mcs/class/System/System.Net/EndpointPermission.cs

   1 //\r
   2 // System.Net.EndpointPermission.cs\r
   3 //\r
   4 // Author:\r
   5 //   Lawrence Pit (loz@cable.a2000.nl)\r
   6 //\r
   7 \r
   8 using System;\r
   9 using System.Collections;\r
  10 using System.Security;\r
  11 using System.Security.Permissions;\r
  12 \r
  13 namespace System.Net\r
  14 {\r
  15         [Serializable]\r
  16         public class EndpointPermission // too bad about the lowercase p, not consistent with IPEndPoint ;)\r
  17         {\r
  18                 private static char [] dot_char = new char [] { '.' };\r
  19                 \r
  20                 // Fields\r
  21                 private string hostname;\r
  22                 private int port;\r
  23                 private TransportType transport;\r
  24 \r
  25                 private bool resolved;          \r
  26                 private bool hasWildcard;\r
  27                 private IPAddress [] addresses;\r
  28                 \r
  29                 // Constructors\r
  30                 internal EndpointPermission (string hostname, \r
  31                                              int port, \r
  32                                              TransportType transport) : base () \r
  33                 {                       \r
  34                         if (hostname == null)\r
  35                                 throw new ArgumentNullException ("hostname");\r
  36                         this.hostname = hostname;\r
  37                         this.port = port;\r
  38                         this.transport = transport;\r
  39                         this.resolved = false;\r
  40                         this.hasWildcard = false;\r
  41                         this.addresses = null;\r
  42                 }               \r
  43                 \r
  44                 // Properties\r
  45 \r
  46                 public string Hostname {\r
  47                         get { return hostname; }\r
  48                 }\r
  49 \r
  50                 public int Port {\r
  51                         get { return port; }\r
  52                 }\r
  53                 \r
  54                 public TransportType Transport {\r
  55                         get { return transport; }\r
  56                 }\r
  57                 \r
  58                 // Methods\r
  59                 \r
  60                 public override bool Equals (object obj) \r
  61                 {\r
  62                         EndpointPermission epp = obj as EndpointPermission;\r
  63                         return ((epp != null) &&\r
  64                                 (this.port == epp.port) &&\r
  65                                 (this.transport == epp.transport) &&\r
  66                                 (String.Compare (this.hostname, epp.hostname, true) == 0));\r
  67                 }\r
  68                 \r
  69                 public override int GetHashCode () \r
  70                 {\r
  71                         return ToString ().GetHashCode ();\r
  72                 }\r
  73                 \r
  74                 public override string ToString () \r
  75                 {\r
  76                         return hostname + "#" + port + "#" + (int) transport;\r
  77                 }\r
  78                 \r
  79                 // Internal & Private Methods\r
  80                 \r
  81                 internal bool IsSubsetOf (EndpointPermission perm) \r
  82                 {\r
  83                         if (perm == null)\r
  84                                 return false;\r
  85                         \r
  86                         if (perm.port != SocketPermission.AllPorts &&\r
  87                             this.port != perm.port)\r
  88                                 return false;\r
  89                         \r
  90                         if (perm.transport != TransportType.All &&\r
  91                             this.transport != perm.transport)\r
  92                                 return false;\r
  93                         \r
  94                         this.Resolve ();\r
  95                         perm.Resolve ();\r
  96                         \r
  97                         if (this.hasWildcard) {\r
  98                                 if (perm.hasWildcard)\r
  99                                         return IsSubsetOf (this.hostname, perm.hostname);\r
 100                                 else \r
 101                                         return false;\r
 102                         } \r
 103                         \r
 104                         if (this.addresses == null) \r
 105                                 return false;\r
 106                         \r
 107                         if (perm.hasWildcard) \r
 108                                 // a bit dubious... should they all be a subset or is one \r
 109                                 // enough in this case?\r
 110                                 foreach (IPAddress addr in this.addresses)\r
 111                                         if (IsSubsetOf (addr.ToString (), perm.hostname))\r
 112                                                 return true;\r
 113                                 \r
 114                         if (perm.addresses == null) \r
 115                                 return false;\r
 116                                 \r
 117                         // a bit dubious... should they all be a subset or is one \r
 118                         // enough in this case?\r
 119                         foreach (IPAddress addr in perm.addresses)\r
 120                                 if (IsSubsetOf (this.hostname, addr.ToString ())) \r
 121                                         return true;    \r
 122                                         \r
 123                         return false;           \r
 124                 }               \r
 125                 \r
 126                 private bool IsSubsetOf (string addr1, string addr2)\r
 127                 {\r
 128                         string [] h1 = addr1.Split (dot_char);          \r
 129                         string [] h2 = addr2.Split (dot_char);\r
 130                                 \r
 131                         for (int i = 0; i < 4; i++) {\r
 132                                 int part1 = ToNumber (h1 [i]);\r
 133                                 if (part1 == -1) \r
 134                                         return false;                           \r
 135 \r
 136                                 int part2 = ToNumber (h2 [i]);\r
 137                                 if (part2 == -1)\r
 138                                         return false;                           \r
 139                                 if (part1 != part2 && part2 != 256)\r
 140                                         return false;\r
 141                         }\r
 142                         return true;\r
 143                 }\r
 144                 \r
 145                 internal EndpointPermission Intersect (EndpointPermission perm) \r
 146                 {\r
 147                         if (perm == null)\r
 148                                 return null;\r
 149                         \r
 150                         int _port;\r
 151                         if (this.port == perm.port)\r
 152                                 _port = this.port;\r
 153                         else if (this.port == SocketPermission.AllPorts)\r
 154                                 _port = perm.port;\r
 155                         else if (perm.port == SocketPermission.AllPorts)\r
 156                                 _port = this.port;\r
 157                         else\r
 158                                 return null;\r
 159 \r
 160                         TransportType _transport;\r
 161                         if (this.transport == perm.transport)\r
 162                                 _transport = this.transport;\r
 163                         else if (this.transport == TransportType.All)\r
 164                                 _transport = perm.transport;\r
 165                         else if (perm.transport == TransportType.All)\r
 166                                 _transport = this.transport;\r
 167                         else\r
 168                                 return null;\r
 169 \r
 170                         string _hostname = IntersectHostname (perm);                                            \r
 171                         \r
 172                         if (_hostname == null)\r
 173                                 return null;\r
 174 \r
 175                         if (!this.hasWildcard)\r
 176                                 return this;\r
 177                                 \r
 178                         if (!perm.hasWildcard)\r
 179                                 return perm;\r
 180                                 \r
 181                         EndpointPermission newperm = new EndpointPermission (_hostname, _port, _transport);\r
 182                         newperm.hasWildcard = true;\r
 183                         newperm.resolved = true;\r
 184                         return newperm;\r
 185                 }\r
 186                 \r
 187                 private string IntersectHostname (EndpointPermission perm)\r
 188                 {\r
 189                         if (this.hostname == perm.hostname)\r
 190                                 return this.hostname;\r
 191                                 \r
 192                         this.Resolve ();\r
 193                         perm.Resolve ();\r
 194                         \r
 195                         string _hostname = null;\r
 196                         \r
 197                         if (this.hasWildcard) {\r
 198                                 if (perm.hasWildcard) {\r
 199                                         _hostname = Intersect (this.hostname, perm.hostname);\r
 200                                 } else if (perm.addresses != null) {\r
 201                                         for (int j = 0; j < perm.addresses.Length; j++) {\r
 202                                                 _hostname = Intersect (this.hostname, perm.addresses [j].ToString ());\r
 203                                                 if (_hostname != null) \r
 204                                                         break;\r
 205                                         }\r
 206                                 }\r
 207                         } else if (this.addresses != null) {\r
 208                                 for (int i = 0; i < this.addresses.Length; i++) {\r
 209                                         string thisaddr = this.addresses [i].ToString ();\r
 210                                         if (perm.hasWildcard) {\r
 211                                                 _hostname = Intersect (thisaddr, perm.hostname);\r
 212                                         } else if (perm.addresses != null) {\r
 213                                                 for (int j = 0; j < perm.addresses.Length; j++) {\r
 214                                                         _hostname = Intersect (thisaddr, perm.addresses [j].ToString ());\r
 215                                                         if (_hostname != null) \r
 216                                                                 break;\r
 217                                                 }\r
 218                                         }\r
 219                                 }\r
 220                         }\r
 221                         \r
 222                         return _hostname;\r
 223                 }\r
 224                 \r
 225                 // alas, currently we'll only support IPv4 as that's MS.Net behaviour\r
 226                 // returns null when both host strings do not intersect\r
 227                 private string Intersect (string addr1, string addr2)\r
 228                 {\r
 229                         string [] h1 = addr1.Split (dot_char);          \r
 230                         string [] h2 = addr2.Split (dot_char);\r
 231                                 \r
 232                         string [] s = new string [7];\r
 233                         for (int i = 0; i < 4; i++) {\r
 234                                 int part1 = ToNumber (h1 [i]);\r
 235                                 if (part1 == -1) \r
 236                                         return null;                            \r
 237 \r
 238                                 int part2 = ToNumber (h2 [i]);\r
 239                                 if (part2 == -1)\r
 240                                         return null;                            \r
 241 \r
 242                                 if (part1 == 256) \r
 243                                         s [i << 1] = (part2 == 256) ? "*" : String.Empty + part2;\r
 244                                 else if (part2 == 256)\r
 245                                         s [i << 1] = (part1 == 256) ? "*" : String.Empty + part1;                               \r
 246                                 else if (part1 == part2)\r
 247                                         s [i << 1] = String.Empty + part1;\r
 248                                 else\r
 249                                         return null;\r
 250                         }\r
 251                         \r
 252                         s [1] = s [3] = s [5] = ".";\r
 253                         return String.Concat (s);\r
 254                 }\r
 255                 \r
 256                 // returns 256 if value is a '*' character\r
 257                 // returns -1 if value isn't a number between 0 and 255         \r
 258                 private int ToNumber (string value)\r
 259                 {\r
 260                         if (value == "*")\r
 261                                 return 256;\r
 262                                 \r
 263                         int len = value.Length;\r
 264                         if (len < 1 || len > 3)\r
 265                                 return -1;\r
 266                                 \r
 267                         int val = 0;                            \r
 268                         for (int i = 0; i < len; i++) {\r
 269                                 char c = value [i];\r
 270                                 if ('0' <= c && c <= '9') \r
 271                                         val = checked (val * 10 + (c - '0'));\r
 272                                 else\r
 273                                         return -1;\r
 274                         }\r
 275                         \r
 276                         return val <= 255 ? val : -1;\r
 277                 }\r
 278 \r
 279                 internal void Resolve ()\r
 280                 {\r
 281                         if (resolved)   \r
 282                                 return;\r
 283                                 \r
 284                         bool isHostname = false;                                \r
 285                         bool hasWildcard = false;\r
 286                         this.addresses = null;\r
 287                         \r
 288                         string [] s = hostname.Split (dot_char);\r
 289 \r
 290                         if (s.Length != 4) {\r
 291                                 isHostname = true;\r
 292                         } else {\r
 293                                 for (int i = 0; i < 4; i++) {\r
 294                                         int quad = ToNumber (s [i]);\r
 295                                         if (quad == -1) {\r
 296                                                 isHostname = true;\r
 297                                                 break;\r
 298                                         }\r
 299                                         if (quad == 256)\r
 300                                                 hasWildcard = true;\r
 301                                 }\r
 302                         }\r
 303                         \r
 304                         if (isHostname) {\r
 305                                 this.hasWildcard = false;\r
 306                                 try {\r
 307                                         this.addresses = Dns.GetHostByName (hostname).AddressList;\r
 308                                 } catch (System.Net.Sockets.SocketException) {                                  \r
 309                                 }\r
 310                         } else {\r
 311                                 this.hasWildcard = hasWildcard;\r
 312                                 if (!hasWildcard) {\r
 313                                         addresses = new IPAddress [1];\r
 314                                         addresses [0] = IPAddress.Parse (hostname);\r
 315                                 }\r
 316                         }\r
 317                         \r
 318                         this.resolved = true;                           \r
 319                 }\r
 320                 \r
 321                 internal void UndoResolve ()\r
 322                 {\r
 323                         resolved = false;\r
 324                 }\r
 325         }\r
 326 }\r