mcs/class/System.Drawing/System.Drawing.Printing/PrintingPermission.cs

   1 //
   2 // System.Drawing.PrintingPermission.cs
   3 //
   4 // Authors:
   5 //      Dennis Hayes (dennish@Raytek.com)
   6 //      Herve Poussineau (hpoussineau@fr.st)
   7 //      Sebastien Pouliot  <sebastien@ximian.com>
   8 //
   9 // (C) 2002 Ximian, Inc
  10 // Copyright (C) 2004 Novell, Inc (http://www.novell.com)
  11 //
  12 // Permission is hereby granted, free of charge, to any person obtaining
  13 // a copy of this software and associated documentation files (the
  14 // "Software"), to deal in the Software without restriction, including
  15 // without limitation the rights to use, copy, modify, merge, publish,
  16 // distribute, sublicense, and/or sell copies of the Software, and to
  17 // permit persons to whom the Software is furnished to do so, subject to
  18 // the following conditions:
  19 //
  20 // The above copyright notice and this permission notice shall be
  21 // included in all copies or substantial portions of the Software.
  22 //
  23 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  24 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  25 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  26 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  27 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  28 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  29 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  30 //
  31
  32 using System.Globalization;
  33 using System.Security;
  34 using System.Security.Permissions;
  35
  36 namespace System.Drawing.Printing {
  37
  38         [Serializable]
  39         public sealed class PrintingPermission : CodeAccessPermission, IUnrestrictedPermission {
  40
  41                 private const int version = 1;
  42
  43                 private PrintingPermissionLevel _Level;
  44
  45                 public PrintingPermission (PermissionState state)
  46                 {
  47                         if (CheckPermissionState (state, true) == PermissionState.Unrestricted)
  48                                 _Level = PrintingPermissionLevel.AllPrinting;
  49                         else
  50                                 _Level = PrintingPermissionLevel.NoPrinting;
  51                 }
  52
  53                 public PrintingPermission (PrintingPermissionLevel printingLevel)
  54                 {
  55                         Level = printingLevel;
  56                 }
  57
  58                 // properties
  59
  60                 public PrintingPermissionLevel Level{
  61                         get { return _Level; }
  62                         set {
  63                                 if (!Enum.IsDefined (typeof (PrintingPermissionLevel), value)) {
  64                                         string msg = Locale.GetText ("Invalid enum {0}");
  65                                         throw new ArgumentException (String.Format (msg, value), "Level");
  66                                 }
  67                                  _Level = value;
  68                         }
  69                 }
  70
  71                 // methods
  72
  73                 public override IPermission Copy ()
  74                 {
  75                         return new PrintingPermission (this.Level);
  76                 }
  77
  78                 public override void FromXml (SecurityElement esd)
  79                 {
  80                         CheckSecurityElement (esd, "esd", version, version);
  81                         // Note: we do not (yet) care about the return value
  82                         // as we only accept version 1 (min/max values)
  83
  84                         if (IsUnrestricted (esd))
  85                                 _Level = PrintingPermissionLevel.AllPrinting;
  86                         else {
  87                                 string level = esd.Attribute ("Level");
  88                                 if (level != null) {
  89                                         _Level = (PrintingPermissionLevel) Enum.Parse (
  90                                                 typeof (PrintingPermissionLevel), level);
  91                                 }
  92                                 else
  93                                         _Level = PrintingPermissionLevel.NoPrinting;
  94                         }
  95                 }
  96
  97                 public override IPermission Intersect (IPermission target)
  98                 {
  99                         PrintingPermission pp = Cast (target);
 100                         if ((pp == null) || IsEmpty () || pp.IsEmpty ())
 101                                 return null;
 102
 103                         PrintingPermissionLevel level = (_Level <= pp.Level) ? _Level : pp.Level;
 104                         return new PrintingPermission (level);
 105                 }
 106
 107                 public override bool IsSubsetOf (IPermission target)
 108                 {
 109                         PrintingPermission pp = Cast (target);
 110                         if (pp == null)
 111                                 return IsEmpty ();
 112
 113                         return (_Level <= pp.Level);
 114                 }
 115
 116                 public bool IsUnrestricted ()
 117                 {
 118                         return (_Level == PrintingPermissionLevel.AllPrinting);
 119                 }
 120
 121                 public override SecurityElement ToXml ()
 122                 {
 123                         SecurityElement se = Element (version);
 124                         if (IsUnrestricted ())
 125                                 se.AddAttribute ("Unrestricted", "true");
 126                         else
 127                                 se.AddAttribute ("Level", _Level.ToString ());
 128                         return se;
 129                 }
 130
 131                 public override IPermission Union (IPermission target)
 132                 {
 133                         PrintingPermission pp = Cast (target);
 134                         if (pp == null)
 135                                 return new PrintingPermission (_Level);
 136                         if (IsUnrestricted () || pp.IsUnrestricted ())
 137                                 return new PrintingPermission (PermissionState.Unrestricted);
 138                         if (IsEmpty () && pp.IsEmpty ())
 139                                 return null;
 140
 141                         PrintingPermissionLevel level = (_Level > pp.Level) ? _Level : pp.Level;
 142                         return new PrintingPermission (level);
 143                 }
 144
 145                 // Internal helpers methods
 146
 147                 private bool IsEmpty ()
 148                 {
 149                         return (_Level == PrintingPermissionLevel.NoPrinting);
 150                 }
 151
 152                 private PrintingPermission Cast (IPermission target)
 153                 {
 154                         if (target == null)
 155                                 return null;
 156
 157                         PrintingPermission pp = (target as PrintingPermission);
 158                         if (pp == null) {
 159                                 ThrowInvalidPermission (target, typeof (PrintingPermission));
 160                         }
 161
 162                         return pp;
 163                 }
 164
 165                 // NOTE: The following static methods should be moved out to a (static?) class
 166                 // if (ever) System.Drawing.dll gets more than one permission in it's assembly.
 167
 168                 // snippet moved from FileIOPermission (nickd) to be reused in all derived classes
 169                 internal SecurityElement Element (int version)
 170                 {
 171                         SecurityElement se = new SecurityElement ("IPermission");
 172                         Type type = this.GetType ();
 173                         se.AddAttribute ("class", type.FullName + ", " + type.Assembly.ToString ().Replace ('\"', '\''));
 174                         se.AddAttribute ("version", version.ToString ());
 175                         return se;
 176                 }
 177
 178                 internal static PermissionState CheckPermissionState (PermissionState state, bool allowUnrestricted)
 179                 {
 180                         string msg;
 181                         switch (state) {
 182                         case PermissionState.None:
 183                                 break;
 184                         case PermissionState.Unrestricted:
 185                                 if (!allowUnrestricted) {
 186                                         msg = Locale.GetText ("Unrestricted isn't not allowed for identity permissions.");
 187                                         throw new ArgumentException (msg, "state");
 188                                 }
 189                                 break;
 190                         default:
 191                                 msg = String.Format (Locale.GetText ("Invalid enum {0}"), state);
 192                                 throw new ArgumentException (msg, "state");
 193                         }
 194                         return state;
 195                 }
 196
 197                 // logic isn't identical to CodeAccessPermission.CheckSecurityElement - see unit tests
 198                 internal static int CheckSecurityElement (SecurityElement se, string parameterName, int minimumVersion, int maximumVersion)
 199                 {
 200                         if (se == null)
 201                                 throw new ArgumentNullException (parameterName);
 202
 203                         if (se.Attribute ("class") == null) {
 204                                 string msg = Locale.GetText ("Missing 'class' attribute.");
 205                                 throw new ArgumentException (msg, parameterName);
 206                         }
 207
 208                         // we assume minimum version if no version number is supplied
 209                         int version = minimumVersion;
 210                         string v = se.Attribute ("version");
 211                         if (v != null) {
 212                                 try {
 213                                         version = Int32.Parse (v);
 214                                 }
 215                                 catch (Exception e) {
 216                                         string msg = Locale.GetText ("Couldn't parse version from '{0}'.");
 217                                         msg = String.Format (msg, v);
 218                                         throw new ArgumentException (msg, parameterName, e);
 219                                 }
 220                         }
 221
 222                         if ((version < minimumVersion) || (version > maximumVersion)) {
 223                                 string msg = Locale.GetText ("Unknown version '{0}', expected versions between ['{1}','{2}'].");
 224                                 msg = String.Format (msg, version, minimumVersion, maximumVersion);
 225                                 throw new ArgumentException (msg, parameterName);
 226                         }
 227                         return version;
 228                 }
 229
 230                 // must be called after CheckSecurityElement (i.e. se != null)
 231                 internal static bool IsUnrestricted (SecurityElement se)
 232                 {
 233                         string value = se.Attribute ("Unrestricted");
 234                         if (value == null)
 235                                 return false;
 236                         return (String.Compare (value, Boolean.TrueString, true, CultureInfo.InvariantCulture) == 0);
 237                 }
 238
 239                 internal static void ThrowInvalidPermission (IPermission target, Type expected)
 240                 {
 241                         string msg = Locale.GetText ("Invalid permission type '{0}', expected type '{1}'.");
 242                         msg = String.Format (msg, target.GetType (), expected);
 243                         throw new ArgumentException (msg, "target");
 244                 }
 245         }
 246 }