From mboxrd@z Thu Jan  1 00:00:00 1970
From: Harald Welte <laforge@netfilter.org>
Subject: Re: [PATCH]: 1st step to remove skb_linearize() in ip6_tables.c and optimization
Date: Sun, 1 Aug 2004 18:46:53 +0200
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Cc: kadlec@blackhole.kfki.hu, kaber@trash.net,
	netfilter-devel@lists.netfilter.org, kisza@securityaudit.hu,
	usagi-core@linux-ipv6.org
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To: Yasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp>
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On Thu, Jul 29, 2004 at 03:09:02PM +0900, Yasuyuki Kozakai wrote:
> I got time to implement your idea. How about this ? (not tested)
>
> 	struct tcphdr hdr;
> 	struct tcphdr *tcph
>=20
> 	tcph =3D skb_get_bits(skb, &hdr, skb->nh.iph->ihl*4, sizeof(hdr));
>=20
> If skb is neither shared nor cloned, this function linearize up to tcp he=
ader
> and returns the pointer to tcp header in skb.
>=20
> Otherwise, copies tcp header to "hdr" and return the pointer to it.
> If error, return NULL.

This sounds like a very sane approach to me. =20

Since we don't have stable API's in 2.6.x anymore (kernel summit
decision), we could even put this in our pending queue of patches for
something like 2.6.10/2.6.11

What does eveybody else think?  Comments?

--=20
- Harald Welte <laforge@netfilter.org>             http://www.netfilter.org/
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
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=3D
  "Fragmentation is like classful addressing -- an interesting early
   architectural error that shows how much experimentation was going
   on while IP was being designed."                    -- Paul Vixie

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