LXR linux/net/802/p8022.c

   1/*
   2 *      NET3:   Support for 802.2 demultiplexing off Ethernet
   3 *              This program is free software; you can redistribute it and/or
   4 *              modify it under the terms of the GNU General Public License
   5 *              as published by the Free Software Foundation; either version
   6 *              2 of the License, or (at your option) any later version.
   7 *
   8 *              Demultiplex 802.2 encoded protocols. We match the entry by the
   9 *              SSAP/DSAP pair and then deliver to the registered datalink that
  10 *              matches. The control byte is ignored and handling of such items
  11 *              is up to the routine passed the frame.
  12 *
  13 *              Unlike the 802.3 datalink we have a list of 802.2 entries as
  14 *              there are multiple protocols to demux. The list is currently
  15 *              short (3 or 4 entries at most). The current demux assumes this.
  16 */
  17#include <linux/module.h>
  18#include <linux/netdevice.h>
  19#include <linux/skbuff.h>
  20#include <linux/slab.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