xref: /linux-6.15/include/linux/ipv6.h (revision 1da177e4)
1 #ifndef _IPV6_H
2 #define _IPV6_H
3 
4 #include <linux/config.h>
5 #include <linux/in6.h>
6 #include <asm/byteorder.h>
7 
8 /* The latest drafts declared increase in minimal mtu up to 1280. */
9 
10 #define IPV6_MIN_MTU	1280
11 
12 /*
13  *	Advanced API
14  *	source interface/address selection, source routing, etc...
15  *	*under construction*
16  */
17 
18 
19 struct in6_pktinfo {
20 	struct in6_addr	ipi6_addr;
21 	int		ipi6_ifindex;
22 };
23 
24 
25 struct in6_ifreq {
26 	struct in6_addr	ifr6_addr;
27 	__u32		ifr6_prefixlen;
28 	int		ifr6_ifindex;
29 };
30 
31 #define IPV6_SRCRT_STRICT	0x01	/* this hop must be a neighbor	*/
32 #define IPV6_SRCRT_TYPE_0	0	/* IPv6 type 0 Routing Header	*/
33 
34 /*
35  *	routing header
36  */
37 struct ipv6_rt_hdr {
38 	__u8		nexthdr;
39 	__u8		hdrlen;
40 	__u8		type;
41 	__u8		segments_left;
42 
43 	/*
44 	 *	type specific data
45 	 *	variable length field
46 	 */
47 };
48 
49 
50 struct ipv6_opt_hdr {
51 	__u8 		nexthdr;
52 	__u8 		hdrlen;
53 	/*
54 	 * TLV encoded option data follows.
55 	 */
56 };
57 
58 #define ipv6_destopt_hdr ipv6_opt_hdr
59 #define ipv6_hopopt_hdr  ipv6_opt_hdr
60 
61 #ifdef __KERNEL__
62 #define ipv6_optlen(p)  (((p)->hdrlen+1) << 3)
63 #endif
64 
65 /*
66  *	routing header type 0 (used in cmsghdr struct)
67  */
68 
69 struct rt0_hdr {
70 	struct ipv6_rt_hdr	rt_hdr;
71 	__u32			bitmap;		/* strict/loose bit map */
72 	struct in6_addr		addr[0];
73 
74 #define rt0_type		rt_hdr.type
75 };
76 
77 struct ipv6_auth_hdr {
78 	__u8  nexthdr;
79 	__u8  hdrlen;           /* This one is measured in 32 bit units! */
80 	__u16 reserved;
81 	__u32 spi;
82 	__u32 seq_no;           /* Sequence number */
83 	__u8  auth_data[0];     /* Length variable but >=4. Mind the 64 bit alignment! */
84 };
85 
86 struct ipv6_esp_hdr {
87 	__u32 spi;
88 	__u32 seq_no;           /* Sequence number */
89 	__u8  enc_data[0];      /* Length variable but >=8. Mind the 64 bit alignment! */
90 };
91 
92 struct ipv6_comp_hdr {
93 	__u8 nexthdr;
94 	__u8 flags;
95 	__u16 cpi;
96 };
97 
98 /*
99  *	IPv6 fixed header
100  *
101  *	BEWARE, it is incorrect. The first 4 bits of flow_lbl
102  *	are glued to priority now, forming "class".
103  */
104 
105 struct ipv6hdr {
106 #if defined(__LITTLE_ENDIAN_BITFIELD)
107 	__u8			priority:4,
108 				version:4;
109 #elif defined(__BIG_ENDIAN_BITFIELD)
110 	__u8			version:4,
111 				priority:4;
112 #else
113 #error	"Please fix <asm/byteorder.h>"
114 #endif
115 	__u8			flow_lbl[3];
116 
117 	__u16			payload_len;
118 	__u8			nexthdr;
119 	__u8			hop_limit;
120 
121 	struct	in6_addr	saddr;
122 	struct	in6_addr	daddr;
123 };
124 
125 /*
126  * This structure contains configuration options per IPv6 link.
127  */
128 struct ipv6_devconf {
129 	__s32		forwarding;
130 	__s32		hop_limit;
131 	__s32		mtu6;
132 	__s32		accept_ra;
133 	__s32		accept_redirects;
134 	__s32		autoconf;
135 	__s32		dad_transmits;
136 	__s32		rtr_solicits;
137 	__s32		rtr_solicit_interval;
138 	__s32		rtr_solicit_delay;
139 	__s32		force_mld_version;
140 #ifdef CONFIG_IPV6_PRIVACY
141 	__s32		use_tempaddr;
142 	__s32		temp_valid_lft;
143 	__s32		temp_prefered_lft;
144 	__s32		regen_max_retry;
145 	__s32		max_desync_factor;
146 #endif
147 	__s32		max_addresses;
148 	void		*sysctl;
149 };
150 
151 /* index values for the variables in ipv6_devconf */
152 enum {
153 	DEVCONF_FORWARDING = 0,
154 	DEVCONF_HOPLIMIT,
155 	DEVCONF_MTU6,
156 	DEVCONF_ACCEPT_RA,
157 	DEVCONF_ACCEPT_REDIRECTS,
158 	DEVCONF_AUTOCONF,
159 	DEVCONF_DAD_TRANSMITS,
160 	DEVCONF_RTR_SOLICITS,
161 	DEVCONF_RTR_SOLICIT_INTERVAL,
162 	DEVCONF_RTR_SOLICIT_DELAY,
163 	DEVCONF_USE_TEMPADDR,
164 	DEVCONF_TEMP_VALID_LFT,
165 	DEVCONF_TEMP_PREFERED_LFT,
166 	DEVCONF_REGEN_MAX_RETRY,
167 	DEVCONF_MAX_DESYNC_FACTOR,
168 	DEVCONF_MAX_ADDRESSES,
169 	DEVCONF_FORCE_MLD_VERSION,
170 	DEVCONF_MAX
171 };
172 
173 #ifdef __KERNEL__
174 #include <linux/in6.h>          /* struct sockaddr_in6 */
175 #include <linux/icmpv6.h>
176 #include <net/if_inet6.h>       /* struct ipv6_mc_socklist */
177 #include <linux/tcp.h>
178 #include <linux/udp.h>
179 
180 /*
181    This structure contains results of exthdrs parsing
182    as offsets from skb->nh.
183  */
184 
185 struct inet6_skb_parm {
186 	int			iif;
187 	__u16			ra;
188 	__u16			hop;
189 	__u16			dst0;
190 	__u16			srcrt;
191 	__u16			dst1;
192 };
193 
194 #define IP6CB(skb)	((struct inet6_skb_parm*)((skb)->cb))
195 
196 /**
197  * struct ipv6_pinfo - ipv6 private area
198  *
199  * In the struct sock hierarchy (tcp6_sock, upd6_sock, etc)
200  * this _must_ be the last member, so that inet6_sk_generic
201  * is able to calculate its offset from the base struct sock
202  * by using the struct proto->slab_obj_size member. -acme
203  */
204 struct ipv6_pinfo {
205 	struct in6_addr 	saddr;
206 	struct in6_addr 	rcv_saddr;
207 	struct in6_addr		daddr;
208 	struct in6_addr		*daddr_cache;
209 
210 	__u32			flow_label;
211 	__u32			frag_size;
212 	__s16			hop_limit;
213 	__s16			mcast_hops;
214 	int			mcast_oif;
215 
216 	/* pktoption flags */
217 	union {
218 		struct {
219 			__u8	srcrt:2,
220 			        rxinfo:1,
221 				rxhlim:1,
222 				hopopts:1,
223 				dstopts:1,
224                                 rxflow:1;
225 		} bits;
226 		__u8		all;
227 	} rxopt;
228 
229 	/* sockopt flags */
230 	__u8			mc_loop:1,
231 	                        recverr:1,
232 	                        sndflow:1,
233 				pmtudisc:2,
234 				ipv6only:1;
235 
236 	__u32			dst_cookie;
237 
238 	struct ipv6_mc_socklist	*ipv6_mc_list;
239 	struct ipv6_ac_socklist	*ipv6_ac_list;
240 	struct ipv6_fl_socklist *ipv6_fl_list;
241 
242 	struct ipv6_txoptions	*opt;
243 	struct sk_buff		*pktoptions;
244 	struct {
245 		struct ipv6_txoptions *opt;
246 		struct rt6_info	*rt;
247 		int hop_limit;
248 	} cork;
249 };
250 
251 /* WARNING: don't change the layout of the members in {raw,udp,tcp}6_sock! */
252 struct raw6_sock {
253 	/* inet_sock has to be the first member of raw6_sock */
254 	struct inet_sock	inet;
255 	__u32			checksum;	/* perform checksum */
256 	__u32			offset;		/* checksum offset  */
257 	struct icmp6_filter	filter;
258 	/* ipv6_pinfo has to be the last member of raw6_sock, see inet6_sk_generic */
259 	struct ipv6_pinfo	inet6;
260 };
261 
262 struct udp6_sock {
263 	struct udp_sock	  udp;
264 	/* ipv6_pinfo has to be the last member of udp6_sock, see inet6_sk_generic */
265 	struct ipv6_pinfo inet6;
266 };
267 
268 struct tcp6_sock {
269 	struct tcp_sock	  tcp;
270 	/* ipv6_pinfo has to be the last member of tcp6_sock, see inet6_sk_generic */
271 	struct ipv6_pinfo inet6;
272 };
273 
274 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
275 static inline struct ipv6_pinfo * inet6_sk(const struct sock *__sk)
276 {
277 	return inet_sk(__sk)->pinet6;
278 }
279 
280 static inline struct raw6_sock *raw6_sk(const struct sock *sk)
281 {
282 	return (struct raw6_sock *)sk;
283 }
284 
285 static inline void inet_sk_copy_descendant(struct sock *sk_to,
286 					   const struct sock *sk_from)
287 {
288 	int ancestor_size = sizeof(struct inet_sock);
289 
290 	if (sk_from->sk_family == PF_INET6)
291 		ancestor_size += sizeof(struct ipv6_pinfo);
292 
293 	__inet_sk_copy_descendant(sk_to, sk_from, ancestor_size);
294 }
295 
296 #define __ipv6_only_sock(sk)	(inet6_sk(sk)->ipv6only)
297 #define ipv6_only_sock(sk)	((sk)->sk_family == PF_INET6 && __ipv6_only_sock(sk))
298 #else
299 #define __ipv6_only_sock(sk)	0
300 #define ipv6_only_sock(sk)	0
301 
302 static inline struct ipv6_pinfo * inet6_sk(const struct sock *__sk)
303 {
304 	return NULL;
305 }
306 
307 static inline struct raw6_sock *raw6_sk(const struct sock *sk)
308 {
309 	return NULL;
310 }
311 
312 #endif
313 
314 #endif
315 
316 #endif
317