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Re: [Captive-portals] Signals from the network and ICMP



Warren Kumari <[email protected]> wrote:
    >> The fewer privilege escalation points the better, I suppose.  From that
    >> perspective a UDP socket may be less concerning, but perhaps not by much.
    >> NetworkMonitor has the appropriate privileges to do the needful,
    > regardless.

    > I'll start off by admitting that this is a cheap shot, but:
    > https://access.redhat.com/security/vulnerabilities/3442151

(yeah, so that's as much about using shell for things it was never designed to do.)

    > I'm uncomfortable with the "let's have all machines which might possibly
    > connect to a network with a captive portal have a daemon listening on a
    > well-known UDP port" idea. Yes, it is very similar to "let's have all
    > machines which might possibly connect to a network with a captive portal
    > have a thingie watching for special ICMP messages", but somehow it feels
    > very different. Yes, I understand the irony of building networks based on
    > what makes Warren uncomfortable,  but...

I agree, it's different. ICMP is generally handled centrally by the kernel,
and it isn't handed off to random shell scripts.  The kernel does some
validation of the incoming packet.


--
Michael Richardson <[email protected]>, Sandelman Software Works
 -= IPv6 IoT consulting =-



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