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Date: Wed, 23 Jun 2004 14:45:47 -0400 (EDT)
From: rahul b jain cs student <rbj2@oak.njit.edu>
To: linux-kernel@vger.kernel.org
Subject: Question about ip_rcv() function
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Hi,

can anyone explain what is the difference between the following two pieces
of code.

1. if (!pskb_may_pull(skb, sizeof(struct iphdr)))
                goto inhdr_error;

   iph = skb->nh.iph;

2. if (!pskb_may_pull(skb, iph->ihl*4))
                goto inhdr_error;

   iph = skb->nh.iph;


Also, does anyone know how the headers are stripped from the packet at the
receiving end. Does the function __pskb_pull_tail() strip of the header fields ?

Thanks,
Rahul.