C++

Upgrade an FTP Control Channel to TLS (ConvertToTls)

Demonstrates the Chilkat Ftp2.ConvertToTls method, which upgrades an already-connected clear FTP control channel to explicit TLS. It takes no arguments and is used with a manually staged connection created by ConnectOnly while Ssl is disabled.

Background: This exposes the explicit-FTPS AUTH TLS upgrade as a discrete step for the rare case where you need to do something on the clear connection first — inspect the greeting, apply a workaround — before securing it. In the normal case you simply set AuthTls and let Connect perform the upgrade automatically; this manual path exists for staged control.

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C++

#include <CkFtp2.h>

void ChilkatSample(void)
    {
    bool success = false;

    //  Demonstrates the Ftp2.ConvertToTls method, which upgrades an already-connected clear FTP control
    //  channel to explicit TLS.  It takes no arguments.  It is used with a manually staged connection
    //  created by ConnectOnly while Ssl is disabled.

    CkFtp2 ftp;

    ftp.put_Hostname("ftp.example.com");
    ftp.put_Port(21);

    //  Connect in clear text first (Ssl is false).
    success = ftp.ConnectOnly();
    if (success == false) {
        std::cout << ftp.lastErrorText() << "\r\n";
        return;
    }

    //  Upgrade the control channel to explicit TLS (AUTH TLS).
    success = ftp.ConvertToTls();
    if (success == false) {
        std::cout << ftp.lastErrorText() << "\r\n";
        return;
    }

    //  Now authenticate over the encrypted control channel.
    ftp.put_Username("myFtpLogin");
    ftp.put_Password("myPassword");
    success = ftp.LoginAfterConnectOnly();
    if (success == false) {
        std::cout << ftp.lastErrorText() << "\r\n";
        return;
    }

    std::cout << "Control channel upgraded to TLS and logged in." << "\r\n";

    success = ftp.Disconnect();
    if (success == false) {
        std::cout << ftp.lastErrorText() << "\r\n";
        return;
    }
    }