Regarding parsing of cifs header

[Ramana Reddy]

Hi Pranay Srivastava,

Thanks for your reply.  I just want to copy the payload into the buffer
with out cloning
or copying of skb to reduce the delay as it has to do on every packet.
Is there any method in the linux kernel to get only the payload after
stripping off the
TCP header.

Thanks,
Ramana.


On Mon, May 26, 2014 at 2:17 PM, Pranay Srivastava <pranjas at gmail.com>wrote:

> On Mon, May 26, 2014 at 1:20 PM, Ramana Reddy <gtvrreddy at gmail.com> wrote:
> > Thanks for your reply. First thing is that I do not want to modify the
> > existing cifs driver.
> > I have my own virtual Ethernet driver, where the skb buffer is available
> to
> > parse. Now,
> > I want to extract the cifs header from this skb buffer, and based on the
> > cifs header contents
> > ( mainly I am looking for return status), I have to redirect the packet
> to
> > different destination.
>
> skb_clone in case you won't modify the packet. (Data isn't copied here).
>
> skb_copy if you or the intended recipient would modify the skb.(Data
> is copied here). Gives you a free pass to do anything.
>
> For UDP packets I guess you'll also need to take off the UDP header
> (last time I tried to read from skb of a UDP) but for TCP you'll have
> your data ready no need
> to strip off the TCP header. Just check in case the skb you've
> contains fragments(For TCP connection) but since you only need CIFS
> header I don't think you'll have to bother about that, as CIFS header
> isn't that big.
>
> >
> > Thanks,
> > Ramana.
> >
> >
> > On Mon, May 26, 2014 at 12:34 PM, <Valdis.Kletnieks at vt.edu> wrote:
> >>
> >> On Mon, 26 May 2014 12:21:12 +0530, Ramana Reddy said:
> >>
> >> > I would like to know how to extract the cifs protocol header from skb
> >> > buffer in the linux
> >> > kernel. I want to parse the cifs header and do some stuff based on the
> >> > content of the header.
> >>
> >> Depending what you are trying to do, it may be best to add your code
> >> to the CIFS driver at the points where the driver is examining the
> >> header fields in question.
> >>
> >> What "do some stuff" are you trying to achieve?
> >
> >
> >
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>
>
>
> --
>         ---P.K.S
>
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