/// <summary>Generates a hash based on a key, salt and personal bytes</summary>
/// <returns><c>byte</c> hashed message</returns>
/// <param name="message">Message.</param>
/// <param name="key">Key.</param>
/// <param name="salt">Salt.</param>
/// <param name="personal">Personal string.</param>
/// <param name="bytes">The size (in bytes) of the desired result.</param>
/// <exception cref="ArgumentNullException"></exception>
/// <exception cref="KeyOutOfRangeException"></exception>
/// <exception cref="SaltOutOfRangeException"></exception>
/// <exception cref="PersonalOutOfRangeException"></exception>
public static byte[] HashSaltPersonal(byte[] message, byte[] key, byte[] salt, byte[] personal,
int bytes = OUT_BYTES)
{
if (message == null)
{
throw new ArgumentNullException("message", "Message cannot be null");
}
if (salt == null)
{
throw new ArgumentNullException("salt", "Salt cannot be null");
}
if (personal == null)
{
throw new ArgumentNullException("personal", "Personal string cannot be null");
}
if (key != null && (key.Length > KEY_BYTES_MAX || key.Length < KEY_BYTES_MIN))
{
throw new KeyOutOfRangeException(string.Format("key must be between {0} and {1} bytes in length.",
KEY_BYTES_MIN, KEY_BYTES_MAX));
}
if (key == null)
{
key = new byte[0];
}
if (salt.Length != SALT_BYTES)
{
throw new SaltOutOfRangeException(string.Format("Salt must be {0} bytes in length.", SALT_BYTES));
}
if (personal.Length != PERSONAL_BYTES)
{
throw new PersonalOutOfRangeException(string.Format("Personal bytes must be {0} bytes in length.",
PERSONAL_BYTES));
}
//validate output length
if (bytes > BYTES_MAX || bytes < BYTES_MIN)
{
throw new BytesOutOfRangeException("bytes", bytes,
string.Format("bytes must be between {0} and {1} bytes in length.", BYTES_MIN, BYTES_MAX));
}
var buffer = new byte[bytes];
SodiumLibrary.crypto_generichash_blake2b_salt_personal(buffer, buffer.Length, message, message.LongLength,
key, key.Length, salt, personal);
return(buffer);
}