mcs/class/Mono.Security/Mono.Security.Protocol.Tls.Handshake.Client/TlsClientHello.cs

   1 // Transport Security Layer (TLS)
   2 // Copyright (c) 2003-2004 Carlos Guzman Alvarez
   3
   4 //
   5 // Permission is hereby granted, free of charge, to any person obtaining
   6 // a copy of this software and associated documentation files (the
   7 // "Software"), to deal in the Software without restriction, including
   8 // without limitation the rights to use, copy, modify, merge, publish,
   9 // distribute, sublicense, and/or sell copies of the Software, and to
  10 // permit persons to whom the Software is furnished to do so, subject to
  11 // the following conditions:
  12 //
  13 // The above copyright notice and this permission notice shall be
  14 // included in all copies or substantial portions of the Software.
  15 //
  16 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  17 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  18 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  19 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  20 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  21 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  22 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  23 //
  24
  25 using System;
  26 using System.Net;
  27 using System.Security.Cryptography;
  28
  29 namespace Mono.Security.Protocol.Tls.Handshake.Client
  30 {
  31         internal class TlsClientHello : HandshakeMessage
  32         {
  33                 #region Fields
  34
  35                 private byte[] random;
  36
  37                 #endregion
  38
  39                 #region Constructors
  40
  41                 public TlsClientHello(Context context)
  42                         : base(context, HandshakeType.ClientHello)
  43                 {
  44                 }
  45
  46                 #endregion
  47
  48                 #region Methods
  49
  50                 public override void Update()
  51                 {
  52                         ClientContext context = (ClientContext)this.Context;
  53
  54                         base.Update();
  55
  56                         context.ClientRandom            = random;
  57                         context.ClientHelloProtocol     = this.Context.Protocol;
  58
  59                         random = null;
  60                 }
  61
  62                 #endregion
  63
  64                 #region Protected Methods
  65
  66                 protected override void ProcessAsSsl3()
  67                 {
  68                         // Client Version
  69                         this.Write(this.Context.Protocol);
  70
  71                         // Random bytes - Unix time + Radom bytes [28]
  72                         TlsStream clientRandom = new TlsStream();
  73                         clientRandom.Write(this.Context.GetUnixTime());
  74                         clientRandom.Write(this.Context.GetSecureRandomBytes(28));
  75                         this.random = clientRandom.ToArray();
  76                         clientRandom.Reset();
  77
  78                         this.Write(this.random);
  79
  80                         // Session id
  81                         // Check if we have a cache session we could reuse
  82                         this.Context.SessionId = ClientSessionCache.FromHost (this.Context.ClientSettings.TargetHost);
  83                         if (this.Context.SessionId != null)
  84                         {
  85                                 this.Write((byte)this.Context.SessionId.Length);
  86                                 if (this.Context.SessionId.Length > 0)
  87                                 {
  88                                         this.Write(this.Context.SessionId);
  89                                 }
  90                         }
  91                         else
  92                         {
  93                                 this.Write((byte)0);
  94                         }
  95
  96                         // Write length of Cipher suites
  97                         this.Write((short)(this.Context.SupportedCiphers.Count*2));
  98
  99                         // Write Supported Cipher suites
 100                         for (int i = 0; i < this.Context.SupportedCiphers.Count; i++)
 101                         {
 102                                 this.Write((short)this.Context.SupportedCiphers[i].Code);
 103                         }
 104
 105                         // Compression methods length
 106                         this.Write((byte)1);
 107
 108                         // Compression methods ( 0 = none )
 109                         this.Write((byte)this.Context.CompressionMethod);
 110                 }
 111
 112                 protected override void ProcessAsTls1()
 113                 {
 114                         ProcessAsSsl3 ();
 115
 116                         // If applicable add the "server_name" extension to the hello message
 117                         // http://www.ietf.org/rfc/rfc3546.txt
 118                         string host = Context.ClientSettings.TargetHost;
 119                         // Our TargetHost might be an address (not a host *name*) - see bug #8553
 120                         // RFC3546 -> Literal IPv4 and IPv6 addresses are not permitted in "HostName".
 121                         IPAddress addr;
 122                         if (IPAddress.TryParse (host, out addr))
 123                                 return;
 124
 125                         TlsStream extensions = new TlsStream ();
 126                         byte[] server_name = System.Text.Encoding.UTF8.GetBytes (host);
 127                         extensions.Write ((short) 0x0000);                      // ExtensionType: server_name (0)
 128                         extensions.Write ((short) (server_name.Length + 5));    // ServerNameList (length)
 129                         extensions.Write ((short) (server_name.Length + 3));    // ServerName (length)
 130                         extensions.Write ((byte) 0x00);                         // NameType: host_name (0)
 131                         extensions.Write ((short) server_name.Length);          // HostName (length)
 132                         extensions.Write (server_name);                         // HostName (UTF8)
 133                         this.Write ((short) extensions.Length);
 134                         this.Write (extensions.ToArray ());
 135                 }
 136
 137                 #endregion
 138         }
 139 }