(Unicode C) Duplicate openssl smime -decrypt -in some_file.dat.enc -binary -inform DER -inkey private.key -out some_file.dat

Demonstrates how to decrypt binary DER that was encrypted using 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/C++ Library Downloads
MS Visual C/C++ Linux/CentOS C/C++ Alpine Linux C/C++ MAC OS X C/C++	armhf/aarch64 C/C++ C++ Builder iOS C/C++ Android C/C++	Solaris C/C++ MinGW C/C++

#include <C_CkCertW.h>
#include <C_CkBinDataW.h>
#include <C_CkPrivateKeyW.h>
#include <C_CkCrypt2W.h>

void ChilkatSample(void)
    {
    HCkCertW cert;
    BOOL success;
    HCkBinDataW bd;
    HCkPrivateKeyW privKey;
    HCkCrypt2W crypt;

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

    // Duplicates the following openssl command:
    // openssl smime -decrypt -in hello.txt.enc -binary -inform DER -inkey private.key -out hello.txt

    cert = CkCertW_Create();
    success = CkCertW_LoadFromFile(cert,L"qa_data/openssl/EE.cer");
    if (success == FALSE) {
        wprintf(L"%s\n",CkCertW_lastErrorText(cert));
        CkCertW_Dispose(cert);
        return;
    }

    bd = CkBinDataW_Create();
    success = CkBinDataW_LoadFile(bd,L"qa_data/openssl/EE.key");
    // Assuming success..

    privKey = CkPrivateKeyW_Create();
    success = CkPrivateKeyW_LoadAnyFormat(privKey,bd,L"");
    if (success == FALSE) {
        wprintf(L"%s\n",CkPrivateKeyW_lastErrorText(privKey));
        CkCertW_Dispose(cert);
        CkBinDataW_Dispose(bd);
        CkPrivateKeyW_Dispose(privKey);
        return;
    }

    crypt = CkCrypt2W_Create();
    success = CkCrypt2W_SetDecryptCert2(crypt,cert,privKey);
    if (success == FALSE) {
        wprintf(L"%s\n",CkCrypt2W_lastErrorText(crypt));
        CkCertW_Dispose(cert);
        CkBinDataW_Dispose(bd);
        CkPrivateKeyW_Dispose(privKey);
        CkCrypt2W_Dispose(crypt);
        return;
    }

    CkCrypt2W_putCryptAlgorithm(crypt,L"PKI");
    success = CkCrypt2W_CkDecryptFile(crypt,L"qa_data/openssl/hello.txt.enc",L"qa_output/hello.txt");
    if (success == FALSE) {
        wprintf(L"%s\n",CkCrypt2W_lastErrorText(crypt));
        CkCertW_Dispose(cert);
        CkBinDataW_Dispose(bd);
        CkPrivateKeyW_Dispose(privKey);
        CkCrypt2W_Dispose(crypt);
        return;
    }

    wprintf(L"Success.\n");


    CkCertW_Dispose(cert);
    CkBinDataW_Dispose(bd);
    CkPrivateKeyW_Dispose(privKey);
    CkCrypt2W_Dispose(crypt);

    }