(C) IMAP SSH Tunneling (Port Forwarding)

Demonstrates how to setup and use an SSH tunnel for IMAP.

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#include <C_CkImap.h>
#include <C_CkEmail.h>

void ChilkatSample(void)
    {
    HCkImap imap;
    const char *sshHostname;
    int sshPort;
    BOOL success;
    int msgCount;
    int upperBound;
    int i;
    BOOL bUid;
    HCkEmail email;

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

    imap = CkImap_Create();

    // 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).
    sshHostname = "www.mysshserver.com";
    sshPort = 22;

    // Connect to an SSH server and establish the SSH tunnel:
    success = CkImap_SshOpenTunnel(imap,sshHostname,sshPort);
    if (success != TRUE) {
        printf("%s\n",CkImap_lastErrorText(imap));
        CkImap_Dispose(imap);
        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 IMAP server, it is
    // for authenticating with the SSH server, which is separate.
    success = CkImap_SshAuthenticatePw(imap,"mySshLogin","mySshPassword");
    if (success != TRUE) {
        printf("%s\n",CkImap_lastErrorText(imap));
        CkImap_Dispose(imap);
        return;
    }

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

    // Connect to an IMAP server via the SSH tunnel.
    // Because the SSH tunnel has been previously setup,
    // this does not establish a direct connection with the IMAP
    // server.  It directs the SSH server to establish the connection.

    // In this example, the IMAP server requires SSL/TLS.  The TLS connection
    // will be enclosed within the SSH tunnel.
    CkImap_putSsl(imap,TRUE);
    CkImap_putPort(imap,993);
    success = CkImap_Connect(imap,"imap.my-imap-server.com");
    if (success != TRUE) {
        printf("%s\n",CkImap_lastErrorText(imap));
        CkImap_Dispose(imap);
        return;
    }

    // Authenticate with the IMAP server via the SSH tunnel.
    success = CkImap_Login(imap,"myLogin","myPassword");
    if (success != TRUE) {
        printf("%s\n",CkImap_lastErrorText(imap));
        CkImap_Dispose(imap);
        return;
    }

    // Select an IMAP mailbox
    success = CkImap_SelectMailbox(imap,"Inbox");
    if (success != TRUE) {
        printf("%s\n",CkImap_lastErrorText(imap));
        CkImap_Dispose(imap);
        return;
    }

    // How many messages in Inbox?
    msgCount = CkImap_getNumMessages(imap);
    if (msgCount == 0) {
        printf("No messages found.\n");
        CkImap_Dispose(imap);
        return;
    }

    upperBound = 10;
    if (msgCount < upperBound) {
        upperBound = msgCount;
    }

    // Download up to the 1st 10 messages.

    bUid = FALSE;
    for (i = 1; i <= upperBound; i++) {

        email = CkImap_FetchSingle(imap,i,bUid);
        if (CkImap_getLastMethodSuccess(imap) == FALSE) {
            printf("%s\n",CkImap_lastErrorText(imap));
            CkImap_Dispose(imap);
            return;

        }
        else {
            printf("%s\n",CkEmail_ck_from(email));
            printf("%s\n",CkEmail_subject(email));
            printf("----\n");

            CkEmail_Dispose(email);
        }

    }

    // Disconnect from the IMAP server.
    // The SSH tunnel remains open.
    success = CkImap_Disconnect(imap);
    if (success != TRUE) {
        printf("%s\n",CkImap_lastErrorText(imap));
        CkImap_Dispose(imap);
        return;
    }

    // It is possible to re-use the existing SSH tunnel for the next connection:
    success = CkImap_Connect(imap,"imap.my-imap-server2.com");
    if (success != TRUE) {
        printf("%s\n",CkImap_lastErrorText(imap));
        CkImap_Dispose(imap);
        return;
    }

    // Review the LastErrorText to see that the connection was made via the SSH tunnel:
    printf("%s\n",CkImap_lastErrorText(imap));

    success = CkImap_Disconnect(imap);
    if (success != TRUE) {
        printf("%s\n",CkImap_lastErrorText(imap));
        CkImap_Dispose(imap);
        return;
    }

    // Finally, close the SSH tunnel.
    success = CkImap_SshCloseTunnel(imap);
    if (success != TRUE) {
        printf("%s\n",CkImap_lastErrorText(imap));
        CkImap_Dispose(imap);
        return;
    }

    printf("IMAP SSH tunneling example completed.\n");


    CkImap_Dispose(imap);

    }