/// <summary>
/// This tries to lookup the MAC address that corresponds to an IP address using a way supported on the current platform. Windows and Linux are supported.
/// On Windows an API call to IpHlpApi.SendARP is used.
/// On Linux the /proc/net/arp file, which contains systems the arp cache is read. If the IP address is found there the corresponding MAC address is returned directly.
/// Otherwise, an ICMP ping is sent to the given IP address and the arp cache lookup is repeated afterwards. This implementation uses synchronous code.
/// </summary>
/// <param name="ip">The IP address to look the mac address up for.</param>
/// <returns>The mac address if found, null otherwise.</returns>
public static PhysicalAddress?Lookup(IPAddress ip)
{
if (WindowsLookupService.IsSupported)
{
return(WindowsLookupService.Lookup(ip));
}
if (LinuxLookupService.IsSupported)
{
var mac = LinuxLookupService.TryReadFromArpTable(ip);
if (mac != null)
{
return(mac);
}
return(LinuxLookupService.PingThenTryReadFromArpTable(ip, LinuxPingTimeout));
}
throw new PlatformNotSupportedException();
}
/// <summary>
/// This tries to lookup the MAC address that corresponds to an IP address using a way supported on the current platform. Windows and Linux are supported.
/// On Windows an API call to IpHlpApi.SendARP is used. Beware that this implementation is not truly async but just returns a finished task containing the result.
/// On Linux the /proc/net/arp file, which contains systems the arp cache is read. If the IP address is found there the corresponding MAC address is returned directly.
/// Otherwise, an ICMP ping is sent to the given IP address and the arp cache lookup is repeated afterwards. This implementation uses async file IO and the framework's async ping implementation.
/// </summary>
/// <param name="ip">The IP address to look the mac address up for.</param>
/// <returns>The mac address if found, null otherwise.</returns>
public static async Task <PhysicalAddress?> LookupAsync(IPAddress ip)
{
if (WindowsLookupService.IsSupported)
{
return(WindowsLookupService.Lookup(ip));
}
if (LinuxLookupService.IsSupported)
{
var mac = await LinuxLookupService.TryReadFromArpTableAsync(ip).ConfigureAwait(false);
if (mac != null)
{
return(mac);
}
return(await LinuxLookupService.PingThenTryReadFromArpTableAsync(ip, LinuxPingTimeout).ConfigureAwait(false));
}
throw new PlatformNotSupportedException();
}