class/System/System.Net/ServicePointManager.cs

   1 //
   2 // System.Net.ServicePointManager
   3 //
   4 // Author:
   5 //   Lawrence Pit (loz@cable.a2000.nl)
   6 //
   7
   8 //
   9 // Permission is hereby granted, free of charge, to any person obtaining
  10 // a copy of this software and associated documentation files (the
  11 // "Software"), to deal in the Software without restriction, including
  12 // without limitation the rights to use, copy, modify, merge, publish,
  13 // distribute, sublicense, and/or sell copies of the Software, and to
  14 // permit persons to whom the Software is furnished to do so, subject to
  15 // the following conditions:
  16 //
  17 // The above copyright notice and this permission notice shall be
  18 // included in all copies or substantial portions of the Software.
  19 //
  20 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  21 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  22 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  23 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  24 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  25 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  26 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  27 //
  28
  29 using System;
  30 using System.Collections;
  31 using System.Collections.Specialized;
  32 using System.Configuration;
  33 using System.Net.Configuration;
  34 using System.Security.Cryptography.X509Certificates;
  35
  36 #if NET_2_0
  37 using System.Net.Security;
  38 #endif
  39
  40 //
  41 // notes:
  42 // A service point manager manages service points (duh!).
  43 // A service point maintains a list of connections (per scheme + authority).
  44 // According to HttpWebRequest.ConnectionGroupName each connection group
  45 // creates additional connections. therefor, a service point has a hashtable
  46 // of connection groups where each value is a list of connections.
  47 //
  48 // when we need to make an HttpWebRequest, we need to do the following:
  49 // 1. find service point, given Uri and Proxy
  50 // 2. find connection group, given service point and group name
  51 // 3. find free connection in connection group, or create one (if ok due to limits)
  52 // 4. lease connection
  53 // 5. execute request
  54 // 6. when finished, return connection
  55 //
  56
  57
  58 namespace System.Net
  59 {
  60         public class ServicePointManager
  61         {
  62                 class SPKey {
  63                         Uri uri; // schema/host/port
  64                         bool use_connect;
  65
  66                         public SPKey (Uri uri, bool use_connect) {
  67                                 this.uri = uri;
  68                                 this.use_connect = use_connect;
  69                         }
  70
  71                         public Uri Uri {
  72                                 get { return uri; }
  73                         }
  74
  75                         public bool UseConnect {
  76                                 get { return use_connect; }
  77                         }
  78
  79                         public override int GetHashCode () {
  80                                 return uri.GetHashCode () + ((use_connect) ? 1 : 0);
  81                         }
  82
  83                         public override bool Equals (object obj) {
  84                                 SPKey other = obj as SPKey;
  85                                 if (obj == null) {
  86                                         return false;
  87                                 }
  88
  89                                 return (uri.Equals (other.uri) && other.use_connect == use_connect);
  90                         }
  91                 }
  92
  93                 private static HybridDictionary servicePoints = new HybridDictionary ();
  94
  95                 // Static properties
  96
  97                 private static ICertificatePolicy policy = new DefaultCertificatePolicy ();
  98                 private static int defaultConnectionLimit = DefaultPersistentConnectionLimit;
  99                 private static int maxServicePointIdleTime = 900000; // 15 minutes
 100                 private static int maxServicePoints = 0;
 101                 private static bool _checkCRL = false;
 102                 private static SecurityProtocolType _securityProtocol = SecurityProtocolType.Ssl3 | SecurityProtocolType.Tls;
 103
 104 #if NET_1_1
 105 #if TARGET_JVM
 106                 static bool expectContinue = false;
 107 #else
 108                 static bool expectContinue = true;
 109 #endif
 110                 static bool useNagle;
 111 #endif
 112 #if NET_2_0
 113                 static RemoteCertificateValidationCallback server_cert_cb;
 114 #endif
 115
 116                 // Fields
 117
 118                 public const int DefaultNonPersistentConnectionLimit = 4;
 119                 public const int DefaultPersistentConnectionLimit = 2;
 120
 121 #if !MONOTOUCH
 122                 const string configKey = "system.net/connectionManagement";
 123                 static ConnectionManagementData manager;
 124 #endif
 125
 126                 static ServicePointManager ()
 127                 {
 128 #if !MONOTOUCH
 129 #if NET_2_0 && CONFIGURATION_DEP
 130                         object cfg = ConfigurationManager.GetSection (configKey);
 131                         ConnectionManagementSection s = cfg as ConnectionManagementSection;
 132                         if (s != null) {
 133                                 manager = new ConnectionManagementData (null);
 134                                 foreach (ConnectionManagementElement e in s.ConnectionManagement)
 135                                         manager.Add (e.Address, e.MaxConnection);
 136
 137                                 defaultConnectionLimit = (int) manager.GetMaxConnections ("*");
 138                                 return;
 139                         }
 140 #endif
 141                         manager = (ConnectionManagementData) ConfigurationSettings.GetConfig (configKey);
 142                         if (manager != null) {
 143                                 defaultConnectionLimit = (int) manager.GetMaxConnections ("*");
 144                         }
 145 #endif
 146                 }
 147
 148                 // Constructors
 149                 private ServicePointManager ()
 150                 {
 151                 }
 152
 153                 // Properties
 154
 155 #if NET_2_0
 156                 [Obsolete ("Use ServerCertificateValidationCallback instead",
 157                            false)]
 158 #endif
 159                 public static ICertificatePolicy CertificatePolicy {
 160                         get { return policy; }
 161                         set { policy = value; }
 162                 }
 163
 164 #if NET_1_0
 165                 // we need it for SslClientStream
 166                 internal
 167 #else
 168                 [MonoTODO("CRL checks not implemented")]
 169                 public
 170 #endif
 171                 static bool CheckCertificateRevocationList {
 172                         get { return _checkCRL; }
 173                         set { _checkCRL = false; }      // TODO - don't yet accept true
 174                 }
 175
 176                 public static int DefaultConnectionLimit {
 177                         get { return defaultConnectionLimit; }
 178                         set {
 179                                 if (value <= 0)
 180                                         throw new ArgumentOutOfRangeException ("value");
 181
 182                                 defaultConnectionLimit = value;
 183                         }
 184                 }
 185
 186 #if NET_2_0
 187                 static Exception GetMustImplement ()
 188                 {
 189                         return new NotImplementedException ();
 190                 }
 191
 192                 [MonoTODO]
 193                 public static int DnsRefreshTimeout
 194                 {
 195                         get {
 196                                 throw GetMustImplement ();
 197                         }
 198                         set {
 199                                 throw GetMustImplement ();
 200                         }
 201                 }
 202
 203                 [MonoTODO]
 204                 public static bool EnableDnsRoundRobin
 205                 {
 206                         get {
 207                                 throw GetMustImplement ();
 208                         }
 209                         set {
 210                                 throw GetMustImplement ();
 211                         }
 212                 }
 213 #endif
 214
 215                 public static int MaxServicePointIdleTime {
 216                         get {
 217                                 return maxServicePointIdleTime;
 218                         }
 219                         set {
 220                                 if (value < -2 || value > Int32.MaxValue)
 221                                         throw new ArgumentOutOfRangeException ("value");
 222                                 maxServicePointIdleTime = value;
 223                         }
 224                 }
 225
 226                 public static int MaxServicePoints {
 227                         get {
 228                                 return maxServicePoints;
 229                         }
 230                         set {
 231                                 if (value < 0)
 232                                         throw new ArgumentException ("value");
 233
 234                                 maxServicePoints = value;
 235                                 RecycleServicePoints ();
 236                         }
 237                 }
 238
 239 #if NET_1_0
 240                 // we need it for SslClientStream
 241                 internal
 242 #else
 243                 public
 244 #endif
 245                 static SecurityProtocolType SecurityProtocol {
 246                         get { return _securityProtocol; }
 247                         set { _securityProtocol = value; }
 248                 }
 249
 250 #if NET_2_0
 251                 public static RemoteCertificateValidationCallback ServerCertificateValidationCallback
 252                 {
 253                         get {
 254                                 return server_cert_cb;
 255                         }
 256                         set {
 257                                 server_cert_cb = value;
 258                         }
 259                 }
 260 #endif
 261
 262 #if NET_1_1
 263                 public static bool Expect100Continue {
 264                         get { return expectContinue; }
 265                         set { expectContinue = value; }
 266                 }
 267
 268                 public static bool UseNagleAlgorithm {
 269                         get { return useNagle; }
 270                         set { useNagle = value; }
 271                 }
 272 #endif
 273                 // Methods
 274
 275                 public static ServicePoint FindServicePoint (Uri address)
 276                 {
 277                         return FindServicePoint (address, GlobalProxySelection.Select);
 278                 }
 279
 280                 public static ServicePoint FindServicePoint (string uriString, IWebProxy proxy)
 281                 {
 282                         return FindServicePoint (new Uri(uriString), proxy);
 283                 }
 284
 285                 public static ServicePoint FindServicePoint (Uri address, IWebProxy proxy)
 286                 {
 287                         if (address == null)
 288                                 throw new ArgumentNullException ("address");
 289
 290                         RecycleServicePoints ();
 291
 292                         bool usesProxy = false;
 293                         bool useConnect = false;
 294                         if (proxy != null && !proxy.IsBypassed(address)) {
 295                                 usesProxy = true;
 296                                 bool isSecure = address.Scheme == "https";
 297                                 address = proxy.GetProxy (address);
 298                                 if (address.Scheme != "http" && !isSecure)
 299                                         throw new NotSupportedException ("Proxy scheme not supported.");
 300
 301                                 if (isSecure && address.Scheme == "http")
 302                                         useConnect = true;
 303                         }
 304
 305                         address = new Uri (address.Scheme + "://" + address.Authority);
 306
 307                         ServicePoint sp = null;
 308                         lock (servicePoints) {
 309                                 SPKey key = new SPKey (address, useConnect);
 310                                 sp = servicePoints [key] as ServicePoint;
 311                                 if (sp != null)
 312                                         return sp;
 313
 314                                 if (maxServicePoints > 0 && servicePoints.Count >= maxServicePoints)
 315                                         throw new InvalidOperationException ("maximum number of service points reached");
 316
 317                                 string addr = address.ToString ();
 318 #if MONOTOUCH
 319                                 int limit = defaultConnectionLimit;
 320 #else
 321                                 int limit = (int) manager.GetMaxConnections (addr);
 322 #endif
 323                                 sp = new ServicePoint (address, limit, maxServicePointIdleTime);
 324 #if NET_1_1
 325                                 sp.Expect100Continue = expectContinue;
 326                                 sp.UseNagleAlgorithm = useNagle;
 327 #endif
 328                                 sp.UsesProxy = usesProxy;
 329                                 sp.UseConnect = useConnect;
 330                                 servicePoints.Add (key, sp);
 331                         }
 332
 333                         return sp;
 334                 }
 335
 336                 // Internal Methods
 337
 338                 internal static void RecycleServicePoints ()
 339                 {
 340                         ArrayList toRemove = new ArrayList ();
 341                         lock (servicePoints) {
 342                                 IDictionaryEnumerator e = servicePoints.GetEnumerator ();
 343                                 while (e.MoveNext ()) {
 344                                         ServicePoint sp = (ServicePoint) e.Value;
 345                                         if (sp.AvailableForRecycling) {
 346                                                 toRemove.Add (e.Key);
 347                                         }
 348                                 }
 349
 350                                 for (int i = 0; i < toRemove.Count; i++)
 351                                         servicePoints.Remove (toRemove [i]);
 352
 353                                 if (maxServicePoints == 0 || servicePoints.Count <= maxServicePoints)
 354                                         return;
 355
 356                                 // get rid of the ones with the longest idle time
 357                                 SortedList list = new SortedList (servicePoints.Count);
 358                                 e = servicePoints.GetEnumerator ();
 359                                 while (e.MoveNext ()) {
 360                                         ServicePoint sp = (ServicePoint) e.Value;
 361                                         if (sp.CurrentConnections == 0) {
 362                                                 while (list.ContainsKey (sp.IdleSince))
 363                                                         sp.IdleSince = sp.IdleSince.AddMilliseconds (1);
 364                                                 list.Add (sp.IdleSince, sp.Address);
 365                                         }
 366                                 }
 367
 368                                 for (int i = 0; i < list.Count && servicePoints.Count > maxServicePoints; i++)
 369                                         servicePoints.Remove (list.GetByIndex (i));
 370                         }
 371                 }
 372         }
 373 }