RadioTap Archive on lore.kernel.org
 help / color / Atom feed
* Assigning a new DLT_ value for "standardized" radiotap?
@ 2010-02-17  2:08 Guy Harris
       [not found] ` <5F21AFA5-4D4C-49A0-A228-A1177630E366-FrUbXkNCsVf2fBVCVOL8/A@public.gmane.org>
  0 siblings, 1 reply; 4+ messages in thread
From: Guy Harris @ 2010-02-17  2:08 UTC (permalink / raw)
  To: radiotap-sUITvd46vNxg9hUCZPvPmw

The presence-bit-number collisions mentioned on the radiotap Web site appear to be due to OpenBSD doing its own thing:

	14: FCS in OpenBSD, RX Flags in the standard and assigned for that in NetBSD and Linux
	15: hardware queue in OpenBSD, proposed for TX flags in the standard and assigned for that in NetBSD and Linux
	16: RSSI in OpenBSD, proposed for RTS Retries in the standard and assigned for that in NetBSD and Linux

(There was also a brief period of time, between 2007-06-11 and 2007-07-01, where FreeBSD used 14 for the extended channel information, but it got moved to 18; it appears that was done before FreeBSD 7.0 got released, so it doesn't appear that any *released* version used 14 for the extended channel information.)

I've filed an bug against this:

	http://cvs.openbsd.org/cgi-bin/query-pr-wrapper?full=yes&numbers=5691

but nothing has been done for it; I've also asked Reyk Floeter about it, and heard nothing.  I forget whether I've asked Damien Bergamini about it or not.

Unfortunately, there are probably both OpenBSD and NetBSD/Linux captures out there with a network type value of 127, so we can't easily make tcpdump or Wireshark or... handle both automatically (a command-line flag for tcpdump and a preference for Wireshark could be used).  If we were to introduce a new DLT_ value for "standard radiotap", tcpdump and Wireshark could unconditionally interpret those presence bit values as having the NetBSD/Linux meaning, and use a flag/preference or whatever for the existing value (or just blow off OpenBSD).

Would that be useful?

^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: Assigning a new DLT_ value for "standardized" radiotap?
       [not found] ` <5F21AFA5-4D4C-49A0-A228-A1177630E366-FrUbXkNCsVf2fBVCVOL8/A@public.gmane.org>
@ 2010-02-17  8:27   ` Johannes Berg
       [not found]     ` <1266395272.4006.0.camel-8upI4CBIZJIJvtFkdXX2HixXY32XiHfO@public.gmane.org>
  0 siblings, 1 reply; 4+ messages in thread
From: Johannes Berg @ 2010-02-17  8:27 UTC (permalink / raw)
  To: Guy Harris; +Cc: radiotap-sUITvd46vNxg9hUCZPvPmw

[-- Attachment #1: Type: text/plain, Size: 368 bytes --]

On Tue, 2010-02-16 at 18:08 -0800, Guy Harris wrote:
> The presence-bit-number collisions mentioned on the radiotap Web site
> appear to be due to OpenBSD doing its own thing:
> 
> 	14: FCS in OpenBSD, RX Flags in the standard and assigned for that in
> NetBSD and Linux

Didn't I go and add a preferences setting to wireshark for this
collision?

johannes

[-- Attachment #2: This is a digitally signed message part --]
[-- Type: application/pgp-signature, Size: 801 bytes --]

^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: Assigning a new DLT_ value for "standardized" radiotap?
       [not found]     ` <1266395272.4006.0.camel-8upI4CBIZJIJvtFkdXX2HixXY32XiHfO@public.gmane.org>
@ 2010-02-17  8:38       ` Gábor Stefanik
       [not found]         ` <69e28c911002170038q2a401120l369b5dffaa016e01-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
  0 siblings, 1 reply; 4+ messages in thread
From: Gábor Stefanik @ 2010-02-17  8:38 UTC (permalink / raw)
  To: Johannes Berg; +Cc: Guy Harris, radiotap-sUITvd46vNxg9hUCZPvPmw

On Wed, Feb 17, 2010 at 9:27 AM, Johannes Berg
<johannes-cdvu00un1VgdHxzADdlk8Q@public.gmane.org> wrote:
> On Tue, 2010-02-16 at 18:08 -0800, Guy Harris wrote:
>> The presence-bit-number collisions mentioned on the radiotap Web site
>> appear to be due to OpenBSD doing its own thing:
>>
>>       14: FCS in OpenBSD, RX Flags in the standard and assigned for that in
>> NetBSD and Linux
>
> Didn't I go and add a preferences setting to wireshark for this
> collision?
>
> johannes
>

Yes, but Guy is talking about auto-detection.

-- 
Vista: [V]iruses, [I]ntruders, [S]pyware, [T]rojans and [A]dware. :-)

^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: Assigning a new DLT_ value for "standardized" radiotap?
       [not found]         ` <69e28c911002170038q2a401120l369b5dffaa016e01-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
@ 2010-02-17 18:49           ` Guy Harris
  0 siblings, 0 replies; 4+ messages in thread
From: Guy Harris @ 2010-02-17 18:49 UTC (permalink / raw)
  To: radiotap-sUITvd46vNxg9hUCZPvPmw


On Feb 17, 2010, at 12:38 AM, Gábor Stefanik wrote:

> Yes, but Guy is talking about auto-detection.

Or, at least, semi-automatic - the preference would be ignored for the new DLT_ value, as those captures always use the standard presence bit values; it would be needed only for the old DLT_ value.

^ permalink raw reply	[flat|nested] 4+ messages in thread

end of thread, back to index

Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2010-02-17  2:08 Assigning a new DLT_ value for "standardized" radiotap? Guy Harris
     [not found] ` <5F21AFA5-4D4C-49A0-A228-A1177630E366-FrUbXkNCsVf2fBVCVOL8/A@public.gmane.org>
2010-02-17  8:27   ` Johannes Berg
     [not found]     ` <1266395272.4006.0.camel-8upI4CBIZJIJvtFkdXX2HixXY32XiHfO@public.gmane.org>
2010-02-17  8:38       ` Gábor Stefanik
     [not found]         ` <69e28c911002170038q2a401120l369b5dffaa016e01-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2010-02-17 18:49           ` Guy Harris

RadioTap Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/radiotap/0 radiotap/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 radiotap radiotap/ https://lore.kernel.org/radiotap \
		radiotap@radiotap.org
	public-inbox-index radiotap

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.netbsd.radiotap


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git