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C++

Sign a JWS with a Private Key

See more JSON Web Signatures (JWS) Examples

Demonstrates Jws.SetPrivateKey, which sets the private key used to create a signature. The example uses RS256 (RSASSA-PKCS1-v1_5 with SHA-256).

The file path is relative to the application's current working directory. An absolute path may also be used. Supply the path appropriate to your own environment.

Background. Public-key JWS signs with a private key so that anyone holding the corresponding public key can verify the signature.

Chilkat C++ Downloads

C++
#include <CkJws.h>
#include <CkJsonObject.h>
#include <CkPrivateKey.h>

void ChilkatSample(void)
    {
    bool success = false;

    CkJws jws;

    //  Protected header specifying RSASSA-PKCS1-v1_5 with SHA-256 (RS256).
    CkJsonObject header;
    header.UpdateString("alg","RS256");
    success = jws.SetProtectedHeader(0,header);
    if (success == false) {
        std::cout << jws.lastErrorText() << "\r\n";
        return;
    }

    bool bIncludeBom = false;
    success = jws.SetPayload("This is the content to sign.","utf-8",bIncludeBom);
    if (success == false) {
        std::cout << jws.lastErrorText() << "\r\n";
        return;
    }

    //  The file path is relative to the application's current working directory.  An absolute path
    //  may also be used.  Supply the path appropriate to your own environment.
    //  Load the signer's private key and set it for signature 0.
    CkPrivateKey privKey;
    success = privKey.LoadPemFile("qa_data/signer_privkey.pem");
    if (success == false) {
        std::cout << privKey.lastErrorText() << "\r\n";
        return;
    }

    success = jws.SetPrivateKey(0,privKey);
    if (success == false) {
        std::cout << jws.lastErrorText() << "\r\n";
        return;
    }

    const char *jwsCompact = jws.createJws();
    if (jws.get_LastMethodSuccess() == false) {
        std::cout << jws.lastErrorText() << "\r\n";
        return;
    }

    std::cout << jwsCompact << "\r\n";
    }