From: ebiederm@xmission•com (Eric W. Biederman)
To: Ani Sinha <ani@aristanetworks•com>
Cc: Michael Richardson <mcr@sandelman•ca>,
tcpdump-workers@lists•tcpdump.org, netdev@vger•kernel.org,
Francesco Ruggeri <fruggeri@aristanetworks•com>
Subject: Re: [tcpdump-workers] vlan tagged packets and libpcap breakage
Date: Thu, 06 Dec 2012 17:03:44 -0800 [thread overview]
Message-ID: <87hanyekr3.fsf@xmission.com> (raw)
In-Reply-To: <CAOxq_8NbmOtvyH6Q=AVeOUAj7DoFO8cnVUQA5sgyEG7jEJXpHA@mail.gmail.com> (Ani Sinha's message of "Thu, 6 Dec 2012 16:55:00 -0800")
Ani Sinha <ani@aristanetworks•com> writes:
> On Thu, Dec 6, 2012 at 2:19 PM, Eric W. Biederman <ebiederm@xmission•com> wrote:
>> Ani Sinha <ani@aristanetworks•com> writes:
>>>>
>>>
>>> May be this?
>>
>> Two things.
>>
>> - TP_STATUS_VLAN_VALID lives in the tp_status field not the tp_vlan_tci field.
>> - To work on older kernels with binaries compiled with newer headers you
>> first want to test for tp_vlan_tci == 0 and then look at the status field for
>> TP_STATUS_VALID.
>
>
> trying again :
The patch is whitespace damaged. And one of your test is using ||
instead of &&
Eric
> pcap-linux.c | 50 +++++++++++++++++++++++++++++++-------------------
> 1 files changed, 31 insertions(+), 19 deletions(-)
>
> diff --git a/pcap-linux.c b/pcap-linux.c
> index a42c3ac..8e355d3 100644
> --- a/pcap-linux.c
> +++ b/pcap-linux.c
> @@ -133,6 +133,7 @@ static const char rcsid[] _U_ =
> #include <sys/utsname.h>
> #include <sys/mman.h>
> #include <linux/if.h>
> +#include <linux/if_packet.h>
> #include <netinet/in.h>
> #include <linux/if_ether.h>
> #include <net/if_arp.h>
> @@ -1543,7 +1544,13 @@ pcap_read_packet(pcap_t *handle, pcap_handler
> callback, u_char *userdata)
> continue;
>
> aux = (struct tpacket_auxdata *)CMSG_DATA(cmsg);
> - if (aux->tp_vlan_tci == 0)
> +#if defined(TP_STATUS_VLAN_VALID)
> + if ((aux->tp_vlan_tci == 0) ||
> !(aux->tp_status & TP_STATUS_VLAN_VALID))
The test should be && not ||.
> +#else
> + if (aux->tp_vlan_tci == 0) /* this is ambigious but without the
> +
> TP_STATUS_VLAN_VALID flag, there is
> + nothing that we can do */
> +#endif
> continue;
>
> len = packet_len > iov.iov_len ? iov.iov_len : packet_len;
> @@ -3936,7 +3926,12 @@ pcap_read_linux_mmap(pcap_t *handle, int
> max_packets, pcap_handler callback,
> }
>
> #ifdef HAVE_TPACKET2
> - if (handle->md.tp_version == TPACKET_V2 && h.h2->tp_vlan_tci &&
> + if ((handle->md.tp_version == TPACKET_V2) &&
> +#if defined(TP_STATUS_VLAN_VALID)
> + (h.h2->tp_vlan_tci || (h.h2->tp_status &
> TP_STATUS_VLAN_VALID)) &&
> +#else
> + h.h2->tp_vlan_tci &&
> +#endif
> handle->md.vlan_offset != -1 &&
> tp_snaplen >= (unsigned int) handle->md.vlan_offset) {
> struct vlan_tag *tag;
next prev parent reply other threads:[~2012-12-07 1:03 UTC|newest]
Thread overview: 41+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <CAOxq_8Nd8VP3MaNBfUt9v82nmGDpxZz5_5QMdsruET1tjwuQPw@mail.gmail.com>
[not found] ` <3246.1351717319@obiwan.sandelman.ca>
2012-10-31 21:50 ` [tcpdump-workers] vlan tagged packets and libpcap breakage Ani Sinha
2012-10-31 22:20 ` Guy Harris
2012-10-31 22:35 ` Ani Sinha
2012-11-01 0:50 ` [tcpdump-workers] " Guy Harris
2012-11-01 1:22 ` Ani Sinha
2012-12-06 21:20 ` Ani Sinha
2012-11-02 16:13 ` Bill Fenner
2012-11-13 22:41 ` Ani Sinha
2012-11-13 22:42 ` [tcpdump-workers] " Ani Sinha
2012-11-14 18:58 ` Michael Richardson
2012-10-31 22:42 ` [tcpdump-workers] " Michael Richardson
2012-12-12 21:53 ` Ani Sinha
2012-12-12 22:16 ` Ani Sinha
2012-12-13 8:35 ` [tcpdump-workers] " Daniel Borkmann
2012-12-13 17:34 ` Ani Sinha
2012-12-13 21:49 ` Daniel Borkmann
2012-12-13 22:07 ` Ani Sinha
2012-12-17 9:50 ` David Laight
2012-12-17 10:35 ` Guy Harris
2012-12-17 11:08 ` Daniel Borkmann
2012-12-17 19:49 ` [tcpdump-workers] " Ani Sinha
2012-11-16 6:51 ` Eric W. Biederman
2012-11-17 22:14 ` Michael Richardson
2012-11-17 23:16 ` Daniel Borkmann
2012-11-17 23:37 ` Eric W. Biederman
2012-11-17 23:33 ` Eric W. Biederman
2012-12-06 21:22 ` Ani Sinha
2012-12-06 22:19 ` Eric W. Biederman
2012-12-06 22:40 ` Ani Sinha
2012-12-07 0:55 ` Ani Sinha
2012-12-07 1:03 ` Eric W. Biederman [this message]
2012-12-07 1:28 ` [tcpdump-workers] " Ani Sinha
2012-12-07 1:31 ` Ani Sinha
2012-12-07 1:41 ` Eric W. Biederman
2012-12-07 1:59 ` Michael Richardson
2012-12-11 0:11 ` [tcpdump-workers] " Ani Sinha
2012-12-11 22:36 ` Ani Sinha
2012-12-11 23:04 ` Eric Dumazet
2012-12-12 0:46 ` Ani Sinha
2012-12-12 0:50 ` [tcpdump-workers] " Ani Sinha
2012-12-11 23:12 ` Stephen Hemminger
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