Sample code for 30+ languages & platforms
C

Send Encrypted Email to Multiple Recipients

Demonstrates how to create and send an S/MIME encrypted email to multiple recipients. The digital certificate of each recipient is required. The encrypting/sending process uses each recipient's digital certificate (which internally contains the public key). Each recipient decrypts the received email using his/her private key.

Chilkat C Downloads

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

void ChilkatSample(void)
    {
    BOOL success;
    HCkMailMan mailman;
    HCkCert cert1;
    HCkCert cert2;
    HCkCert cert3;
    HCkEmail email;

    success = FALSE;

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

    // The mailman object is used for sending and receiving email.
    mailman = CkMailMan_Create();

    // Set the SMTP server.
    CkMailMan_putSmtpHost(mailman,"smtp.mymailserver.com");

    // Load each recipient's certificate into a Chilkat certificate object.
    // This example loads the certificates from files.  However, the Chilkat
    // certificate object provides other means for loading certificates,
    // such as from in-memory PEM strings, or in-memory binary DER encoded form, etc.
    cert1 = CkCert_Create();
    success = CkCert_LoadFromFile(cert1,"recipient1.cer");
    if (success != TRUE) {
        printf("%s\n",CkCert_lastErrorText(cert1));
        CkMailMan_Dispose(mailman);
        CkCert_Dispose(cert1);
        return;
    }

    cert2 = CkCert_Create();
    success = CkCert_LoadFromFile(cert2,"recipient2.cer");
    if (success != TRUE) {
        printf("%s\n",CkCert_lastErrorText(cert2));
        CkMailMan_Dispose(mailman);
        CkCert_Dispose(cert1);
        CkCert_Dispose(cert2);
        return;
    }

    cert3 = CkCert_Create();
    success = CkCert_LoadFromFile(cert3,"recipient3.cer");
    if (success != TRUE) {
        printf("%s\n",CkCert_lastErrorText(cert3));
        CkMailMan_Dispose(mailman);
        CkCert_Dispose(cert1);
        CkCert_Dispose(cert2);
        CkCert_Dispose(cert3);
        return;
    }

    // Create a new email object
    email = CkEmail_Create();

    CkEmail_putSubject(email,"This email is encrypted and sent to 3 recipients");
    CkEmail_putBody(email,"This is an S/MIME encrypted mail sent to 3 recipients");
    CkEmail_putFrom(email,"Chilkat Support <support@chilkatsoft.com>");

    // Make each of the certificates available for encrypting the email
    // by calling AddEncryptCert for each.
    success = CkEmail_AddEncryptCert(email,cert1);
    if (success == TRUE) {
        success = CkEmail_AddEncryptCert(email,cert2);
    }

    if (success == TRUE) {
        success = CkEmail_AddEncryptCert(email,cert3);
    }

    if (success != TRUE) {
        printf("%s\n",CkEmail_lastErrorText(email));
        CkMailMan_Dispose(mailman);
        CkCert_Dispose(cert1);
        CkCert_Dispose(cert2);
        CkCert_Dispose(cert3);
        CkEmail_Dispose(email);
        return;
    }

    // Add 3 recipients to the email (2 TO addresses, and 1 CC address)
    success = CkEmail_AddTo(email,"Recipient 1","admin@cknotes.com");
    success = CkEmail_AddTo(email,"Recipient 2","somebody001122@yahoo.com");
    success = CkEmail_AddCC(email,"Recipient 3","somebody123xyz@gmail.com");

    // Indicate that the email is to be sent encrypted.
    CkEmail_putSendEncrypted(email,TRUE);

    // Send the encrypted email...
    success = CkMailMan_SendEmail(mailman,email);
    if (success != TRUE) {
        printf("%s\n",CkMailMan_lastErrorText(mailman));
    }
    else {
        printf("Encrypted Email Sent!\n");
    }



    CkMailMan_Dispose(mailman);
    CkCert_Dispose(cert1);
    CkCert_Dispose(cert2);
    CkCert_Dispose(cert3);
    CkEmail_Dispose(email);

    }