mcs/class/System.Net/System.Net.Policy/CrossDomainPolicyManager.cs

   1 //
   2 // CrossDomainPolicyManager.cs
   3 //
   4 // Authors:
   5 //      Atsushi Enomoto <atsushi@ximian.com>
   6 //      Moonlight List (moonlight-list@lists.ximian.com)
   7 //
   8 // Copyright (C) 2009-2010 Novell, Inc.  http://www.novell.com
   9 //
  10 // Permission is hereby granted, free of charge, to any person obtaining
  11 // a copy of this software and associated documentation files (the
  12 // "Software"), to deal in the Software without restriction, including
  13 // without limitation the rights to use, copy, modify, merge, publish,
  14 // distribute, sublicense, and/or sell copies of the Software, and to
  15 // permit persons to whom the Software is furnished to do so, subject to
  16 // the following conditions:
  17 //
  18 // The above copyright notice and this permission notice shall be
  19 // included in all copies or substantial portions of the Software.
  20 //
  21 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  22 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  23 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  24 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  25 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  26 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  27 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  28 //
  29
  30 #if NET_2_1
  31
  32 using System;
  33 using System.Collections.Generic;
  34 using System.IO;
  35 using System.Net.Sockets;
  36 using System.Reflection;
  37 using System.Security;
  38 using System.Text;
  39 using System.Threading;
  40
  41 namespace System.Net.Policy {
  42
  43         internal static class CrossDomainPolicyManager {
  44
  45                 public static string GetRoot (Uri uri)
  46                 {
  47                         if ((uri.Scheme == "http" && uri.Port == 80) || (uri.Scheme == "https" && uri.Port == 443) || (uri.Port == -1))
  48                                 return String.Format ("{0}://{1}/", uri.Scheme, uri.DnsSafeHost);
  49                         else
  50                                 return String.Format ("{0}://{1}:{2}/", uri.Scheme, uri.DnsSafeHost, uri.Port);
  51                 }
  52 #if !TEST
  53                 public const string ClientAccessPolicyFile = "/clientaccesspolicy.xml";
  54                 public const string CrossDomainFile = "/crossdomain.xml";
  55
  56                 const int Timeout = 10000;
  57
  58                 // Web Access Policy
  59
  60                 static Dictionary<string,ICrossDomainPolicy> policies = new Dictionary<string,ICrossDomainPolicy> ();
  61
  62                 static internal ICrossDomainPolicy PolicyDownloadPolicy = new PolicyDownloadPolicy ();
  63                 static ICrossDomainPolicy site_of_origin_policy = new SiteOfOriginPolicy ();
  64                 static ICrossDomainPolicy no_access_policy = new NoAccessPolicy ();
  65
  66                 static Uri GetRootUri (Uri uri)
  67                 {
  68                         return new Uri (GetRoot (uri));
  69                 }
  70
  71                 public static Uri GetSilverlightPolicyUri (Uri uri)
  72                 {
  73                         return new Uri (GetRootUri (uri), CrossDomainPolicyManager.ClientAccessPolicyFile);
  74                 }
  75
  76                 public static Uri GetFlashPolicyUri (Uri uri)
  77                 {
  78                         return new Uri (GetRootUri (uri), CrossDomainPolicyManager.CrossDomainFile);
  79                 }
  80
  81                 public static ICrossDomainPolicy GetCachedWebPolicy (Uri uri)
  82                 {
  83                         // if we request an Uri from the same site then we return an "always positive" policy
  84                         if (SiteOfOriginPolicy.HasSameOrigin (uri, BaseDomainPolicy.ApplicationUri))
  85                                 return site_of_origin_policy;
  86
  87                         // otherwise we search for an already downloaded policy for the web site
  88                         string root = GetRoot (uri);
  89                         ICrossDomainPolicy policy = null;
  90                         policies.TryGetValue (root, out policy);
  91                         // and we return it (if we have it) or null (if we dont)
  92                         return policy;
  93                 }
  94
  95                 private static void AddPolicy (Uri responseUri, ICrossDomainPolicy policy)
  96                 {
  97                         string root = GetRoot (responseUri);
  98                         policies [root] = policy;
  99                 }
 100
 101                 // see moon/test/2.0/WebPolicies/Pages.xaml.cs for all test cases
 102                 private static bool CheckContentType (string contentType)
 103                 {
 104                         const string application_xml = "application/xml";
 105
 106                         // most common case: all text/* are accepted
 107                         if (contentType.StartsWith ("text/"))
 108                                 return true;
 109
 110                         // special case (e.g. used in nbcolympics)
 111                         if (contentType.StartsWith (application_xml)) {
 112                                 if (application_xml.Length == contentType.Length)
 113                                         return true; // exact match
 114
 115                                 // e.g. "application/xml; charset=x" - we do not care what comes after ';'
 116                                 if (contentType.Length > application_xml.Length)
 117                                         return contentType [application_xml.Length] == ';';
 118                         }
 119                         return false;
 120                 }
 121
 122                 public static ICrossDomainPolicy BuildSilverlightPolicy (HttpWebResponse response)
 123                 {
 124                         // return null if no Silverlight policy was found, since we offer a second chance with a flash policy
 125                         if ((response.StatusCode != HttpStatusCode.OK) || !CheckContentType (response.ContentType))
 126                                 return null;
 127
 128                         ICrossDomainPolicy policy = null;
 129                         try {
 130                                 policy = ClientAccessPolicy.FromStream (response.GetResponseStream ());
 131                                 if (policy != null)
 132                                         AddPolicy (response.ResponseUri, policy);
 133                         } catch (Exception ex) {
 134                                 Console.WriteLine (String.Format ("CrossDomainAccessManager caught an exception while reading {0}: {1}",
 135                                         response.ResponseUri, ex));
 136                                 // and ignore.
 137                         }
 138                         return policy;
 139                 }
 140
 141                 public static ICrossDomainPolicy BuildFlashPolicy (HttpWebResponse response)
 142                 {
 143                         ICrossDomainPolicy policy = null;
 144                         if ((response.StatusCode == HttpStatusCode.OK) && CheckContentType (response.ContentType)) {
 145                                 try {
 146                                         policy = FlashCrossDomainPolicy.FromStream (response.GetResponseStream ());
 147                                 } catch (Exception ex) {
 148                                         Console.WriteLine (String.Format ("CrossDomainAccessManager caught an exception while reading {0}: {1}",
 149                                                 response.ResponseUri, ex));
 150                                         // and ignore.
 151                                 }
 152                                 if (policy != null) {
 153                                         // see DRT# 864 and 865
 154                                         string site_control = response.Headers ["X-Permitted-Cross-Domain-Policies"];
 155                                         if (!String.IsNullOrEmpty (site_control))
 156                                                 (policy as FlashCrossDomainPolicy).SiteControl = site_control;
 157                                 }
 158                         }
 159
 160                         // the flash policy was the last chance, keep a NoAccess into the cache
 161                         if (policy == null)
 162                                 policy = no_access_policy;
 163
 164                         AddPolicy (response.ResponseUri, policy);
 165                         return policy;
 166                 }
 167
 168                 // Socket Policy
 169                 //
 170                 // - we connect once to a site for the entire application life time
 171                 // - this returns us a policy file (silverlight format only) or else no access is granted
 172                 // - this policy file
 173                 //      - can contain multiple policies
 174                 //      - can apply to multiple domains
 175                 //      - can grant access to several resources
 176
 177                 static Dictionary<string,ClientAccessPolicy> socket_policies = new Dictionary<string,ClientAccessPolicy> ();
 178                 static byte [] socket_policy_file_request = Encoding.UTF8.GetBytes ("<policy-file-request/>");
 179                 const int PolicyPort = 943;
 180
 181                 // make sure this work in a IPv6-only environment
 182                 static AddressFamily GetBestFamily ()
 183                 {
 184                         if (Socket.OSSupportsIPv4)
 185                                 return AddressFamily.InterNetwork;
 186                         else if (Socket.OSSupportsIPv6)
 187                                 return AddressFamily.InterNetworkV6;
 188                         else
 189                                 return AddressFamily.Unspecified;
 190                 }
 191
 192                 static Stream GetPolicyStream (IPEndPoint endpoint)
 193                 {
 194                         MemoryStream ms = new MemoryStream ();
 195                         ManualResetEvent mre = new ManualResetEvent (false);
 196                         // Silverlight only support TCP
 197                         Socket socket = new Socket (GetBestFamily (), SocketType.Stream, ProtocolType.Tcp);
 198
 199                         // Application code can't connect to port 943, so we need a special/internal API/ctor to allow this
 200                         SocketAsyncEventArgs saea = new SocketAsyncEventArgs (true);
 201                         saea.RemoteEndPoint = new IPEndPoint (endpoint.Address, PolicyPort);
 202                         saea.Completed += delegate (object sender, SocketAsyncEventArgs e) {
 203                                 if (e.SocketError != SocketError.Success) {
 204                                         mre.Set ();
 205                                         return;
 206                                 }
 207
 208                                 switch (e.LastOperation) {
 209                                 case SocketAsyncOperation.Connect:
 210                                         e.SetBuffer (socket_policy_file_request, 0, socket_policy_file_request.Length);
 211                                         socket.SendAsync (e);
 212                                         break;
 213                                 case SocketAsyncOperation.Send:
 214                                         byte [] buffer = new byte [256];
 215                                         e.SetBuffer (buffer, 0, buffer.Length);
 216                                         socket.ReceiveAsync (e);
 217                                         break;
 218                                 case SocketAsyncOperation.Receive:
 219                                         int transfer = e.BytesTransferred;
 220                                         if (transfer > 0) {
 221                                                 ms.Write (e.Buffer, 0, transfer);
 222                                                 // Console.Write (Encoding.UTF8.GetString (e.Buffer, 0, transfer));
 223                                         }
 224
 225                                         if ((transfer == 0) || (transfer < e.Buffer.Length)) {
 226                                                 ms.Position = 0;
 227                                                 mre.Set ();
 228                                         } else {
 229                                                 socket.ReceiveAsync (e);
 230                                         }
 231                                         break;
 232                                 }
 233                         };
 234
 235                         socket.ConnectAsync (saea);
 236
 237                         // behave like there's no policy (no socket access) if we timeout
 238                         if (!mre.WaitOne (Timeout))
 239                                 return null;
 240
 241                         return ms;
 242                 }
 243
 244                 public static ClientAccessPolicy CreateForEndPoint (IPEndPoint endpoint)
 245                 {
 246                         Stream s = GetPolicyStream (endpoint);
 247                         if (s == null)
 248                                 return null;
 249
 250                         ClientAccessPolicy policy = null;
 251                         try {
 252                                 policy = (ClientAccessPolicy) ClientAccessPolicy.FromStream (s);
 253                         } catch (Exception ex) {
 254                                 Console.WriteLine (String.Format ("CrossDomainAccessManager caught an exception while reading {0}: {1}",
 255                                         endpoint, ex.Message));
 256                                 // and ignore.
 257                         }
 258
 259                         return policy;
 260                 }
 261
 262                 static public bool CheckEndPoint (EndPoint endpoint)
 263                 {
 264                         // if needed transform the DnsEndPoint into a usable IPEndPoint
 265                         IPEndPoint ip = (endpoint as IPEndPoint);
 266                         if (ip == null)
 267                                 throw new ArgumentException ("endpoint");
 268
 269                         // find the policy (cached or to be downloaded) associated with the endpoint
 270                         string address = ip.Address.ToString ();
 271                         ClientAccessPolicy policy = null;
 272                         if (!socket_policies.TryGetValue (address, out policy)) {
 273                                 policy = CreateForEndPoint (ip);
 274                                 socket_policies.Add (address, policy);
 275                         }
 276
 277                         // no access granted if no policy is available
 278                         if (policy == null)
 279                                 return false;
 280
 281                         // does the policy allows access ?
 282                         return policy.IsAllowed (ip);
 283                 }
 284 #endif
 285         }
 286 }
 287
 288 #endif
 289