mcs/class/Mono.Security/Mono.Security.Protocol.Ntlm/Type3Message.cs

   1 //
   2 // Mono.Security.Protocol.Ntlm.Type3Message - Authentication
   3 //
   4 // Author:
   5 //      Sebastien Pouliot <sebastien@ximian.com>
   6 //
   7 // (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.Globalization;
  38 using System.Text;
  39
  40 namespace Mono.Security.Protocol.Ntlm {
  41
  42 #if INSIDE_SYSTEM
  43         internal
  44 #else
  45         public
  46 #endif
  47         class Type3Message : MessageBase {
  48
  49                 private NtlmAuthLevel _level;
  50                 private byte[] _challenge;
  51                 private string _host;
  52                 private string _domain;
  53                 private string _username;
  54                 private string _password;
  55                 private Type2Message _type2;
  56                 private byte[] _lm;
  57                 private byte[] _nt;
  58
  59                 internal const string LegacyAPIWarning =
  60                         "Use of this API is highly discouraged, " +
  61                         "it selects legacy-mode LM/NTLM authentication, which sends " +
  62                         "your password in very weak encryption over the wire even if " +
  63                         "the server supports the more secure NTLMv2 / NTLMv2 Session. " +
  64                         "You need to use the new `Type3Message (Type2Message)' constructor " +
  65                         "to use the more secure NTLMv2 / NTLMv2 Session authentication modes. " +
  66                         "These require the Type 2 message from the server to compute the response.";
  67
  68                 [Obsolete (LegacyAPIWarning)]
  69                 public Type3Message () : base (3)
  70                 {
  71                         if (DefaultAuthLevel != NtlmAuthLevel.LM_and_NTLM)
  72                                 throw new InvalidOperationException (
  73                                         "Refusing to use legacy-mode LM/NTLM authentication " +
  74                                         "unless explicitly enabled using DefaultAuthLevel.");
  75
  76                         // default values
  77                         _domain = Environment.UserDomainName;
  78                         _host = Environment.MachineName;
  79                         _username = Environment.UserName;
  80                         _level = NtlmAuthLevel.LM_and_NTLM;
  81                         Flags = (NtlmFlags) 0x8201;
  82                 }
  83
  84                 public Type3Message (byte[] message) : base (3)
  85                 {
  86                         Decode (message);
  87                 }
  88
  89                 public Type3Message (Type2Message type2) : base (3)
  90                 {
  91                         _type2 = type2;
  92                         _level = DefaultAuthLevel;
  93                         _challenge = (byte[]) type2.Nonce.Clone ();
  94
  95                         _domain = type2.TargetName;
  96                         _host = Environment.MachineName;
  97                         _username = Environment.UserName;
  98
  99                         Flags = (NtlmFlags) 0x8200;
 100                         if ((type2.Flags & NtlmFlags.NegotiateUnicode) != 0)
 101                                 Flags |= NtlmFlags.NegotiateUnicode;
 102                         else
 103                                 Flags |= NtlmFlags.NegotiateOem;
 104
 105                         if ((type2.Flags & NtlmFlags.NegotiateNtlm2Key) != 0)
 106                                 Flags |= NtlmFlags.NegotiateNtlm2Key;
 107                 }
 108
 109                 ~Type3Message ()
 110                 {
 111                         if (_challenge != null)
 112                                 Array.Clear (_challenge, 0, _challenge.Length);
 113                         if (_lm != null)
 114                                 Array.Clear (_lm, 0, _lm.Length);
 115                         if (_nt != null)
 116                                 Array.Clear (_nt, 0, _nt.Length);
 117                 }
 118
 119                 // Default auth level
 120
 121                 static NtlmAuthLevel _default = NtlmAuthLevel.LM_and_NTLM_and_try_NTLMv2_Session;
 122
 123                 public static NtlmAuthLevel DefaultAuthLevel {
 124                         get { return _default; }
 125                         set { _default = value; }
 126                 }
 127
 128                 public NtlmAuthLevel Level {
 129                         get { return _level; }
 130                         set { _level = value; }
 131                 }
 132
 133                 // properties
 134
 135                 [Obsolete (LegacyAPIWarning)]
 136                 public byte[] Challenge {
 137                         get {
 138                                 if (_challenge == null)
 139                                         return null;
 140                                 return (byte[]) _challenge.Clone (); }
 141                         set {
 142                                 if ((_type2 != null) || (_level != NtlmAuthLevel.LM_and_NTLM))
 143                                         throw new InvalidOperationException (
 144                                                 "Refusing to use legacy-mode LM/NTLM authentication " +
 145                                                         "unless explicitly enabled using DefaultAuthLevel.");
 146
 147                                 if (value == null)
 148                                         throw new ArgumentNullException ("Challenge");
 149                                 if (value.Length != 8) {
 150                                         string msg = Locale.GetText ("Invalid Challenge Length (should be 8 bytes).");
 151                                         throw new ArgumentException (msg, "Challenge");
 152                                 }
 153                                 _challenge = (byte[]) value.Clone ();
 154                         }
 155                 }
 156
 157                 public string Domain {
 158                         get { return _domain; }
 159                         set {
 160                                 if (value == null)
 161                                         value = "";
 162                                 if (value == "")
 163                                         Flags &= ~NtlmFlags.NegotiateDomainSupplied;
 164                                 else
 165                                         Flags |= NtlmFlags.NegotiateDomainSupplied;
 166
 167                                 _domain = value;
 168                         }
 169                 }
 170
 171                 public string Host {
 172                         get { return _host; }
 173                         set {
 174                                 if (value == null)
 175                                         value = "";
 176                                 if (value == "")
 177                                         Flags &= ~NtlmFlags.NegotiateWorkstationSupplied;
 178                                 else
 179                                         Flags |= NtlmFlags.NegotiateWorkstationSupplied;
 180
 181                                 _host = value;
 182                         }
 183                 }
 184
 185                 public string Password {
 186                         get { return _password; }
 187                         set { _password = value; }
 188                 }
 189
 190                 public string Username {
 191                         get { return _username; }
 192                         set { _username = value; }
 193                 }
 194
 195                 public byte[] LM {
 196                         get { return _lm; }
 197                 }
 198
 199                 public byte[] NT {
 200                         get { return _nt; }
 201                         set { _nt = value; }
 202                 }
 203
 204                 // methods
 205
 206                 protected override void Decode (byte[] message)
 207                 {
 208                         base.Decode (message);
 209
 210                         _password = null;
 211
 212                         if (message.Length >= 64)
 213                                 Flags = (NtlmFlags)BitConverterLE.ToUInt32 (message, 60);
 214                         else
 215                                 Flags = (NtlmFlags)0x8201;
 216
 217                         int lm_len = BitConverterLE.ToUInt16 (message, 12);
 218                         int lm_off = BitConverterLE.ToUInt16 (message, 16);
 219                         _lm = new byte [lm_len];
 220                         Buffer.BlockCopy (message, lm_off, _lm, 0, lm_len);
 221
 222                         int nt_len = BitConverterLE.ToUInt16 (message, 20);
 223                         int nt_off = BitConverterLE.ToUInt16 (message, 24);
 224                         _nt = new byte [nt_len];
 225                         Buffer.BlockCopy (message, nt_off, _nt, 0, nt_len);
 226
 227                         int dom_len = BitConverterLE.ToUInt16 (message, 28);
 228                         int dom_off = BitConverterLE.ToUInt16 (message, 32);
 229                         _domain = DecodeString (message, dom_off, dom_len);
 230
 231                         int user_len = BitConverterLE.ToUInt16 (message, 36);
 232                         int user_off = BitConverterLE.ToUInt16 (message, 40);
 233                         _username = DecodeString (message, user_off, user_len);
 234
 235                         int host_len = BitConverterLE.ToUInt16 (message, 44);
 236                         int host_off = BitConverterLE.ToUInt16 (message, 48);
 237                         _host = DecodeString (message, host_off, host_len);
 238
 239                         // Session key.  We don't use it yet.
 240                         // int skey_len = BitConverterLE.ToUInt16 (message, 52);
 241                         // int skey_off = BitConverterLE.ToUInt16 (message, 56);
 242                 }
 243
 244                 string DecodeString (byte[] buffer, int offset, int len)
 245                 {
 246                         if ((Flags & NtlmFlags.NegotiateUnicode) != 0)
 247                                 return Encoding.Unicode.GetString (buffer, offset, len);
 248                         else
 249                                 return Encoding.ASCII.GetString (buffer, offset, len);
 250                 }
 251
 252                 byte[] EncodeString (string text)
 253                 {
 254                         if (text == null)
 255                                 return new byte [0];
 256                         if ((Flags & NtlmFlags.NegotiateUnicode) != 0)
 257                                 return Encoding.Unicode.GetBytes (text);
 258                         else
 259                                 return Encoding.ASCII.GetBytes (text);
 260                 }
 261
 262                 public override byte[] GetBytes ()
 263                 {
 264                         byte[] target = EncodeString (_domain);
 265                         byte[] user = EncodeString (_username);
 266                         byte[] host = EncodeString (_host);
 267
 268                         byte[] lm, ntlm;
 269                         if (_type2 == null) {
 270                                 if (_level != NtlmAuthLevel.LM_and_NTLM)
 271                                         throw new InvalidOperationException (
 272                                                 "Refusing to use legacy-mode LM/NTLM authentication " +
 273                                                         "unless explicitly enabled using DefaultAuthLevel.");
 274
 275                                 using (var legacy = new ChallengeResponse (_password, _challenge)) {
 276                                         lm = legacy.LM;
 277                                         ntlm = legacy.NT;
 278                                 }
 279                         } else {
 280                                 ChallengeResponse2.Compute (_type2, _level, _username, _password, _domain, out lm, out ntlm);
 281                         }
 282
 283                         var lmresp_len = lm != null ? lm.Length : 0;
 284                         var ntresp_len = ntlm != null ? ntlm.Length : 0;
 285
 286                         byte[] data = PrepareMessage (64 + target.Length + user.Length + host.Length + lmresp_len + ntresp_len);
 287
 288                         // LM response
 289                         short lmresp_off = (short)(64 + target.Length + user.Length + host.Length);
 290                         data [12] = (byte)lmresp_len;
 291                         data [13] = (byte)0x00;
 292                         data [14] = (byte)lmresp_len;
 293                         data [15] = (byte)0x00;
 294                         data [16] = (byte)lmresp_off;
 295                         data [17] = (byte)(lmresp_off >> 8);
 296
 297                         // NT response
 298                         short ntresp_off = (short)(lmresp_off + lmresp_len);
 299                         data [20] = (byte)ntresp_len;
 300                         data [21] = (byte)(ntresp_len >> 8);
 301                         data [22] = (byte)ntresp_len;
 302                         data [23] = (byte)(ntresp_len >> 8);
 303                         data [24] = (byte)ntresp_off;
 304                         data [25] = (byte)(ntresp_off >> 8);
 305
 306                         // target
 307                         short dom_len = (short)target.Length;
 308                         short dom_off = 64;
 309                         data [28] = (byte)dom_len;
 310                         data [29] = (byte)(dom_len >> 8);
 311                         data [30] = data [28];
 312                         data [31] = data [29];
 313                         data [32] = (byte)dom_off;
 314                         data [33] = (byte)(dom_off >> 8);
 315
 316                         // username
 317                         short uname_len = (short)user.Length;
 318                         short uname_off = (short)(dom_off + dom_len);
 319                         data [36] = (byte)uname_len;
 320                         data [37] = (byte)(uname_len >> 8);
 321                         data [38] = data [36];
 322                         data [39] = data [37];
 323                         data [40] = (byte)uname_off;
 324                         data [41] = (byte)(uname_off >> 8);
 325
 326                         // host
 327                         short host_len = (short)host.Length;
 328                         short host_off = (short)(uname_off + uname_len);
 329                         data [44] = (byte)host_len;
 330                         data [45] = (byte)(host_len >> 8);
 331                         data [46] = data [44];
 332                         data [47] = data [45];
 333                         data [48] = (byte)host_off;
 334                         data [49] = (byte)(host_off >> 8);
 335
 336                         // message length
 337                         short msg_len = (short)data.Length;
 338                         data [56] = (byte)msg_len;
 339                         data [57] = (byte)(msg_len >> 8);
 340
 341                         int flags = (int)Flags;
 342
 343                         // options flags
 344                         data [60] = (byte)flags;
 345                         data [61] = (byte)((uint)flags >> 8);
 346                         data [62] = (byte)((uint)flags >> 16);
 347                         data [63] = (byte)((uint)flags >> 24);
 348
 349                         Buffer.BlockCopy (target, 0, data, dom_off, target.Length);
 350                         Buffer.BlockCopy (user, 0, data, uname_off, user.Length);
 351                         Buffer.BlockCopy (host, 0, data, host_off, host.Length);
 352
 353                         if (lm != null) {
 354                                 Buffer.BlockCopy (lm, 0, data, lmresp_off, lm.Length);
 355                                 Array.Clear (lm, 0, lm.Length);
 356                         }
 357                         Buffer.BlockCopy (ntlm, 0, data, ntresp_off, ntlm.Length);
 358                         Array.Clear (ntlm, 0, ntlm.Length);
 359
 360                         return data;
 361                 }
 362         }
 363 }