Commit 6a5f44d7 authored by Timo Teras's avatar Timo Teras Committed by David S. Miller
Browse files

[IPV4] ip_gre: sendto/recvfrom NBMA address 



When GRE tunnel is in NBMA mode, this patch allows an application to use
a PF_PACKET socket to:
- send a packet to specific NBMA address with sendto()
- use recvfrom() to receive packet and check which NBMA address it came from

This is required to implement properly NHRP over GRE tunnel.

Signed-off-by: default avatarTimo Teras <timo.teras@iki.fi>
Acked-by: default avatarAlexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 16d14ef9

net/ipv4/ip_gre.c

+11 −1
Original line number Diff line number Diff line
@@ -1033,7 +1033,6 @@ static int ipgre_tunnel_change_mtu(struct net_device *dev, int new_mtu) 
	return 0;

}



#ifdef CONFIG_NET_IPGRE_BROADCAST

/* Nice toy. Unfortunately, useless in real life :-)

   It allows to construct virtual multiprotocol broadcast "LAN"

   over the Internet, provided multicast routing is tuned.
@@ -1092,10 +1091,19 @@ static int ipgre_header(struct sk_buff *skb, struct net_device *dev, 
	return -t->hlen;

}



static int ipgre_header_parse(const struct sk_buff *skb, unsigned char *haddr)

{

	struct iphdr *iph = (struct iphdr*) skb_mac_header(skb);

	memcpy(haddr, &iph->saddr, 4);

	return 4;

}



static const struct header_ops ipgre_header_ops = {

	.create	= ipgre_header,

	.parse	= ipgre_header_parse,

};



#ifdef CONFIG_NET_IPGRE_BROADCAST

static int ipgre_open(struct net_device *dev)

{

	struct ip_tunnel *t = netdev_priv(dev);
@@ -1197,6 +1205,8 @@ static int ipgre_tunnel_init(struct net_device *dev) 
			dev->stop = ipgre_close;

		}

#endif

	} else {

		dev->header_ops = &ipgre_header_ops;

	}



	if (!tdev && tunnel->parms.link)

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