C++

Export a Public Key as DER into a BinData

Demonstrates the Chilkat PublicKey.GetDerBd method, which writes the public key as binary DER into a BinData. The first argument selects the representation (as for GetPem) and the second is the BinData that receives the bytes (its contents are replaced).

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: The in-memory binary export: the raw DER lands in a BinData ready to hash, transmit, or hand to another API without a temporary file. It is the BinData counterpart to the text exporters, and the first argument picks the same PKCS #1 versus SubjectPublicKeyInfo structure.

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C++

#include <CkPublicKey.h>
#include <CkBinData.h>

void ChilkatSample(void)
    {
    bool success = false;

    //  Load a public key to export.  LoadFromFile inspects the content, so it accepts DER, PEM, XML,
    //  JWK, and other supported representations.
    CkPublicKey pubKey;
    success = pubKey.LoadFromFile("qa_data/public.pem");
    if (success == false) {
        std::cout << pubKey.lastErrorText() << "\r\n";
        return;
    }

    //  Write the public key as binary DER into a BinData.  The 1st argument selects the representation
    //  (as for GetPem) and the 2nd is the BinData that receives the bytes (its contents are replaced).
    bool preferPkcs1 = false;
    CkBinData bd;
    success = pubKey.GetDerBd(preferPkcs1,bd);
    if (success == false) {
        std::cout << pubKey.lastErrorText() << "\r\n";
        return;
    }

    std::cout << "Exported " << bd.get_NumBytes() << " DER bytes." << "\r\n";
    }