mcs/class/Mono.Security/Mono.Security.Protocol.Ntlm/Type2Message.cs

   1 //
   2 // Mono.Security.Protocol.Ntlm.Type2Message - Challenge
   3 //
   4 // Author:
   5 //      Sebastien Pouliot <sebastien@ximian.com>
   6 //
   7 // Copyright (C) 2003 Motus Technologies Inc. (http://www.motus.com)
   8 // Copyright (C) 2004 Novell, Inc (http://www.novell.com)
   9 //
  10 // References
  11 // a.   NTLM Authentication Scheme for HTTP, Ronald Tschalär
  12 //      http://www.innovation.ch/java/ntlm.html
  13 // b.   The NTLM Authentication Protocol, Copyright © 2003 Eric Glass
  14 //      http://davenport.sourceforge.net/ntlm.html
  15 //
  16 // Permission is hereby granted, free of charge, to any person obtaining
  17 // a copy of this software and associated documentation files (the
  18 // "Software"), to deal in the Software without restriction, including
  19 // without limitation the rights to use, copy, modify, merge, publish,
  20 // distribute, sublicense, and/or sell copies of the Software, and to
  21 // permit persons to whom the Software is furnished to do so, subject to
  22 // the following conditions:
  23 //
  24 // The above copyright notice and this permission notice shall be
  25 // included in all copies or substantial portions of the Software.
  26 //
  27 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  28 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  29 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  30 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  31 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  32 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  33 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  34 //
  35
  36 using System;
  37 using System.Text;
  38 using System.Security.Cryptography;
  39
  40 namespace Mono.Security.Protocol.Ntlm {
  41
  42 #if INSIDE_SYSTEM
  43         internal
  44 #else
  45         public
  46 #endif
  47         class Type2Message : MessageBase {
  48
  49                 private byte[] _nonce;
  50                 private string _targetName;
  51                 private byte[] _targetInfo;
  52
  53                 public Type2Message () : base (2)
  54                 {
  55                         _nonce = new byte [8];
  56                         RandomNumberGenerator rng = RandomNumberGenerator.Create ();
  57                         rng.GetBytes (_nonce);
  58                         // default values
  59                         Flags = (NtlmFlags) 0x8201;
  60                 }
  61
  62                 public Type2Message (byte[] message) : base (2)
  63                 {
  64                         _nonce = new byte [8];
  65                         Decode (message);
  66                 }
  67
  68                 ~Type2Message ()
  69                 {
  70                         if (_nonce != null)
  71                                 Array.Clear (_nonce, 0, _nonce.Length);
  72                 }
  73
  74                 // properties
  75
  76                 public byte[] Nonce {
  77                         get { return (byte[]) _nonce.Clone (); }
  78                         set {
  79                                 if (value == null)
  80                                         throw new ArgumentNullException ("Nonce");
  81                                 if (value.Length != 8) {
  82                                         string msg = Locale.GetText ("Invalid Nonce Length (should be 8 bytes).");
  83                                         throw new ArgumentException (msg, "Nonce");
  84                                 }
  85                                 _nonce = (byte[]) value.Clone ();
  86                         }
  87                 }
  88
  89                 public string TargetName {
  90                         get { return _targetName; }
  91                 }
  92
  93                 public byte[] TargetInfo {
  94                         get { return (byte[])_targetInfo.Clone (); }
  95                 }
  96
  97                 // methods
  98
  99                 protected override void Decode (byte[] message)
 100                 {
 101                         base.Decode (message);
 102
 103                         Flags = (NtlmFlags)BitConverterLE.ToUInt32 (message, 20);
 104
 105                         Buffer.BlockCopy (message, 24, _nonce, 0, 8);
 106
 107                         var tname_len = BitConverterLE.ToUInt16 (message, 12);
 108                         var tname_off = BitConverterLE.ToUInt16 (message, 16);
 109                         if (tname_len > 0) {
 110                                 if ((Flags & NtlmFlags.NegotiateOem) != 0)
 111                                         _targetName = Encoding.ASCII.GetString (message, tname_off, tname_len);
 112                                 else
 113                                         _targetName = Encoding.Unicode.GetString (message, tname_off, tname_len);
 114                         }
 115
 116                         // The Target Info block is optional.
 117                         if (message.Length >= 48) {
 118                                 var tinfo_len = BitConverterLE.ToUInt16 (message, 40);
 119                                 var tinfo_off = BitConverterLE.ToUInt16 (message, 44);
 120                                 if (tinfo_len > 0) {
 121                                         _targetInfo = new byte [tinfo_len];
 122                                         Buffer.BlockCopy (message, tinfo_off, _targetInfo, 0, tinfo_len);
 123                                 }
 124                         }
 125                 }
 126
 127                 public override byte[] GetBytes ()
 128                 {
 129                         byte[] data = PrepareMessage (40);
 130
 131                         // message length
 132                         short msg_len = (short)data.Length;
 133                         data [16] = (byte) msg_len;
 134                         data [17] = (byte)(msg_len >> 8);
 135
 136                         // flags
 137                         data [20] = (byte) Flags;
 138                         data [21] = (byte)((uint)Flags >> 8);
 139                         data [22] = (byte)((uint)Flags >> 16);
 140                         data [23] = (byte)((uint)Flags >> 24);
 141
 142                         Buffer.BlockCopy (_nonce, 0, data, 24, _nonce.Length);
 143                         return data;
 144                 }
 145         }
 146 }