Wireshark-dev: Re: [Wireshark-dev] [Wireshark-commits] master 64cd827: Have dissect_usb_setup_r
From: Pascal Quantin <[email protected]>
Date: Tue, 26 Aug 2014 12:09:02 +0200
Hi Martin,

2014-08-26 12:05 GMT+02:00 Martin Kaiser <[email protected]>:

The new req_type is the same as the existing type. There's a
switch(type) {...} followed by in if (req_type==...).

My goal is to have only one call to try_dissect_next_protocol(). In
dissect_usb_common(), we dissect the standard fields in the main
switch-statement and call try_dissect_next_protocol() _once_ for the
remaining data.

At the moment, try_dissect_next_protocol() is called
twice for control requests that it can't handle. This adds two generated
items saying "unknown class".

I spotted a regression myself (that seems similar to what you report) and proposed https://code.wireshark.org/review/#/c/3858/ to fix it. Could you give it a try on your sample?


Unfortunately, the recent patches make it harder to fix this...

Why is the setup_tvb for the standard setup request generated in

if (header_info & (USB_HEADER_IS_LINUX | USB_HEADER_IS_64_BYTES)) {
else {
        offset = try_dissect_linux_usb_pseudo_header_ext(tvb, offset, pinfo, tree, header_info);

Will try_dissect_linux_usb_pseudo_header_ext() ever do anything if it's
only called when there's no extended pseudo header?

Is there a way to "subscribe" to gerrit change requests so that I'm
notified when a new USB-related change is uploaded?

Thus wrote Wireshark code review ([email protected]):

> URL: https://code.wireshark.org/review/gitweb?p=wireshark.git;a=commit;h=64cd8270c669e35bc2911133a9a7da31c4bb1965
> Submitter: Anders Broman ([email protected])
> Changed: branch: master
> Repository: wireshark

> Commits:

> 64cd827 by Sean O. Stalley ([email protected]):

>     Have dissect_usb_setup_request handle non-standard requests

>     Moved code for parsing non-standard setup requests from
>     dissect_usb_common() to dissect_usb_setup_request().

>     Also added header_info flag USB_HEADER_IS_MAUSB & updated mausb
>     dissector.

>     Change-Id: Ifa8abccbd57bf4dd3965f582872952383e6f737d
>     Reviewed-on: https://code.wireshark.org/review/3851
>     Petri-Dish: Anders Broman <[email protected]>
>     Reviewed-by: Anders Broman <[email protected]>

> Actions performed:

>     from  3d4d021   Non-standard USB control requests now handled in own function
>     adds  64cd827   Have dissect_usb_setup_request handle non-standard requests

> Summary of changes:
>  epan/dissectors/packet-mausb.c |    9 +++----
>  epan/dissectors/packet-usb.c   |   51 ++++++++++++++++++++++------------------
>  epan/dissectors/packet-usb.h   |    7 ++++--
>  3 files changed, 38 insertions(+), 29 deletions(-)
> ___________________________________________________________________________
> Sent via:    Wireshark-commits mailing list <[email protected]>
> Archives:    http://www.wireshark.org/lists/wireshark-commits
> Unsubscribe: https://wireshark.org/mailman/options/wireshark-commits
>              mailto:[email protected]?subject=unsubscribe
Sent via:    Wireshark-dev mailing list <[email protected]>
Archives:    http://www.wireshark.org/lists/wireshark-dev
Unsubscribe: https://wireshark.org/mailman/options/wireshark-dev
             mailto:[email protected]?subject=unsubscribe