mcs/class/corlib/System.Security.Cryptography/CryptoConfig.common.cs

   1 //
   2 // CryptoConfig.cs: Handles cryptographic implementations and OIDs mappings.
   3 //
   4 // Author:
   5 //      Sebastien Pouliot (sebastien@ximian.com)
   6 //      Tim Coleman (tim@timcoleman.com)
   7 //
   8 // (C) 2002, 2003 Motus Technologies Inc. (http://www.motus.com)
   9 // Copyright (C) Tim Coleman, 2004
  10 // Copyright (C) 2004-2007, 2009 Novell, Inc (http://www.novell.com)
  11 //
  12 // Permission is hereby granted, free of charge, to any person obtaining
  13 // a copy of this software and associated documentation files (the
  14 // "Software"), to deal in the Software without restriction, including
  15 // without limitation the rights to use, copy, modify, merge, publish,
  16 // distribute, sublicense, and/or sell copies of the Software, and to
  17 // permit persons to whom the Software is furnished to do so, subject to
  18 // the following conditions:
  19 //
  20 // The above copyright notice and this permission notice shall be
  21 // included in all copies or substantial portions of the Software.
  22 //
  23 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  24 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  25 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  26 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  27 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  28 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  29 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  30 //
  31
  32 using System.Collections.Generic;
  33
  34 namespace System.Security.Cryptography {
  35
  36         public partial class CryptoConfig
  37         {
  38                 static readonly object lockObject = new object ();
  39                 static Dictionary<string,Type> algorithms;
  40
  41                 public static void AddAlgorithm (Type algorithm, params string[] names)
  42                 {
  43                         if (algorithm == null)
  44                                 throw new ArgumentNullException (nameof (algorithm));
  45                         if (!algorithm.IsVisible)
  46                                 throw new ArgumentException ("Algorithms added to CryptoConfig must be accessable from outside their assembly.", nameof (algorithm));
  47                         if (names == null)
  48                                 throw new ArgumentNullException (nameof (names));
  49
  50                         var algorithmNames = new string [names.Length];
  51                         Array.Copy (names, algorithmNames, algorithmNames.Length);
  52
  53                         foreach (string name in algorithmNames) {
  54                                 if (string.IsNullOrEmpty (name)) {
  55                                         throw new ArgumentException ("CryptoConfig cannot add a mapping for a null or empty name.");
  56                                 }
  57                         }
  58
  59                         lock (lockObject) {
  60                                 if (algorithms == null) {
  61                                         Initialize ();
  62                                 }
  63
  64                                 foreach (string name in algorithmNames) {
  65                                         algorithms [name] = algorithm;
  66                                 }
  67                         }
  68                 }
  69
  70                 public static byte[] EncodeOID (string str)
  71                 {
  72                         if (str == null)
  73                                 throw new ArgumentNullException ("str");
  74                         char[] delim = { '.' };
  75                         string[] parts = str.Split (delim);
  76                         // according to X.208 n is always at least 2
  77                         if (parts.Length < 2) {
  78                                 throw new CryptographicUnexpectedOperationException (
  79                                         Locale.GetText ("OID must have at least two parts"));
  80                         }
  81
  82                         // we're sure that the encoded OID is shorter than its string representation
  83                         byte[] oid = new byte [str.Length];
  84                         // now encoding value
  85                         try {
  86                                 byte part0 = Convert.ToByte (parts [0]);
  87                                 // OID[0] > 2 is invalid but "supported" in MS BCL
  88                                 // uncomment next line to trap this error
  89                                 // if (part0 > 2) throw new CryptographicUnexpectedOperationException ();
  90                                 byte part1 = Convert.ToByte (parts [1]);
  91                                 // OID[1] >= 40 is illegal for OID[0] < 2 because of the % 40
  92                                 // however the syntax is "supported" in MS BCL
  93                                 // uncomment next 2 lines to trap this error
  94                                 //if ((part0 < 2) && (part1 >= 40))
  95                                 //      throw new CryptographicUnexpectedOperationException ();
  96                                 oid[2] = Convert.ToByte (part0 * 40 + part1);
  97                         }
  98                         catch {
  99                                 throw new CryptographicUnexpectedOperationException (
 100                                         Locale.GetText ("Invalid OID"));
 101                         }
 102                         int j = 3;
 103                         for (int i = 2; i < parts.Length; i++) {
 104                                 long x = Convert.ToInt64 (parts [i]);
 105                                 if (x > 0x7F) {
 106                                         byte[] num = EncodeLongNumber (x);
 107                                         Buffer.BlockCopy (num, 0, oid, j, num.Length);
 108                                         j += num.Length;
 109                                 }
 110                                 else
 111                                         oid[j++] = Convert.ToByte (x);
 112                         }
 113
 114                         int k = 2;
 115                         // copy the exact number of byte required
 116                         byte[] oid2 = new byte [j];
 117                         oid2[0] = 0x06; // always - this tag means OID
 118                         // Length (of value)
 119                         if (j > 0x7F) {
 120                                 // for compatibility with MS BCL
 121                                 throw new CryptographicUnexpectedOperationException (
 122                                         Locale.GetText ("OID > 127 bytes"));
 123                                 // comment exception and uncomment next 3 lines to remove restriction
 124                                 //byte[] num = EncodeLongNumber (j);
 125                                 //Buffer.BlockCopy (num, 0, oid, j, num.Length);
 126                                 //k = num.Length + 1;
 127                         }
 128                         else
 129                                 oid2 [1] = Convert.ToByte (j - 2);
 130
 131                         Buffer.BlockCopy (oid, k, oid2, k, j - k);
 132                         return oid2;
 133                 }
 134
 135                 // encode (7bits array) number greater than 127
 136                 private static byte[] EncodeLongNumber (long x)
 137                 {
 138                         // for MS BCL compatibility
 139                         // comment next two lines to remove restriction
 140                         if ((x > Int32.MaxValue) || (x < Int32.MinValue))
 141                                 throw new OverflowException (Locale.GetText ("Part of OID doesn't fit in Int32"));
 142
 143                         long y = x;
 144                         // number of bytes required to encode this number
 145                         int n = 1;
 146                         while (y > 0x7F) {
 147                                 y = y >> 7;
 148                                 n++;
 149                         }
 150                         byte[] num = new byte [n];
 151                         // encode all bytes
 152                         for (int i = 0; i < n; i++) {
 153                                 y = x >> (7 * i);
 154                                 y = y & 0x7F;
 155                                 if (i != 0)
 156                                         y += 0x80;
 157                                 num[n-i-1] = Convert.ToByte (y);
 158                         }
 159                         return num;
 160                 }
 161
 162                 [MonoLimitation ("nothing is FIPS certified so it never make sense to restrict to this (empty) subset")]
 163                 public static bool AllowOnlyFipsAlgorithms {
 164                         get { return false; }
 165                 }
 166         }
 167 }
 168