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Lianja 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.

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Lianja
llSuccess = .F.

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

loRsa = createobject("CkRsa")

//  Generate a 2048-bit RSA key.
loPrivKey = createobject("CkPrivateKey")
llSuccess = loRsa.GenKey(2048,loPrivKey)

loRsa.UsePrivateKey(loPrivKey)

//  Return the signature in hex.
loRsa.EncodingMode = "hex"

lcStrData = "This is the string to be signed."

//  Sign the SHA256 hash of the string.
lcHexSig = loRsa.SignStringENC(lcStrData,"sha256")

? lcHexSig

//  Now verify the signature:
loPubKey = createobject("CkPublicKey")
loPrivKey.ToPublicKey(loPubKey)
loRsa.UsePublicKey(loPubKey)

llSuccess = loRsa.VerifyStringENC(lcStrData,"sha256",lcHexSig)
if (llSuccess = .T.) then
    ? "Signature verified!"
else
    ? loRsa.LastErrorText
endif

//  Try it with an invalid signature:
llSuccess = loRsa.VerifyStringENC(lcStrData,"sha256","not a valid sig")
if (llSuccess = .T.) then
    ? "Signature verified!"
else
    ? "Signature validation failed!"
endif

//  Try it with invalid data:
llSuccess = loRsa.VerifyStringENC("Not the original data","sha256",lcHexSig)
if (llSuccess = .T.) then
    ? "Signature verified!"
else
    ? "Signature validation failed!"
endif



release loRsa
release loPrivKey
release loPubKey