Commit 2606aff9 authored by Jason A. Donenfeld's avatar Jason A. Donenfeld Committed by David S. Miller
Browse files

net: ip_tunnel: add header_ops for layer 3 devices 



Some devices that take straight up layer 3 packets benefit from having a
shared header_ops so that AF_PACKET sockets can inject packets that are
recognized. This shared infrastructure will be used by other drivers
that currently can't inject packets using AF_PACKET. It also exposes the
parser function, as it is useful in standalone form too.

Signed-off-by: default avatarJason A. Donenfeld <Jason@zx2c4.com>
Acked-by: default avatarWillem de Bruijn <willemb@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent bf64ff4c

include/net/ip_tunnels.h

+3 −0
Original line number Diff line number Diff line
@@ -290,6 +290,9 @@ int ip_tunnel_newlink(struct net_device *dev, struct nlattr *tb[], 
		      struct ip_tunnel_parm *p, __u32 fwmark);

void ip_tunnel_setup(struct net_device *dev, unsigned int net_id);



extern const struct header_ops ip_tunnel_header_ops;

__be16 ip_tunnel_parse_protocol(const struct sk_buff *skb);



struct ip_tunnel_encap_ops {

	size_t (*encap_hlen)(struct ip_tunnel_encap *e);

	int (*build_header)(struct sk_buff *skb, struct ip_tunnel_encap *e,

net/ipv4/ip_tunnel_core.c

+18 −0
Original line number Diff line number Diff line
@@ -844,3 +844,21 @@ void ip_tunnel_unneed_metadata(void) 
	static_branch_dec(&ip_tunnel_metadata_cnt);

}

EXPORT_SYMBOL_GPL(ip_tunnel_unneed_metadata);



/* Returns either the correct skb->protocol value, or 0 if invalid. */

__be16 ip_tunnel_parse_protocol(const struct sk_buff *skb)

{

	if (skb_network_header(skb) >= skb->head &&

	    (skb_network_header(skb) + sizeof(struct iphdr)) <= skb_tail_pointer(skb) &&

	    ip_hdr(skb)->version == 4)

		return htons(ETH_P_IP);

	if (skb_network_header(skb) >= skb->head &&

	    (skb_network_header(skb) + sizeof(struct ipv6hdr)) <= skb_tail_pointer(skb) &&

	    ipv6_hdr(skb)->version == 6)

		return htons(ETH_P_IPV6);

	return 0;

}

EXPORT_SYMBOL(ip_tunnel_parse_protocol);



const struct header_ops ip_tunnel_header_ops = { .parse_protocol = ip_tunnel_parse_protocol };

EXPORT_SYMBOL(ip_tunnel_header_ops);

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