Verify an Argon2 Password with a Secret and Memory Guard

Demonstrates Crypt2.Argon2VerifyPassword when the hash was created with a secret (pepper) or ad, and the use of maxMemoryKb to guard against untrusted hash strings.

Use ChilkatAx-win32.pkg

Procedure Test
    Handle hoCrypt
    String sPassword
    String sPhcHash
    Handle hoJson
    Boolean iSuccess
    Integer iVerifyResult
    String sTemp1

    Get Create (RefClass(cComChilkatCrypt2)) To hoCrypt
    If (Not(IsComObjectCreated(hoCrypt))) Begin
        Send CreateComObject of hoCrypt
    End

    //  The password should come from a secure source rather than being hard-coded.
    Move "correct horse battery staple" To sPassword

    Move "$argon2id$v=19$m=131072,t=4,p=2$c29tZXJhbmRvbXNhbHQ$3fJ7v1qKcVJ0lHqXjBQZ8mYm3sNTfSPRt0bqDl9kEyM" To sPhcHash

    //  When the hash was created with a secret (pepper) or ad, the same values must be supplied to verify.
    //  Only the secret, ad, encoding, passwordCharset, and maxMemoryKb members of the options are used;
    //  everything else is ignored.
    Get Create (RefClass(cComChilkatJsonObject)) To hoJson
    If (Not(IsComObjectCreated(hoJson))) Begin
        Send CreateComObject of hoJson
    End
    Get ComUpdateString Of hoJson "secret" "application-wide-pepper" To iSuccess
    Get ComUpdateString Of hoJson "secretEncoding" "utf-8" To iSuccess

    //  maxMemoryKb guards against a hash from an untrusted source claiming an enormous memory cost.  The
    //  memory cost is taken from the hash string, so this limit is checked before any memory is allocated.
    //  It defaults to 2 GB.
    Get ComUpdateInt Of hoJson "maxMemoryKb" 262144 To iSuccess

    //  Argon2VerifyPassword returns 1 if the password matched, 0 if it did not match, and -1 if the
    //  verification could not be performed.  Always test for a match with == 1.
    Get ComEmit Of hoJson To sTemp1
    Get ComArgon2VerifyPassword Of hoCrypt sPassword sTemp1 sPhcHash To iVerifyResult
    If (iVerifyResult = 1) Begin
        Showln "The password is verified."
    End
    Else Begin
        If (iVerifyResult = 0) Begin
            Showln "The password does not match."
        End
        Else Begin
            Get ComLastErrorText Of hoCrypt To sTemp1
            Showln "The verification could not be performed: " sTemp1
        End

    End



End_Procedure