Re: AS PATH limits

[Hank Nussbacher <hank () efes iucc ac il>]

On 01/10/2017 04:28, Christopher Morrow wrote:
> On Sat, Sep 30, 2017 at 12:47 PM, Ken Chase <math () sizone org> wrote:
>
> > I dont see that as the solution. Someone else will offend again.
> >
> > However, I also don't see trusting major backbones as our filters (for many
> > other reasons). Our software should be handling what's effectively a
> > buffer overflow
> > or equivalent (beware long paths that are actually shellcode).
> >
> > Quagga among others seems to be subject to this bug, pre 0.99.23 or so
> > (.99.24+ seems ok). So upgrading is a solution.
> ii  quagga              0.99.22.4-3ubu i386           BGP/OSPF/RIP routing
> daemon
>
> interestingly enough that isn't crashlooping nor is it bouncing bgp
> sessions:

https://cve.mitre.org/cgi-bin/cvename.cgi?name=2009-1572
Quagga 0.99.11 and earlier affected.
Fixed in 2009.

-Hank


> 192.168.100.100  4 MYASN 1642717    8864        0    0    0 2d23h32m
> 672475
>
> and it's happily showing me the route even...
>
> There was also some chatter on the quagga mailing list on how it's more
> > pleasant to stab your eyeballs out rather than constructing extremely long
> > regexp's that might work as a filter.
> >
> > https://lists.quagga.net/pipermail/quagga-users/2017-September/thread.html
> >
> > /kc
> >
> >
> > On Sat, Sep 30, 2017 at 05:30:03PM +0200, Niels Raijer said:
> >   >My message to NANOG about this from 12:31 UTC today is still in the
> > moderation queue. I had opened a support case with Cogent before writing my
> > message to NANOG and Cogent has let me know approximately 40 minutes ago
> > that they have contacted their customer.
> >   >
> >   >Niels
> >   >
> >   >
> >   >
> >   >On 30 Sep 2017, at 17:09, sthaug () nethelp no wrote:
> >   >
> >   >>> If you're on cogent, since 22:30 UTC yesterday or so this has been
> > happening
> >   >>> (or happened).
> >   >>
> >   >> Still happening here. I count 562 prepends (563 * 262197) in the
> >   >> advertisement we receive from Cogent. I see no good reason why we
> >   >> should accept that many prepends.
> >   >>
> >   >> Steinar Haug, Nethelp consulting, sthaug () nethelp no
> >   >
> >
> > --
> > Ken Chase - math () sizone org  Guelph Canada