lkml.org 
[lkml]   [1999]   [Feb]   [28]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRe: ppp mru/mtu and ip masquerading
Date
> > (If you think about it masquerading doesnt kick in on a download problem 
> > error case. The errored tcp frame bounces off the start of the low MTU
> > PPP link before it is masqueraded)
>
> There is a known bug with masquerading and path mtu discovery in 2.2. Icmp
> forgets to unmasquerade an already masqueraded packet, so the ICMP payload
> header contains the wrong address and the other end drops it.
>
> For NAT it is handled in icmp.c, but not for Masquerading
> currently. Fix is a bit more complex though because unlike NAT the
> masquerading rule is not easily accessable from the skb.

Not for the case described.

--1500 MTU---PPP gate-------------512---------MASQhost------1500---MASQ

So the MTU problem is coming off the PPP gateway host which is the ISP itself.
I can believe the masq code has a bug in 2.2.x - but note that it doesnt
get triggered inthe described scenario (just some others)


-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 13:50    [W:0.054 / U:0.140 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site