[Sql-Server]what data type to use for password salt and hash values and what length?

Question

I am generating salt and hash values from my passwords by using,

string salt = CreateSalt(TxtPassword.Text.Length);
string hash = CreatePasswordHash(TxtPassword.Text, salt);

private static string CreateSalt(int size)
{
    //Generate a cryptographic random number.
    RNGCryptoServiceProvider rng = new RNGCryptoServiceProvider();
    byte[] buff = new byte[size];
    rng.GetBytes(buff);

    // Return a Base64 string representation of the random number.
    return Convert.ToBase64String(buff);
}

private static string CreatePasswordHash(string pwd, string salt)
{
    string saltAndPwd = String.Concat(pwd, salt);
    string hashedPwd =
     FormsAuthentication.HashPasswordForStoringInConfigFile(
     saltAndPwd, "sha1");

    return hashedPwd;
}

What datatype you would suggest for storing these values in sql server? Any suggestion...

Salt:9GsPWpFD

Hash:E778AF0DC5F2953A00B35B35D80F6262CDBB8567

Answer 1

ASPNET_DB says this - can't go wrong.

Password nvarchar(128) NOT NULL,
PasswordSalt nvarchar(128) NOT NULL,

while 128 may seem like a lot, various types of encryption can result in larger strings than you started out with. There is absolutely no reason not to follow the lead of the very smart people who have spend thousands of man hours developing the asp.net membership system.

Answer 2

We store our passwords as a binary SHA512 hash