C#

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. C#

bool 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.
Chilkat.MailMan mailman = new Chilkat.MailMan();

//  Set the SMTP server.
mailman.SmtpHost = "smtp.mymailserver.com";

//  Create a new email object
Chilkat.Email email = new Chilkat.Email();

email.Subject = "This email is signed";
email.Body = "This is a digitally signed mail";
email.From = "Chilkat Admin <admin@chilkatsoft.com>";
success = email.AddTo("Chilkat Support","support@chilkatsoft.com");

//  Indicate that the email should be sent signed.
email.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.)
Chilkat.CertStore certStore = new Chilkat.CertStore();
//  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) {
    Debug.WriteLine(certStore.LastErrorText);
    return;
}

//  Find the certificate for the email address:
Chilkat.JsonObject jsonE = new Chilkat.JsonObject();
jsonE.UpdateString("email","admin@chilkatsoft.com");

Chilkat.Cert cert = new Chilkat.Cert();
success = certStore.FindCert(jsonE,cert);
if (success == false) {
    Debug.WriteLine(certStore.LastErrorText);
    return;
}

//  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:
Chilkat.Cert cert2 = new Chilkat.Cert();
//  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) {
    Debug.WriteLine(cert2.LastErrorText);
    return;
}

//  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.OpaqueSigning = false;

//  Send a signed email.
success = mailman.SendEmail(email);
if (success != true) {
    Debug.WriteLine(mailman.LastErrorText);
}
else {
    //  The LastErrorText property provides information
    //  even when successful.
    Debug.WriteLine(mailman.LastErrorText);
    Debug.WriteLine("Mail Sent!");
}