xref: /linux/include/net/ipv6.h (revision f3d9478b2ce468c3115b02ecae7e975990697f15)
1 /*
2  *	Linux INET6 implementation
3  *
4  *	Authors:
5  *	Pedro Roque		<roque@di.fc.ul.pt>
6  *
7  *	$Id: ipv6.h,v 1.1 2002/05/20 15:13:07 jgrimm Exp $
8  *
9  *	This program is free software; you can redistribute it and/or
10  *      modify it under the terms of the GNU General Public License
11  *      as published by the Free Software Foundation; either version
12  *      2 of the License, or (at your option) any later version.
13  */
14 
15 #ifndef _NET_IPV6_H
16 #define _NET_IPV6_H
17 
18 #include <linux/ipv6.h>
19 #include <linux/hardirq.h>
20 #include <net/ndisc.h>
21 #include <net/flow.h>
22 #include <net/snmp.h>
23 
24 #define SIN6_LEN_RFC2133	24
25 
26 #define IPV6_MAXPLEN		65535
27 
28 /*
29  *	NextHeader field of IPv6 header
30  */
31 
32 #define NEXTHDR_HOP		0	/* Hop-by-hop option header. */
33 #define NEXTHDR_TCP		6	/* TCP segment. */
34 #define NEXTHDR_UDP		17	/* UDP message. */
35 #define NEXTHDR_IPV6		41	/* IPv6 in IPv6 */
36 #define NEXTHDR_ROUTING		43	/* Routing header. */
37 #define NEXTHDR_FRAGMENT	44	/* Fragmentation/reassembly header. */
38 #define NEXTHDR_ESP		50	/* Encapsulating security payload. */
39 #define NEXTHDR_AUTH		51	/* Authentication header. */
40 #define NEXTHDR_ICMP		58	/* ICMP for IPv6. */
41 #define NEXTHDR_NONE		59	/* No next header */
42 #define NEXTHDR_DEST		60	/* Destination options header. */
43 
44 #define NEXTHDR_MAX		255
45 
46 
47 
48 #define IPV6_DEFAULT_HOPLIMIT   64
49 #define IPV6_DEFAULT_MCASTHOPS	1
50 
51 /*
52  *	Addr type
53  *
54  *	type	-	unicast | multicast
55  *	scope	-	local	| site	    | global
56  *	v4	-	compat
57  *	v4mapped
58  *	any
59  *	loopback
60  */
61 
62 #define IPV6_ADDR_ANY		0x0000U
63 
64 #define IPV6_ADDR_UNICAST      	0x0001U
65 #define IPV6_ADDR_MULTICAST    	0x0002U
66 
67 #define IPV6_ADDR_LOOPBACK	0x0010U
68 #define IPV6_ADDR_LINKLOCAL	0x0020U
69 #define IPV6_ADDR_SITELOCAL	0x0040U
70 
71 #define IPV6_ADDR_COMPATv4	0x0080U
72 
73 #define IPV6_ADDR_SCOPE_MASK	0x00f0U
74 
75 #define IPV6_ADDR_MAPPED	0x1000U
76 #define IPV6_ADDR_RESERVED	0x2000U	/* reserved address space */
77 
78 /*
79  *	Addr scopes
80  */
81 #ifdef __KERNEL__
82 #define IPV6_ADDR_MC_SCOPE(a)	\
83 	((a)->s6_addr[1] & 0x0f)	/* nonstandard */
84 #define __IPV6_ADDR_SCOPE_INVALID	-1
85 #endif
86 #define IPV6_ADDR_SCOPE_NODELOCAL	0x01
87 #define IPV6_ADDR_SCOPE_LINKLOCAL	0x02
88 #define IPV6_ADDR_SCOPE_SITELOCAL	0x05
89 #define IPV6_ADDR_SCOPE_ORGLOCAL	0x08
90 #define IPV6_ADDR_SCOPE_GLOBAL		0x0e
91 
92 /*
93  *	fragmentation header
94  */
95 
96 struct frag_hdr {
97 	unsigned char	nexthdr;
98 	unsigned char	reserved;
99 	unsigned short	frag_off;
100 	__u32		identification;
101 };
102 
103 #define	IP6_MF	0x0001
104 
105 #ifdef __KERNEL__
106 
107 #include <net/sock.h>
108 
109 /* sysctls */
110 extern int sysctl_ipv6_bindv6only;
111 extern int sysctl_mld_max_msf;
112 
113 /* MIBs */
114 DECLARE_SNMP_STAT(struct ipstats_mib, ipv6_statistics);
115 #define IP6_INC_STATS(field)		SNMP_INC_STATS(ipv6_statistics, field)
116 #define IP6_INC_STATS_BH(field)		SNMP_INC_STATS_BH(ipv6_statistics, field)
117 #define IP6_INC_STATS_USER(field) 	SNMP_INC_STATS_USER(ipv6_statistics, field)
118 DECLARE_SNMP_STAT(struct icmpv6_mib, icmpv6_statistics);
119 #define ICMP6_INC_STATS(idev, field)		({			\
120 	struct inet6_dev *_idev = (idev);				\
121 	if (likely(_idev != NULL))					\
122 		SNMP_INC_STATS(idev->stats.icmpv6, field); 		\
123 	SNMP_INC_STATS(icmpv6_statistics, field);			\
124 })
125 #define ICMP6_INC_STATS_BH(idev, field)		({			\
126 	struct inet6_dev *_idev = (idev);				\
127 	if (likely(_idev != NULL))					\
128 		SNMP_INC_STATS_BH((_idev)->stats.icmpv6, field);	\
129 	SNMP_INC_STATS_BH(icmpv6_statistics, field);			\
130 })
131 #define ICMP6_INC_STATS_USER(idev, field) 	({			\
132 	struct inet6_dev *_idev = (idev);				\
133 	if (likely(_idev != NULL))					\
134 		SNMP_INC_STATS_USER(_idev->stats.icmpv6, field);	\
135 	SNMP_INC_STATS_USER(icmpv6_statistics, field);			\
136 })
137 #define ICMP6_INC_STATS_OFFSET_BH(idev, field, offset)	({			\
138 	struct inet6_dev *_idev = idev;						\
139 	__typeof__(offset) _offset = (offset);					\
140 	if (likely(_idev != NULL))						\
141 		SNMP_INC_STATS_OFFSET_BH(_idev->stats.icmpv6, field, _offset);	\
142 	SNMP_INC_STATS_OFFSET_BH(icmpv6_statistics, field, _offset);    	\
143 })
144 DECLARE_SNMP_STAT(struct udp_mib, udp_stats_in6);
145 #define UDP6_INC_STATS(field)		SNMP_INC_STATS(udp_stats_in6, field)
146 #define UDP6_INC_STATS_BH(field)	SNMP_INC_STATS_BH(udp_stats_in6, field)
147 #define UDP6_INC_STATS_USER(field) 	SNMP_INC_STATS_USER(udp_stats_in6, field)
148 
149 int snmp6_register_dev(struct inet6_dev *idev);
150 int snmp6_unregister_dev(struct inet6_dev *idev);
151 int snmp6_alloc_dev(struct inet6_dev *idev);
152 int snmp6_free_dev(struct inet6_dev *idev);
153 int snmp6_mib_init(void *ptr[2], size_t mibsize, size_t mibalign);
154 void snmp6_mib_free(void *ptr[2]);
155 
156 struct ip6_ra_chain
157 {
158 	struct ip6_ra_chain	*next;
159 	struct sock		*sk;
160 	int			sel;
161 	void			(*destructor)(struct sock *);
162 };
163 
164 extern struct ip6_ra_chain	*ip6_ra_chain;
165 extern rwlock_t ip6_ra_lock;
166 
167 /*
168    This structure is prepared by protocol, when parsing
169    ancillary data and passed to IPv6.
170  */
171 
172 struct ipv6_txoptions
173 {
174 	/* Length of this structure */
175 	int			tot_len;
176 
177 	/* length of extension headers   */
178 
179 	__u16			opt_flen;	/* after fragment hdr */
180 	__u16			opt_nflen;	/* before fragment hdr */
181 
182 	struct ipv6_opt_hdr	*hopopt;
183 	struct ipv6_opt_hdr	*dst0opt;
184 	struct ipv6_rt_hdr	*srcrt;	/* Routing Header */
185 	struct ipv6_opt_hdr	*dst1opt;
186 
187 	/* Option buffer, as read by IPV6_PKTOPTIONS, starts here. */
188 };
189 
190 struct ip6_flowlabel
191 {
192 	struct ip6_flowlabel	*next;
193 	u32			label;
194 	struct in6_addr		dst;
195 	struct ipv6_txoptions	*opt;
196 	atomic_t		users;
197 	unsigned long		linger;
198 	u8			share;
199 	u32			owner;
200 	unsigned long		lastuse;
201 	unsigned long		expires;
202 };
203 
204 #define IPV6_FLOWINFO_MASK	__constant_htonl(0x0FFFFFFF)
205 #define IPV6_FLOWLABEL_MASK	__constant_htonl(0x000FFFFF)
206 
207 struct ipv6_fl_socklist
208 {
209 	struct ipv6_fl_socklist	*next;
210 	struct ip6_flowlabel	*fl;
211 };
212 
213 extern struct ip6_flowlabel	*fl6_sock_lookup(struct sock *sk, u32 label);
214 extern struct ipv6_txoptions	*fl6_merge_options(struct ipv6_txoptions * opt_space,
215 						   struct ip6_flowlabel * fl,
216 						   struct ipv6_txoptions * fopt);
217 extern void			fl6_free_socklist(struct sock *sk);
218 extern int			ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen);
219 extern void			ip6_flowlabel_init(void);
220 extern void			ip6_flowlabel_cleanup(void);
221 
222 static inline void fl6_sock_release(struct ip6_flowlabel *fl)
223 {
224 	if (fl)
225 		atomic_dec(&fl->users);
226 }
227 
228 extern int 			ip6_ra_control(struct sock *sk, int sel,
229 					       void (*destructor)(struct sock *));
230 
231 
232 extern int			ipv6_parse_hopopts(struct sk_buff *skb);
233 
234 extern struct ipv6_txoptions *  ipv6_dup_options(struct sock *sk, struct ipv6_txoptions *opt);
235 extern struct ipv6_txoptions *	ipv6_renew_options(struct sock *sk, struct ipv6_txoptions *opt,
236 						   int newtype,
237 						   struct ipv6_opt_hdr __user *newopt,
238 						   int newoptlen);
239 struct ipv6_txoptions *ipv6_fixup_options(struct ipv6_txoptions *opt_space,
240 					  struct ipv6_txoptions *opt);
241 
242 extern int ipv6_opt_accepted(struct sock *sk, struct sk_buff *skb);
243 
244 extern int ip6_frag_nqueues;
245 extern atomic_t ip6_frag_mem;
246 
247 #define IPV6_FRAG_TIMEOUT	(60*HZ)		/* 60 seconds */
248 
249 /*
250  *	Function prototype for build_xmit
251  */
252 
253 typedef int		(*inet_getfrag_t) (const void *data,
254 					   struct in6_addr *addr,
255 					   char *,
256 					   unsigned int, unsigned int);
257 
258 extern int __ipv6_addr_type(const struct in6_addr *addr);
259 static inline int ipv6_addr_type(const struct in6_addr *addr)
260 {
261 	return __ipv6_addr_type(addr) & 0xffff;
262 }
263 
264 static inline int ipv6_addr_scope(const struct in6_addr *addr)
265 {
266 	return __ipv6_addr_type(addr) & IPV6_ADDR_SCOPE_MASK;
267 }
268 
269 static inline int __ipv6_addr_src_scope(int type)
270 {
271 	return (type == IPV6_ADDR_ANY ? __IPV6_ADDR_SCOPE_INVALID : (type >> 16));
272 }
273 
274 static inline int ipv6_addr_src_scope(const struct in6_addr *addr)
275 {
276 	return __ipv6_addr_src_scope(__ipv6_addr_type(addr));
277 }
278 
279 static inline int ipv6_addr_cmp(const struct in6_addr *a1, const struct in6_addr *a2)
280 {
281 	return memcmp((const void *) a1, (const void *) a2, sizeof(struct in6_addr));
282 }
283 
284 static inline int
285 ipv6_masked_addr_cmp(const struct in6_addr *a1, const struct in6_addr *m,
286 		     const struct in6_addr *a2)
287 {
288 	unsigned int i;
289 
290 	for (i = 0; i < 4; i++)
291 		if ((a1->s6_addr32[i] ^ a2->s6_addr32[i]) & m->s6_addr32[i])
292 			return 1;
293 	return 0;
294 }
295 
296 static inline void ipv6_addr_copy(struct in6_addr *a1, const struct in6_addr *a2)
297 {
298 	memcpy((void *) a1, (const void *) a2, sizeof(struct in6_addr));
299 }
300 
301 static inline void ipv6_addr_prefix(struct in6_addr *pfx,
302 				    const struct in6_addr *addr,
303 				    int plen)
304 {
305 	/* caller must guarantee 0 <= plen <= 128 */
306 	int o = plen >> 3,
307 	    b = plen & 0x7;
308 
309 	memcpy(pfx->s6_addr, addr, o);
310 	if (b != 0) {
311 		pfx->s6_addr[o] = addr->s6_addr[o] & (0xff00 >> b);
312 		o++;
313 	}
314 	if (o < 16)
315 		memset(pfx->s6_addr + o, 0, 16 - o);
316 }
317 
318 #ifndef __HAVE_ARCH_ADDR_SET
319 static inline void ipv6_addr_set(struct in6_addr *addr,
320 				     __u32 w1, __u32 w2,
321 				     __u32 w3, __u32 w4)
322 {
323 	addr->s6_addr32[0] = w1;
324 	addr->s6_addr32[1] = w2;
325 	addr->s6_addr32[2] = w3;
326 	addr->s6_addr32[3] = w4;
327 }
328 #endif
329 
330 static inline int ipv6_addr_equal(const struct in6_addr *a1,
331 				  const struct in6_addr *a2)
332 {
333 	return (a1->s6_addr32[0] == a2->s6_addr32[0] &&
334 		a1->s6_addr32[1] == a2->s6_addr32[1] &&
335 		a1->s6_addr32[2] == a2->s6_addr32[2] &&
336 		a1->s6_addr32[3] == a2->s6_addr32[3]);
337 }
338 
339 static inline int __ipv6_prefix_equal(const u32 *a1, const u32 *a2,
340 				      unsigned int prefixlen)
341 {
342 	unsigned pdw, pbi;
343 
344 	/* check complete u32 in prefix */
345 	pdw = prefixlen >> 5;
346 	if (pdw && memcmp(a1, a2, pdw << 2))
347 		return 0;
348 
349 	/* check incomplete u32 in prefix */
350 	pbi = prefixlen & 0x1f;
351 	if (pbi && ((a1[pdw] ^ a2[pdw]) & htonl((0xffffffff) << (32 - pbi))))
352 		return 0;
353 
354 	return 1;
355 }
356 
357 static inline int ipv6_prefix_equal(const struct in6_addr *a1,
358 				    const struct in6_addr *a2,
359 				    unsigned int prefixlen)
360 {
361 	return __ipv6_prefix_equal(a1->s6_addr32, a2->s6_addr32,
362 				   prefixlen);
363 }
364 
365 static inline int ipv6_addr_any(const struct in6_addr *a)
366 {
367 	return ((a->s6_addr32[0] | a->s6_addr32[1] |
368 		 a->s6_addr32[2] | a->s6_addr32[3] ) == 0);
369 }
370 
371 /*
372  * find the first different bit between two addresses
373  * length of address must be a multiple of 32bits
374  */
375 static inline int __ipv6_addr_diff(const void *token1, const void *token2, int addrlen)
376 {
377 	const __u32 *a1 = token1, *a2 = token2;
378 	int i;
379 
380 	addrlen >>= 2;
381 
382 	for (i = 0; i < addrlen; i++) {
383 		__u32 xb = a1[i] ^ a2[i];
384 		if (xb) {
385 			int j = 31;
386 
387 			xb = ntohl(xb);
388 			while ((xb & (1 << j)) == 0)
389 				j--;
390 
391 			return (i * 32 + 31 - j);
392 		}
393 	}
394 
395 	/*
396 	 *	we should *never* get to this point since that
397 	 *	would mean the addrs are equal
398 	 *
399 	 *	However, we do get to it 8) And exacly, when
400 	 *	addresses are equal 8)
401 	 *
402 	 *	ip route add 1111::/128 via ...
403 	 *	ip route add 1111::/64 via ...
404 	 *	and we are here.
405 	 *
406 	 *	Ideally, this function should stop comparison
407 	 *	at prefix length. It does not, but it is still OK,
408 	 *	if returned value is greater than prefix length.
409 	 *					--ANK (980803)
410 	 */
411 	return (addrlen << 5);
412 }
413 
414 static inline int ipv6_addr_diff(const struct in6_addr *a1, const struct in6_addr *a2)
415 {
416 	return __ipv6_addr_diff(a1, a2, sizeof(struct in6_addr));
417 }
418 
419 /*
420  *	Prototypes exported by ipv6
421  */
422 
423 /*
424  *	rcv function (called from netdevice level)
425  */
426 
427 extern int			ipv6_rcv(struct sk_buff *skb,
428 					 struct net_device *dev,
429 					 struct packet_type *pt,
430 					 struct net_device *orig_dev);
431 
432 extern int			ip6_rcv_finish(struct sk_buff *skb);
433 
434 /*
435  *	upper-layer output functions
436  */
437 extern int			ip6_xmit(struct sock *sk,
438 					 struct sk_buff *skb,
439 					 struct flowi *fl,
440 					 struct ipv6_txoptions *opt,
441 					 int ipfragok);
442 
443 extern int			ip6_nd_hdr(struct sock *sk,
444 					   struct sk_buff *skb,
445 					   struct net_device *dev,
446 					   struct in6_addr *saddr,
447 					   struct in6_addr *daddr,
448 					   int proto, int len);
449 
450 extern int			ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr);
451 
452 extern int			ip6_append_data(struct sock *sk,
453 						int getfrag(void *from, char *to, int offset, int len, int odd, struct sk_buff *skb),
454 		    				void *from,
455 						int length,
456 						int transhdrlen,
457 		      				int hlimit,
458 		      				int tclass,
459 						struct ipv6_txoptions *opt,
460 						struct flowi *fl,
461 						struct rt6_info *rt,
462 						unsigned int flags);
463 
464 extern int			ip6_push_pending_frames(struct sock *sk);
465 
466 extern void			ip6_flush_pending_frames(struct sock *sk);
467 
468 extern int			ip6_dst_lookup(struct sock *sk,
469 					       struct dst_entry **dst,
470 					       struct flowi *fl);
471 
472 /*
473  *	skb processing functions
474  */
475 
476 extern int			ip6_output(struct sk_buff *skb);
477 extern int			ip6_forward(struct sk_buff *skb);
478 extern int			ip6_input(struct sk_buff *skb);
479 extern int			ip6_mc_input(struct sk_buff *skb);
480 
481 /*
482  *	Extension header (options) processing
483  */
484 
485 extern u8 *			ipv6_build_nfrag_opts(struct sk_buff *skb,
486 						      u8 *prev_hdr,
487 						      struct ipv6_txoptions *opt,
488 						      struct in6_addr *daddr,
489 						      u32 jumbolen);
490 extern u8 *			ipv6_build_frag_opts(struct sk_buff *skb,
491 						     u8 *prev_hdr,
492 						     struct ipv6_txoptions *opt);
493 extern void 			ipv6_push_nfrag_opts(struct sk_buff *skb,
494 						     struct ipv6_txoptions *opt,
495 						     u8 *proto,
496 						     struct in6_addr **daddr_p);
497 extern void			ipv6_push_frag_opts(struct sk_buff *skb,
498 						    struct ipv6_txoptions *opt,
499 						    u8 *proto);
500 
501 extern int			ipv6_skip_exthdr(const struct sk_buff *, int start,
502 					         u8 *nexthdrp);
503 
504 extern int 			ipv6_ext_hdr(u8 nexthdr);
505 
506 extern struct ipv6_txoptions *	ipv6_invert_rthdr(struct sock *sk,
507 						  struct ipv6_rt_hdr *hdr);
508 
509 
510 /*
511  *	socket options (ipv6_sockglue.c)
512  */
513 
514 extern int			ipv6_setsockopt(struct sock *sk, int level,
515 						int optname,
516 						char __user *optval,
517 						int optlen);
518 extern int			ipv6_getsockopt(struct sock *sk, int level,
519 						int optname,
520 						char __user *optval,
521 						int __user *optlen);
522 extern int			compat_ipv6_setsockopt(struct sock *sk,
523 						int level,
524 						int optname,
525 						char __user *optval,
526 						int optlen);
527 extern int			compat_ipv6_getsockopt(struct sock *sk,
528 						int level,
529 						int optname,
530 						char __user *optval,
531 						int __user *optlen);
532 
533 extern void			ipv6_packet_init(void);
534 
535 extern void			ipv6_packet_cleanup(void);
536 
537 extern int			ip6_datagram_connect(struct sock *sk,
538 						     struct sockaddr *addr, int addr_len);
539 
540 extern int 			ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len);
541 extern void			ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err, u16 port,
542 						u32 info, u8 *payload);
543 extern void			ipv6_local_error(struct sock *sk, int err, struct flowi *fl, u32 info);
544 
545 extern int inet6_release(struct socket *sock);
546 extern int inet6_bind(struct socket *sock, struct sockaddr *uaddr,
547 		      int addr_len);
548 extern int inet6_getname(struct socket *sock, struct sockaddr *uaddr,
549 			 int *uaddr_len, int peer);
550 extern int inet6_ioctl(struct socket *sock, unsigned int cmd,
551 		       unsigned long arg);
552 
553 extern int inet6_hash_connect(struct inet_timewait_death_row *death_row,
554 			      struct sock *sk);
555 
556 /*
557  * reassembly.c
558  */
559 extern int sysctl_ip6frag_high_thresh;
560 extern int sysctl_ip6frag_low_thresh;
561 extern int sysctl_ip6frag_time;
562 extern int sysctl_ip6frag_secret_interval;
563 
564 extern const struct proto_ops inet6_stream_ops;
565 extern const struct proto_ops inet6_dgram_ops;
566 
567 struct group_source_req;
568 struct group_filter;
569 
570 extern int ip6_mc_source(int add, int omode, struct sock *sk,
571 			 struct group_source_req *pgsr);
572 extern int ip6_mc_msfilter(struct sock *sk, struct group_filter *gsf);
573 extern int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf,
574 			 struct group_filter __user *optval,
575 			 int __user *optlen);
576 
577 #ifdef CONFIG_PROC_FS
578 extern int  ac6_proc_init(void);
579 extern void ac6_proc_exit(void);
580 extern int  raw6_proc_init(void);
581 extern void raw6_proc_exit(void);
582 extern int  tcp6_proc_init(void);
583 extern void tcp6_proc_exit(void);
584 extern int  udp6_proc_init(void);
585 extern void udp6_proc_exit(void);
586 extern int  ipv6_misc_proc_init(void);
587 extern void ipv6_misc_proc_exit(void);
588 
589 extern struct rt6_statistics rt6_stats;
590 #endif
591 
592 #ifdef CONFIG_SYSCTL
593 extern ctl_table ipv6_route_table[];
594 extern ctl_table ipv6_icmp_table[];
595 
596 extern void ipv6_sysctl_register(void);
597 extern void ipv6_sysctl_unregister(void);
598 #endif
599 
600 #endif /* __KERNEL__ */
601 #endif /* _NET_IPV6_H */
602