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).

Dim fso, outFile
Set fso = CreateObject("Scripting.FileSystemObject")
'Create a Unicode (utf-16) output text file.
Set outFile = fso.CreateTextFile("output.txt", True, True)

set crypt = CreateObject("Chilkat.Crypt2")

'  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.
set json = CreateObject("Chilkat.JsonObject")
success = json.UpdateString("variant","argon2id")
success = json.UpdateInt("memoryCostKb",131072)
success = json.UpdateInt("iterations",4)
success = json.UpdateInt("parallelism",2)
success = 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.
success = json.UpdateString("secret","application-wide-pepper")
success = json.UpdateString("secretEncoding","utf-8")

phcHash = crypt.Argon2HashPassword(password,json.Emit())
If (crypt.LastMethodSuccess = 0) Then
    outFile.WriteLine(crypt.LastErrorText)
    WScript.Quit
End If

outFile.WriteLine(phcHash)

outFile.Close