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)
9 // Copyright 2015 Xamarin Inc.
11 // Permission is hereby granted, free of charge, to any person obtaining
12 // a copy of this software and associated documentation files (the
13 // "Software"), to deal in the Software without restriction, including
14 // without limitation the rights to use, copy, modify, merge, publish,
15 // distribute, sublicense, and/or sell copies of the Software, and to
16 // permit persons to whom the Software is furnished to do so, subject to
17 // the following conditions:
19 // The above copyright notice and this permission notice shall be
20 // included in all copies or substantial portions of the Software.
22 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
23 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
24 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
25 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
26 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
27 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
28 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
34 using System.Diagnostics;
35 using System.Globalization;
36 using System.ComponentModel;
37 using System.Net.Sockets;
38 using System.Security.Principal;
39 using System.Security.Cryptography;
40 using System.Runtime.InteropServices;
41 using System.Threading;
42 using System.Threading.Tasks;
44 namespace System.Net.NetworkInformation {
45 [MonoTODO ("IPv6 support is missing")]
46 public class Ping : Component, IDisposable
49 [StructLayout(LayoutKind.Sequential)]
50 struct cap_user_header_t
52 public UInt32 version;
56 [StructLayout(LayoutKind.Sequential)]
57 struct cap_user_data_t
59 public UInt32 effective;
60 public UInt32 permitted;
61 public UInt32 inheritable;
64 const int DefaultCount = 1;
65 static readonly string [] PingBinPaths = new string [] {
73 static readonly string PingBinPath;
75 const int default_timeout = 4000; // 4 sec.
78 // This value is correct as of Linux kernel version 2.6.25.9
79 // See /usr/include/linux/capability.h
80 const UInt32 linux_cap_version = 0x20071026;
82 static readonly byte [] default_buffer = new byte [0];
83 static bool canSendPrivileged;
86 BackgroundWorker worker;
87 object user_async_state;
88 CancellationTokenSource cts;
90 public event PingCompletedEventHandler PingCompleted;
95 if (Environment.OSVersion.Platform == PlatformID.Unix) {
96 CheckLinuxCapabilities ();
97 if (!canSendPrivileged && WindowsIdentity.GetCurrent ().Name == "root")
98 canSendPrivileged = true;
100 // Since different Unix systems can have different path to bin, we try some
101 // of the known ones.
102 foreach (string ping_path in PingBinPaths)
103 if (File.Exists (ping_path)) {
104 PingBinPath = ping_path;
109 canSendPrivileged = true;
111 if (PingBinPath == null)
112 PingBinPath = "/bin/ping"; // default, fallback value
118 // Generate a new random 16 bit identifier for every ping
119 RNGCryptoServiceProvider rng = new RNGCryptoServiceProvider ();
120 byte [] randomIdentifier = new byte [2];
121 rng.GetBytes (randomIdentifier);
122 identifier = (ushort)(randomIdentifier [0] + (randomIdentifier [1] << 8));
126 [DllImport ("libc", EntryPoint="capget")]
127 static extern int capget (ref cap_user_header_t header, ref cap_user_data_t data);
129 static void CheckLinuxCapabilities ()
132 cap_user_header_t header = new cap_user_header_t ();
133 cap_user_data_t data = new cap_user_data_t ();
135 header.version = linux_cap_version;
140 ret = capget (ref header, ref data);
141 } catch (Exception) {
147 canSendPrivileged = (data.effective & (1 << 13)) != 0;
149 canSendPrivileged = false;
154 void IDisposable.Dispose ()
158 protected void OnPingCompleted (PingCompletedEventArgs e)
160 user_async_state = null;
164 if (PingCompleted != null)
165 PingCompleted (this, e);
170 public PingReply Send (IPAddress address)
172 return Send (address, default_timeout);
175 public PingReply Send (IPAddress address, int timeout)
177 return Send (address, timeout, default_buffer);
180 public PingReply Send (IPAddress address, int timeout, byte [] buffer)
182 return Send (address, timeout, buffer, new PingOptions ());
185 public PingReply Send (string hostNameOrAddress)
187 return Send (hostNameOrAddress, default_timeout);
190 public PingReply Send (string hostNameOrAddress, int timeout)
192 return Send (hostNameOrAddress, timeout, default_buffer);
195 public PingReply Send (string hostNameOrAddress, int timeout, byte [] buffer)
197 return Send (hostNameOrAddress, timeout, buffer, new PingOptions ());
200 public PingReply Send (string hostNameOrAddress, int timeout, byte [] buffer, PingOptions options)
202 IPAddress [] addresses = Dns.GetHostAddresses (hostNameOrAddress);
203 return Send (addresses [0], timeout, buffer, options);
206 static IPAddress GetNonLoopbackIP ()
208 foreach (IPAddress addr in Dns.GetHostByName (Dns.GetHostName ()).AddressList)
209 if (!IPAddress.IsLoopback (addr))
211 throw new InvalidOperationException ("Could not resolve non-loopback IP address for localhost");
214 public PingReply Send (IPAddress address, int timeout, byte [] buffer, PingOptions options)
217 throw new ArgumentNullException ("address");
219 throw new ArgumentOutOfRangeException ("timeout", "timeout must be non-negative integer");
221 throw new ArgumentNullException ("buffer");
222 if (buffer.Length > 65500)
223 throw new ArgumentException ("buffer");
224 // options can be null.
227 throw new InvalidOperationException ();
229 if (canSendPrivileged)
230 return SendPrivileged (address, timeout, buffer, options);
231 return SendUnprivileged (address, timeout, buffer, options);
236 private PingReply SendPrivileged (IPAddress address, int timeout, byte [] buffer, PingOptions options)
238 IPEndPoint target = new IPEndPoint (address, 0);
239 IPEndPoint client = new IPEndPoint (GetNonLoopbackIP (), 0);
241 // FIXME: support IPv6
242 using (Socket s = new Socket (AddressFamily.InterNetwork, SocketType.Raw, ProtocolType.Icmp)) {
243 if (options != null) {
244 s.DontFragment = options.DontFragment;
245 s.Ttl = (short) options.Ttl;
247 s.SendTimeout = timeout;
248 s.ReceiveTimeout = timeout;
249 // not sure why Identifier = 0 is unacceptable ...
250 IcmpMessage send = new IcmpMessage (8, 0, identifier, 0, buffer);
251 byte [] bytes = send.GetBytes ();
252 s.SendBufferSize = bytes.Length;
253 s.SendTo (bytes, bytes.Length, SocketFlags.None, target);
255 DateTime sentTime = DateTime.Now;
258 bytes = new byte [100];
260 EndPoint endpoint = client;
262 int rc = s.ReceiveFrom_nochecks_exc (bytes, 0, 100, SocketFlags.None,
263 ref endpoint, false, out error);
266 if (error == (int) SocketError.TimedOut) {
267 return new PingReply (null, new byte [0], options, 0, IPStatus.TimedOut);
269 throw new NotSupportedException (String.Format ("Unexpected socket error during ping request: {0}", error));
271 long rtt = (long) (DateTime.Now - sentTime).TotalMilliseconds;
272 int headerLength = (bytes [0] & 0xF) << 2;
273 int bodyLength = rc - headerLength;
275 // Ping reply to different request. discard it.
276 if (!((IPEndPoint) endpoint).Address.Equals (target.Address)) {
277 long t = timeout - rtt;
279 return new PingReply (null, new byte [0], options, 0, IPStatus.TimedOut);
280 s.ReceiveTimeout = (int) t;
284 IcmpMessage recv = new IcmpMessage (bytes, headerLength, bodyLength);
286 /* discard ping reply to different request or echo requests if running on same host. */
287 if (recv.Identifier != identifier || recv.Type == 8) {
288 long t = timeout - rtt;
290 return new PingReply (null, new byte [0], options, 0, IPStatus.TimedOut);
291 s.ReceiveTimeout = (int) t;
295 return new PingReply (address, recv.Data, options, rtt, recv.IPStatus);
300 private PingReply SendUnprivileged (IPAddress address, int timeout, byte [] buffer, PingOptions options)
302 #if MONO_FEATURE_PROCESS_START
303 DateTime sentTime = DateTime.UtcNow;
305 Process ping = new Process ();
306 string args = BuildPingArgs (address, timeout, options);
309 ping.StartInfo.FileName = PingBinPath;
310 ping.StartInfo.Arguments = args;
312 ping.StartInfo.CreateNoWindow = true;
313 ping.StartInfo.UseShellExecute = false;
315 ping.StartInfo.RedirectStandardOutput = true;
316 ping.StartInfo.RedirectStandardError = true;
318 IPStatus status = IPStatus.Unknown;
322 #pragma warning disable 219
323 string stdout = ping.StandardOutput.ReadToEnd ();
324 string stderr = ping.StandardError.ReadToEnd ();
325 #pragma warning restore 219
327 trip_time = (long) (DateTime.UtcNow - sentTime).TotalMilliseconds;
328 if (!ping.WaitForExit (timeout) || (ping.HasExited && ping.ExitCode == 2))
329 status = IPStatus.TimedOut;
330 else if (ping.ExitCode == 0)
331 status = IPStatus.Success;
332 else if (ping.ExitCode == 1)
333 status = IPStatus.TtlExpired;
341 return new PingReply (address, buffer, options, trip_time, status);
343 throw new PlatformNotSupportedException ("Ping is not supported on this platform.");
344 #endif // MONO_FEATURE_PROCESS_START
350 public void SendAsync (IPAddress address, int timeout, byte [] buffer, object userToken)
352 SendAsync (address, default_timeout, default_buffer, new PingOptions (), userToken);
355 public void SendAsync (IPAddress address, int timeout, object userToken)
357 SendAsync (address, default_timeout, default_buffer, userToken);
360 public void SendAsync (IPAddress address, object userToken)
362 SendAsync (address, default_timeout, userToken);
365 public void SendAsync (string hostNameOrAddress, int timeout, byte [] buffer, object userToken)
367 SendAsync (hostNameOrAddress, timeout, buffer, new PingOptions (), userToken);
370 public void SendAsync (string hostNameOrAddress, int timeout, byte [] buffer, PingOptions options, object userToken)
372 IPAddress address = Dns.GetHostEntry (hostNameOrAddress).AddressList [0];
373 SendAsync (address, timeout, buffer, options, userToken);
376 public void SendAsync (string hostNameOrAddress, int timeout, object userToken)
378 SendAsync (hostNameOrAddress, timeout, default_buffer, userToken);
381 public void SendAsync (string hostNameOrAddress, object userToken)
383 SendAsync (hostNameOrAddress, default_timeout, userToken);
386 public void SendAsync (IPAddress address, int timeout, byte [] buffer, PingOptions options, object userToken)
388 if ((worker != null) || (cts != null))
389 throw new InvalidOperationException ("Another SendAsync operation is in progress");
391 worker = new BackgroundWorker ();
392 worker.DoWork += delegate (object o, DoWorkEventArgs ea) {
394 user_async_state = ea.Argument;
395 ea.Result = Send (address, timeout, buffer, options);
396 } catch (Exception ex) {
400 worker.WorkerSupportsCancellation = true;
401 worker.RunWorkerCompleted += delegate (object o, RunWorkerCompletedEventArgs ea) {
402 // Note that RunWorkerCompletedEventArgs.UserState cannot be used (LAMESPEC)
403 OnPingCompleted (new PingCompletedEventArgs (ea.Error, ea.Cancelled, user_async_state, ea.Result as PingReply));
405 worker.RunWorkerAsync (userToken);
410 public void SendAsyncCancel ()
418 throw new InvalidOperationException ("SendAsync operation is not in progress");
419 worker.CancelAsync ();
430 public IcmpMessage (byte [] bytes, int offset, int size)
432 this.bytes = new byte [size];
433 Buffer.BlockCopy (bytes, offset, this.bytes, 0, size);
437 public IcmpMessage (byte type, byte code, ushort identifier, ushort sequence, byte [] data)
439 bytes = new byte [data.Length + 8];
442 bytes [4] = (byte) (identifier & 0xFF);
443 bytes [5] = (byte) ((int) identifier >> 8);
444 bytes [6] = (byte) (sequence & 0xFF);
445 bytes [7] = (byte) ((int) sequence >> 8);
446 Buffer.BlockCopy (data, 0, bytes, 8, data.Length);
448 ushort checksum = ComputeChecksum (bytes);
449 bytes [2] = (byte) (checksum & 0xFF);
450 bytes [3] = (byte) ((int) checksum >> 8);
454 get { return bytes [0]; }
458 get { return bytes [1]; }
461 public ushort Identifier {
462 get { return (ushort) (bytes [4] + (bytes [5] << 8)); }
465 public ushort Sequence {
466 get { return (ushort) (bytes [6] + (bytes [7] << 8)); }
469 public byte [] Data {
471 byte [] data = new byte [bytes.Length - 8];
472 Buffer.BlockCopy (bytes, 8, data, 0, data.Length);
477 public byte [] GetBytes ()
482 static ushort ComputeChecksum (byte [] data)
485 for (int i = 0; i < data.Length; i += 2) {
486 ushort us = i + 1 < data.Length ? data [i + 1] : (byte) 0;
491 ret = (ret >> 16) + (ret & 0xFFFF);
492 return (ushort) ~ ret;
495 public IPStatus IPStatus {
499 return IPStatus.Success;
500 case 3: // destination unreacheable
503 return IPStatus.DestinationNetworkUnreachable;
505 return IPStatus.DestinationHostUnreachable;
507 return IPStatus.DestinationProtocolUnreachable;
509 return IPStatus.DestinationPortUnreachable;
511 return IPStatus.BadOption; // FIXME: likely wrong
513 return IPStatus.BadRoute; // not sure if it is correct
519 return IPStatus.TimeExceeded;
521 return IPStatus.TtlReassemblyTimeExceeded;
525 return IPStatus.ParameterProblem;
527 return IPStatus.SourceQuench;
529 return IPStatus.Success;
531 return IPStatus.Unknown;
532 //throw new NotSupportedException (String.Format ("Unexpected pair of ICMP message type and code: type is {0} and code is {1}", Type, Code));
537 private string BuildPingArgs (IPAddress address, int timeout, PingOptions options)
539 CultureInfo culture = CultureInfo.InvariantCulture;
540 StringBuilder args = new StringBuilder ();
541 uint t = Convert.ToUInt32 (Math.Floor ((timeout + 1000) / 1000.0));
542 bool is_mac = Platform.IsMacOS;
544 args.AppendFormat (culture, "-q -n -c {0} -w {1} -t {2} -M ", DefaultCount, t, options.Ttl);
546 args.AppendFormat (culture, "-q -n -c {0} -t {1} -o -m {2} ", DefaultCount, t, options.Ttl);
548 args.Append (options.DontFragment ? "do " : "dont ");
549 else if (options.DontFragment)
552 args.Append (address.ToString ());
554 return args.ToString ();
558 public Task<PingReply> SendPingAsync (IPAddress address, int timeout, byte [] buffer)
560 return SendPingAsync (address, default_timeout, default_buffer, new PingOptions ());
563 public Task<PingReply> SendPingAsync (IPAddress address, int timeout)
565 return SendPingAsync (address, default_timeout, default_buffer);
568 public Task<PingReply> SendPingAsync (IPAddress address)
570 return SendPingAsync (address, default_timeout);
573 public Task<PingReply> SendPingAsync (string hostNameOrAddress, int timeout, byte [] buffer)
575 return SendPingAsync (hostNameOrAddress, timeout, buffer, new PingOptions ());
578 public Task<PingReply> SendPingAsync (string hostNameOrAddress, int timeout, byte [] buffer, PingOptions options)
580 IPAddress address = Dns.GetHostEntry (hostNameOrAddress).AddressList [0];
581 return SendPingAsync (address, timeout, buffer, options);
584 public Task<PingReply> SendPingAsync (string hostNameOrAddress, int timeout)
586 return SendPingAsync (hostNameOrAddress, timeout, default_buffer);
589 public Task<PingReply> SendPingAsync (string hostNameOrAddress)
591 return SendPingAsync (hostNameOrAddress, default_timeout);
594 public Task<PingReply> SendPingAsync (IPAddress address, int timeout, byte [] buffer, PingOptions options)
596 if ((worker != null) || (cts != null))
597 throw new InvalidOperationException ("Another SendAsync operation is in progress");
599 var task = Task<PingReply>.Factory.StartNew (
600 () => Send (address, timeout, buffer, options), cts.Token);
602 task.ContinueWith ((t) => {
604 OnPingCompleted (new PingCompletedEventArgs (null, true, null, null));
605 else if (t.IsFaulted)
606 OnPingCompleted (new PingCompletedEventArgs (t.Exception, false, null, null));
608 OnPingCompleted (new PingCompletedEventArgs (null, false, null, t.Result));