(C) S/MIME Encrypt .eml without Sending

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#include <C_CkEmail.h>
#include <C_CkCert.h>
#include <C_CkStringBuilder.h>
#include <C_CkMailMan.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkEmail email;
    HCkCert cert;
    HCkStringBuilder sbSmime;
    HCkMailMan mailman;

    success = FALSE;

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

    email = CkEmail_Create();

    success = CkEmail_LoadEml(email,"c:/temp/email/unencrypted.eml");
    if (success == FALSE) {
        printf("%s\n",CkEmail_lastErrorText(email));
        CkEmail_Dispose(email);
        return;
    }

    // The email content is encrypted using AES with a 256-bit key, operating in GCM mode, which provides authenticated encryption.
    CkEmail_putPkcs7CryptAlg(email,"aes-gcm");
    CkEmail_putPkcs7KeyLength(email,256);
    CkEmail_putOaepPadding(email,TRUE);
    CkEmail_putOaepHash(email,"sha256");
    CkEmail_putOaepMgfHash(email,"sha256");

    cert = CkCert_Create();
    success = CkCert_LoadFromFile(cert,"c/temps/cert/recipient.cer");
    if (success == FALSE) {
        printf("%s\n",CkCert_lastErrorText(cert));
        CkEmail_Dispose(email);
        CkCert_Dispose(cert);
        return;
    }

    CkEmail_putSendEncrypted(email,TRUE);
    CkEmail_SetEncryptCert(email,cert);

    sbSmime = CkStringBuilder_Create();

    // The mailman object applies the encryption by rendering the email according to the instructions (property settings) provided in the email object.
    // No email is sent.
    mailman = CkMailMan_Create();
    success = CkMailMan_RenderToMimeSb(mailman,email,sbSmime);
    if (success == FALSE) {
        printf("%s\n",CkMailMan_lastErrorText(mailman));
        CkEmail_Dispose(email);
        CkCert_Dispose(cert);
        CkStringBuilder_Dispose(sbSmime);
        CkMailMan_Dispose(mailman);
        return;
    }

    success = CkStringBuilder_WriteFile(sbSmime,"c:/temp/encryptedEmail.eml","utf-8",FALSE);
    if (success == FALSE) {
        printf("%s\n",CkMailMan_lastErrorText(mailman));
        CkEmail_Dispose(email);
        CkCert_Dispose(cert);
        CkStringBuilder_Dispose(sbSmime);
        CkMailMan_Dispose(mailman);
        return;
    }

    printf("Success!\n");


    CkEmail_Dispose(email);
    CkCert_Dispose(cert);
    CkStringBuilder_Dispose(sbSmime);
    CkMailMan_Dispose(mailman);

    }