Hash a Password with Argon2 (Tuned Options)

Demonstrates Crypt2.Argon2HashPassword with explicit options: the cost parameters, saltLen (how many random salt bytes to generate when no salt is given), and an optional secret (pepper).

var
crypt: TChilkatCrypt2;
password: WideString;
json: TChilkatJsonObject;
phcHash: WideString;

begin
crypt := TChilkatCrypt2.Create(Self);

//  The password should come from a secure source rather than being hard-coded.
password := 'correct horse battery staple';

//  The Argon2 options are the same members as Argon2DeriveKey, except the salt is optional for
//  hashing.  When no "salt" is given, a random salt is generated; "saltLen" (default 16, range 8..1024)
//  sets how many random bytes to use.
json := TChilkatJsonObject.Create(Self);
json.UpdateString('variant','argon2id');
json.UpdateInt('memoryCostKb',131072);
json.UpdateInt('iterations',4);
json.UpdateInt('parallelism',2);
json.UpdateInt('saltLen',16);

//  A secret (pepper) and/or ad may be used, but neither is stored in the returned PHC string.  The
//  same values must be supplied to Argon2VerifyPassword for the password to verify.
json.UpdateString('secret','application-wide-pepper');
json.UpdateString('secretEncoding','utf-8');

phcHash := crypt.Argon2HashPassword(password,json.Emit());
if (crypt.LastMethodSuccess = 0) then
  begin
    Memo1.Lines.Add(crypt.LastErrorText);
    Exit;
  end;
Memo1.Lines.Add(phcHash);