(Visual FoxPro) 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 ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

LOCAL lcPrivKeyHex
LOCAL lcPubKeyHex
LOCAL loPrivKey
LOCAL lnSuccess
LOCAL loBd
LOCAL loEddsa
LOCAL lcHexSig
LOCAL loPubKey
LOCAL lnBVerified

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

lcPrivKeyHex = "1498b5467a63dffa2dc9d9e069caf075d16fc33fdd4c3b01bfadae6433767d93"
lcPubKeyHex = "b7a3c12dc0c8c748ab07525b701122b88bd78f600c76342d27f25e5f92444cde"

* For versions of Chilkat < 10.0.0, use CreateObject('Chilkat_9_5_0.PrivateKey')
loPrivKey = CreateObject('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.
lnSuccess = loPrivKey.LoadEd25519(lcPrivKeyHex,lcPubKeyHex)
IF (lnSuccess = 0) THEN
    ? loPrivKey.LastErrorText
    RELEASE loPrivKey
    CANCEL
ENDIF

* The data to be signed...
* For versions of Chilkat < 10.0.0, use CreateObject('Chilkat_9_5_0.BinData')
loBd = CreateObject('Chilkat.BinData')
loBd.AppendString("Message for Ed25519 signing","utf-8")

* For versions of Chilkat < 10.0.0, use CreateObject('Chilkat_9_5_0.EdDSA')
loEddsa = CreateObject('Chilkat.EdDSA')
lcHexSig = loEddsa.SignBdENC(loBd,"hexlower",loPrivKey)

? "signature = " + lcHexSig

* The expected output is: 6dd355667fae4eb43c6e0ab92e870edb2de0a88cae12dbd8591507f584fe4912babff497f1b8edf9567d2483d54ddc6459bea7855281b7a246a609e3001a4e08

* Verify the signature..
* For versions of Chilkat < 10.0.0, use CreateObject('Chilkat_9_5_0.PublicKey')
loPubKey = CreateObject('Chilkat.PublicKey')
lnSuccess = loPubKey.LoadEd25519(lcPubKeyHex)
IF (lnSuccess = 0) THEN
    ? loPubKey.LastErrorText
    RELEASE loPrivKey
    RELEASE loBd
    RELEASE loEddsa
    RELEASE loPubKey
    CANCEL
ENDIF

lnBVerified = loEddsa.VerifyBdENC(loBd,lcHexSig,"hexlower",loPubKey)
IF (lnBVerified = 0) THEN
    ? loEddsa.LastErrorText
    ? "Failed to verify the signature."
    RELEASE loPrivKey
    RELEASE loBd
    RELEASE loEddsa
    RELEASE loPubKey
    CANCEL
ENDIF

? "The Ed25519 signature is verified!"

RELEASE loPrivKey
RELEASE loBd
RELEASE loEddsa
RELEASE loPubKey