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 #if NET_2_0
  47         [ComVisible (true)]
  48 #endif
  49         public sealed class PolicyLevel {
  50
  51                 string label;
  52                 CodeGroup root_code_group;
  53                 private ArrayList full_trust_assemblies;
  54                 private ArrayList named_permission_sets;
  55                 private string _location;
  56                 private PolicyLevelType _type;
  57                 private Hashtable fullNames;
  58                 private bool loaded;
  59                 private SecurityElement xml;
  60
  61                 internal PolicyLevel (string label, PolicyLevelType type)
  62                 {
  63                         this.label = label;
  64                         _type = type;
  65                         full_trust_assemblies = new ArrayList ();
  66                         named_permission_sets = new ArrayList ();
  67                 }
  68
  69                 internal void LoadFromFile (string filename)
  70                 {
  71                         try {
  72                                 loaded = false;
  73                                 // check for policy file
  74                                 if (!File.Exists (filename)) {
  75                                         // if it doesn't exist use the default configuration (like Fx 2.0)
  76                                         // ref: http://blogs.msdn.com/shawnfa/archive/2004/04/21/117833.aspx
  77                                         string defcfg = filename + ".default";
  78                                         if (File.Exists (defcfg)) {
  79                                                 // create policy from default file
  80                                                 File.Copy (defcfg, filename);
  81                                         }
  82                                 }
  83                                 // load security policy configuration
  84                                 if (File.Exists (filename)) {
  85                                         using (StreamReader sr = File.OpenText (filename)) {
  86                                                 xml = FromString (sr.ReadToEnd ());
  87                                                 FromXml1 (xml);
  88                                         }
  89                                         loaded = true;
  90                                 } else {
  91                                         CreateDefaultLevel (_type);
  92                                 }
  93                         }
  94                         catch {
  95                                 // this can fail in many ways including...
  96                                 // * can't lookup policy (path discovery);
  97                                 // * can't copy default file to policy
  98                                 // * can't read policy file;
  99                                 // * can't decode policy file
 100                                 if (!loaded)
 101                                         CreateDefaultLevel (_type);
 102                         }
 103                         finally {
 104                                 _location = filename;
 105                         }
 106                 }
 107
 108                 internal void Initialize ()
 109                 {
 110                         if (loaded) {
 111                                 FromXml2 (xml);
 112                         } else {
 113                                 CreateDefaultNamedPermissionSets ();
 114                                 try {
 115                                         Save ();
 116                                 }
 117                                 catch {
 118                                         // this can fail in many ways including...
 119                                         // * can't save hardcoded policy to filename
 120                                 }
 121                         }
 122                 }
 123
 124                 internal void LoadFromString (string xml)
 125                 {
 126                         FromXml (FromString (xml));
 127                 }
 128
 129                 private SecurityElement FromString (string xml)
 130                 {
 131                         SecurityParser parser = new SecurityParser ();
 132                         parser.LoadXml (xml);
 133                         // configuration / mscorlib / security / policy / PolicyLevel
 134                         SecurityElement configuration = parser.ToXml ();
 135                         if (configuration.Tag != "configuration")
 136                                 throw new ArgumentException (Locale.GetText ("missing <configuration> root element"));
 137                         SecurityElement mscorlib = (SecurityElement) configuration.Children [0];
 138                         if (mscorlib.Tag != "mscorlib")
 139                                 throw new ArgumentException (Locale.GetText ("missing <mscorlib> tag"));
 140                         SecurityElement security = (SecurityElement) mscorlib.Children [0];
 141                         if (security.Tag != "security")
 142                                 throw new ArgumentException (Locale.GetText ("missing <security> tag"));
 143                         SecurityElement policy = (SecurityElement) security.Children [0];
 144                         if (policy.Tag != "policy")
 145                                 throw new ArgumentException (Locale.GetText ("missing <policy> tag"));
 146                         SecurityElement policyLevel = (SecurityElement) policy.Children [0];
 147                         return policyLevel;
 148                 }
 149
 150                 // properties
 151
 152                 public IList FullTrustAssemblies {
 153                         get { return full_trust_assemblies; }
 154                 }
 155
 156                 public string Label {
 157                         get { return label; }
 158                 }
 159
 160                 public IList NamedPermissionSets {
 161                         get { return named_permission_sets; }
 162                 }
 163
 164                 public CodeGroup RootCodeGroup {
 165                         get { return root_code_group; }
 166                         set {
 167                                 if (value == null)
 168                                         throw new ArgumentNullException ("value");
 169                                 root_code_group = value;
 170                         }
 171                 }
 172
 173                 public string StoreLocation {
 174                         get { return _location; }
 175                 }
 176
 177 #if NET_2_0
 178                 [ComVisible (false)]
 179                 public PolicyLevelType Type {
 180                         get { return _type; }
 181                 }
 182 #endif
 183
 184                 // methods
 185
 186                 public void AddFullTrustAssembly (StrongName sn)
 187                 {
 188                         if (sn == null)
 189                                 throw new ArgumentNullException ("sn");
 190
 191                         StrongNameMembershipCondition snMC = new StrongNameMembershipCondition(
 192                                 sn.PublicKey, sn.Name, sn.Version);
 193
 194                         AddFullTrustAssembly (snMC);
 195                 }
 196
 197                 public void AddFullTrustAssembly (StrongNameMembershipCondition snMC)
 198                 {
 199                         if (snMC == null)
 200                                 throw new ArgumentNullException ("snMC");
 201
 202                         foreach (StrongNameMembershipCondition sn in full_trust_assemblies) {
 203                                 if (sn.Equals (snMC)) {
 204                                         throw new ArgumentException (Locale.GetText ("sn already has full trust."));
 205                                 }
 206                         }
 207                         full_trust_assemblies.Add (snMC);
 208                 }
 209
 210                 public void AddNamedPermissionSet (NamedPermissionSet permSet)
 211                 {
 212                         if (permSet == null)
 213                                 throw new ArgumentNullException ("permSet");
 214
 215                         foreach (NamedPermissionSet n in named_permission_sets) {
 216                                 if (permSet.Name == n.Name) {
 217                                         throw new ArgumentException (
 218                                                 Locale.GetText ("This NamedPermissionSet is the same an existing NamedPermissionSet."));
 219                                 }
 220                         }
 221                         named_permission_sets.Add (permSet.Copy ());
 222                 }
 223
 224                 public NamedPermissionSet ChangeNamedPermissionSet (string name, PermissionSet pSet)
 225                 {
 226                         if (name == null)
 227                                 throw new ArgumentNullException ("name");
 228                         if (pSet == null)
 229                                 throw new ArgumentNullException ("pSet");
 230                         if (DefaultPolicies.ReservedNames.IsReserved (name))
 231                                 throw new ArgumentException (Locale.GetText ("Reserved name"));
 232
 233                         foreach (NamedPermissionSet n in named_permission_sets) {
 234                                 if (name == n.Name) {
 235                                         named_permission_sets.Remove (n);
 236                                         AddNamedPermissionSet (new NamedPermissionSet (name, pSet));
 237                                         return n;
 238                                 }
 239                         }
 240                         throw new ArgumentException (Locale.GetText ("PermissionSet not found"));
 241                 }
 242
 243                 public static PolicyLevel CreateAppDomainLevel ()
 244                 {
 245                         NamedPermissionSet fullTrust = new NamedPermissionSet ("FullTrust", PermissionState.Unrestricted);
 246                         UnionCodeGroup cg = new UnionCodeGroup (new AllMembershipCondition (), new PolicyStatement (fullTrust));
 247                         cg.Name = "All_Code";
 248                         PolicyLevel pl = new PolicyLevel ("AppDomain", PolicyLevelType.AppDomain);
 249                         pl.RootCodeGroup = cg;
 250                         pl.Reset ();
 251                         return pl;
 252                 }
 253
 254
 255                 public void FromXml (SecurityElement e)
 256                 {
 257                         if (e == null)
 258                                 throw new ArgumentNullException ("e");
 259 // MS doesn't throw an exception for this case
 260 //                      if (e.Tag != "PolicyLevel")
 261 //                              throw new ArgumentException (Locale.GetText ("Invalid XML"));
 262
 263                         FromXml1 (e);
 264                         FromXml2 (e);
 265                 }
 266
 267                 internal void FromXml1 (SecurityElement e)
 268                 {
 269                         SecurityElement sc = e.SearchForChildByTag ("SecurityClasses");
 270                         if ((sc != null) && (sc.Children != null) && (sc.Children.Count > 0)) {
 271                                 fullNames = new Hashtable (sc.Children.Count);
 272                                 foreach (SecurityElement se in sc.Children) {
 273                                         fullNames.Add (se.Attributes ["Name"], se.Attributes ["Description"]);
 274                                 }
 275                         }
 276
 277                         SecurityElement fta = e.SearchForChildByTag ("FullTrustAssemblies");
 278                         if ((fta != null) && (fta.Children != null) && (fta.Children.Count > 0)) {
 279                                 full_trust_assemblies.Clear ();
 280                                 foreach (SecurityElement se in fta.Children) {
 281                                         if (se.Tag != "IMembershipCondition")
 282                                                 throw new ArgumentException (Locale.GetText ("Invalid XML"));
 283                                         string className = se.Attribute ("class");
 284                                         if (className.IndexOf ("StrongNameMembershipCondition") < 0)
 285                                                 throw new ArgumentException (Locale.GetText ("Invalid XML - must be StrongNameMembershipCondition"));
 286                                         // we directly use StrongNameMembershipCondition
 287                                         full_trust_assemblies.Add (new StrongNameMembershipCondition (se));
 288                                 }
 289                         }
 290
 291                         SecurityElement cg = e.SearchForChildByTag ("CodeGroup");
 292                         if ((cg != null) && (cg.Children != null) && (cg.Children.Count > 0)) {
 293                                 root_code_group = CodeGroup.CreateFromXml (cg, this);
 294                         }
 295                         else
 296                                 throw new ArgumentException (Locale.GetText ("Missing Root CodeGroup"));
 297                 }
 298
 299                 internal void FromXml2 (SecurityElement e)
 300                 {
 301                         SecurityElement nps = e.SearchForChildByTag ("NamedPermissionSets");
 302                         if ((nps != null) && (nps.Children != null) && (nps.Children.Count > 0)) {
 303                                 named_permission_sets.Clear ();
 304                                 foreach (SecurityElement se in nps.Children) {
 305                                         NamedPermissionSet n = new NamedPermissionSet ();
 306                                         n.Resolver = this;
 307                                         n.FromXml (se);
 308                                         named_permission_sets.Add (n);
 309                                 }
 310                         }
 311                 }
 312
 313                 public NamedPermissionSet GetNamedPermissionSet (string name)
 314                 {
 315                         if (name == null)
 316                                 throw new ArgumentNullException ("name");
 317
 318                         foreach (NamedPermissionSet n in named_permission_sets) {
 319                                 if (n.Name == name)
 320                                         return (NamedPermissionSet) n.Copy ();
 321                         }
 322                         return null;
 323                 }
 324
 325                 public void Recover ()
 326                 {
 327                         if (_location == null) {
 328                                 string msg = Locale.GetText ("Only file based policies may be recovered.");
 329                                 throw new PolicyException (msg);
 330                         }
 331
 332                         string backup = _location + ".backup";
 333                         if (!File.Exists (backup)) {
 334                                 string msg = Locale.GetText ("No policy backup exists.");
 335                                 throw new PolicyException (msg);
 336                         }
 337
 338                         try {
 339                                 File.Copy (backup, _location, true);
 340                         }
 341                         catch (Exception e) {
 342                                 string msg = Locale.GetText ("Couldn't replace the policy file with it's backup.");
 343                                 throw new PolicyException (msg, e);
 344                         }
 345                 }
 346
 347                 public void RemoveFullTrustAssembly (StrongName sn)
 348                 {
 349                         if (sn == null)
 350                                 throw new ArgumentNullException ("sn");
 351
 352                         StrongNameMembershipCondition s = new StrongNameMembershipCondition (sn.PublicKey, sn.Name, sn.Version);
 353                         RemoveFullTrustAssembly (s);
 354                 }
 355
 356                 public void RemoveFullTrustAssembly (StrongNameMembershipCondition snMC)
 357                 {
 358                         if (snMC == null)
 359                                 throw new ArgumentNullException ("snMC");
 360
 361                         if (((IList) full_trust_assemblies).Contains (snMC))
 362                                 ((IList) full_trust_assemblies).Remove (snMC);
 363
 364                         else
 365                                 throw new ArgumentException (
 366                                         Locale.GetText ("sn does not have full trust."));
 367                 }
 368
 369                 public NamedPermissionSet RemoveNamedPermissionSet (NamedPermissionSet permSet)
 370                 {
 371                         if (permSet == null)
 372                                 throw new ArgumentNullException ("permSet");
 373
 374                         return RemoveNamedPermissionSet (permSet.Name);
 375                 }
 376
 377                 public NamedPermissionSet RemoveNamedPermissionSet (string name)
 378                 {
 379                         if (name == null)
 380                                 throw new ArgumentNullException ("name");
 381                         if (DefaultPolicies.ReservedNames.IsReserved (name))
 382                                 throw new ArgumentException (Locale.GetText ("Reserved name"));
 383
 384                         foreach (NamedPermissionSet nps in named_permission_sets) {
 385                                 if (name == nps.Name) {
 386                                         named_permission_sets.Remove (nps);
 387                                         return nps;
 388                                 }
 389                         }
 390                         string msg = String.Format (Locale.GetText ("Name '{0}' cannot be found."), name);
 391                         throw new ArgumentException (msg, "name");
 392                 }
 393
 394                 public void Reset ()
 395                 {
 396                         if (fullNames != null)
 397                                 fullNames.Clear ();
 398                         full_trust_assemblies.Clear ();
 399                         named_permission_sets.Clear ();
 400
 401                         if (_type != PolicyLevelType.AppDomain) {
 402                                 // because the policy doesn't exist LoadFromFile will try to
 403                                 // 1. use the .default file if existing (like Fx 2.0 does); or
 404                                 // 2. use the hard-coded default values
 405                                 // and recreate a policy file
 406                                 if ((_location != null) && (File.Exists (_location))) {
 407                                         try {
 408                                                 File.Delete (_location);
 409                                         }
 410                                         catch {}
 411                                 }
 412                                 LoadFromFile (_location);
 413                         }
 414                         else {
 415                                 named_permission_sets.Add (DefaultPolicies.LocalIntranet);
 416                                 named_permission_sets.Add (DefaultPolicies.Internet);
 417                                 named_permission_sets.Add (DefaultPolicies.SkipVerification);
 418                                 named_permission_sets.Add (DefaultPolicies.Execution);
 419                                 named_permission_sets.Add (DefaultPolicies.Nothing);
 420                                 named_permission_sets.Add (DefaultPolicies.Everything);
 421                                 named_permission_sets.Add (DefaultPolicies.FullTrust);
 422                         }
 423                 }
 424
 425                 public PolicyStatement Resolve (Evidence evidence)
 426                 {
 427                         if (evidence == null)
 428                                 throw new ArgumentNullException ("evidence");
 429
 430                         PolicyStatement ps = root_code_group.Resolve (evidence);
 431                         return ((ps != null) ? ps : PolicyStatement.Empty ());
 432                 }
 433
 434                 public CodeGroup ResolveMatchingCodeGroups (Evidence evidence)
 435                 {
 436                         if (evidence == null)
 437                                 throw new ArgumentNullException ("evidence");
 438
 439                         CodeGroup cg = root_code_group.ResolveMatchingCodeGroups (evidence);
 440                         // TODO
 441                         return ((cg != null) ? cg : null);
 442
 443                 }
 444
 445                 public SecurityElement ToXml ()
 446                 {
 447                         Hashtable fullNames = new Hashtable ();
 448                         // only StrongNameMembershipCondition so no need to loop
 449                         if (full_trust_assemblies.Count > 0) {
 450                                 if (!fullNames.Contains ("StrongNameMembershipCondition")) {
 451                                         fullNames.Add ("StrongNameMembershipCondition", typeof (StrongNameMembershipCondition).FullName);
 452                                 }
 453                         }
 454
 455                         SecurityElement namedPSs = new SecurityElement ("NamedPermissionSets");
 456                         foreach (NamedPermissionSet nps in named_permission_sets) {
 457                                 SecurityElement se = nps.ToXml ();
 458                                 object objectClass = se.Attributes ["class"];
 459                                 if (!fullNames.Contains (objectClass)) {
 460                                         fullNames.Add (objectClass, nps.GetType ().FullName);
 461                                 }
 462                                 namedPSs.AddChild (se);
 463                         }
 464
 465                         SecurityElement fta = new SecurityElement ("FullTrustAssemblies");
 466                         foreach (StrongNameMembershipCondition snmc in full_trust_assemblies) {
 467                                 fta.AddChild (snmc.ToXml (this));
 468                         }
 469
 470                         SecurityElement security_classes = new SecurityElement ("SecurityClasses");
 471                         if (fullNames.Count > 0) {
 472                                 foreach (DictionaryEntry de in fullNames) {
 473                                         SecurityElement sc = new SecurityElement ("SecurityClass");
 474                                         sc.AddAttribute ("Name", (string)de.Key);
 475                                         sc.AddAttribute ("Description", (string)de.Value);
 476                                         security_classes.AddChild (sc);
 477                                 }
 478                         }
 479
 480                         SecurityElement element = new SecurityElement (typeof (System.Security.Policy.PolicyLevel).Name);
 481                         element.AddAttribute ("version", "1");
 482                         element.AddChild (security_classes);
 483                         element.AddChild (namedPSs);
 484                         if (root_code_group != null) {
 485                                 element.AddChild (root_code_group.ToXml (this));
 486                         }
 487                         element.AddChild (fta);
 488
 489                         return element;
 490                 }
 491
 492                 // internal stuff
 493
 494                 // NOTE: Callers are expected to check for ControlPolicy
 495                 internal void Save ()
 496                 {
 497                         if (_type == PolicyLevelType.AppDomain) {
 498                                 throw new PolicyException (Locale.GetText (
 499                                         "Can't save AppDomain PolicyLevel"));
 500                         }
 501
 502                         if (_location != null) {
 503                                 try {
 504                                         if (File.Exists (_location)) {
 505                                                 File.Copy (_location, _location + ".backup", true);
 506                                         }
 507                                 }
 508                                 catch (Exception) {
 509                                 }
 510                                 finally {
 511                                         using (StreamWriter sw = new StreamWriter (_location)) {
 512                                                 sw.Write (ToXml ().ToString ());
 513                                                 sw.Close ();
 514                                         }
 515                                 }
 516                         }
 517                 }
 518
 519                 // Hardcode defaults in case
 520                 // (a) the specified policy file doesn't exists; and
 521                 // (b) no corresponding default policy file exists
 522                 internal void CreateDefaultLevel (PolicyLevelType type)
 523                 {
 524                         PolicyStatement psu = new PolicyStatement (new PermissionSet (PermissionState.Unrestricted));
 525
 526                         switch (type) {
 527                         case PolicyLevelType.Machine:
 528                                 // by default all stuff is in the machine policy...
 529                                 root_code_group = new UnionCodeGroup (new ZoneMembershipCondition (SecurityZone.MyComputer), psu);
 530                                 root_code_group.Name = "All_Code";
 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                         // (default) assemblies that are fully trusted during policy resolution
 542                         full_trust_assemblies.Clear ();
 543                         full_trust_assemblies.Add (DefaultPolicies.FullTrustMembership ("mscorlib", DefaultPolicies.Key.Ecma));
 544                         full_trust_assemblies.Add (DefaultPolicies.FullTrustMembership ("System", DefaultPolicies.Key.Ecma));
 545                         full_trust_assemblies.Add (DefaultPolicies.FullTrustMembership ("System.Data", DefaultPolicies.Key.Ecma));
 546                         full_trust_assemblies.Add (DefaultPolicies.FullTrustMembership ("System.DirectoryServices", DefaultPolicies.Key.MsFinal));
 547                         full_trust_assemblies.Add (DefaultPolicies.FullTrustMembership ("System.Drawing", DefaultPolicies.Key.Ecma));
 548                         full_trust_assemblies.Add (DefaultPolicies.FullTrustMembership ("System.Messaging", DefaultPolicies.Key.MsFinal));
 549                         full_trust_assemblies.Add (DefaultPolicies.FullTrustMembership ("System.ServiceProcess", DefaultPolicies.Key.MsFinal));
 550                 }
 551
 552                 internal void CreateDefaultNamedPermissionSets ()
 553                 {
 554                         named_permission_sets.Clear ();
 555                         named_permission_sets.Add (DefaultPolicies.LocalIntranet);
 556                         named_permission_sets.Add (DefaultPolicies.Internet);
 557                         named_permission_sets.Add (DefaultPolicies.SkipVerification);
 558                         named_permission_sets.Add (DefaultPolicies.Execution);
 559                         named_permission_sets.Add (DefaultPolicies.Nothing);
 560                         named_permission_sets.Add (DefaultPolicies.Everything);
 561                         named_permission_sets.Add (DefaultPolicies.FullTrust);
 562                 }
 563
 564                 internal string ResolveClassName (string className)
 565                 {
 566                         if (fullNames != null) {
 567                                 object name = fullNames [className];
 568                                 if (name != null)
 569                                         return (string) name;
 570                         }
 571                         return className;
 572                 }
 573
 574                 internal bool IsFullTrustAssembly (Assembly a)
 575                 {
 576                         AssemblyName an = a.GetName ();
 577                         StrongNamePublicKeyBlob snpkb = new StrongNamePublicKeyBlob (an.GetPublicKey ());
 578                         StrongNameMembershipCondition snMC = new StrongNameMembershipCondition (snpkb, an.Name, an.Version);
 579                         foreach (StrongNameMembershipCondition sn in full_trust_assemblies) {
 580                                 if (sn.Equals (snMC)) {
 581                                         return true;
 582                                 }
 583                         }
 584                         return false;
 585                 }
 586         }
 587 }