VBScript

Ed25519ph Sign and Verify

See more Ed25519 Examples

Demonstrates how to create an Ed25519ph signature, and then to verify it.

Note: This example requires Chilkat v9.5.0.91 or greater.

VBScript

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

success = 0

' This example assumes the Chilkat API to have been previously unlocked.
' See Global Unlock Sample for sample code.

' Use the following test vector from https://www.rfc-editor.org/rfc/rfc8032#page-30

'    -----TEST abc
' 
'    ALGORITHM:
'    Ed25519ph
' 
'    SECRET KEY:
'    833fe62409237b9d62ec77587520911e
'    9a759cec1d19755b7da901b96dca3d42
' 
'    PUBLIC KEY:
'    ec172b93ad5e563bf4932c70e1245034
'    c35467ef2efd4d64ebf819683467e2bf
' 
'    MESSAGE (length 3 bytes):
'    616263
' 
'    SIGNATURE:
'    98a70222f0b8121aa9d30f813d683f80
'    9e462b469c7ff87639499bb94e6dae41
'    31f85042463c2a355a2003d062adf5aa
'    a10b8c61e636062aaad11c2a26083406

privKeyHex = "833fe62409237b9d62ec77587520911e9a759cec1d19755b7da901b96dca3d42"
pubKeyHex = "ec172b93ad5e563bf4932c70e1245034c35467ef2efd4d64ebf819683467e2bf"

set privKey = CreateObject("Chilkat.PrivateKey")
success = privKey.LoadEd25519(privKeyHex,pubKeyHex)
If (success = 0) Then
    outFile.WriteLine(privKey.LastErrorText)
    WScript.Quit
End If

' The data to be signed...
set bd = CreateObject("Chilkat.BinData")
success = bd.AppendEncoded("616263","hex")

set eddsa = CreateObject("Chilkat.EdDSA")
' Indicate we want the Ed25519ph instance.
eddsa.Algorithm = "Ed25519ph"

hexSig = eddsa.SignBdENC(bd,"hexlower",privKey)

outFile.WriteLine("signature = " & hexSig)

' The expected output is: 98a70222f0b8121aa9d30f813d683f80....

' Verify the signature..
set pubKey = CreateObject("Chilkat.PublicKey")
success = pubKey.LoadEd25519(pubKeyHex)
If (success = 0) Then
    outFile.WriteLine(pubKey.LastErrorText)
    WScript.Quit
End If

bVerified = eddsa.VerifyBdENC(bd,hexSig,"hexlower",pubKey)
If (bVerified = 0) Then
    outFile.WriteLine(eddsa.LastErrorText)
    outFile.WriteLine("Failed to verify the signature.")
    WScript.Quit
End If

outFile.WriteLine("The Ed25519ph signature is verified!")

outFile.Close