xref: /linux-6.15/include/linux/ipv6.h (revision cee2cfb7)
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 	__s32		seg6_enabled;
68 #ifdef CONFIG_IPV6_SEG6_HMAC
69 	__s32		seg6_require_hmac;
70 #endif
71 	__u32		enhanced_dad;
72 
73 	struct ctl_table_header *sysctl_header;
74 };
75 
76 struct ipv6_params {
77 	__s32 disable_ipv6;
78 	__s32 autoconf;
79 };
80 extern struct ipv6_params ipv6_defaults;
81 #include <linux/icmpv6.h>
82 #include <linux/tcp.h>
83 #include <linux/udp.h>
84 
85 #include <net/inet_sock.h>
86 
87 static inline struct ipv6hdr *ipv6_hdr(const struct sk_buff *skb)
88 {
89 	return (struct ipv6hdr *)skb_network_header(skb);
90 }
91 
92 static inline struct ipv6hdr *inner_ipv6_hdr(const struct sk_buff *skb)
93 {
94 	return (struct ipv6hdr *)skb_inner_network_header(skb);
95 }
96 
97 static inline struct ipv6hdr *ipipv6_hdr(const struct sk_buff *skb)
98 {
99 	return (struct ipv6hdr *)skb_transport_header(skb);
100 }
101 
102 /*
103    This structure contains results of exthdrs parsing
104    as offsets from skb->nh.
105  */
106 
107 struct inet6_skb_parm {
108 	int			iif;
109 	__be16			ra;
110 	__u16			dst0;
111 	__u16			srcrt;
112 	__u16			dst1;
113 	__u16			lastopt;
114 	__u16			nhoff;
115 	__u16			flags;
116 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
117 	__u16			dsthao;
118 #endif
119 	__u16			frag_max_size;
120 
121 #define IP6SKB_XFRM_TRANSFORMED	1
122 #define IP6SKB_FORWARDED	2
123 #define IP6SKB_REROUTED		4
124 #define IP6SKB_ROUTERALERT	8
125 #define IP6SKB_FRAGMENTED      16
126 #define IP6SKB_HOPBYHOP        32
127 #define IP6SKB_L3SLAVE         64
128 };
129 
130 #if defined(CONFIG_NET_L3_MASTER_DEV)
131 static inline bool ipv6_l3mdev_skb(__u16 flags)
132 {
133 	return flags & IP6SKB_L3SLAVE;
134 }
135 #else
136 static inline bool ipv6_l3mdev_skb(__u16 flags)
137 {
138 	return false;
139 }
140 #endif
141 
142 #define IP6CB(skb)	((struct inet6_skb_parm*)((skb)->cb))
143 #define IP6CBMTU(skb)	((struct ip6_mtuinfo *)((skb)->cb))
144 
145 static inline int inet6_iif(const struct sk_buff *skb)
146 {
147 	bool l3_slave = ipv6_l3mdev_skb(IP6CB(skb)->flags);
148 
149 	return l3_slave ? skb->skb_iif : IP6CB(skb)->iif;
150 }
151 
152 /* can not be used in TCP layer after tcp_v6_fill_cb */
153 static inline bool inet6_exact_dif_match(struct net *net, struct sk_buff *skb)
154 {
155 #if defined(CONFIG_NET_L3_MASTER_DEV)
156 	if (!net->ipv4.sysctl_tcp_l3mdev_accept &&
157 	    skb && ipv6_l3mdev_skb(IP6CB(skb)->flags))
158 		return true;
159 #endif
160 	return false;
161 }
162 
163 struct tcp6_request_sock {
164 	struct tcp_request_sock	  tcp6rsk_tcp;
165 };
166 
167 struct ipv6_mc_socklist;
168 struct ipv6_ac_socklist;
169 struct ipv6_fl_socklist;
170 
171 struct inet6_cork {
172 	struct ipv6_txoptions *opt;
173 	u8 hop_limit;
174 	u8 tclass;
175 };
176 
177 /**
178  * struct ipv6_pinfo - ipv6 private area
179  *
180  * In the struct sock hierarchy (tcp6_sock, upd6_sock, etc)
181  * this _must_ be the last member, so that inet6_sk_generic
182  * is able to calculate its offset from the base struct sock
183  * by using the struct proto->slab_obj_size member. -acme
184  */
185 struct ipv6_pinfo {
186 	struct in6_addr 	saddr;
187 	struct in6_pktinfo	sticky_pktinfo;
188 	const struct in6_addr		*daddr_cache;
189 #ifdef CONFIG_IPV6_SUBTREES
190 	const struct in6_addr		*saddr_cache;
191 #endif
192 
193 	__be32			flow_label;
194 	__u32			frag_size;
195 
196 	/*
197 	 * Packed in 16bits.
198 	 * Omit one shift by by putting the signed field at MSB.
199 	 */
200 #if defined(__BIG_ENDIAN_BITFIELD)
201 	__s16			hop_limit:9;
202 	__u16			__unused_1:7;
203 #else
204 	__u16			__unused_1:7;
205 	__s16			hop_limit:9;
206 #endif
207 
208 #if defined(__BIG_ENDIAN_BITFIELD)
209 	/* Packed in 16bits. */
210 	__s16			mcast_hops:9;
211 	__u16			__unused_2:6,
212 				mc_loop:1;
213 #else
214 	__u16			mc_loop:1,
215 				__unused_2:6;
216 	__s16			mcast_hops:9;
217 #endif
218 	int			ucast_oif;
219 	int			mcast_oif;
220 
221 	/* pktoption flags */
222 	union {
223 		struct {
224 			__u16	srcrt:1,
225 				osrcrt:1,
226 			        rxinfo:1,
227 			        rxoinfo:1,
228 				rxhlim:1,
229 				rxohlim:1,
230 				hopopts:1,
231 				ohopopts:1,
232 				dstopts:1,
233 				odstopts:1,
234                                 rxflow:1,
235 				rxtclass:1,
236 				rxpmtu:1,
237 				rxorigdstaddr:1,
238 				recvfragsize:1;
239 				/* 1 bits hole */
240 		} bits;
241 		__u16		all;
242 	} rxopt;
243 
244 	/* sockopt flags */
245 	__u16			recverr:1,
246 	                        sndflow:1,
247 				repflow:1,
248 				pmtudisc:3,
249 				padding:1,	/* 1 bit hole */
250 				srcprefs:3,	/* 001: prefer temporary address
251 						 * 010: prefer public address
252 						 * 100: prefer care-of address
253 						 */
254 				dontfrag:1,
255 				autoflowlabel:1;
256 	__u8			min_hopcount;
257 	__u8			tclass;
258 	__be32			rcv_flowinfo;
259 
260 	__u32			dst_cookie;
261 	__u32			rx_dst_cookie;
262 
263 	struct ipv6_mc_socklist	__rcu *ipv6_mc_list;
264 	struct ipv6_ac_socklist	*ipv6_ac_list;
265 	struct ipv6_fl_socklist __rcu *ipv6_fl_list;
266 
267 	struct ipv6_txoptions __rcu	*opt;
268 	struct sk_buff		*pktoptions;
269 	struct sk_buff		*rxpmtu;
270 	struct inet6_cork	cork;
271 };
272 
273 /* WARNING: don't change the layout of the members in {raw,udp,tcp}6_sock! */
274 struct raw6_sock {
275 	/* inet_sock has to be the first member of raw6_sock */
276 	struct inet_sock	inet;
277 	__u32			checksum;	/* perform checksum */
278 	__u32			offset;		/* checksum offset  */
279 	struct icmp6_filter	filter;
280 	__u32			ip6mr_table;
281 	/* ipv6_pinfo has to be the last member of raw6_sock, see inet6_sk_generic */
282 	struct ipv6_pinfo	inet6;
283 };
284 
285 struct udp6_sock {
286 	struct udp_sock	  udp;
287 	/* ipv6_pinfo has to be the last member of udp6_sock, see inet6_sk_generic */
288 	struct ipv6_pinfo inet6;
289 };
290 
291 struct tcp6_sock {
292 	struct tcp_sock	  tcp;
293 	/* ipv6_pinfo has to be the last member of tcp6_sock, see inet6_sk_generic */
294 	struct ipv6_pinfo inet6;
295 };
296 
297 extern int inet6_sk_rebuild_header(struct sock *sk);
298 
299 struct tcp6_timewait_sock {
300 	struct tcp_timewait_sock   tcp6tw_tcp;
301 };
302 
303 #if IS_ENABLED(CONFIG_IPV6)
304 bool ipv6_mod_enabled(void);
305 
306 static inline struct ipv6_pinfo *inet6_sk(const struct sock *__sk)
307 {
308 	return sk_fullsock(__sk) ? inet_sk(__sk)->pinet6 : NULL;
309 }
310 
311 static inline struct raw6_sock *raw6_sk(const struct sock *sk)
312 {
313 	return (struct raw6_sock *)sk;
314 }
315 
316 static inline void inet_sk_copy_descendant(struct sock *sk_to,
317 					   const struct sock *sk_from)
318 {
319 	int ancestor_size = sizeof(struct inet_sock);
320 
321 	if (sk_from->sk_family == PF_INET6)
322 		ancestor_size += sizeof(struct ipv6_pinfo);
323 
324 	__inet_sk_copy_descendant(sk_to, sk_from, ancestor_size);
325 }
326 
327 #define __ipv6_only_sock(sk)	(sk->sk_ipv6only)
328 #define ipv6_only_sock(sk)	(__ipv6_only_sock(sk))
329 #define ipv6_sk_rxinfo(sk)	((sk)->sk_family == PF_INET6 && \
330 				 inet6_sk(sk)->rxopt.bits.rxinfo)
331 
332 static inline const struct in6_addr *inet6_rcv_saddr(const struct sock *sk)
333 {
334 	if (sk->sk_family == AF_INET6)
335 		return &sk->sk_v6_rcv_saddr;
336 	return NULL;
337 }
338 
339 static inline int inet_v6_ipv6only(const struct sock *sk)
340 {
341 	/* ipv6only field is at same position for timewait and other sockets */
342 	return ipv6_only_sock(sk);
343 }
344 #else
345 #define __ipv6_only_sock(sk)	0
346 #define ipv6_only_sock(sk)	0
347 #define ipv6_sk_rxinfo(sk)	0
348 
349 static inline bool ipv6_mod_enabled(void)
350 {
351 	return false;
352 }
353 
354 static inline struct ipv6_pinfo * inet6_sk(const struct sock *__sk)
355 {
356 	return NULL;
357 }
358 
359 static inline struct inet6_request_sock *
360 			inet6_rsk(const struct request_sock *rsk)
361 {
362 	return NULL;
363 }
364 
365 static inline struct raw6_sock *raw6_sk(const struct sock *sk)
366 {
367 	return NULL;
368 }
369 
370 #define inet6_rcv_saddr(__sk)	NULL
371 #define tcp_twsk_ipv6only(__sk)		0
372 #define inet_v6_ipv6only(__sk)		0
373 #endif /* IS_ENABLED(CONFIG_IPV6) */
374 #endif /* _IPV6_H */
375