public static StoredPassword From(byte[] hash, byte[] salt, TargetHashConfigration opts)
{
return(new StoredPassword
{
Hash = hash,
Salt = salt,
Options = opts,
});
}
public Task <byte[]> Hash(byte[] password, byte[] salt, TargetHashConfigration options)
{
return(Task.Factory.StartNew(() =>
KeyDerivation.Pbkdf2(
password: BitConverter.ToString(password),
salt: salt,
prf: Prf(options),
iterationCount: options.IterationCount ?? throw new InvalidOperationException($"{nameof(options.IterationCount)} required for PBKDF2"),
numBytesRequested: options.PasswordHashBytes ?? throw new InvalidOperationException($"{nameof(options.PasswordHashBytes)} required for PBKDF2"))
));
}
public Task <byte[]> Hash(byte[] password, byte[] salt, TargetHashConfigration options)
{
switch (options.Algorithm ?? throw new InvalidOperationException($"{nameof(options.Algorithm)} required for hashing passwords"))
{
case HashingAlgorithm.SHA1:
return(sha1.Hash(password, salt, options));
case HashingAlgorithm.PBKDF2:
return(pbkdf2.Hash(password, salt, options));
default:
throw new NotImplementedException($"Hashing algorithm {options.Algorithm} not yet implemented");
}
}
public async Task <byte[]> Hash(byte[] password, byte[] salt, TargetHashConfigration options)
{
using (var stream = new MemoryStream(password.Length + salt.Length))
{
await stream.WriteAsync(password, 0, password.Length);
await stream.WriteAsync(salt, 0, salt.Length);
stream.Seek(0, SeekOrigin.Begin);
using (var sha = new SHA1CryptoServiceProvider())
{
return(sha.ComputeHash(stream));
}
}
}
private KeyDerivationPrf Prf(TargetHashConfigration options)
{
switch (options.Algorithm2 ?? throw new InvalidOperationException($"{nameof(options.IterationCount)} required for PBKDF2"))
{
case HashingAlgorithm.SHA1:
return(KeyDerivationPrf.HMACSHA1);
case HashingAlgorithm.SHA256:
return(KeyDerivationPrf.HMACSHA256);
case HashingAlgorithm.SHA512:
return(KeyDerivationPrf.HMACSHA512);
default:
throw new IndexOutOfRangeException($"{options.Algorithm2.Value} is unsupported Algorithm2 for PBKDF2");
}
}