1/*
2 *	NET3:	Support for 802.2 demultiplexing off Ethernet (Token ring
3 *		is kept separate see p8022tr.c)
4 *		This program is free software; you can redistribute it and/or
5 *		modify it under the terms of the GNU General Public License
6 *		as published by the Free Software Foundation; either version
7 *		2 of the License, or (at your option) any later version.
8 *
9 *		Demultiplex 802.2 encoded protocols. We match the entry by the
10 *		SSAP/DSAP pair and then deliver to the registered datalink that
11 *		matches. The control byte is ignored and handling of such items
12 *		is up to the routine passed the frame.
13 *
14 *		Unlike the 802.3 datalink we have a list of 802.2 entries as
15 *		there are multiple protocols to demux. The list is currently
16 *		short (3 or 4 entries at most). The current demux assumes this.
17 */
18#include <linux/module.h>
19#include <linux/netdevice.h>
20#include <linux/skbuff.h>
21#include <net/datalink.h>
22#include <linux/mm.h>
23#include <linux/in.h>
24#include <linux/init.h>
25#include <net/llc.h>
26#include <net/p8022.h>
27
28static int p8022_request(struct datalink_proto *dl, struct sk_buff *skb,
29			 unsigned char *dest)
30{
31	llc_build_and_send_ui_pkt(dl->sap, skb, dest, dl->sap->laddr.lsap);
32	return 0;
33}
34
35struct datalink_proto *register_8022_client(unsigned char type,
36					    int (*func)(struct sk_buff *skb,
37							struct net_device *dev,
38							struct packet_type *pt,
39							struct net_device *orig_dev))
40{
41	struct datalink_proto *proto;
42
43	proto = kmalloc(sizeof(*proto), GFP_ATOMIC);
44	if (proto) {
45		proto->type[0]		= type;
46		proto->header_length	= 3;
47		proto->request		= p8022_request;
48		proto->sap = llc_sap_open(type, func);
49		if (!proto->sap) {
50			kfree(proto);
51			proto = NULL;
52		}
53	}
54	return proto;
55}
56
57void unregister_8022_client(struct datalink_proto *proto)
58{
59	llc_sap_put(proto->sap);
60	kfree(proto);
61}
62
63EXPORT_SYMBOL(register_8022_client);
64EXPORT_SYMBOL(unregister_8022_client);
65
66MODULE_LICENSE("GPL");
67