mcs/class/Mono.Security/Mono.Security.Protocol.Tls/Alert.cs

   1
   2 //
   3 // Permission is hereby granted, free of charge, to any person obtaining
   4 // a copy of this software and associated documentation files (the
   5 // "Software"), to deal in the Software without restriction, including
   6 // without limitation the rights to use, copy, modify, merge, publish,
   7 // distribute, sublicense, and/or sell copies of the Software, and to
   8 // permit persons to whom the Software is furnished to do so, subject to
   9 // the following conditions:
  10 //
  11 // The above copyright notice and this permission notice shall be
  12 // included in all copies or substantial portions of the Software.
  13 //
  14 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  15 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  16 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  17 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  18 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  19 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  20 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  21 //
  22 /* Transport Security Layer (TLS)
  23  * Copyright (c) 2003-2004 Carlos Guzman Alvarez
  24  *
  25  * Permission is hereby granted, free of charge, to any person
  26  * obtaining a copy of this software and associated documentation
  27  * files (the "Software"), to deal in the Software without restriction,
  28  * including without limitation the rights to use, copy, modify, merge,
  29  * publish, distribute, sublicense, and/or sell copies of the Software,
  30  * and to permit persons to whom the Software is furnished to do so,
  31  * subject to the following conditions:
  32  *
  33  * The above copyright notice and this permission notice shall be included
  34  * in all copies or substantial portions of the Software.
  35  *
  36  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  37  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
  38  * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  39  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
  40  * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
  41  * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  42  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  43  * DEALINGS IN THE SOFTWARE.
  44  */
  45
  46 using System;
  47 using Mono.Security.Protocol.Tls;
  48
  49 namespace Mono.Security.Protocol.Tls
  50 {
  51         #region Enumerations
  52
  53         [Serializable]
  54         internal enum AlertLevel : byte
  55         {
  56                 Warning = 1,
  57                 Fatal   = 2
  58         }
  59
  60         [Serializable]
  61         internal enum AlertDescription : byte
  62         {
  63                 CloseNotify                             = 0,
  64                 UnexpectedMessage               = 10,
  65                 BadRecordMAC                    = 20,
  66                 DecryptionFailed                = 21,
  67                 RecordOverflow                  = 22,
  68                 DecompressionFailiure   = 30,
  69                 HandshakeFailiure               = 40,
  70                 BadCertificate                  = 42,
  71                 UnsupportedCertificate  = 43,
  72                 CertificateRevoked              = 44,
  73                 CertificateExpired              = 45,
  74                 CertificateUnknown              = 46,
  75                 IlegalParameter                 = 47,
  76                 UnknownCA                               = 48,
  77                 AccessDenied                    = 49,
  78                 DecodeError                             = 50,
  79                 DecryptError                    = 51,
  80                 ExportRestriction               = 60,
  81                 ProtocolVersion                 = 70,
  82                 InsuficientSecurity             = 71,
  83                 InternalError                   = 80,
  84                 UserCancelled                   = 90,
  85                 NoRenegotiation                 = 100
  86         }
  87
  88         #endregion
  89
  90         internal class Alert
  91         {
  92                 #region Fields
  93
  94                 private AlertLevel                      level;
  95                 private AlertDescription        description;
  96
  97                 #endregion
  98
  99                 #region Properties
 100
 101                 public AlertLevel Level
 102                 {
 103                         get { return this.level; }
 104                 }
 105
 106                 public AlertDescription Description
 107                 {
 108                         get { return this.description; }
 109                 }
 110
 111                 public string Message
 112                 {
 113                         get { return Alert.GetAlertMessage(this.description); }
 114                 }
 115
 116                 public bool IsWarning
 117                 {
 118                         get { return this.level == AlertLevel.Warning ? true : false; }
 119                 }
 120
 121                 /*
 122                 public bool IsFatal
 123                 {
 124                         get { return this.level == AlertLevel.Fatal ? true : false; }
 125                 }
 126                 */
 127
 128                 public bool IsCloseNotify
 129                 {
 130                         get
 131                         {
 132                                 if (this.IsWarning &&
 133                                         this.description == AlertDescription.CloseNotify)
 134                                 {
 135                                         return true;
 136                                 }
 137
 138                                 return false;
 139                         }
 140                 }
 141
 142                 #endregion
 143
 144                 #region Constructors
 145
 146                 public Alert(AlertDescription description)
 147                 {
 148                         this.inferAlertLevel();
 149                         this.description = description;
 150                 }
 151
 152                 public Alert(
 153                         AlertLevel                      level,
 154                         AlertDescription        description)
 155                 {
 156                         this.level                      = level;
 157                         this.description        = description;
 158                 }
 159
 160                 #endregion
 161
 162                 #region Private Methods
 163
 164                 private void inferAlertLevel()
 165                 {
 166                         switch (description)
 167                         {
 168                                 case AlertDescription.CloseNotify:
 169                                 case AlertDescription.NoRenegotiation:
 170                                 case AlertDescription.UserCancelled:
 171                                         this.level = AlertLevel.Warning;
 172                                         break;
 173
 174                                 case AlertDescription.AccessDenied:
 175                                 case AlertDescription.BadCertificate:
 176                                 case AlertDescription.BadRecordMAC:
 177                                 case AlertDescription.CertificateExpired:
 178                                 case AlertDescription.CertificateRevoked:
 179                                 case AlertDescription.CertificateUnknown:
 180                                 case AlertDescription.DecodeError:
 181                                 case AlertDescription.DecompressionFailiure:
 182                                 case AlertDescription.DecryptError:
 183                                 case AlertDescription.DecryptionFailed:
 184                                 case AlertDescription.ExportRestriction:
 185                                 case AlertDescription.HandshakeFailiure:
 186                                 case AlertDescription.IlegalParameter:
 187                                 case AlertDescription.InsuficientSecurity:
 188                                 case AlertDescription.InternalError:
 189                                 case AlertDescription.ProtocolVersion:
 190                                 case AlertDescription.RecordOverflow:
 191                                 case AlertDescription.UnexpectedMessage:
 192                                 case AlertDescription.UnknownCA:
 193                                 case AlertDescription.UnsupportedCertificate:
 194                                 default:
 195                                         this.level = AlertLevel.Fatal;
 196                                         break;
 197                         }
 198                 }
 199
 200                 #endregion
 201
 202                 #region Static Methods
 203
 204                 public static string GetAlertMessage(AlertDescription description)
 205                 {
 206                         #if (DEBUG)
 207                         switch (description)
 208                         {
 209                                 case AlertDescription.AccessDenied:
 210                                         return "An inappropriate message was received.";
 211
 212                                 case AlertDescription.BadCertificate:
 213                                         return "TLSCiphertext decrypted in an invalid way.";
 214
 215                                 case AlertDescription.BadRecordMAC:
 216                                         return "Record with an incorrect MAC.";
 217
 218                                 case AlertDescription.CertificateExpired:
 219                                         return "Certificate has expired or is not currently valid";
 220
 221                                 case AlertDescription.CertificateRevoked:
 222                                         return "Certificate was revoked by its signer.";
 223
 224                                 case AlertDescription.CertificateUnknown:
 225                                         return "Certificate Unknown.";
 226
 227                                 case AlertDescription.CloseNotify:
 228                                         return "Connection closed";
 229
 230                                 case AlertDescription.DecodeError:
 231                                         return "A message could not be decoded because some field was out of the specified range or the length of the message was incorrect.";
 232
 233                                 case AlertDescription.DecompressionFailiure:
 234                                         return "The decompression function received improper input (e.g. data that would expand to excessive length).";
 235
 236                                 case AlertDescription.DecryptError:
 237                                         return "TLSCiphertext decrypted in an invalid way: either it wasn`t an even multiple of the block length or its padding values, when checked, weren`t correct.";
 238
 239                                 case AlertDescription.DecryptionFailed:
 240                                         return "Handshake cryptographic operation failed, including being unable to correctly verify a signature, decrypt a key exchange, or validate finished message.";
 241
 242                                 case AlertDescription.ExportRestriction:
 243                                         return "Negotiation not in compliance with export restrictions was detected.";
 244
 245                                 case AlertDescription.HandshakeFailiure:
 246                                         return "Unable to negotiate an acceptable set of security parameters given the options available.";
 247
 248                                 case AlertDescription.IlegalParameter:
 249                                         return "A field in the handshake was out of range or inconsistent with other fields.";
 250
 251                                 case AlertDescription.InsuficientSecurity:
 252                                         return "Negotiation has failed specifically because the server requires ciphers more secure than those supported by the client.";
 253
 254                                 case AlertDescription.InternalError:
 255                                         return "Internal error unrelated to the peer or the correctness of the protocol makes it impossible to continue.";
 256
 257                                 case AlertDescription.NoRenegotiation:
 258                                         return "Invalid renegotiation.";
 259
 260                                 case AlertDescription.ProtocolVersion:
 261                                         return "Unsupported protocol version.";
 262
 263                                 case AlertDescription.RecordOverflow:
 264                                         return "Invalid length on TLSCiphertext record or TLSCompressed record.";
 265
 266                                 case AlertDescription.UnexpectedMessage:
 267                                         return "Invalid message received.";
 268
 269                                 case AlertDescription.UnknownCA:
 270                                         return "CA can't be identified as a trusted CA.";
 271
 272                                 case AlertDescription.UnsupportedCertificate:
 273                                         return "Certificate was of an unsupported type.";
 274
 275                                 case AlertDescription.UserCancelled:
 276                                         return "Handshake cancelled by user.";
 277
 278                                 default:
 279                                         return "";
 280                         }
 281                         #else
 282                         return "The authentication or decryption has failed.";
 283                         #endif
 284                 }
 285
 286                 #endregion
 287         }
 288 }