mcs/class/System/System.Net/Dns.cs

   1 // System.Net.Dns.cs
   2 //
   3 // Authors:
   4 //      Mads Pultz (mpultz@diku.dk)
   5 //      Lawrence Pit (loz@cable.a2000.nl)
   6
   7 // Author: Mads Pultz (mpultz@diku.dk)
   8 //         Lawrence Pit (loz@cable.a2000.nl)
   9 //         Marek Safar (marek.safar@gmail.com)
  10 //         Gonzalo Paniagua Javier (gonzalo.mono@gmail.com)
  11 //
  12 // (C) Mads Pultz, 2001
  13 // Copyright (c) 2011 Novell, Inc.
  14 // Copyright (c) 2011 Xamarin, Inc.
  15
  16 //
  17 // Permission is hereby granted, free of charge, to any person obtaining
  18 // a copy of this software and associated documentation files (the
  19 // "Software"), to deal in the Software without restriction, including
  20 // without limitation the rights to use, copy, modify, merge, publish,
  21 // distribute, sublicense, and/or sell copies of the Software, and to
  22 // permit persons to whom the Software is furnished to do so, subject to
  23 // the following conditions:
  24 //
  25 // The above copyright notice and this permission notice shall be
  26 // included in all copies or substantial portions of the Software.
  27 //
  28 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  29 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  30 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  31 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  32 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  33 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  34 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  35 //
  36
  37 using System;
  38 using System.Net.Sockets;
  39 using System.Text;
  40 using System.Collections;
  41 using System.Threading;
  42 using System.Runtime.CompilerServices;
  43 using System.Runtime.Remoting.Messaging;
  44 #if NET_4_5
  45 using System.Threading.Tasks;
  46 #endif
  47
  48 using Mono.Dns;
  49
  50 namespace System.Net {
  51         public static class Dns {
  52                 static bool use_mono_dns;
  53                 static SimpleResolver resolver;
  54
  55                 static Dns ()
  56                 {
  57                         System.Net.Sockets.Socket.CheckProtocolSupport();
  58                         if (Environment.GetEnvironmentVariable ("MONO_DNS") != null) {
  59                                 resolver = new SimpleResolver ();
  60                                 use_mono_dns = true;
  61                         }
  62                 }
  63
  64                 internal static bool UseMonoDns {
  65                         get { return use_mono_dns; }
  66                 }
  67
  68 #if !MOONLIGHT // global remove of async methods
  69
  70                 private delegate IPHostEntry GetHostByNameCallback (string hostName);
  71                 private delegate IPHostEntry ResolveCallback (string hostName);
  72                 private delegate IPHostEntry GetHostEntryNameCallback (string hostName);
  73                 private delegate IPHostEntry GetHostEntryIPCallback (IPAddress hostAddress);
  74                 private delegate IPAddress [] GetHostAddressesCallback (string hostName);
  75
  76                 static void OnCompleted (object sender, SimpleResolverEventArgs e)
  77                 {
  78                         DnsAsyncResult ares = (DnsAsyncResult) e.UserToken;
  79                         IPHostEntry entry = e.HostEntry;
  80                         if (entry == null || e.ResolverError != 0) {
  81                                 ares.SetCompleted (false, new Exception ("Error: " + e.ResolverError));
  82                                 return;
  83                         }
  84                         ares.SetCompleted (false, entry);
  85                 }
  86
  87                 static IAsyncResult BeginAsyncCallAddresses (string host, AsyncCallback callback, object state)
  88                 {
  89                         SimpleResolverEventArgs e = new SimpleResolverEventArgs ();
  90                         e.Completed += OnCompleted;
  91                         e.HostName = host;
  92                         DnsAsyncResult ares = new DnsAsyncResult (callback, state);
  93                         e.UserToken = ares;
  94                         if (resolver.GetHostAddressesAsync (e) == false)
  95                                 ares.SetCompleted (true, e.HostEntry); // Completed synchronously
  96                         return ares;
  97                 }
  98
  99                 static IAsyncResult BeginAsyncCall (string host, AsyncCallback callback, object state)
 100                 {
 101                         SimpleResolverEventArgs e = new SimpleResolverEventArgs ();
 102                         e.Completed += OnCompleted;
 103                         e.HostName = host;
 104                         DnsAsyncResult ares = new DnsAsyncResult (callback, state);
 105                         e.UserToken = ares;
 106                         if (resolver.GetHostEntryAsync (e) == false)
 107                                 ares.SetCompleted (true, e.HostEntry); // Completed synchronously
 108                         return ares;
 109                 }
 110
 111                 static IPHostEntry EndAsyncCall (DnsAsyncResult ares)
 112                 {
 113                         if (ares == null)
 114                                 throw new ArgumentException ("Invalid asyncResult");
 115                         if (!ares.IsCompleted)
 116                                 ares.AsyncWaitHandle.WaitOne ();
 117                         if (ares.Exception != null)
 118                                 throw ares.Exception;
 119                         IPHostEntry entry = ares.HostEntry;
 120                         if (entry == null || entry.AddressList == null || entry.AddressList.Length == 0)
 121                                 throw new SocketException(11001);
 122                         return entry;
 123                 }
 124
 125                 [Obsolete ("Use BeginGetHostEntry instead")]
 126                 public static IAsyncResult BeginGetHostByName (string hostName, AsyncCallback requestCallback, object stateObject)
 127                 {
 128                         if (hostName == null)
 129                                 throw new ArgumentNullException ("hostName");
 130
 131                         if (use_mono_dns)
 132                                 return BeginAsyncCall (hostName, requestCallback, stateObject);
 133
 134                         GetHostByNameCallback c = new GetHostByNameCallback (GetHostByName);
 135                         return c.BeginInvoke (hostName, requestCallback, stateObject);
 136                 }
 137
 138                 [Obsolete ("Use BeginGetHostEntry instead")]
 139                 public static IAsyncResult BeginResolve (string hostName, AsyncCallback requestCallback, object stateObject)
 140                 {
 141                         if (hostName == null)
 142                                 throw new ArgumentNullException ("hostName");
 143
 144                         if (use_mono_dns)
 145                                 return BeginAsyncCall (hostName, requestCallback, stateObject);
 146
 147                         ResolveCallback c = new ResolveCallback (Resolve);
 148                         return c.BeginInvoke (hostName, requestCallback, stateObject);
 149                 }
 150
 151                 public static IAsyncResult BeginGetHostAddresses (string hostNameOrAddress, AsyncCallback requestCallback, object stateObject)
 152                 {
 153                         if (hostNameOrAddress == null)
 154                                 throw new ArgumentNullException ("hostName");
 155                         if (hostNameOrAddress == "0.0.0.0" || hostNameOrAddress == "::0")
 156                                 throw new ArgumentException ("Addresses 0.0.0.0 (IPv4) " +
 157                                         "and ::0 (IPv6) are unspecified addresses. You " +
 158                                         "cannot use them as target address.",
 159                                         "hostNameOrAddress");
 160
 161                         if (use_mono_dns)
 162                                 return BeginAsyncCallAddresses (hostNameOrAddress, requestCallback, stateObject);
 163
 164                         GetHostAddressesCallback c = new GetHostAddressesCallback (GetHostAddresses);
 165                         return c.BeginInvoke (hostNameOrAddress, requestCallback, stateObject);
 166                 }
 167
 168                 public static IAsyncResult BeginGetHostEntry (string hostNameOrAddress, AsyncCallback requestCallback, object stateObject)
 169                 {
 170                         if (hostNameOrAddress == null)
 171                                 throw new ArgumentNullException ("hostName");
 172                         if (hostNameOrAddress == "0.0.0.0" || hostNameOrAddress == "::0")
 173                                 throw new ArgumentException ("Addresses 0.0.0.0 (IPv4) " +
 174                                         "and ::0 (IPv6) are unspecified addresses. You " +
 175                                         "cannot use them as target address.",
 176                                         "hostNameOrAddress");
 177
 178                         if (use_mono_dns)
 179                                 return BeginAsyncCall (hostNameOrAddress, requestCallback, stateObject);
 180
 181                         GetHostEntryNameCallback c = new GetHostEntryNameCallback (GetHostEntry);
 182                         return c.BeginInvoke (hostNameOrAddress, requestCallback, stateObject);
 183                 }
 184
 185                 public static IAsyncResult BeginGetHostEntry (IPAddress address, AsyncCallback requestCallback, object stateObject)
 186                 {
 187                         if (address == null)
 188                                 throw new ArgumentNullException ("address");
 189
 190                         if (use_mono_dns)
 191                                 return BeginAsyncCall (address.ToString (), requestCallback, stateObject);
 192
 193                         GetHostEntryIPCallback c = new GetHostEntryIPCallback (GetHostEntry);
 194                         return c.BeginInvoke (address, requestCallback, stateObject);
 195                 }
 196
 197                 [Obsolete ("Use EndGetHostEntry instead")]
 198                 public static IPHostEntry EndGetHostByName (IAsyncResult asyncResult)
 199                 {
 200                         if (asyncResult == null)
 201                                 throw new ArgumentNullException ("asyncResult");
 202
 203                         if (use_mono_dns)
 204                                 return EndAsyncCall (asyncResult as DnsAsyncResult);
 205
 206                         AsyncResult async = (AsyncResult) asyncResult;
 207                         GetHostByNameCallback cb = (GetHostByNameCallback) async.AsyncDelegate;
 208                         return cb.EndInvoke(asyncResult);
 209                 }
 210
 211                 [Obsolete ("Use EndGetHostEntry instead")]
 212                 public static IPHostEntry EndResolve (IAsyncResult asyncResult)
 213                 {
 214                         if (asyncResult == null)
 215                                 throw new ArgumentNullException ("asyncResult");
 216
 217                         if (use_mono_dns)
 218                                 return EndAsyncCall (asyncResult as DnsAsyncResult);
 219
 220                         AsyncResult async = (AsyncResult) asyncResult;
 221                         ResolveCallback cb = (ResolveCallback) async.AsyncDelegate;
 222                         return cb.EndInvoke(asyncResult);
 223                 }
 224
 225                 public static IPAddress [] EndGetHostAddresses (IAsyncResult asyncResult)
 226                 {
 227                         if (asyncResult == null)
 228                                 throw new ArgumentNullException ("asyncResult");
 229
 230                         if (use_mono_dns) {
 231                                 IPHostEntry entry = EndAsyncCall (asyncResult as DnsAsyncResult);
 232                                 if (entry == null)
 233                                         return null;
 234                                 return entry.AddressList;
 235                         }
 236
 237                         AsyncResult async = (AsyncResult) asyncResult;
 238                         GetHostAddressesCallback cb = (GetHostAddressesCallback) async.AsyncDelegate;
 239                         return cb.EndInvoke(asyncResult);
 240                 }
 241
 242                 public static IPHostEntry EndGetHostEntry (IAsyncResult asyncResult)
 243                 {
 244                         if (asyncResult == null)
 245                                 throw new ArgumentNullException ("asyncResult");
 246
 247                         if (use_mono_dns)
 248                                 return EndAsyncCall (asyncResult as DnsAsyncResult);
 249
 250                         AsyncResult async = (AsyncResult) asyncResult;
 251                         if (async.AsyncDelegate is GetHostEntryIPCallback)
 252                                 return ((GetHostEntryIPCallback) async.AsyncDelegate).EndInvoke (asyncResult);
 253                         GetHostEntryNameCallback cb = (GetHostEntryNameCallback) async.AsyncDelegate;
 254                         return cb.EndInvoke(asyncResult);
 255                 }
 256
 257 #endif // !MOONLIGHT: global remove of async methods
 258
 259 #if !TARGET_JVM
 260                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
 261                 private extern static bool GetHostByName_internal(string host, out string h_name, out string[] h_aliases, out string[] h_addr_list);
 262
 263                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
 264                 private extern static bool GetHostByAddr_internal(string addr, out string h_name, out string[] h_aliases, out string[] h_addr_list);
 265
 266                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
 267                 private extern static bool GetHostName_internal(out string h_name);
 268 #endif
 269
 270                 private static IPHostEntry hostent_to_IPHostEntry(string h_name, string[] h_aliases, string[] h_addrlist)
 271                 {
 272                         IPHostEntry he = new IPHostEntry();
 273                         ArrayList addrlist = new ArrayList();
 274
 275                         he.HostName = h_name;
 276                         he.Aliases = h_aliases;
 277                         for(int i=0; i<h_addrlist.Length; i++) {
 278                                 try {
 279                                         IPAddress newAddress = IPAddress.Parse(h_addrlist[i]);
 280
 281                                         if( (Socket.SupportsIPv6 && newAddress.AddressFamily == AddressFamily.InterNetworkV6) ||
 282                                             (Socket.SupportsIPv4 && newAddress.AddressFamily == AddressFamily.InterNetwork) )
 283                                                 addrlist.Add(newAddress);
 284                                 } catch (ArgumentNullException) {
 285                                         /* Ignore this, as the
 286                                          * internal call might have
 287                                          * left some blank entries at
 288                                          * the end of the array
 289                                          */
 290                                 }
 291                         }
 292
 293                         if(addrlist.Count == 0)
 294                                 throw new SocketException(11001);
 295
 296                         he.AddressList = addrlist.ToArray(typeof(IPAddress)) as IPAddress[];
 297                         return he;
 298                 }
 299
 300                 [Obsolete ("Use GetHostEntry instead")]
 301                 public static IPHostEntry GetHostByAddress(IPAddress address)
 302                 {
 303                         if (address == null)
 304                                 throw new ArgumentNullException ("address");
 305
 306                         return GetHostByAddressFromString (address.ToString (), false);
 307                 }
 308
 309                 [Obsolete ("Use GetHostEntry instead")]
 310                 public static IPHostEntry GetHostByAddress(string address)
 311                 {
 312                         if (address == null)
 313                                 throw new ArgumentNullException ("address");
 314
 315                         return GetHostByAddressFromString (address, true);
 316                 }
 317
 318                 static IPHostEntry GetHostByAddressFromString (string address, bool parse)
 319                 {
 320                         // Undocumented MS behavior: when called with IF_ANY,
 321                         // this should return the local host
 322                         if (address.Equals ("0.0.0.0")) {
 323                                 address = "127.0.0.1";
 324                                 parse = false;
 325                         }
 326
 327                         // Must check the IP format, might send an exception if invalid string.
 328                         if (parse)
 329                                 IPAddress.Parse (address);
 330
 331                         string h_name;
 332                         string[] h_aliases, h_addrlist;
 333 #if TARGET_JVM
 334                         h_name = null;
 335                         h_aliases = null;
 336                         h_addrlist = null;
 337                         try {
 338                                 java.net.InetAddress[] iaArr =
 339                                         java.net.InetAddress.getAllByName(address);
 340                                 if (iaArr != null && iaArr.Length > 0)
 341                                     h_name = iaArr[0].getHostName();
 342                                 if (iaArr != null && iaArr.Length > 0)
 343                                 {
 344                                     h_addrlist = new String[iaArr.Length];
 345                                     for (int i = 0; i < h_addrlist.Length; i++)
 346                                         h_addrlist[i] = iaArr[i].getHostAddress();
 347                                 }
 348                         } catch (java.net.UnknownHostException jUHE) {
 349                                 throw new SocketException((int)SocketError.HostNotFound, jUHE.Message);
 350                         }
 351 #else
 352                         bool ret = GetHostByAddr_internal(address, out h_name, out h_aliases, out h_addrlist);
 353                         if (!ret)
 354                                 throw new SocketException(11001);
 355 #endif
 356                         return (hostent_to_IPHostEntry (h_name, h_aliases, h_addrlist));
 357
 358                 }
 359
 360                 public static IPHostEntry GetHostEntry (string hostNameOrAddress)
 361                 {
 362                         if (hostNameOrAddress == null)
 363                                 throw new ArgumentNullException ("hostNameOrAddress");
 364                         if (hostNameOrAddress == "0.0.0.0" || hostNameOrAddress == "::0")
 365                                 throw new ArgumentException ("Addresses 0.0.0.0 (IPv4) " +
 366                                         "and ::0 (IPv6) are unspecified addresses. You " +
 367                                         "cannot use them as target address.",
 368                                         "hostNameOrAddress");
 369
 370                         IPAddress addr;
 371                         if (hostNameOrAddress.Length > 0 && IPAddress.TryParse (hostNameOrAddress, out addr))
 372                                 return GetHostEntry (addr);
 373
 374                         return GetHostByName (hostNameOrAddress);
 375                 }
 376
 377                 public static IPHostEntry GetHostEntry (IPAddress address)
 378                 {
 379                         if (address == null)
 380                                 throw new ArgumentNullException ("address");
 381
 382                         return GetHostByAddressFromString (address.ToString (), false);
 383                 }
 384
 385                 public static IPAddress [] GetHostAddresses (string hostNameOrAddress)
 386                 {
 387                         if (hostNameOrAddress == null)
 388                                 throw new ArgumentNullException ("hostNameOrAddress");
 389
 390                         if (hostNameOrAddress == "0.0.0.0" || hostNameOrAddress == "::0")
 391                                 throw new ArgumentException ("Addresses 0.0.0.0 (IPv4) " +
 392                                         "and ::0 (IPv6) are unspecified addresses. You " +
 393                                         "cannot use them as target address.",
 394                                         "hostNameOrAddress");
 395
 396                         IPAddress addr;
 397                         if (hostNameOrAddress.Length > 0 && IPAddress.TryParse (hostNameOrAddress, out addr))
 398                                 return new IPAddress[1] { addr };
 399
 400                         return GetHostEntry (hostNameOrAddress).AddressList;
 401                 }
 402
 403                 [Obsolete ("Use GetHostEntry instead")]
 404                 public static IPHostEntry GetHostByName (string hostName)
 405                 {
 406                         if (hostName == null)
 407                                 throw new ArgumentNullException ("hostName");
 408 #if TARGET_JVM
 409                         if (hostName.Length == 0)
 410                                 hostName = "localhost";
 411                         try {
 412                                 java.net.InetAddress[] iaArr = java.net.InetAddress.getAllByName(hostName);
 413                                 IPHostEntry host = new IPHostEntry();
 414                                 if (iaArr != null && iaArr.Length > 0)
 415                                 {
 416                                         host.HostName = iaArr[0].getHostName();
 417                                         IPAddress[] ipArr = new IPAddress[iaArr.Length];
 418                                         for (int i = 0; i < iaArr.Length; i++)
 419                                                 ipArr[i] = IPAddress.Parse(iaArr[i].getHostAddress());
 420
 421                                         host.AddressList = ipArr;
 422                                 }
 423                                 return host;
 424                         } catch (java.net.UnknownHostException jUHE) {
 425                                 throw new SocketException((int)SocketError.HostNotFound, jUHE.Message);
 426                         }
 427 #else
 428                         string h_name;
 429                         string[] h_aliases, h_addrlist;
 430
 431                         bool ret = GetHostByName_internal(hostName, out h_name, out h_aliases, out h_addrlist);
 432                         if (ret == false)
 433                                 throw new SocketException(11001);
 434
 435                         return(hostent_to_IPHostEntry(h_name, h_aliases, h_addrlist));
 436 #endif
 437                 }
 438
 439                 public static string GetHostName ()
 440                 {
 441 #if TARGET_JVM
 442                         return java.net.InetAddress.getLocalHost ().getHostName ();
 443 #else
 444                         string hostName;
 445
 446                         bool ret = GetHostName_internal(out hostName);
 447
 448                         if (ret == false)
 449                                 throw new SocketException(11001);
 450
 451                         return hostName;
 452 #endif
 453                 }
 454
 455                 [Obsolete ("Use GetHostEntry instead")]
 456                 public static IPHostEntry Resolve(string hostName)
 457                 {
 458                         if (hostName == null)
 459                                 throw new ArgumentNullException ("hostName");
 460
 461                         IPHostEntry ret = null;
 462
 463                         try {
 464                                 ret =  GetHostByAddress(hostName);
 465                         }
 466                         catch{}
 467
 468                         if(ret == null)
 469                                 ret =  GetHostByName(hostName);
 470
 471                         return ret;
 472                 }
 473
 474 #if NET_4_5
 475                 public static Task<IPAddress[]> GetHostAddressesAsync (string hostNameOrAddress)
 476                 {
 477                         return Task<IPAddress[]>.Factory.FromAsync (BeginGetHostAddresses, EndGetHostAddresses, hostNameOrAddress, null);
 478                 }
 479
 480                 public static Task<IPHostEntry> GetHostEntryAsync (IPAddress address)
 481                 {
 482                         return Task<IPHostEntry>.Factory.FromAsync (BeginGetHostEntry, EndGetHostEntry, address, null);
 483                 }
 484
 485                 public static Task<IPHostEntry> GetHostEntryAsync (string hostNameOrAddress)
 486                 {
 487                         return Task<IPHostEntry>.Factory.FromAsync (BeginGetHostEntry, EndGetHostEntry, hostNameOrAddress, null);
 488                 }
 489 #endif
 490         }
 491 }
 492