include/net/seg6.h

   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
  17 static 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
  25 static 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
  36 struct 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
  44 static 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
  53 extern int seg6_init(void);
  54 extern void seg6_exit(void);
  55 #ifdef CONFIG_IPV6_SEG6_LWTUNNEL
  56 extern int seg6_iptunnel_init(void);
  57 extern void seg6_iptunnel_exit(void);
  58 extern int seg6_local_init(void);
  59 extern void seg6_local_exit(void);
  60 #else
  61 static inline int seg6_iptunnel_init(void) { return 0; }
  62 static inline void seg6_iptunnel_exit(void) {}
  63 static inline int seg6_local_init(void) { return 0; }
  64 static inline void seg6_local_exit(void) {}
  65 #endif
  66
  67 extern bool seg6_validate_srh(struct ipv6_sr_hdr *srh, int len, bool reduced);
  68 extern struct ipv6_sr_hdr *seg6_get_srh(struct sk_buff *skb, int flags);
  69 extern void seg6_icmp_srh(struct sk_buff *skb, struct inet6_skb_parm *opt);
  70 extern int seg6_do_srh_encap(struct sk_buff *skb, struct ipv6_sr_hdr *osrh,
  71                              int proto);
  72 extern int seg6_do_srh_inline(struct sk_buff *skb, struct ipv6_sr_hdr *osrh);
  73 extern int seg6_lookup_nexthop(struct sk_buff *skb, struct in6_addr *nhaddr,
  74                                u32 tbl_id);
  75
  76 /* If the packet which invoked an ICMP error contains an SRH return
  77  * the true destination address from within the SRH, otherwise use the
  78  * destination address in the IP header.
  79  */
  80 static inline const struct in6_addr *seg6_get_daddr(struct sk_buff *skb,
  81                                                     struct inet6_skb_parm *opt)
  82 {
  83         struct ipv6_sr_hdr *srh;
  84
  85         if (opt->flags & IP6SKB_SEG6) {
  86                 srh = (struct ipv6_sr_hdr *)(skb->data + opt->srhoff);
  87                 return  &srh->segments[0];
  88         }
  89
  90         return NULL;
  91 }
  92
  93
  94 #endif