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).

func chilkatTest() {
    let crypt = CkoCrypt2()!

    //  The password should come from a secure source rather than being hard-coded.
    var password: String? = "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.
    let json = CkoJsonObject()!
    json.updateString(jsonPath: "variant", value: "argon2id")
    json.updateInt(jsonPath: "memoryCostKb", value: 131072)
    json.updateInt(jsonPath: "iterations", value: 4)
    json.updateInt(jsonPath: "parallelism", value: 2)
    json.updateInt(jsonPath: "saltLen", value: 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(jsonPath: "secret", value: "application-wide-pepper")
    json.updateString(jsonPath: "secretEncoding", value: "utf-8")

    var phcHash: String? = crypt.argon2HashPassword(password: password, json: json.emit())
    if crypt.lastMethodSuccess == false {
        print("\(crypt.lastErrorText!)")
        return
    }

    print("\(phcHash!)")

}