xref: /linux-6.15/include/linux/ipv6.h (revision cd455ebb)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _IPV6_H
3 #define _IPV6_H
4 
5 #include <uapi/linux/ipv6.h>
6 
7 #define ipv6_optlen(p)  (((p)->hdrlen+1) << 3)
8 #define ipv6_authlen(p) (((p)->hdrlen+2) << 2)
9 /*
10  * This structure contains configuration options per IPv6 link.
11  */
12 struct ipv6_devconf {
13 	__s32		forwarding;
14 	__s32		hop_limit;
15 	__s32		mtu6;
16 	__s32		accept_ra;
17 	__s32		accept_redirects;
18 	__s32		autoconf;
19 	__s32		dad_transmits;
20 	__s32		rtr_solicits;
21 	__s32		rtr_solicit_interval;
22 	__s32		rtr_solicit_max_interval;
23 	__s32		rtr_solicit_delay;
24 	__s32		force_mld_version;
25 	__s32		mldv1_unsolicited_report_interval;
26 	__s32		mldv2_unsolicited_report_interval;
27 	__s32		use_tempaddr;
28 	__s32		temp_valid_lft;
29 	__s32		temp_prefered_lft;
30 	__s32		regen_max_retry;
31 	__s32		max_desync_factor;
32 	__s32		max_addresses;
33 	__s32		accept_ra_defrtr;
34 	__u32		ra_defrtr_metric;
35 	__s32		accept_ra_min_hop_limit;
36 	__s32		accept_ra_pinfo;
37 	__s32		ignore_routes_with_linkdown;
38 #ifdef CONFIG_IPV6_ROUTER_PREF
39 	__s32		accept_ra_rtr_pref;
40 	__s32		rtr_probe_interval;
41 #ifdef CONFIG_IPV6_ROUTE_INFO
42 	__s32		accept_ra_rt_info_min_plen;
43 	__s32		accept_ra_rt_info_max_plen;
44 #endif
45 #endif
46 	__s32		proxy_ndp;
47 	__s32		accept_source_route;
48 	__s32		accept_ra_from_local;
49 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
50 	__s32		optimistic_dad;
51 	__s32		use_optimistic;
52 #endif
53 #ifdef CONFIG_IPV6_MROUTE
54 	__s32		mc_forwarding;
55 #endif
56 	__s32		disable_ipv6;
57 	__s32		drop_unicast_in_l2_multicast;
58 	__s32		accept_dad;
59 	__s32		force_tllao;
60 	__s32           ndisc_notify;
61 	__s32		suppress_frag_ndisc;
62 	__s32		accept_ra_mtu;
63 	__s32		drop_unsolicited_na;
64 	struct ipv6_stable_secret {
65 		bool initialized;
66 		struct in6_addr secret;
67 	} stable_secret;
68 	__s32		use_oif_addrs_only;
69 	__s32		keep_addr_on_down;
70 	__s32		seg6_enabled;
71 #ifdef CONFIG_IPV6_SEG6_HMAC
72 	__s32		seg6_require_hmac;
73 #endif
74 	__u32		enhanced_dad;
75 	__u32		addr_gen_mode;
76 	__s32		disable_policy;
77 	__s32           ndisc_tclass;
78 	__s32		rpl_seg_enabled;
79 	__u32		ioam6_id;
80 	__u32		ioam6_id_wide;
81 	__u8		ioam6_enabled;
82 	__u8		ndisc_evict_nocarrier;
83 
84 	struct ctl_table_header *sysctl_header;
85 };
86 
87 struct ipv6_params {
88 	__s32 disable_ipv6;
89 	__s32 autoconf;
90 };
91 extern struct ipv6_params ipv6_defaults;
92 #include <linux/tcp.h>
93 #include <linux/udp.h>
94 
95 #include <net/inet_sock.h>
96 
97 static inline struct ipv6hdr *ipv6_hdr(const struct sk_buff *skb)
98 {
99 	return (struct ipv6hdr *)skb_network_header(skb);
100 }
101 
102 static inline struct ipv6hdr *inner_ipv6_hdr(const struct sk_buff *skb)
103 {
104 	return (struct ipv6hdr *)skb_inner_network_header(skb);
105 }
106 
107 static inline struct ipv6hdr *ipipv6_hdr(const struct sk_buff *skb)
108 {
109 	return (struct ipv6hdr *)skb_transport_header(skb);
110 }
111 
112 static inline unsigned int ipv6_transport_len(const struct sk_buff *skb)
113 {
114 	return ntohs(ipv6_hdr(skb)->payload_len) + sizeof(struct ipv6hdr) -
115 	       skb_network_header_len(skb);
116 }
117 
118 /*
119    This structure contains results of exthdrs parsing
120    as offsets from skb->nh.
121  */
122 
123 struct inet6_skb_parm {
124 	int			iif;
125 	__be16			ra;
126 	__u16			dst0;
127 	__u16			srcrt;
128 	__u16			dst1;
129 	__u16			lastopt;
130 	__u16			nhoff;
131 	__u16			flags;
132 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
133 	__u16			dsthao;
134 #endif
135 	__u16			frag_max_size;
136 
137 #define IP6SKB_XFRM_TRANSFORMED	1
138 #define IP6SKB_FORWARDED	2
139 #define IP6SKB_REROUTED		4
140 #define IP6SKB_ROUTERALERT	8
141 #define IP6SKB_FRAGMENTED      16
142 #define IP6SKB_HOPBYHOP        32
143 #define IP6SKB_L3SLAVE         64
144 #define IP6SKB_JUMBOGRAM      128
145 };
146 
147 #if defined(CONFIG_NET_L3_MASTER_DEV)
148 static inline bool ipv6_l3mdev_skb(__u16 flags)
149 {
150 	return flags & IP6SKB_L3SLAVE;
151 }
152 #else
153 static inline bool ipv6_l3mdev_skb(__u16 flags)
154 {
155 	return false;
156 }
157 #endif
158 
159 #define IP6CB(skb)	((struct inet6_skb_parm*)((skb)->cb))
160 #define IP6CBMTU(skb)	((struct ip6_mtuinfo *)((skb)->cb))
161 
162 static inline int inet6_iif(const struct sk_buff *skb)
163 {
164 	bool l3_slave = ipv6_l3mdev_skb(IP6CB(skb)->flags);
165 
166 	return l3_slave ? skb->skb_iif : IP6CB(skb)->iif;
167 }
168 
169 static inline bool inet6_is_jumbogram(const struct sk_buff *skb)
170 {
171 	return !!(IP6CB(skb)->flags & IP6SKB_JUMBOGRAM);
172 }
173 
174 /* can not be used in TCP layer after tcp_v6_fill_cb */
175 static inline int inet6_sdif(const struct sk_buff *skb)
176 {
177 #if IS_ENABLED(CONFIG_NET_L3_MASTER_DEV)
178 	if (skb && ipv6_l3mdev_skb(IP6CB(skb)->flags))
179 		return IP6CB(skb)->iif;
180 #endif
181 	return 0;
182 }
183 
184 struct tcp6_request_sock {
185 	struct tcp_request_sock	  tcp6rsk_tcp;
186 };
187 
188 struct ipv6_mc_socklist;
189 struct ipv6_ac_socklist;
190 struct ipv6_fl_socklist;
191 
192 struct inet6_cork {
193 	struct ipv6_txoptions *opt;
194 	u8 hop_limit;
195 	u8 tclass;
196 };
197 
198 /**
199  * struct ipv6_pinfo - ipv6 private area
200  *
201  * In the struct sock hierarchy (tcp6_sock, upd6_sock, etc)
202  * this _must_ be the last member, so that inet6_sk_generic
203  * is able to calculate its offset from the base struct sock
204  * by using the struct proto->slab_obj_size member. -acme
205  */
206 struct ipv6_pinfo {
207 	struct in6_addr 	saddr;
208 	struct in6_pktinfo	sticky_pktinfo;
209 	const struct in6_addr		*daddr_cache;
210 #ifdef CONFIG_IPV6_SUBTREES
211 	const struct in6_addr		*saddr_cache;
212 #endif
213 
214 	__be32			flow_label;
215 	__u32			frag_size;
216 
217 	/*
218 	 * Packed in 16bits.
219 	 * Omit one shift by putting the signed field at MSB.
220 	 */
221 #if defined(__BIG_ENDIAN_BITFIELD)
222 	__s16			hop_limit:9;
223 	__u16			__unused_1:7;
224 #else
225 	__u16			__unused_1:7;
226 	__s16			hop_limit:9;
227 #endif
228 
229 #if defined(__BIG_ENDIAN_BITFIELD)
230 	/* Packed in 16bits. */
231 	__s16			mcast_hops:9;
232 	__u16			__unused_2:6,
233 				mc_loop:1;
234 #else
235 	__u16			mc_loop:1,
236 				__unused_2:6;
237 	__s16			mcast_hops:9;
238 #endif
239 	int			ucast_oif;
240 	int			mcast_oif;
241 
242 	/* pktoption flags */
243 	union {
244 		struct {
245 			__u16	srcrt:1,
246 				osrcrt:1,
247 			        rxinfo:1,
248 			        rxoinfo:1,
249 				rxhlim:1,
250 				rxohlim:1,
251 				hopopts:1,
252 				ohopopts:1,
253 				dstopts:1,
254 				odstopts:1,
255                                 rxflow:1,
256 				rxtclass:1,
257 				rxpmtu:1,
258 				rxorigdstaddr:1,
259 				recvfragsize:1;
260 				/* 1 bits hole */
261 		} bits;
262 		__u16		all;
263 	} rxopt;
264 
265 	/* sockopt flags */
266 	__u16			recverr:1,
267 	                        sndflow:1,
268 				repflow:1,
269 				pmtudisc:3,
270 				padding:1,	/* 1 bit hole */
271 				srcprefs:3,	/* 001: prefer temporary address
272 						 * 010: prefer public address
273 						 * 100: prefer care-of address
274 						 */
275 				dontfrag:1,
276 				autoflowlabel:1,
277 				autoflowlabel_set:1,
278 				mc_all:1,
279 				recverr_rfc4884:1,
280 				rtalert_isolate:1;
281 	__u8			min_hopcount;
282 	__u8			tclass;
283 	__be32			rcv_flowinfo;
284 
285 	__u32			dst_cookie;
286 
287 	struct ipv6_mc_socklist	__rcu *ipv6_mc_list;
288 	struct ipv6_ac_socklist	*ipv6_ac_list;
289 	struct ipv6_fl_socklist __rcu *ipv6_fl_list;
290 
291 	struct ipv6_txoptions __rcu	*opt;
292 	struct sk_buff		*pktoptions;
293 	struct sk_buff		*rxpmtu;
294 	struct inet6_cork	cork;
295 };
296 
297 /* WARNING: don't change the layout of the members in {raw,udp,tcp}6_sock! */
298 struct raw6_sock {
299 	/* inet_sock has to be the first member of raw6_sock */
300 	struct inet_sock	inet;
301 	__u32			checksum;	/* perform checksum */
302 	__u32			offset;		/* checksum offset  */
303 	struct icmp6_filter	filter;
304 	__u32			ip6mr_table;
305 	/* ipv6_pinfo has to be the last member of raw6_sock, see inet6_sk_generic */
306 	struct ipv6_pinfo	inet6;
307 };
308 
309 struct udp6_sock {
310 	struct udp_sock	  udp;
311 	/* ipv6_pinfo has to be the last member of udp6_sock, see inet6_sk_generic */
312 	struct ipv6_pinfo inet6;
313 };
314 
315 struct tcp6_sock {
316 	struct tcp_sock	  tcp;
317 	/* ipv6_pinfo has to be the last member of tcp6_sock, see inet6_sk_generic */
318 	struct ipv6_pinfo inet6;
319 };
320 
321 extern int inet6_sk_rebuild_header(struct sock *sk);
322 
323 struct tcp6_timewait_sock {
324 	struct tcp_timewait_sock   tcp6tw_tcp;
325 };
326 
327 #if IS_ENABLED(CONFIG_IPV6)
328 bool ipv6_mod_enabled(void);
329 
330 static inline struct ipv6_pinfo *inet6_sk(const struct sock *__sk)
331 {
332 	return sk_fullsock(__sk) ? inet_sk(__sk)->pinet6 : NULL;
333 }
334 
335 static inline struct raw6_sock *raw6_sk(const struct sock *sk)
336 {
337 	return (struct raw6_sock *)sk;
338 }
339 
340 #define __ipv6_only_sock(sk)	(sk->sk_ipv6only)
341 #define ipv6_only_sock(sk)	(__ipv6_only_sock(sk))
342 #define ipv6_sk_rxinfo(sk)	((sk)->sk_family == PF_INET6 && \
343 				 inet6_sk(sk)->rxopt.bits.rxinfo)
344 
345 static inline const struct in6_addr *inet6_rcv_saddr(const struct sock *sk)
346 {
347 	if (sk->sk_family == AF_INET6)
348 		return &sk->sk_v6_rcv_saddr;
349 	return NULL;
350 }
351 
352 static inline int inet_v6_ipv6only(const struct sock *sk)
353 {
354 	/* ipv6only field is at same position for timewait and other sockets */
355 	return ipv6_only_sock(sk);
356 }
357 #else
358 #define __ipv6_only_sock(sk)	0
359 #define ipv6_only_sock(sk)	0
360 #define ipv6_sk_rxinfo(sk)	0
361 
362 static inline bool ipv6_mod_enabled(void)
363 {
364 	return false;
365 }
366 
367 static inline struct ipv6_pinfo * inet6_sk(const struct sock *__sk)
368 {
369 	return NULL;
370 }
371 
372 static inline struct inet6_request_sock *
373 			inet6_rsk(const struct request_sock *rsk)
374 {
375 	return NULL;
376 }
377 
378 static inline struct raw6_sock *raw6_sk(const struct sock *sk)
379 {
380 	return NULL;
381 }
382 
383 #define inet6_rcv_saddr(__sk)	NULL
384 #define tcp_twsk_ipv6only(__sk)		0
385 #define inet_v6_ipv6only(__sk)		0
386 #endif /* IS_ENABLED(CONFIG_IPV6) */
387 #endif /* _IPV6_H */
388