mailing list archives
Re: BCP38 tester?
From: Alain Hebert <ahebert () pubnix net>
Date: Mon, 01 Apr 2013 09:34:31 -0400
On 04/01/13 04:02, Karl Auer wrote:
On Mon, 2013-04-01 at 01:31 -0500, Jimmy Hess wrote:
On 3/31/13, Karl Auer <kauer () biplane com au> wrote:
OK - how does one configure NAT so that the source addresses of outbound
packets are NOT clamped to a configured range on the outside of the NAT
device? Given this general scenario, of course:
He said it depends on how NAT is configured
In some implementations, only certain ranges of source IP addresses
are subject to translation.
Um - if no address translation takes place, then, by definition, NAT has
not taken place.
So it may well be that a particular device, capable of doing NAT and
other things, of NATting some packets but not others, may permit
spoofed-because-not-NATted outbound packets, but I remain unconvinced
that a spoofed packet can make it through a NAT process and head
outbound without getting its source address clamped to a configured
range of outside addresses.
Now I'm imagining a NAT process that translates only *destination*
addresses - hm, is there such a beast?
Continuing to seek enlightenment...
While I was reading this... thinking that a NAT is a NAT is a NAT...
( I spend "some" time writing/porting NAT code in my youth )
I'm sad to confirm that my spoof test was successful with a:
. SageMCom modem+router, which is used by a big TelCo around my
part, for both their residential and commercial ADSL2+, VDSL customers.
. 4 well know Tier-2(?) provider :( why I'm wasting time filling
up "paper" LoA if its only going to be used for BGP.
But on the other hand... it failed on a:
. Cisco (*cought* LinkSys) WRT54G loaded with DD-WRT v2.4-sp2
. SonicWall 2040 with 126.96.36.199;
. Thompson SpeedTouch 516;
( I'm looking around for more CPE I could "use", for testing =D )
PS: I'm not promoting the listed vendor, products. Its only a quick
test with what I had on my hand during breakfast.
Alain Hebert ahebert () pubnix net
50 boul. St-Charles
P.O. Box 26770 Beaconsfield, Quebec H9W 6G7
Tel: 514-990-5911 http://www.pubnix.net Fax: 514-990-9443
Re: BCP38 tester? Peter Baldridge (Apr 01)
Re: BCP38 tester? Jima (Apr 01)
Re: BCP38 tester? Jay Ashworth (Apr 01)
RE: BCP38 tester? Frank Bulk \(iname.com\) (Apr 01)