Xbase++ Requires Chilkat v11.0.0+

Generate RSA Key and Sign a String

See more RSA Examples

Demonstrates how to generate a new RSA public/private key pair and use it to generate a signature for a string. The (binary) digital signature is returned as a hexidecimalized string. Xbase++

LOCAL nSuccess
LOCAL oRsa
LOCAL oPrivKey
LOCAL cStrData
LOCAL cHexSig
LOCAL oPubKey

nSuccess := 0

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

oRsa := CreateObject("Chilkat.Rsa")

//  Generate a 2048-bit RSA key.
oPrivKey := CreateObject("Chilkat.PrivateKey")
nSuccess := oRsa:GenKey(2048, oPrivKey)

oRsa:UsePrivateKey(oPrivKey)

//  Return the signature in hex.
oRsa:EncodingMode := "hex"

cStrData := "This is the string to be signed."

//  Sign the SHA256 hash of the string.
cHexSig := oRsa:SignStringENC(cStrData, "sha256")

? cHexSig

//  Now verify the signature:
oPubKey := CreateObject("Chilkat.PublicKey")
oPrivKey:ToPublicKey(oPubKey)
oRsa:UsePublicKey(oPubKey)

nSuccess := oRsa:VerifyStringENC(cStrData, "sha256", cHexSig)
IF (nSuccess == 1)
    ? "Signature verified!"
ELSE
    ? oRsa:LastErrorText
ENDIF

//  Try it with an invalid signature:
nSuccess := oRsa:VerifyStringENC(cStrData, "sha256", "not a valid sig")
IF (nSuccess == 1)
    ? "Signature verified!"
ELSE
    ? "Signature validation failed!"
ENDIF

//  Try it with invalid data:
nSuccess := oRsa:VerifyStringENC("Not the original data", "sha256", cHexSig)
IF (nSuccess == 1)
    ? "Signature verified!"
ELSE
    ? "Signature validation failed!"
ENDIF

oRsa:destroy()
oPrivKey:destroy()
oPubKey:destroy()