mcs/class/corlib/System.Security.Permissions/EnvironmentPermission.cs

   1 //
   2 // System.Security.Permissions.EnvironmentPermission.cs
   3 //
   4 // Authors:
   5 //      Tim Coleman <tim@timcoleman.com>
   6 //      Sebastien Pouliot <spouliot@motus.com>
   7 //
   8 // Copyright (C) 2002, Tim Coleman
   9 // Portions Copyright (C) 2003 Motus Technologies (http://www.motus.com)
  10 //
  11
  12 //
  13 // Copyright (C) 2004 Novell, Inc (http://www.novell.com)
  14 //
  15 // Permission is hereby granted, free of charge, to any person obtaining
  16 // a copy of this software and associated documentation files (the
  17 // "Software"), to deal in the Software without restriction, including
  18 // without limitation the rights to use, copy, modify, merge, publish,
  19 // distribute, sublicense, and/or sell copies of the Software, and to
  20 // permit persons to whom the Software is furnished to do so, subject to
  21 // the following conditions:
  22 //
  23 // The above copyright notice and this permission notice shall be
  24 // included in all copies or substantial portions of the Software.
  25 //
  26 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  27 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  28 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  29 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  30 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  31 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  32 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  33 //
  34
  35 using System;
  36 using System.Collections;
  37 using System.Security.Permissions;
  38 using System.Text;
  39
  40 namespace System.Security.Permissions {
  41
  42         [Serializable]
  43         public sealed class EnvironmentPermission : CodeAccessPermission, IUnrestrictedPermission, IBuiltInPermission {
  44
  45                 #region Fields
  46
  47                 EnvironmentPermissionAccess flags;
  48                 PermissionState _state;
  49                 ArrayList readList;
  50                 ArrayList writeList;
  51
  52                 #endregion // Fields
  53
  54                 #region Constructors
  55
  56                 public EnvironmentPermission (PermissionState state) : base ()
  57                 {
  58                         switch (state) {
  59                                 case PermissionState.None:
  60                                 case PermissionState.Unrestricted:
  61                                         _state = state;
  62                                         readList = new ArrayList ();
  63                                         writeList = new ArrayList ();
  64                                         break;
  65                                 default:
  66                                         throw new ArgumentException ("Invalid PermissionState", "state");
  67                         }
  68                 }
  69
  70                 public EnvironmentPermission (EnvironmentPermissionAccess flag, string pathList) : base ()
  71                 {
  72                         readList = new ArrayList ();
  73                         writeList = new ArrayList ();
  74                         SetPathList (flag, pathList);
  75                 }
  76
  77                 #endregion // Constructors
  78
  79                 #region Methods
  80
  81                 public void AddPathList (EnvironmentPermissionAccess flag, string pathList)
  82                 {
  83                         if (pathList == null)
  84                                 throw new ArgumentNullException ("pathList");
  85                         string[] paths;
  86                         switch (flag) {
  87                                 case EnvironmentPermissionAccess.AllAccess:
  88                                         paths = pathList.Split (';');
  89                                         foreach (string path in paths) {
  90                                                 if (!readList.Contains (path))
  91                                                         readList.Add (path);
  92                                                 if (!writeList.Contains (path))
  93                                                         writeList.Add (path);
  94                                         }
  95                                         break;
  96                                 case EnvironmentPermissionAccess.NoAccess:
  97                                         // ??? unit tests doesn't show removal using NoAccess ???
  98                                         break;
  99                                 case EnvironmentPermissionAccess.Read:
 100                                         paths = pathList.Split (';');
 101                                         foreach (string path in paths) {
 102                                                 if (!readList.Contains (path))
 103                                                         readList.Add (path);
 104                                         }
 105                                         break;
 106                                 case EnvironmentPermissionAccess.Write:
 107                                         paths = pathList.Split (';');
 108                                         foreach (string path in paths) {
 109                                                 if (!writeList.Contains (path))
 110                                                         writeList.Add (path);
 111                                         }
 112                                         break;
 113                                 default:
 114                                         throw new ArgumentException ("Invalid EnvironmentPermissionAccess", "flag");
 115                         }
 116                 }
 117
 118                 public override IPermission Copy ()
 119                 {
 120                         EnvironmentPermission ep = new EnvironmentPermission (_state);
 121                         string path = GetPathList (EnvironmentPermissionAccess.Read);
 122                         if (path != null)
 123                                 ep.SetPathList (EnvironmentPermissionAccess.Read, path);
 124                         path = GetPathList (EnvironmentPermissionAccess.Write);
 125                         if (path != null)
 126                                 ep.SetPathList (EnvironmentPermissionAccess.Write, path);
 127                         return ep;
 128                 }
 129
 130                 public override void FromXml (SecurityElement esd)
 131                 {
 132                         if (esd == null)
 133                                 throw new ArgumentNullException ("esd");
 134                         if (esd.Tag != "IPermission")
 135                                 throw new ArgumentException ("not IPermission");
 136                         if (!(esd.Attributes ["class"] as string).StartsWith ("System.Security.Permissions.EnvironmentPermission"))
 137                                 throw new ArgumentException ("not EnvironmentPermission");
 138                         if ((esd.Attributes ["version"] as string) != "1")
 139                                 throw new ArgumentException ("wrong version");
 140
 141                         string read = (esd.Attributes ["Read"] as string);
 142                         if ((read != null) && (read.Length > 0))
 143                                 SetPathList (EnvironmentPermissionAccess.Read, read);
 144                         string write = (esd.Attributes ["Write"] as string);
 145                         if ((write != null) && (write.Length > 0))
 146                                 SetPathList (EnvironmentPermissionAccess.Write, write);
 147
 148                         // Unrestricted ???
 149                 }
 150
 151                 public string GetPathList (EnvironmentPermissionAccess flag)
 152                 {
 153                         StringBuilder sb = new StringBuilder ();
 154                         switch (flag) {
 155                                 case EnvironmentPermissionAccess.AllAccess:
 156                                 case EnvironmentPermissionAccess.NoAccess:
 157                                         throw new ArgumentException ("Invalid EnvironmentPermissionAccess in context", "flag");
 158                                 case EnvironmentPermissionAccess.Read:
 159                                         foreach (string path in readList) {
 160                                                 sb.Append (path);
 161                                                 sb.Append (";");
 162                                         }
 163                                         break;
 164                                 case EnvironmentPermissionAccess.Write:
 165                                         foreach (string path in writeList) {
 166                                                 sb.Append (path);
 167                                                 sb.Append (";");
 168                                         }
 169                                         break;
 170                                 default:
 171                                         throw new ArgumentException ("Unknown EnvironmentPermissionAccess", "flag");
 172                         }
 173                         string result = sb.ToString ();
 174                         // remove last ';'
 175                         int n = result.Length;
 176                         if (n > 0)
 177                                 return result.Substring (0, n - 1);
 178                         return ((_state == PermissionState.Unrestricted) ? String.Empty : null);
 179                 }
 180
 181                 public override IPermission Intersect (IPermission target)
 182                 {
 183                         if (target == null)
 184                                 return null;
 185                         if (! (target is EnvironmentPermission))
 186                                 throw new ArgumentException ("wrong type");
 187
 188                         EnvironmentPermission o = (EnvironmentPermission) target;
 189                         int n = 0;
 190                         if (IsUnrestricted ())
 191                                 return o.Copy ();
 192                         if (o.IsUnrestricted ())
 193                                 return Copy ();
 194
 195                         EnvironmentPermission ep = new EnvironmentPermission (PermissionState.None);
 196                         string readTarget = o.GetPathList (EnvironmentPermissionAccess.Read);
 197                         if (readTarget != null) {
 198                                 string[] targets = readTarget.Split (';');
 199                                 foreach (string t in targets) {
 200                                         if (readList.Contains (t)) {
 201                                                 ep.AddPathList (EnvironmentPermissionAccess.Read, t);
 202                                                 n++;
 203                                         }
 204                                 }
 205                         }
 206
 207                         string writeTarget = o.GetPathList (EnvironmentPermissionAccess.Write);
 208                         if (writeTarget != null) {
 209                                 string[] targets = writeTarget.Split (';');
 210                                 foreach (string t in targets) {
 211                                         if (writeList.Contains (t)) {
 212                                                 ep.AddPathList (EnvironmentPermissionAccess.Write, t);
 213                                                 n++;
 214                                         }
 215                                 }
 216                         }
 217                         return ((n > 0) ? ep : null);
 218                 }
 219
 220                 public override bool IsSubsetOf (IPermission target)
 221                 {
 222                         if (target == null)
 223                                 return false;
 224
 225                         if (! (target is EnvironmentPermission))
 226                                 throw new ArgumentException ("wrong type");
 227
 228                         EnvironmentPermission o = (EnvironmentPermission) target;
 229                         if (IsUnrestricted ())
 230                                 return o.IsUnrestricted ();
 231                         else if (o.IsUnrestricted ())
 232                                 return true;
 233
 234                         foreach (string s in readList) {
 235                                 if (!o.readList.Contains (s))
 236                                         return false;
 237                         }
 238
 239                         foreach (string s in writeList) {
 240                                 if (!o.writeList.Contains (s))
 241                                         return false;
 242                         }
 243
 244                         return true;
 245                 }
 246
 247                 public bool IsUnrestricted ()
 248                 {
 249                         return (_state == PermissionState.Unrestricted);
 250                 }
 251
 252                 public void SetPathList (EnvironmentPermissionAccess flag, string pathList)
 253                 {
 254                         if (pathList == null)
 255                                 throw new ArgumentNullException ("pathList");
 256                         string[] paths;
 257                         switch (flag) {
 258                                 case EnvironmentPermissionAccess.AllAccess:
 259                                         readList.Clear ();
 260                                         writeList.Clear ();
 261                                         paths = pathList.Split (';');
 262                                         foreach (string path in paths) {
 263                                                 readList.Add (path);
 264                                                 writeList.Add (path);
 265                                         }
 266                                         break;
 267                                 case EnvironmentPermissionAccess.NoAccess:
 268                                         // ??? unit tests doesn't show removal using NoAccess ???
 269                                         break;
 270                                 case EnvironmentPermissionAccess.Read:
 271                                         readList.Clear ();
 272                                         paths = pathList.Split (';');
 273                                         foreach (string path in paths) {
 274                                                 readList.Add (path);
 275                                         }
 276                                         break;
 277                                 case EnvironmentPermissionAccess.Write:
 278                                         writeList.Clear ();
 279                                         paths = pathList.Split (';');
 280                                         foreach (string path in paths) {
 281                                                 writeList.Add (path);
 282                                         }
 283                                         break;
 284                                 default:
 285                                         throw new ArgumentException ("Invalid EnvironmentPermissionAccess", "flag");
 286                         }
 287                 }
 288
 289                 public override SecurityElement ToXml ()
 290                 {
 291                         SecurityElement se = Element (this, 1);
 292                         if (_state == PermissionState.Unrestricted) {
 293                                 se.AddAttribute ("Unrestricted", "true");
 294                         }
 295                         else {
 296                                 string path = GetPathList (EnvironmentPermissionAccess.Read);
 297                                 if (path != null)
 298                                         se.AddAttribute ("Read", path);
 299                                 path = GetPathList (EnvironmentPermissionAccess.Write);
 300                                 if (path != null)
 301                                         se.AddAttribute ("Write", path);
 302                         }
 303                         return se;
 304                 }
 305
 306                 public override IPermission Union (IPermission other)
 307                 {
 308                         if (other == null)
 309                                 return Copy ();
 310                         if (! (other is EnvironmentPermission))
 311                                 throw new ArgumentException ("wrong type");
 312
 313                         EnvironmentPermission o = (EnvironmentPermission) other;
 314                         if (IsUnrestricted () || o.IsUnrestricted ())
 315                                 return new EnvironmentPermission (PermissionState.Unrestricted);
 316
 317                         EnvironmentPermission ep = (EnvironmentPermission) Copy ();
 318                         string path = o.GetPathList (EnvironmentPermissionAccess.Read);
 319                         if (path != null)
 320                                 ep.AddPathList (EnvironmentPermissionAccess.Read, path);
 321                         path = o.GetPathList (EnvironmentPermissionAccess.Write);
 322                         if (path != null)
 323                                 ep.AddPathList (EnvironmentPermissionAccess.Write, path);
 324                         return ep;
 325                 }
 326
 327                 // IBuiltInPermission
 328                 int IBuiltInPermission.GetTokenIndex ()
 329                 {
 330                         return 0;
 331                 }
 332
 333                 #endregion // Methods
 334         }
 335 }