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

   1 //
   2 // System.Security.Policy.PolicyLevel.cs
   3 //
   4 // Authors:
   5 //      Nick Drochak (ndrochak@gol.com)
   6 //      Duncan Mak (duncan@ximian.com)
   7 //      Sebastien Pouliot  <sebastien@ximian.com>
   8 //
   9 // (C) 2001 Nick Drochak
  10 // (C) 2003 Duncan Mak, Ximian Inc.
  11 // Portions (C) 2004 Motus Technologies Inc. (http://www.motus.com)
  12 // Copyright (C) 2004-2005 Novell, Inc (http://www.novell.com)
  13 //
  14 // Permission is hereby granted, free of charge, to any person obtaining
  15 // a copy of this software and associated documentation files (the
  16 // "Software"), to deal in the Software without restriction, including
  17 // without limitation the rights to use, copy, modify, merge, publish,
  18 // distribute, sublicense, and/or sell copies of the Software, and to
  19 // permit persons to whom the Software is furnished to do so, subject to
  20 // the following conditions:
  21 //
  22 // The above copyright notice and this permission notice shall be
  23 // included in all copies or substantial portions of the Software.
  24 //
  25 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  26 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  27 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  28 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  29 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  30 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  31 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  32 //
  33
  34 using System.Collections; // for IList
  35 using System.Globalization;
  36 using System.IO;
  37 using System.Reflection;
  38 using System.Runtime.InteropServices;
  39 using System.Security.Permissions;
  40
  41 using Mono.Xml;
  42
  43 namespace System.Security.Policy {
  44
  45         [Serializable]
  46         [ComVisible (true)]
  47         public sealed class PolicyLevel {
  48
  49                 string label;
  50                 CodeGroup root_code_group;
  51                 private ArrayList full_trust_assemblies;
  52                 private ArrayList named_permission_sets;
  53                 private string _location;
  54                 private PolicyLevelType _type;
  55                 private Hashtable fullNames;
  56                 private SecurityElement xml;
  57
  58                 internal PolicyLevel (string label, PolicyLevelType type)
  59                 {
  60                         this.label = label;
  61                         _type = type;
  62                         full_trust_assemblies = new ArrayList ();
  63                         named_permission_sets = new ArrayList ();
  64                 }
  65
  66                 internal void LoadFromFile (string filename)
  67                 {
  68                         try {
  69                                 // check for policy file
  70                                 if (!File.Exists (filename)) {
  71                                         // if it doesn't exist use the default configuration (like Fx 2.0)
  72                                         // ref: http://blogs.msdn.com/shawnfa/archive/2004/04/21/117833.aspx
  73                                         string defcfg = filename + ".default";
  74                                         if (File.Exists (defcfg)) {
  75                                                 // create policy from default file
  76                                                 File.Copy (defcfg, filename);
  77                                         }
  78                                 }
  79                                 // load security policy configuration
  80                                 if (File.Exists (filename)) {
  81                                         using (StreamReader sr = File.OpenText (filename)) {
  82                                                 xml = FromString (sr.ReadToEnd ());
  83                                         }
  84                                         try {
  85                                                 SecurityManager.ResolvingPolicyLevel = this;
  86                                                 FromXml (xml);
  87                                         }
  88                                         finally {
  89                                                 SecurityManager.ResolvingPolicyLevel = this;
  90                                         }
  91                                 } else {
  92                                         CreateDefaultFullTrustAssemblies ();
  93                                         CreateDefaultNamedPermissionSets ();
  94                                         CreateDefaultLevel (_type);
  95                                         Save ();
  96                                 }
  97                         }
  98                         catch {
  99                                 // this can fail in many ways including...
 100                                 // * can't lookup policy (path discovery);
 101                                 // * can't copy default file to policy
 102                                 // * can't read policy file;
 103                                 // * can't decode policy file
 104                                 // * can't save hardcoded policy to filename
 105                         }
 106                         finally {
 107                                 _location = filename;
 108                         }
 109                 }
 110
 111                 internal void LoadFromString (string xml)
 112                 {
 113                         FromXml (FromString (xml));
 114                 }
 115
 116                 private SecurityElement FromString (string xml)
 117                 {
 118                         SecurityParser parser = new SecurityParser ();
 119                         parser.LoadXml (xml);
 120                         // configuration / mscorlib / security / policy / PolicyLevel
 121                         SecurityElement configuration = parser.ToXml ();
 122                         if (configuration.Tag != "configuration")
 123                                 throw new ArgumentException (Locale.GetText ("missing <configuration> root element"));
 124                         SecurityElement mscorlib = (SecurityElement) configuration.Children [0];
 125                         if (mscorlib.Tag != "mscorlib")
 126                                 throw new ArgumentException (Locale.GetText ("missing <mscorlib> tag"));
 127                         SecurityElement security = (SecurityElement) mscorlib.Children [0];
 128                         if (security.Tag != "security")
 129                                 throw new ArgumentException (Locale.GetText ("missing <security> tag"));
 130                         SecurityElement policy = (SecurityElement) security.Children [0];
 131                         if (policy.Tag != "policy")
 132                                 throw new ArgumentException (Locale.GetText ("missing <policy> tag"));
 133                         SecurityElement policyLevel = (SecurityElement) policy.Children [0];
 134                         return policyLevel;
 135                 }
 136
 137                 // properties
 138
 139                 [Obsolete ("All GACed assemblies are now fully trusted and all permissions now succeed on fully trusted code.")]
 140                 public IList FullTrustAssemblies {
 141                         get { return full_trust_assemblies; }
 142                 }
 143
 144                 public string Label {
 145                         get { return label; }
 146                 }
 147
 148                 public IList NamedPermissionSets {
 149                         get { return named_permission_sets; }
 150                 }
 151
 152                 public CodeGroup RootCodeGroup {
 153                         get { return root_code_group; }
 154                         set {
 155                                 if (value == null)
 156                                         throw new ArgumentNullException ("value");
 157                                 root_code_group = value;
 158                         }
 159                 }
 160
 161                 public string StoreLocation {
 162                         get { return _location; }
 163                 }
 164
 165                 [ComVisible (false)]
 166                 public PolicyLevelType Type {
 167                         get { return _type; }
 168                 }
 169
 170                 // methods
 171
 172                 [Obsolete ("All GACed assemblies are now fully trusted and all permissions now succeed on fully trusted code.")]
 173                 public void AddFullTrustAssembly (StrongName sn)
 174                 {
 175                         if (sn == null)
 176                                 throw new ArgumentNullException ("sn");
 177
 178                         StrongNameMembershipCondition snMC = new StrongNameMembershipCondition(
 179                                 sn.PublicKey, sn.Name, sn.Version);
 180
 181                         AddFullTrustAssembly (snMC);
 182                 }
 183
 184                 [Obsolete ("All GACed assemblies are now fully trusted and all permissions now succeed on fully trusted code.")]
 185                 public void AddFullTrustAssembly (StrongNameMembershipCondition snMC)
 186                 {
 187                         if (snMC == null)
 188                                 throw new ArgumentNullException ("snMC");
 189
 190                         foreach (StrongNameMembershipCondition sn in full_trust_assemblies) {
 191                                 if (sn.Equals (snMC)) {
 192                                         throw new ArgumentException (Locale.GetText ("sn already has full trust."));
 193                                 }
 194                         }
 195                         full_trust_assemblies.Add (snMC);
 196                 }
 197
 198                 public void AddNamedPermissionSet (NamedPermissionSet permSet)
 199                 {
 200                         if (permSet == null)
 201                                 throw new ArgumentNullException ("permSet");
 202
 203                         foreach (NamedPermissionSet n in named_permission_sets) {
 204                                 if (permSet.Name == n.Name) {
 205                                         throw new ArgumentException (
 206                                                 Locale.GetText ("This NamedPermissionSet is the same an existing NamedPermissionSet."));
 207                                 }
 208                         }
 209                         named_permission_sets.Add (permSet.Copy ());
 210                 }
 211
 212                 public NamedPermissionSet ChangeNamedPermissionSet (string name, PermissionSet pSet)
 213                 {
 214                         if (name == null)
 215                                 throw new ArgumentNullException ("name");
 216                         if (pSet == null)
 217                                 throw new ArgumentNullException ("pSet");
 218                         if (DefaultPolicies.ReservedNames.IsReserved (name))
 219                                 throw new ArgumentException (Locale.GetText ("Reserved name"));
 220
 221                         foreach (NamedPermissionSet n in named_permission_sets) {
 222                                 if (name == n.Name) {
 223                                         named_permission_sets.Remove (n);
 224                                         AddNamedPermissionSet (new NamedPermissionSet (name, pSet));
 225                                         return n;
 226                                 }
 227                         }
 228                         throw new ArgumentException (Locale.GetText ("PermissionSet not found"));
 229                 }
 230
 231                 public static PolicyLevel CreateAppDomainLevel ()
 232                 {
 233                         UnionCodeGroup cg = new UnionCodeGroup (new AllMembershipCondition (), new PolicyStatement (DefaultPolicies.FullTrust));
 234                         cg.Name = "All_Code";
 235                         PolicyLevel pl = new PolicyLevel ("AppDomain", PolicyLevelType.AppDomain);
 236                         pl.RootCodeGroup = cg;
 237                         pl.Reset ();
 238                         return pl;
 239                 }
 240
 241
 242                 public void FromXml (SecurityElement e)
 243                 {
 244                         if (e == null)
 245                                 throw new ArgumentNullException ("e");
 246 // MS doesn't throw an exception for this case
 247 //                      if (e.Tag != "PolicyLevel")
 248 //                              throw new ArgumentException (Locale.GetText ("Invalid XML"));
 249
 250                         SecurityElement sc = e.SearchForChildByTag ("SecurityClasses");
 251                         if ((sc != null) && (sc.Children != null) && (sc.Children.Count > 0)) {
 252                                 fullNames = new Hashtable (sc.Children.Count);
 253                                 foreach (SecurityElement se in sc.Children) {
 254                                         fullNames.Add (se.Attributes ["Name"], se.Attributes ["Description"]);
 255                                 }
 256                         }
 257
 258                         SecurityElement fta = e.SearchForChildByTag ("FullTrustAssemblies");
 259                         if ((fta != null) && (fta.Children != null) && (fta.Children.Count > 0)) {
 260                                 full_trust_assemblies.Clear ();
 261                                 foreach (SecurityElement se in fta.Children) {
 262                                         if (se.Tag != "IMembershipCondition")
 263                                                 throw new ArgumentException (Locale.GetText ("Invalid XML"));
 264                                         string className = se.Attribute ("class");
 265                                         if (className.IndexOf ("StrongNameMembershipCondition") < 0)
 266                                                 throw new ArgumentException (Locale.GetText ("Invalid XML - must be StrongNameMembershipCondition"));
 267                                         // we directly use StrongNameMembershipCondition
 268                                         full_trust_assemblies.Add (new StrongNameMembershipCondition (se));
 269                                 }
 270                         }
 271
 272                         SecurityElement cg = e.SearchForChildByTag ("CodeGroup");
 273                         if ((cg != null) && (cg.Children != null) && (cg.Children.Count > 0)) {
 274                                 root_code_group = CodeGroup.CreateFromXml (cg, this);
 275                         } else {
 276                                 throw new ArgumentException (Locale.GetText ("Missing Root CodeGroup"));
 277                         }
 278
 279                         SecurityElement nps = e.SearchForChildByTag ("NamedPermissionSets");
 280                         if ((nps != null) && (nps.Children != null) && (nps.Children.Count > 0)) {
 281                                 named_permission_sets.Clear ();
 282                                 foreach (SecurityElement se in nps.Children) {
 283                                         NamedPermissionSet n = new NamedPermissionSet ();
 284                                         n.Resolver = this;
 285                                         n.FromXml (se);
 286                                         named_permission_sets.Add (n);
 287                                 }
 288                         }
 289                 }
 290
 291                 public NamedPermissionSet GetNamedPermissionSet (string name)
 292                 {
 293                         if (name == null)
 294                                 throw new ArgumentNullException ("name");
 295
 296                         foreach (NamedPermissionSet n in named_permission_sets) {
 297                                 if (n.Name == name)
 298                                         return (NamedPermissionSet) n.Copy ();
 299                         }
 300                         return null;
 301                 }
 302
 303                 public void Recover ()
 304                 {
 305                         if (_location == null) {
 306                                 string msg = Locale.GetText ("Only file based policies may be recovered.");
 307                                 throw new PolicyException (msg);
 308                         }
 309
 310                         string backup = _location + ".backup";
 311                         if (!File.Exists (backup)) {
 312                                 string msg = Locale.GetText ("No policy backup exists.");
 313                                 throw new PolicyException (msg);
 314                         }
 315
 316                         try {
 317                                 File.Copy (backup, _location, true);
 318                         }
 319                         catch (Exception e) {
 320                                 string msg = Locale.GetText ("Couldn't replace the policy file with it's backup.");
 321                                 throw new PolicyException (msg, e);
 322                         }
 323                 }
 324
 325                 [Obsolete ("All GACed assemblies are now fully trusted and all permissions now succeed on fully trusted code.")]
 326                 public void RemoveFullTrustAssembly (StrongName sn)
 327                 {
 328                         if (sn == null)
 329                                 throw new ArgumentNullException ("sn");
 330
 331                         StrongNameMembershipCondition s = new StrongNameMembershipCondition (sn.PublicKey, sn.Name, sn.Version);
 332                         RemoveFullTrustAssembly (s);
 333                 }
 334
 335                 [Obsolete ("All GACed assemblies are now fully trusted and all permissions now succeed on fully trusted code.")]
 336                 public void RemoveFullTrustAssembly (StrongNameMembershipCondition snMC)
 337                 {
 338                         if (snMC == null)
 339                                 throw new ArgumentNullException ("snMC");
 340
 341                         if (((IList) full_trust_assemblies).Contains (snMC))
 342                                 ((IList) full_trust_assemblies).Remove (snMC);
 343
 344                         else
 345                                 throw new ArgumentException (
 346                                         Locale.GetText ("sn does not have full trust."));
 347                 }
 348
 349                 public NamedPermissionSet RemoveNamedPermissionSet (NamedPermissionSet permSet)
 350                 {
 351                         if (permSet == null)
 352                                 throw new ArgumentNullException ("permSet");
 353
 354                         return RemoveNamedPermissionSet (permSet.Name);
 355                 }
 356
 357                 public NamedPermissionSet RemoveNamedPermissionSet (string name)
 358                 {
 359                         if (name == null)
 360                                 throw new ArgumentNullException ("name");
 361                         if (DefaultPolicies.ReservedNames.IsReserved (name))
 362                                 throw new ArgumentException (Locale.GetText ("Reserved name"));
 363
 364                         foreach (NamedPermissionSet nps in named_permission_sets) {
 365                                 if (name == nps.Name) {
 366                                         named_permission_sets.Remove (nps);
 367                                         return nps;
 368                                 }
 369                         }
 370                         string msg = String.Format (Locale.GetText ("Name '{0}' cannot be found."), name);
 371                         throw new ArgumentException (msg, "name");
 372                 }
 373
 374                 public void Reset ()
 375                 {
 376                         if (fullNames != null)
 377                                 fullNames.Clear ();
 378
 379                         if (_type != PolicyLevelType.AppDomain) {
 380                                 full_trust_assemblies.Clear ();
 381                                 named_permission_sets.Clear ();
 382
 383                                 // because the policy doesn't exist LoadFromFile will try to
 384                                 // 1. use the .default file if existing (like Fx 2.0 does); or
 385                                 // 2. use the hard-coded default values
 386                                 // and recreate a policy file
 387                                 if ((_location != null) && (File.Exists (_location))) {
 388                                         try {
 389                                                 File.Delete (_location);
 390                                         }
 391                                         catch {}
 392                                 }
 393                                 LoadFromFile (_location);
 394                         } else {
 395                                 CreateDefaultFullTrustAssemblies ();
 396                                 CreateDefaultNamedPermissionSets ();
 397                         }
 398                 }
 399
 400                 public PolicyStatement Resolve (Evidence evidence)
 401                 {
 402                         if (evidence == null)
 403                                 throw new ArgumentNullException ("evidence");
 404
 405                         PolicyStatement ps = root_code_group.Resolve (evidence);
 406                         return ((ps != null) ? ps : PolicyStatement.Empty ());
 407                 }
 408
 409                 public CodeGroup ResolveMatchingCodeGroups (Evidence evidence)
 410                 {
 411                         if (evidence == null)
 412                                 throw new ArgumentNullException ("evidence");
 413
 414                         CodeGroup cg = root_code_group.ResolveMatchingCodeGroups (evidence);
 415                         return ((cg != null) ? cg : null);
 416                 }
 417
 418                 public SecurityElement ToXml ()
 419                 {
 420                         Hashtable fullNames = new Hashtable ();
 421                         // only StrongNameMembershipCondition so no need to loop
 422                         if (full_trust_assemblies.Count > 0) {
 423                                 if (!fullNames.Contains ("StrongNameMembershipCondition")) {
 424                                         fullNames.Add ("StrongNameMembershipCondition", typeof (StrongNameMembershipCondition).FullName);
 425                                 }
 426                         }
 427
 428                         SecurityElement namedPSs = new SecurityElement ("NamedPermissionSets");
 429                         foreach (NamedPermissionSet nps in named_permission_sets) {
 430                                 SecurityElement se = nps.ToXml ();
 431                                 object objectClass = se.Attributes ["class"];
 432                                 if (!fullNames.Contains (objectClass)) {
 433                                         fullNames.Add (objectClass, nps.GetType ().FullName);
 434                                 }
 435                                 namedPSs.AddChild (se);
 436                         }
 437
 438                         SecurityElement fta = new SecurityElement ("FullTrustAssemblies");
 439                         foreach (StrongNameMembershipCondition snmc in full_trust_assemblies) {
 440                                 fta.AddChild (snmc.ToXml (this));
 441                         }
 442
 443                         SecurityElement security_classes = new SecurityElement ("SecurityClasses");
 444                         if (fullNames.Count > 0) {
 445                                 foreach (DictionaryEntry de in fullNames) {
 446                                         SecurityElement sc = new SecurityElement ("SecurityClass");
 447                                         sc.AddAttribute ("Name", (string)de.Key);
 448                                         sc.AddAttribute ("Description", (string)de.Value);
 449                                         security_classes.AddChild (sc);
 450                                 }
 451                         }
 452
 453                         SecurityElement element = new SecurityElement (typeof (System.Security.Policy.PolicyLevel).Name);
 454                         element.AddAttribute ("version", "1");
 455                         element.AddChild (security_classes);
 456                         element.AddChild (namedPSs);
 457                         if (root_code_group != null) {
 458                                 element.AddChild (root_code_group.ToXml (this));
 459                         }
 460                         element.AddChild (fta);
 461
 462                         return element;
 463                 }
 464
 465                 // internal stuff
 466
 467                 // NOTE: Callers are expected to check for ControlPolicy
 468                 internal void Save ()
 469                 {
 470                         if (_type == PolicyLevelType.AppDomain) {
 471                                 throw new PolicyException (Locale.GetText (
 472                                         "Can't save AppDomain PolicyLevel"));
 473                         }
 474
 475                         if (_location != null) {
 476                                 try {
 477                                         if (File.Exists (_location)) {
 478                                                 File.Copy (_location, _location + ".backup", true);
 479                                         }
 480                                 }
 481                                 catch (Exception) {
 482                                 }
 483                                 finally {
 484                                         using (StreamWriter sw = new StreamWriter (_location)) {
 485                                                 sw.Write (ToXml ().ToString ());
 486                                                 sw.Close ();
 487                                         }
 488                                 }
 489                         }
 490                 }
 491
 492                 // Hardcode defaults in case
 493                 // (a) the specified policy file doesn't exists; and
 494                 // (b) no corresponding default policy file exists
 495                 internal void CreateDefaultLevel (PolicyLevelType type)
 496                 {
 497                         PolicyStatement psu = new PolicyStatement (DefaultPolicies.FullTrust);
 498
 499                         switch (type) {
 500                         case PolicyLevelType.Machine:
 501                                 // by default all stuff is in the machine policy...
 502                                 PolicyStatement psn = new PolicyStatement (DefaultPolicies.Nothing);
 503                                 root_code_group = new UnionCodeGroup (new AllMembershipCondition (), psn);
 504                                 root_code_group.Name = "All_Code";
 505
 506                                 UnionCodeGroup myComputerZone = new UnionCodeGroup (new ZoneMembershipCondition (SecurityZone.MyComputer), psu);
 507                                 myComputerZone.Name = "My_Computer_Zone";
 508                                 // TODO: strongname code group for ECMA and MS keys
 509                                 root_code_group.AddChild (myComputerZone);
 510
 511                                 UnionCodeGroup localIntranetZone = new UnionCodeGroup (new ZoneMembershipCondition (SecurityZone.Intranet),
 512                                         new PolicyStatement (DefaultPolicies.LocalIntranet));
 513                                 localIntranetZone.Name = "LocalIntranet_Zone";
 514                                 // TODO: same site / same directory
 515                                 root_code_group.AddChild (localIntranetZone);
 516
 517                                 PolicyStatement psi = new PolicyStatement (DefaultPolicies.Internet);
 518                                 UnionCodeGroup internetZone = new UnionCodeGroup (new ZoneMembershipCondition (SecurityZone.Internet), psi);
 519                                 internetZone.Name = "Internet_Zone";
 520                                 // TODO: same site
 521                                 root_code_group.AddChild (internetZone);
 522
 523                                 UnionCodeGroup restrictedZone = new UnionCodeGroup (new ZoneMembershipCondition (SecurityZone.Untrusted), psn);
 524                                 restrictedZone.Name = "Restricted_Zone";
 525                                 root_code_group.AddChild (restrictedZone);
 526
 527                                 UnionCodeGroup trustedZone = new UnionCodeGroup (new ZoneMembershipCondition (SecurityZone.Trusted), psi);
 528                                 trustedZone.Name = "Trusted_Zone";
 529                                 // TODO: same site
 530                                 root_code_group.AddChild (trustedZone);
 531                                 break;
 532                         case PolicyLevelType.User:
 533                         case PolicyLevelType.Enterprise:
 534                         case PolicyLevelType.AppDomain:
 535                                 // while the other policies don't restrict anything
 536                                 root_code_group = new UnionCodeGroup (new AllMembershipCondition (), psu);
 537                                 root_code_group.Name = "All_Code";
 538                                 break;
 539                         }
 540                 }
 541
 542                 internal void CreateDefaultFullTrustAssemblies ()
 543                 {
 544                         // (default) assemblies that are fully trusted during policy resolution
 545                         full_trust_assemblies.Clear ();
 546                         full_trust_assemblies.Add (DefaultPolicies.FullTrustMembership ("mscorlib", DefaultPolicies.Key.Ecma));
 547                         full_trust_assemblies.Add (DefaultPolicies.FullTrustMembership ("System", DefaultPolicies.Key.Ecma));
 548                         full_trust_assemblies.Add (DefaultPolicies.FullTrustMembership ("System.Data", DefaultPolicies.Key.Ecma));
 549                         full_trust_assemblies.Add (DefaultPolicies.FullTrustMembership ("System.DirectoryServices", DefaultPolicies.Key.MsFinal));
 550                         full_trust_assemblies.Add (DefaultPolicies.FullTrustMembership ("System.Drawing", DefaultPolicies.Key.MsFinal));
 551                         full_trust_assemblies.Add (DefaultPolicies.FullTrustMembership ("System.Messaging", DefaultPolicies.Key.MsFinal));
 552                         full_trust_assemblies.Add (DefaultPolicies.FullTrustMembership ("System.ServiceProcess", DefaultPolicies.Key.MsFinal));
 553                 }
 554
 555                 internal void CreateDefaultNamedPermissionSets ()
 556                 {
 557                         named_permission_sets.Clear ();
 558                         try {
 559                                 SecurityManager.ResolvingPolicyLevel = this;
 560                                 named_permission_sets.Add (DefaultPolicies.LocalIntranet);
 561                                 named_permission_sets.Add (DefaultPolicies.Internet);
 562                                 named_permission_sets.Add (DefaultPolicies.SkipVerification);
 563                                 named_permission_sets.Add (DefaultPolicies.Execution);
 564                                 named_permission_sets.Add (DefaultPolicies.Nothing);
 565                                 named_permission_sets.Add (DefaultPolicies.Everything);
 566                                 named_permission_sets.Add (DefaultPolicies.FullTrust);
 567                         }
 568                         finally {
 569                                 SecurityManager.ResolvingPolicyLevel = null;
 570                         }
 571                 }
 572
 573                 internal string ResolveClassName (string className)
 574                 {
 575                         if (fullNames != null) {
 576                                 object name = fullNames [className];
 577                                 if (name != null)
 578                                         return (string) name;
 579                         }
 580                         return className;
 581                 }
 582
 583                 internal bool IsFullTrustAssembly (Assembly a)
 584                 {
 585                         AssemblyName an = a.GetName ();
 586                         StrongNamePublicKeyBlob snpkb = new StrongNamePublicKeyBlob (an.GetPublicKey ());
 587                         StrongNameMembershipCondition snMC = new StrongNameMembershipCondition (snpkb, an.Name, an.Version);
 588                         foreach (StrongNameMembershipCondition sn in full_trust_assemblies) {
 589                                 if (sn.Equals (snMC)) {
 590                                         return true;
 591                                 }
 592                         }
 593                         return false;
 594                 }
 595         }
 596 }