xref: /linux/net/ipv6/protocol.c (revision 6c8c1406a6d6a3f2e61ac590f5c0994231bc6be7)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * INET		An implementation of the TCP/IP protocol suite for the LINUX
4  *		operating system.  INET is implemented using the  BSD Socket
5  *		interface as the means of communication with the user level.
6  *
7  *		PF_INET6 protocol dispatch tables.
8  *
9  * Authors:	Pedro Roque	<roque@di.fc.ul.pt>
10  */
11 
12 /*
13  *      Changes:
14  *
15  *      Vince Laviano (vince@cs.stanford.edu)       16 May 2001
16  *      - Removed unused variable 'inet6_protocol_base'
17  *      - Modified inet6_del_protocol() to correctly maintain copy bit.
18  */
19 #include <linux/module.h>
20 #include <linux/netdevice.h>
21 #include <linux/spinlock.h>
22 #include <net/protocol.h>
23 
24 #if IS_ENABLED(CONFIG_IPV6)
25 struct inet6_protocol __rcu *inet6_protos[MAX_INET_PROTOS] __read_mostly;
26 EXPORT_SYMBOL(inet6_protos);
27 
28 int inet6_add_protocol(const struct inet6_protocol *prot, unsigned char protocol)
29 {
30 	return !cmpxchg((const struct inet6_protocol **)&inet6_protos[protocol],
31 			NULL, prot) ? 0 : -1;
32 }
33 EXPORT_SYMBOL(inet6_add_protocol);
34 
35 int inet6_del_protocol(const struct inet6_protocol *prot, unsigned char protocol)
36 {
37 	int ret;
38 
39 	ret = (cmpxchg((const struct inet6_protocol **)&inet6_protos[protocol],
40 		       prot, NULL) == prot) ? 0 : -1;
41 
42 	synchronize_net();
43 
44 	return ret;
45 }
46 EXPORT_SYMBOL(inet6_del_protocol);
47 #endif
48 
49 const struct net_offload __rcu *inet6_offloads[MAX_INET_PROTOS] __read_mostly;
50 EXPORT_SYMBOL(inet6_offloads);
51 
52 int inet6_add_offload(const struct net_offload *prot, unsigned char protocol)
53 {
54 	return !cmpxchg((const struct net_offload **)&inet6_offloads[protocol],
55 			NULL, prot) ? 0 : -1;
56 }
57 EXPORT_SYMBOL(inet6_add_offload);
58 
59 int inet6_del_offload(const struct net_offload *prot, unsigned char protocol)
60 {
61 	int ret;
62 
63 	ret = (cmpxchg((const struct net_offload **)&inet6_offloads[protocol],
64 		       prot, NULL) == prot) ? 0 : -1;
65 
66 	synchronize_net();
67 
68 	return ret;
69 }
70 EXPORT_SYMBOL(inet6_del_offload);
71