mcs/class/System.Web/System.Web.Handlers/AssemblyResourceLoader.cs

   1 //
   2 // System.Web.Handlers.AssemblyResourceLoader
   3 //
   4 // Authors:
   5 //      Ben Maurer (bmaurer@users.sourceforge.net)
   6 //      Marek Habersack <grendel@twistedcode.net>
   7 //
   8 // (C) 2003 Ben Maurer
   9 // (C) 2010 Novell, Inc (http://novell.com/)
  10
  11 //
  12 // Permission is hereby granted, free of charge, to any person obtaining
  13 // a copy of this software and associated documentation files (the
  14 // "Software"), to deal in the Software without restriction, including
  15 // without limitation the rights to use, copy, modify, merge, publish,
  16 // distribute, sublicense, and/or sell copies of the Software, and to
  17 // permit persons to whom the Software is furnished to do so, subject to
  18 // the following conditions:
  19 //
  20 // The above copyright notice and this permission notice shall be
  21 // included in all copies or substantial portions of the Software.
  22 //
  23 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  24 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  25 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  26 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  27 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  28 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  29 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  30 //
  31
  32 using System.Web.UI;
  33 using System.Globalization;
  34 using System.Reflection;
  35 using System.IO;
  36 using System.Resources;
  37 using System.Collections;
  38 using System.Collections.Generic;
  39 using System.Security.Cryptography;
  40 using System.Text;
  41 using System.Text.RegularExpressions;
  42 using System.Threading;
  43 using System.Web.Configuration;
  44 using System.Web.Util;
  45
  46 namespace System.Web.Handlers
  47 {
  48 #if SYSTEM_WEB_EXTENSIONS
  49         partial class ScriptResourceHandler
  50         {
  51                 const string HandlerFileName = "ScriptResource.axd";
  52                 static Assembly currAsm = typeof (ScriptResourceHandler).Assembly;
  53 #else
  54         #if NET_2_0
  55         public sealed
  56         #else
  57         internal // since this is in the .config file, we need to support it, since we dont have versoned support.
  58         #endif
  59         class AssemblyResourceLoader : IHttpHandler
  60         {
  61                 const string HandlerFileName = "WebResource.axd";
  62                 static Assembly currAsm = typeof (AssemblyResourceLoader).Assembly;
  63 #endif
  64                 const char QueryParamSeparator = '&';
  65
  66                 static readonly Dictionary <string, AssemblyEmbeddedResources> _embeddedResources = new Dictionary <string, AssemblyEmbeddedResources> (StringComparer.Ordinal);
  67                 static readonly ReaderWriterLockSlim _embeddedResourcesLock = new ReaderWriterLockSlim ();
  68                 static readonly ReaderWriterLockSlim _stringHashCacheLock = new ReaderWriterLockSlim ();
  69                 static readonly Dictionary <string, string> stringHashCache = new Dictionary <string, string> (StringComparer.Ordinal);
  70
  71                 [ThreadStatic]
  72                 static KeyedHashAlgorithm hashAlg;
  73                 static bool canReuseHashAlg = true;
  74
  75                 static KeyedHashAlgorithm ReusableHashAlgorithm {
  76                         get {
  77                                 if (!canReuseHashAlg)
  78                                         return null;
  79
  80                                 if (hashAlg == null) {
  81                                         MachineKeySection mks = MachineKeySection.Config;
  82                                         hashAlg = MachineKeySectionUtils.GetValidationAlgorithm (mks);
  83                                         if (!hashAlg.CanReuseTransform) {
  84                                                 canReuseHashAlg = false;
  85                                                 hashAlg = null;
  86                                         }
  87                                 }
  88
  89                                 if (hashAlg != null)
  90                                         hashAlg.Initialize ();
  91
  92                                 return hashAlg;
  93                         }
  94                 }
  95
  96                 static string GetStringHash (KeyedHashAlgorithm kha, string str)
  97                 {
  98                         if (String.IsNullOrEmpty (str))
  99                                 return String.Empty;
 100
 101                         string result;
 102                         try {
 103                                 _stringHashCacheLock.EnterUpgradeableReadLock ();
 104                                 if (stringHashCache.TryGetValue (str, out result))
 105                                         return result;
 106
 107                                 try {
 108                                         _stringHashCacheLock.EnterWriteLock ();
 109                                         if (stringHashCache.TryGetValue (str, out result))
 110                                                 return result;
 111
 112                                         result = Convert.ToBase64String (kha.ComputeHash (Encoding.UTF8.GetBytes (str)));
 113                                         stringHashCache.Add (str, result);
 114                                 } finally {
 115                                         _stringHashCacheLock.ExitWriteLock ();
 116                                 }
 117                         } finally {
 118                                 _stringHashCacheLock.ExitUpgradeableReadLock ();
 119                         }
 120
 121                         return result;
 122                 }
 123
 124                 static void InitEmbeddedResourcesUrls (KeyedHashAlgorithm kha, Assembly assembly, string assemblyName, string assemblyHash, AssemblyEmbeddedResources entry)
 125                 {
 126                         WebResourceAttribute [] attrs = (WebResourceAttribute []) assembly.GetCustomAttributes (typeof (WebResourceAttribute), false);
 127                         WebResourceAttribute attr;
 128                         string apath = assembly.Location;
 129                         for (int i = 0; i < attrs.Length; i++) {
 130                                 attr = attrs [i];
 131                                 string resourceName = attr.WebResource;
 132                                 if (!String.IsNullOrEmpty (resourceName)) {
 133                                         string resourceNameHash = GetStringHash (kha, resourceName);
 134 #if SYSTEM_WEB_EXTENSIONS
 135                                         bool debug = resourceName.EndsWith (".debug.js", StringComparison.OrdinalIgnoreCase);
 136                                         string dbgTail = debug ? "d" : String.Empty;
 137                                         string rkNoNotify = resourceNameHash + "f" + dbgTail;
 138                                         string rkNotify = resourceNameHash + "t" + dbgTail;
 139
 140                                         if (!entry.Resources.ContainsKey (rkNoNotify)) {
 141                                                 var er = new EmbeddedResource () {
 142                                                         Name = resourceName,
 143                                                         Attribute = attr,
 144                                                         Url = CreateResourceUrl (kha, assemblyName, assemblyHash, apath, rkNoNotify, debug, false)
 145                                                 };
 146
 147                                                 entry.Resources.Add (rkNoNotify, er);
 148                                         }
 149
 150                                         if (!entry.Resources.ContainsKey (rkNotify)) {
 151                                                 var er = new EmbeddedResource () {
 152                                                         Name = resourceName,
 153                                                         Attribute = attr,
 154                                                         Url = CreateResourceUrl (kha, assemblyName, assemblyHash, apath, rkNotify, debug, true)
 155                                                 };
 156
 157                                                 entry.Resources.Add (rkNotify, er);
 158                                         }
 159 #else
 160                                         if (!entry.Resources.ContainsKey (resourceNameHash)) {
 161                                                 var er = new EmbeddedResource () {
 162                                                         Name = resourceName,
 163                                                         Attribute = attr,
 164                                                         Url = CreateResourceUrl (kha, assemblyName, assemblyHash, apath, resourceNameHash, false, false)
 165                                                 };
 166                                                 entry.Resources.Add (resourceNameHash, er);
 167                                         }
 168 #endif
 169                                 }
 170                         }
 171                 }
 172
 173 #if !SYSTEM_WEB_EXTENSIONS
 174                 internal static string GetResourceUrl (Type type, string resourceName)
 175                 {
 176                         return GetResourceUrl (type.Assembly, resourceName, false);
 177                 }
 178 #endif
 179                 static EmbeddedResource DecryptAssemblyResource (string val, out AssemblyEmbeddedResources entry)
 180                 {
 181                         entry = null;
 182
 183                         string[] parts = val.Split ('_');
 184                         if (parts.Length != 3)
 185                                 return null;
 186
 187                         Encoding enc = Encoding.UTF8;
 188                         string asmNameHash = parts [0];
 189                         string resNameHash = parts [1];
 190                         bool debug = parts [2] == "t";
 191
 192                         try {
 193                                 _embeddedResourcesLock.EnterReadLock ();
 194                                 if (!_embeddedResources.TryGetValue (asmNameHash, out entry) || entry == null)
 195                                         return null;
 196
 197                                 EmbeddedResource res;
 198                                 if (!entry.Resources.TryGetValue (resNameHash, out res) || res == null) {
 199 #if SYSTEM_WEB_EXTENSIONS
 200                                         if (!debug)
 201                                                 return null;
 202
 203                                         if (!entry.Resources.TryGetValue (resNameHash.Substring (0, resNameHash.Length - 1), out res))
 204                                                 return null;
 205 #else
 206                                         return null;
 207 #endif
 208                                 }
 209
 210                                 return res;
 211                         } finally {
 212                                 _embeddedResourcesLock.ExitReadLock ();
 213                         }
 214                 }
 215
 216                 internal static string GetResourceUrl (Assembly assembly, string resourceName, bool notifyScriptLoaded)
 217                 {
 218                         if (assembly == null)
 219                                 return String.Empty;
 220
 221                         KeyedHashAlgorithm kha = ReusableHashAlgorithm;
 222                         if (kha != null) {
 223                                 return GetResourceUrl (kha, assembly, resourceName, notifyScriptLoaded);
 224                         } else {
 225                                 MachineKeySection mks = MachineKeySection.Config;
 226                                 using (kha = MachineKeySectionUtils.GetValidationAlgorithm (mks)) {
 227                                         kha.Key = MachineKeySectionUtils.GetValidationKey (mks);
 228                                         return GetResourceUrl (kha, assembly, resourceName, notifyScriptLoaded);
 229                                 }
 230                         }
 231                 }
 232
 233                 static string GetResourceUrl (KeyedHashAlgorithm kha, Assembly assembly, string resourceName, bool notifyScriptLoaded)
 234                 {
 235                         string assemblyName = assembly == currAsm ? "s" : assembly.GetName ().FullName;
 236                         string assemblyNameHash = GetStringHash (kha, assemblyName);
 237                         string resourceNameHash = GetStringHash (kha, resourceName);
 238                         bool debug = false;
 239                         string url;
 240                         AssemblyEmbeddedResources entry;
 241
 242                         try {
 243                                 _embeddedResourcesLock.EnterUpgradeableReadLock ();
 244                                 if (!_embeddedResources.TryGetValue (assemblyNameHash, out entry) || entry == null) {
 245                                         try {
 246                                                 _embeddedResourcesLock.EnterWriteLock ();
 247                                                 entry = new AssemblyEmbeddedResources () {
 248                                                         AssemblyName = assemblyName
 249                                                 };
 250                                                 InitEmbeddedResourcesUrls (kha, assembly, assemblyName, assemblyNameHash, entry);
 251                                                 _embeddedResources.Add (assemblyNameHash, entry);
 252                                         } finally {
 253                                                 _embeddedResourcesLock.ExitWriteLock ();
 254                                         }
 255                                 }
 256                                 string lookupKey;
 257 #if SYSTEM_WEB_EXTENSIONS
 258                                 debug = resourceName.EndsWith (".debug.js", StringComparison.OrdinalIgnoreCase);
 259                                 string dbgTail = debug ? "d" : String.Empty;
 260                                 lookupKey = resourceNameHash + (notifyScriptLoaded ? "t" : "f") + dbgTail;
 261 #else
 262                                 lookupKey = resourceNameHash;
 263 #endif
 264                                 EmbeddedResource res;
 265                                 if (entry.Resources.TryGetValue (lookupKey, out res) && res != null)
 266                                         url = res.Url;
 267                                 else {
 268 #if SYSTEM_WEB_EXTENSIONS
 269                                         if (debug) {
 270                                                 resourceNameHash = GetStringHash (kha, resourceName.Substring (0, resourceName.Length - 9) + ".js");
 271                                                 lookupKey = resourceNameHash + (notifyScriptLoaded ? "t" : "f");
 272
 273                                                 if (entry.Resources.TryGetValue (lookupKey, out res) && res != null)
 274                                                         url = res.Url;
 275                                                 else
 276                                                         url = null;
 277                                         } else
 278 #endif
 279                                                 url = null;
 280                                 }
 281                         } finally {
 282                                 _embeddedResourcesLock.ExitUpgradeableReadLock ();
 283                         }
 284
 285                         if (url == null)
 286                                 url = CreateResourceUrl (kha, assemblyName, assemblyNameHash, assembly.Location, resourceNameHash, debug, notifyScriptLoaded);
 287
 288                         return url;
 289                 }
 290
 291                 static string CreateResourceUrl (KeyedHashAlgorithm kha, string assemblyName, string assemblyNameHash, string assemblyPath, string resourceNameHash, bool debug, bool notifyScriptLoaded)
 292                 {
 293                         string atime = String.Empty;
 294                         string extra = String.Empty;
 295 #if SYSTEM_WEB_EXTENSIONS
 296                         extra = QueryParamSeparator + "n=" + (notifyScriptLoaded ? "t" : "f");
 297 #endif
 298
 299 #if TARGET_JVM
 300                         atime = QueryParamSeparator + "t=" + assemblyName.GetHashCode ();
 301 #else
 302                         if (!String.IsNullOrEmpty (assemblyPath) && File.Exists (assemblyPath))
 303                                 atime = QueryParamSeparator + "t=" + File.GetLastWriteTimeUtc (assemblyPath).Ticks;
 304                         else
 305                                 atime = QueryParamSeparator + "t=" + DateTime.UtcNow.Ticks;
 306 #endif
 307                         string d = assemblyNameHash + "_" + resourceNameHash +  (debug ? "_t" : "_f");
 308                         string href = HandlerFileName + "?d=" + d + atime + extra;
 309                         HttpContext ctx = HttpContext.Current;
 310                         HttpRequest req = ctx != null ? ctx.Request : null;
 311                         if (req != null) {
 312                                 string appPath = VirtualPathUtility.AppendTrailingSlash (req.ApplicationPath);
 313                                 href = appPath + href;
 314                         }
 315
 316                         return href;
 317                 }
 318
 319 #if SYSTEM_WEB_EXTENSIONS
 320                 protected virtual void ProcessRequest (HttpContext context)
 321 #else
 322                 void System.Web.IHttpHandler.ProcessRequest (HttpContext context)
 323 #endif
 324                 {
 325                         HttpRequest request = context.Request;
 326                         // val is URL-encoded, which means every + has been replaced with ' ', we
 327                         // need to revert that or the base64 conversion will fail.
 328                         string d = request.QueryString ["d"];
 329                         if (!String.IsNullOrEmpty (d))
 330                                 d = d.Replace (' ', '+');
 331
 332                         AssemblyEmbeddedResources entry;
 333                         EmbeddedResource res = DecryptAssemblyResource (d, out entry);
 334                         WebResourceAttribute wra = res != null ? res.Attribute : null;
 335                         if (wra == null)
 336                                 throw new HttpException (404, "Resource not found");
 337
 338                         Assembly assembly;
 339                         if (entry.AssemblyName == "s")
 340                                 assembly = currAsm;
 341                         else
 342                                 assembly = Assembly.Load (entry.AssemblyName);
 343
 344                         HttpResponse response = context.Response;
 345                         string req_cache = request.Headers ["Cache-Control"];
 346                         if (String.Compare (req_cache, "max-age=0", StringComparison.Ordinal) == 0) {
 347                                 long atime;
 348                                 if (Int64.TryParse (request.QueryString ["t"], out atime)) {
 349                                         if (atime == File.GetLastWriteTimeUtc (assembly.Location).Ticks) {
 350                                                 response.Clear ();
 351                                                 response.StatusCode = 304;
 352                                                 response.ContentType = null;
 353                                                 response.CacheControl = "public"; // easier to set it to public as MS than remove it
 354                                                 context.ApplicationInstance.CompleteRequest ();
 355                                                 return;
 356                                         }
 357                                 }
 358                         }
 359                         string modif_since = request.Headers ["If-Modified-Since"];
 360                         if (!String.IsNullOrEmpty (modif_since)) {
 361                                 try {
 362                                         DateTime modif;
 363                                         if (DateTime.TryParseExact (modif_since, "r", null, 0, out modif)) {
 364                                                 if (File.GetLastWriteTimeUtc (assembly.Location) <= modif) {
 365                                                         response.Clear ();
 366                                                         response.StatusCode = 304;
 367                                                         response.ContentType = null;
 368                                                         response.CacheControl = "public"; // easier to set it to public as MS than remove it
 369                                                         context.ApplicationInstance.CompleteRequest ();
 370                                                         return;
 371                                                 }
 372                                         }
 373                                 } catch {}
 374                         }
 375
 376                         response.ContentType = wra.ContentType;
 377
 378                         DateTime utcnow = DateTime.UtcNow;
 379                         response.Headers.Add ("Last-Modified", utcnow.ToString ("r"));
 380                         response.ExpiresAbsolute = utcnow.AddYears (1);
 381                         response.CacheControl = "public";
 382
 383                         Stream s = assembly.GetManifestResourceStream (res.Name);
 384                         if (s == null)
 385                                 throw new HttpException (404, "Resource " + res.Name + " not found");
 386
 387                         if (wra.PerformSubstitution) {
 388                                 using (StreamReader r = new StreamReader (s)) {
 389                                         TextWriter w = response.Output;
 390                                         new PerformSubstitutionHelper (assembly).PerformSubstitution (r, w);
 391                                 }
 392                         } else if (response.OutputStream is HttpResponseStream) {
 393                                 UnmanagedMemoryStream st = (UnmanagedMemoryStream) s;
 394                                 HttpResponseStream hstream = (HttpResponseStream) response.OutputStream;
 395                                 unsafe {
 396                                         hstream.WritePtr (new IntPtr (st.PositionPointer), (int) st.Length);
 397                                 }
 398                         } else {
 399                                 byte [] buf = new byte [1024];
 400                                 Stream output = response.OutputStream;
 401                                 int c;
 402                                 do {
 403                                         c = s.Read (buf, 0, 1024);
 404                                         output.Write (buf, 0, c);
 405                                 } while (c > 0);
 406                         }
 407 #if SYSTEM_WEB_EXTENSIONS
 408                         TextWriter writer = response.Output;
 409                         foreach (ScriptResourceAttribute sra in assembly.GetCustomAttributes (typeof (ScriptResourceAttribute), false)) {
 410                                 if (String.Compare (sra.ScriptName, res.Name, StringComparison.Ordinal) == 0) {
 411                                         string scriptResourceName = sra.ScriptResourceName;
 412                                         ResourceSet rset = null;
 413                                         try {
 414                                                 rset = new ResourceManager (scriptResourceName, assembly).GetResourceSet (Threading.Thread.CurrentThread.CurrentUICulture, true, true);
 415                                         }
 416                                         catch (MissingManifestResourceException) {
 417 #if TARGET_JVM // GetResourceSet does not throw  MissingManifestResourceException if ressource is not exists
 418                                         }
 419                                         if (rset == null) {
 420 #endif
 421                                                 if (scriptResourceName.EndsWith (".resources")) {
 422                                                         scriptResourceName = scriptResourceName.Substring (0, scriptResourceName.Length - 10);
 423                                                         rset = new ResourceManager (scriptResourceName, assembly).GetResourceSet (Threading.Thread.CurrentThread.CurrentUICulture, true, true);
 424                                                 }
 425 #if !TARGET_JVM
 426                                                 else
 427                                                         throw;
 428 #endif
 429                                         }
 430                                         if (rset == null)
 431                                                 break;
 432                                         writer.WriteLine ();
 433                                         string ns = sra.TypeName;
 434                                         int indx = ns.LastIndexOf ('.');
 435                                         if (indx > 0)
 436                                                 writer.WriteLine ("Type.registerNamespace('" + ns.Substring (0, indx) + "')");
 437                                         writer.Write ("{0}={{", sra.TypeName);
 438                                         bool first = true;
 439                                         foreach (DictionaryEntry de in rset) {
 440                                                 string value = de.Value as string;
 441                                                 if (value != null) {
 442                                                         if (first)
 443                                                                 first = false;
 444                                                         else
 445                                                                 writer.Write (',');
 446                                                         writer.WriteLine ();
 447                                                         writer.Write ("{0}:{1}", GetScriptStringLiteral ((string) de.Key), GetScriptStringLiteral (value));
 448                                                 }
 449                                         }
 450                                         writer.WriteLine ();
 451                                         writer.WriteLine ("};");
 452                                         break;
 453                                 }
 454                         }
 455
 456                         bool notifyScriptLoaded = request.QueryString ["n"] == "t";
 457                         if (notifyScriptLoaded) {
 458                                 writer.WriteLine ();
 459                                 writer.WriteLine ("if(typeof(Sys)!=='undefined')Sys.Application.notifyScriptLoaded();");
 460                         }
 461 #endif
 462                 }
 463
 464                 sealed class PerformSubstitutionHelper
 465                 {
 466                         readonly Assembly _assembly;
 467                         static readonly Regex _regex = new Regex (@"\<%=[ ]*WebResource[ ]*\([ ]*""([^""]+)""[ ]*\)[ ]*%\>");
 468
 469                         public PerformSubstitutionHelper (Assembly assembly) {
 470                                 _assembly = assembly;
 471                         }
 472
 473                         public void PerformSubstitution (TextReader reader, TextWriter writer) {
 474                                 string line = reader.ReadLine ();
 475                                 while (line != null) {
 476                                         if (line.Length > 0 && _regex.IsMatch (line))
 477                                                 line = _regex.Replace (line, new MatchEvaluator (PerformSubstitutionReplace));
 478                                         writer.WriteLine (line);
 479                                         line = reader.ReadLine ();
 480                                 }
 481                         }
 482
 483                         string PerformSubstitutionReplace (Match m) {
 484                                 string resourceName = m.Groups [1].Value;
 485 #if SYSTEM_WEB_EXTENSIONS
 486                                 return ScriptResourceHandler.GetResourceUrl (_assembly, resourceName, false);
 487 #else
 488                                 return AssemblyResourceLoader.GetResourceUrl (_assembly, resourceName, false);
 489 #endif
 490                         }
 491                 }
 492
 493 #if !SYSTEM_WEB_EXTENSIONS
 494                 bool System.Web.IHttpHandler.IsReusable { get { return true; } }
 495 #endif
 496                 sealed class EmbeddedResource
 497                 {
 498                         public string Name;
 499                         public string Url;
 500                         public WebResourceAttribute Attribute;
 501                 }
 502
 503                 sealed class AssemblyEmbeddedResources
 504                 {
 505                         public string AssemblyName = String.Empty;
 506                         public Dictionary <string, EmbeddedResource> Resources = new Dictionary <string, EmbeddedResource> (StringComparer.Ordinal);
 507                 }
 508         }
 509 }
 510