Getting MAC address in Android 6.0

Question

I\'m developing an app that gets the MAC address of the device, but since Android 6.0 my code doesn\'t work, giving me an incorrect value.

Here\'s my code...

Answer 1

Use wifiInfo.getBSSID() to get Mac Address of AccessPoint instead of getMacAddress method.

Answer 2

I try to get mac address with 2 methods, first by Interface and if its failed, i get it by file system, but you need to enable wifi to access the file.

//Android 6.0 : Access to mac address from WifiManager forbidden
    private static final String marshmallowMacAddress = "02:00:00:00:00:00";
    private static final String fileAddressMac = "/sys/class/net/wlan0/address";    

public static String recupAdresseMAC(WifiManager wifiMan) {
        WifiInfo wifiInf = wifiMan.getConnectionInfo();

        if(wifiInf.getMacAddress().equals(marshmallowMacAddress)){
            String ret = null;
            try {
                ret= getAdressMacByInterface();
                if (ret != null){
                    return ret;
                } else {
                    ret = getAddressMacByFile(wifiMan);
                    return ret;
                }
            } catch (IOException e) {
                Log.e("MobileAccess", "Erreur lecture propriete Adresse MAC");
            } catch (Exception e) {
                Log.e("MobileAcces", "Erreur lecture propriete Adresse MAC ");
            }
        } else{
            return wifiInf.getMacAddress();
        }
        return marshmallowMacAddress;
    }

private static String getAdressMacByInterface(){
        try {
            List<NetworkInterface> all = Collections.list(NetworkInterface.getNetworkInterfaces());
            for (NetworkInterface nif : all) {
                if (nif.getName().equalsIgnoreCase("wlan0")) {
                    byte[] macBytes = nif.getHardwareAddress();
                    if (macBytes == null) {
                        return "";
                    }

                    StringBuilder res1 = new StringBuilder();
                    for (byte b : macBytes) {
                        res1.append(String.format("%02X:",b));
                    }

                    if (res1.length() > 0) {
                        res1.deleteCharAt(res1.length() - 1);
                    }
                    return res1.toString();
                }
            }

        } catch (Exception e) {
            Log.e("MobileAcces", "Erreur lecture propriete Adresse MAC ");
        }
        return null;
    }

private static String getAddressMacByFile(WifiManager wifiMan) throws Exception {
        String ret;
        int wifiState = wifiMan.getWifiState();

        wifiMan.setWifiEnabled(true);
        File fl = new File(fileAddressMac);
        FileInputStream fin = new FileInputStream(fl);
        ret = convertStreamToString(fin);
        fin.close();

        boolean enabled = WifiManager.WIFI_STATE_ENABLED == wifiState;
        wifiMan.setWifiEnabled(enabled);
        return ret;
    }

Add this line to your manifest.

<uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
    <uses-permission android:name="android.permission.CHANGE_WIFI_STATE" />

I recommend you to persist your mac address in your preferences like here

mac = activity.getSharedPreferences("MAC_ADDRESS", Context.MODE_PRIVATE).getString("MAC_ADDRESS", "");
                if(mac == null || mac.equals("")){
                    WifiManager wifiMan = (WifiManager) activity.getSystemService(Context.WIFI_SERVICE);
                    mac = MobileAccess.recupAdresseMAC(wifiMan);
                    if(mac != null && !mac.equals("")){
                        SharedPreferences.Editor editor = activity.getSharedPreferences("MAC_ADDRESS", Context.MODE_PRIVATE).edit();
                        editor.putString("MAC_ADDRESS", mac).commit();
                    }
                }

Answer 3

You can get the MAC address from the IPv6 local address. E.g., the IPv6 address "fe80::1034:56ff:fe78:9abc" corresponds to the MAC address "12-34-56-78-9a-bc". See the code below. Getting the WiFi IPv6 address only requires android.permission.INTERNET.

See the Wikipedia page IPv6 address, particularly the note about "local addresses" fe80::/64 and the section about "Modified EUI-64".

/**
 * Gets an EUI-48 MAC address from an IPv6 link-local address.
 * E.g., the IPv6 address "fe80::1034:56ff:fe78:9abc"
 * corresponds to the MAC address "12-34-56-78-9a-bc".
 * <p/>
 * See the note about "local addresses" fe80::/64 and the section about "Modified EUI-64" in
 * the Wikipedia article "IPv6 address" at https://en.wikipedia.org/wiki/IPv6_address
 *
 * @param ipv6 An Inet6Address object.
 * @return The EUI-48 MAC address as a byte array, null on error.
 */
private static byte[] getMacAddressFromIpv6(final Inet6Address ipv6)
{
    byte[] eui48mac = null;

    if (ipv6 != null) {
        /*
         * Make sure that this is an fe80::/64 link-local address.
         */
        final byte[] ipv6Bytes = ipv6.getAddress();
        if ((ipv6Bytes != null) &&
                (ipv6Bytes.length == 16) &&
                (ipv6Bytes[0] == (byte) 0xfe) &&
                (ipv6Bytes[1] == (byte) 0x80) &&
                (ipv6Bytes[11] == (byte) 0xff) &&
                (ipv6Bytes[12] == (byte) 0xfe)) {
            /*
             * Allocate a byte array for storing the EUI-48 MAC address, then fill it
             * from the appropriate bytes of the IPv6 address. Invert the 7th bit
             * of the first byte and discard the "ff:fe" portion of the modified
             * EUI-64 MAC address.
             */
            eui48mac = new byte[6];
            eui48mac[0] = (byte) (ipv6Bytes[8] ^ 0x2);
            eui48mac[1] = ipv6Bytes[9];
            eui48mac[2] = ipv6Bytes[10];
            eui48mac[3] = ipv6Bytes[13];
            eui48mac[4] = ipv6Bytes[14];
            eui48mac[5] = ipv6Bytes[15];
        }
    }

    return eui48mac;
}

Answer 4

Its Perfectly Fine

package com.keshav.fetchmacaddress;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;

import java.net.InetAddress;
import java.net.NetworkInterface;
import java.net.SocketException;
import java.net.UnknownHostException;
import java.util.Collections;
import java.util.List;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        Log.e("keshav","getMacAddr -> " +getMacAddr());
    }

    public static String getMacAddr() {
        try {
            List<NetworkInterface> all = Collections.list(NetworkInterface.getNetworkInterfaces());
            for (NetworkInterface nif : all) {
                if (!nif.getName().equalsIgnoreCase("wlan0")) continue;

                byte[] macBytes = nif.getHardwareAddress();
                if (macBytes == null) {
                    return "";
                }

                StringBuilder res1 = new StringBuilder();
                for (byte b : macBytes) {
                    res1.append(Integer.toHexString(b & 0xFF) + ":");
                }

                if (res1.length() > 0) {
                    res1.deleteCharAt(res1.length() - 1);
                }
                return res1.toString();
            }
        } catch (Exception ex) {
            //handle exception
        }
        return "";
    }
}