xref: /linux-6.15/include/linux/ipv6.h (revision 1671bcfd)
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_min_rtr_lft;
37 	__s32		accept_ra_pinfo;
38 	__s32		ignore_routes_with_linkdown;
39 #ifdef CONFIG_IPV6_ROUTER_PREF
40 	__s32		accept_ra_rtr_pref;
41 	__s32		rtr_probe_interval;
42 #ifdef CONFIG_IPV6_ROUTE_INFO
43 	__s32		accept_ra_rt_info_min_plen;
44 	__s32		accept_ra_rt_info_max_plen;
45 #endif
46 #endif
47 	__s32		proxy_ndp;
48 	__s32		accept_source_route;
49 	__s32		accept_ra_from_local;
50 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
51 	__s32		optimistic_dad;
52 	__s32		use_optimistic;
53 #endif
54 #ifdef CONFIG_IPV6_MROUTE
55 	atomic_t	mc_forwarding;
56 #endif
57 	__s32		disable_ipv6;
58 	__s32		drop_unicast_in_l2_multicast;
59 	__s32		accept_dad;
60 	__s32		force_tllao;
61 	__s32           ndisc_notify;
62 	__s32		suppress_frag_ndisc;
63 	__s32		accept_ra_mtu;
64 	__s32		drop_unsolicited_na;
65 	__s32		accept_untracked_na;
66 	struct ipv6_stable_secret {
67 		bool initialized;
68 		struct in6_addr secret;
69 	} stable_secret;
70 	__s32		use_oif_addrs_only;
71 	__s32		keep_addr_on_down;
72 	__s32		seg6_enabled;
73 #ifdef CONFIG_IPV6_SEG6_HMAC
74 	__s32		seg6_require_hmac;
75 #endif
76 	__u32		enhanced_dad;
77 	__u32		addr_gen_mode;
78 	__s32		disable_policy;
79 	__s32           ndisc_tclass;
80 	__s32		rpl_seg_enabled;
81 	__u32		ioam6_id;
82 	__u32		ioam6_id_wide;
83 	__u8		ioam6_enabled;
84 	__u8		ndisc_evict_nocarrier;
85 
86 	struct ctl_table_header *sysctl_header;
87 };
88 
89 struct ipv6_params {
90 	__s32 disable_ipv6;
91 	__s32 autoconf;
92 };
93 extern struct ipv6_params ipv6_defaults;
94 #include <linux/tcp.h>
95 #include <linux/udp.h>
96 
97 #include <net/inet_sock.h>
98 
99 static inline struct ipv6hdr *ipv6_hdr(const struct sk_buff *skb)
100 {
101 	return (struct ipv6hdr *)skb_network_header(skb);
102 }
103 
104 static inline struct ipv6hdr *inner_ipv6_hdr(const struct sk_buff *skb)
105 {
106 	return (struct ipv6hdr *)skb_inner_network_header(skb);
107 }
108 
109 static inline struct ipv6hdr *ipipv6_hdr(const struct sk_buff *skb)
110 {
111 	return (struct ipv6hdr *)skb_transport_header(skb);
112 }
113 
114 static inline unsigned int ipv6_transport_len(const struct sk_buff *skb)
115 {
116 	return ntohs(ipv6_hdr(skb)->payload_len) + sizeof(struct ipv6hdr) -
117 	       skb_network_header_len(skb);
118 }
119 
120 /*
121    This structure contains results of exthdrs parsing
122    as offsets from skb->nh.
123  */
124 
125 struct inet6_skb_parm {
126 	int			iif;
127 	__be16			ra;
128 	__u16			dst0;
129 	__u16			srcrt;
130 	__u16			dst1;
131 	__u16			lastopt;
132 	__u16			nhoff;
133 	__u16			flags;
134 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
135 	__u16			dsthao;
136 #endif
137 	__u16			frag_max_size;
138 	__u16			srhoff;
139 
140 #define IP6SKB_XFRM_TRANSFORMED	1
141 #define IP6SKB_FORWARDED	2
142 #define IP6SKB_REROUTED		4
143 #define IP6SKB_ROUTERALERT	8
144 #define IP6SKB_FRAGMENTED      16
145 #define IP6SKB_HOPBYHOP        32
146 #define IP6SKB_L3SLAVE         64
147 #define IP6SKB_JUMBOGRAM      128
148 #define IP6SKB_SEG6	      256
149 #define IP6SKB_FAKEJUMBO      512
150 };
151 
152 #if defined(CONFIG_NET_L3_MASTER_DEV)
153 static inline bool ipv6_l3mdev_skb(__u16 flags)
154 {
155 	return flags & IP6SKB_L3SLAVE;
156 }
157 #else
158 static inline bool ipv6_l3mdev_skb(__u16 flags)
159 {
160 	return false;
161 }
162 #endif
163 
164 #define IP6CB(skb)	((struct inet6_skb_parm*)((skb)->cb))
165 #define IP6CBMTU(skb)	((struct ip6_mtuinfo *)((skb)->cb))
166 
167 static inline int inet6_iif(const struct sk_buff *skb)
168 {
169 	bool l3_slave = ipv6_l3mdev_skb(IP6CB(skb)->flags);
170 
171 	return l3_slave ? skb->skb_iif : IP6CB(skb)->iif;
172 }
173 
174 static inline bool inet6_is_jumbogram(const struct sk_buff *skb)
175 {
176 	return !!(IP6CB(skb)->flags & IP6SKB_JUMBOGRAM);
177 }
178 
179 /* can not be used in TCP layer after tcp_v6_fill_cb */
180 static inline int inet6_sdif(const struct sk_buff *skb)
181 {
182 #if IS_ENABLED(CONFIG_NET_L3_MASTER_DEV)
183 	if (skb && ipv6_l3mdev_skb(IP6CB(skb)->flags))
184 		return IP6CB(skb)->iif;
185 #endif
186 	return 0;
187 }
188 
189 struct tcp6_request_sock {
190 	struct tcp_request_sock	  tcp6rsk_tcp;
191 };
192 
193 struct ipv6_mc_socklist;
194 struct ipv6_ac_socklist;
195 struct ipv6_fl_socklist;
196 
197 struct inet6_cork {
198 	struct ipv6_txoptions *opt;
199 	u8 hop_limit;
200 	u8 tclass;
201 };
202 
203 /**
204  * struct ipv6_pinfo - ipv6 private area
205  *
206  * In the struct sock hierarchy (tcp6_sock, upd6_sock, etc)
207  * this _must_ be the last member, so that inet6_sk_generic
208  * is able to calculate its offset from the base struct sock
209  * by using the struct proto->slab_obj_size member. -acme
210  */
211 struct ipv6_pinfo {
212 	struct in6_addr 	saddr;
213 	struct in6_pktinfo	sticky_pktinfo;
214 	const struct in6_addr		*daddr_cache;
215 #ifdef CONFIG_IPV6_SUBTREES
216 	const struct in6_addr		*saddr_cache;
217 #endif
218 
219 	__be32			flow_label;
220 	__u32			frag_size;
221 
222 	/*
223 	 * Packed in 16bits.
224 	 * Omit one shift by putting the signed field at MSB.
225 	 */
226 #if defined(__BIG_ENDIAN_BITFIELD)
227 	__s16			hop_limit:9;
228 	__u16			__unused_1:7;
229 #else
230 	__u16			__unused_1:7;
231 	__s16			hop_limit:9;
232 #endif
233 
234 #if defined(__BIG_ENDIAN_BITFIELD)
235 	/* Packed in 16bits. */
236 	__s16			mcast_hops:9;
237 	__u16			__unused_2:6,
238 				mc_loop:1;
239 #else
240 	__u16			mc_loop:1,
241 				__unused_2:6;
242 	__s16			mcast_hops:9;
243 #endif
244 	int			ucast_oif;
245 	int			mcast_oif;
246 
247 	/* pktoption flags */
248 	union {
249 		struct {
250 			__u16	srcrt:1,
251 				osrcrt:1,
252 			        rxinfo:1,
253 			        rxoinfo:1,
254 				rxhlim:1,
255 				rxohlim:1,
256 				hopopts:1,
257 				ohopopts:1,
258 				dstopts:1,
259 				odstopts:1,
260                                 rxflow:1,
261 				rxtclass:1,
262 				rxpmtu:1,
263 				rxorigdstaddr:1,
264 				recvfragsize:1;
265 				/* 1 bits hole */
266 		} bits;
267 		__u16		all;
268 	} rxopt;
269 
270 	/* sockopt flags */
271 	__u16			recverr:1,
272 	                        sndflow:1,
273 				repflow:1,
274 				pmtudisc:3,
275 				padding:1,	/* 1 bit hole */
276 				srcprefs:3,	/* 001: prefer temporary address
277 						 * 010: prefer public address
278 						 * 100: prefer care-of address
279 						 */
280 				dontfrag:1,
281 				autoflowlabel:1,
282 				autoflowlabel_set:1,
283 				mc_all:1,
284 				recverr_rfc4884:1,
285 				rtalert_isolate:1;
286 	__u8			min_hopcount;
287 	__u8			tclass;
288 	__be32			rcv_flowinfo;
289 
290 	__u32			dst_cookie;
291 
292 	struct ipv6_mc_socklist	__rcu *ipv6_mc_list;
293 	struct ipv6_ac_socklist	*ipv6_ac_list;
294 	struct ipv6_fl_socklist __rcu *ipv6_fl_list;
295 
296 	struct ipv6_txoptions __rcu	*opt;
297 	struct sk_buff		*pktoptions;
298 	struct sk_buff		*rxpmtu;
299 	struct inet6_cork	cork;
300 };
301 
302 /* WARNING: don't change the layout of the members in {raw,udp,tcp}6_sock! */
303 struct raw6_sock {
304 	/* inet_sock has to be the first member of raw6_sock */
305 	struct inet_sock	inet;
306 	__u32			checksum;	/* perform checksum */
307 	__u32			offset;		/* checksum offset  */
308 	struct icmp6_filter	filter;
309 	__u32			ip6mr_table;
310 	/* ipv6_pinfo has to be the last member of raw6_sock, see inet6_sk_generic */
311 	struct ipv6_pinfo	inet6;
312 };
313 
314 struct udp6_sock {
315 	struct udp_sock	  udp;
316 	/* ipv6_pinfo has to be the last member of udp6_sock, see inet6_sk_generic */
317 	struct ipv6_pinfo inet6;
318 };
319 
320 struct tcp6_sock {
321 	struct tcp_sock	  tcp;
322 	/* ipv6_pinfo has to be the last member of tcp6_sock, see inet6_sk_generic */
323 	struct ipv6_pinfo inet6;
324 };
325 
326 extern int inet6_sk_rebuild_header(struct sock *sk);
327 
328 struct tcp6_timewait_sock {
329 	struct tcp_timewait_sock   tcp6tw_tcp;
330 };
331 
332 #if IS_ENABLED(CONFIG_IPV6)
333 bool ipv6_mod_enabled(void);
334 
335 static inline struct ipv6_pinfo *inet6_sk(const struct sock *__sk)
336 {
337 	return sk_fullsock(__sk) ? inet_sk(__sk)->pinet6 : NULL;
338 }
339 
340 #define raw6_sk(ptr) container_of_const(ptr, struct raw6_sock, inet.sk)
341 
342 #define ipv6_only_sock(sk)	(sk->sk_ipv6only)
343 #define ipv6_sk_rxinfo(sk)	((sk)->sk_family == PF_INET6 && \
344 				 inet6_sk(sk)->rxopt.bits.rxinfo)
345 
346 static inline const struct in6_addr *inet6_rcv_saddr(const struct sock *sk)
347 {
348 	if (sk->sk_family == AF_INET6)
349 		return &sk->sk_v6_rcv_saddr;
350 	return NULL;
351 }
352 
353 static inline int inet_v6_ipv6only(const struct sock *sk)
354 {
355 	/* ipv6only field is at same position for timewait and other sockets */
356 	return ipv6_only_sock(sk);
357 }
358 #else
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 raw6_sock *raw6_sk(const struct sock *sk)
373 {
374 	return NULL;
375 }
376 
377 #define inet6_rcv_saddr(__sk)	NULL
378 #define inet_v6_ipv6only(__sk)		0
379 #endif /* IS_ENABLED(CONFIG_IPV6) */
380 #endif /* _IPV6_H */
381