private static byte[] DecryptKey(KeyStoreV3 <Pbkdf2Params> keystore, string password)
{
if (ReferenceEquals(keystore, null))
{
throw new ArgumentNullException(nameof(keystore));
}
if (password.IsNullOrEmpty())
{
throw new ArgumentNullException(nameof(password));
}
var crypto = keystore.crypto;
var kdfparams = crypto.kdfparams;
// unsupported cipher
if (crypto.cipher != CIPHER)
{
throw new ArgumentException("unsupported cipher");
}
// unsupported prf
if (kdfparams.prf != Pbkdf2Params.HMACSHA256)
{
throw new ArgumentException("unsupported kdfparams.prf");
}
return(PbkdfCrypt.DecryptPbkdf2Sha256(password, Hex.ToByteArray(crypto.mac),
HexToByteArray(crypto.cipherparams.iv),
HexToByteArray(crypto.ciphertext),
kdfparams.c, kdfparams.salt.ToByteArray(), kdfparams.dklen));
}
internal static PrivateKey DecryptKey(KeyStoreV3 <Pbkdf2Params> keyStore, string password)
{
if (string.IsNullOrEmpty(password))
{
throw new KdfException(ErrorCode.BAD_ARGUMENT, "empty password");
}
if (ReferenceEquals(keyStore, null))
{
throw new KdfException(ErrorCode.BAD_ARGUMENT, "keyStore is null");
}
var crypto = keyStore.crypto;
var kdfparams = keyStore.crypto.kdfparams;
// unsupported cipher
if (crypto.cipher != CIPHER)
{
throw new KdfException(ErrorCode.UNSUPPORTED, $"unsupported cipher:{crypto.cipher}");
}
// unsupported prf
if (kdfparams.prf != Pbkdf2Params.HMACSHA256)
{
throw new KdfException(ErrorCode.UNSUPPORTED, $"unsupported kdfparams.prf:{kdfparams.prf}");
}
var key = PbkdfCrypt.DecryptPbkdf2Sha256(password, crypto.mac.HexToBytes(),
crypto.cipherparams.iv.HexToBytes(),
crypto.ciphertext.HexToBytes(),
kdfparams.c, kdfparams.salt.HexToBytes(), kdfparams.dklen);
return(new PrivateKey(key));
}
internal static KeyStoreV3 <Pbkdf2Params> EncryptKey(PrivateKey key, string password, Pbkdf2Params kdfParams)
{
if (ReferenceEquals(key, null))
{
throw new KdfException(ErrorCode.BAD_ARGUMENT, "empty key");
}
if (string.IsNullOrEmpty(password))
{
throw new KdfException(ErrorCode.BAD_ARGUMENT, "empty password");
}
// unsupported prf
if (kdfParams.prf != Pbkdf2Params.HMACSHA256)
{
throw new KdfException(ErrorCode.UNSUPPORTED, $"unsupported kdfparams.prf:{kdfParams.prf}");
}
// random values ( salt, iv )
var salt = kdfParams.salt;
var cipherParams = new CipherParams();
// derivedKey -> cipherKey -> cipherText -> mac
var derivedKey = PbkdfCrypt.GeneratePbkdf2Sha256DerivedKey(password, salt.HexToBytes(), kdfParams.c, kdfParams.dklen);
var cipherKey = PbkdfCrypt.GenerateCipherKey(derivedKey);
var cipherText = PbkdfCrypt.GenerateAesCtrCipher(cipherParams.iv.HexToBytes(), cipherKey, key.Bytes);
var mac = PbkdfCrypt.GenerateMac(derivedKey, cipherText);
return(new KeyStoreV3 <Pbkdf2Params>()
{
version = Version,
id = Guid.NewGuid().ToString(),
address = key.Address.HexAddress.ToLower(),
crypto =
{
ciphertext = cipherText.ToHex(),
cipherparams = cipherParams,
cipher = CIPHER,
kdf = KdfType.pbkdf2.ToString(),
kdfparams = kdfParams,
mac = mac.ToHex()
}
});
}
private static KeyStoreV3 <Pbkdf2Params> EncryptKey(byte[] key, string address, string password, Pbkdf2Params kdfParams)
{
if (key.IsNullOrEmpty())
{
throw new ArgumentNullException(nameof(key));
}
if (password.IsNullOrEmpty())
{
throw new ArgumentNullException(nameof(password));
}
// unsupported prf
if (kdfParams.prf != Pbkdf2Params.HMACSHA256)
{
throw new ArgumentException("unsupported kdfparams.prf");
}
// random values ( salt, iv )
var salt = kdfParams.salt;
var cipherParams = new CipherParams();
// derivedKey -> cipherKey -> cipherText -> mac
var derivedKey = PbkdfCrypt.GeneratePbkdf2Sha256DerivedKey(password, salt.ToByteArray(), kdfParams.c, kdfParams.dklen);
var cipherKey = PbkdfCrypt.GenerateCipherKey(derivedKey);
var cipherText = PbkdfCrypt.GenerateAesCtrCipher(cipherParams.iv.ToByteArray(), cipherKey, key);
var mac = PbkdfCrypt.GenerateMac(derivedKey, cipherText);
return(new KeyStoreV3 <Pbkdf2Params>()
{
version = Version,
id = Guid.NewGuid().ToString(),
address = address,
crypto =
{
ciphertext = cipherText.ToHexString(),
cipherparams = cipherParams,
cipher = CIPHER,
kdf = KdfType.pbkdf2.ToString(),
kdfparams = kdfParams,
mac = mac.ToHexString()
}
});
}
