public void Decrypt()
{
try
{
if (Constants.IsRc4)
{
Client.Decrypt(m_vData);
if (m_vType == 10101)
{
Client.State = ClientState.Login;
}
// No need since the decryption occurs on same buffer.
//SetData(m_vData);
}
else
{
if (m_vType == 10101)
{
var cipherText = m_vData;
Client.CPublicKey = cipherText.Take(32).ToArray();
var blake = Blake2B.Create(new Blake2BConfig
{
OutputSizeInBytes = 24
});
blake.Init();
blake.Update(Client.CPublicKey);
blake.Update(Key.Crypto.PublicKey);
Client.CRNonce = blake.Finish();
cipherText = CustomNaCl.OpenPublicBox(cipherText.Skip(32).ToArray(), Client.CRNonce, Key.Crypto.PrivateKey, Client.CPublicKey);
Client.CSharedKey = Client.CPublicKey;
Client.CSessionKey = cipherText.Take(24).ToArray();
Client.CSNonce = cipherText.Skip(24).Take(24).ToArray();
Client.State = ClientState.Login;
SetData(cipherText.Skip(48).ToArray());
}
else
{
if (m_vType != 10100)
{
if (Client.State == ClientState.LoginSuccess)
{
Client.CSNonce.Increment();
SetData(CustomNaCl.OpenSecretBox(new byte[16].Concat(m_vData).ToArray(), Client.CSNonce, Client.CSharedKey));
}
}
}
}
}
catch
{
Client.State = ClientState.Exception;
throw;
}
}
public static void crypto_sign_keypair(byte[] pk, int pkoffset, byte[] sk, int skoffset, byte[] seed, int seedoffset)
{
GroupElementP3 A;
int i;
Array.Copy(seed, seedoffset, sk, skoffset, 32);
var blake2bConfig = new Blake2BConfig
{
OutputSizeInBytes = 64
};
var hasher = Blake2B.Create(blake2bConfig);
hasher.Update(sk, skoffset, 32);
byte[] h = hasher.Finish();
//byte[] h = Sha512.Hash(sk, skoffset, 32);//ToDo: Remove alloc
ScalarOperations.sc_clamp(h, 0);
GroupOperations.ge_scalarmult_base(out A, h, 0);
GroupOperations.ge_p3_tobytes(pk, pkoffset, ref A);
for (i = 0; i < 32; ++i)
{
sk[skoffset + 32 + i] = pk[pkoffset + i];
}
CryptoBytes.Wipe(h);
}
public void Decrypt()
{
try
{
if (m_vType == 10101)
{
byte[] cipherText = m_vData;
Client.CPublicKey = cipherText.Take(32).ToArray();
Hasher b = Blake2B.Create(new Blake2BConfig
{
OutputSizeInBytes = 24
});
b.Init();
b.Update(Client.CPublicKey);
b.Update(Key.Crypto.PublicKey);
Client.CRNonce = b.Finish();
cipherText = CustomNaCl.OpenPublicBox(cipherText.Skip(32).ToArray(), Client.CRNonce, Key.Crypto.PrivateKey, Client.CPublicKey);
Client.CSharedKey = Client.CPublicKey;
Client.CSessionKey = cipherText.Take(24).ToArray();
Client.CSNonce = cipherText.Skip(24).Take(24).ToArray();
Client.CState = 1;
SetData(cipherText.Skip(48).ToArray());
}
else if (m_vType != 10100)
{
Client.CSNonce.Increment();
SetData(CustomNaCl.OpenSecretBox(new byte[16].Concat(m_vData).ToArray(), Client.CSNonce, Client.CSharedKey));
}
}
catch (Exception ex)
{
Client.CState = 0;
}
}
public string EncodeAccount(UInt256 account)
{
var hasher = Blake2B.Create(new Blake2BConfig
{
OutputSizeInBytes = 5
});
var bytes = account.ToByteArray().Reverse().ToArray();
hasher.Update(bytes);
byte[] checkBytes = hasher.Finish();
Array.Resize(ref checkBytes, 8);
UInt64 check = BitConverter.ToUInt64(checkBytes, 0);
BigInteger number = Number(bytes);
number <<= 40;
number |= new BigInteger(check);
StringBuilder sb = new StringBuilder();
for (int i = 0; i < 60; i++)
{
var r = number.ToByteArray()[0] & 0x1f;
number >>= 5;
sb.Append(AccountLookup[r]);
}
sb.Append("_brx");
var addrReverse = sb.ToString();
var arr = addrReverse.ToCharArray();
Array.Reverse(arr);
return(new string(arr));
}
public void Encrypt(byte[] plainText)
{
try
{
if (GetMessageType() == 20104 || GetMessageType() == 20103)
{
Hasher b = Blake2B.Create(new Blake2BConfig
{
OutputSizeInBytes = 24
});
b.Init();
b.Update(Client.CSNonce);
b.Update(Client.CPublicKey);
b.Update(Key.Crypto.PublicKey);
SetData(CustomNaCl.CreatePublicBox(Client.CRNonce.Concat(Client.CSharedKey).Concat(plainText).ToArray(), b.Finish(), Key.Crypto.PrivateKey, Client.CPublicKey));
if (GetMessageType() == 20104)
{
Client.CState = 2;
}
}
else
{
Client.CRNonce.Increment();
SetData(CustomNaCl.CreateSecretBox(plainText, Client.CRNonce, Client.CSharedKey).Skip(16).ToArray());
}
}
catch (Exception)
{
Client.CState = 0;
}
}
public bool ValidateAddress(string address)
{
if (address.Length != 64 && !address.StartsWith("xrb_"))
{
return(false);
}
var pk32 = address.Substring(4, 52);
var pk = Base32withPadding.Decode(pk32, _base32Alphabet, 4);
var checksum = address.Substring(56);
var checksumDecoded = Base32withPadding.Decode(checksum, _base32Alphabet, 0);
checksumDecoded = checksumDecoded.Reverse().ToArray();
var blake2bConfig = new Blake2BConfig
{
OutputSizeInBytes = 5
};
var hasher = Blake2B.Create(blake2bConfig);
hasher.Update(pk);
var pkChecksum = hasher.Finish();
return(pkChecksum.SequenceEqual(checksumDecoded));
}
public static string HashStateBlock(string accountAddress, string previousHash, string balance, string representativeAccount, string link)
{
var representativePublicKey = AddressToPublicKey(representativeAccount);
var accountPublicKey = AddressToPublicKey(accountAddress);
var previousBytes = HexStringToByteArray(previousHash);
var balanceHex = BigInteger.Parse(balance).ToString("X");
if (balanceHex.Length % 2 == 1)
{
balanceHex = "0" + balanceHex;
}
byte[] balanceBytes = HexStringToByteArray(balanceHex.PadLeft(32, '0'));
var linkBytes = HexStringToByteArray(link);
var preamble = HexStringToByteArray("0000000000000000000000000000000000000000000000000000000000000006");
var blake = Blake2B.Create(new Blake2BConfig()
{
OutputSizeInBytes = 32
});
blake.Init();
blake.Update(preamble);
blake.Update(accountPublicKey);
blake.Update(previousBytes);
blake.Update(representativePublicKey);
blake.Update(balanceBytes);
blake.Update(linkBytes);
var hashBytes = blake.Finish();
return(ByteArrayToHex(hashBytes));
}
public void Hash(Blake2BConfig config, byte[] message)
{
var hasher = Blake2B.Create(new Blake2BConfig()
{
OutputSizeInBytes = 64
});
hasher.Init();
hasher.Update(Previous.ToByteArray());
hasher.Update(Source.ToByteArray());
}
public static byte[] Hash(byte[] data, int size)
{
var hasher = Blake2B.Create(new Blake2BConfig
{
OutputSizeInBytes = size,
});
hasher.Init();
hasher.Update(data);
return(hasher.Finish());
}
public void Hash(Blake2BConfig config, byte[] message)
{
var hasher = Blake2B.Create(new Blake2BConfig()
{
OutputSizeInBytes = 64
});
hasher.Init();
hasher.Update(Source.ToByteArray());
hasher.Update(Representative.ToByteArray());
hasher.Update(Account.ToByteArray());
}
// Original crypto_sign_open, for reference only
/*public static int crypto_sign_open(
* byte[] m, out int mlen,
* byte[] sm, int smlen,
* byte[] pk)
* {
* byte[] h = new byte[64];
* byte[] checkr = new byte[32];
* GroupElementP3 A;
* GroupElementP2 R;
* int i;
*
* mlen = -1;
* if (smlen < 64) return -1;
* if ((sm[63] & 224) != 0) return -1;
* if (GroupOperations.ge_frombytes_negate_vartime(out A, pk, 0) != 0) return -1;
*
* for (i = 0; i < smlen; ++i) m[i] = sm[i];
* for (i = 0; i < 32; ++i) m[32 + i] = pk[i];
* Sha512BclWrapper.crypto_hash_sha512(h, m, 0, smlen);
* ScalarOperations.sc_reduce(h);
*
* var sm32 = new byte[32];
* Array.Copy(sm, 32, sm32, 0, 32);
* GroupOperations.ge_double_scalarmult_vartime(out R, h, ref A, sm32);
* GroupOperations.ge_tobytes(checkr, 0, ref R);
* if (Helpers.crypto_verify_32(checkr, sm) != 0)
* {
* for (i = 0; i < smlen; ++i)
* m[i] = 0;
* return -1;
* }
*
* for (i = 0; i < smlen - 64; ++i)
* m[i] = sm[64 + i];
* for (i = smlen - 64; i < smlen; ++i)
* m[i] = 0;
* mlen = smlen - 64;
* return 0;
* }*/
public static bool crypto_sign_verify(
byte[] sig, int sigoffset,
byte[] m, int moffset, int mlen,
byte[] pk, int pkoffset)
{
byte[] h;
byte[] checkr = new byte[32];
GroupElementP3 A;
GroupElementP2 R;
if ((sig[sigoffset + 63] & 224) != 0)
{
return(false);
}
if (GroupOperations.ge_frombytes_negate_vartime(out A, pk, pkoffset) != 0)
{
return(false);
}
var blake2bConfig = new Blake2BConfig
{
OutputSizeInBytes = 64
};
var hasher = Blake2B.Create(blake2bConfig);
hasher.Update(sig, sigoffset, 32);
hasher.Update(pk, pkoffset, 32);
hasher.Update(m, moffset, mlen);
h = hasher.Finish();
/*
* var hasher = new Sha512();
* hasher.Update(sig, sigoffset, 32);
* hasher.Update(pk, pkoffset, 32);
* hasher.Update(m, moffset, mlen);
* h = hasher.Finish();
*/
ScalarOperations.sc_reduce(h);
var sm32 = new byte[32];//todo: remove allocation
Array.Copy(sig, sigoffset + 32, sm32, 0, 32);
GroupOperations.ge_double_scalarmult_vartime(out R, h, ref A, sm32);
GroupOperations.ge_tobytes(checkr, 0, ref R);
var result = CryptoBytes.ConstantTimeEquals(checkr, 0, sig, sigoffset, 32);
CryptoBytes.Wipe(h);
CryptoBytes.Wipe(checkr);
return(result);
}
byte[] GenerateRaiAddressSeed(int index)
{
var blake2bConfig = new Blake2BConfig
{
OutputSizeInBytes = 32
};
var hasher = Blake2B.Create(blake2bConfig);
hasher.Update(Seed);
var indexBytes = BitConverter.GetBytes(index).Reverse().ToArray();
hasher.Update(indexBytes);
return(hasher.Finish());
}
public static byte[] HashAll(params byte[][] data)
{
var hasher = Blake2B.Create(new Blake2BConfig()
{
OutputSizeInBytes = 32
}, SecureArray.DefaultCall);
foreach (var d in data)
{
hasher.Update(d);
}
var hashAll = hasher.Finish();
return(hashAll);
}
public static void KeyExchange(ArraySegment <byte> sharedKey, ArraySegment <byte> publicKey, ArraySegment <byte> privateKey)
{
if (sharedKey.Array == null)
{
throw new ArgumentNullException("sharedKey.Array");
}
if (publicKey.Array == null)
{
throw new ArgumentNullException("publicKey.Array");
}
if (privateKey.Array == null)
{
throw new ArgumentNullException("privateKey");
}
if (sharedKey.Count != 32)
{
throw new ArgumentException("sharedKey.Count != 32");
}
if (publicKey.Count != 32)
{
throw new ArgumentException("publicKey.Count != 32");
}
if (privateKey.Count != 64)
{
throw new ArgumentException("privateKey.Count != 64");
}
FieldElement montgomeryX, edwardsY, edwardsZ, sharedMontgomeryX;
FieldOperations.fe_frombytes(out edwardsY, publicKey.Array, publicKey.Offset);
FieldOperations.fe_1(out edwardsZ);
MontgomeryCurve25519.EdwardsToMontgomeryX(out montgomeryX, ref edwardsY, ref edwardsZ);
var blake2bConfig = new Blake2BConfig
{
OutputSizeInBytes = 64
};
var hasher = Blake2B.Create(blake2bConfig);
hasher.Update(privateKey.Array, privateKey.Offset, 32);
byte[] h = hasher.Finish();
//byte[] h = Sha512.Hash(privateKey.Array, privateKey.Offset, 32);//ToDo: Remove alloc
ScalarOperations.sc_clamp(h, 0);
MontgomeryOperations.scalarmult(out sharedMontgomeryX, h, 0, ref montgomeryX);
CryptoBytes.Wipe(h);
FieldOperations.fe_tobytes(sharedKey.Array, sharedKey.Offset, ref sharedMontgomeryX);
MontgomeryCurve25519.KeyExchangeOutputHashNaCl(sharedKey.Array, sharedKey.Offset);
}
public UInt256 DecodeAccount(string account)
{
if (account.Length != 64)
{
throw new InvalidDataException("length should be 64");
}
if (!account.StartsWith("xrb_"))
{
throw new InvalidDataException("invalid account format");
}
BigInteger number = new BigInteger();
for (int i = 4; i < account.Length; i++)
{
sbyte byteResult = DecodeChar(account[i]);
if (byteResult != '~')
{
number <<= 5;
number += byteResult;
}
}
UInt256 accountUInt256 = new UInt256(number >> 40);
var accountBytes = accountUInt256.ToByteArray().Reverse().ToArray();
UInt64 check = BitConverter.ToUInt64(number.ToByteArray(), 0);
check &= 0xffffffffff;
var hasher = Blake2B.Create(new Blake2BConfig {
OutputSizeInBytes = 5
});
hasher.Update(accountBytes);
var final = hasher.Finish();
Array.Resize(ref final, 8);
UInt64 validation = BitConverter.ToUInt64(final, 0);
if (check != validation)
{
throw new InvalidDataException();
}
return(accountUInt256);
}
public static string PublicKeyToAddress(byte[] publicKey)
{
var address = "nano_" + NanoEncode(publicKey);
var blake = Blake2B.Create(new Blake2BConfig()
{
OutputSizeInBytes = 5
});
blake.Init();
blake.Update(publicKey);
var checksumBytes = blake.Finish();
address += NanoEncode(checksumBytes.Reverse().ToArray(), false);
return(address);
}
/// <summary>
/// Does a Blake2 hash with the ability to truncate or extend the hash to any length.
/// </summary>
/// <param name="hash">
/// The buffer to fill with the hash.
/// </param>
/// <param name="inputBuffer">
/// What to hash.
/// </param>
/// <param name="secureArrayCall">
/// The methods that get called to secure arrays. A null value defaults to <see cref="SecureArray"/>.<see cref="SecureArray.DefaultCall"/>.
/// </param>
private static void Blake2BLong(byte[] hash, byte[] inputBuffer, SecureArrayCall secureArrayCall)
{
var outputLengthBytes = new byte[4];
using var intermediateHash = SecureArray <byte> .Best(Blake2B.OutputLength, secureArrayCall);
var config = new Blake2BConfig
{
Result64ByteBuffer = intermediateHash.Buffer,
OutputSizeInBytes = hash.Length > 64 ? 64 : hash.Length,
};
Store32(outputLengthBytes, hash.Length);
using (var blakeHash = Blake2B.Create(config, secureArrayCall))
{
blakeHash.Update(outputLengthBytes);
blakeHash.Update(inputBuffer);
blakeHash.Finish();
}
if (hash.Length <= intermediateHash.Buffer.Length)
{
Array.Copy(intermediateHash.Buffer, hash, hash.Length);
return;
}
const int b2B2 = Blake2B.OutputLength / 2;
Array.Copy(intermediateHash.Buffer, hash, b2B2);
int pos = b2B2;
int lastHashIndex = hash.Length - Blake2B.OutputLength;
var toHash = new byte[Blake2B.OutputLength];
while (pos < lastHashIndex)
{
Array.Copy(intermediateHash.Buffer, toHash, intermediateHash.Buffer.Length);
Blake2B.ComputeHash(toHash, config, secureArrayCall);
Array.Copy(intermediateHash.Buffer, 0, hash, pos, b2B2);
pos += b2B2;
}
Array.Copy(intermediateHash.Buffer, toHash, intermediateHash.Buffer.Length);
Blake2B.ComputeHash(toHash, config, secureArrayCall);
Array.Copy(intermediateHash.Buffer, 0, hash, pos, hash.Length - pos);
}
public void Encrypt(byte[] plainText)
{
try
{
if (Constants.IsRc4)
{
Client.Encrypt(plainText);
if (m_vType == 20104)
{
Client.State = Client.ClientState.LoginSuccess;
}
SetData(plainText);
}
else
{
if (m_vType == 20104 || m_vType == 20103)
{
Hasher b = Blake2B.Create(new Blake2BConfig
{
OutputSizeInBytes = 24
});
b.Init();
b.Update(Client.CSNonce);
b.Update(Client.CPublicKey);
b.Update(Key.Crypto.PublicKey);
SetData(CustomNaCl.CreatePublicBox(Client.CRNonce.Concat(Client.CSharedKey).Concat(plainText).ToArray(), b.Finish(), Key.Crypto.PrivateKey, Client.CPublicKey));
if (m_vType == 20104)
{
Client.State = Client.ClientState.LoginSuccess;
}
}
else
{
Client.CRNonce.Increment();
SetData(CustomNaCl.CreateSecretBox(plainText, Client.CRNonce, Client.CSharedKey).Skip(16).ToArray());
}
}
}
catch (Exception)
{
Client.State = ClientState.Exception;
}
}
public string PublicAddress(int index = 0)
{
var addressSeed = GenerateRaiAddressSeed(index);
var pk = Ed25519.PublicKeyFromSeed(addressSeed);
var pk32 = Base32withPadding.Encode(pk, _base32Alphabet, 260);
var blake2bConfig = new Blake2BConfig
{
OutputSizeInBytes = 5
};
var hasher = Blake2B.Create(blake2bConfig);
hasher.Update(pk);
var checksum = hasher.Finish().Reverse().ToArray();
var checksum32 = Base32withPadding.Encode(checksum, _base32Alphabet, 40);
return($"xrb_{pk32}{checksum32}");
}
/*public static void crypto_sign(
* byte[] sm, out int smlen,
* byte[] m, int mlen,
* byte[] sk
* )
* {
* byte[] az = new byte[64];
* byte[] r = new byte[64];
* byte[] hram = new byte[64];
* GroupElementP3 R;
* int i;
*
* Helpers.crypto_hash_sha512(az, sk, 0, 32);
* az[0] &= 248;
* az[31] &= 63;
* az[31] |= 64;
*
* smlen = mlen + 64;
* for (i = 0; i < mlen; ++i) sm[64 + i] = m[i];
* for (i = 0; i < 32; ++i) sm[32 + i] = az[32 + i];
* Helpers.crypto_hash_sha512(r, sm, 32, mlen + 32);
* for (i = 0; i < 32; ++i) sm[32 + i] = sk[32 + i];
*
* ScalarOperations.sc_reduce(r);
* GroupOperations.ge_scalarmult_base(out R, r, 0);
* GroupOperations.ge_p3_tobytes(sm, 0, ref R);
*
* Helpers.crypto_hash_sha512(hram, sm, 0, mlen + 64);
* ScalarOperations.sc_reduce(hram);
* var sm32 = new byte[32];
* Array.Copy(sm, 32, sm32, 0, 32);
* ScalarOperations.sc_muladd(sm32, hram, az, r);
* Array.Copy(sm32, 0, sm, 32, 32);
* }*/
public static void crypto_sign2(
byte[] sig, int sigoffset,
byte[] m, int moffset, int mlen,
byte[] sk, int skoffset)
{
byte[] az;
byte[] r;
byte[] hram;
GroupElementP3 R;
var blake2bConfig = new Blake2BConfig
{
OutputSizeInBytes = 64
};
var hasher = Blake2B.Create(blake2bConfig);
//var hasher = new Sha512();
{
hasher.Update(sk, skoffset, 32);
az = hasher.Finish();
ScalarOperations.sc_clamp(az, 0);
hasher.Init();
hasher.Update(az, 32, 32);
hasher.Update(m, moffset, mlen);
r = hasher.Finish();
ScalarOperations.sc_reduce(r);
GroupOperations.ge_scalarmult_base(out R, r, 0);
GroupOperations.ge_p3_tobytes(sig, sigoffset, ref R);
hasher.Init();
hasher.Update(sig, sigoffset, 32);
hasher.Update(sk, skoffset + 32, 32);
hasher.Update(m, moffset, mlen);
hram = hasher.Finish();
ScalarOperations.sc_reduce(hram);
var s = new byte[32]; //todo: remove allocation
Array.Copy(sig, sigoffset + 32, s, 0, 32);
ScalarOperations.sc_muladd(s, hram, az, r);
Array.Copy(s, 0, sig, sigoffset + 32, 32);
CryptoBytes.Wipe(s);
}
}
public static bool AddressIsValid(string address)
{
byte[] pubkeyBytes = AddressToPublicKey(address);
if (pubkeyBytes == null)
{
return(false);
}
var blake = Blake2B.Create(new Blake2BConfig()
{
OutputSizeInBytes = 5
});
blake.Init();
blake.Update(pubkeyBytes);
var hashBytes = blake.Finish();
// Checksum is last 8 characters, compare
var checksum = address.Substring(address.Length - 8, 8);
var binaryString = "";
for (int i = 0; i < checksum.Length; i++)
{
// Decode each character into string representation of it's binary parts
binaryString += nano_addressEncoding[checksum[i]];
}
// Convert to bytes
var pk = new byte[5];
for (int i = 0; i < 5; i++)
{
// for each byte, read the bits from the binary string
var b = Convert.ToByte(binaryString.Substring(i * 8, 8), 2);
pk[i] = b;
}
return(hashBytes.SequenceEqual(pk.Reverse()));
}
public void Splits()
{
var hasher = Blake2B.Create();
for (int len = 0; len <= 256; len++)
{
hasher.Init();
hasher.Update(input, 0, len);
string hash0 = BitConverter.ToString(hasher.Finish());
for (int split1 = 0; split1 <= len; split1++)
{
for (int split2 = split1; split2 <= len; split2++)
{
hasher.Init();
hasher.Update(input, 0, split1);
hasher.Update(input, split1, split2 - split1);
hasher.Update(input, split2, len - split2);
string hash1 = BitConverter.ToString(hasher.Finish());
Assert.AreEqual(hash0, hash1);
}
}
}
}
private SecureArray <byte> InitialHash()
{
var ret = BestSecureArray <byte>(Blake2B.OutputLength);
using (var blakeHash =
Blake2B.Create(
new Blake2BConfig
{
OutputSizeInBytes = PrehashDigestLength,
Result64ByteBuffer = ret.Buffer
}))
{
var value = new byte[4];
Store32(value, this.config.Lanes);
blakeHash.Update(value);
Store32(value, this.config.HashLength);
blakeHash.Update(value);
Store32(value, this.config.MemoryCost);
blakeHash.Update(value);
Store32(value, this.config.TimeCost);
blakeHash.Update(value);
Store32(value, (uint)this.config.Version);
blakeHash.Update(value);
Store32(value, (uint)this.config.Type);
blakeHash.Update(value);
Store32(value, this.config.Password?.Length ?? 0);
blakeHash.Update(value);
if (this.config.Password != null)
{
blakeHash.Update(this.config.Password);
if (this.config.ClearPassword)
{
SecureArray.Zero(this.config.Password);
}
}
Store32(value, this.config.Salt?.Length ?? 0);
blakeHash.Update(value);
if (this.config.Salt != null)
{
blakeHash.Update(this.config.Salt);
}
Store32(value, this.config.Secret?.Length ?? 0);
blakeHash.Update(value);
if (this.config.Secret != null)
{
blakeHash.Update(this.config.Secret);
if (this.config.ClearSecret)
{
SecureArray.Zero(this.config.Secret);
}
}
Store32(value, this.config.AssociatedData?.Length ?? 0);
blakeHash.Update(value);
if (this.config.AssociatedData != null)
{
blakeHash.Update(this.config.AssociatedData);
}
blakeHash.Finish();
}
return(ret);
}
