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

   1 // System.Net.Dns.cs
   2 //
   3 // Author: Mads Pultz (mpultz@diku.dk)
   4 // Author: Lawrence Pit (loz@cable.a2000.nl)
   5 //
   6 // (C) Mads Pultz, 2001
   7
   8 //
   9 // Permission is hereby granted, free of charge, to any person obtaining
  10 // a copy of this software and associated documentation files (the
  11 // "Software"), to deal in the Software without restriction, including
  12 // without limitation the rights to use, copy, modify, merge, publish,
  13 // distribute, sublicense, and/or sell copies of the Software, and to
  14 // permit persons to whom the Software is furnished to do so, subject to
  15 // the following conditions:
  16 //
  17 // The above copyright notice and this permission notice shall be
  18 // included in all copies or substantial portions of the Software.
  19 //
  20 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  21 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  22 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  23 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  24 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  25 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  26 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  27 //
  28
  29 using System;
  30 using System.Net.Sockets;
  31 using System.Text;
  32 using System.Collections;
  33 using System.Threading;
  34 using System.Runtime.CompilerServices;
  35 using System.Runtime.Remoting.Messaging;
  36
  37 namespace System.Net {
  38 #if NET_2_0
  39         public static class Dns {
  40 #else
  41         public sealed class Dns {
  42
  43                 private Dns () {}
  44 #endif
  45
  46                 static Dns ()
  47                 {
  48                         System.Net.Sockets.Socket.CheckProtocolSupport();
  49                 }
  50
  51                 private delegate IPHostEntry GetHostByNameCallback (string hostName);
  52                 private delegate IPHostEntry ResolveCallback (string hostName);
  53 #if NET_2_0
  54                 private delegate IPHostEntry GetHostEntryNameCallback (string hostName);
  55                 private delegate IPHostEntry GetHostEntryIPCallback (IPAddress hostAddress);
  56                 private delegate IPAddress [] GetHostAddressesCallback (string hostName);
  57 #endif
  58
  59 #if NET_2_0
  60                 [Obsolete ("Use BeginGetHostEntry instead")]
  61 #endif
  62                 public static IAsyncResult BeginGetHostByName (string hostName,
  63                         AsyncCallback requestCallback, object stateObject)
  64                 {
  65                         if (hostName == null)
  66                                 throw new ArgumentNullException ("hostName");
  67
  68                         GetHostByNameCallback c = new GetHostByNameCallback (GetHostByName);
  69                         return c.BeginInvoke (hostName, requestCallback, stateObject);
  70                 }
  71
  72 #if NET_2_0
  73                 [Obsolete ("Use BeginGetHostEntry instead")]
  74 #endif
  75                 public static IAsyncResult BeginResolve (string hostName,
  76                         AsyncCallback requestCallback, object stateObject)
  77                 {
  78                         if (hostName == null)
  79                                 throw new ArgumentNullException ("hostName");
  80
  81                         ResolveCallback c = new ResolveCallback (Resolve);
  82                         return c.BeginInvoke (hostName, requestCallback, stateObject);
  83                 }
  84
  85 #if NET_2_0
  86                 public static IAsyncResult BeginGetHostAddresses (string hostName,
  87                         AsyncCallback requestCallback, object stateObject)
  88                 {
  89                         if (hostName == null)
  90                                 throw new ArgumentNullException ("hostName");
  91
  92                         GetHostAddressesCallback c = new GetHostAddressesCallback (GetHostAddresses);
  93                         return c.BeginInvoke (hostName, requestCallback, stateObject);
  94                 }
  95
  96                 public static IAsyncResult BeginGetHostEntry (string hostNameOrAddress,
  97                         AsyncCallback requestCallback, object stateObject)
  98                 {
  99                         if (hostNameOrAddress == null)
 100                                 throw new ArgumentNullException ("hostNameOrAddress");
 101
 102                         GetHostEntryNameCallback c = new GetHostEntryNameCallback (GetHostEntry);
 103                         return c.BeginInvoke (hostNameOrAddress, requestCallback, stateObject);
 104                 }
 105
 106                 public static IAsyncResult BeginGetHostEntry (IPAddress hostAddress,
 107                         AsyncCallback requestCallback, object stateObject)
 108                 {
 109                         if (hostAddress == null)
 110                                 throw new ArgumentNullException ("hostAddress");
 111
 112                         GetHostEntryIPCallback c = new GetHostEntryIPCallback (GetHostEntry);
 113                         return c.BeginInvoke (hostAddress, requestCallback, stateObject);
 114                 }
 115 #endif
 116
 117 #if NET_2_0
 118                 [Obsolete ("Use EndGetHostEntry instead")]
 119 #endif
 120                 public static IPHostEntry EndGetHostByName (IAsyncResult asyncResult)
 121                 {
 122                         if (asyncResult == null)
 123                                 throw new ArgumentNullException ("asyncResult");
 124
 125                         AsyncResult async = (AsyncResult) asyncResult;
 126                         GetHostByNameCallback cb = (GetHostByNameCallback) async.AsyncDelegate;
 127                         return cb.EndInvoke(asyncResult);
 128                 }
 129
 130 #if NET_2_0
 131                 [Obsolete ("Use EndGetHostEntry instead")]
 132 #endif
 133                 public static IPHostEntry EndResolve (IAsyncResult asyncResult)
 134                 {
 135                         if (asyncResult == null)
 136                                 throw new ArgumentNullException ("asyncResult");
 137                         AsyncResult async = (AsyncResult) asyncResult;
 138                         ResolveCallback cb = (ResolveCallback) async.AsyncDelegate;
 139                         return cb.EndInvoke(asyncResult);
 140                 }
 141
 142 #if NET_2_0
 143
 144                 public static IPAddress [] EndGetHostAddresses (IAsyncResult asyncResult)
 145                 {
 146                         if (asyncResult == null)
 147                                 throw new ArgumentNullException ("asyncResult");
 148
 149                         AsyncResult async = (AsyncResult) asyncResult;
 150                         GetHostAddressesCallback cb = (GetHostAddressesCallback) async.AsyncDelegate;
 151                         return cb.EndInvoke(asyncResult);
 152                 }
 153
 154                 public static IPHostEntry EndGetHostEntry (IAsyncResult asyncResult)
 155                 {
 156                         if (asyncResult == null)
 157                                 throw new ArgumentNullException ("asyncResult");
 158                         AsyncResult async = (AsyncResult) asyncResult;
 159 #if NET_2_0
 160                         if (async.AsyncDelegate is GetHostEntryIPCallback)
 161                                 return ((GetHostEntryIPCallback) async.AsyncDelegate).EndInvoke (asyncResult);
 162 #endif
 163                         GetHostEntryNameCallback cb = (GetHostEntryNameCallback) async.AsyncDelegate;
 164                         return cb.EndInvoke(asyncResult);
 165                 }
 166 #endif
 167
 168                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
 169                 private extern static bool GetHostByName_internal(string host, out string h_name, out string[] h_aliases, out string[] h_addr_list);
 170
 171                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
 172                 private extern static bool GetHostByAddr_internal(string addr, out string h_name, out string[] h_aliases, out string[] h_addr_list);
 173
 174                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
 175                 private extern static bool GetHostName_internal(out string h_name);
 176
 177                 private static IPHostEntry hostent_to_IPHostEntry(string h_name, string[] h_aliases, string[] h_addrlist)
 178                 {
 179                         IPHostEntry he = new IPHostEntry();
 180                         ArrayList addrlist = new ArrayList();
 181
 182                         he.HostName = h_name;
 183                         he.Aliases = h_aliases;
 184                         for(int i=0; i<h_addrlist.Length; i++) {
 185                                 try {
 186                                         IPAddress newAddress = IPAddress.Parse(h_addrlist[i]);
 187
 188                                         if( (Socket.SupportsIPv6 && newAddress.AddressFamily == AddressFamily.InterNetworkV6) ||
 189                                             (Socket.SupportsIPv4 && newAddress.AddressFamily == AddressFamily.InterNetwork) )
 190                                                 addrlist.Add(newAddress);
 191                                 } catch (ArgumentNullException) {
 192                                         /* Ignore this, as the
 193                                          * internal call might have
 194                                          * left some blank entries at
 195                                          * the end of the array
 196                                          */
 197                                 }
 198                         }
 199
 200                         if(addrlist.Count == 0)
 201                                 throw new SocketException(11001);
 202
 203                         he.AddressList = addrlist.ToArray(typeof(IPAddress)) as IPAddress[];
 204                         return he;
 205                 }
 206
 207 #if NET_2_0
 208                 [Obsolete ("Use GetHostEntry instead")]
 209 #endif
 210                 public static IPHostEntry GetHostByAddress(IPAddress address)
 211                 {
 212                         if (address == null)
 213                                 throw new ArgumentNullException ("address");
 214
 215                         return GetHostByAddressFromString (address.ToString (), false);
 216                 }
 217
 218 #if NET_2_0
 219                 [Obsolete ("Use GetHostEntry instead")]
 220 #endif
 221                 public static IPHostEntry GetHostByAddress(string address)
 222                 {
 223                         if (address == null)
 224                                 throw new ArgumentNullException ("address");
 225
 226                         return GetHostByAddressFromString (address, true);
 227                 }
 228
 229                 static IPHostEntry GetHostByAddressFromString (string address, bool parse)
 230                 {
 231                         // Undocumented MS behavior: when called with IF_ANY,
 232                         // this should return the local host
 233                         if (address.Equals ("0.0.0.0")) {
 234                                 address = "127.0.0.1";
 235                                 parse = false;
 236                         }
 237
 238                         // Must check the IP format, might send an exception if invalid string.
 239                         if (parse)
 240                                 IPAddress.Parse(address);
 241
 242                         string h_name;
 243                         string[] h_aliases, h_addrlist;
 244
 245                         bool ret = GetHostByAddr_internal(address, out h_name, out h_aliases, out h_addrlist);
 246                         if (!ret)
 247                                 throw new SocketException(11001);
 248
 249                         return (hostent_to_IPHostEntry (h_name, h_aliases, h_addrlist));
 250                 }
 251
 252 #if NET_2_0
 253                 public static IPHostEntry GetHostEntry (string hostNameOrAddress)
 254                 {
 255                         if (hostNameOrAddress == null)
 256                                 throw new ArgumentNullException ("hostNameOrAddress");
 257
 258                         if (hostNameOrAddress == "0.0.0.0")
 259                                 hostNameOrAddress = "127.0.0.1";
 260                         IPAddress addr;
 261                         if (IPAddress.TryParse (hostNameOrAddress, out addr))
 262                                 return GetHostEntry (addr);
 263                         else
 264                                 return GetHostByName (hostNameOrAddress);
 265                 }
 266
 267                 public static IPHostEntry GetHostEntry (IPAddress address)
 268                 {
 269                         if (address == null)
 270                                 throw new ArgumentNullException ("address");
 271
 272                         return GetHostByAddressFromString (address.ToString (), false);
 273                 }
 274
 275                 public static IPAddress [] GetHostAddresses (string hostNameOrAddress)
 276                 {
 277                         if (hostNameOrAddress == null)
 278                                 throw new ArgumentNullException ("hostNameOrAddress");
 279
 280                         return GetHostEntry (hostNameOrAddress).AddressList;
 281                 }
 282 #endif
 283
 284 #if NET_2_0
 285                 [Obsolete ("Use GetHostEntry instead")]
 286 #endif
 287                 public static IPHostEntry GetHostByName(string hostName)
 288                 {
 289                         if (hostName == null)
 290                                 throw new ArgumentNullException();
 291
 292                         string h_name;
 293                         string[] h_aliases, h_addrlist;
 294
 295                         bool ret = GetHostByName_internal(hostName, out h_name,
 296                                 out h_aliases,
 297                                 out h_addrlist);
 298                         if (ret == false)
 299                                 throw new SocketException(11001);
 300
 301                         return(hostent_to_IPHostEntry(h_name, h_aliases,
 302                                 h_addrlist));
 303                 }
 304
 305                 public static string GetHostName()
 306                 {
 307                         string hostName;
 308
 309                         bool ret = GetHostName_internal(out hostName);
 310
 311                         if (ret == false)
 312                                 throw new SocketException(11001);
 313
 314                         return hostName;
 315                 }
 316
 317 #if NET_2_0
 318                 [Obsolete ("Use GetHostEntry instead")]
 319 #endif
 320                 public static IPHostEntry Resolve(string hostName)
 321                 {
 322                         if (hostName == null)
 323                                 throw new ArgumentNullException ("hostName");
 324
 325                         IPHostEntry ret = null;
 326
 327                         try {
 328                                 ret =  GetHostByAddress(hostName);
 329                         }
 330                         catch{}
 331
 332                         if(ret == null)
 333                                 ret =  GetHostByName(hostName);
 334
 335                         return ret;
 336                 }
 337         }
 338 }
 339