xref: /linux-6.15/include/linux/ipv6.h (revision 6ea76f33)
1 #ifndef _IPV6_H
2 #define _IPV6_H
3 
4 #include <uapi/linux/ipv6.h>
5 
6 #define ipv6_optlen(p)  (((p)->hdrlen+1) << 3)
7 #define ipv6_authlen(p) (((p)->hdrlen+2) << 2)
8 /*
9  * This structure contains configuration options per IPv6 link.
10  */
11 struct ipv6_devconf {
12 	__s32		forwarding;
13 	__s32		hop_limit;
14 	__s32		mtu6;
15 	__s32		accept_ra;
16 	__s32		accept_redirects;
17 	__s32		autoconf;
18 	__s32		dad_transmits;
19 	__s32		rtr_solicits;
20 	__s32		rtr_solicit_interval;
21 	__s32		rtr_solicit_max_interval;
22 	__s32		rtr_solicit_delay;
23 	__s32		force_mld_version;
24 	__s32		mldv1_unsolicited_report_interval;
25 	__s32		mldv2_unsolicited_report_interval;
26 	__s32		use_tempaddr;
27 	__s32		temp_valid_lft;
28 	__s32		temp_prefered_lft;
29 	__s32		regen_max_retry;
30 	__s32		max_desync_factor;
31 	__s32		max_addresses;
32 	__s32		accept_ra_defrtr;
33 	__s32		accept_ra_min_hop_limit;
34 	__s32		accept_ra_pinfo;
35 	__s32		ignore_routes_with_linkdown;
36 #ifdef CONFIG_IPV6_ROUTER_PREF
37 	__s32		accept_ra_rtr_pref;
38 	__s32		rtr_probe_interval;
39 #ifdef CONFIG_IPV6_ROUTE_INFO
40 	__s32		accept_ra_rt_info_max_plen;
41 #endif
42 #endif
43 	__s32		proxy_ndp;
44 	__s32		accept_source_route;
45 	__s32		accept_ra_from_local;
46 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
47 	__s32		optimistic_dad;
48 	__s32		use_optimistic;
49 #endif
50 #ifdef CONFIG_IPV6_MROUTE
51 	__s32		mc_forwarding;
52 #endif
53 	__s32		disable_ipv6;
54 	__s32		drop_unicast_in_l2_multicast;
55 	__s32		accept_dad;
56 	__s32		force_tllao;
57 	__s32           ndisc_notify;
58 	__s32		suppress_frag_ndisc;
59 	__s32		accept_ra_mtu;
60 	__s32		drop_unsolicited_na;
61 	struct ipv6_stable_secret {
62 		bool initialized;
63 		struct in6_addr secret;
64 	} stable_secret;
65 	__s32		use_oif_addrs_only;
66 	__s32		keep_addr_on_down;
67 
68 	struct ctl_table_header *sysctl_header;
69 };
70 
71 struct ipv6_params {
72 	__s32 disable_ipv6;
73 	__s32 autoconf;
74 };
75 extern struct ipv6_params ipv6_defaults;
76 #include <linux/icmpv6.h>
77 #include <linux/tcp.h>
78 #include <linux/udp.h>
79 
80 #include <net/inet_sock.h>
81 
82 static inline struct ipv6hdr *ipv6_hdr(const struct sk_buff *skb)
83 {
84 	return (struct ipv6hdr *)skb_network_header(skb);
85 }
86 
87 static inline struct ipv6hdr *inner_ipv6_hdr(const struct sk_buff *skb)
88 {
89 	return (struct ipv6hdr *)skb_inner_network_header(skb);
90 }
91 
92 static inline struct ipv6hdr *ipipv6_hdr(const struct sk_buff *skb)
93 {
94 	return (struct ipv6hdr *)skb_transport_header(skb);
95 }
96 
97 /*
98    This structure contains results of exthdrs parsing
99    as offsets from skb->nh.
100  */
101 
102 struct inet6_skb_parm {
103 	int			iif;
104 	__be16			ra;
105 	__u16			dst0;
106 	__u16			srcrt;
107 	__u16			dst1;
108 	__u16			lastopt;
109 	__u16			nhoff;
110 	__u16			flags;
111 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
112 	__u16			dsthao;
113 #endif
114 	__u16			frag_max_size;
115 
116 #define IP6SKB_XFRM_TRANSFORMED	1
117 #define IP6SKB_FORWARDED	2
118 #define IP6SKB_REROUTED		4
119 #define IP6SKB_ROUTERALERT	8
120 #define IP6SKB_FRAGMENTED      16
121 #define IP6SKB_HOPBYHOP        32
122 #define IP6SKB_L3SLAVE         64
123 };
124 
125 #if defined(CONFIG_NET_L3_MASTER_DEV)
126 static inline bool skb_l3mdev_slave(__u16 flags)
127 {
128 	return flags & IP6SKB_L3SLAVE;
129 }
130 #else
131 static inline bool skb_l3mdev_slave(__u16 flags)
132 {
133 	return false;
134 }
135 #endif
136 
137 #define IP6CB(skb)	((struct inet6_skb_parm*)((skb)->cb))
138 #define IP6CBMTU(skb)	((struct ip6_mtuinfo *)((skb)->cb))
139 
140 static inline int inet6_iif(const struct sk_buff *skb)
141 {
142 	bool l3_slave = skb_l3mdev_slave(IP6CB(skb)->flags);
143 
144 	return l3_slave ? skb->skb_iif : IP6CB(skb)->iif;
145 }
146 
147 struct tcp6_request_sock {
148 	struct tcp_request_sock	  tcp6rsk_tcp;
149 };
150 
151 struct ipv6_mc_socklist;
152 struct ipv6_ac_socklist;
153 struct ipv6_fl_socklist;
154 
155 struct inet6_cork {
156 	struct ipv6_txoptions *opt;
157 	u8 hop_limit;
158 	u8 tclass;
159 };
160 
161 /**
162  * struct ipv6_pinfo - ipv6 private area
163  *
164  * In the struct sock hierarchy (tcp6_sock, upd6_sock, etc)
165  * this _must_ be the last member, so that inet6_sk_generic
166  * is able to calculate its offset from the base struct sock
167  * by using the struct proto->slab_obj_size member. -acme
168  */
169 struct ipv6_pinfo {
170 	struct in6_addr 	saddr;
171 	struct in6_pktinfo	sticky_pktinfo;
172 	const struct in6_addr		*daddr_cache;
173 #ifdef CONFIG_IPV6_SUBTREES
174 	const struct in6_addr		*saddr_cache;
175 #endif
176 
177 	__be32			flow_label;
178 	__u32			frag_size;
179 
180 	/*
181 	 * Packed in 16bits.
182 	 * Omit one shift by by putting the signed field at MSB.
183 	 */
184 #if defined(__BIG_ENDIAN_BITFIELD)
185 	__s16			hop_limit:9;
186 	__u16			__unused_1:7;
187 #else
188 	__u16			__unused_1:7;
189 	__s16			hop_limit:9;
190 #endif
191 
192 #if defined(__BIG_ENDIAN_BITFIELD)
193 	/* Packed in 16bits. */
194 	__s16			mcast_hops:9;
195 	__u16			__unused_2:6,
196 				mc_loop:1;
197 #else
198 	__u16			mc_loop:1,
199 				__unused_2:6;
200 	__s16			mcast_hops:9;
201 #endif
202 	int			ucast_oif;
203 	int			mcast_oif;
204 
205 	/* pktoption flags */
206 	union {
207 		struct {
208 			__u16	srcrt:1,
209 				osrcrt:1,
210 			        rxinfo:1,
211 			        rxoinfo:1,
212 				rxhlim:1,
213 				rxohlim:1,
214 				hopopts:1,
215 				ohopopts:1,
216 				dstopts:1,
217 				odstopts:1,
218                                 rxflow:1,
219 				rxtclass:1,
220 				rxpmtu:1,
221 				rxorigdstaddr:1;
222 				/* 2 bits hole */
223 		} bits;
224 		__u16		all;
225 	} rxopt;
226 
227 	/* sockopt flags */
228 	__u16			recverr:1,
229 	                        sndflow:1,
230 				repflow:1,
231 				pmtudisc:3,
232 				padding:1,	/* 1 bit hole */
233 				srcprefs:3,	/* 001: prefer temporary address
234 						 * 010: prefer public address
235 						 * 100: prefer care-of address
236 						 */
237 				dontfrag:1,
238 				autoflowlabel:1;
239 	__u8			min_hopcount;
240 	__u8			tclass;
241 	__be32			rcv_flowinfo;
242 
243 	__u32			dst_cookie;
244 	__u32			rx_dst_cookie;
245 
246 	struct ipv6_mc_socklist	__rcu *ipv6_mc_list;
247 	struct ipv6_ac_socklist	*ipv6_ac_list;
248 	struct ipv6_fl_socklist __rcu *ipv6_fl_list;
249 
250 	struct ipv6_txoptions __rcu	*opt;
251 	struct sk_buff		*pktoptions;
252 	struct sk_buff		*rxpmtu;
253 	struct inet6_cork	cork;
254 };
255 
256 /* WARNING: don't change the layout of the members in {raw,udp,tcp}6_sock! */
257 struct raw6_sock {
258 	/* inet_sock has to be the first member of raw6_sock */
259 	struct inet_sock	inet;
260 	__u32			checksum;	/* perform checksum */
261 	__u32			offset;		/* checksum offset  */
262 	struct icmp6_filter	filter;
263 	__u32			ip6mr_table;
264 	/* ipv6_pinfo has to be the last member of raw6_sock, see inet6_sk_generic */
265 	struct ipv6_pinfo	inet6;
266 };
267 
268 struct udp6_sock {
269 	struct udp_sock	  udp;
270 	/* ipv6_pinfo has to be the last member of udp6_sock, see inet6_sk_generic */
271 	struct ipv6_pinfo inet6;
272 };
273 
274 struct tcp6_sock {
275 	struct tcp_sock	  tcp;
276 	/* ipv6_pinfo has to be the last member of tcp6_sock, see inet6_sk_generic */
277 	struct ipv6_pinfo inet6;
278 };
279 
280 extern int inet6_sk_rebuild_header(struct sock *sk);
281 
282 struct tcp6_timewait_sock {
283 	struct tcp_timewait_sock   tcp6tw_tcp;
284 };
285 
286 #if IS_ENABLED(CONFIG_IPV6)
287 bool ipv6_mod_enabled(void);
288 
289 static inline struct ipv6_pinfo *inet6_sk(const struct sock *__sk)
290 {
291 	return sk_fullsock(__sk) ? inet_sk(__sk)->pinet6 : NULL;
292 }
293 
294 static inline struct raw6_sock *raw6_sk(const struct sock *sk)
295 {
296 	return (struct raw6_sock *)sk;
297 }
298 
299 static inline void inet_sk_copy_descendant(struct sock *sk_to,
300 					   const struct sock *sk_from)
301 {
302 	int ancestor_size = sizeof(struct inet_sock);
303 
304 	if (sk_from->sk_family == PF_INET6)
305 		ancestor_size += sizeof(struct ipv6_pinfo);
306 
307 	__inet_sk_copy_descendant(sk_to, sk_from, ancestor_size);
308 }
309 
310 #define __ipv6_only_sock(sk)	(sk->sk_ipv6only)
311 #define ipv6_only_sock(sk)	(__ipv6_only_sock(sk))
312 #define ipv6_sk_rxinfo(sk)	((sk)->sk_family == PF_INET6 && \
313 				 inet6_sk(sk)->rxopt.bits.rxinfo)
314 
315 static inline const struct in6_addr *inet6_rcv_saddr(const struct sock *sk)
316 {
317 	if (sk->sk_family == AF_INET6)
318 		return &sk->sk_v6_rcv_saddr;
319 	return NULL;
320 }
321 
322 static inline int inet_v6_ipv6only(const struct sock *sk)
323 {
324 	/* ipv6only field is at same position for timewait and other sockets */
325 	return ipv6_only_sock(sk);
326 }
327 #else
328 #define __ipv6_only_sock(sk)	0
329 #define ipv6_only_sock(sk)	0
330 #define ipv6_sk_rxinfo(sk)	0
331 
332 static inline bool ipv6_mod_enabled(void)
333 {
334 	return false;
335 }
336 
337 static inline struct ipv6_pinfo * inet6_sk(const struct sock *__sk)
338 {
339 	return NULL;
340 }
341 
342 static inline struct inet6_request_sock *
343 			inet6_rsk(const struct request_sock *rsk)
344 {
345 	return NULL;
346 }
347 
348 static inline struct raw6_sock *raw6_sk(const struct sock *sk)
349 {
350 	return NULL;
351 }
352 
353 #define inet6_rcv_saddr(__sk)	NULL
354 #define tcp_twsk_ipv6only(__sk)		0
355 #define inet_v6_ipv6only(__sk)		0
356 #endif /* IS_ENABLED(CONFIG_IPV6) */
357 #endif /* _IPV6_H */
358