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PHP Extension

Send Signed Email using PFX File (long version)

Demonstrates how to send a signed email using a digital certificate w/ private key stored in a PFX file.

Chilkat PHP Extension Downloads

PHP Extension
<?php

include("chilkat.php");

$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 = new CkMailMan();

// Set the SMTP server.
$mailman->put_SmtpHost('smtp.mymailserver.com');

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

$email->put_Subject('This email is signed');
$email->put_Body('This is a digitally signed mail');
$email->put_From('Chilkat Admin <admin@chilkatsoft.com>');
$success = $email->AddTo('Chilkat Support','support@chilkatsoft.com');

// Indicate that the email should be sent signed.
$email->put_SendSigned(true);

// Load a PFX file into a certificate store object.
// Then locate the certificate matching the  sender's email address,
// and use it for signing.
// (a PFX file may contain more than one certificate.)
$certStore = new CkCertStore();
// The 1st argument is the path of the PFX file, the 2nd arg is the 
// PFX file's password:
$success = $certStore->LoadPfxFile('/pfx_files/chilkatsoft_secret.pfx','secret');
if ($success != true) {
    print $certStore->lastErrorText() . "\n";
    exit;
}

// Find the certificate for the email address:
$jsonE = new CkJsonObject();
$jsonE->UpdateString('email','admin@chilkatsoft.com');

$cert = new CkCert();
$success = $certStore->FindCert($jsonE,$cert);
if ($success == false) {
    print $certStore->lastErrorText() . "\n";
    exit;
}

// Alternatively, if a PFX file is known to contain a single certificate,
// you may load it directly into a Chilkat certificate object.
// This snippet of source code shows how:
$cert2 = new CkCert();
// The 1st argument is the filename, the 2nd arg is the 
// PFX file's password:
$success = $cert2->LoadPfxFile('/pfx_files/chilkatsoft_secret.pfx','secret');
if ($success != true) {
    print $cert2->lastErrorText() . "\n";
    exit;
}

// This example will use the cert from the certStore...
$success = $email->SetSigningCert($cert);

// Signed email can be sent in two different ways.  
// In a multipart/signed email, the signature is attached as a separate MIME part.
// In an opaque email (signedData) the content of the email is encapsulated within the signature
// and the email is sent as "application/pkcs7-mime". 
// Either should be fine, but some receiving systems might require one or the other..
$mailman->put_OpaqueSigning(false);

// Send a signed email.
$success = $mailman->SendEmail($email);
if ($success != true) {
    print $mailman->lastErrorText() . "\n";
}
else {
    // The LastErrorText property provides information
    // even when successful.
    print $mailman->lastErrorText() . "\n";
    print 'Mail Sent!' . "\n";
}


?>