Re: [Ncat] hang on ongoing ssl negotation in brokering mode

[David Fifield <david () bamsoftware com>]

On Mon, Jun 13, 2011 at 09:24:27PM +0300, Shinnok wrote:
> On 06/13/2011 06:56 PM, Shinnok wrote:
> > On 06/11/2011 09:33 PM, David Fifield wrote:
> > > This patch looks very nice, Shinnok. Please change the name "ssldone" to
> > > something more descriptive; it doesn't mean "SSL done," it means "SSL
> > > accept done."
> > Renamed to ssl_accept_done. Commited.
> > > I don't think the patch works when the server runs --sh-exec. For
> > > example
> > >    ncat --ssl --sh-exec "date" -lk
> > > Connecting with a non-SSL client prevents SSL clients from receiving any
> > > data. I added a new test for this case. Would you look into it?
> > Indeed it doesn't work with --exec modes, since they take a different
> > path in code. Fixed for that path too in r23946.
>
> Argh, and there's ncat_exec_win.c that I have to handle too, if I'm not
> mistaken, since I only too cake of the netexec() in ncat_posix.c? Any
> special comments for that David? I see there's some playing around with
> blocking/unblocking of the remote socket(@420) which might interfere
> with making this work.

Yes, it should work for Windows too. You probably don't have to worry
about that blocking detail.

Please find a way to factor this code into its own function. It's too
much to have it repeated in each read loop.

            if(o.ssl && info->ssl && !info->ssl_accept_done){
                int ret = SSL_accept(info->ssl);
                int sslerr = 0;
                if(ret == 1){
                    info->ssl_accept_done = 1;
                    continue;
                }else
                sslerr = SSL_get_error(info->ssl, ret);
                if(ret == -1 && (sslerr == SSL_ERROR_WANT_READ
                                 || sslerr == SSL_ERROR_WANT_WRITE)){
                    continue;
                }else {
                    if (o.verbose) {
                        loguser("Failed SSL connection from %s: %s\n",
                        inet_socktop(&info->remoteaddr),
                                     ERR_error_string(ERR_get_error(), NULL));
                    }
                    goto loop_end;
                }
            }

David Fifield
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