(VB.NET UWP/WinRT) Ed25519 Sign and Verify

Demonstrates how to create an Ed25519 signature, and then to verify it.

Note: This example requires Chilkat v9.5.0.83 or greater.

Chilkat Universal Windows Platform (UWP) / WinRT Downloads Chilkat for the Universal Windows Platform (UWP)

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

Dim privKeyHex As String = "1498b5467a63dffa2dc9d9e069caf075d16fc33fdd4c3b01bfadae6433767d93"
Dim pubKeyHex As String = "b7a3c12dc0c8c748ab07525b701122b88bd78f600c76342d27f25e5f92444cde"

Dim privKey As New Chilkat.PrivateKey
' This example shows only one way of loading an Ed25519 private key.
' Chilkat can load other formats (JWK, PEM, ASN.1 DER, etc.)  
' You may do so by calling LoadAnyFormat or LoadAnyFormatFile.
Dim success As Boolean = privKey.LoadEd25519(privKeyHex,pubKeyHex)
If (success = False) Then
    Debug.WriteLine(privKey.LastErrorText)
    Exit Sub
End If


' The data to be signed...
Dim bd As New Chilkat.BinData
bd.AppendString("Message for Ed25519 signing","utf-8")

Dim eddsa As New Chilkat.EdDSA
Dim hexSig As String = eddsa.SignBdENC(bd,"hexlower",privKey)

Debug.WriteLine("signature = " & hexSig)

' The expected output is: 6dd355667fae4eb43c6e0ab92e870edb2de0a88cae12dbd8591507f584fe4912babff497f1b8edf9567d2483d54ddc6459bea7855281b7a246a609e3001a4e08


' Verify the signature..
Dim pubKey As New Chilkat.PublicKey
success = pubKey.LoadEd25519(pubKeyHex)
If (success = False) Then
    Debug.WriteLine(pubKey.LastErrorText)
    Exit Sub
End If


Dim bVerified As Boolean = eddsa.VerifyBdENC(bd,hexSig,"hexlower",pubKey)
If (bVerified = False) Then
    Debug.WriteLine(eddsa.LastErrorText)
    Debug.WriteLine("Failed to verify the signature.")
    Exit Sub
End If



Debug.WriteLine("The Ed25519 signature is verified!")