1/* SPDX-License-Identifier: GPL-2.0-or-later */
2/*
3 *  SR-IPv6 implementation
4 *
5 *  Author:
6 *  David Lebrun <david.lebrun@uclouvain.be>
7 */
8
9#ifndef _NET_SEG6_H
10#define _NET_SEG6_H
11
12#include <linux/net.h>
13#include <linux/ipv6.h>
14#include <linux/seg6.h>
15#include <linux/rhashtable-types.h>
16
17static inline void update_csum_diff4(struct sk_buff *skb, __be32 from,
18				     __be32 to)
19{
20	__be32 diff[] = { ~from, to };
21
22	skb->csum = ~csum_partial((char *)diff, sizeof(diff), ~skb->csum);
23}
24
25static inline void update_csum_diff16(struct sk_buff *skb, __be32 *from,
26				      __be32 *to)
27{
28	__be32 diff[] = {
29		~from[0], ~from[1], ~from[2], ~from[3],
30		to[0], to[1], to[2], to[3],
31	};
32
33	skb->csum = ~csum_partial((char *)diff, sizeof(diff), ~skb->csum);
34}
35
36struct seg6_pernet_data {
37	struct mutex lock;
38	struct in6_addr __rcu *tun_src;
39#ifdef CONFIG_IPV6_SEG6_HMAC
40	struct rhashtable hmac_infos;
41#endif
42};
43
44static inline struct seg6_pernet_data *seg6_pernet(struct net *net)
45{
46#if IS_ENABLED(CONFIG_IPV6)
47	return net->ipv6.seg6_data;
48#else
49	return NULL;
50#endif
51}
52
53extern int seg6_init(void);
54extern void seg6_exit(void);
55extern int seg6_iptunnel_init(void);
56extern void seg6_iptunnel_exit(void);
57extern int seg6_local_init(void);
58extern void seg6_local_exit(void);
59
60extern bool seg6_validate_srh(struct ipv6_sr_hdr *srh, int len, bool reduced);
61extern struct ipv6_sr_hdr *seg6_get_srh(struct sk_buff *skb, int flags);
62extern void seg6_icmp_srh(struct sk_buff *skb, struct inet6_skb_parm *opt);
63extern int seg6_do_srh_encap(struct sk_buff *skb, struct ipv6_sr_hdr *osrh,
64			     int proto);
65extern int seg6_do_srh_inline(struct sk_buff *skb, struct ipv6_sr_hdr *osrh);
66extern int seg6_lookup_nexthop(struct sk_buff *skb, struct in6_addr *nhaddr,
67			       u32 tbl_id);
68
69/* If the packet which invoked an ICMP error contains an SRH return
70 * the true destination address from within the SRH, otherwise use the
71 * destination address in the IP header.
72 */
73static inline const struct in6_addr *seg6_get_daddr(struct sk_buff *skb,
74						    struct inet6_skb_parm *opt)
75{
76	struct ipv6_sr_hdr *srh;
77
78	if (opt->flags & IP6SKB_SEG6) {
79		srh = (struct ipv6_sr_hdr *)(skb->data + opt->srhoff);
80		return  &srh->segments[0];
81	}
82
83	return NULL;
84}
85
86
87#endif
88