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 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.Security.Permissions;
  39
  40 using Mono.Xml;
  41
  42 namespace System.Security.Policy {
  43
  44         [Serializable]
  45         public sealed class PolicyLevel {
  46
  47                 string label;
  48                 CodeGroup root_code_group;
  49                 private ArrayList full_trust_assemblies;
  50                 private ArrayList named_permission_sets;
  51                 private string _location;
  52                 private PolicyLevelType _type;
  53                 private Hashtable fullNames;
  54
  55                 internal PolicyLevel (string label, PolicyLevelType type)
  56                 {
  57                         this.label = label;
  58                         _type = type;
  59                         full_trust_assemblies = new ArrayList ();
  60                         named_permission_sets = new ArrayList ();
  61                 }
  62
  63                 internal PolicyLevel (string label, PolicyLevelType type, string filename)
  64                         : this (label, type)
  65                 {
  66                         LoadFromFile (filename);
  67                 }
  68
  69                 internal void LoadFromFile (string filename)
  70                 {
  71                         bool loaded = false;
  72                         try {
  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                                                 LoadFromString (sr.ReadToEnd ());
  87                                         }
  88                                         loaded = true;
  89                                 }
  90                                 else {
  91                                         CreateFromHardcodedDefault (_type);
  92                                         loaded = true;
  93                                         Save ();
  94                                 }
  95                         }
  96                         catch {
  97                                 // this can fail in many ways include
  98                                 // * can't lookup policy (path discovery);
  99                                 // * can't copy default file to policy
 100                                 // * can't read policy file;
 101                                 // * can't save hardcoded policy to filename
 102                                 // * can't decode policy file
 103                                 if (!loaded)
 104                                         CreateFromHardcodedDefault (_type);
 105                         }
 106                         finally {
 107                                 _location = filename;
 108                         }
 109                 }
 110
 111                 internal void LoadFromString (string xml)
 112                 {
 113                         SecurityParser parser = new SecurityParser ();
 114                         parser.LoadXml (xml);
 115                         // configuration / mscorlib / security / policy / PolicyLevel
 116                         SecurityElement configuration = parser.ToXml ();
 117                         if (configuration.Tag != "configuration")
 118                                 throw new ArgumentException (Locale.GetText ("missing <configuration> root element"));
 119                         SecurityElement mscorlib = (SecurityElement) configuration.Children [0];
 120                         if (mscorlib.Tag != "mscorlib")
 121                                 throw new ArgumentException (Locale.GetText ("missing <mscorlib> tag"));
 122                         SecurityElement security = (SecurityElement) mscorlib.Children [0];
 123                         if (security.Tag != "security")
 124                                 throw new ArgumentException (Locale.GetText ("missing <security> tag"));
 125                         SecurityElement policy = (SecurityElement) security.Children [0];
 126                         if (policy.Tag != "policy")
 127                                 throw new ArgumentException (Locale.GetText ("missing <policy> tag"));
 128                         SecurityElement policyLevel = (SecurityElement) policy.Children [0];
 129                         FromXml (policyLevel);
 130                 }
 131
 132                 // properties
 133
 134                 public IList FullTrustAssemblies
 135                 {
 136                         get { return full_trust_assemblies; }
 137                 }
 138
 139                 public string Label {
 140                         get { return label; }
 141                 }
 142
 143                 public IList NamedPermissionSets {
 144                         get { return named_permission_sets; }
 145                 }
 146
 147                 public CodeGroup RootCodeGroup {
 148                         get { return root_code_group; }
 149                         set {
 150                                 if (value == null)
 151                                         throw new ArgumentNullException ("value");
 152                                 root_code_group = value;
 153                         }
 154                 }
 155
 156                 public string StoreLocation {
 157                         get { return _location; }
 158                 }
 159
 160 #if NET_2_0
 161                 public PolicyLevelType Type {
 162                         get { return _type; }
 163                 }
 164 #endif
 165
 166                 // methods
 167
 168                 public void AddFullTrustAssembly (StrongName sn)
 169                 {
 170                         if (sn == null)
 171                                 throw new ArgumentNullException ("sn");
 172
 173                         StrongNameMembershipCondition snMC = new StrongNameMembershipCondition(
 174                                 sn.PublicKey, sn.Name, sn.Version);
 175
 176                         AddFullTrustAssembly (snMC);
 177                 }
 178
 179                 public void AddFullTrustAssembly (StrongNameMembershipCondition snMC)
 180                 {
 181                         if (snMC == null)
 182                                 throw new ArgumentNullException ("snMC");
 183
 184                         foreach (StrongNameMembershipCondition sn in full_trust_assemblies) {
 185                                 if (sn.Equals (snMC)) {
 186                                         throw new ArgumentException (Locale.GetText ("sn already has full trust."));
 187                                 }
 188                         }
 189                         full_trust_assemblies.Add (snMC);
 190                 }
 191
 192                 public void AddNamedPermissionSet (NamedPermissionSet permSet)
 193                 {
 194                         if (permSet == null)
 195                                 throw new ArgumentNullException ("permSet");
 196
 197                         foreach (NamedPermissionSet n in named_permission_sets) {
 198                                 if (permSet.Name == n.Name) {
 199                                         throw new ArgumentException (
 200                                                 Locale.GetText ("This NamedPermissionSet is the same an existing NamedPermissionSet."));
 201                                 }
 202                         }
 203                         named_permission_sets.Add (permSet.Copy ());
 204                 }
 205
 206                 public NamedPermissionSet ChangeNamedPermissionSet (string name, PermissionSet pSet)
 207                 {
 208                         if (name == null)
 209                                 throw new ArgumentNullException ("name");
 210                         if (pSet == null)
 211                                 throw new ArgumentNullException ("pSet");
 212                         if (IsReserved (name))
 213                                 throw new ArgumentException (Locale.GetText ("Reserved name"));
 214
 215                         foreach (NamedPermissionSet n in named_permission_sets) {
 216                                 if (name == n.Name) {
 217                                         named_permission_sets.Remove (n);
 218                                         AddNamedPermissionSet (new NamedPermissionSet (name, pSet));
 219                                         return n;
 220                                 }
 221                         }
 222                         throw new ArgumentException (Locale.GetText ("PermissionSet not found"));
 223                 }
 224
 225                 public static PolicyLevel CreateAppDomainLevel ()
 226                 {
 227                         NamedPermissionSet fullTrust = new NamedPermissionSet ("FullTrust", PermissionState.Unrestricted);
 228                         UnionCodeGroup cg = new UnionCodeGroup (new AllMembershipCondition (), new PolicyStatement (fullTrust));
 229                         cg.Name = "All_Code";
 230                         PolicyLevel pl = new PolicyLevel ("AppDomain", PolicyLevelType.AppDomain);
 231                         pl.RootCodeGroup = cg;
 232                         pl.Reset ();
 233                         return pl;
 234                 }
 235
 236                 public void FromXml (SecurityElement e)
 237                 {
 238                         if (e == null)
 239                                 throw new ArgumentNullException ("e");
 240 // MS doesn't throw an exception for this case
 241 //                      if (e.Tag != "PolicyLevel")
 242 //                              throw new ArgumentException (Locale.GetText ("Invalid XML"));
 243
 244                         SecurityElement sc = e.SearchForChildByTag ("SecurityClasses");
 245                         if ((sc != null) && (sc.Children != null) && (sc.Children.Count > 0)) {
 246                                 fullNames = new Hashtable (sc.Children.Count);
 247                                 foreach (SecurityElement se in sc.Children) {
 248                                         fullNames.Add (se.Attributes ["Name"], se.Attributes ["Description"]);
 249                                 }
 250                         }
 251
 252                         SecurityElement nps = e.SearchForChildByTag ("NamedPermissionSets");
 253                         if ((nps != null) && (nps.Children != null) && (nps.Children.Count > 0)) {
 254                                 named_permission_sets.Clear ();
 255                                 foreach (SecurityElement se in nps.Children) {
 256                                         NamedPermissionSet n = new NamedPermissionSet ();
 257                                         n.Resolver = this;
 258                                         n.FromXml (se);
 259                                         named_permission_sets.Add (n);
 260                                 }
 261                         }
 262
 263                         SecurityElement cg = e.SearchForChildByTag ("CodeGroup");
 264                         if ((cg != null) && (cg.Children != null) && (cg.Children.Count > 0)) {
 265                                 root_code_group = CodeGroup.CreateFromXml (cg, this);
 266                         }
 267                         else
 268                                 throw new ArgumentException (Locale.GetText ("Missing Root CodeGroup"));
 269
 270                         SecurityElement fta = e.SearchForChildByTag ("FullTrustAssemblies");
 271                         if ((fta != null) && (fta.Children != null) && (fta.Children.Count > 0)) {
 272                                 full_trust_assemblies.Clear ();
 273                                 foreach (SecurityElement se in fta.Children) {
 274                                         if (se.Tag != "IMembershipCondition")
 275                                                 throw new ArgumentException (Locale.GetText ("Invalid XML"));
 276                                         string className = se.Attribute ("class");
 277                                         if (className.IndexOf ("StrongNameMembershipCondition") < 0)
 278                                                 throw new ArgumentException (Locale.GetText ("Invalid XML - must be StrongNameMembershipCondition"));
 279                                         // we directly use StrongNameMembershipCondition
 280                                         full_trust_assemblies.Add (new StrongNameMembershipCondition (se));
 281                                 }
 282                         }
 283                 }
 284
 285                 public NamedPermissionSet GetNamedPermissionSet (string name)
 286                 {
 287                         if (name == null)
 288                                 throw new ArgumentNullException ("name");
 289
 290                         foreach (NamedPermissionSet n in named_permission_sets) {
 291                                 if (n.Name == name)
 292                                         return (NamedPermissionSet) n.Copy ();
 293                         }
 294                         return null;
 295                 }
 296
 297                 [MonoTODO]
 298                 public void Recover ()
 299                 {
 300                         throw new NotImplementedException ();
 301                 }
 302
 303                 public void RemoveFullTrustAssembly (StrongName sn)
 304                 {
 305                         if (sn == null)
 306                                 throw new ArgumentNullException ("sn");
 307
 308                         StrongNameMembershipCondition s = new StrongNameMembershipCondition (sn.PublicKey, sn.Name, sn.Version);
 309                         RemoveFullTrustAssembly (s);
 310                 }
 311
 312                 public void RemoveFullTrustAssembly (StrongNameMembershipCondition snMC)
 313                 {
 314                         if (snMC == null)
 315                                 throw new ArgumentNullException ("snMC");
 316
 317                         if (((IList) full_trust_assemblies).Contains (snMC))
 318                                 ((IList) full_trust_assemblies).Remove (snMC);
 319
 320                         else
 321                                 throw new ArgumentException (
 322                                         Locale.GetText ("sn does not have full trust."));
 323                 }
 324
 325                 public NamedPermissionSet RemoveNamedPermissionSet (NamedPermissionSet permSet)
 326                 {
 327                         if (permSet == null)
 328                                 throw new ArgumentNullException ("permSet");
 329
 330                         if (! ((IList )named_permission_sets).Contains (permSet))
 331                                 throw new ArgumentException (
 332                                         Locale.GetText ("permSet cannot be found."));
 333
 334                         ((IList) named_permission_sets).Remove (permSet);
 335
 336                         return permSet;
 337                 }
 338
 339                 [MonoTODO ("Check for reserved names")]
 340                 public NamedPermissionSet RemoveNamedPermissionSet (string name)
 341                 {
 342                         if (name == null)
 343                                 throw new ArgumentNullException ("name");
 344
 345                         foreach (NamedPermissionSet nps in named_permission_sets) {
 346                                 if (name == nps.Name) {
 347                                         named_permission_sets.Remove (nps);
 348                                         return nps;
 349                                 }
 350                         }
 351                         string msg = String.Format (Locale.GetText ("Name '{0}' cannot be found."), name);
 352                         throw new ArgumentException (msg, "name");
 353                 }
 354
 355                 public void Reset ()
 356                 {
 357                         if (fullNames != null)
 358                                 fullNames.Clear ();
 359                         full_trust_assemblies.Clear ();
 360                         named_permission_sets.Clear ();
 361
 362                         if (_type != PolicyLevelType.AppDomain) {
 363                                 // because the policy doesn't exist LoadFromFile will try to
 364                                 // 1. use the .default file if existing (like Fx 2.0 does); or
 365                                 // 2. use the hard-coded default values
 366                                 // and recreate a policy file
 367                                 if ((_location != null) && (File.Exists (_location))) {
 368                                         try {
 369                                                 File.Delete (_location);
 370                                         }
 371                                         catch {}
 372                                 }
 373                                 LoadFromFile (_location);
 374                         }
 375                         else {
 376                                 named_permission_sets.Add (new NamedPermissionSet ("LocalIntranet"));
 377                                 named_permission_sets.Add (new NamedPermissionSet ("Internet"));
 378                                 named_permission_sets.Add (new NamedPermissionSet ("SkipVerification"));
 379                                 named_permission_sets.Add (new NamedPermissionSet ("Execution"));
 380                                 named_permission_sets.Add (new NamedPermissionSet ("Nothing"));
 381                                 named_permission_sets.Add (new NamedPermissionSet ("Everything"));
 382                                 named_permission_sets.Add (new NamedPermissionSet ("FullTrust"));
 383                         }
 384                 }
 385
 386                 public PolicyStatement Resolve (Evidence evidence)
 387                 {
 388                         if (evidence == null)
 389                                 throw new ArgumentNullException ("evidence");
 390
 391                         PolicyStatement ps = root_code_group.Resolve (evidence);
 392                         return ((ps != null) ? ps : PolicyStatement.Empty ());
 393                 }
 394
 395                 public CodeGroup ResolveMatchingCodeGroups (Evidence evidence)
 396                 {
 397                         if (evidence == null)
 398                                 throw new ArgumentNullException ("evidence");
 399
 400                         CodeGroup cg = root_code_group.ResolveMatchingCodeGroups (evidence);
 401                         // TODO
 402                         return ((cg != null) ? cg : null);
 403
 404                 }
 405
 406                 public SecurityElement ToXml ()
 407                 {
 408                         Hashtable fullNames = new Hashtable ();
 409                         // only StrongNameMembershipCondition so no need to loop
 410                         if (full_trust_assemblies.Count > 0) {
 411                                 if (!fullNames.Contains ("StrongNameMembershipCondition")) {
 412                                         fullNames.Add ("StrongNameMembershipCondition", typeof (StrongNameMembershipCondition).FullName);
 413                                 }
 414                         }
 415
 416                         SecurityElement namedPSs = new SecurityElement ("NamedPermissionSets");
 417                         foreach (NamedPermissionSet nps in named_permission_sets) {
 418                                 SecurityElement se = nps.ToXml ();
 419                                 object objectClass = se.Attributes ["class"];
 420                                 if (!fullNames.Contains (objectClass)) {
 421                                         fullNames.Add (objectClass, nps.GetType ().FullName);
 422                                 }
 423                                 namedPSs.AddChild (se);
 424                         }
 425
 426                         SecurityElement fta = new SecurityElement ("FullTrustAssemblies");
 427                         foreach (StrongNameMembershipCondition snmc in full_trust_assemblies) {
 428                                 fta.AddChild (snmc.ToXml (this));
 429                         }
 430
 431                         SecurityElement security_classes = new SecurityElement ("SecurityClasses");
 432                         if (fullNames.Count > 0) {
 433                                 foreach (DictionaryEntry de in fullNames) {
 434                                         SecurityElement sc = new SecurityElement ("SecurityClass");
 435                                         sc.AddAttribute ("Name", (string)de.Key);
 436                                         sc.AddAttribute ("Description", (string)de.Value);
 437                                         security_classes.AddChild (sc);
 438                                 }
 439                         }
 440
 441                         SecurityElement element = new SecurityElement (typeof (System.Security.Policy.PolicyLevel).Name);
 442                         element.AddAttribute ("version", "1");
 443                         element.AddChild (security_classes);
 444                         element.AddChild (namedPSs);
 445                         if (root_code_group != null) {
 446                                 element.AddChild (root_code_group.ToXml (this));
 447                         }
 448                         element.AddChild (fta);
 449
 450                         return element;
 451                 }
 452
 453                 // internal stuff
 454
 455                 internal bool IsReserved (string name)
 456                 {
 457                         switch (name) {
 458                                 case "FullTrust":
 459                                 case "LocalIntranet":
 460                                 case "Internet":
 461                                 case "SkipVerification":
 462                                 case "Execution":
 463                                 case "Nothing":
 464                                 case "Everything":
 465                                         // FIXME: Are there others ?
 466                                         return true;
 467                                 default:
 468                                         return false;
 469                         }
 470                 }
 471
 472                 // NOTE: Callers are expected to check for ControlPolicy
 473                 internal void Save ()
 474                 {
 475                         if (_type == PolicyLevelType.AppDomain) {
 476                                 throw new PolicyException (Locale.GetText (
 477                                         "Can't save AppDomain PolicyLevel"));
 478                         }
 479
 480                         if (_location != null) {
 481                                 using (StreamWriter sw = new StreamWriter (_location)) {
 482                                         sw.Write (ToXml ().ToString ());
 483                                         sw.Close ();
 484                                 }
 485                         }
 486                 }
 487
 488                 // TODO : hardcode defaults in case
 489                 // (a) the specified policy file doesn't exists; and
 490                 // (b) no corresponding default policy file exists
 491                 internal void CreateFromHardcodedDefault (PolicyLevelType type)
 492                 {
 493                         PolicyStatement psu = new PolicyStatement (new PermissionSet (PermissionState.Unrestricted));
 494
 495                         switch (type) {
 496                         case PolicyLevelType.Machine:
 497                                 // by default all stuff is in the machine policy...
 498                                 root_code_group = new UnionCodeGroup (new ZoneMembershipCondition (SecurityZone.MyComputer), psu);
 499                                 root_code_group.Name = "All_Code";
 500                                 break;
 501                         case PolicyLevelType.User:
 502                         case PolicyLevelType.Enterprise:
 503                         case PolicyLevelType.AppDomain:
 504                                 // while the other policies don't restrict anything
 505                                 root_code_group = new UnionCodeGroup (new AllMembershipCondition (), psu);
 506                                 root_code_group.Name = "All_Code";
 507                                 break;
 508                         }
 509                 }
 510
 511                 internal string ResolveClassName (string className)
 512                 {
 513                         if (fullNames != null) {
 514                                 object name = fullNames [className];
 515                                 if (name != null)
 516                                         return (string) name;
 517                         }
 518                         return className;
 519                 }
 520         }
 521 }