xref: /openbmc/linux/include/net/ip6_tunnel.h (revision 6f52b16c5b29b89d92c0e7236f4655dc8491ad70)
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 
21 struct __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 };
40 
41 /* IPv6 tunnel */
42 struct ip6_tnl {
43 	struct ip6_tnl __rcu *next;	/* next tunnel in list */
44 	struct net_device *dev;	/* virtual device associated with tunnel */
45 	struct net *net;	/* netns for packet i/o */
46 	struct __ip6_tnl_parm parms;	/* tunnel configuration parameters */
47 	struct flowi fl;	/* flowi template for xmit */
48 	struct dst_cache dst_cache;	/* cached dst */
49 	struct gro_cells gro_cells;
50 
51 	int err_count;
52 	unsigned long err_time;
53 
54 	/* These fields used only by GRE */
55 	__u32 i_seqno;	/* The last seen seqno	*/
56 	__u32 o_seqno;	/* The last output seqno */
57 	int hlen;       /* tun_hlen + encap_hlen */
58 	int tun_hlen;	/* Precalculated header length */
59 	int encap_hlen; /* Encap header length (FOU,GUE) */
60 	struct ip_tunnel_encap encap;
61 	int mlink;
62 };
63 
64 struct ip6_tnl_encap_ops {
65 	size_t (*encap_hlen)(struct ip_tunnel_encap *e);
66 	int (*build_header)(struct sk_buff *skb, struct ip_tunnel_encap *e,
67 			    u8 *protocol, struct flowi6 *fl6);
68 };
69 
70 #ifdef CONFIG_INET
71 
72 extern const struct ip6_tnl_encap_ops __rcu *
73 		ip6tun_encaps[MAX_IPTUN_ENCAP_OPS];
74 
75 int ip6_tnl_encap_add_ops(const struct ip6_tnl_encap_ops *ops,
76 			  unsigned int num);
77 int ip6_tnl_encap_del_ops(const struct ip6_tnl_encap_ops *ops,
78 			  unsigned int num);
79 int ip6_tnl_encap_setup(struct ip6_tnl *t,
80 			struct ip_tunnel_encap *ipencap);
81 
82 static inline int ip6_encap_hlen(struct ip_tunnel_encap *e)
83 {
84 	const struct ip6_tnl_encap_ops *ops;
85 	int hlen = -EINVAL;
86 
87 	if (e->type == TUNNEL_ENCAP_NONE)
88 		return 0;
89 
90 	if (e->type >= MAX_IPTUN_ENCAP_OPS)
91 		return -EINVAL;
92 
93 	rcu_read_lock();
94 	ops = rcu_dereference(ip6tun_encaps[e->type]);
95 	if (likely(ops && ops->encap_hlen))
96 		hlen = ops->encap_hlen(e);
97 	rcu_read_unlock();
98 
99 	return hlen;
100 }
101 
102 static inline int ip6_tnl_encap(struct sk_buff *skb, struct ip6_tnl *t,
103 				u8 *protocol, struct flowi6 *fl6)
104 {
105 	const struct ip6_tnl_encap_ops *ops;
106 	int ret = -EINVAL;
107 
108 	if (t->encap.type == TUNNEL_ENCAP_NONE)
109 		return 0;
110 
111 	if (t->encap.type >= MAX_IPTUN_ENCAP_OPS)
112 		return -EINVAL;
113 
114 	rcu_read_lock();
115 	ops = rcu_dereference(ip6tun_encaps[t->encap.type]);
116 	if (likely(ops && ops->build_header))
117 		ret = ops->build_header(skb, &t->encap, protocol, fl6);
118 	rcu_read_unlock();
119 
120 	return ret;
121 }
122 
123 /* Tunnel encapsulation limit destination sub-option */
124 
125 struct ipv6_tlv_tnl_enc_lim {
126 	__u8 type;		/* type-code for option         */
127 	__u8 length;		/* option length                */
128 	__u8 encap_limit;	/* tunnel encapsulation limit   */
129 } __packed;
130 
131 int ip6_tnl_rcv_ctl(struct ip6_tnl *t, const struct in6_addr *laddr,
132 		const struct in6_addr *raddr);
133 int ip6_tnl_rcv(struct ip6_tnl *tunnel, struct sk_buff *skb,
134 		const struct tnl_ptk_info *tpi, struct metadata_dst *tun_dst,
135 		bool log_ecn_error);
136 int ip6_tnl_xmit_ctl(struct ip6_tnl *t, const struct in6_addr *laddr,
137 		     const struct in6_addr *raddr);
138 int ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev, __u8 dsfield,
139 		 struct flowi6 *fl6, int encap_limit, __u32 *pmtu, __u8 proto);
140 __u16 ip6_tnl_parse_tlv_enc_lim(struct sk_buff *skb, __u8 *raw);
141 __u32 ip6_tnl_get_cap(struct ip6_tnl *t, const struct in6_addr *laddr,
142 			     const struct in6_addr *raddr);
143 struct net *ip6_tnl_get_link_net(const struct net_device *dev);
144 int ip6_tnl_get_iflink(const struct net_device *dev);
145 int ip6_tnl_change_mtu(struct net_device *dev, int new_mtu);
146 
147 static inline void ip6tunnel_xmit(struct sock *sk, struct sk_buff *skb,
148 				  struct net_device *dev)
149 {
150 	int pkt_len, err;
151 
152 	memset(skb->cb, 0, sizeof(struct inet6_skb_parm));
153 	pkt_len = skb->len - skb_inner_network_offset(skb);
154 	err = ip6_local_out(dev_net(skb_dst(skb)->dev), sk, skb);
155 	if (unlikely(net_xmit_eval(err)))
156 		pkt_len = -1;
157 	iptunnel_xmit_stats(dev, pkt_len);
158 }
159 #endif
160 #endif
161