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.

$oCrypt = ObjCreate("Chilkat.Crypt2")

;  The password should come from a secure source rather than being hard-coded.
Local $sPassword = "correct horse battery staple"

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

;  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.
$oJson = ObjCreate("Chilkat.JsonObject")
$oJson.UpdateString("secret","application-wide-pepper")
$oJson.UpdateString("secretEncoding","utf-8")

;  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.
$oJson.UpdateInt("maxMemoryKb",262144)

;  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.
Local $iVerifyResult = $oCrypt.Argon2VerifyPassword($sPassword,$oJson.Emit(),$sPhcHash)
If ($iVerifyResult = 1) Then
    ConsoleWrite("The password is verified." & @CRLF)
Else
    If ($iVerifyResult = 0) Then
        ConsoleWrite("The password does not match." & @CRLF)
    Else
        ConsoleWrite("The verification could not be performed: " & $oCrypt.LastErrorText & @CRLF)
    EndIf

EndIf