Re: [v6ops] [OPSEC] [EXTERNAL] Re: [IPv6] Why folks are blocking IPv6 extension headers? (Episode 1000 and counting) (Linux DoS)

[Warren Kumari <[e-mail]>]

On Fri, May 26, 2023 at 11:13 AM, Ole Troan <[e-mail]> wrote:

> A well-implemented host will not be troubled by unkown extension headers
> or options.
>
> Indeed. However, not all hosts are well-implemented.
>
> "Not be troubled by” == “drop”?
>

I had assumed "not troubled by" meant "doesn't explode, killing everyone
inside".

I'd assume that no-one is thinking that a host or application should try
and process an extension header that it doesn't understand… but then again,
I'm often wrong in my assuimptions.

W


> I don’t agree that a well-implemented host and application should blindly
> accept any and all extension headers. If my application cannot use those
> extension headers why do you send them to me? If they are purely for the
> use in the network, then again why do you expose them to the application?
>
> If you can give some practical examples where it’s beneficial to “process”
> unknown extension headers by hosts/applications, then this may be a little
> easier to reason over.
>
> O.
>