xref: /freebsd/sys/netinet/in_var.h (revision 4e99f45480598189d49d45a825533a6c9e12f02c)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1985, 1986, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  *
31  *	@(#)in_var.h	8.2 (Berkeley) 1/9/95
32  * $FreeBSD$
33  */
34 
35 #ifndef _NETINET_IN_VAR_H_
36 #define _NETINET_IN_VAR_H_
37 
38 /*
39  * Argument structure for SIOCAIFADDR.
40  */
41 struct	in_aliasreq {
42 	char	ifra_name[IFNAMSIZ];		/* if name, e.g. "en0" */
43 	struct	sockaddr_in ifra_addr;
44 	struct	sockaddr_in ifra_broadaddr;
45 #define ifra_dstaddr ifra_broadaddr
46 	struct	sockaddr_in ifra_mask;
47 	int	ifra_vhid;
48 };
49 
50 #ifdef _KERNEL
51 #include <sys/queue.h>
52 #include <sys/fnv_hash.h>
53 #include <sys/tree.h>
54 
55 struct igmp_ifsoftc;
56 struct in_multi;
57 struct lltable;
58 SLIST_HEAD(in_multi_head, in_multi);
59 
60 /*
61  * IPv4 per-interface state.
62  */
63 struct in_ifinfo {
64 	struct lltable		*ii_llt;	/* ARP state */
65 	struct igmp_ifsoftc	*ii_igmp;	/* IGMP state */
66 	struct in_multi		*ii_allhosts;	/* 224.0.0.1 membership */
67 };
68 
69 /*
70  * Interface address, Internet version.  One of these structures
71  * is allocated for each Internet address on an interface.
72  * The ifaddr structure contains the protocol-independent part
73  * of the structure and is assumed to be first.
74  */
75 struct in_ifaddr {
76 	struct	ifaddr ia_ifa;		/* protocol-independent info */
77 #define	ia_ifp		ia_ifa.ifa_ifp
78 #define ia_flags	ia_ifa.ifa_flags
79 					/* ia_subnet{,mask} in host order */
80 	u_long	ia_subnet;		/* subnet address */
81 	u_long	ia_subnetmask;		/* mask of subnet */
82 	LIST_ENTRY(in_ifaddr) ia_hash;	/* entry in bucket of inet addresses */
83 	CK_STAILQ_ENTRY(in_ifaddr) ia_link;	/* list of internet addresses */
84 	struct	sockaddr_in ia_addr;	/* reserve space for interface name */
85 	struct	sockaddr_in ia_dstaddr; /* reserve space for broadcast addr */
86 #define	ia_broadaddr	ia_dstaddr
87 	struct	sockaddr_in ia_sockmask; /* reserve space for general netmask */
88 	struct	callout ia_garp_timer;	/* timer for retransmitting GARPs */
89 	int	ia_garp_count;		/* count of retransmitted GARPs */
90 };
91 
92 /*
93  * Given a pointer to an in_ifaddr (ifaddr),
94  * return a pointer to the addr as a sockaddr_in.
95  */
96 #define IA_SIN(ia)    (&(((struct in_ifaddr *)(ia))->ia_addr))
97 #define IA_DSTSIN(ia) (&(((struct in_ifaddr *)(ia))->ia_dstaddr))
98 #define IA_MASKSIN(ia) (&(((struct in_ifaddr *)(ia))->ia_sockmask))
99 
100 #define IN_LNAOF(in, ifa) \
101 	((ntohl((in).s_addr) & ~((struct in_ifaddr *)(ifa)->ia_subnetmask))
102 
103 extern	u_char	inetctlerrmap[];
104 
105 #define LLTABLE(ifp)	\
106 	((struct in_ifinfo *)(ifp)->if_afdata[AF_INET])->ii_llt
107 /*
108  * Hash table for IP addresses.
109  */
110 CK_STAILQ_HEAD(in_ifaddrhead, in_ifaddr);
111 LIST_HEAD(in_ifaddrhashhead, in_ifaddr);
112 
113 VNET_DECLARE(struct in_ifaddrhashhead *, in_ifaddrhashtbl);
114 VNET_DECLARE(struct in_ifaddrhead, in_ifaddrhead);
115 VNET_DECLARE(u_long, in_ifaddrhmask);		/* mask for hash table */
116 
117 #define	V_in_ifaddrhashtbl	VNET(in_ifaddrhashtbl)
118 #define	V_in_ifaddrhead		VNET(in_ifaddrhead)
119 #define	V_in_ifaddrhmask	VNET(in_ifaddrhmask)
120 
121 #define INADDR_NHASH_LOG2       9
122 #define INADDR_NHASH		(1 << INADDR_NHASH_LOG2)
123 #define INADDR_HASHVAL(x)	fnv_32_buf((&(x)), sizeof(x), FNV1_32_INIT)
124 #define INADDR_HASH(x) \
125 	(&V_in_ifaddrhashtbl[INADDR_HASHVAL(x) & V_in_ifaddrhmask])
126 
127 extern	struct rmlock in_ifaddr_lock;
128 
129 #define	IN_IFADDR_LOCK_ASSERT()	rm_assert(&in_ifaddr_lock, RA_LOCKED)
130 #define	IN_IFADDR_RLOCK(t)	rm_rlock(&in_ifaddr_lock, (t))
131 #define	IN_IFADDR_RLOCK_ASSERT()	rm_assert(&in_ifaddr_lock, RA_RLOCKED)
132 #define	IN_IFADDR_RUNLOCK(t)	rm_runlock(&in_ifaddr_lock, (t))
133 #define	IN_IFADDR_WLOCK()	rm_wlock(&in_ifaddr_lock)
134 #define	IN_IFADDR_WLOCK_ASSERT()	rm_assert(&in_ifaddr_lock, RA_WLOCKED)
135 #define	IN_IFADDR_WUNLOCK()	rm_wunlock(&in_ifaddr_lock)
136 
137 /*
138  * Macro for finding the internet address structure (in_ifaddr)
139  * corresponding to one of our IP addresses (in_addr).
140  */
141 #define INADDR_TO_IFADDR(addr, ia) \
142 	/* struct in_addr addr; */ \
143 	/* struct in_ifaddr *ia; */ \
144 do { \
145 \
146 	LIST_FOREACH(ia, INADDR_HASH((addr).s_addr), ia_hash) \
147 		if (IA_SIN(ia)->sin_addr.s_addr == (addr).s_addr) \
148 			break; \
149 } while (0)
150 
151 /*
152  * Macro for finding the interface (ifnet structure) corresponding to one
153  * of our IP addresses.
154  */
155 #define INADDR_TO_IFP(addr, ifp) \
156 	/* struct in_addr addr; */ \
157 	/* struct ifnet *ifp; */ \
158 { \
159 	struct in_ifaddr *ia; \
160 \
161 	INADDR_TO_IFADDR(addr, ia); \
162 	(ifp) = (ia == NULL) ? NULL : ia->ia_ifp; \
163 }
164 
165 /*
166  * Macro for finding the internet address structure (in_ifaddr) corresponding
167  * to a given interface (ifnet structure).
168  */
169 #define IFP_TO_IA(ifp, ia, t)						\
170 	/* struct ifnet *ifp; */					\
171 	/* struct in_ifaddr *ia; */					\
172 	/* struct rm_priotracker *t; */					\
173 do {									\
174 	NET_EPOCH_ASSERT();						\
175 	IN_IFADDR_RLOCK((t));						\
176 	for ((ia) = CK_STAILQ_FIRST(&V_in_ifaddrhead);			\
177 	    (ia) != NULL && (ia)->ia_ifp != (ifp);			\
178 	    (ia) = CK_STAILQ_NEXT((ia), ia_link))				\
179 		continue;						\
180 	IN_IFADDR_RUNLOCK((t));						\
181 } while (0)
182 
183 /*
184  * Legacy IPv4 IGMP per-link structure.
185  */
186 struct router_info {
187 	struct ifnet *rti_ifp;
188 	int    rti_type; /* type of router which is querier on this interface */
189 	int    rti_time; /* # of slow timeouts since last old query */
190 	SLIST_ENTRY(router_info) rti_list;
191 };
192 
193 /*
194  * IPv4 multicast IGMP-layer source entry.
195  */
196 struct ip_msource {
197 	RB_ENTRY(ip_msource)	ims_link;	/* RB tree links */
198 	in_addr_t		ims_haddr;	/* host byte order */
199 	struct ims_st {
200 		uint16_t	ex;		/* # of exclusive members */
201 		uint16_t	in;		/* # of inclusive members */
202 	}			ims_st[2];	/* state at t0, t1 */
203 	uint8_t			ims_stp;	/* pending query */
204 };
205 
206 /*
207  * IPv4 multicast PCB-layer source entry.
208  */
209 struct in_msource {
210 	RB_ENTRY(ip_msource)	ims_link;	/* RB tree links */
211 	in_addr_t		ims_haddr;	/* host byte order */
212 	uint8_t			imsl_st[2];	/* state before/at commit */
213 };
214 
215 RB_HEAD(ip_msource_tree, ip_msource);	/* define struct ip_msource_tree */
216 
217 static __inline int
218 ip_msource_cmp(const struct ip_msource *a, const struct ip_msource *b)
219 {
220 
221 	if (a->ims_haddr < b->ims_haddr)
222 		return (-1);
223 	if (a->ims_haddr == b->ims_haddr)
224 		return (0);
225 	return (1);
226 }
227 RB_PROTOTYPE(ip_msource_tree, ip_msource, ims_link, ip_msource_cmp);
228 
229 /*
230  * IPv4 multicast PCB-layer group filter descriptor.
231  */
232 struct in_mfilter {
233 	struct ip_msource_tree	imf_sources; /* source list for (S,G) */
234 	u_long			imf_nsrc;    /* # of source entries */
235 	uint8_t			imf_st[2];   /* state before/at commit */
236 	struct in_multi	       *imf_inm;     /* associated multicast address */
237 	STAILQ_ENTRY(in_mfilter) imf_entry;  /* list entry */
238 };
239 
240 /*
241  * Helper types and functions for IPv4 multicast filters.
242  */
243 STAILQ_HEAD(ip_mfilter_head, in_mfilter);
244 
245 struct in_mfilter *ip_mfilter_alloc(int mflags, int st0, int st1);
246 void ip_mfilter_free(struct in_mfilter *);
247 
248 static inline void
249 ip_mfilter_init(struct ip_mfilter_head *head)
250 {
251 
252 	STAILQ_INIT(head);
253 }
254 
255 static inline struct in_mfilter *
256 ip_mfilter_first(const struct ip_mfilter_head *head)
257 {
258 
259 	return (STAILQ_FIRST(head));
260 }
261 
262 static inline void
263 ip_mfilter_insert(struct ip_mfilter_head *head, struct in_mfilter *imf)
264 {
265 
266 	STAILQ_INSERT_TAIL(head, imf, imf_entry);
267 }
268 
269 static inline void
270 ip_mfilter_remove(struct ip_mfilter_head *head, struct in_mfilter *imf)
271 {
272 
273 	STAILQ_REMOVE(head, imf, in_mfilter, imf_entry);
274 }
275 
276 #define	IP_MFILTER_FOREACH(imf, head) \
277 	STAILQ_FOREACH(imf, head, imf_entry)
278 
279 static inline size_t
280 ip_mfilter_count(struct ip_mfilter_head *head)
281 {
282 	struct in_mfilter *imf;
283 	size_t num = 0;
284 
285 	STAILQ_FOREACH(imf, head, imf_entry)
286 		num++;
287 	return (num);
288 }
289 
290 /*
291  * IPv4 group descriptor.
292  *
293  * For every entry on an ifnet's if_multiaddrs list which represents
294  * an IP multicast group, there is one of these structures.
295  *
296  * If any source filters are present, then a node will exist in the RB-tree
297  * to permit fast lookup by source whenever an operation takes place.
298  * This permits pre-order traversal when we issue reports.
299  * Source filter trees are kept separately from the socket layer to
300  * greatly simplify locking.
301  *
302  * When IGMPv3 is active, inm_timer is the response to group query timer.
303  * The state-change timer inm_sctimer is separate; whenever state changes
304  * for the group the state change record is generated and transmitted,
305  * and kept if retransmissions are necessary.
306  *
307  * FUTURE: inm_link is now only used when groups are being purged
308  * on a detaching ifnet. It could be demoted to a SLIST_ENTRY, but
309  * because it is at the very start of the struct, we can't do this
310  * w/o breaking the ABI for ifmcstat.
311  */
312 struct in_multi {
313 	LIST_ENTRY(in_multi) inm_link;	/* to-be-released by in_ifdetach */
314 	struct	in_addr inm_addr;	/* IP multicast address, convenience */
315 	struct	ifnet *inm_ifp;		/* back pointer to ifnet */
316 	struct	ifmultiaddr *inm_ifma;	/* back pointer to ifmultiaddr */
317 	u_int	inm_timer;		/* IGMPv1/v2 group / v3 query timer */
318 	u_int	inm_state;		/* state of the membership */
319 	void	*inm_rti;		/* unused, legacy field */
320 	u_int	inm_refcount;		/* reference count */
321 
322 	/* New fields for IGMPv3 follow. */
323 	struct igmp_ifsoftc	*inm_igi;	/* IGMP info */
324 	SLIST_ENTRY(in_multi)	 inm_nrele;	/* to-be-released by IGMP */
325 	struct ip_msource_tree	 inm_srcs;	/* tree of sources */
326 	u_long			 inm_nsrc;	/* # of tree entries */
327 
328 	struct mbufq		 inm_scq;	/* queue of pending
329 						 * state-change packets */
330 	struct timeval		 inm_lastgsrtv;	/* Time of last G-S-R query */
331 	uint16_t		 inm_sctimer;	/* state-change timer */
332 	uint16_t		 inm_scrv;	/* state-change rexmit count */
333 
334 	/*
335 	 * SSM state counters which track state at T0 (the time the last
336 	 * state-change report's RV timer went to zero) and T1
337 	 * (time of pending report, i.e. now).
338 	 * Used for computing IGMPv3 state-change reports. Several refcounts
339 	 * are maintained here to optimize for common use-cases.
340 	 */
341 	struct inm_st {
342 		uint16_t	iss_fmode;	/* IGMP filter mode */
343 		uint16_t	iss_asm;	/* # of ASM listeners */
344 		uint16_t	iss_ex;		/* # of exclusive members */
345 		uint16_t	iss_in;		/* # of inclusive members */
346 		uint16_t	iss_rec;	/* # of recorded sources */
347 	}			inm_st[2];	/* state at t0, t1 */
348 };
349 
350 /*
351  * Helper function to derive the filter mode on a source entry
352  * from its internal counters. Predicates are:
353  *  A source is only excluded if all listeners exclude it.
354  *  A source is only included if no listeners exclude it,
355  *  and at least one listener includes it.
356  * May be used by ifmcstat(8).
357  */
358 static __inline uint8_t
359 ims_get_mode(const struct in_multi *inm, const struct ip_msource *ims,
360     uint8_t t)
361 {
362 
363 	t = !!t;
364 	if (inm->inm_st[t].iss_ex > 0 &&
365 	    inm->inm_st[t].iss_ex == ims->ims_st[t].ex)
366 		return (MCAST_EXCLUDE);
367 	else if (ims->ims_st[t].in > 0 && ims->ims_st[t].ex == 0)
368 		return (MCAST_INCLUDE);
369 	return (MCAST_UNDEFINED);
370 }
371 
372 #ifdef SYSCTL_DECL
373 SYSCTL_DECL(_net_inet);
374 SYSCTL_DECL(_net_inet_ip);
375 SYSCTL_DECL(_net_inet_raw);
376 #endif
377 
378 /*
379  * Lock macros for IPv4 layer multicast address lists.  IPv4 lock goes
380  * before link layer multicast locks in the lock order.  In most cases,
381  * consumers of IN_*_MULTI() macros should acquire the locks before
382  * calling them; users of the in_{add,del}multi() functions should not.
383  */
384 extern struct mtx in_multi_list_mtx;
385 extern struct sx in_multi_sx;
386 
387 #define	IN_MULTI_LIST_LOCK()		mtx_lock(&in_multi_list_mtx)
388 #define	IN_MULTI_LIST_UNLOCK()	mtx_unlock(&in_multi_list_mtx)
389 #define	IN_MULTI_LIST_LOCK_ASSERT()	mtx_assert(&in_multi_list_mtx, MA_OWNED)
390 #define	IN_MULTI_LIST_UNLOCK_ASSERT() mtx_assert(&in_multi_list_mtx, MA_NOTOWNED)
391 
392 #define	IN_MULTI_LOCK()		sx_xlock(&in_multi_sx)
393 #define	IN_MULTI_UNLOCK()	sx_xunlock(&in_multi_sx)
394 #define	IN_MULTI_LOCK_ASSERT()	sx_assert(&in_multi_sx, SA_XLOCKED)
395 #define	IN_MULTI_UNLOCK_ASSERT() sx_assert(&in_multi_sx, SA_XUNLOCKED)
396 
397 void inm_disconnect(struct in_multi *inm);
398 extern int ifma_restart;
399 
400 /* Acquire an in_multi record. */
401 static __inline void
402 inm_acquire_locked(struct in_multi *inm)
403 {
404 
405 	IN_MULTI_LIST_LOCK_ASSERT();
406 	++inm->inm_refcount;
407 }
408 
409 static __inline void
410 inm_acquire(struct in_multi *inm)
411 {
412 	IN_MULTI_LIST_LOCK();
413 	inm_acquire_locked(inm);
414 	IN_MULTI_LIST_UNLOCK();
415 }
416 
417 static __inline void
418 inm_rele_locked(struct in_multi_head *inmh, struct in_multi *inm)
419 {
420 	MPASS(inm->inm_refcount > 0);
421 	IN_MULTI_LIST_LOCK_ASSERT();
422 
423 	if (--inm->inm_refcount == 0) {
424 		MPASS(inmh != NULL);
425 		inm_disconnect(inm);
426 		inm->inm_ifma->ifma_protospec = NULL;
427 		SLIST_INSERT_HEAD(inmh, inm, inm_nrele);
428 	}
429 }
430 
431 /*
432  * Return values for imo_multi_filter().
433  */
434 #define MCAST_PASS		0	/* Pass */
435 #define MCAST_NOTGMEMBER	1	/* This host not a member of group */
436 #define MCAST_NOTSMEMBER	2	/* This host excluded source */
437 #define MCAST_MUTED		3	/* [deprecated] */
438 
439 struct	rtentry;
440 struct	route;
441 struct	ip_moptions;
442 
443 struct in_multi *inm_lookup_locked(struct ifnet *, const struct in_addr);
444 struct in_multi *inm_lookup(struct ifnet *, const struct in_addr);
445 int	imo_multi_filter(const struct ip_moptions *, const struct ifnet *,
446 	    const struct sockaddr *, const struct sockaddr *);
447 void	inm_commit(struct in_multi *);
448 void	inm_clear_recorded(struct in_multi *);
449 void	inm_print(const struct in_multi *);
450 int	inm_record_source(struct in_multi *inm, const in_addr_t);
451 void	inm_release_deferred(struct in_multi *);
452 void	inm_release_list_deferred(struct in_multi_head *);
453 struct	in_multi *
454 in_addmulti(struct in_addr *, struct ifnet *);
455 int	in_joingroup(struct ifnet *, const struct in_addr *,
456 	    /*const*/ struct in_mfilter *, struct in_multi **);
457 int	in_joingroup_locked(struct ifnet *, const struct in_addr *,
458 	    /*const*/ struct in_mfilter *, struct in_multi **);
459 int	in_leavegroup(struct in_multi *, /*const*/ struct in_mfilter *);
460 int	in_leavegroup_locked(struct in_multi *,
461 	    /*const*/ struct in_mfilter *);
462 int	in_control(struct socket *, u_long, caddr_t, struct ifnet *,
463 	    struct thread *);
464 int	in_addprefix(struct in_ifaddr *, int);
465 int	in_scrubprefix(struct in_ifaddr *, u_int);
466 void	in_ifscrub_all(void);
467 void	ip_input(struct mbuf *);
468 void	ip_direct_input(struct mbuf *);
469 void	in_ifadown(struct ifaddr *ifa, int);
470 struct	mbuf	*ip_tryforward(struct mbuf *);
471 void	*in_domifattach(struct ifnet *);
472 void	in_domifdetach(struct ifnet *, void *);
473 
474 #endif /* _KERNEL */
475 
476 /* INET6 stuff */
477 #include <netinet6/in6_var.h>
478 
479 #endif /* _NETINET_IN_VAR_H_ */
480