xref: /linux-6.15/include/linux/ipv6.h (revision bbb03029)
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_min_plen;
41 	__s32		accept_ra_rt_info_max_plen;
42 #endif
43 #endif
44 	__s32		proxy_ndp;
45 	__s32		accept_source_route;
46 	__s32		accept_ra_from_local;
47 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
48 	__s32		optimistic_dad;
49 	__s32		use_optimistic;
50 #endif
51 #ifdef CONFIG_IPV6_MROUTE
52 	__s32		mc_forwarding;
53 #endif
54 	__s32		disable_ipv6;
55 	__s32		drop_unicast_in_l2_multicast;
56 	__s32		accept_dad;
57 	__s32		force_tllao;
58 	__s32           ndisc_notify;
59 	__s32		suppress_frag_ndisc;
60 	__s32		accept_ra_mtu;
61 	__s32		drop_unsolicited_na;
62 	struct ipv6_stable_secret {
63 		bool initialized;
64 		struct in6_addr secret;
65 	} stable_secret;
66 	__s32		use_oif_addrs_only;
67 	__s32		keep_addr_on_down;
68 	__s32		seg6_enabled;
69 #ifdef CONFIG_IPV6_SEG6_HMAC
70 	__s32		seg6_require_hmac;
71 #endif
72 	__u32		enhanced_dad;
73 	__u32		addr_gen_mode;
74 	__s32		disable_policy;
75 
76 	struct ctl_table_header *sysctl_header;
77 };
78 
79 struct ipv6_params {
80 	__s32 disable_ipv6;
81 	__s32 autoconf;
82 };
83 extern struct ipv6_params ipv6_defaults;
84 #include <linux/icmpv6.h>
85 #include <linux/tcp.h>
86 #include <linux/udp.h>
87 
88 #include <net/inet_sock.h>
89 
90 static inline struct ipv6hdr *ipv6_hdr(const struct sk_buff *skb)
91 {
92 	return (struct ipv6hdr *)skb_network_header(skb);
93 }
94 
95 static inline struct ipv6hdr *inner_ipv6_hdr(const struct sk_buff *skb)
96 {
97 	return (struct ipv6hdr *)skb_inner_network_header(skb);
98 }
99 
100 static inline struct ipv6hdr *ipipv6_hdr(const struct sk_buff *skb)
101 {
102 	return (struct ipv6hdr *)skb_transport_header(skb);
103 }
104 
105 /*
106    This structure contains results of exthdrs parsing
107    as offsets from skb->nh.
108  */
109 
110 struct inet6_skb_parm {
111 	int			iif;
112 	__be16			ra;
113 	__u16			dst0;
114 	__u16			srcrt;
115 	__u16			dst1;
116 	__u16			lastopt;
117 	__u16			nhoff;
118 	__u16			flags;
119 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
120 	__u16			dsthao;
121 #endif
122 	__u16			frag_max_size;
123 
124 #define IP6SKB_XFRM_TRANSFORMED	1
125 #define IP6SKB_FORWARDED	2
126 #define IP6SKB_REROUTED		4
127 #define IP6SKB_ROUTERALERT	8
128 #define IP6SKB_FRAGMENTED      16
129 #define IP6SKB_HOPBYHOP        32
130 #define IP6SKB_L3SLAVE         64
131 #define IP6SKB_JUMBOGRAM      128
132 };
133 
134 #if defined(CONFIG_NET_L3_MASTER_DEV)
135 static inline bool ipv6_l3mdev_skb(__u16 flags)
136 {
137 	return flags & IP6SKB_L3SLAVE;
138 }
139 #else
140 static inline bool ipv6_l3mdev_skb(__u16 flags)
141 {
142 	return false;
143 }
144 #endif
145 
146 #define IP6CB(skb)	((struct inet6_skb_parm*)((skb)->cb))
147 #define IP6CBMTU(skb)	((struct ip6_mtuinfo *)((skb)->cb))
148 
149 static inline int inet6_iif(const struct sk_buff *skb)
150 {
151 	bool l3_slave = ipv6_l3mdev_skb(IP6CB(skb)->flags);
152 
153 	return l3_slave ? skb->skb_iif : IP6CB(skb)->iif;
154 }
155 
156 static inline bool inet6_is_jumbogram(const struct sk_buff *skb)
157 {
158 	return !!(IP6CB(skb)->flags & IP6SKB_JUMBOGRAM);
159 }
160 
161 /* can not be used in TCP layer after tcp_v6_fill_cb */
162 static inline bool inet6_exact_dif_match(struct net *net, struct sk_buff *skb)
163 {
164 #if defined(CONFIG_NET_L3_MASTER_DEV)
165 	if (!net->ipv4.sysctl_tcp_l3mdev_accept &&
166 	    skb && ipv6_l3mdev_skb(IP6CB(skb)->flags))
167 		return true;
168 #endif
169 	return false;
170 }
171 
172 struct tcp6_request_sock {
173 	struct tcp_request_sock	  tcp6rsk_tcp;
174 };
175 
176 struct ipv6_mc_socklist;
177 struct ipv6_ac_socklist;
178 struct ipv6_fl_socklist;
179 
180 struct inet6_cork {
181 	struct ipv6_txoptions *opt;
182 	u8 hop_limit;
183 	u8 tclass;
184 };
185 
186 /**
187  * struct ipv6_pinfo - ipv6 private area
188  *
189  * In the struct sock hierarchy (tcp6_sock, upd6_sock, etc)
190  * this _must_ be the last member, so that inet6_sk_generic
191  * is able to calculate its offset from the base struct sock
192  * by using the struct proto->slab_obj_size member. -acme
193  */
194 struct ipv6_pinfo {
195 	struct in6_addr 	saddr;
196 	struct in6_pktinfo	sticky_pktinfo;
197 	const struct in6_addr		*daddr_cache;
198 #ifdef CONFIG_IPV6_SUBTREES
199 	const struct in6_addr		*saddr_cache;
200 #endif
201 
202 	__be32			flow_label;
203 	__u32			frag_size;
204 
205 	/*
206 	 * Packed in 16bits.
207 	 * Omit one shift by by putting the signed field at MSB.
208 	 */
209 #if defined(__BIG_ENDIAN_BITFIELD)
210 	__s16			hop_limit:9;
211 	__u16			__unused_1:7;
212 #else
213 	__u16			__unused_1:7;
214 	__s16			hop_limit:9;
215 #endif
216 
217 #if defined(__BIG_ENDIAN_BITFIELD)
218 	/* Packed in 16bits. */
219 	__s16			mcast_hops:9;
220 	__u16			__unused_2:6,
221 				mc_loop:1;
222 #else
223 	__u16			mc_loop:1,
224 				__unused_2:6;
225 	__s16			mcast_hops:9;
226 #endif
227 	int			ucast_oif;
228 	int			mcast_oif;
229 
230 	/* pktoption flags */
231 	union {
232 		struct {
233 			__u16	srcrt:1,
234 				osrcrt:1,
235 			        rxinfo:1,
236 			        rxoinfo:1,
237 				rxhlim:1,
238 				rxohlim:1,
239 				hopopts:1,
240 				ohopopts:1,
241 				dstopts:1,
242 				odstopts:1,
243                                 rxflow:1,
244 				rxtclass:1,
245 				rxpmtu:1,
246 				rxorigdstaddr:1,
247 				recvfragsize:1;
248 				/* 1 bits hole */
249 		} bits;
250 		__u16		all;
251 	} rxopt;
252 
253 	/* sockopt flags */
254 	__u16			recverr:1,
255 	                        sndflow:1,
256 				repflow:1,
257 				pmtudisc:3,
258 				padding:1,	/* 1 bit hole */
259 				srcprefs:3,	/* 001: prefer temporary address
260 						 * 010: prefer public address
261 						 * 100: prefer care-of address
262 						 */
263 				dontfrag:1,
264 				autoflowlabel:1;
265 	__u8			min_hopcount;
266 	__u8			tclass;
267 	__be32			rcv_flowinfo;
268 
269 	__u32			dst_cookie;
270 	__u32			rx_dst_cookie;
271 
272 	struct ipv6_mc_socklist	__rcu *ipv6_mc_list;
273 	struct ipv6_ac_socklist	*ipv6_ac_list;
274 	struct ipv6_fl_socklist __rcu *ipv6_fl_list;
275 
276 	struct ipv6_txoptions __rcu	*opt;
277 	struct sk_buff		*pktoptions;
278 	struct sk_buff		*rxpmtu;
279 	struct inet6_cork	cork;
280 };
281 
282 /* WARNING: don't change the layout of the members in {raw,udp,tcp}6_sock! */
283 struct raw6_sock {
284 	/* inet_sock has to be the first member of raw6_sock */
285 	struct inet_sock	inet;
286 	__u32			checksum;	/* perform checksum */
287 	__u32			offset;		/* checksum offset  */
288 	struct icmp6_filter	filter;
289 	__u32			ip6mr_table;
290 	/* ipv6_pinfo has to be the last member of raw6_sock, see inet6_sk_generic */
291 	struct ipv6_pinfo	inet6;
292 };
293 
294 struct udp6_sock {
295 	struct udp_sock	  udp;
296 	/* ipv6_pinfo has to be the last member of udp6_sock, see inet6_sk_generic */
297 	struct ipv6_pinfo inet6;
298 };
299 
300 struct tcp6_sock {
301 	struct tcp_sock	  tcp;
302 	/* ipv6_pinfo has to be the last member of tcp6_sock, see inet6_sk_generic */
303 	struct ipv6_pinfo inet6;
304 };
305 
306 extern int inet6_sk_rebuild_header(struct sock *sk);
307 
308 struct tcp6_timewait_sock {
309 	struct tcp_timewait_sock   tcp6tw_tcp;
310 };
311 
312 #if IS_ENABLED(CONFIG_IPV6)
313 bool ipv6_mod_enabled(void);
314 
315 static inline struct ipv6_pinfo *inet6_sk(const struct sock *__sk)
316 {
317 	return sk_fullsock(__sk) ? inet_sk(__sk)->pinet6 : NULL;
318 }
319 
320 static inline struct raw6_sock *raw6_sk(const struct sock *sk)
321 {
322 	return (struct raw6_sock *)sk;
323 }
324 
325 static inline void inet_sk_copy_descendant(struct sock *sk_to,
326 					   const struct sock *sk_from)
327 {
328 	int ancestor_size = sizeof(struct inet_sock);
329 
330 	if (sk_from->sk_family == PF_INET6)
331 		ancestor_size += sizeof(struct ipv6_pinfo);
332 
333 	__inet_sk_copy_descendant(sk_to, sk_from, ancestor_size);
334 }
335 
336 #define __ipv6_only_sock(sk)	(sk->sk_ipv6only)
337 #define ipv6_only_sock(sk)	(__ipv6_only_sock(sk))
338 #define ipv6_sk_rxinfo(sk)	((sk)->sk_family == PF_INET6 && \
339 				 inet6_sk(sk)->rxopt.bits.rxinfo)
340 
341 static inline const struct in6_addr *inet6_rcv_saddr(const struct sock *sk)
342 {
343 	if (sk->sk_family == AF_INET6)
344 		return &sk->sk_v6_rcv_saddr;
345 	return NULL;
346 }
347 
348 static inline int inet_v6_ipv6only(const struct sock *sk)
349 {
350 	/* ipv6only field is at same position for timewait and other sockets */
351 	return ipv6_only_sock(sk);
352 }
353 #else
354 #define __ipv6_only_sock(sk)	0
355 #define ipv6_only_sock(sk)	0
356 #define ipv6_sk_rxinfo(sk)	0
357 
358 static inline bool ipv6_mod_enabled(void)
359 {
360 	return false;
361 }
362 
363 static inline struct ipv6_pinfo * inet6_sk(const struct sock *__sk)
364 {
365 	return NULL;
366 }
367 
368 static inline struct inet6_request_sock *
369 			inet6_rsk(const struct request_sock *rsk)
370 {
371 	return NULL;
372 }
373 
374 static inline struct raw6_sock *raw6_sk(const struct sock *sk)
375 {
376 	return NULL;
377 }
378 
379 #define inet6_rcv_saddr(__sk)	NULL
380 #define tcp_twsk_ipv6only(__sk)		0
381 #define inet_v6_ipv6only(__sk)		0
382 #endif /* IS_ENABLED(CONFIG_IPV6) */
383 #endif /* _IPV6_H */
384