Re: Scannning

On Mon, 19 Mar 2007, Tambet Ingo wrote:
There are multiple problems when trying to "fix" this behavior:

* Scanning disables all other operations on card so network doesn't work at
that time. That's the reason there is a timeout, that's the reason there
can't be a "scan now" button (well, part of the reason anyway). We need to
protect NM from malicious users who can write a shell script to make NM scan
constantly (or if they're not smart enough, keep hitting that
button/activating the menu manually). [1]

[1] I'm not sure how serious that is since any user can just deactivate all
networking anyway.

The idea of preventing a user from intentionally launching a DoS attack on his own service seems strange to me. As you say, if a user wants to deny himself a service, all he needs to do is turn it off. (If NM is intended to manage networks on a truely multi-user system, that's different. But that's not how I ever envisioned it. I don't use NM on my workstations because they don't need the dynamic network management facility. I just don't think of laptops as "real" multi-user systems.)

Accidental self-DoS is a different issue. One thing that occurs to me is simply not rescheduling the scan if the menu is opened within the 20-second interval. Then a user can just reopen the menu every few seconds and see if it's been updated. There's no way to really cancel a scheduled scan, so what's wrong with just letting it go once scheduled?

		Matthew Saltzman

Clemson University Math Sciences
mjs AT clemson DOT edu

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