Experiments/Attic/Security/Castle.Services.Security/CustomPermission.cs

   1 // Copyright 2004-2008 Castle Project - http://www.castleproject.org/
   2 //
   3 // Licensed under the Apache License, Version 2.0 (the "License");
   4 // you may not use this file except in compliance with the License.
   5 // You may obtain a copy of the License at
   6 //
   7 //     http://www.apache.org/licenses/LICENSE-2.0
   8 //
   9 // Unless required by applicable law or agreed to in writing, software
  10 // distributed under the License is distributed on an "AS IS" BASIS,
  11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12 // See the License for the specific language governing permissions and
  13 // limitations under the License.
  14
  15 namespace Castle.Services.Security
  16 {
  17         using System;
  18         using System.Security;
  19         using System.Security.Permissions;
  20         using System.Security.Principal;
  21         using System.Threading;
  22
  23         [Serializable]
  24         public sealed class CustomPermission : IPermission, ISecurityEncodable
  25         {
  26                 private string permissionName;
  27
  28                 public CustomPermission(String permissionName)
  29                 {
  30                         this.permissionName = permissionName;
  31                 }
  32
  33                 public CustomPermission(PermissionState state)
  34                 {
  35                 }
  36
  37                 #region IPermission implementation
  38
  39                 public IPermission Copy()
  40                 {
  41                         return new CustomPermission(permissionName);
  42                 }
  43
  44                 public IPermission Intersect(IPermission target)
  45                 {
  46                         if (target == null)
  47                         {
  48                                 return null;
  49                         }
  50
  51                         CustomPermission other = target as CustomPermission;
  52
  53                         if (other == null)
  54                         {
  55                                 throw new ArgumentException("Wrong type specified. Expecting CustomPermission", "target");
  56                         }
  57
  58                         if (other.permissionName.Equals(permissionName))
  59                         {
  60                                 return new CustomPermission(permissionName);
  61                         }
  62
  63                         return null;
  64                 }
  65
  66                 public IPermission Union(IPermission target)
  67                 {
  68                         return Copy();
  69                 }
  70
  71                 public bool IsSubsetOf(IPermission target)
  72                 {
  73                         if (target == null)
  74                         {
  75                                 return false;
  76                         }
  77
  78                         CustomPermission other = target as CustomPermission;
  79
  80                         if (other == null)
  81                         {
  82                                 throw new ArgumentException("Wrong type specified. Expecting CustomPermission", "target");
  83                         }
  84
  85                         return (other.permissionName.Equals(permissionName));
  86                 }
  87
  88                 public void Demand()
  89                 {
  90                         IPrincipal principal = Thread.CurrentPrincipal;
  91
  92                         IExtendedPrincipal extendedPrincipal = principal as IExtendedPrincipal;
  93
  94                         if (extendedPrincipal == null)
  95                         {
  96                                 throw new SecurityException("The current principal does not implement IExtendedPrincipal");
  97                         }
  98
  99                         if (!extendedPrincipal.HasPermission(permissionName))
 100                         {
 101                                 throw new SecurityException("Current principal does not have permission " + permissionName);
 102                         }
 103                 }
 104
 105                 #endregion
 106
 107                 #region ISecurityEncodable implementation
 108
 109                 public SecurityElement ToXml()
 110                 {
 111                         SecurityElement elem = new SecurityElement("IPermission");
 112
 113                         elem.AddAttribute("class",
 114                                 String.Format("{0}, {1}",
 115                                         typeof(CustomPermission).FullName, typeof(CustomPermission).Assembly.FullName ));
 116                         elem.AddAttribute("version", "1");
 117                         elem.AddAttribute("Unrestricted", "false");
 118
 119                         if (permissionName != null)
 120                         {
 121                                 elem.AddAttribute("permName", permissionName);
 122                         }
 123
 124                         return elem;
 125                 }
 126
 127                 public void FromXml(SecurityElement elem)
 128                 {
 129                         object permName = elem.Attributes["permName"];
 130
 131                         if (permName != null)
 132                         {
 133                                 permissionName = permName.ToString();
 134                         }
 135                 }
 136
 137                 #endregion
 138         }
 139 }