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).

use chilkat();

$crypt = chilkat::CkCrypt2->new();

#  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 = chilkat::CkJsonObject->new();
$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->get_LastMethodSuccess() == 0) {
    print $crypt->lastErrorText() . "\r\n";
    exit;
}

print $phcHash . "\r\n";