Xbase++ Requires Chilkat v11.0.0+

Duplicate openssl dgst -sha256 -verify pubKey.pem -signature signature.sig in.dat

See more OpenSSL Examples

Demonstrates how to duplicate this OpenSSL command:

openssl dgst -sha256 -verify pubKey.pem -signature signature.sig in.dat

The in.dat file contains the original data that was signed, and can contain text or binary data of any type. The above OpenSSL command does the following:

1. Creates a SHA256 digest of the contents of the input file.
2. Verifies the SHA256 digest using the public key.

Xbase++

LOCAL nSuccess
LOCAL oPubKey
LOCAL oBdFileData
LOCAL oBdSig
LOCAL oRsa

nSuccess := 0

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

oPubKey := CreateObject("Chilkat.PublicKey")

//  Load the public key from an PEM file:
nSuccess := oPubKey:LoadFromFile("pubKey.pem")
IF (nSuccess == 0)
    ? oPubKey:LastErrorText
    oPubKey:destroy()
    RETURN
ENDIF

//  Load the data of the original file that was signed.
oBdFileData := CreateObject("Chilkat.BinData")
nSuccess := oBdFileData:LoadFile("in.dat")

//  Load the signature.
oBdSig := CreateObject("Chilkat.BinData")
nSuccess := oBdSig:LoadFile("signature.sig")

oRsa := CreateObject("Chilkat.Rsa")

//  Import the public key into the RSA component:
nSuccess := oRsa:UsePublicKey(oPubKey)
IF (nSuccess == 0)
    ? oRsa:LastErrorText
    oPubKey:destroy()
    oBdFileData:destroy()
    oBdSig:destroy()
    oRsa:destroy()
    RETURN
ENDIF

//  OpenSSL uses big-endian.
oRsa:LittleEndian := 0

nSuccess := oRsa:VerifyBd(oBdFileData, "sha256", oBdSig)
IF (nSuccess != 1)
    ? oRsa:LastErrorText
    ? "The signature was invalid."
    oPubKey:destroy()
    oBdFileData:destroy()
    oBdSig:destroy()
    oRsa:destroy()
    RETURN
ENDIF

? "The signature was verified."

oPubKey:destroy()
oBdFileData:destroy()
oBdSig:destroy()
oRsa:destroy()