(Lianja) 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.

Chilkat Lianja Extension Download Chilkat Lianja Extension

// 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.
llSuccess = loRsa.GenerateKey(2048)

// To 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
? loRsa.LastErrorText

// Now verify the signature:
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
    ? loRsa.LastErrorText
endif

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

// Try it with the wrong hash algorithm:
llSuccess = loRsa.VerifyStringENC(lcStrData,"sha-1",lcHexSig)
if (llSuccess = .T.) then
    ? "Signature verified!"
else
    ? loRsa.LastErrorText
endif



release loRsa