(C) Export Digital Certificate's Public Key

The ExportPublicKey method can be called to get a certificate's public key. It can then be saved to any of a number of formats: (1) OpenSSL DER, (2) OpenSSL PEM, (3) RSA DER, (4) XML.

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#include <C_CkCert.h>
#include <C_CkPublicKey.h>

void ChilkatSample(void)
    {
    HCkCert cert;
    BOOL success;
    HCkPublicKey pubkey;

    cert = CkCert_Create();

    // LoadFromFile will load virtually any certificate format file.
    // It will auto-recognize the format and load appropiately.
    success = CkCert_LoadFromFile(cert,"/Users/chilkat/testData/cer/chilkat.cer");
    if (success != TRUE) {
        printf("%s\n",CkCert_lastErrorText(cert));
        CkCert_Dispose(cert);
        return;
    }

    // Get the public key:

    pubkey = CkCert_ExportPublicKey(cert);
    if (CkCert_getLastMethodSuccess(cert) == FALSE) {
        printf("%s\n",CkCert_lastErrorText(cert));
        CkCert_Dispose(cert);
        return;
    }

    // Save to various formats:
    success = CkPublicKey_SaveDerFile(pubkey,FALSE,"/Users/chilkat/testData/pubkeys/chilkat_pkcs8.der");
    if (success != TRUE) {
        printf("%s\n",CkPublicKey_lastErrorText(pubkey));
        CkPublicKey_Dispose(pubkey);
        CkCert_Dispose(cert);
        return;
    }

    success = CkPublicKey_SavePemFile(pubkey,FALSE,"/Users/chilkat/testData/pubkeys/chilkat.pem");
    if (success != TRUE) {
        printf("%s\n",CkPublicKey_lastErrorText(pubkey));
        CkPublicKey_Dispose(pubkey);
        CkCert_Dispose(cert);
        return;
    }

    success = CkPublicKey_SaveDerFile(pubkey,TRUE,"/Users/chilkat/testData/pubkeys/chilkat_pkcs1.der");
    if (success != TRUE) {
        printf("%s\n",CkPublicKey_lastErrorText(pubkey));
        CkPublicKey_Dispose(pubkey);
        CkCert_Dispose(cert);
        return;
    }

    success = CkPublicKey_SaveXmlFile(pubkey,"/Users/chilkat/testData/pubkeys/chilkat.xml");
    if (success != TRUE) {
        printf("%s\n",CkPublicKey_lastErrorText(pubkey));
        CkPublicKey_Dispose(pubkey);
        CkCert_Dispose(cert);
        return;
    }

    CkPublicKey_Dispose(pubkey);
    printf("Public key exported to all file formats.\n");


    CkCert_Dispose(cert);

    }