| public static IsWeakKey ( byte rgbKey ) : bool | ||
| rgbKey | byte | |
| return | bool | |
public override ICryptoTransform CreateDecryptor(byte[] rgbKey, byte[] rgbIV)
{
if (TripleDES.IsWeakKey(rgbKey))
{
throw new CryptographicException(Environment.GetResourceString("Cryptography_InvalidKey_Weak"), "TripleDES");
}
return(this._NewEncryptor(rgbKey, this.ModeValue, rgbIV, this.FeedbackSizeValue, CryptoAPITransformMode.Decrypt));
}
/// <summary>Generates a random <see cref="P:System.Security.Cryptography.SymmetricAlgorithm.Key" /> to be used for the algorithm.</summary>
// Token: 0x060023D2 RID: 9170 RVA: 0x00082688 File Offset: 0x00080888
public override void GenerateKey()
{
this.KeyValue = new byte[this.KeySizeValue / 8];
Utils.StaticRandomNumberGenerator.GetBytes(this.KeyValue);
while (TripleDES.IsWeakKey(this.KeyValue))
{
Utils.StaticRandomNumberGenerator.GetBytes(this.KeyValue);
}
}
static internal byte[] GetStrongKey()
{
int size = DESTransform.BLOCK_BYTE_SIZE * 3;
byte[] key = KeyBuilder.Key(size);
while (TripleDES.IsWeakKey(key))
{
key = KeyBuilder.Key(size);
}
return(key);
}
/// <include file='doc\TripleDESCryptoServiceProvider.uex' path='docs/doc[@for="TripleDESCryptoServiceProvider.GenerateKey"]/*' />
public override void GenerateKey()
{
// respect KeySizeValue
KeyValue = new byte[KeySizeValue / 8];
RNG.GetBytes(KeyValue);
// Never hand back a weak or semi-weak key
while (TripleDES.IsWeakKey(KeyValue))
{
RNG.GetBytes(KeyValue);
}
}
internal static byte[] GetStrongKey()
{
int size = DESTransform.BLOCK_BYTE_SIZE * 3;
byte[] array = KeyBuilder.Key(size);
while (TripleDES.IsWeakKey(array))
{
array = KeyBuilder.Key(size);
}
return(array);
}
public TripleDESTransform(TripleDES algo, bool encryption, byte[] key, byte[] iv) : base(algo, encryption, iv)
{
#if NET_2_0
if (key == null)
{
key = GetStrongKey();
}
#endif
// note: checking weak keys also checks valid key length
if (TripleDES.IsWeakKey(key))
{
string msg = Locale.GetText("This is a known weak key.");
throw new CryptographicException(msg);
}
byte[] key1 = new byte [8];
byte[] key2 = new byte [8];
byte[] key3 = new byte [8];
DES des = DES.Create();
Buffer.BlockCopy(key, 0, key1, 0, 8);
Buffer.BlockCopy(key, 8, key2, 0, 8);
if (key.Length == 16)
{
Buffer.BlockCopy(key, 0, key3, 0, 8);
}
else
{
Buffer.BlockCopy(key, 16, key3, 0, 8);
}
// note: some modes (like CFB) requires encryption when decrypting
if ((encryption) || (algo.Mode == CipherMode.CFB))
{
E1 = new DESTransform(des, true, key1, iv);
D2 = new DESTransform(des, false, key2, iv);
E3 = new DESTransform(des, true, key3, iv);
}
else
{
D1 = new DESTransform(des, false, key3, iv);
E2 = new DESTransform(des, true, key2, iv);
D3 = new DESTransform(des, false, key1, iv);
}
}
public TripleDESTransform(TripleDES algo, bool encryption, byte[] key, byte[] iv) : base(algo, encryption, iv)
{
if (key == null)
{
key = TripleDESTransform.GetStrongKey();
}
if (TripleDES.IsWeakKey(key))
{
string text = Locale.GetText("This is a known weak key.");
throw new CryptographicException(text);
}
byte[] array = new byte[8];
byte[] array2 = new byte[8];
byte[] array3 = new byte[8];
DES symmAlgo = DES.Create();
Buffer.BlockCopy(key, 0, array, 0, 8);
Buffer.BlockCopy(key, 8, array2, 0, 8);
if (key.Length == 16)
{
Buffer.BlockCopy(key, 0, array3, 0, 8);
}
else
{
Buffer.BlockCopy(key, 16, array3, 0, 8);
}
if (encryption || algo.Mode == CipherMode.CFB)
{
this.E1 = new DESTransform(symmAlgo, true, array, iv);
this.D2 = new DESTransform(symmAlgo, false, array2, iv);
this.E3 = new DESTransform(symmAlgo, true, array3, iv);
}
else
{
this.D1 = new DESTransform(symmAlgo, false, array3, iv);
this.E2 = new DESTransform(symmAlgo, true, array2, iv);
this.D3 = new DESTransform(symmAlgo, false, array, iv);
}
}
bool ICngSymmetricAlgorithm.IsWeakKey(byte[] key)
{
return(TripleDES.IsWeakKey(key));
}