mcs/class/corlib/System.Security.Policy/PolicyStatement.cs

   1 //\r
   2 // System.Security.Policy.PolicyStatement\r
   3 //\r
   4 // Authors:\r
   5 //      Dan Lewis (dihlewis@yahoo.co.uk)\r
   6 //      Sebastien Pouliot  <sebastien@ximian.com>
   7 //\r
   8 // (C) 2002\r
   9 // Copyright (C) 2004-2005 Novell, Inc (http://www.novell.com)
  10 //
  11 // Permission is hereby granted, free of charge, to any person obtaining
  12 // a copy of this software and associated documentation files (the
  13 // "Software"), to deal in the Software without restriction, including
  14 // without limitation the rights to use, copy, modify, merge, publish,
  15 // distribute, sublicense, and/or sell copies of the Software, and to
  16 // permit persons to whom the Software is furnished to do so, subject to
  17 // the following conditions:
  18 //
  19 // The above copyright notice and this permission notice shall be
  20 // included in all copies or substantial portions of the Software.
  21 //
  22 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  23 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  24 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  25 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  26 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  27 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  28 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  29 //
  30 \r
  31 using System.Runtime.InteropServices;
  32 using System.Security.Permissions;\r
  33 \r
  34 namespace System.Security.Policy {\r
  35 \r
  36         [Serializable]\r
  37 #if NET_2_0
  38         [ComVisible (true)]
  39 #endif
  40         public sealed class PolicyStatement : ISecurityEncodable, ISecurityPolicyEncodable {
  41
  42                 private PermissionSet perms;\r
  43                 private PolicyStatementAttribute attrs;\r
  44 \r
  45                 public PolicyStatement (PermissionSet perms) :
  46                         this (perms, PolicyStatementAttribute.Nothing)\r
  47                 {
  48                 }\r
  49 \r
  50                 public PolicyStatement (PermissionSet perms, PolicyStatementAttribute attrs)
  51                 {\r
  52                         if (perms != null) {\r
  53                                 this.perms = perms.Copy ();
  54                                 this.perms.SetReadOnly (true);
  55                         }\r
  56                         this.attrs = attrs;\r
  57                 }\r
  58                 \r
  59                 public PermissionSet PermissionSet {\r
  60                         get {
  61                                 if (perms == null) {
  62                                         perms = new PermissionSet (PermissionState.None);
  63                                         perms.SetReadOnly (true);
  64                                 }
  65                                 return perms;
  66                         }\r
  67                         set { perms = value; }\r
  68                 }\r
  69                 \r
  70                 public PolicyStatementAttribute Attributes {\r
  71                         get { return attrs; }\r
  72                         set {
  73                                 // note: yes it's a flag but all possible values have a corresponding name
  74                                 switch (value) {
  75                                 case PolicyStatementAttribute.Nothing:
  76                                 case PolicyStatementAttribute.Exclusive:
  77                                 case PolicyStatementAttribute.LevelFinal:
  78                                 case PolicyStatementAttribute.All:
  79                                         attrs = value;
  80                                         break;
  81                                 default:
  82                                         string msg = Locale.GetText ("Invalid value for {0}.");
  83                                         throw new ArgumentException (String.Format (msg, "PolicyStatementAttribute"));
  84                                 }
  85                         }\r
  86                 }\r
  87 \r
  88                 public string AttributeString {\r
  89                         get {
  90                                 switch (attrs) {
  91                                 case PolicyStatementAttribute.Exclusive:
  92                                         return "Exclusive";
  93                                 case PolicyStatementAttribute.LevelFinal:
  94                                         return "LevelFinal";
  95                                 case PolicyStatementAttribute.All:
  96                                         return "Exclusive LevelFinal";
  97                                 default:
  98                                         return String.Empty;
  99                                 }
 100                         }\r
 101                 }\r
 102 \r
 103                 public PolicyStatement Copy ()\r
 104                 {\r
 105                         return new PolicyStatement (perms, attrs);\r
 106                 }\r
 107 \r
 108                 // ISecurityEncodable\r
 109 \r
 110                 public void FromXml (SecurityElement e)\r
 111                 {\r
 112                         FromXml (e, null);\r
 113                 }\r
 114 \r
 115                 public void FromXml (SecurityElement e, PolicyLevel level)\r
 116                 {
 117                         if (e == null)
 118                                 throw new ArgumentNullException ("e");
 119                         if (e.Tag != "PolicyStatement")
 120                                 throw new ArgumentException (Locale.GetText ("Invalid tag."));
 121 \r
 122 \r
 123                         string attributes = e.Attribute ("Attributes");\r
 124                         if (attributes != null) {\r
 125                                 attrs = (PolicyStatementAttribute) Enum.Parse (\r
 126                                         typeof (PolicyStatementAttribute), attributes);\r
 127                         }
 128 \r
 129                         SecurityElement permissions = e.SearchForChildByTag ("PermissionSet");\r
 130                         PermissionSet.FromXml (permissions);\r
 131                 }\r
 132                 \r
 133                 public SecurityElement ToXml ()\r
 134                 {\r
 135                         return ToXml (null);\r
 136                 }\r
 137 \r
 138                 public SecurityElement ToXml (PolicyLevel level)\r
 139                 {\r
 140                         SecurityElement element = new SecurityElement ("PolicyStatement");\r
 141                         element.AddAttribute ("version", "1");\r
 142 \r
 143                         if (attrs != PolicyStatementAttribute.Nothing)\r
 144                                 element.AddAttribute ("Attributes", attrs.ToString ());\r
 145                         \r
 146                         element.AddChild (PermissionSet.ToXml ());\r
 147 \r
 148                         return element;\r
 149                 }
 150
 151 #if NET_2_0
 152                 [ComVisible (false)]
 153                 public override bool Equals (object obj)
 154                 {
 155                         if (obj == null)
 156                                 return false;
 157                         PolicyStatement ps = (obj as PolicyStatement);
 158                         if (ps == null)
 159                                 return false;
 160
 161                         return (PermissionSet.Equals (obj) && (attrs == ps.attrs));
 162                 }
 163
 164                 [ComVisible (false)]
 165                 public override int GetHashCode ()
 166                 {
 167                         // return same hash code if two PolicyStatement are equals
 168                         return (PermissionSet.GetHashCode () ^ (int) attrs);
 169                 }
 170 #endif
 171
 172                 internal static PolicyStatement Empty ()
 173                 {
 174                         return new PolicyStatement (new PermissionSet (PermissionState.None));
 175                 }
 176         }\r
 177 }\r