public MAC16 AESDecryptMAC(CipherV2 cipherV2, RandomKey32 randomKey, IVCache ivCache, LongRunningOperationContext context)
{
Guard.NotNull(new object[] { cipherV2, randomKey, context });
byte[] macBytes;
if (cipherV2.RoundsExponent.Value == RoundsExponent.DontMakeRounds)
{
macBytes = this._platform.ComputeAESRound(AESDir.Decrpyt, cipherV2.IV16.GetBytes(), cipherV2.MACCipher16.GetBytes(), randomKey.GetBytes());
}
else
{
context.EncryptionProgress.Message = LocalizableStrings.MsgDecryptingMAC;
macBytes = ComputeAESWithRounds(AESDir.Decrpyt, cipherV2.IV16, cipherV2.MACCipher16.GetBytes(), randomKey.GetBytes(), cipherV2.RoundsExponent.Value, ivCache, context);
}
return(new MAC16(macBytes));
}
/// <summary>
/// Purpose:
/// </summary>
/// <param name="iv"></param>
/// <param name="roundsExp"></param>
/// <returns></returns>
public IVCache CreateIVTable(IV16 iv, byte roundsExp)
{
Guard.NotNull(new object[] { iv });
var ivCache = new IVCache();
var rounds = 1u << roundsExp;
var ivRounds = rounds;
var ivTable = new byte[rounds][];
byte[] ivInput = iv.GetBytes();
while (ivRounds > 0)
{
ivTable[ivTable.Length - ivRounds] = ivInput;
ivInput = this._platform.ComputeSHA256(ivInput).Take(16).ToArray();
ivRounds = ivRounds - 1;
}
ivCache.IVTable = new Tuple <byte[], byte[][]>(iv.GetBytes(), ivTable);
return(ivCache);
}
public void AESEncryptMessageWithRandomKey(PaddedData paddedData, RandomKey32 randomKey, CipherV2 cipherV2, IVCache ivCache, LongRunningOperationContext context)
{
Guard.NotNull(new object[] { paddedData, randomKey, cipherV2, context });
cipherV2.PlaintextPadding = paddedData.PlaintextPadding;
if (cipherV2.RoundsExponent.Value == RoundsExponent.DontMakeRounds)
{
Debug.Assert(ivCache == null);
cipherV2.MessageCipher = new MessageCipher(this._platform.ComputeAESRound(AESDir.Encrypt, cipherV2.IV16.GetBytes(), paddedData.GetBytes(), randomKey.GetBytes()));
}
else
{
context.EncryptionProgress.Message = LocalizableStrings.MsgEncryptingMessage;
cipherV2.MessageCipher = new MessageCipher(ComputeAESWithRounds(AESDir.Encrypt, cipherV2.IV16, paddedData.GetBytes(), randomKey.GetBytes(), cipherV2.RoundsExponent.Value, ivCache, context));
}
}
public void AESEncryptRandomKeyWithInputDerivedKey(InputDerivedKey32 inputDerivedKey, RandomKey32 randomKey, CipherV2 cipherV2, IVCache ivCache, LongRunningOperationContext context)
{
Guard.NotNull(new object[] { inputDerivedKey, randomKey, cipherV2, context });
if (cipherV2.RoundsExponent.Value == RoundsExponent.DontMakeRounds)
{
Debug.Assert(ivCache == null);
cipherV2.RandomKeyCipher32 = new RandomKeyCipher32(this._platform.ComputeAESRound(AESDir.Encrypt, cipherV2.IV16.GetBytes(), randomKey.GetBytes(), inputDerivedKey.GetBytes()));
}
else
{
context.EncryptionProgress.Message = LocalizableStrings.MsgEncryptingRandomKey;
cipherV2.RandomKeyCipher32 = new RandomKeyCipher32(ComputeAESWithRounds(AESDir.Encrypt, cipherV2.IV16, randomKey.GetBytes(), inputDerivedKey.GetBytes(), cipherV2.RoundsExponent.Value, ivCache, context));
}
}
public PaddedData AESDecryptMessage(CipherV2 cipherV2, IV16 iv16, RandomKey32 randomKey, IVCache ivCache, LongRunningOperationContext context)
{
Guard.NotNull(new object[] { cipherV2, iv16, randomKey, context });
byte[] paddedDataBytes;
if (cipherV2.RoundsExponent.Value == RoundsExponent.DontMakeRounds)
{
paddedDataBytes = this._platform.ComputeAESRound(AESDir.Decrpyt, cipherV2.IV16.GetBytes(), cipherV2.MessageCipher.GetBytes(), randomKey.GetBytes());
}
else
{
context.EncryptionProgress.Message = LocalizableStrings.MsgDecryptingMessage;
paddedDataBytes = ComputeAESWithRounds(AESDir.Decrpyt, cipherV2.IV16, cipherV2.MessageCipher.GetBytes(), randomKey.GetBytes(), cipherV2.RoundsExponent.Value, ivCache, context);
}
return(new PaddedData(paddedDataBytes, cipherV2.PlaintextPadding));
}
public RandomKey32 AESDecryptRandomKeyWithPasswordDerivedKey(CipherV2 cipherV2, InputDerivedKey32 inputDerivedKey, IVCache ivCache, LongRunningOperationContext context)
{
Guard.NotNull(new object[] { cipherV2, inputDerivedKey, context });
byte[] randomKeyBytes;
if (cipherV2.RoundsExponent.Value == RoundsExponent.DontMakeRounds)
{
randomKeyBytes = this._platform.ComputeAESRound(AESDir.Decrpyt, cipherV2.IV16.GetBytes(), cipherV2.RandomKeyCipher32.GetBytes(), inputDerivedKey.GetBytes());
}
else
{
context.EncryptionProgress.Message = LocalizableStrings.MsgDecryptingRandomKey;
randomKeyBytes = ComputeAESWithRounds(AESDir.Decrpyt, cipherV2.IV16, cipherV2.RandomKeyCipher32.GetBytes(), inputDerivedKey.GetBytes(), cipherV2.RoundsExponent.Value, ivCache, context);
}
return(new RandomKey32(randomKeyBytes));
}
byte[] ComputeAESWithRounds(AESDir aesDir, IV16 iv, byte[] dataBytes, byte[] keyBytes, byte roundsExp, IVCache ivCache, LongRunningOperationContext context)
{
Guard.NotNull(new object[] { aesDir, iv, dataBytes, keyBytes, roundsExp, ivCache, context });
var rounds = 1u << roundsExp;
var roundsToGo = rounds;
byte[] inputData = dataBytes;
byte[] aesResult = null;
while (roundsToGo > 0)
{
byte[] currentIV =
aesDir == AESDir.Encrypt
? ivCache.IVTable.Item2[roundsToGo - 1]
: ivCache.IVTable.Item2[ivCache.IVTable.Item2.Length - roundsToGo];
aesResult = this._platform.ComputeAESRound(aesDir, currentIV, inputData, keyBytes);
inputData = aesResult;
roundsToGo--; // decrement before calculating the percentage or we'll be stuck at 99%
// START encryptionProgress / Cancellation
context.CancellationToken.ThrowIfCancellationRequested();
decimal progressValue = (rounds - roundsToGo) / (decimal)(rounds);
context.EncryptionProgress.Percent = (int)(progressValue * 100m);
context.EncryptionProgress.Report(context.EncryptionProgress);
// END encryptionProgress
}
return(aesResult);
}
public void AESEncryptMACWithRandomKey(CipherV2 cipherV2, MAC16 mac, RandomKey32 randomKey, IVCache ivCache, LongRunningOperationContext context)
{
Guard.NotNull(new object[] { cipherV2, mac, randomKey, context });
if (cipherV2.RoundsExponent.Value == RoundsExponent.DontMakeRounds)
{
Debug.Assert(ivCache == null);
cipherV2.MACCipher16 = new MACCipher16(this._platform.ComputeAESRound(AESDir.Encrypt, cipherV2.IV16.GetBytes(), mac.GetBytes(), randomKey.GetBytes()));
}
else
{
context.EncryptionProgress.Message = LocalizableStrings.MsgEncryptingMAC;
cipherV2.MACCipher16 = new MACCipher16(ComputeAESWithRounds(AESDir.Encrypt, cipherV2.IV16, mac.GetBytes(), randomKey.GetBytes(), cipherV2.RoundsExponent.Value, ivCache, context));
}
}
