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.Runtime.InteropServices;
  39 using System.Security.Permissions;
  40
  41 using Mono.Xml;
  42
  43 namespace System.Security.Policy {
  44
  45         [Serializable]
  46         public sealed class PolicyLevel {
  47
  48                 string label;
  49                 CodeGroup root_code_group;
  50                 private ArrayList full_trust_assemblies;
  51                 private ArrayList named_permission_sets;
  52                 private string _location;
  53                 private PolicyLevelType _type;
  54                 private Hashtable fullNames;
  55
  56                 internal PolicyLevel (string label, PolicyLevelType type)
  57                 {
  58                         this.label = label;
  59                         _type = type;
  60                         full_trust_assemblies = new ArrayList ();
  61                         named_permission_sets = new ArrayList ();
  62                 }
  63
  64                 internal PolicyLevel (string label, PolicyLevelType type, string filename)
  65                         : this (label, type)
  66                 {
  67                         LoadFromFile (filename);
  68                 }
  69
  70                 internal void LoadFromFile (string filename)
  71                 {
  72                         bool loaded = false;
  73                         try {
  74                                 // check for policy file
  75                                 if (!File.Exists (filename)) {
  76                                         // if it doesn't exist use the default configuration (like Fx 2.0)
  77                                         // ref: http://blogs.msdn.com/shawnfa/archive/2004/04/21/117833.aspx
  78                                         string defcfg = filename + ".default";
  79                                         if (File.Exists (defcfg)) {
  80                                                 // create policy from default file
  81                                                 File.Copy (defcfg, filename);
  82                                         }
  83                                 }
  84                                 // load security policy configuration
  85                                 if (File.Exists (filename)) {
  86                                         using (StreamReader sr = File.OpenText (filename)) {
  87                                                 LoadFromString (sr.ReadToEnd ());
  88                                         }
  89                                         loaded = true;
  90                                 }
  91                                 else {
  92                                         CreateFromHardcodedDefault (_type);
  93                                         loaded = true;
  94                                         Save ();
  95                                 }
  96                         }
  97                         catch {
  98                                 // this can fail in many ways include
  99                                 // * can't lookup policy (path discovery);
 100                                 // * can't copy default file to policy
 101                                 // * can't read policy file;
 102                                 // * can't save hardcoded policy to filename
 103                                 // * can't decode policy file
 104                                 if (!loaded)
 105                                         CreateFromHardcodedDefault (_type);
 106                         }
 107                         finally {
 108                                 _location = filename;
 109                         }
 110                 }
 111
 112                 internal void LoadFromString (string xml)
 113                 {
 114                         SecurityParser parser = new SecurityParser ();
 115                         parser.LoadXml (xml);
 116                         // configuration / mscorlib / security / policy / PolicyLevel
 117                         SecurityElement configuration = parser.ToXml ();
 118                         if (configuration.Tag != "configuration")
 119                                 throw new ArgumentException (Locale.GetText ("missing <configuration> root element"));
 120                         SecurityElement mscorlib = (SecurityElement) configuration.Children [0];
 121                         if (mscorlib.Tag != "mscorlib")
 122                                 throw new ArgumentException (Locale.GetText ("missing <mscorlib> tag"));
 123                         SecurityElement security = (SecurityElement) mscorlib.Children [0];
 124                         if (security.Tag != "security")
 125                                 throw new ArgumentException (Locale.GetText ("missing <security> tag"));
 126                         SecurityElement policy = (SecurityElement) security.Children [0];
 127                         if (policy.Tag != "policy")
 128                                 throw new ArgumentException (Locale.GetText ("missing <policy> tag"));
 129                         SecurityElement policyLevel = (SecurityElement) policy.Children [0];
 130                         FromXml (policyLevel);
 131                 }
 132
 133                 // properties
 134
 135                 public IList FullTrustAssemblies
 136                 {
 137                         get { return full_trust_assemblies; }
 138                 }
 139
 140                 public string Label {
 141                         get { return label; }
 142                 }
 143
 144                 public IList NamedPermissionSets {
 145                         get { return named_permission_sets; }
 146                 }
 147
 148                 public CodeGroup RootCodeGroup {
 149                         get { return root_code_group; }
 150                         set {
 151                                 if (value == null)
 152                                         throw new ArgumentNullException ("value");
 153                                 root_code_group = value;
 154                         }
 155                 }
 156
 157                 public string StoreLocation {
 158                         get { return _location; }
 159                 }
 160
 161 #if NET_2_0
 162                 [ComVisible (false)]
 163                 public PolicyLevelType Type {
 164                         get { return _type; }
 165                 }
 166 #endif
 167
 168                 // methods
 169
 170                 public void AddFullTrustAssembly (StrongName sn)
 171                 {
 172                         if (sn == null)
 173                                 throw new ArgumentNullException ("sn");
 174
 175                         StrongNameMembershipCondition snMC = new StrongNameMembershipCondition(
 176                                 sn.PublicKey, sn.Name, sn.Version);
 177
 178                         AddFullTrustAssembly (snMC);
 179                 }
 180
 181                 public void AddFullTrustAssembly (StrongNameMembershipCondition snMC)
 182                 {
 183                         if (snMC == null)
 184                                 throw new ArgumentNullException ("snMC");
 185
 186                         foreach (StrongNameMembershipCondition sn in full_trust_assemblies) {
 187                                 if (sn.Equals (snMC)) {
 188                                         throw new ArgumentException (Locale.GetText ("sn already has full trust."));
 189                                 }
 190                         }
 191                         full_trust_assemblies.Add (snMC);
 192                 }
 193
 194                 public void AddNamedPermissionSet (NamedPermissionSet permSet)
 195                 {
 196                         if (permSet == null)
 197                                 throw new ArgumentNullException ("permSet");
 198
 199                         foreach (NamedPermissionSet n in named_permission_sets) {
 200                                 if (permSet.Name == n.Name) {
 201                                         throw new ArgumentException (
 202                                                 Locale.GetText ("This NamedPermissionSet is the same an existing NamedPermissionSet."));
 203                                 }
 204                         }
 205                         named_permission_sets.Add (permSet.Copy ());
 206                 }
 207
 208                 public NamedPermissionSet ChangeNamedPermissionSet (string name, PermissionSet pSet)
 209                 {
 210                         if (name == null)
 211                                 throw new ArgumentNullException ("name");
 212                         if (pSet == null)
 213                                 throw new ArgumentNullException ("pSet");
 214                         if (IsReserved (name))
 215                                 throw new ArgumentException (Locale.GetText ("Reserved name"));
 216
 217                         foreach (NamedPermissionSet n in named_permission_sets) {
 218                                 if (name == n.Name) {
 219                                         named_permission_sets.Remove (n);
 220                                         AddNamedPermissionSet (new NamedPermissionSet (name, pSet));
 221                                         return n;
 222                                 }
 223                         }
 224                         throw new ArgumentException (Locale.GetText ("PermissionSet not found"));
 225                 }
 226
 227                 public static PolicyLevel CreateAppDomainLevel ()
 228                 {
 229                         NamedPermissionSet fullTrust = new NamedPermissionSet ("FullTrust", PermissionState.Unrestricted);
 230                         UnionCodeGroup cg = new UnionCodeGroup (new AllMembershipCondition (), new PolicyStatement (fullTrust));
 231                         cg.Name = "All_Code";
 232                         PolicyLevel pl = new PolicyLevel ("AppDomain", PolicyLevelType.AppDomain);
 233                         pl.RootCodeGroup = cg;
 234                         pl.Reset ();
 235                         return pl;
 236                 }
 237
 238                 public void FromXml (SecurityElement e)
 239                 {
 240                         if (e == null)
 241                                 throw new ArgumentNullException ("e");
 242 // MS doesn't throw an exception for this case
 243 //                      if (e.Tag != "PolicyLevel")
 244 //                              throw new ArgumentException (Locale.GetText ("Invalid XML"));
 245
 246                         SecurityElement sc = e.SearchForChildByTag ("SecurityClasses");
 247                         if ((sc != null) && (sc.Children != null) && (sc.Children.Count > 0)) {
 248                                 fullNames = new Hashtable (sc.Children.Count);
 249                                 foreach (SecurityElement se in sc.Children) {
 250                                         fullNames.Add (se.Attributes ["Name"], se.Attributes ["Description"]);
 251                                 }
 252                         }
 253
 254                         SecurityElement nps = e.SearchForChildByTag ("NamedPermissionSets");
 255                         if ((nps != null) && (nps.Children != null) && (nps.Children.Count > 0)) {
 256                                 named_permission_sets.Clear ();
 257                                 foreach (SecurityElement se in nps.Children) {
 258                                         NamedPermissionSet n = new NamedPermissionSet ();
 259                                         n.Resolver = this;
 260                                         n.FromXml (se);
 261                                         named_permission_sets.Add (n);
 262                                 }
 263                         }
 264
 265                         SecurityElement cg = e.SearchForChildByTag ("CodeGroup");
 266                         if ((cg != null) && (cg.Children != null) && (cg.Children.Count > 0)) {
 267                                 root_code_group = CodeGroup.CreateFromXml (cg, this);
 268                         }
 269                         else
 270                                 throw new ArgumentException (Locale.GetText ("Missing Root CodeGroup"));
 271
 272                         SecurityElement fta = e.SearchForChildByTag ("FullTrustAssemblies");
 273                         if ((fta != null) && (fta.Children != null) && (fta.Children.Count > 0)) {
 274                                 full_trust_assemblies.Clear ();
 275                                 foreach (SecurityElement se in fta.Children) {
 276                                         if (se.Tag != "IMembershipCondition")
 277                                                 throw new ArgumentException (Locale.GetText ("Invalid XML"));
 278                                         string className = se.Attribute ("class");
 279                                         if (className.IndexOf ("StrongNameMembershipCondition") < 0)
 280                                                 throw new ArgumentException (Locale.GetText ("Invalid XML - must be StrongNameMembershipCondition"));
 281                                         // we directly use StrongNameMembershipCondition
 282                                         full_trust_assemblies.Add (new StrongNameMembershipCondition (se));
 283                                 }
 284                         }
 285                 }
 286
 287                 public NamedPermissionSet GetNamedPermissionSet (string name)
 288                 {
 289                         if (name == null)
 290                                 throw new ArgumentNullException ("name");
 291
 292                         foreach (NamedPermissionSet n in named_permission_sets) {
 293                                 if (n.Name == name)
 294                                         return (NamedPermissionSet) n.Copy ();
 295                         }
 296                         return null;
 297                 }
 298
 299                 [MonoTODO]
 300                 public void Recover ()
 301                 {
 302                         throw new NotImplementedException ();
 303                 }
 304
 305                 public void RemoveFullTrustAssembly (StrongName sn)
 306                 {
 307                         if (sn == null)
 308                                 throw new ArgumentNullException ("sn");
 309
 310                         StrongNameMembershipCondition s = new StrongNameMembershipCondition (sn.PublicKey, sn.Name, sn.Version);
 311                         RemoveFullTrustAssembly (s);
 312                 }
 313
 314                 public void RemoveFullTrustAssembly (StrongNameMembershipCondition snMC)
 315                 {
 316                         if (snMC == null)
 317                                 throw new ArgumentNullException ("snMC");
 318
 319                         if (((IList) full_trust_assemblies).Contains (snMC))
 320                                 ((IList) full_trust_assemblies).Remove (snMC);
 321
 322                         else
 323                                 throw new ArgumentException (
 324                                         Locale.GetText ("sn does not have full trust."));
 325                 }
 326
 327                 public NamedPermissionSet RemoveNamedPermissionSet (NamedPermissionSet permSet)
 328                 {
 329                         if (permSet == null)
 330                                 throw new ArgumentNullException ("permSet");
 331
 332                         if (! ((IList )named_permission_sets).Contains (permSet))
 333                                 throw new ArgumentException (
 334                                         Locale.GetText ("permSet cannot be found."));
 335
 336                         ((IList) named_permission_sets).Remove (permSet);
 337
 338                         return permSet;
 339                 }
 340
 341                 [MonoTODO ("Check for reserved names")]
 342                 public NamedPermissionSet RemoveNamedPermissionSet (string name)
 343                 {
 344                         if (name == null)
 345                                 throw new ArgumentNullException ("name");
 346
 347                         foreach (NamedPermissionSet nps in named_permission_sets) {
 348                                 if (name == nps.Name) {
 349                                         named_permission_sets.Remove (nps);
 350                                         return nps;
 351                                 }
 352                         }
 353                         string msg = String.Format (Locale.GetText ("Name '{0}' cannot be found."), name);
 354                         throw new ArgumentException (msg, "name");
 355                 }
 356
 357                 public void Reset ()
 358                 {
 359                         if (fullNames != null)
 360                                 fullNames.Clear ();
 361                         full_trust_assemblies.Clear ();
 362                         named_permission_sets.Clear ();
 363
 364                         if (_type != PolicyLevelType.AppDomain) {
 365                                 // because the policy doesn't exist LoadFromFile will try to
 366                                 // 1. use the .default file if existing (like Fx 2.0 does); or
 367                                 // 2. use the hard-coded default values
 368                                 // and recreate a policy file
 369                                 if ((_location != null) && (File.Exists (_location))) {
 370                                         try {
 371                                                 File.Delete (_location);
 372                                         }
 373                                         catch {}
 374                                 }
 375                                 LoadFromFile (_location);
 376                         }
 377                         else {
 378                                 named_permission_sets.Add (new NamedPermissionSet ("LocalIntranet"));
 379                                 named_permission_sets.Add (new NamedPermissionSet ("Internet"));
 380                                 named_permission_sets.Add (new NamedPermissionSet ("SkipVerification"));
 381                                 named_permission_sets.Add (new NamedPermissionSet ("Execution"));
 382                                 named_permission_sets.Add (new NamedPermissionSet ("Nothing"));
 383                                 named_permission_sets.Add (new NamedPermissionSet ("Everything"));
 384                                 named_permission_sets.Add (new NamedPermissionSet ("FullTrust"));
 385                         }
 386                 }
 387
 388                 public PolicyStatement Resolve (Evidence evidence)
 389                 {
 390                         if (evidence == null)
 391                                 throw new ArgumentNullException ("evidence");
 392
 393                         PolicyStatement ps = root_code_group.Resolve (evidence);
 394                         return ((ps != null) ? ps : PolicyStatement.Empty ());
 395                 }
 396
 397                 public CodeGroup ResolveMatchingCodeGroups (Evidence evidence)
 398                 {
 399                         if (evidence == null)
 400                                 throw new ArgumentNullException ("evidence");
 401
 402                         CodeGroup cg = root_code_group.ResolveMatchingCodeGroups (evidence);
 403                         // TODO
 404                         return ((cg != null) ? cg : null);
 405
 406                 }
 407
 408                 public SecurityElement ToXml ()
 409                 {
 410                         Hashtable fullNames = new Hashtable ();
 411                         // only StrongNameMembershipCondition so no need to loop
 412                         if (full_trust_assemblies.Count > 0) {
 413                                 if (!fullNames.Contains ("StrongNameMembershipCondition")) {
 414                                         fullNames.Add ("StrongNameMembershipCondition", typeof (StrongNameMembershipCondition).FullName);
 415                                 }
 416                         }
 417
 418                         SecurityElement namedPSs = new SecurityElement ("NamedPermissionSets");
 419                         foreach (NamedPermissionSet nps in named_permission_sets) {
 420                                 SecurityElement se = nps.ToXml ();
 421                                 object objectClass = se.Attributes ["class"];
 422                                 if (!fullNames.Contains (objectClass)) {
 423                                         fullNames.Add (objectClass, nps.GetType ().FullName);
 424                                 }
 425                                 namedPSs.AddChild (se);
 426                         }
 427
 428                         SecurityElement fta = new SecurityElement ("FullTrustAssemblies");
 429                         foreach (StrongNameMembershipCondition snmc in full_trust_assemblies) {
 430                                 fta.AddChild (snmc.ToXml (this));
 431                         }
 432
 433                         SecurityElement security_classes = new SecurityElement ("SecurityClasses");
 434                         if (fullNames.Count > 0) {
 435                                 foreach (DictionaryEntry de in fullNames) {
 436                                         SecurityElement sc = new SecurityElement ("SecurityClass");
 437                                         sc.AddAttribute ("Name", (string)de.Key);
 438                                         sc.AddAttribute ("Description", (string)de.Value);
 439                                         security_classes.AddChild (sc);
 440                                 }
 441                         }
 442
 443                         SecurityElement element = new SecurityElement (typeof (System.Security.Policy.PolicyLevel).Name);
 444                         element.AddAttribute ("version", "1");
 445                         element.AddChild (security_classes);
 446                         element.AddChild (namedPSs);
 447                         if (root_code_group != null) {
 448                                 element.AddChild (root_code_group.ToXml (this));
 449                         }
 450                         element.AddChild (fta);
 451
 452                         return element;
 453                 }
 454
 455                 // internal stuff
 456
 457                 internal bool IsReserved (string name)
 458                 {
 459                         switch (name) {
 460                                 case "FullTrust":
 461                                 case "LocalIntranet":
 462                                 case "Internet":
 463                                 case "SkipVerification":
 464                                 case "Execution":
 465                                 case "Nothing":
 466                                 case "Everything":
 467                                         // FIXME: Are there others ?
 468                                         return true;
 469                                 default:
 470                                         return false;
 471                         }
 472                 }
 473
 474                 // NOTE: Callers are expected to check for ControlPolicy
 475                 internal void Save ()
 476                 {
 477                         if (_type == PolicyLevelType.AppDomain) {
 478                                 throw new PolicyException (Locale.GetText (
 479                                         "Can't save AppDomain PolicyLevel"));
 480                         }
 481
 482                         if (_location != null) {
 483                                 using (StreamWriter sw = new StreamWriter (_location)) {
 484                                         sw.Write (ToXml ().ToString ());
 485                                         sw.Close ();
 486                                 }
 487                         }
 488                 }
 489
 490                 // TODO : hardcode defaults in case
 491                 // (a) the specified policy file doesn't exists; and
 492                 // (b) no corresponding default policy file exists
 493                 internal void CreateFromHardcodedDefault (PolicyLevelType type)
 494                 {
 495                         PolicyStatement psu = new PolicyStatement (new PermissionSet (PermissionState.Unrestricted));
 496
 497                         switch (type) {
 498                         case PolicyLevelType.Machine:
 499                                 // by default all stuff is in the machine policy...
 500                                 root_code_group = new UnionCodeGroup (new ZoneMembershipCondition (SecurityZone.MyComputer), psu);
 501                                 root_code_group.Name = "All_Code";
 502                                 break;
 503                         case PolicyLevelType.User:
 504                         case PolicyLevelType.Enterprise:
 505                         case PolicyLevelType.AppDomain:
 506                                 // while the other policies don't restrict anything
 507                                 root_code_group = new UnionCodeGroup (new AllMembershipCondition (), psu);
 508                                 root_code_group.Name = "All_Code";
 509                                 break;
 510                         }
 511                 }
 512
 513                 internal string ResolveClassName (string className)
 514                 {
 515                         if (fullNames != null) {
 516                                 object name = fullNames [className];
 517                                 if (name != null)
 518                                         return (string) name;
 519                         }
 520                         return className;
 521                 }
 522         }
 523 }