From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from sc8-sf-mx1-b.sourceforge.net ([10.3.1.11] helo=sc8-sf-mx1.sourceforge.net) by sc8-sf-list1.sourceforge.net with esmtp (Exim 4.30) id 1AjhD1-0007UH-9R for user-mode-linux-devel@lists.sourceforge.net; Thu, 22 Jan 2004 07:57:31 -0800 Received: from [12.177.129.25] (helo=ccure.user-mode-linux.org) by sc8-sf-mx1.sourceforge.net with esmtp (TLSv1:DES-CBC3-SHA:168) (Exim 4.30) id 1AjhD0-00079q-EA for user-mode-linux-devel@lists.sourceforge.net; Thu, 22 Jan 2004 07:57:30 -0800 From: Jeff Dike Subject: Re: [uml-devel] Changes to port_user Message-ID: <20040122162014.GA2895@ccure.user-mode-linux.org> References: <20040122144020.GQ4203@erizo.shearer.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20040122144020.GQ4203@erizo.shearer.org> Sender: user-mode-linux-devel-admin@lists.sourceforge.net Errors-To: user-mode-linux-devel-admin@lists.sourceforge.net List-Unsubscribe: , List-Id: The user-mode Linux development list List-Post: List-Help: List-Subscribe: , List-Archive: Date: Thu, 22 Jan 2004 11:20:14 -0500 To: Dan Shearer Cc: user-mode-linux-devel@lists.sourceforge.net On Fri, Jan 23, 2004 at 01:10:20AM +1030, Dan Shearer wrote: > I've done some minor work in drivers/port_user.c, including replacing > the binding to INADDR_ANY with a gethostbyname(passed_ip), so you > can specify which single IP to listen on. Cool, that's needed doing for a while. > Now what I'm trying to do is replace in.telnetd with something else, for > the moment netcat as a simple case, or something that gives the same > effect. If you want to be able to telnet to the port, then you need something which speaks telnet, hence you need telnetd. If you can connect with something else and have terminal stuff continue to work, and replace the telnetd dependency with something that works more widely out of the box, then I'm all for it. > That involves understanding the significance of port_helper and > kernel/helper.c, which I don't yet. What happens is that UML runs telnetd with the port helper as its "login" program (problem - not every telnetd out there supports -L, even if it is installed, which it often isn't). When there's a connection, UML gets a descriptor with the telnet on the other end. It needs to get telnetd talking on that to do the telnet protocol and another descriptor coming out of telnetd with actual characters that the user typed. So, it does this as follows: it execs telnetd with stdin, stderr, stdout duped from the portal file descriptor telnetd also gets a unix socket on descriptor 3 port_helper gets the desired telnetd output descriptor on its stdin/stdout it passes this back to UML over the unix socket on descriptor 3 which it inherited from telnetd Jeff ------------------------------------------------------- The SF.Net email is sponsored by EclipseCon 2004 Premiere Conference on Open Tools Development and Integration See the breadth of Eclipse activity. February 3-5 in Anaheim, CA. http://www.eclipsecon.org/osdn _______________________________________________ User-mode-linux-devel mailing list User-mode-linux-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel