Export a Private Key as a JWK

See more Private Key Examples

Demonstrates the Chilkat PrivateKey.GetJwk method, which exports the key as a compact JWK (JSON Web Key). It takes no arguments; binary values use Base64url without padding.

Note: The file paths are relative to the application's current working directory. Absolute paths may also be used. Supply the paths appropriate to your own environment.

Background: JWK is the JSON key format used across modern web security — JWT, OAuth, OpenID Connect. Exporting to it lets you publish a key into a JWK Set or hand it to a web framework that speaks JWK. Note this is the private JWK: it includes the private parameters (d and, for RSA, the CRT values), so it is highly sensitive — publish only the public JWK derived from ToPublicKey when sharing.

Chilkat C Downloads

Download Chilkat for C

#include <C_CkPrivateKey.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkPrivateKey privKey;
    const char *jwk;

    success = FALSE;

    //  Load a private key to export.
    privKey = CkPrivateKey_Create();
    success = CkPrivateKey_LoadPemFile(privKey,"qa_data/private.pem");
    if (success == FALSE) {
        printf("%s\n",CkPrivateKey_lastErrorText(privKey));
        CkPrivateKey_Dispose(privKey);
        return;
    }

    //  Export as a compact JWK (JSON Web Key).  Binary values use Base64url without padding.
    jwk = CkPrivateKey_getJwk(privKey);
    if (CkPrivateKey_getLastMethodSuccess(privKey) == FALSE) {
        printf("%s\n",CkPrivateKey_lastErrorText(privKey));
        CkPrivateKey_Dispose(privKey);
        return;
    }

    printf("%s\n",jwk);


    CkPrivateKey_Dispose(privKey);

    }