Is there any way to get a the list of connected MAC addresses when my phone is on Wi-Fi tethering mode?
Reading /proc/net/arp
would provide the information for both static and DHCP clients that have communicated with the device during the last 60 seconds (configured in /proc/sys/net/ipv4/neigh/wl0.1/gc_stale_time
where wl0.1
is the wireless network interface on my phone).
It is available for non-root users too.
@SuppressWarnings("ConstantConditions")
public static String getClientMacByIP(String ip)
{
String res = "";
if (ip == null)
return res;
String flushCmd = "sh ip -s -s neigh flush all";
Runtime runtime = Runtime.getRuntime();
try
{
runtime.exec(flushCmd,null,new File("/proc/net"));
}
BufferedReader br;
try
{
br = new BufferedReader(new FileReader("/proc/net/arp"));
String line;
while ((line = br.readLine()) != null)
{
String[] sp = line.split(" +");
if (sp.length >= 4 && ip.equals(sp[0]))
{Assistance.Log(sp[0]+sp[2]+sp[3],ALERT_STATES.ALERT_STATE_LOG);
String mac = sp[3];
if (mac.matches("..:..:..:..:..:..") && sp[2].equals("0x2"))
{
res = mac;
break;
}
}
}
br.close();
}
catch (Exception e)
{}
return res;
}
//--------------------------------------------------------
@SuppressWarnings("ConstantConditions")
public static String getClientIPByMac(String mac)
{
String res = "";
if (mac == null)
return res;
String flushCmd = "sh ip -s -s neigh flush all";
Runtime runtime = Runtime.getRuntime();
try
{
runtime.exec(flushCmd,null,new File("/proc/net"));
}
BufferedReader br;
try
{
br = new BufferedReader(new FileReader("/proc/net/arp"));
String line;
while ((line = br.readLine()) != null)
{
String[] sp = line.split(" +");
if (sp.length >= 4 && mac.equals(sp[3]))
{
String ip = sp[0];
if (ip.matches("\\d{1,3}\\.\\d{1,3}\\.\\d{1,3}\\.\\d{1,3}") && sp[2].equals("0x2"))
{
res = ip;
break;
}
}
}
br.close();
}
catch (Exception e)
{}
return res;
}
public static ArrayList<String> getConnectedDevicesMac()
{
ArrayList<String> res = new ArrayList<String>();
//NetManager.updateArpFile();
BufferedReader br;
try
{
br = new BufferedReader(new FileReader("/proc/net/arp"));
String line;
line = br.readLine();
while ((line = br.readLine()) != null)
{
String[] sp = line.split(" +");
if (sp[3].matches("..:..:..:..:..:.."))
res.add(sp[3]);
}
br.close();
}
catch (Exception e)
{}
return res;
}
Firstly, you must have a rooted device. When it's done just read dnsmasq.leases file. Usually it is placed at: /data/misc/dhcp/dnsmasq.leases. A structure of the file is pretty simple - each line is a summary of a connected user. The summary has several fields including MAC. I didn't find a possibility to get MAC without root. Please correct me if I'm wrong.