C++

SSH Tunnel Authenticate with a SecureString Password

Demonstrates the Chilkat SshTunnel.AuthenticateSecPw method, which authenticates using SecureString login and password objects. The first argument is the login and the second is the password.

Background: Because a tunnel process is long-lived and holds its SSH credentials for its entire lifetime, protecting them in memory is worthwhile. A SecureString keeps the value encrypted under a randomly generated session key. Populate it from a value obtained at runtime rather than a hard-coded literal.

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#include <CkSshTunnel.h>
#include <CkSecureString.h>

void ChilkatSample(void)
    {
    bool success = false;

    //  Demonstrates the SshTunnel.AuthenticateSecPw method, which authenticates using SecureString
    //  login and password objects.  The 1st argument is the login and the 2nd is the password.

    CkSshTunnel tunnel;

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

    //  Connect to the SSH server.  This performs the TCP/proxy connection and SSH handshake, but
    //  does not authenticate yet.
    int sshPort = 22;
    success = tunnel.Connect("ssh.example.com",sshPort);
    if (success == false) {
        std::cout << tunnel.lastErrorText() << "\r\n";
        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.
    const char *password = "mySshPassword";

    //  Place the login and password into SecureString objects.
    CkSecureString secureLogin;
    secureLogin.Append("mySshLogin");
    CkSecureString securePassword;
    securePassword.Append(password);

    success = tunnel.AuthenticateSecPw(secureLogin,securePassword);
    if (success == false) {
        std::cout << tunnel.lastErrorText() << "\r\n";
        return;
    }

    std::cout << "Authenticated with secure strings." << "\r\n";

    //  After authenticating, call BeginAccepting to start listening for local connections to forward.

    bool waitForThreadExit = true;
    success = tunnel.CloseTunnel(waitForThreadExit);
    if (success == false) {
        std::cout << tunnel.lastErrorText() << "\r\n";
        return;
    }
    }