1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __NET_LWTUNNEL_H
3 #define __NET_LWTUNNEL_H 1
5 #include <linux/lwtunnel.h>
6 #include <linux/netdevice.h>
7 #include <linux/skbuff.h>
8 #include <linux/types.h>
11 #define LWTUNNEL_HASH_BITS 7
12 #define LWTUNNEL_HASH_SIZE (1 << LWTUNNEL_HASH_BITS)
14 /* lw tunnel state flags */
15 #define LWTUNNEL_STATE_OUTPUT_REDIRECT BIT(0)
16 #define LWTUNNEL_STATE_INPUT_REDIRECT BIT(1)
17 #define LWTUNNEL_STATE_XMIT_REDIRECT BIT(2)
21 LWTUNNEL_XMIT_CONTINUE,
25 struct lwtunnel_state {
30 int (*orig_output)(struct net *net, struct sock *sk, struct sk_buff *skb);
31 int (*orig_input)(struct sk_buff *);
36 struct lwtunnel_encap_ops {
37 int (*build_state)(struct net *net, struct nlattr *encap,
38 unsigned int family, const void *cfg,
39 struct lwtunnel_state **ts,
40 struct netlink_ext_ack *extack);
41 void (*destroy_state)(struct lwtunnel_state *lws);
42 int (*output)(struct net *net, struct sock *sk, struct sk_buff *skb);
43 int (*input)(struct sk_buff *skb);
44 int (*fill_encap)(struct sk_buff *skb,
45 struct lwtunnel_state *lwtstate);
46 int (*get_encap_size)(struct lwtunnel_state *lwtstate);
47 int (*cmp_encap)(struct lwtunnel_state *a, struct lwtunnel_state *b);
48 int (*xmit)(struct sk_buff *skb);
53 #ifdef CONFIG_LWTUNNEL
55 DECLARE_STATIC_KEY_FALSE(nf_hooks_lwtunnel_enabled);
57 void lwtstate_free(struct lwtunnel_state *lws);
59 static inline struct lwtunnel_state *
60 lwtstate_get(struct lwtunnel_state *lws)
63 atomic_inc(&lws->refcnt);
68 static inline void lwtstate_put(struct lwtunnel_state *lws)
73 if (atomic_dec_and_test(&lws->refcnt))
77 static inline bool lwtunnel_output_redirect(struct lwtunnel_state *lwtstate)
79 if (lwtstate && (lwtstate->flags & LWTUNNEL_STATE_OUTPUT_REDIRECT))
85 static inline bool lwtunnel_input_redirect(struct lwtunnel_state *lwtstate)
87 if (lwtstate && (lwtstate->flags & LWTUNNEL_STATE_INPUT_REDIRECT))
93 static inline bool lwtunnel_xmit_redirect(struct lwtunnel_state *lwtstate)
95 if (lwtstate && (lwtstate->flags & LWTUNNEL_STATE_XMIT_REDIRECT))
101 static inline unsigned int lwtunnel_headroom(struct lwtunnel_state *lwtstate,
104 if ((lwtunnel_xmit_redirect(lwtstate) ||
105 lwtunnel_output_redirect(lwtstate)) && lwtstate->headroom < mtu)
106 return lwtstate->headroom;
111 int lwtunnel_encap_add_ops(const struct lwtunnel_encap_ops *op,
113 int lwtunnel_encap_del_ops(const struct lwtunnel_encap_ops *op,
115 int lwtunnel_valid_encap_type(u16 encap_type,
116 struct netlink_ext_ack *extack);
117 int lwtunnel_valid_encap_type_attr(struct nlattr *attr, int len,
118 struct netlink_ext_ack *extack);
119 int lwtunnel_build_state(struct net *net, u16 encap_type,
120 struct nlattr *encap,
121 unsigned int family, const void *cfg,
122 struct lwtunnel_state **lws,
123 struct netlink_ext_ack *extack);
124 int lwtunnel_fill_encap(struct sk_buff *skb, struct lwtunnel_state *lwtstate,
125 int encap_attr, int encap_type_attr);
126 int lwtunnel_get_encap_size(struct lwtunnel_state *lwtstate);
127 struct lwtunnel_state *lwtunnel_state_alloc(int hdr_len);
128 int lwtunnel_cmp_encap(struct lwtunnel_state *a, struct lwtunnel_state *b);
129 int lwtunnel_output(struct net *net, struct sock *sk, struct sk_buff *skb);
130 int lwtunnel_input(struct sk_buff *skb);
131 int lwtunnel_xmit(struct sk_buff *skb);
132 int bpf_lwt_push_ip_encap(struct sk_buff *skb, void *hdr, u32 len,
135 static inline void lwtunnel_set_redirect(struct dst_entry *dst)
137 if (lwtunnel_output_redirect(dst->lwtstate)) {
138 dst->lwtstate->orig_output = dst->output;
139 dst->output = lwtunnel_output;
141 if (lwtunnel_input_redirect(dst->lwtstate)) {
142 dst->lwtstate->orig_input = dst->input;
143 dst->input = lwtunnel_input;
148 static inline void lwtstate_free(struct lwtunnel_state *lws)
152 static inline struct lwtunnel_state *
153 lwtstate_get(struct lwtunnel_state *lws)
158 static inline void lwtstate_put(struct lwtunnel_state *lws)
162 static inline bool lwtunnel_output_redirect(struct lwtunnel_state *lwtstate)
167 static inline bool lwtunnel_input_redirect(struct lwtunnel_state *lwtstate)
172 static inline bool lwtunnel_xmit_redirect(struct lwtunnel_state *lwtstate)
177 static inline void lwtunnel_set_redirect(struct dst_entry *dst)
181 static inline unsigned int lwtunnel_headroom(struct lwtunnel_state *lwtstate,
187 static inline int lwtunnel_encap_add_ops(const struct lwtunnel_encap_ops *op,
194 static inline int lwtunnel_encap_del_ops(const struct lwtunnel_encap_ops *op,
200 static inline int lwtunnel_valid_encap_type(u16 encap_type,
201 struct netlink_ext_ack *extack)
203 NL_SET_ERR_MSG(extack, "CONFIG_LWTUNNEL is not enabled in this kernel");
206 static inline int lwtunnel_valid_encap_type_attr(struct nlattr *attr, int len,
207 struct netlink_ext_ack *extack)
209 /* return 0 since we are not walking attr looking for
210 * RTA_ENCAP_TYPE attribute on nexthops.
215 static inline int lwtunnel_build_state(struct net *net, u16 encap_type,
216 struct nlattr *encap,
217 unsigned int family, const void *cfg,
218 struct lwtunnel_state **lws,
219 struct netlink_ext_ack *extack)
224 static inline int lwtunnel_fill_encap(struct sk_buff *skb,
225 struct lwtunnel_state *lwtstate,
226 int encap_attr, int encap_type_attr)
231 static inline int lwtunnel_get_encap_size(struct lwtunnel_state *lwtstate)
236 static inline struct lwtunnel_state *lwtunnel_state_alloc(int hdr_len)
241 static inline int lwtunnel_cmp_encap(struct lwtunnel_state *a,
242 struct lwtunnel_state *b)
247 static inline int lwtunnel_output(struct net *net, struct sock *sk, struct sk_buff *skb)
252 static inline int lwtunnel_input(struct sk_buff *skb)
257 static inline int lwtunnel_xmit(struct sk_buff *skb)
262 #endif /* CONFIG_LWTUNNEL */
264 #define MODULE_ALIAS_RTNL_LWT(encap_type) MODULE_ALIAS("rtnl-lwt-" __stringify(encap_type))
266 #endif /* __NET_LWTUNNEL_H */