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 crypt As New Chilkat.Crypt2

//  The password should come from a secure source rather than being hard-coded.
Dim password As String
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.
Dim json As New Chilkat.JsonObject
Dim success As Boolean
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")

Dim phcHash As String
phcHash = crypt.Argon2HashPassword(password,json.Emit())
If (crypt.LastMethodSuccess = False) Then
    System.DebugLog(crypt.LastErrorText)
    Return
End If

System.DebugLog(phcHash)