// --------------------------------------------------------------------------------
// Private definition of the hash operation used by this class. It is:
//
// SHA1( message-text + random-salt + static-salt )
//
// NOTE: We convert the inputted byte arrays into strings for code simplicity.
// (Probably slower than assembling a byte buffer with byte array copies.)
// --------------------------------------------------------------------------------
private static byte[] _hash3(byte[] text, byte[] saltR, byte[] saltS, Krypto.HashAlgoID algo)
{
switch (algo) {
case Krypto.HashAlgoID.SHA1:
return Krypto.hash_sha1(ArrayOp.Append<byte>(text, saltR, saltS));
case Krypto.HashAlgoID.PBKDF2:
return Krypto.PBKDF2( text, ArrayOp.Append<byte>(saltR, saltS), 2112, 32);
default:
throw new System.ArgumentException( "_hash3: invalid HashAlgoID", String.Format( "{0}",algo ));
}
}
// --------------------------------------------------------------------------------
// Creates the hash and returns
// NOTE: Why didn't I made this a constructor instead of a static function?
// --------------------------------------------------------------------------------
public static HashStore Create(byte[] text, byte[] saltStatic, Krypto.HashAlgoID algo)
{
// Create a new random salt for every hash store instance.
byte[] saltRandom = Krypto.RandomBytes(16);
// Hash a string made from the random salt, static salt, and text.
byte[] hash = _hash3(text, saltRandom, saltStatic, algo);
// Return a key store containing both the hash and the random salt.
return new HashStore(hash, saltRandom, algo);
}
public static HashStore Create(string text, byte[] saltStatic, Krypto.HashAlgoID algo)
{
return Create(Encoding.UTF8.GetBytes(text), saltStatic, algo);
}
// private constructor for packing pieces parts together.
private HashStore(byte[] hash, byte[] salt, Krypto.HashAlgoID algo)
{
this.hash = hash;
this.salt = salt;
this.algo = algo;
}