public virtual byte[] Unwrap(byte[] input, int inOff, int length)
{
if (this.forWrapping)
{
throw new InvalidOperationException("Not set for unwrapping");
}
if (input == null)
{
throw new InvalidCipherTextException("Null pointer as ciphertext");
}
int blockSize = this.engine.GetBlockSize();
if (length % blockSize != 0)
{
throw new InvalidCipherTextException("Ciphertext not multiple of " + blockSize);
}
ParametersWithIV parameters = new ParametersWithIV(this.param, DesEdeWrapEngine.IV2);
this.engine.Init(false, parameters);
byte[] array = new byte[length];
for (int num = 0; num != array.Length; num += blockSize)
{
this.engine.ProcessBlock(input, inOff + num, array, num);
}
byte[] array2 = DesEdeWrapEngine.reverse(array);
this.iv = new byte[8];
byte[] array3 = new byte[array2.Length - 8];
Array.Copy(array2, 0, this.iv, 0, 8);
Array.Copy(array2, 8, array3, 0, array2.Length - 8);
this.paramPlusIV = new ParametersWithIV(this.param, this.iv);
this.engine.Init(false, this.paramPlusIV);
byte[] array4 = new byte[array3.Length];
for (int num2 = 0; num2 != array4.Length; num2 += blockSize)
{
this.engine.ProcessBlock(array3, num2, array4, num2);
}
byte[] array5 = new byte[array4.Length - 8];
byte[] array6 = new byte[8];
Array.Copy(array4, 0, array5, 0, array4.Length - 8);
Array.Copy(array4, array4.Length - 8, array6, 0, 8);
if (!this.CheckCmsKeyChecksum(array5, array6))
{
throw new InvalidCipherTextException("Checksum inside ciphertext is corrupted");
}
return(array5);
}
private void WrapTest(
int id,
byte[] kek,
byte[] iv,
byte[] input,
byte[] output)
{
IWrapper wrapper = new DesEdeWrapEngine();
wrapper.Init(true, new ParametersWithIV(new DesEdeParameters(kek), iv));
try
{
byte[] cText = wrapper.Wrap(input, 0, input.Length);
if (!AreEqual(cText, output))
{
Fail(": failed wrap test " + id + " expected " + Hex.ToHexString(output)
+ " got " + Hex.ToHexString(cText));
}
}
catch (Exception e)
{
Fail("failed wrap test exception: " + e.ToString(), e);
}
wrapper.Init(false, new DesEdeParameters(kek));
try
{
byte[] pText = wrapper.Unwrap(output, 0, output.Length);
if (!AreEqual(pText, input))
{
Fail("failed unwrap test " + id + " expected " + Hex.ToHexString(input)
+ " got " + Hex.ToHexString(pText));
}
}
catch (Exception e)
{
Fail("failed unwrap test exception: " + e.ToString(), e);
}
}
public virtual byte[] Wrap(byte[] input, int inOff, int length)
{
if (!this.forWrapping)
{
throw new InvalidOperationException("Not initialized for wrapping");
}
byte[] array = new byte[length];
Array.Copy(input, inOff, array, 0, length);
byte[] array2 = this.CalculateCmsKeyChecksum(array);
byte[] array3 = new byte[array.Length + array2.Length];
Array.Copy(array, 0, array3, 0, array.Length);
Array.Copy(array2, 0, array3, array.Length, array2.Length);
int blockSize = this.engine.GetBlockSize();
if (array3.Length % blockSize != 0)
{
throw new InvalidOperationException("Not multiple of block length");
}
this.engine.Init(true, this.paramPlusIV);
byte[] array4 = new byte[array3.Length];
for (int num = 0; num != array3.Length; num += blockSize)
{
this.engine.ProcessBlock(array3, num, array4, num);
}
byte[] array5 = new byte[this.iv.Length + array4.Length];
Array.Copy(this.iv, 0, array5, 0, this.iv.Length);
Array.Copy(array4, 0, array5, this.iv.Length, array4.Length);
byte[] array6 = DesEdeWrapEngine.reverse(array5);
ParametersWithIV parameters = new ParametersWithIV(this.param, DesEdeWrapEngine.IV2);
this.engine.Init(true, parameters);
for (int num2 = 0; num2 != array6.Length; num2 += blockSize)
{
this.engine.ProcessBlock(array6, num2, array6, num2);
}
return(array6);
}
