From mboxrd@z Thu Jan  1 00:00:00 1970
From: Max Krasnyansky <maxk@qualcomm.com>
Subject: Re: tun device - bug or feature? WAS(Re: IMQ / new Dummy device
	post.
Date: Mon, 26 Apr 2004 12:31:38 -0700
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Cc: netdev@oss.sgi.com, syrius.ml@no-log.org, Jeff Garzik <jgarzik@pobox.com>,
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On Sat, 2004-04-24 at 07:14, jamal wrote:
> Maxim,
> 
> When TUN_TUN_DEV is used, before the packet is injected into
> the netif_rx() only skb->mac.raw = skb->data is set; the other headers
> are not adjusted. Typically netdevs would do a
> skb_pull(skb,dev->hard_header_len) to make the adjustment.
> I have a feeling this is design intent thats why i didnt send you a
> patch. 
Well TUN does not have any hw headers so there is nothing to pull :).
Basically it does what ever PPP driver does. Which is

	skb_pull(skb, 2);       /* chop off protocol */
        skb->dev = ppp->dev;
        skb->protocol = htons(npindex_to_ethertype[npi]);
        skb->mac.raw = skb->data;
        netif_rx(skb);

Max