public static byte[] Decrypt(
byte[] encryptedData,
byte[] pass,
byte[] salt,
CryptConfigFileHelperScryptParameters scryptParameters = null)
{
if (encryptedData == null || pass == null || salt == null)
{
throw new ArgumentNullException();
}
var keyIvGenerated = GenKeyAndIv(pass, salt, scryptParameters);
try
{
return(keyIvGenerated.DecryptData(encryptedData));
}
catch (EnumException <AesKeyIvPair.EDecryptDataErrCodes> enumExc)
{
if (enumExc.ExceptionCode == AesKeyIvPair.EDecryptDataErrCodes.WrongKey)
{
throw EnumException.Create(EDecryptErrCodes.WrongPassword,
innerException: enumExc);
}
throw;
}
}
public T1 GetValue <T1>(
byte[] pass,
CryptConfigFileHelperScryptParameters scryptParameters = null
)
{
try
{
return(Encoding.UTF8.GetString(CryptConfigFileHelper.Decrypt(
EncryptedData,
pass,
Salt,
scryptParameters
)).ParseJsonToType <T1>());
}
catch (EnumException <CryptConfigFileHelper.EDecryptErrCodes> enumExc)
{
if (enumExc.ExceptionCode == CryptConfigFileHelper.EDecryptErrCodes.WrongPassword)
{
throw EnumException.Create(
EGetValueT1ErrCodes.WrongPassword,
innerException: enumExc
);
}
throw;
}
}
public byte[] DecryptData(
byte[] encryptedData
)
{
var key = Key;
Assert.NotNull(key);
var iv = Iv;
Assert.NotNull(iv);
using (var aesAlg = new AesManaged())
{
aesAlg.Key = key;
aesAlg.IV = iv;
ICryptoTransform decryptor
= aesAlg.CreateDecryptor(
aesAlg.Key,
aesAlg.IV
);
/**/
using (var input = new MemoryStream(encryptedData))
{
using (var output = new MemoryStream(
encryptedData.Length + 32)
)
{
using (var disposableBuffer = new TempByteArray(4096))
{
var buffer = disposableBuffer.Data;
try
{
using (
var csDecrypt = new CryptoStream(
input,
decryptor,
CryptoStreamMode.Read
)
)
{
var read = csDecrypt.Read(buffer, 0, buffer.Length);
while (read > 0)
{
output.Write(buffer, 0, read);
read = csDecrypt.Read(buffer, 0, buffer.Length);
}
}
}
catch (CryptographicException cryptExc)
{
throw EnumException.Create(
EDecryptDataErrCodes.WrongKey,
innerException: cryptExc
);
}
}
var totalLength = (int)output.Length;
if (totalLength < 32)
{
throw EnumException.Create(
EDecryptDataErrCodes.WrongEncryptedDataLength);
}
output.Seek(0, SeekOrigin.Begin);
using (
var reader = new EndianBinaryReader(
_littleConverter,
output
)
)
{
using (
var tempDataHash
= new TempByteArray(
reader.ReadBytesOrThrow(32)
)
)
{
var data = reader.ReadBytesOrThrow(totalLength - 32);
using (var mySha256 = new SHA256Managed())
{
var computedDataHash
= mySha256.ComputeHash(data);
if (
tempDataHash.Data.SequenceEqual(
computedDataHash
)
)
{
return(data);
}
}
throw EnumException.Create(
EDecryptDataErrCodes.WrongDecryptedDataHash
);
}
}
}
}
}
}