2 // System.Net.NetworkInformation.Ping
5 // Gonzalo Paniagua Javier (gonzalo@novell.com)
6 // Atsushi Enomoto (atsushi@ximian.com)
8 // Copyright (c) 2006-2007 Novell, Inc. (http://www.novell.com)
10 // Permission is hereby granted, free of charge, to any person obtaining
11 // a copy of this software and associated documentation files (the
12 // "Software"), to deal in the Software without restriction, including
13 // without limitation the rights to use, copy, modify, merge, publish,
14 // distribute, sublicense, and/or sell copies of the Software, and to
15 // permit persons to whom the Software is furnished to do so, subject to
16 // the following conditions:
18 // The above copyright notice and this permission notice shall be
19 // included in all copies or substantial portions of the Software.
21 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
22 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
23 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
24 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
25 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
26 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
27 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
32 using System.Diagnostics;
33 using System.Globalization;
34 using System.ComponentModel;
35 using System.Net.Sockets;
36 using System.Security.Principal;
37 using System.Security.Cryptography;
38 using System.Runtime.InteropServices;
40 using System.Threading;
41 using System.Threading.Tasks;
44 namespace System.Net.NetworkInformation {
45 [MonoTODO ("IPv6 support is missing")]
46 public class Ping : Component, IDisposable
48 [StructLayout(LayoutKind.Sequential)]
49 struct cap_user_header_t
51 public UInt32 version;
55 [StructLayout(LayoutKind.Sequential)]
56 struct cap_user_data_t
58 public UInt32 effective;
59 public UInt32 permitted;
60 public UInt32 inheritable;
63 const int DefaultCount = 1;
64 static readonly string [] PingBinPaths = new string [] {
72 static readonly string PingBinPath;
73 const int default_timeout = 4000; // 4 sec.
76 // This value is correct as of Linux kernel version 2.6.25.9
77 // See /usr/include/linux/capability.h
78 const UInt32 linux_cap_version = 0x20071026;
80 static readonly byte [] default_buffer = new byte [0];
81 static bool canSendPrivileged;
84 BackgroundWorker worker;
85 object user_async_state;
87 CancellationTokenSource cts;
90 public event PingCompletedEventHandler PingCompleted;
94 if (Environment.OSVersion.Platform == PlatformID.Unix) {
95 CheckLinuxCapabilities ();
96 if (!canSendPrivileged && WindowsIdentity.GetCurrent ().Name == "root")
97 canSendPrivileged = true;
99 // Since different Unix systems can have different path to bin, we try some
100 // of the known ones.
101 foreach (string ping_path in PingBinPaths)
102 if (File.Exists (ping_path)) {
103 PingBinPath = ping_path;
108 canSendPrivileged = true;
110 if (PingBinPath == null)
111 PingBinPath = "/bin/ping"; // default, fallback value
116 // Generate a new random 16 bit identifier for every ping
117 RNGCryptoServiceProvider rng = new RNGCryptoServiceProvider ();
118 byte [] randomIdentifier = new byte [2];
119 rng.GetBytes (randomIdentifier);
120 identifier = (ushort)(randomIdentifier [0] + (randomIdentifier [1] << 8));
123 [DllImport ("libc", EntryPoint="capget")]
124 static extern int capget (ref cap_user_header_t header, ref cap_user_data_t data);
126 static void CheckLinuxCapabilities ()
129 cap_user_header_t header = new cap_user_header_t ();
130 cap_user_data_t data = new cap_user_data_t ();
132 header.version = linux_cap_version;
137 ret = capget (ref header, ref data);
138 } catch (Exception) {
144 canSendPrivileged = (data.effective & (1 << 13)) != 0;
146 canSendPrivileged = false;
150 void IDisposable.Dispose ()
154 protected void OnPingCompleted (PingCompletedEventArgs e)
156 user_async_state = null;
162 if (PingCompleted != null)
163 PingCompleted (this, e);
168 public PingReply Send (IPAddress address)
170 return Send (address, default_timeout);
173 public PingReply Send (IPAddress address, int timeout)
175 return Send (address, timeout, default_buffer);
178 public PingReply Send (IPAddress address, int timeout, byte [] buffer)
180 return Send (address, timeout, buffer, new PingOptions ());
183 public PingReply Send (string hostNameOrAddress)
185 return Send (hostNameOrAddress, default_timeout);
188 public PingReply Send (string hostNameOrAddress, int timeout)
190 return Send (hostNameOrAddress, timeout, default_buffer);
193 public PingReply Send (string hostNameOrAddress, int timeout, byte [] buffer)
195 return Send (hostNameOrAddress, timeout, buffer, new PingOptions ());
198 public PingReply Send (string hostNameOrAddress, int timeout, byte [] buffer, PingOptions options)
200 IPAddress [] addresses = Dns.GetHostAddresses (hostNameOrAddress);
201 return Send (addresses [0], timeout, buffer, options);
204 static IPAddress GetNonLoopbackIP ()
206 foreach (IPAddress addr in Dns.GetHostByName (Dns.GetHostName ()).AddressList)
207 if (!IPAddress.IsLoopback (addr))
209 throw new InvalidOperationException ("Could not resolve non-loopback IP address for localhost");
212 public PingReply Send (IPAddress address, int timeout, byte [] buffer, PingOptions options)
215 throw new ArgumentNullException ("address");
217 throw new ArgumentOutOfRangeException ("timeout", "timeout must be non-negative integer");
219 throw new ArgumentNullException ("buffer");
220 if (buffer.Length > 65500)
221 throw new ArgumentException ("buffer");
222 // options can be null.
224 if (canSendPrivileged)
225 return SendPrivileged (address, timeout, buffer, options);
226 return SendUnprivileged (address, timeout, buffer, options);
229 private PingReply SendPrivileged (IPAddress address, int timeout, byte [] buffer, PingOptions options)
231 IPEndPoint target = new IPEndPoint (address, 0);
232 IPEndPoint client = new IPEndPoint (GetNonLoopbackIP (), 0);
234 // FIXME: support IPv6
235 using (Socket s = new Socket (AddressFamily.InterNetwork, SocketType.Raw, ProtocolType.Icmp)) {
236 if (options != null) {
237 s.DontFragment = options.DontFragment;
238 s.Ttl = (short) options.Ttl;
240 s.SendTimeout = timeout;
241 s.ReceiveTimeout = timeout;
242 // not sure why Identifier = 0 is unacceptable ...
243 IcmpMessage send = new IcmpMessage (8, 0, identifier, 0, buffer);
244 byte [] bytes = send.GetBytes ();
245 s.SendBufferSize = bytes.Length;
246 s.SendTo (bytes, bytes.Length, SocketFlags.None, target);
248 DateTime sentTime = DateTime.Now;
251 bytes = new byte [100];
253 EndPoint endpoint = client;
255 int rc = s.ReceiveFrom_nochecks_exc (bytes, 0, 100, SocketFlags.None,
256 ref endpoint, false, out error);
259 if (error == (int) SocketError.TimedOut) {
260 return new PingReply (null, new byte [0], options, 0, IPStatus.TimedOut);
262 throw new NotSupportedException (String.Format ("Unexpected socket error during ping request: {0}", error));
264 long rtt = (long) (DateTime.Now - sentTime).TotalMilliseconds;
265 int headerLength = (bytes [0] & 0xF) << 2;
266 int bodyLength = rc - headerLength;
268 // Ping reply to different request. discard it.
269 if (!((IPEndPoint) endpoint).Address.Equals (target.Address)) {
270 long t = timeout - rtt;
272 return new PingReply (null, new byte [0], options, 0, IPStatus.TimedOut);
273 s.ReceiveTimeout = (int) t;
277 IcmpMessage recv = new IcmpMessage (bytes, headerLength, bodyLength);
279 /* discard ping reply to different request or echo requests if running on same host. */
280 if (recv.Identifier != identifier || recv.Type == 8) {
281 long t = timeout - rtt;
283 return new PingReply (null, new byte [0], options, 0, IPStatus.TimedOut);
284 s.ReceiveTimeout = (int) t;
288 return new PingReply (address, recv.Data, options, rtt, recv.IPStatus);
293 private PingReply SendUnprivileged (IPAddress address, int timeout, byte [] buffer, PingOptions options)
295 DateTime sentTime = DateTime.Now;
297 Process ping = new Process ();
298 string args = BuildPingArgs (address, timeout, options);
301 ping.StartInfo.FileName = PingBinPath;
302 ping.StartInfo.Arguments = args;
304 ping.StartInfo.CreateNoWindow = true;
305 ping.StartInfo.UseShellExecute = false;
307 ping.StartInfo.RedirectStandardOutput = true;
308 ping.StartInfo.RedirectStandardError = true;
313 #pragma warning disable 219
314 string stdout = ping.StandardOutput.ReadToEnd ();
315 string stderr = ping.StandardError.ReadToEnd ();
316 #pragma warning restore 219
318 trip_time = (long) (DateTime.Now - sentTime).TotalMilliseconds;
319 if (!ping.WaitForExit (timeout) || (ping.HasExited && ping.ExitCode == 2))
320 return new PingReply (address, buffer, options, trip_time, IPStatus.TimedOut);
322 if (ping.ExitCode == 1)
323 return new PingReply (address, buffer, options, trip_time, IPStatus.TtlExpired);
324 } catch (Exception) {
325 return new PingReply (address, buffer, options, trip_time, IPStatus.Unknown);
334 return new PingReply (address, buffer, options, trip_time, IPStatus.Success);
339 public void SendAsync (IPAddress address, int timeout, byte [] buffer, object userToken)
341 SendAsync (address, default_timeout, default_buffer, new PingOptions (), userToken);
344 public void SendAsync (IPAddress address, int timeout, object userToken)
346 SendAsync (address, default_timeout, default_buffer, userToken);
349 public void SendAsync (IPAddress address, object userToken)
351 SendAsync (address, default_timeout, userToken);
354 public void SendAsync (string hostNameOrAddress, int timeout, byte [] buffer, object userToken)
356 SendAsync (hostNameOrAddress, timeout, buffer, new PingOptions (), userToken);
359 public void SendAsync (string hostNameOrAddress, int timeout, byte [] buffer, PingOptions options, object userToken)
361 IPAddress address = Dns.GetHostEntry (hostNameOrAddress).AddressList [0];
362 SendAsync (address, timeout, buffer, options, userToken);
365 public void SendAsync (string hostNameOrAddress, int timeout, object userToken)
367 SendAsync (hostNameOrAddress, timeout, default_buffer, userToken);
370 public void SendAsync (string hostNameOrAddress, object userToken)
372 SendAsync (hostNameOrAddress, default_timeout, userToken);
375 public void SendAsync (IPAddress address, int timeout, byte [] buffer, PingOptions options, object userToken)
378 if ((worker != null) || (cts != null))
379 throw new InvalidOperationException ("Another SendAsync operation is in progress");
382 throw new InvalidOperationException ("Another SendAsync operation is in progress");
385 worker = new BackgroundWorker ();
386 worker.DoWork += delegate (object o, DoWorkEventArgs ea) {
388 user_async_state = ea.Argument;
389 ea.Result = Send (address, timeout, buffer, options);
390 } catch (Exception ex) {
394 worker.WorkerSupportsCancellation = true;
395 worker.RunWorkerCompleted += delegate (object o, RunWorkerCompletedEventArgs ea) {
396 // Note that RunWorkerCompletedEventArgs.UserState cannot be used (LAMESPEC)
397 OnPingCompleted (new PingCompletedEventArgs (ea.Error, ea.Cancelled, user_async_state, ea.Result as PingReply));
399 worker.RunWorkerAsync (userToken);
404 public void SendAsyncCancel ()
414 throw new InvalidOperationException ("SendAsync operation is not in progress");
415 worker.CancelAsync ();
425 public IcmpMessage (byte [] bytes, int offset, int size)
427 this.bytes = new byte [size];
428 Buffer.BlockCopy (bytes, offset, this.bytes, 0, size);
432 public IcmpMessage (byte type, byte code, ushort identifier, ushort sequence, byte [] data)
434 bytes = new byte [data.Length + 8];
437 bytes [4] = (byte) (identifier & 0xFF);
438 bytes [5] = (byte) ((int) identifier >> 8);
439 bytes [6] = (byte) (sequence & 0xFF);
440 bytes [7] = (byte) ((int) sequence >> 8);
441 Buffer.BlockCopy (data, 0, bytes, 8, data.Length);
443 ushort checksum = ComputeChecksum (bytes);
444 bytes [2] = (byte) (checksum & 0xFF);
445 bytes [3] = (byte) ((int) checksum >> 8);
449 get { return bytes [0]; }
453 get { return bytes [1]; }
456 public ushort Identifier {
457 get { return (ushort) (bytes [4] + (bytes [5] << 8)); }
460 public ushort Sequence {
461 get { return (ushort) (bytes [6] + (bytes [7] << 8)); }
464 public byte [] Data {
466 byte [] data = new byte [bytes.Length - 8];
467 Buffer.BlockCopy (bytes, 8, data, 0, data.Length);
472 public byte [] GetBytes ()
477 static ushort ComputeChecksum (byte [] data)
480 for (int i = 0; i < data.Length; i += 2) {
481 ushort us = i + 1 < data.Length ? data [i + 1] : (byte) 0;
486 ret = (ret >> 16) + (ret & 0xFFFF);
487 return (ushort) ~ ret;
490 public IPStatus IPStatus {
494 return IPStatus.Success;
495 case 3: // destination unreacheable
498 return IPStatus.DestinationNetworkUnreachable;
500 return IPStatus.DestinationHostUnreachable;
502 return IPStatus.DestinationProtocolUnreachable;
504 return IPStatus.DestinationPortUnreachable;
506 return IPStatus.BadOption; // FIXME: likely wrong
508 return IPStatus.BadRoute; // not sure if it is correct
514 return IPStatus.TimeExceeded;
516 return IPStatus.TtlReassemblyTimeExceeded;
520 return IPStatus.ParameterProblem;
522 return IPStatus.SourceQuench;
524 return IPStatus.Success;
526 return IPStatus.Unknown;
527 //throw new NotSupportedException (String.Format ("Unexpected pair of ICMP message type and code: type is {0} and code is {1}", Type, Code));
532 private string BuildPingArgs (IPAddress address, int timeout, PingOptions options)
534 CultureInfo culture = CultureInfo.InvariantCulture;
535 StringBuilder args = new StringBuilder ();
536 uint t = Convert.ToUInt32 (Math.Floor ((timeout + 1000) / 1000.0));
537 bool is_mac = ((int) Environment.OSVersion.Platform == 6);
539 args.AppendFormat (culture, "-q -n -c {0} -w {1} -t {2} -M ", DefaultCount, t, options.Ttl);
541 args.AppendFormat (culture, "-q -n -c {0} -t {1} -o -m {2} ", DefaultCount, t, options.Ttl);
543 args.Append (options.DontFragment ? "do " : "dont ");
544 else if (options.DontFragment)
547 args.Append (address.ToString ());
549 return args.ToString ();
553 public Task<PingReply> SendPingAsync (IPAddress address, int timeout, byte [] buffer)
555 return SendPingAsync (address, default_timeout, default_buffer, new PingOptions ());
558 public Task<PingReply> SendPingAsync (IPAddress address, int timeout)
560 return SendPingAsync (address, default_timeout, default_buffer);
563 public Task<PingReply> SendPingAsync (IPAddress address)
565 return SendPingAsync (address, default_timeout);
568 public Task<PingReply> SendPingAsync (string hostNameOrAddress, int timeout, byte [] buffer)
570 return SendPingAsync (hostNameOrAddress, timeout, buffer, new PingOptions ());
573 public Task<PingReply> SendPingAsync (string hostNameOrAddress, int timeout, byte [] buffer, PingOptions options)
575 IPAddress address = Dns.GetHostEntry (hostNameOrAddress).AddressList [0];
576 return SendPingAsync (address, timeout, buffer, options);
579 public Task<PingReply> SendPingAsync (string hostNameOrAddress, int timeout)
581 return SendPingAsync (hostNameOrAddress, timeout, default_buffer);
584 public Task<PingReply> SendPingAsync (string hostNameOrAddress)
586 return SendPingAsync (hostNameOrAddress, default_timeout);
589 public Task<PingReply> SendPingAsync (IPAddress address, int timeout, byte [] buffer, PingOptions options)
591 if ((worker != null) || (cts != null))
592 throw new InvalidOperationException ("Another SendAsync operation is in progress");
594 var task = Task<PingReply>.Factory.StartNew (
595 () => Send (address, timeout, buffer, options), cts.Token);
597 task.ContinueWith ((t) => {
599 OnPingCompleted (new PingCompletedEventArgs (null, true, null, null));
600 else if (t.IsFaulted)
601 OnPingCompleted (new PingCompletedEventArgs (t.Exception, false, null, null));
603 OnPingCompleted (new PingCompletedEventArgs (null, false, null, t.Result));