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

   1 //
   2 // System.Security.Permissions.UIPermission.cs
   3 //
   4 // Author
   5 //      Sebastien Pouliot  <sebastien@ximian.com>
   6 //
   7 // Copyright (C) 2003 Motus Technologies. http://www.motus.com
   8 // Copyright (C) 2004 Novell, Inc (http://www.novell.com)
   9 //
  10 // Permission is hereby granted, free of charge, to any person obtaining
  11 // a copy of this software and associated documentation files (the
  12 // "Software"), to deal in the Software without restriction, including
  13 // without limitation the rights to use, copy, modify, merge, publish,
  14 // distribute, sublicense, and/or sell copies of the Software, and to
  15 // permit persons to whom the Software is furnished to do so, subject to
  16 // the following conditions:
  17 //
  18 // The above copyright notice and this permission notice shall be
  19 // included in all copies or substantial portions of the Software.
  20 //
  21 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  22 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  23 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  24 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  25 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  26 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  27 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  28 //
  29
  30 using System.Globalization;
  31
  32 namespace System.Security.Permissions {
  33
  34         [Serializable]
  35         public sealed class UIPermission : CodeAccessPermission, IUnrestrictedPermission, IBuiltInPermission {
  36
  37                 private UIPermissionWindow _window;             // Note: this (looks like) but isn't a [Flags]
  38                 private UIPermissionClipboard _clipboard;       // Note: this (looks like) but isn't a [Flags]
  39
  40                 private const int version = 1;
  41
  42                 // Constructors
  43
  44                 public UIPermission (PermissionState state)
  45                 {
  46                         if (CheckPermissionState (state, true) == PermissionState.Unrestricted) {
  47                                 _clipboard = UIPermissionClipboard.AllClipboard;
  48                                 _window = UIPermissionWindow.AllWindows;
  49                         }
  50                 }
  51
  52                 public UIPermission (UIPermissionClipboard clipboardFlag)
  53                 {
  54                         // reuse validation by the Clipboard property
  55                         Clipboard = clipboardFlag;
  56                 }
  57
  58                 public UIPermission (UIPermissionWindow windowFlag)
  59                 {
  60                         // reuse validation by the Window property
  61                         Window = windowFlag;
  62                 }
  63
  64                 public UIPermission (UIPermissionWindow windowFlag, UIPermissionClipboard clipboardFlag)
  65                 {
  66                         // reuse validation by the Clipboard and Window properties
  67                         Clipboard = clipboardFlag;
  68                         Window = windowFlag;
  69                 }
  70
  71                 // Properties
  72
  73                 public UIPermissionClipboard Clipboard {
  74                         get { return _clipboard; }
  75                         set {
  76                                 if (!Enum.IsDefined (typeof (UIPermissionClipboard), value)) {
  77                                         string msg = String.Format (Locale.GetText ("Invalid enum {0}"), value);
  78                                         throw new ArgumentException (msg, "UIPermissionClipboard");
  79                                 }
  80                                 _clipboard = value;
  81                         }
  82                 }
  83
  84                 public UIPermissionWindow Window {
  85                         get { return _window; }
  86                         set {
  87                                 if (!Enum.IsDefined (typeof (UIPermissionWindow), value)) {
  88                                         string msg = String.Format (Locale.GetText ("Invalid enum {0}"), value);
  89                                         throw new ArgumentException (msg, "UIPermissionWindow");
  90                                 }
  91                                 _window = value;
  92                         }
  93                 }
  94
  95                 // Methods
  96
  97                 public override IPermission Copy ()
  98                 {
  99                         return new UIPermission (_window, _clipboard);
 100                 }
 101
 102                 public override void FromXml (SecurityElement esd)
 103                 {
 104                         // General validation in CodeAccessPermission
 105                         CheckSecurityElement (esd, "esd", version, version);
 106                         // Note: we do not (yet) care about the return value
 107                         // as we only accept version 1 (min/max values)
 108
 109                         if (IsUnrestricted (esd)) {
 110                                 _window = UIPermissionWindow.AllWindows;
 111                                 _clipboard = UIPermissionClipboard.AllClipboard;
 112                         }
 113                         else {
 114                                 string w = esd.Attribute ("Window");
 115                                 if (w == null)
 116                                         _window = UIPermissionWindow.NoWindows;
 117                                 else
 118                                         _window = (UIPermissionWindow) Enum.Parse (typeof (UIPermissionWindow), w);
 119
 120                                 string c = esd.Attribute ("Clipboard");
 121                                 if (c == null)
 122                                         _clipboard = UIPermissionClipboard.NoClipboard;
 123                                 else
 124                                         _clipboard = (UIPermissionClipboard) Enum.Parse (typeof (UIPermissionClipboard), c);
 125                         }
 126                 }
 127
 128                 public override IPermission Intersect (IPermission target)
 129                 {
 130                         UIPermission uip = Cast (target);
 131                         if (uip == null)
 132                                 return null;
 133
 134                         // there are not [Flags] so we can't use boolean operators
 135                         UIPermissionWindow w = ((_window < uip._window) ? _window : uip._window);
 136                         UIPermissionClipboard c = ((_clipboard < uip._clipboard) ? _clipboard : uip._clipboard);
 137
 138                         if (IsEmpty (w, c))
 139                                 return null;
 140
 141                         return new UIPermission (w, c);
 142                 }
 143
 144                 public override bool IsSubsetOf (IPermission target)
 145                 {
 146                         UIPermission uip = Cast (target);
 147                         if (uip == null)
 148                                 return IsEmpty (_window, _clipboard);
 149                         if (uip.IsUnrestricted ())
 150                                 return true;
 151
 152                         // there are not [Flags] so we can't use boolean operators
 153                         return ((_window <= uip._window) && (_clipboard <= uip._clipboard));
 154                 }
 155
 156                 public bool IsUnrestricted ()
 157                 {
 158                         return ((_window == UIPermissionWindow.AllWindows) &&
 159                                 (_clipboard == UIPermissionClipboard.AllClipboard));
 160                 }
 161
 162                 public override SecurityElement ToXml ()
 163                 {
 164                         SecurityElement e = Element (version);
 165
 166                         if (_window == UIPermissionWindow.AllWindows && _clipboard == UIPermissionClipboard.AllClipboard) {
 167                                 e.AddAttribute ("Unrestricted", "true");
 168                         }
 169                         else {
 170                                 if (_window != UIPermissionWindow.NoWindows)
 171                                         e.AddAttribute ("Window", _window.ToString ());
 172
 173                                 if (_clipboard != UIPermissionClipboard.NoClipboard)
 174                                         e.AddAttribute ("Clipboard", _clipboard.ToString ());
 175                         }
 176                         return e;
 177                 }
 178
 179                 public override IPermission Union (IPermission target)
 180                 {
 181                         UIPermission uip = Cast (target);
 182                         if (uip == null)
 183                                 return Copy ();
 184
 185                         // there are not [Flags] so we can't use boolean operators
 186                         UIPermissionWindow w = ((_window > uip._window) ? _window : uip._window);
 187                         UIPermissionClipboard c = ((_clipboard > uip._clipboard) ? _clipboard : uip._clipboard);
 188
 189                         if (IsEmpty (w, c))
 190                                 return null;
 191
 192                         return new UIPermission (w, c);
 193                 }
 194
 195                 // IBuiltInPermission
 196                 int IBuiltInPermission.GetTokenIndex ()
 197                 {
 198                         return (int) BuiltInToken.UI;
 199                 }
 200
 201                 // helpers
 202
 203                 private bool IsEmpty (UIPermissionWindow w, UIPermissionClipboard c)
 204                 {
 205                         return ((w == UIPermissionWindow.NoWindows) && (c == UIPermissionClipboard.NoClipboard));
 206                 }
 207
 208                 private UIPermission Cast (IPermission target)
 209                 {
 210                         if (target == null)
 211                                 return null;
 212
 213                         UIPermission uip = (target as UIPermission);
 214                         if (uip == null) {
 215                                 ThrowInvalidPermission (target, typeof (UIPermission));
 216                         }
 217
 218                         return uip;
 219                 }
 220         }
 221 }