LXR linux/net/ipv6/protocol.c

   1/*
   2 * INET         An implementation of the TCP/IP protocol suite for the LINUX
   3 *              operating system.  INET is implemented using the  BSD Socket
   4 *              interface as the means of communication with the user level.
   5 *
   6 *              PF_INET6 protocol dispatch tables.
   7 *
   8 * Authors:     Pedro Roque     <roque@di.fc.ul.pt>
   9 *
  10 *              This program is free software; you can redistribute it and/or
  11 *              modify it under the terms of the GNU General Public License
  12 *              as published by the Free Software Foundation; either version
  13 *              2 of the License, or (at your option) any later version.
  14 */
  15
  16/*
  17 *      Changes:
  18 *
  19 *      Vince Laviano (vince@cs.stanford.edu)       16 May 2001
  20 *      - Removed unused variable 'inet6_protocol_base'
  21 *      - Modified inet6_del_protocol() to correctly maintain copy bit.
  22 */
  23#include <linux/module.h>
  24#include <linux/netdevice.h>
  25#include <linux/spinlock.h>
  26#include <net/protocol.h>
  27
  28const struct inet6_protocol *inet6_protos[MAX_INET_PROTOS];
  29static DEFINE_SPINLOCK(inet6_proto_lock);
  30
  31
  32int inet6_add_protocol(const struct inet6_protocol *prot, unsigned char protocol)
  33{
  34        int ret, hash = protocol & (MAX_INET_PROTOS - 1);
  35
  36        spin_lock_bh(&inet6_proto_lock);
  37
  38        if (inet6_protos[hash]) {
  39                ret = -1;
  40        } else {
  41                inet6_protos[hash] = prot;
  42                ret = 0;
  43        }
  44
  45        spin_unlock_bh(&inet6_proto_lock);
  46
  47        return ret;
  48}
  49
  50EXPORT_SYMBOL(inet6_add_protocol);
  51
  52/*
  53 *      Remove a protocol from the hash tables.
  54 */
  55
  56int inet6_del_protocol(const struct inet6_protocol *prot, unsigned char protocol)
  57{
  58        int ret, hash = protocol & (MAX_INET_PROTOS - 1);
  59
  60        spin_lock_bh(&inet6_proto_lock);
  61
  62        if (inet6_protos[hash] != prot) {
  63                ret = -1;
  64        } else {
  65                inet6_protos[hash] = NULL;
  66                ret = 0;
  67        }
  68
  69        spin_unlock_bh(&inet6_proto_lock);
  70
  71        synchronize_net();
  72
  73        return ret;
  74}
  75
  76EXPORT_SYMBOL(inet6_del_protocol);
  77