On Fri, Jan 23, 2009 at 2:33 PM, Alan McKinnon <[email protected]> wrote: > On Friday 23 January 2009 22:22:17 Paul Hartman wrote: >> I essentially want it to work the other way around. Deny access by >> default unless there is an allow rule. I don't think I can do that, >> though. If I put ALL: ALL or sshd: ALL in the hosts.deny file, it will >> deny ME access to my own machine. I don't want that. Since I don't >> have a specific IP i will connect from, I can't allow any specific IP >> (or else I'd be doing it that way already). >> >> How can I accomplish this?: >> >> Allow all ssh connections unless they are in hosts.deny >> Deny all other connections unless they are in hosts.allow > > Have you looked at port knocking? > > It's a complete ball ache to set up and use, far less useful than it seems, > but it might also solve your conundrum. > > A friend once mentioned on a forum that he'd managed to set up static libwrap > rules in hosts.allow|deny for addresses that don't change and additionally > port-knocking for himself to open up port 22 for a few minutes. I don't > recall how he did this, only that he claimed to have done it.
I've never tried it but I have always liked the idea. I connect to sshd from linux (my laptop), windows (my work desktop) and symbian (my phone). knockd and the knocking client should be no problem for linux & windows, but for my phone I'd probably have to make one myself. Is it as simple as making a connection to a specific sequence of ports with specific timing? I could probably do that easily in python. Sounds like a project for this weekend. :) thanks, paul
