Use an Existing Socket SSH Tunnel

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Demonstrates the Chilkat MailMan.UseSshTunnel method, which configures MailMan to use an existing SSH tunnel provided by a Socket object for its SMTP and POP3 connections. This example opens and authenticates a tunnel on a Socket, hands it to MailMan, and then verifies an SMTP login through it.

Background: Sharing one already-established SSH tunnel across objects avoids opening (and authenticating) a separate SSH connection for every component that needs to reach the remote network. Here the tunnel lives on a Socket object, which MailMan then routes its SMTP/POP3 traffic through. It is the Socket-based sibling of UseSsh, which shares an Ssh object instead.

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#include <C_CkSocket.h>
#include <C_CkMailMan.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkSocket sshTunnel;
    HCkMailMan mailman;

    success = FALSE;

    //  Demonstrates the MailMan.UseSshTunnel method, which configures MailMan to use an existing
    //  SSH tunnel provided by a Socket object for its SMTP and POP3 connections.

    //  Open and authenticate the SSH tunnel using a Socket object.
    sshTunnel = CkSocket_Create();
    success = CkSocket_SshOpenTunnel(sshTunnel,"ssh.example.com",22);
    if (success == FALSE) {
        printf("%s\n",CkSocket_lastErrorText(sshTunnel));
        CkSocket_Dispose(sshTunnel);
        return;
    }

    success = CkSocket_SshAuthenticatePw(sshTunnel,"sshUser","sshPassword");
    if (success == FALSE) {
        printf("%s\n",CkSocket_lastErrorText(sshTunnel));
        CkSocket_Dispose(sshTunnel);
        return;
    }

    mailman = CkMailMan_Create();

    //  Configure the SMTP server connection.  These connections will travel through the tunnel.
    CkMailMan_putSmtpHost(mailman,"smtp.example.com");
    CkMailMan_putSmtpPort(mailman,465);
    CkMailMan_putSmtpSsl(mailman,TRUE);
    CkMailMan_putSmtpUsername(mailman,"user@example.com");
    CkMailMan_putSmtpPassword(mailman,"myPassword");

    //  Tell MailMan to route its connections through the existing tunnel.
    success = CkMailMan_UseSshTunnel(mailman,sshTunnel);
    if (success == FALSE) {
        printf("%s\n",CkMailMan_lastErrorText(mailman));
        CkSocket_Dispose(sshTunnel);
        CkMailMan_Dispose(mailman);
        return;
    }

    //  SMTP operations now travel through the shared SSH tunnel.
    success = CkMailMan_VerifySmtpLogin(mailman);
    if (success == FALSE) {
        printf("%s\n",CkMailMan_lastErrorText(mailman));
        CkSocket_Dispose(sshTunnel);
        CkMailMan_Dispose(mailman);
        return;
    }

    printf("Authenticated with the SMTP server through the SSH tunnel.\n");


    CkSocket_Dispose(sshTunnel);
    CkMailMan_Dispose(mailman);

    }