// Sebastien Pouliot <sebastien@ximian.com>
//
// Portions (C) 2002 Motus Technologies Inc. (http://www.motus.com)
-// (C) 2004 Novell (http://www.novell.com)
+// Copyright (C) 2004-2005 Novell, Inc (http://www.novell.com)
+//
+// Permission is hereby granted, free of charge, to any person obtaining
+// a copy of this software and associated documentation files (the
+// "Software"), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to
+// permit persons to whom the Software is furnished to do so, subject to
+// the following conditions:
+//
+// The above copyright notice and this permission notice shall be
+// included in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//
-using System;
using System.Globalization;
-using System.Security.Cryptography;
// References:
// a. FIPS PUB 46-3: Data Encryption Standard
public abstract class DES : SymmetricAlgorithm {
- const int blockSizeByte = 8;
+ private const int keySizeByte = 8;
public DES ()
{
KeySizeValue = 64;
BlockSizeValue = 64;
- FeedbackSizeValue = 64;
+ FeedbackSizeValue = 8;
LegalKeySizesValue = new KeySizes[1];
LegalKeySizesValue[0] = new KeySizes(64, 64, 0);
return (DES) CryptoConfig.CreateFromName (algo);
}
- internal static ulong PackKey (byte[] key)
- {
- byte[] paritySetKey = new byte [blockSizeByte];
- // adapted from bouncycastle - see bouncycastle.txt
- for (int i=0; i < key.Length; i++) {
- byte b = key [i];
- paritySetKey [i] = (byte)((b & 0xfe) |
- ((((b >> 1) ^ (b >> 2) ^ (b >> 3) ^ (b >> 4) ^
- (b >> 5) ^ (b >> 6) ^ (b >> 7)) ^ 0x01) & 0x01));
- }
-
- ulong res = 0;
- for (int i = 0, sh = 8*blockSizeByte; (sh = sh - 8) >= 0; i++) {
- res |= (ulong) paritySetKey [i] << sh;
- }
-
- Array.Clear (paritySetKey, 0, paritySetKey.Length);
- return res;
- }
// Ek(Ek(m)) = m
- internal static readonly ulong[] weakKeys = {
- 0x0101010101010101, /* 0000000 0000000 */
- 0xFEFEFEFEFEFEFEFE, /* FFFFFFF FFFFFFF */
- 0x1F1F1F1F0E0E0E0E, /* 0000000 FFFFFFF */
- 0xE0E0E0E0F1F1F1F1 /* FFFFFFF 0000000 */
+ internal static readonly byte[,] weakKeys = {
+ { 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01 },
+ { 0x1F, 0x1F, 0x1F, 0x1F, 0x0F, 0x0F, 0x0F, 0x0F },
+ { 0xE1, 0xE1, 0xE1, 0xE1, 0xF1, 0xF1, 0xF1, 0xF1 },
+ { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF },
};
// Ek1(Ek2(m)) = m
- internal static readonly ulong[] semiweakKeys = {
- 0x01FE01FE01FE01FE, 0xFE01FE01FE01FE01,
- 0x1FE01FE00EF10EF1, 0xE01FE01FF10EF10E,
- 0x01E001E001F101F1, 0xE001E001F101F101,
- 0x1FFE1FFE0EFE0EFE, 0xFE1FFE1FFE0EFE0E,
- 0x011F011F010E010E, 0x1F011F010E010E01,
- 0xE0FEE0FEF1FEF1FE, 0xFEE0FEE0FEF1FEF1
- };
+ internal static readonly byte[,] semiWeakKeys = {
+ { 0x00, 0x1E, 0x00, 0x1E, 0x00, 0x0E, 0x00, 0x0E }, // map to packed key 011F011F010E010E\r
+ { 0x00, 0xE0, 0x00, 0xE0, 0x00, 0xF0, 0x00, 0xF0 }, // map to packed key 01E001E001F101F1\r
+ { 0x00, 0xFE, 0x00, 0xFE, 0x00, 0xFE, 0x00, 0xFE }, // map to packed key 01FE01FE01FE01FE\r
+ { 0x1E, 0x00, 0x1E, 0x00, 0x0E, 0x00, 0x0E, 0x00 }, // map to packed key 1F011F010E010E01\r
+ { 0x1E, 0xE0, 0x1E, 0xE0, 0x0E, 0xF0, 0x0E, 0xF0 }, // map to packed key 1FE01FE00EF10EF1\r
+ { 0x1E, 0xFE, 0x1E, 0xFE, 0x0E, 0xFE, 0x0E, 0xFE }, // map to packed key 1FFE1FFE0EFE0EFE\r
+ { 0xE0, 0x00, 0xE0, 0x00, 0xF0, 0x00, 0xF0, 0x00 }, // map to packed key E001E001F101F101\r
+ { 0xE0, 0x1E, 0xE0, 0x1E, 0xF0, 0x0E, 0xF0, 0x0E }, // map to packed key E01FE01FF10EF10E\r
+ { 0xE0, 0xFE, 0xE0, 0xFE, 0xF0, 0xFE, 0xF0, 0xFE }, // map to packed key E0FEE0FEF1FEF1FE\r
+ { 0xFE, 0x00, 0xFE, 0x00, 0xFE, 0x00, 0xFE, 0x00 }, // map to packed key FE01FE01FE01FE01\r
+ { 0xFE, 0x1E, 0xFE, 0x1E, 0xFE, 0x0E, 0xFE, 0x0E }, // map to packed key FE1FFE1FFE0EFE0E\r
+ { 0xFE, 0xE0, 0xFE, 0xE0, 0xFE, 0xF0, 0xFE, 0xF0 }, // map to packed key FEE0FEE0FEF1FEF1\r
+ };\r
public static bool IsWeakKey (byte[] rgbKey)
{
- if (rgbKey.Length != blockSizeByte)
+ if (rgbKey.Length != keySizeByte)
throw new CryptographicException (Locale.GetText ("Wrong Key Length"));
- ulong lk = PackKey (rgbKey);
- foreach (ulong wk in weakKeys) {
- if (lk == wk)
+ // (fast) pre-check with "weak bytes"
+ for (int i=0; i < rgbKey.Length; i++) {
+ switch (rgbKey [i] | 0x11) {
+ case 0x11:
+ case 0x1F:
+ case 0xF1:
+ case 0xFF:
+ break;
+ default:
+ return false;
+ }
+ }
+
+ // compare with known weak keys
+ for (int i=0; i < (weakKeys.Length >> 3); i++) {
+ int j = 0;
+ for (; j < rgbKey.Length; j++) {
+ if ((rgbKey [j] ^ weakKeys [i,j]) > 1)
+ break;
+ }
+ if (j==8)
return true;
}
return false;
public static bool IsSemiWeakKey (byte[] rgbKey)
{
- if (rgbKey.Length != blockSizeByte)
+ if (rgbKey.Length != keySizeByte)
throw new CryptographicException (Locale.GetText ("Wrong Key Length"));
- ulong lk = PackKey (rgbKey);
- foreach (ulong swk in semiweakKeys) {
- if (lk == swk)
+ // (fast) pre-check with "weak bytes"
+ for (int i=0; i < rgbKey.Length; i++) {
+ switch (rgbKey [i] | 0x11) {
+ case 0x11:
+ case 0x1F:
+ case 0xF1:
+ case 0xFF:
+ break;
+ default:
+ return false;
+ }
+ }
+
+ // compare with known weak keys
+ for (int i=0; i < (semiWeakKeys.Length >> 3); i++) {
+ int j = 0;
+ for (; j < rgbKey.Length; j++) {
+ if ((rgbKey [j] ^ semiWeakKeys [i,j]) > 1)
+ break;
+ }
+ if (j==8)
return true;
}
return false;
set {
if (value == null)
throw new ArgumentNullException ("Key");
- if (value.Length != blockSizeByte)
+ if (value.Length != keySizeByte)
throw new ArgumentException (Locale.GetText ("Wrong Key Length"));
if (IsWeakKey (value))
throw new CryptographicException (Locale.GetText ("Weak Key"));
projects / mono.git / blobdiff