xref: /linux-6.15/include/linux/ipv6.h (revision 2b8232ce)
1 #ifndef _IPV6_H
2 #define _IPV6_H
3 
4 #include <linux/in6.h>
5 #include <asm/byteorder.h>
6 
7 /* The latest drafts declared increase in minimal mtu up to 1280. */
8 
9 #define IPV6_MIN_MTU	1280
10 
11 /*
12  *	Advanced API
13  *	source interface/address selection, source routing, etc...
14  *	*under construction*
15  */
16 
17 
18 struct in6_pktinfo {
19 	struct in6_addr	ipi6_addr;
20 	int		ipi6_ifindex;
21 };
22 
23 
24 struct in6_ifreq {
25 	struct in6_addr	ifr6_addr;
26 	__u32		ifr6_prefixlen;
27 	int		ifr6_ifindex;
28 };
29 
30 #define IPV6_SRCRT_STRICT	0x01	/* Deprecated; will be removed */
31 #define IPV6_SRCRT_TYPE_0	0	/* Deprecated; will be removed */
32 #define IPV6_SRCRT_TYPE_2	2	/* IPv6 type 2 Routing Header	*/
33 
34 /*
35  *	routing header
36  */
37 struct ipv6_rt_hdr {
38 	__u8		nexthdr;
39 	__u8		hdrlen;
40 	__u8		type;
41 	__u8		segments_left;
42 
43 	/*
44 	 *	type specific data
45 	 *	variable length field
46 	 */
47 };
48 
49 
50 struct ipv6_opt_hdr {
51 	__u8 		nexthdr;
52 	__u8 		hdrlen;
53 	/*
54 	 * TLV encoded option data follows.
55 	 */
56 };
57 
58 #define ipv6_destopt_hdr ipv6_opt_hdr
59 #define ipv6_hopopt_hdr  ipv6_opt_hdr
60 
61 #ifdef __KERNEL__
62 #define ipv6_optlen(p)  (((p)->hdrlen+1) << 3)
63 #endif
64 
65 /*
66  *	routing header type 0 (used in cmsghdr struct)
67  */
68 
69 struct rt0_hdr {
70 	struct ipv6_rt_hdr	rt_hdr;
71 	__u32			reserved;
72 	struct in6_addr		addr[0];
73 
74 #define rt0_type		rt_hdr.type
75 };
76 
77 /*
78  *	routing header type 2
79  */
80 
81 struct rt2_hdr {
82 	struct ipv6_rt_hdr	rt_hdr;
83 	__u32			reserved;
84 	struct in6_addr		addr;
85 
86 #define rt2_type		rt_hdr.type
87 };
88 
89 /*
90  *	home address option in destination options header
91  */
92 
93 struct ipv6_destopt_hao {
94 	__u8			type;
95 	__u8			length;
96 	struct in6_addr		addr;
97 } __attribute__ ((__packed__));
98 
99 /*
100  *	IPv6 fixed header
101  *
102  *	BEWARE, it is incorrect. The first 4 bits of flow_lbl
103  *	are glued to priority now, forming "class".
104  */
105 
106 struct ipv6hdr {
107 #if defined(__LITTLE_ENDIAN_BITFIELD)
108 	__u8			priority:4,
109 				version:4;
110 #elif defined(__BIG_ENDIAN_BITFIELD)
111 	__u8			version:4,
112 				priority:4;
113 #else
114 #error	"Please fix <asm/byteorder.h>"
115 #endif
116 	__u8			flow_lbl[3];
117 
118 	__be16			payload_len;
119 	__u8			nexthdr;
120 	__u8			hop_limit;
121 
122 	struct	in6_addr	saddr;
123 	struct	in6_addr	daddr;
124 };
125 
126 /*
127  * This structure contains configuration options per IPv6 link.
128  */
129 struct ipv6_devconf {
130 	__s32		forwarding;
131 	__s32		hop_limit;
132 	__s32		mtu6;
133 	__s32		accept_ra;
134 	__s32		accept_redirects;
135 	__s32		autoconf;
136 	__s32		dad_transmits;
137 	__s32		rtr_solicits;
138 	__s32		rtr_solicit_interval;
139 	__s32		rtr_solicit_delay;
140 	__s32		force_mld_version;
141 #ifdef CONFIG_IPV6_PRIVACY
142 	__s32		use_tempaddr;
143 	__s32		temp_valid_lft;
144 	__s32		temp_prefered_lft;
145 	__s32		regen_max_retry;
146 	__s32		max_desync_factor;
147 #endif
148 	__s32		max_addresses;
149 	__s32		accept_ra_defrtr;
150 	__s32		accept_ra_pinfo;
151 #ifdef CONFIG_IPV6_ROUTER_PREF
152 	__s32		accept_ra_rtr_pref;
153 	__s32		rtr_probe_interval;
154 #ifdef CONFIG_IPV6_ROUTE_INFO
155 	__s32		accept_ra_rt_info_max_plen;
156 #endif
157 #endif
158 	__s32		proxy_ndp;
159 	__s32		accept_source_route;
160 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
161 	__s32		optimistic_dad;
162 #endif
163 	void		*sysctl;
164 };
165 
166 /* index values for the variables in ipv6_devconf */
167 enum {
168 	DEVCONF_FORWARDING = 0,
169 	DEVCONF_HOPLIMIT,
170 	DEVCONF_MTU6,
171 	DEVCONF_ACCEPT_RA,
172 	DEVCONF_ACCEPT_REDIRECTS,
173 	DEVCONF_AUTOCONF,
174 	DEVCONF_DAD_TRANSMITS,
175 	DEVCONF_RTR_SOLICITS,
176 	DEVCONF_RTR_SOLICIT_INTERVAL,
177 	DEVCONF_RTR_SOLICIT_DELAY,
178 	DEVCONF_USE_TEMPADDR,
179 	DEVCONF_TEMP_VALID_LFT,
180 	DEVCONF_TEMP_PREFERED_LFT,
181 	DEVCONF_REGEN_MAX_RETRY,
182 	DEVCONF_MAX_DESYNC_FACTOR,
183 	DEVCONF_MAX_ADDRESSES,
184 	DEVCONF_FORCE_MLD_VERSION,
185 	DEVCONF_ACCEPT_RA_DEFRTR,
186 	DEVCONF_ACCEPT_RA_PINFO,
187 	DEVCONF_ACCEPT_RA_RTR_PREF,
188 	DEVCONF_RTR_PROBE_INTERVAL,
189 	DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN,
190 	DEVCONF_PROXY_NDP,
191 	DEVCONF_OPTIMISTIC_DAD,
192 	DEVCONF_ACCEPT_SOURCE_ROUTE,
193 	DEVCONF_MAX
194 };
195 
196 #ifdef __KERNEL__
197 #include <linux/icmpv6.h>
198 #include <linux/tcp.h>
199 #include <linux/udp.h>
200 
201 #include <net/inet_sock.h>
202 
203 static inline struct ipv6hdr *ipv6_hdr(const struct sk_buff *skb)
204 {
205 	return (struct ipv6hdr *)skb_network_header(skb);
206 }
207 
208 static inline struct ipv6hdr *ipipv6_hdr(const struct sk_buff *skb)
209 {
210 	return (struct ipv6hdr *)skb_transport_header(skb);
211 }
212 
213 /*
214    This structure contains results of exthdrs parsing
215    as offsets from skb->nh.
216  */
217 
218 struct inet6_skb_parm {
219 	int			iif;
220 	__u16			ra;
221 	__u16			hop;
222 	__u16			dst0;
223 	__u16			srcrt;
224 	__u16			dst1;
225 	__u16			lastopt;
226 	__u32			nhoff;
227 	__u16			flags;
228 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
229 	__u16			dsthao;
230 #endif
231 
232 #define IP6SKB_XFRM_TRANSFORMED	1
233 };
234 
235 #define IP6CB(skb)	((struct inet6_skb_parm*)((skb)->cb))
236 
237 static inline int inet6_iif(const struct sk_buff *skb)
238 {
239 	return IP6CB(skb)->iif;
240 }
241 
242 struct inet6_request_sock {
243 	struct in6_addr		loc_addr;
244 	struct in6_addr		rmt_addr;
245 	struct sk_buff		*pktopts;
246 	int			iif;
247 };
248 
249 struct tcp6_request_sock {
250 	struct tcp_request_sock	  tcp6rsk_tcp;
251 	struct inet6_request_sock tcp6rsk_inet6;
252 };
253 
254 struct ipv6_mc_socklist;
255 struct ipv6_ac_socklist;
256 struct ipv6_fl_socklist;
257 
258 /**
259  * struct ipv6_pinfo - ipv6 private area
260  *
261  * In the struct sock hierarchy (tcp6_sock, upd6_sock, etc)
262  * this _must_ be the last member, so that inet6_sk_generic
263  * is able to calculate its offset from the base struct sock
264  * by using the struct proto->slab_obj_size member. -acme
265  */
266 struct ipv6_pinfo {
267 	struct in6_addr 	saddr;
268 	struct in6_addr 	rcv_saddr;
269 	struct in6_addr		daddr;
270 	struct in6_addr		*daddr_cache;
271 #ifdef CONFIG_IPV6_SUBTREES
272 	struct in6_addr		*saddr_cache;
273 #endif
274 
275 	__be32			flow_label;
276 	__u32			frag_size;
277 	__s16			hop_limit;
278 	__s16			mcast_hops;
279 	int			mcast_oif;
280 
281 	/* pktoption flags */
282 	union {
283 		struct {
284 			__u16	srcrt:1,
285 				osrcrt:1,
286 			        rxinfo:1,
287 			        rxoinfo:1,
288 				rxhlim:1,
289 				rxohlim:1,
290 				hopopts:1,
291 				ohopopts:1,
292 				dstopts:1,
293 				odstopts:1,
294                                 rxflow:1,
295 				rxtclass:1;
296 		} bits;
297 		__u16		all;
298 	} rxopt;
299 
300 	/* sockopt flags */
301 	__u8			mc_loop:1,
302 	                        recverr:1,
303 	                        sndflow:1,
304 				pmtudisc:2,
305 				ipv6only:1;
306 	__u8			tclass;
307 
308 	__u32			dst_cookie;
309 
310 	struct ipv6_mc_socklist	*ipv6_mc_list;
311 	struct ipv6_ac_socklist	*ipv6_ac_list;
312 	struct ipv6_fl_socklist *ipv6_fl_list;
313 
314 	struct ipv6_txoptions	*opt;
315 	struct sk_buff		*pktoptions;
316 	struct {
317 		struct ipv6_txoptions *opt;
318 		struct rt6_info	*rt;
319 		int hop_limit;
320 		int tclass;
321 	} cork;
322 };
323 
324 /* WARNING: don't change the layout of the members in {raw,udp,tcp}6_sock! */
325 struct raw6_sock {
326 	/* inet_sock has to be the first member of raw6_sock */
327 	struct inet_sock	inet;
328 	__u32			checksum;	/* perform checksum */
329 	__u32			offset;		/* checksum offset  */
330 	struct icmp6_filter	filter;
331 	/* ipv6_pinfo has to be the last member of raw6_sock, see inet6_sk_generic */
332 	struct ipv6_pinfo	inet6;
333 };
334 
335 struct udp6_sock {
336 	struct udp_sock	  udp;
337 	/* ipv6_pinfo has to be the last member of udp6_sock, see inet6_sk_generic */
338 	struct ipv6_pinfo inet6;
339 };
340 
341 struct tcp6_sock {
342 	struct tcp_sock	  tcp;
343 	/* ipv6_pinfo has to be the last member of tcp6_sock, see inet6_sk_generic */
344 	struct ipv6_pinfo inet6;
345 };
346 
347 extern int inet6_sk_rebuild_header(struct sock *sk);
348 
349 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
350 static inline struct ipv6_pinfo * inet6_sk(const struct sock *__sk)
351 {
352 	return inet_sk(__sk)->pinet6;
353 }
354 
355 static inline struct inet6_request_sock *
356 			inet6_rsk(const struct request_sock *rsk)
357 {
358 	return (struct inet6_request_sock *)(((u8 *)rsk) +
359 					     inet_rsk(rsk)->inet6_rsk_offset);
360 }
361 
362 static inline u32 inet6_rsk_offset(struct request_sock *rsk)
363 {
364 	return rsk->rsk_ops->obj_size - sizeof(struct inet6_request_sock);
365 }
366 
367 static inline struct request_sock *inet6_reqsk_alloc(struct request_sock_ops *ops)
368 {
369 	struct request_sock *req = reqsk_alloc(ops);
370 
371 	if (req != NULL)
372 		inet_rsk(req)->inet6_rsk_offset = inet6_rsk_offset(req);
373 
374 	return req;
375 }
376 
377 static inline struct raw6_sock *raw6_sk(const struct sock *sk)
378 {
379 	return (struct raw6_sock *)sk;
380 }
381 
382 static inline void inet_sk_copy_descendant(struct sock *sk_to,
383 					   const struct sock *sk_from)
384 {
385 	int ancestor_size = sizeof(struct inet_sock);
386 
387 	if (sk_from->sk_family == PF_INET6)
388 		ancestor_size += sizeof(struct ipv6_pinfo);
389 
390 	__inet_sk_copy_descendant(sk_to, sk_from, ancestor_size);
391 }
392 
393 #define __ipv6_only_sock(sk)	(inet6_sk(sk)->ipv6only)
394 #define ipv6_only_sock(sk)	((sk)->sk_family == PF_INET6 && __ipv6_only_sock(sk))
395 
396 struct inet6_timewait_sock {
397 	struct in6_addr tw_v6_daddr;
398 	struct in6_addr	tw_v6_rcv_saddr;
399 };
400 
401 struct tcp6_timewait_sock {
402 	struct tcp_timewait_sock   tcp6tw_tcp;
403 	struct inet6_timewait_sock tcp6tw_inet6;
404 };
405 
406 static inline u16 inet6_tw_offset(const struct proto *prot)
407 {
408 	return prot->twsk_prot->twsk_obj_size -
409 			sizeof(struct inet6_timewait_sock);
410 }
411 
412 static inline struct inet6_timewait_sock *inet6_twsk(const struct sock *sk)
413 {
414 	return (struct inet6_timewait_sock *)(((u8 *)sk) +
415 					      inet_twsk(sk)->tw_ipv6_offset);
416 }
417 
418 static inline struct in6_addr *__inet6_rcv_saddr(const struct sock *sk)
419 {
420 	return likely(sk->sk_state != TCP_TIME_WAIT) ?
421 		&inet6_sk(sk)->rcv_saddr : &inet6_twsk(sk)->tw_v6_rcv_saddr;
422 }
423 
424 static inline struct in6_addr *inet6_rcv_saddr(const struct sock *sk)
425 {
426 	return sk->sk_family == AF_INET6 ? __inet6_rcv_saddr(sk) : NULL;
427 }
428 
429 static inline int inet_v6_ipv6only(const struct sock *sk)
430 {
431 	return likely(sk->sk_state != TCP_TIME_WAIT) ?
432 		ipv6_only_sock(sk) : inet_twsk(sk)->tw_ipv6only;
433 }
434 #else
435 #define __ipv6_only_sock(sk)	0
436 #define ipv6_only_sock(sk)	0
437 
438 static inline struct ipv6_pinfo * inet6_sk(const struct sock *__sk)
439 {
440 	return NULL;
441 }
442 
443 static inline struct inet6_request_sock *
444 			inet6_rsk(const struct request_sock *rsk)
445 {
446 	return NULL;
447 }
448 
449 static inline struct raw6_sock *raw6_sk(const struct sock *sk)
450 {
451 	return NULL;
452 }
453 
454 #define __inet6_rcv_saddr(__sk)	NULL
455 #define inet6_rcv_saddr(__sk)	NULL
456 #define tcp_twsk_ipv6only(__sk)		0
457 #define inet_v6_ipv6only(__sk)		0
458 #endif /* defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) */
459 
460 #define INET6_MATCH(__sk, __hash, __saddr, __daddr, __ports, __dif)\
461 	(((__sk)->sk_hash == (__hash))				&& \
462 	 ((*((__portpair *)&(inet_sk(__sk)->dport))) == (__ports))  	&& \
463 	 ((__sk)->sk_family		== AF_INET6)		&& \
464 	 ipv6_addr_equal(&inet6_sk(__sk)->daddr, (__saddr))	&& \
465 	 ipv6_addr_equal(&inet6_sk(__sk)->rcv_saddr, (__daddr))	&& \
466 	 (!((__sk)->sk_bound_dev_if) || ((__sk)->sk_bound_dev_if == (__dif))))
467 
468 #endif /* __KERNEL__ */
469 
470 #endif /* _IPV6_H */
471