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Unicode C++

POP3 SSH Tunneling (Port Forwarding)

Demonstrates how to connect to a POP3 server through an SSH tunnel. Reads a POP3 mailbox and display the FROM and SUBJECT header fields of each email.

Chilkat Unicode C++ Downloads

Unicode C++
#include <CkMailManW.h>
#include <CkEmailW.h>

void ChilkatSample(void)
    {
    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 receiving (POP3) 
    //  and sending (SMTP) email.
    CkMailManW mailman;

    //  The SSH hostname may be a hostname or an 
    //  IP address, such as "192.168.1.108".
    //  The port is typically 22 (the standard port for SSH).
    const wchar_t *sshHostname = L"sftp.example.com";
    int sshPort = 22;

    //  Connect to an SSH server and establish the SSH tunnel:
    success = mailman.SshOpenTunnel(sshHostname,sshPort);
    if (success == false) {
        wprintf(L"%s\n",mailman.lastErrorText());
        return;
    }

    //  Authenticate with the SSH server via a login/password
    //  or with a public key.
    //  This example demonstrates SSH password authentication.
    //  Note: This is not authenticating with the POP3 server, it is
    //  for authenticating with the SSH server, which is separate.
    success = mailman.SshAuthenticatePw(L"ssh_login",L"ssh_password");
    if (success == false) {
        wprintf(L"%s\n",mailman.lastErrorText());
        return;
    }

    //  OK, the SSH tunnel is setup.  The mailman may
    //  be used exactly the same as usual, except all communications
    //  are now sent through the SSH tunnel.

    //  The SSH tunnel may be kept open for any number of 
    //  POP3 connections.  

    //  Set the POP3 server's hostname
    mailman.put_MailHost(L"mail.my-pop3-server.com");

    //  Set the POP3 settings for your POP3 server:
    mailman.put_PopUsername(L"pop3_login");
    mailman.put_PopPassword(L"pop3_password");
    mailman.put_MailPort(995);
    mailman.put_PopSsl(true);

    //  Connect to the POP3 server through the already-established SSH tunnel:
    success = mailman.Pop3BeginSession();
    if (success == false) {
        wprintf(L"%s\n",mailman.lastErrorText());
        return;
    }

    //  A visual inspection of the LastErrorText after
    //  a successful POP3 connection will confirm the SSH tunneling.
    //  Note: If the POP3 connection uses SSL/TLS, then the SSL/TLS 
    //  secure channel will be wrapped within the SSH tunnel.
    wprintf(L"%s\n",mailman.lastErrorText());

    //  How many messages are in the POP3 inbox?
    int numToDownload = mailman.GetMailboxCount();
    if (numToDownload > 5) {
        numToDownload = 5;
    }

    if (numToDownload == 0) {
        wprintf(L"No messages in the POP3 inbox.\n");
        return;
    }

    //  Download a max of 5 messages
    int i;
    CkEmailW email;
    for (i = 1; i <= numToDownload; i++) {
        success = mailman.FetchOne(false,0,i,email);
        if (success == false) {
            wprintf(L"%s\n",mailman.lastErrorText());
            return;
        }

        wprintf(L"%s\n",email.ck_from());
        wprintf(L"%s\n",email.subject());
        wprintf(L"----\n");
    }

    //  Close the connection with the POP3 server, leaving the SSH tunnel open for subsequent POP3 connections.
    success = mailman.Pop3EndSession();
    if (success == false) {
        wprintf(L"%s\n",mailman.lastErrorText());
        return;
    }

    //  Try connecting to a different POP3 server through the same aleady setup SSH tunnel:
    //  Set the POP3 server's hostname
    mailman.put_MailHost(L"mail.my-pop3-server2.com");

    //  Set the POP3 settings for your POP3 server:
    mailman.put_PopUsername(L"pop3_login2");
    mailman.put_PopPassword(L"pop3_password2");
    mailman.put_MailPort(110);
    mailman.put_PopSsl(false);

    success = mailman.Pop3BeginSession();
    if (success == false) {
        wprintf(L"%s\n",mailman.lastErrorText());
        return;
    }

    //  Review the LastErrorText to see that the connection was made via the SSH tunnel:
    wprintf(L"%s\n",mailman.lastErrorText());

    success = mailman.Pop3EndSession();
    if (success == false) {
        wprintf(L"%s\n",mailman.lastErrorText());
        return;
    }

    //  Close the SSH tunnel.
    success = mailman.SshCloseTunnel();
    if (success == false) {
        wprintf(L"%s\n",mailman.lastErrorText());
        return;
    }
    }