(PHP Extension) 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.

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<?php

// The version number (9_5_0) should match version of the Chilkat extension used, omitting the micro-version number.
// For example, if using Chilkat v9.5.0.48, then include as shown here:
include("chilkat_9_5_0.php");

// 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 = new CkMailMan();

// Set the SMTP server.
$mailman->put_SmtpHost('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 = new CkCert();
$success = $cert1->LoadFromFile('recipient1.cer');
if ($success != true) {
    print $cert1->lastErrorText() . "\n";
    exit;
}

$cert2 = new CkCert();
$success = $cert2->LoadFromFile('recipient2.cer');
if ($success != true) {
    print $cert2->lastErrorText() . "\n";
    exit;
}

$cert3 = new CkCert();
$success = $cert3->LoadFromFile('recipient3.cer');
if ($success != true) {
    print $cert3->lastErrorText() . "\n";
    exit;
}

// Create a new email object
$email = new CkEmail();

$email->put_Subject('This email is encrypted and sent to 3 recipients');
$email->put_Body('This is an S/MIME encrypted mail sent to 3 recipients');
$email->put_From('Chilkat Support <support@chilkatsoft.com>');

// Make each of the certificates available for encrypting the email
// by calling AddEncryptCert for each.
$success = $email->AddEncryptCert($cert1);
if ($success == true) {
    $success = $email->AddEncryptCert($cert2);
}

if ($success == true) {
    $success = $email->AddEncryptCert($cert3);
}

if ($success != true) {
    print $email->lastErrorText() . "\n";
    exit;
}

// Add 3 recipients to the email (2 TO addresses, and 1 CC address)
$success = $email->AddTo('Recipient 1','admin@cknotes.com');
$success = $email->AddTo('Recipient 2','somebody001122@yahoo.com');
$success = $email->AddCC('Recipient 3','somebody123xyz@gmail.com');

// Indicate that the email is to be sent encrypted.
$email->put_SendEncrypted(true);

// Send the encrypted email...
$success = $mailman->SendEmail($email);
if ($success != true) {
    print $mailman->lastErrorText() . "\n";
}
else {
    print 'Encrypted Email Sent!' . "\n";
}


?>