blob: 90a587cacaa4bbb6fabb04fae60745431031ff8c [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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 * INET protocol dispatch tables.
7 *
8 * Version: $Id: protocol.c,v 1.14 2001/05/18 02:25:49 davem Exp $
9 *
10 * Authors: Ross Biro, <bir7@leland.Stanford.Edu>
11 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
12 *
13 * Fixes:
14 * Alan Cox : Ahah! udp icmp errors don't work because
15 * udp_err is never called!
16 * Alan Cox : Added new fields for init and ready for
17 * proper fragmentation (_NO_ 4K limits!)
18 * Richard Colella : Hang on hash collision
19 * Vince Laviano : Modified inet_del_protocol() to correctly
20 * maintain copy bit.
21 *
22 * This program is free software; you can redistribute it and/or
23 * modify it under the terms of the GNU General Public License
24 * as published by the Free Software Foundation; either version
25 * 2 of the License, or (at your option) any later version.
26 */
27
28#include <asm/uaccess.h>
29#include <asm/system.h>
30#include <linux/module.h>
31#include <linux/types.h>
32#include <linux/kernel.h>
33#include <linux/sched.h>
34#include <linux/string.h>
35#include <linux/config.h>
36#include <linux/socket.h>
37#include <linux/in.h>
38#include <linux/inet.h>
39#include <linux/netdevice.h>
40#include <linux/timer.h>
41#include <net/ip.h>
42#include <net/protocol.h>
43#include <net/tcp.h>
44#include <linux/skbuff.h>
45#include <net/sock.h>
46#include <net/icmp.h>
47#include <net/udp.h>
48#include <net/ipip.h>
49#include <linux/igmp.h>
50
51struct net_protocol *inet_protos[MAX_INET_PROTOS];
52static DEFINE_SPINLOCK(inet_proto_lock);
53
54/*
55 * Add a protocol handler to the hash tables
56 */
57
58int inet_add_protocol(struct net_protocol *prot, unsigned char protocol)
59{
60 int hash, ret;
61
62 hash = protocol & (MAX_INET_PROTOS - 1);
63
64 spin_lock_bh(&inet_proto_lock);
65 if (inet_protos[hash]) {
66 ret = -1;
67 } else {
68 inet_protos[hash] = prot;
69 ret = 0;
70 }
71 spin_unlock_bh(&inet_proto_lock);
72
73 return ret;
74}
75
76/*
77 * Remove a protocol from the hash tables.
78 */
79
80int inet_del_protocol(struct net_protocol *prot, unsigned char protocol)
81{
82 int hash, ret;
83
84 hash = protocol & (MAX_INET_PROTOS - 1);
85
86 spin_lock_bh(&inet_proto_lock);
87 if (inet_protos[hash] == prot) {
88 inet_protos[hash] = NULL;
89 ret = 0;
90 } else {
91 ret = -1;
92 }
93 spin_unlock_bh(&inet_proto_lock);
94
95 synchronize_net();
96
97 return ret;
98}
99
100EXPORT_SYMBOL(inet_add_protocol);
101EXPORT_SYMBOL(inet_del_protocol);