beacon ID#%d detected", beaconID);
#if (HAS_LED != NOT_A_PIN) || defined(HAS_RGB_LED)
blink_LED(COLOR_WHITE, 2000);
#endif
payload.reset();
payload.addAlarm(rssi, beaconID);
SendPayload(BEACONPORT, prio_high);
}
};
} // added
// Log scan result
ESP_LOGV(TAG,
"%s %s RSSI %ddBi -> salted MAC %s -> Hash %04X -> WiFi:%d "
"BLTH:%d -> "
"%d Bytes left",
added ? "new " : "known",
sniff_type == MAC_SNIFF_WIFI ? "WiFi" : "BLTH", rssi, buff,
hashedmac, macs_wifi, macs_ble, getFreeRAM());
#if (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)
}