Return-path: Received: from mail-fx0-f46.google.com ([209.85.161.46]:54172 "EHLO mail-fx0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750826Ab0EIUYa convert rfc822-to-8bit (ORCPT ); Sun, 9 May 2010 16:24:30 -0400 Received: by fxm10 with SMTP id 10so1866997fxm.19 for ; Sun, 09 May 2010 13:24:28 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <4BE46584.5060304@create-net.org> References: <4BE43C18.2030806@create-net.org> <4BE46584.5060304@create-net.org> From: =?ISO-8859-1?Q?G=E1bor_Stefanik?= Date: Sun, 9 May 2010 22:24:08 +0200 Message-ID: Subject: Re: Packet injection with ath9k To: Roberto Riggio Cc: linux-wireless@vger.kernel.org Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-wireless-owner@vger.kernel.org List-ID: 2010/5/7 Roberto Riggio : > Hi, > > well, that is what i wanted to understand. These are the struct > that I'm using to compose the rediotap header: > > struct ieee80211_radiotap_header { > ? ?u_int8_t ? ?it_version; > ? ?u_int8_t ? ?it_pad; > ? ?u_int16_t ? ? ? it_len; > ? ?u_int32_t ? ? ? it_present; AFAIK these 2 fields need to be little-endian even on big-endian machines. If your system is big-endian, this can cause problems. > } __attribute__((__packed__)); > > struct click_radiotap_header { > ? ?struct ieee80211_radiotap_header wt_ihdr; > ? ?u_int8_t ? ?wt_rate; > ? ?u_int8_t ? ?wt_txpower; > ? ?u_int8_t ? ? ? ?wt_rts_retries; > ? ?u_int8_t ? ? ? ?wt_data_retries; > }; > > The flags are set in order to take into account the fields that I > specify. But i do not know at which point the frame are > dropped. > > R. > > On 05/07/2010 06:35 PM, G?bor Stefanik wrote: >> >> Hi! >> Are you sure it is not your injector that is having alignment issues? >> AFAIK the radiotap parser explicitly uses endianness-aware function >> everywhere. >> >> On Fri, May 7, 2010 at 6:13 PM, Roberto Riggio >> ?wrote: >> >>> >>> Hi, >>> >>> I'm writing an application to inject traffic over a wireless interface. >>> This >>> app >>> is working fine on an x86 machine. However if i compile the same app for >>> an arm platform, no frame are sent over the wireless interface (ath9k). >>> >>> I'm guessing that this is because of some alignment issues but i cannot >>> track >>> the piece of code that is actually parsing the frame. I've found the >>> __ieee80211_parse_tx_radiotap in net/mac80211/tx.c function, but it is >>> not called when i try to inject some traffic, so the frame are dropped >>> before that. >>> >>> Any hints? >>> >>> Thanks >>> R. >>> -- >>> To unsubscribe from this list: send the line "unsubscribe linux-wireless" >>> in >>> the body of a message to majordomo@vger.kernel.org >>> More majordomo info at ?http://vger.kernel.org/majordomo-info.html >>> >>> >> >> >> > > -- Vista: [V]iruses, [I]ntruders, [S]pyware, [T]rojans and [A]dware. :-)