SSH Tunnel Per-Client Logging and Client Identifier

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Demonstrates the ClientLogDir and ClientIdentifier properties. When ClientLogDir is set, a separate log file is created for each tunnel client; ClientIdentifier is the SSH client-identification string sent during the handshake.

Note: The log paths are relative to the application's current working directory. Absolute paths may also be used.

Background: When many clients share one tunnel, a single combined log is hard to follow, so ClientLogDir gives each connection its own file — the fastest way to diagnose one misbehaving client. ClientIdentifier sets the version string the server sees; overriding the default is occasionally needed for compatibility with servers that key behavior off the client identification, or simply to label your application in server logs.

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#include <C_CkSshTunnel.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkSshTunnel tunnel;
    int sshPort;
    const char *password;
    int listenPort;
    BOOL waitForThreadExit;

    success = FALSE;

    //  Demonstrates the SshTunnel per-client logging properties ClientLogDir and ClientIdentifier.

    tunnel = CkSshTunnel_Create();

    //  When ClientLogDir is set, a separate log file is created for each tunnel client in this
    //  directory, which is useful for troubleshooting individual connections.
    CkSshTunnel_putClientLogDir(tunnel,"qa_output/client_logs");

    //  The SSH client-identification string sent to the SSH server during the handshake.
    CkSshTunnel_putClientIdentifier(tunnel,"SSH-2.0-MyTunnelApp_1.0");

    CkSshTunnel_putDestHostname(tunnel,"db.internal.example.com");
    CkSshTunnel_putDestPort(tunnel,5432);

    sshPort = 22;
    success = CkSshTunnel_Connect(tunnel,"ssh.example.com",sshPort);
    if (success == FALSE) {
        printf("%s\n",CkSshTunnel_lastErrorText(tunnel));
        CkSshTunnel_Dispose(tunnel);
        return;
    }

    //  Normally you would not hard-code the password in source.  You should instead obtain it
    //  from an interactive prompt, environment variable, or a secrets vault.
    password = "mySshPassword";

    success = CkSshTunnel_AuthenticatePw(tunnel,"mySshLogin",password);
    if (success == FALSE) {
        printf("%s\n",CkSshTunnel_lastErrorText(tunnel));
        CkSshTunnel_Dispose(tunnel);
        return;
    }

    listenPort = 1080;
    success = CkSshTunnel_BeginAccepting(tunnel,listenPort);
    if (success == FALSE) {
        printf("%s\n",CkSshTunnel_lastErrorText(tunnel));
        CkSshTunnel_Dispose(tunnel);
        return;
    }

    printf("Tunnel running; each client is logged in %s\n",CkSshTunnel_clientLogDir(tunnel));

    waitForThreadExit = TRUE;
    success = CkSshTunnel_CloseTunnel(tunnel,waitForThreadExit);
    if (success == FALSE) {
        printf("%s\n",CkSshTunnel_lastErrorText(tunnel));
        CkSshTunnel_Dispose(tunnel);
        return;
    }



    CkSshTunnel_Dispose(tunnel);

    }