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JavaScript

S/MIME Encrypt .eml without Sending

See more Email Object Examples

Demonstrates how to encrypt an email using the recipient's digital certificate. This example just encrypts, and does not send the email.
Note
This example is intended for running within a Chilkat.Js embedded JavaScript engine. All Chilkat JavaScript examples require Chilkat v11.4.0 or greater.
JavaScript
var success = false;

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

var email = new CkEmail();

success = email.LoadEml("c:/temp/email/unencrypted.eml");
if (success == false) {
    console.log(email.LastErrorText);
    return;
}

// The email content is encrypted using AES with a 256-bit key, operating in GCM mode, which provides authenticated encryption.
email.Pkcs7CryptAlg = "aes-gcm";
email.Pkcs7KeyLength = 256;
email.OaepPadding = true;
email.OaepHash = "sha256";
email.OaepMgfHash = "sha256";

var cert = new CkCert();
success = cert.LoadFromFile("c/temps/cert/recipient.cer");
if (success == false) {
    console.log(cert.LastErrorText);
    return;
}

email.SendEncrypted = true;
email.SetEncryptCert(cert);

var sbSmime = new CkStringBuilder();

// 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.
var mailman = new CkMailMan();
success = mailman.RenderToMimeSb(email,sbSmime);
if (success == false) {
    console.log(mailman.LastErrorText);
    return;
}

success = sbSmime.WriteFile("c:/temp/encryptedEmail.eml","utf-8",false);
if (success == false) {
    console.log(mailman.LastErrorText);
    return;
}

console.log("Success!");