1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _NET_IP6_TUNNEL_H
3#define _NET_IP6_TUNNEL_H
4
5#include <linux/ipv6.h>
6#include <linux/netdevice.h>
7#include <linux/if_tunnel.h>
8#include <linux/ip6_tunnel.h>
9#include <net/ip_tunnels.h>
10#include <net/dst_cache.h>
11
12#define IP6TUNNEL_ERR_TIMEO (30*HZ)
13
14/* capable of sending packets */
15#define IP6_TNL_F_CAP_XMIT 0x10000
16/* capable of receiving packets */
17#define IP6_TNL_F_CAP_RCV 0x20000
18/* determine capability on a per-packet basis */
19#define IP6_TNL_F_CAP_PER_PACKET 0x40000
20
21struct __ip6_tnl_parm {
22 char name[IFNAMSIZ]; /* name of tunnel device */
23 int link; /* ifindex of underlying L2 interface */
24 __u8 proto; /* tunnel protocol */
25 __u8 encap_limit; /* encapsulation limit for tunnel */
26 __u8 hop_limit; /* hop limit for tunnel */
27 bool collect_md;
28 __be32 flowinfo; /* traffic class and flowlabel for tunnel */
29 __u32 flags; /* tunnel flags */
30 struct in6_addr laddr; /* local tunnel end-point address */
31 struct in6_addr raddr; /* remote tunnel end-point address */
32
33 __be16 i_flags;
34 __be16 o_flags;
35 __be32 i_key;
36 __be32 o_key;
37
38 __u32 fwmark;
39 __u32 index; /* ERSPAN type II index */
40 __u8 erspan_ver; /* ERSPAN version */
41 __u8 dir; /* direction */
42 __u16 hwid; /* hwid */
43};
44
45/* IPv6 tunnel */
46struct ip6_tnl {
47 struct ip6_tnl __rcu *next; /* next tunnel in list */
48 struct net_device *dev; /* virtual device associated with tunnel */
49 netdevice_tracker dev_tracker;
50 struct net *net; /* netns for packet i/o */
51 struct __ip6_tnl_parm parms; /* tunnel configuration parameters */
52 struct flowi fl; /* flowi template for xmit */
53 struct dst_cache dst_cache; /* cached dst */
54 struct gro_cells gro_cells;
55
56 int err_count;
57 unsigned long err_time;
58
59 /* These fields used only by GRE */
60 __u32 i_seqno; /* The last seen seqno */
61 atomic_t o_seqno; /* The last output seqno */
62 int hlen; /* tun_hlen + encap_hlen */
63 int tun_hlen; /* Precalculated header length */
64 int encap_hlen; /* Encap header length (FOU,GUE) */
65 struct ip_tunnel_encap encap;
66 int mlink;
67};
68
69struct ip6_tnl_encap_ops {
70 size_t (*encap_hlen)(struct ip_tunnel_encap *e);
71 int (*build_header)(struct sk_buff *skb, struct ip_tunnel_encap *e,
72 u8 *protocol, struct flowi6 *fl6);
73 int (*err_handler)(struct sk_buff *skb, struct inet6_skb_parm *opt,
74 u8 type, u8 code, int offset, __be32 info);
75};
76
77#ifdef CONFIG_INET
78
79extern const struct ip6_tnl_encap_ops __rcu *
80 ip6tun_encaps[MAX_IPTUN_ENCAP_OPS];
81
82int ip6_tnl_encap_add_ops(const struct ip6_tnl_encap_ops *ops,
83 unsigned int num);
84int ip6_tnl_encap_del_ops(const struct ip6_tnl_encap_ops *ops,
85 unsigned int num);
86int ip6_tnl_encap_setup(struct ip6_tnl *t,
87 struct ip_tunnel_encap *ipencap);
88
89static inline int ip6_encap_hlen(struct ip_tunnel_encap *e)
90{
91 const struct ip6_tnl_encap_ops *ops;
92 int hlen = -EINVAL;
93
94 if (e->type == TUNNEL_ENCAP_NONE)
95 return 0;
96
97 if (e->type >= MAX_IPTUN_ENCAP_OPS)
98 return -EINVAL;
99
100 rcu_read_lock();
101 ops = rcu_dereference(ip6tun_encaps[e->type]);
102 if (likely(ops && ops->encap_hlen))
103 hlen = ops->encap_hlen(e);
104 rcu_read_unlock();
105
106 return hlen;
107}
108
109static inline int ip6_tnl_encap(struct sk_buff *skb, struct ip6_tnl *t,
110 u8 *protocol, struct flowi6 *fl6)
111{
112 const struct ip6_tnl_encap_ops *ops;
113 int ret = -EINVAL;
114
115 if (t->encap.type == TUNNEL_ENCAP_NONE)
116 return 0;
117
118 if (t->encap.type >= MAX_IPTUN_ENCAP_OPS)
119 return -EINVAL;
120
121 rcu_read_lock();
122 ops = rcu_dereference(ip6tun_encaps[t->encap.type]);
123 if (likely(ops && ops->build_header))
124 ret = ops->build_header(skb, &t->encap, protocol, fl6);
125 rcu_read_unlock();
126
127 return ret;
128}
129
130/* Tunnel encapsulation limit destination sub-option */
131
132struct ipv6_tlv_tnl_enc_lim {
133 __u8 type; /* type-code for option */
134 __u8 length; /* option length */
135 __u8 encap_limit; /* tunnel encapsulation limit */
136} __packed;
137
138int ip6_tnl_rcv_ctl(struct ip6_tnl *t, const struct in6_addr *laddr,
139 const struct in6_addr *raddr);
140int ip6_tnl_rcv(struct ip6_tnl *tunnel, struct sk_buff *skb,
141 const struct tnl_ptk_info *tpi, struct metadata_dst *tun_dst,
142 bool log_ecn_error);
143int ip6_tnl_xmit_ctl(struct ip6_tnl *t, const struct in6_addr *laddr,
144 const struct in6_addr *raddr);
145int ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev, __u8 dsfield,
146 struct flowi6 *fl6, int encap_limit, __u32 *pmtu, __u8 proto);
147__u16 ip6_tnl_parse_tlv_enc_lim(struct sk_buff *skb, __u8 *raw);
148__u32 ip6_tnl_get_cap(struct ip6_tnl *t, const struct in6_addr *laddr,
149 const struct in6_addr *raddr);
150struct net *ip6_tnl_get_link_net(const struct net_device *dev);
151int ip6_tnl_get_iflink(const struct net_device *dev);
152int ip6_tnl_change_mtu(struct net_device *dev, int new_mtu);
153
154static inline void ip6tunnel_xmit(struct sock *sk, struct sk_buff *skb,
155 struct net_device *dev)
156{
157 int pkt_len, err;
158
159 memset(skb->cb, 0, sizeof(struct inet6_skb_parm));
160 pkt_len = skb->len - skb_inner_network_offset(skb);
161 err = ip6_local_out(net: dev_net(dev: skb_dst(skb)->dev), sk, skb);
162
163 if (dev) {
164 if (unlikely(net_xmit_eval(err)))
165 pkt_len = -1;
166 iptunnel_xmit_stats(dev, pkt_len);
167 }
168}
169#endif
170#endif
171

source code of linux/include/net/ip6_tunnel.h