xref: /linux-6.15/include/linux/ipv6.h (revision dec102aa)
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_delay;
22 	__s32		force_mld_version;
23 	__s32		mldv1_unsolicited_report_interval;
24 	__s32		mldv2_unsolicited_report_interval;
25 	__s32		use_tempaddr;
26 	__s32		temp_valid_lft;
27 	__s32		temp_prefered_lft;
28 	__s32		regen_max_retry;
29 	__s32		max_desync_factor;
30 	__s32		max_addresses;
31 	__s32		accept_ra_defrtr;
32 	__s32		accept_ra_pinfo;
33 #ifdef CONFIG_IPV6_ROUTER_PREF
34 	__s32		accept_ra_rtr_pref;
35 	__s32		rtr_probe_interval;
36 #ifdef CONFIG_IPV6_ROUTE_INFO
37 	__s32		accept_ra_rt_info_max_plen;
38 #endif
39 #endif
40 	__s32		proxy_ndp;
41 	__s32		accept_source_route;
42 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
43 	__s32		optimistic_dad;
44 #endif
45 #ifdef CONFIG_IPV6_MROUTE
46 	__s32		mc_forwarding;
47 #endif
48 	__s32		disable_ipv6;
49 	__s32		accept_dad;
50 	__s32		force_tllao;
51 	__s32           ndisc_notify;
52 	__s32		suppress_frag_ndisc;
53 	void		*sysctl;
54 };
55 
56 struct ipv6_params {
57 	__s32 disable_ipv6;
58 	__s32 autoconf;
59 };
60 extern struct ipv6_params ipv6_defaults;
61 #include <linux/icmpv6.h>
62 #include <linux/tcp.h>
63 #include <linux/udp.h>
64 
65 #include <net/inet_sock.h>
66 
67 static inline struct ipv6hdr *ipv6_hdr(const struct sk_buff *skb)
68 {
69 	return (struct ipv6hdr *)skb_network_header(skb);
70 }
71 
72 static inline struct ipv6hdr *inner_ipv6_hdr(const struct sk_buff *skb)
73 {
74 	return (struct ipv6hdr *)skb_inner_network_header(skb);
75 }
76 
77 static inline struct ipv6hdr *ipipv6_hdr(const struct sk_buff *skb)
78 {
79 	return (struct ipv6hdr *)skb_transport_header(skb);
80 }
81 
82 /*
83    This structure contains results of exthdrs parsing
84    as offsets from skb->nh.
85  */
86 
87 struct inet6_skb_parm {
88 	int			iif;
89 	__be16			ra;
90 	__u16			hop;
91 	__u16			dst0;
92 	__u16			srcrt;
93 	__u16			dst1;
94 	__u16			lastopt;
95 	__u16			nhoff;
96 	__u16			flags;
97 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
98 	__u16			dsthao;
99 #endif
100 	__u16			frag_max_size;
101 
102 #define IP6SKB_XFRM_TRANSFORMED	1
103 #define IP6SKB_FORWARDED	2
104 #define IP6SKB_REROUTED		4
105 #define IP6SKB_ROUTERALERT	8
106 #define IP6SKB_FRAGMENTED      16
107 };
108 
109 #define IP6CB(skb)	((struct inet6_skb_parm*)((skb)->cb))
110 #define IP6CBMTU(skb)	((struct ip6_mtuinfo *)((skb)->cb))
111 
112 static inline int inet6_iif(const struct sk_buff *skb)
113 {
114 	return IP6CB(skb)->iif;
115 }
116 
117 struct tcp6_request_sock {
118 	struct tcp_request_sock	  tcp6rsk_tcp;
119 };
120 
121 struct ipv6_mc_socklist;
122 struct ipv6_ac_socklist;
123 struct ipv6_fl_socklist;
124 
125 /**
126  * struct ipv6_pinfo - ipv6 private area
127  *
128  * In the struct sock hierarchy (tcp6_sock, upd6_sock, etc)
129  * this _must_ be the last member, so that inet6_sk_generic
130  * is able to calculate its offset from the base struct sock
131  * by using the struct proto->slab_obj_size member. -acme
132  */
133 struct ipv6_pinfo {
134 	struct in6_addr 	saddr;
135 	struct in6_pktinfo	sticky_pktinfo;
136 	const struct in6_addr		*daddr_cache;
137 #ifdef CONFIG_IPV6_SUBTREES
138 	const struct in6_addr		*saddr_cache;
139 #endif
140 
141 	__be32			flow_label;
142 	__u32			frag_size;
143 
144 	/*
145 	 * Packed in 16bits.
146 	 * Omit one shift by by putting the signed field at MSB.
147 	 */
148 #if defined(__BIG_ENDIAN_BITFIELD)
149 	__s16			hop_limit:9;
150 	__u16			__unused_1:7;
151 #else
152 	__u16			__unused_1:7;
153 	__s16			hop_limit:9;
154 #endif
155 
156 #if defined(__BIG_ENDIAN_BITFIELD)
157 	/* Packed in 16bits. */
158 	__s16			mcast_hops:9;
159 	__u16			__unused_2:6,
160 				mc_loop:1;
161 #else
162 	__u16			mc_loop:1,
163 				__unused_2:6;
164 	__s16			mcast_hops:9;
165 #endif
166 	int			ucast_oif;
167 	int			mcast_oif;
168 
169 	/* pktoption flags */
170 	union {
171 		struct {
172 			__u16	srcrt:1,
173 				osrcrt:1,
174 			        rxinfo:1,
175 			        rxoinfo:1,
176 				rxhlim:1,
177 				rxohlim:1,
178 				hopopts:1,
179 				ohopopts:1,
180 				dstopts:1,
181 				odstopts:1,
182                                 rxflow:1,
183 				rxtclass:1,
184 				rxpmtu:1,
185 				rxorigdstaddr:1;
186 				/* 2 bits hole */
187 		} bits;
188 		__u16		all;
189 	} rxopt;
190 
191 	/* sockopt flags */
192 	__u16			recverr:1,
193 	                        sndflow:1,
194 				repflow:1,
195 				pmtudisc:3,
196 				ipv6only:1,
197 				srcprefs:3,	/* 001: prefer temporary address
198 						 * 010: prefer public address
199 						 * 100: prefer care-of address
200 						 */
201 				dontfrag:1;
202 	__u8			min_hopcount;
203 	__u8			tclass;
204 	__be32			rcv_flowinfo;
205 
206 	__u32			dst_cookie;
207 	__u32			rx_dst_cookie;
208 
209 	struct ipv6_mc_socklist	__rcu *ipv6_mc_list;
210 	struct ipv6_ac_socklist	*ipv6_ac_list;
211 	struct ipv6_fl_socklist __rcu *ipv6_fl_list;
212 
213 	struct ipv6_txoptions	*opt;
214 	struct sk_buff		*pktoptions;
215 	struct sk_buff		*rxpmtu;
216 	struct {
217 		struct ipv6_txoptions *opt;
218 		u8 hop_limit;
219 		u8 tclass;
220 	} cork;
221 };
222 
223 /* WARNING: don't change the layout of the members in {raw,udp,tcp}6_sock! */
224 struct raw6_sock {
225 	/* inet_sock has to be the first member of raw6_sock */
226 	struct inet_sock	inet;
227 	__u32			checksum;	/* perform checksum */
228 	__u32			offset;		/* checksum offset  */
229 	struct icmp6_filter	filter;
230 	__u32			ip6mr_table;
231 	/* ipv6_pinfo has to be the last member of raw6_sock, see inet6_sk_generic */
232 	struct ipv6_pinfo	inet6;
233 };
234 
235 struct udp6_sock {
236 	struct udp_sock	  udp;
237 	/* ipv6_pinfo has to be the last member of udp6_sock, see inet6_sk_generic */
238 	struct ipv6_pinfo inet6;
239 };
240 
241 struct tcp6_sock {
242 	struct tcp_sock	  tcp;
243 	/* ipv6_pinfo has to be the last member of tcp6_sock, see inet6_sk_generic */
244 	struct ipv6_pinfo inet6;
245 };
246 
247 extern int inet6_sk_rebuild_header(struct sock *sk);
248 
249 struct tcp6_timewait_sock {
250 	struct tcp_timewait_sock   tcp6tw_tcp;
251 };
252 
253 #if IS_ENABLED(CONFIG_IPV6)
254 static inline struct ipv6_pinfo * inet6_sk(const struct sock *__sk)
255 {
256 	return inet_sk(__sk)->pinet6;
257 }
258 
259 static inline struct request_sock *inet6_reqsk_alloc(struct request_sock_ops *ops)
260 {
261 	struct request_sock *req = reqsk_alloc(ops);
262 
263 	if (req)
264 		inet_rsk(req)->pktopts = NULL;
265 
266 	return req;
267 }
268 
269 static inline struct raw6_sock *raw6_sk(const struct sock *sk)
270 {
271 	return (struct raw6_sock *)sk;
272 }
273 
274 static inline void inet_sk_copy_descendant(struct sock *sk_to,
275 					   const struct sock *sk_from)
276 {
277 	int ancestor_size = sizeof(struct inet_sock);
278 
279 	if (sk_from->sk_family == PF_INET6)
280 		ancestor_size += sizeof(struct ipv6_pinfo);
281 
282 	__inet_sk_copy_descendant(sk_to, sk_from, ancestor_size);
283 }
284 
285 #define __ipv6_only_sock(sk)	(inet6_sk(sk)->ipv6only)
286 #define ipv6_only_sock(sk)	((sk)->sk_family == PF_INET6 && __ipv6_only_sock(sk))
287 #define ipv6_sk_rxinfo(sk)	((sk)->sk_family == PF_INET6 && \
288 				 inet6_sk(sk)->rxopt.bits.rxinfo)
289 
290 static inline const struct in6_addr *inet6_rcv_saddr(const struct sock *sk)
291 {
292 	if (sk->sk_family == AF_INET6)
293 		return &sk->sk_v6_rcv_saddr;
294 	return NULL;
295 }
296 
297 static inline int inet_v6_ipv6only(const struct sock *sk)
298 {
299 	return likely(sk->sk_state != TCP_TIME_WAIT) ?
300 		ipv6_only_sock(sk) : inet_twsk(sk)->tw_ipv6only;
301 }
302 #else
303 #define __ipv6_only_sock(sk)	0
304 #define ipv6_only_sock(sk)	0
305 #define ipv6_sk_rxinfo(sk)	0
306 
307 static inline struct ipv6_pinfo * inet6_sk(const struct sock *__sk)
308 {
309 	return NULL;
310 }
311 
312 static inline struct inet6_request_sock *
313 			inet6_rsk(const struct request_sock *rsk)
314 {
315 	return NULL;
316 }
317 
318 static inline struct raw6_sock *raw6_sk(const struct sock *sk)
319 {
320 	return NULL;
321 }
322 
323 #define inet6_rcv_saddr(__sk)	NULL
324 #define tcp_twsk_ipv6only(__sk)		0
325 #define inet_v6_ipv6only(__sk)		0
326 #endif /* IS_ENABLED(CONFIG_IPV6) */
327 
328 #define INET6_MATCH(__sk, __net, __saddr, __daddr, __ports, __dif)	\
329 	(((__sk)->sk_portpair == (__ports))			&&	\
330 	 ((__sk)->sk_family == AF_INET6)			&&	\
331 	 ipv6_addr_equal(&(__sk)->sk_v6_daddr, (__saddr))		&&	\
332 	 ipv6_addr_equal(&(__sk)->sk_v6_rcv_saddr, (__daddr))	&&	\
333 	 (!(__sk)->sk_bound_dev_if	||				\
334 	   ((__sk)->sk_bound_dev_if == (__dif))) 		&&	\
335 	 net_eq(sock_net(__sk), (__net)))
336 
337 #endif /* _IPV6_H */
338