(C++) Extract PKCS7 from MIME and Decrypt

Extracts the base64-encoded PKCS7 body of a MIME message to a file, and then decrypts using Chilkat Crypt2.

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#include <CkMime.h>
#include <CkCrypt2.h>

void ChilkatSample(void)
    {
    // This example assumes the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    CkMime mime;

    bool success = mime.LoadMimeFile("c:/aaworkarea/EmailInBytes.txt");
    if (success != true) {
        std::cout << mime.lastErrorText() << "\r\n";
        return;
    }

    success = mime.SaveBody("c:/aaworkarea/smime.p7m");
    if (success != true) {
        std::cout << mime.lastErrorText() << "\r\n";
        return;
    }

    CkCrypt2 crypt;

    success = crypt.AddPfxSourceFile("c:/aaworkarea/my.pfx","pfxPassword");
    if (success == false) {
        std::cout << crypt.lastErrorText() << "\r\n";
        return;
    }

    // Indicate the public-key (PKCS7) encryption/decryption should be used:
    crypt.put_CryptAlgorithm("pki");

    const char *inPath = "c:/aaworkarea/smime.p7m";
    const char *outPath = "c:/aaworkarea/decrypted.dat";

    success = crypt.CkDecryptFile(inPath,outPath);
    if (success == false) {
        std::cout << crypt.lastErrorText() << "\r\n";
        return;
    }

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