Start SSH Tunnel Keyboard-Interactive Authentication

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Demonstrates the Chilkat SshTunnel.StartKeyboardAuth method, which begins keyboard-interactive authentication. The only argument is the login name. It returns XML describing the server's prompts, which are answered with ContinueKeyboardAuth.

Background: Keyboard-interactive is the prompt-driven authentication method: the server sends one or more questions — a password, a one-time code, a security question — and the client answers each. This is how a tunnel supports two-factor and other challenge-response schemes. The returned XML says exactly what to ask and whether to mask the input.

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#include <C_CkSshTunnel.h>

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

    success = FALSE;

    //  Demonstrates the SshTunnel.StartKeyboardAuth method, which begins keyboard-interactive
    //  authentication.  The only argument is the login name.  It returns XML describing the server's
    //  prompts, which are answered with ContinueKeyboardAuth.

    tunnel = CkSshTunnel_Create();

    //  The tunnel forwards accepted local connections to this destination through the SSH server.
    CkSshTunnel_putDestHostname(tunnel,"db.internal.example.com");
    CkSshTunnel_putDestPort(tunnel,5432);

    //  Connect to the SSH server.  This performs the TCP/proxy connection and SSH handshake, but
    //  does not authenticate yet.
    sshPort = 22;
    success = CkSshTunnel_Connect(tunnel,"ssh.example.com",sshPort);
    if (success == FALSE) {
        printf("%s\n",CkSshTunnel_lastErrorText(tunnel));
        CkSshTunnel_Dispose(tunnel);
        return;
    }

    //  Begin keyboard-interactive authentication.  The returned XML describes the server's prompts.
    infoRequestXml = CkSshTunnel_startKeyboardAuth(tunnel,"mySshLogin");
    if (CkSshTunnel_getLastMethodSuccess(tunnel) == FALSE) {
        printf("%s\n",CkSshTunnel_lastErrorText(tunnel));
        CkSshTunnel_Dispose(tunnel);
        return;
    }

    printf("%s\n",infoRequestXml);

    //  Answer the prompt(s) with ContinueKeyboardAuth, then call BeginAccepting.

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



    CkSshTunnel_Dispose(tunnel);

    }