C++

Duplicate OpensSSL Command that Decrypts Binary DER

See more OpenSSL Examples

This example duplicates the following:

openssl smime -decrypt -in INPUT_FILE -inform der -binary -out OUTPUT_FILE -recip PEM_CERT_AND_KEY -passin pass:PRIVKEY_PASSWORD

Note: Although "smime" is the OpenSSL command, we're not really dealing with S/MIME. The arguments "-inform der -binary" indicate that the input is simply the binary DER (i.e. the PKCS7 binary encrypted object). The output can be any type of file (whatever was encrypted).

C++

#include <CkCrypt2.h>
#include <CkPem.h>
#include <CkPrivateKey.h>
#include <CkCert.h>

void ChilkatSample(void)
    {
    bool success = false;

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

    CkCrypt2 crypt;

    crypt.put_CryptAlgorithm("pki");

    CkPem pem;
    success = pem.LoadPemFile("qa_data/pem/myPem.pem","password");
    if (success == false) {
        std::cout << pem.lastErrorText() << "\r\n";
        return;
    }

    CkPrivateKey privkey;
    success = pem.PrivateKeyAt(0,privkey);
    if (success == false) {
        std::cout << pem.lastErrorText() << "\r\n";
        return;
    }

    CkCert cert;
    success = pem.CertAt(0,cert);
    if (success == false) {
        std::cout << pem.lastErrorText() << "\r\n";
        return;
    }

    success = crypt.SetDecryptCert2(cert,privkey);
    if (success == false) {
        std::cout << crypt.lastErrorText() << "\r\n";
        return;
    }

    success = crypt.CkDecryptFile("qa_data/infile.enc","qa_output/outfile.dat");
    if (success == false) {
        std::cout << crypt.lastErrorText() << "\r\n";
        return;
    }

    std::cout << "Success." << "\r\n";
    }