.NET Core C#

POP3 Read S/MIME Encrypted Email

Read S/MIME encrypted email. .NET Core C#

bool success = false;

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

// The mailman object is used for receiving (POP3) 
// and sending (SMTP) email.
Chilkat.MailMan mailman = new Chilkat.MailMan();

// Set the POP3 server's hostname
mailman.MailHost = "pop.example.com";

// Set the POP3 login/password.
mailman.PopUsername = "myLogin";
mailman.PopPassword = "myPassword";

// If running on Microsoft Windows, the Chilkat mailman
// will automatically search the registry-based certificate stores
// for matching certificates and private keys required for
// decryption.  However, on Linux, MAX OS X, and other
// operating systems, no such thing exists.  Therefore, you'll 
// need to specify one or more PFX (.p12 / .pfx) files as
// sources for locating the certs required for decyrption.
success = mailman.AddPfxSourceFile("/pfxFiles/certs_and_keys_1.pfx","pfxPassword1");
if (success == false) {
    Debug.WriteLine(mailman.LastErrorText);
    return;
}

success = mailman.AddPfxSourceFile("/pfxFiles/certs_and_keys_2.pfx","pfxPassword2");
if (success == false) {
    Debug.WriteLine(mailman.LastErrorText);
    return;
}

// ...
// Note: On MS Windows, it is not required to provide PFX sources
// if the needed certs and private keys are already installed
// on the system (in the registry-based certificate stores).

// Copy the all email from the user's POP3 mailbox 
// into a bundle object.  The email remains on the server.
Chilkat.EmailBundle bundle = new Chilkat.EmailBundle();
bool keepOnServer = true;
bool headersOnly = false;
// Irrelevent because we are NOT downloading headers-only
int numBodyLines = 0;
success = mailman.FetchAll(keepOnServer,headersOnly,numBodyLines,bundle);
if (success == false) {
    Debug.WriteLine(mailman.LastErrorText);
    return;
}

// S/MIME security envelopes are automatically "unwrapped" 
// when a message is retrieved from the server. Signed emails are automatically verified, and 
// encrypted emails are automatically decrypted, restoring the email to the original state before 
// signing and/or encrypting. Information about the signing and encrypting certificates can be 
// retrieved from the Email object (methods: GetSignedByCert, GetEncryptedByCert; 
// properties: SignedBy, EncryptedBy, SignaturesValid, Decrypted, ReceivedSigned, 
// ReceivedEncrypted).

// Loop over the bundle
Chilkat.Email email = new Chilkat.Email();
int i = 0;
while (i < bundle.MessageCount) {

    bundle.EmailAt(i,email);

    Debug.WriteLine(email.From);
    Debug.WriteLine(email.Subject);

    // At this point, if the email was signed and/or encrypted, it is already "unwrapped", i.e.
    // the email is already decrypted and in a state as if it were never signed or encrypted.
    // You may check to see if the email was received encrypted or signed, and if so,
    // whether it was successfully unwrapped and who signed or encrypted it:
    if (email.ReceivedEncrypted == true) {

        Debug.WriteLine("This email was encrypted when received.");
        if (email.Decrypted == true) {
            Debug.WriteLine("This email was successfully decrypted.  It was encrypted by:");
            Debug.WriteLine(email.EncryptedBy);
        }
        else {
            Debug.WriteLine("This email was not decrypted.");
        }

    }

    if (email.ReceivedSigned == true) {

        Debug.WriteLine("This email was signed when received.");
        if (email.SignaturesValid == true) {
            Debug.WriteLine("The signature was verified.  It was signed by:");
            Debug.WriteLine(email.SignedBy);
        }
        else {
            Debug.WriteLine("The signature verification failed.");
        }

    }

    // The email's body, HTML body, attachments, etc.
    // are decrypted and available just like any non-encrypted email.

    Debug.WriteLine("--");

    i = i + 1;
}