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C++

Duplicate openssl smime -encrypt -binary -aes-256-cbc -in some_file.dat -out some_file.dat.enc -outform DER cert.crt

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Demonstrates how to encrypt to binary DER using 256-bit AES (CBC mode) as the underlying symmetric encryption algorithm, to produce PKCS7 enveloped data (binary DER).

Duplicates the following openssl command:

openssl smime -encrypt -binary -aes-256-cbc -in some_file.dat -out some_file.dat.enc -outform DER cert.crt

Chilkat C++ Downloads

C++
#include <CkCert.h>
#include <CkBinData.h>
#include <CkCrypt2.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.

    CkCert cert;
    success = cert.LoadFromFile("qa_data/openssl/EE.cer");
    if (success == false) {
        std::cout << cert.lastErrorText() << "\r\n";
        return;
    }

    CkBinData bd;
    success = bd.LoadFile("qa_data/openssl/hello.txt");
    // Assuming success..

    CkCrypt2 crypt;
    success = crypt.SetEncryptCert(cert);
    if (success == false) {
        std::cout << crypt.lastErrorText() << "\r\n";
        return;
    }

    crypt.put_CryptAlgorithm("PKI");

    // Indicate the underlying symmetric encryption to be used:
    crypt.put_Pkcs7CryptAlg("aes");
    crypt.put_KeyLength(256);
    crypt.put_CipherMode("cbc");

    success = crypt.CkEncryptFile("qa_data/openssl/hello.txt","qa_output/hello.txt.enc");
    if (success == false) {
        std::cout << crypt.lastErrorText() << "\r\n";
        return;
    }

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