mcs/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 //
  37 // notes:
  38 // A service point manager manages service points (duh!).
  39 // A service point maintains a list of connections (per scheme + authority).
  40 // According to HttpWebRequest.ConnectionGroupName each connection group
  41 // creates additional connections. therefor, a service point has a hashtable
  42 // of connection groups where each value is a list of connections.
  43 //
  44 // when we need to make an HttpWebRequest, we need to do the following:
  45 // 1. find service point, given Uri and Proxy
  46 // 2. find connection group, given service point and group name
  47 // 3. find free connection in connection group, or create one (if ok due to limits)
  48 // 4. lease connection
  49 // 5. execute request
  50 // 6. when finished, return connection
  51 //
  52
  53
  54 namespace System.Net
  55 {
  56         public class ServicePointManager
  57         {
  58                 private static HybridDictionary servicePoints = new HybridDictionary ();
  59
  60                 // Static properties
  61
  62                 private static ICertificatePolicy policy = new DefaultCertificatePolicy ();
  63                 private static int defaultConnectionLimit = DefaultPersistentConnectionLimit;
  64                 private static int maxServicePointIdleTime = 900000; // 15 minutes
  65                 private static int maxServicePoints = 0;
  66                 private static bool _checkCRL = false;
  67 #if (NET_1_0 || NET_1_1)
  68                 private static SecurityProtocolType _securityProtocol = SecurityProtocolType.Ssl3;
  69 #else
  70                 private static SecurityProtocolType _securityProtocol = SecurityProtocolType.Default;
  71 #endif
  72 #if NET_1_1
  73                 static bool expectContinue = true;
  74                 static bool useNagle;
  75 #endif
  76
  77                 // Fields
  78
  79                 public const int DefaultNonPersistentConnectionLimit = 4;
  80                 public const int DefaultPersistentConnectionLimit = 2;
  81
  82                 const string configKey = "system.net/connectionManagement";
  83                 static ConnectionManagementData manager;
  84
  85                 static ServicePointManager ()
  86                 {
  87                         manager = (ConnectionManagementData) ConfigurationSettings.GetConfig (configKey);
  88                 }
  89                 // Constructors
  90                 private ServicePointManager ()
  91                 {
  92                 }
  93
  94                 // Properties
  95
  96                 public static ICertificatePolicy CertificatePolicy {
  97                         get { return policy; }
  98                         set { policy = value; }
  99                 }
 100
 101 #if NET_1_0
 102                 // we need it for SslClientStream
 103                 internal
 104 #else
 105                 [MonoTODO("CRL checks not implemented")]
 106                 public
 107 #endif
 108                 static bool CheckCertificateRevocationList {
 109                         get { return _checkCRL; }
 110                         set { _checkCRL = false; }      // TODO - don't yet accept true
 111                 }
 112
 113                 public static int DefaultConnectionLimit {
 114                         get { return defaultConnectionLimit; }
 115                         set {
 116                                 if (value <= 0)
 117                                         throw new ArgumentOutOfRangeException ("value");
 118
 119                                 defaultConnectionLimit = value;
 120                         }
 121                 }
 122
 123                 public static int MaxServicePointIdleTime {
 124                         get {
 125                                 return maxServicePointIdleTime;
 126                         }
 127                         set {
 128                                 if (value < -2 || value > Int32.MaxValue)
 129                                         throw new ArgumentOutOfRangeException ("value");
 130                                 maxServicePointIdleTime = value;
 131                         }
 132                 }
 133
 134                 public static int MaxServicePoints {
 135                         get {
 136                                 return maxServicePoints;
 137                         }
 138                         set {
 139                                 if (value < 0)
 140                                         throw new ArgumentException ("value");
 141
 142                                 maxServicePoints = value;
 143                                 RecycleServicePoints ();
 144                         }
 145                 }
 146
 147 #if NET_1_0
 148                 // we need it for SslClientStream
 149                 internal
 150 #else
 151                 public
 152 #endif
 153                 static SecurityProtocolType SecurityProtocol {
 154                         get { return _securityProtocol; }
 155                         set { _securityProtocol = value; }
 156                 }
 157
 158 #if NET_1_1
 159                 public static bool Expect100Continue {
 160                         get { return expectContinue; }
 161                         set { expectContinue = value; }
 162                 }
 163
 164                 public static bool UseNagleAlgorithm {
 165                         get { return useNagle; }
 166                         set { useNagle = value; }
 167                 }
 168 #endif
 169                 // Methods
 170
 171                 public static ServicePoint FindServicePoint (Uri address)
 172                 {
 173                         return FindServicePoint (address, GlobalProxySelection.Select);
 174                 }
 175
 176                 public static ServicePoint FindServicePoint (string uriString, IWebProxy proxy)
 177                 {
 178                         return FindServicePoint (new Uri(uriString), proxy);
 179                 }
 180
 181                 public static ServicePoint FindServicePoint (Uri address, IWebProxy proxy)
 182                 {
 183                         if (address == null)
 184                                 throw new ArgumentNullException ("address");
 185
 186                         RecycleServicePoints ();
 187
 188                         bool usesProxy = false;
 189                         bool useConnect = false;
 190                         if (proxy != null && !proxy.IsBypassed(address)) {
 191                                 usesProxy = true;
 192                                 bool isSecure = address.Scheme == "https";
 193                                 address = proxy.GetProxy (address);
 194                                 if (address.Scheme != "http" && !isSecure)
 195                                         throw new NotSupportedException ("Proxy scheme not supported.");
 196
 197                                 if (isSecure && address.Scheme == "http")
 198                                         useConnect = true;
 199                         }
 200
 201                         address = new Uri (address.Scheme + "://" + address.Authority);
 202
 203                         ServicePoint sp = null;
 204                         lock (servicePoints) {
 205                                 sp = servicePoints [address] as ServicePoint;
 206                                 if (sp != null)
 207                                         return sp;
 208
 209                                 if (maxServicePoints > 0 && servicePoints.Count >= maxServicePoints)
 210                                         throw new InvalidOperationException ("maximum number of service points reached");
 211
 212                                 string addr = address.ToString ();
 213                                 int limit = (int) manager.GetMaxConnections (addr);
 214                                 sp = new ServicePoint (address, limit, maxServicePointIdleTime);
 215 #if NET_1_1
 216                                 sp.Expect100Continue = expectContinue;
 217                                 sp.UseNagleAlgorithm = useNagle;
 218 #endif
 219                                 sp.UsesProxy = usesProxy;
 220                                 sp.UseConnect = useConnect;
 221                                 servicePoints.Add (address, sp);
 222                         }
 223
 224                         return sp;
 225                 }
 226
 227                 // Internal Methods
 228
 229                 internal static void RecycleServicePoints ()
 230                 {
 231                         ArrayList toRemove = new ArrayList ();
 232                         lock (servicePoints) {
 233                                 IDictionaryEnumerator e = servicePoints.GetEnumerator ();
 234                                 while (e.MoveNext ()) {
 235                                         ServicePoint sp = (ServicePoint) e.Value;
 236                                         if (sp.AvailableForRecycling) {
 237                                                 toRemove.Add (e.Key);
 238                                         }
 239                                 }
 240
 241                                 for (int i = 0; i < toRemove.Count; i++)
 242                                         servicePoints.Remove (toRemove [i]);
 243
 244                                 if (maxServicePoints == 0 || servicePoints.Count <= maxServicePoints)
 245                                         return;
 246
 247                                 // get rid of the ones with the longest idle time
 248                                 SortedList list = new SortedList (servicePoints.Count);
 249                                 e = servicePoints.GetEnumerator ();
 250                                 while (e.MoveNext ()) {
 251                                         ServicePoint sp = (ServicePoint) e.Value;
 252                                         if (sp.CurrentConnections == 0) {
 253                                                 while (list.ContainsKey (sp.IdleSince))
 254                                                         sp.IdleSince.AddMilliseconds (1);
 255                                                 list.Add (sp.IdleSince, sp.Address);
 256                                         }
 257                                 }
 258
 259                                 for (int i = 0; i < list.Count && servicePoints.Count > maxServicePoints; i++)
 260                                         servicePoints.Remove (list.GetByIndex (i));
 261                         }
 262                 }
 263         }
 264 }