xref: /freebsd/sys/netinet/in_var.h (revision 657729a89dd578d8cfc70d6616f5c65a48a8b33a)
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 	CK_LIST_ENTRY(in_ifaddr) ia_hash;	/* hash of internet 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 #define LLTABLE(ifp)	\
104 	((struct in_ifinfo *)(ifp)->if_afdata[AF_INET])->ii_llt
105 /*
106  * Hash table for IP addresses.
107  */
108 CK_STAILQ_HEAD(in_ifaddrhead, in_ifaddr);
109 CK_LIST_HEAD(in_ifaddrhashhead, in_ifaddr);
110 
111 VNET_DECLARE(struct in_ifaddrhashhead *, in_ifaddrhashtbl);
112 VNET_DECLARE(struct in_ifaddrhead, in_ifaddrhead);
113 VNET_DECLARE(u_long, in_ifaddrhmask);		/* mask for hash table */
114 
115 #define	V_in_ifaddrhashtbl	VNET(in_ifaddrhashtbl)
116 #define	V_in_ifaddrhead		VNET(in_ifaddrhead)
117 #define	V_in_ifaddrhmask	VNET(in_ifaddrhmask)
118 
119 #define INADDR_NHASH_LOG2       9
120 #define INADDR_NHASH		(1 << INADDR_NHASH_LOG2)
121 #define INADDR_HASHVAL(x)	fnv_32_buf((&(x)), sizeof(x), FNV1_32_INIT)
122 #define INADDR_HASH(x) \
123 	(&V_in_ifaddrhashtbl[INADDR_HASHVAL(x) & V_in_ifaddrhmask])
124 
125 /*
126  * Macro for finding the internet address structure (in_ifaddr)
127  * corresponding to one of our IP addresses (in_addr).
128  */
129 #define INADDR_TO_IFADDR(addr, ia) \
130 	/* struct in_addr addr; */ \
131 	/* struct in_ifaddr *ia; */ \
132 do {									\
133 	NET_EPOCH_ASSERT();						\
134 	CK_LIST_FOREACH(ia, INADDR_HASH((addr).s_addr), ia_hash)	\
135 		if (IA_SIN(ia)->sin_addr.s_addr == (addr).s_addr)	\
136 			break;						\
137 } while (0)
138 
139 /*
140  * Macro for finding the interface (ifnet structure) corresponding to one
141  * of our IP addresses.
142  */
143 #define INADDR_TO_IFP(addr, ifp) \
144 	/* struct in_addr addr; */ \
145 	/* struct ifnet *ifp; */ \
146 { \
147 	struct in_ifaddr *ia; \
148 \
149 	INADDR_TO_IFADDR(addr, ia); \
150 	(ifp) = (ia == NULL) ? NULL : ia->ia_ifp; \
151 }
152 
153 /*
154  * Macro for finding the internet address structure (in_ifaddr) corresponding
155  * to a given interface (ifnet structure).
156  */
157 #define IFP_TO_IA(ifp, ia)						\
158 	/* struct ifnet *ifp; */					\
159 	/* struct in_ifaddr *ia; */					\
160 do {									\
161 	NET_EPOCH_ASSERT();						\
162 	for ((ia) = CK_STAILQ_FIRST(&V_in_ifaddrhead);			\
163 	    (ia) != NULL && (ia)->ia_ifp != (ifp);			\
164 	    (ia) = CK_STAILQ_NEXT((ia), ia_link))			\
165 		continue;						\
166 } while (0)
167 
168 /*
169  * Legacy IPv4 IGMP per-link structure.
170  */
171 struct router_info {
172 	struct ifnet *rti_ifp;
173 	int    rti_type; /* type of router which is querier on this interface */
174 	int    rti_time; /* # of slow timeouts since last old query */
175 	SLIST_ENTRY(router_info) rti_list;
176 };
177 
178 /*
179  * IPv4 multicast IGMP-layer source entry.
180  */
181 struct ip_msource {
182 	RB_ENTRY(ip_msource)	ims_link;	/* RB tree links */
183 	in_addr_t		ims_haddr;	/* host byte order */
184 	struct ims_st {
185 		uint16_t	ex;		/* # of exclusive members */
186 		uint16_t	in;		/* # of inclusive members */
187 	}			ims_st[2];	/* state at t0, t1 */
188 	uint8_t			ims_stp;	/* pending query */
189 };
190 
191 /*
192  * IPv4 multicast PCB-layer source entry.
193  */
194 struct in_msource {
195 	RB_ENTRY(ip_msource)	ims_link;	/* RB tree links */
196 	in_addr_t		ims_haddr;	/* host byte order */
197 	uint8_t			imsl_st[2];	/* state before/at commit */
198 };
199 
200 RB_HEAD(ip_msource_tree, ip_msource);	/* define struct ip_msource_tree */
201 
202 static __inline int
203 ip_msource_cmp(const struct ip_msource *a, const struct ip_msource *b)
204 {
205 
206 	if (a->ims_haddr < b->ims_haddr)
207 		return (-1);
208 	if (a->ims_haddr == b->ims_haddr)
209 		return (0);
210 	return (1);
211 }
212 RB_PROTOTYPE(ip_msource_tree, ip_msource, ims_link, ip_msource_cmp);
213 
214 /*
215  * IPv4 multicast PCB-layer group filter descriptor.
216  */
217 struct in_mfilter {
218 	struct ip_msource_tree	imf_sources; /* source list for (S,G) */
219 	u_long			imf_nsrc;    /* # of source entries */
220 	uint8_t			imf_st[2];   /* state before/at commit */
221 	struct in_multi	       *imf_inm;     /* associated multicast address */
222 	STAILQ_ENTRY(in_mfilter) imf_entry;  /* list entry */
223 };
224 
225 /*
226  * Helper types and functions for IPv4 multicast filters.
227  */
228 STAILQ_HEAD(ip_mfilter_head, in_mfilter);
229 
230 struct in_mfilter *ip_mfilter_alloc(int mflags, int st0, int st1);
231 void ip_mfilter_free(struct in_mfilter *);
232 
233 static inline void
234 ip_mfilter_init(struct ip_mfilter_head *head)
235 {
236 
237 	STAILQ_INIT(head);
238 }
239 
240 static inline struct in_mfilter *
241 ip_mfilter_first(const struct ip_mfilter_head *head)
242 {
243 
244 	return (STAILQ_FIRST(head));
245 }
246 
247 static inline void
248 ip_mfilter_insert(struct ip_mfilter_head *head, struct in_mfilter *imf)
249 {
250 
251 	STAILQ_INSERT_TAIL(head, imf, imf_entry);
252 }
253 
254 static inline void
255 ip_mfilter_remove(struct ip_mfilter_head *head, struct in_mfilter *imf)
256 {
257 
258 	STAILQ_REMOVE(head, imf, in_mfilter, imf_entry);
259 }
260 
261 #define	IP_MFILTER_FOREACH(imf, head) \
262 	STAILQ_FOREACH(imf, head, imf_entry)
263 
264 static inline size_t
265 ip_mfilter_count(struct ip_mfilter_head *head)
266 {
267 	struct in_mfilter *imf;
268 	size_t num = 0;
269 
270 	STAILQ_FOREACH(imf, head, imf_entry)
271 		num++;
272 	return (num);
273 }
274 
275 /*
276  * IPv4 group descriptor.
277  *
278  * For every entry on an ifnet's if_multiaddrs list which represents
279  * an IP multicast group, there is one of these structures.
280  *
281  * If any source filters are present, then a node will exist in the RB-tree
282  * to permit fast lookup by source whenever an operation takes place.
283  * This permits pre-order traversal when we issue reports.
284  * Source filter trees are kept separately from the socket layer to
285  * greatly simplify locking.
286  *
287  * When IGMPv3 is active, inm_timer is the response to group query timer.
288  * The state-change timer inm_sctimer is separate; whenever state changes
289  * for the group the state change record is generated and transmitted,
290  * and kept if retransmissions are necessary.
291  *
292  * FUTURE: inm_link is now only used when groups are being purged
293  * on a detaching ifnet. It could be demoted to a SLIST_ENTRY, but
294  * because it is at the very start of the struct, we can't do this
295  * w/o breaking the ABI for ifmcstat.
296  */
297 struct in_multi {
298 	LIST_ENTRY(in_multi) inm_link;	/* to-be-released by in_ifdetach */
299 	struct	in_addr inm_addr;	/* IP multicast address, convenience */
300 	struct	ifnet *inm_ifp;		/* back pointer to ifnet */
301 	struct	ifmultiaddr *inm_ifma;	/* back pointer to ifmultiaddr */
302 	u_int	inm_timer;		/* IGMPv1/v2 group / v3 query timer */
303 	u_int	inm_state;		/* state of the membership */
304 	void	*inm_rti;		/* unused, legacy field */
305 	u_int	inm_refcount;		/* reference count */
306 
307 	/* New fields for IGMPv3 follow. */
308 	struct igmp_ifsoftc	*inm_igi;	/* IGMP info */
309 	SLIST_ENTRY(in_multi)	 inm_nrele;	/* to-be-released by IGMP */
310 	struct ip_msource_tree	 inm_srcs;	/* tree of sources */
311 	u_long			 inm_nsrc;	/* # of tree entries */
312 
313 	struct mbufq		 inm_scq;	/* queue of pending
314 						 * state-change packets */
315 	struct timeval		 inm_lastgsrtv;	/* Time of last G-S-R query */
316 	uint16_t		 inm_sctimer;	/* state-change timer */
317 	uint16_t		 inm_scrv;	/* state-change rexmit count */
318 
319 	/*
320 	 * SSM state counters which track state at T0 (the time the last
321 	 * state-change report's RV timer went to zero) and T1
322 	 * (time of pending report, i.e. now).
323 	 * Used for computing IGMPv3 state-change reports. Several refcounts
324 	 * are maintained here to optimize for common use-cases.
325 	 */
326 	struct inm_st {
327 		uint16_t	iss_fmode;	/* IGMP filter mode */
328 		uint16_t	iss_asm;	/* # of ASM listeners */
329 		uint16_t	iss_ex;		/* # of exclusive members */
330 		uint16_t	iss_in;		/* # of inclusive members */
331 		uint16_t	iss_rec;	/* # of recorded sources */
332 	}			inm_st[2];	/* state at t0, t1 */
333 };
334 
335 /*
336  * Helper function to derive the filter mode on a source entry
337  * from its internal counters. Predicates are:
338  *  A source is only excluded if all listeners exclude it.
339  *  A source is only included if no listeners exclude it,
340  *  and at least one listener includes it.
341  * May be used by ifmcstat(8).
342  */
343 static __inline uint8_t
344 ims_get_mode(const struct in_multi *inm, const struct ip_msource *ims,
345     uint8_t t)
346 {
347 
348 	t = !!t;
349 	if (inm->inm_st[t].iss_ex > 0 &&
350 	    inm->inm_st[t].iss_ex == ims->ims_st[t].ex)
351 		return (MCAST_EXCLUDE);
352 	else if (ims->ims_st[t].in > 0 && ims->ims_st[t].ex == 0)
353 		return (MCAST_INCLUDE);
354 	return (MCAST_UNDEFINED);
355 }
356 
357 #ifdef SYSCTL_DECL
358 SYSCTL_DECL(_net_inet);
359 SYSCTL_DECL(_net_inet_ip);
360 SYSCTL_DECL(_net_inet_raw);
361 #endif
362 
363 /*
364  * Lock macros for IPv4 layer multicast address lists.  IPv4 lock goes
365  * before link layer multicast locks in the lock order.  In most cases,
366  * consumers of IN_*_MULTI() macros should acquire the locks before
367  * calling them; users of the in_{add,del}multi() functions should not.
368  */
369 extern struct mtx in_multi_list_mtx;
370 extern struct sx in_multi_sx;
371 
372 #define	IN_MULTI_LIST_LOCK()		mtx_lock(&in_multi_list_mtx)
373 #define	IN_MULTI_LIST_UNLOCK()	mtx_unlock(&in_multi_list_mtx)
374 #define	IN_MULTI_LIST_LOCK_ASSERT()	mtx_assert(&in_multi_list_mtx, MA_OWNED)
375 #define	IN_MULTI_LIST_UNLOCK_ASSERT() mtx_assert(&in_multi_list_mtx, MA_NOTOWNED)
376 
377 #define	IN_MULTI_LOCK()		sx_xlock(&in_multi_sx)
378 #define	IN_MULTI_UNLOCK()	sx_xunlock(&in_multi_sx)
379 #define	IN_MULTI_LOCK_ASSERT()	sx_assert(&in_multi_sx, SA_XLOCKED)
380 #define	IN_MULTI_UNLOCK_ASSERT() sx_assert(&in_multi_sx, SA_XUNLOCKED)
381 
382 void inm_disconnect(struct in_multi *inm);
383 
384 /*
385  * Get the in_multi pointer from a ifmultiaddr.
386  * Returns NULL if ifmultiaddr is no longer valid.
387  */
388 static __inline struct in_multi *
389 inm_ifmultiaddr_get_inm(struct ifmultiaddr *ifma)
390 {
391 
392 	NET_EPOCH_ASSERT();
393 
394 	return ((ifma->ifma_addr->sa_family != AF_INET ||
395 	    (ifma->ifma_flags & IFMA_F_ENQUEUED) == 0) ? NULL :
396 	    ifma->ifma_protospec);
397 }
398 
399 /* Acquire an in_multi record. */
400 static __inline void
401 inm_acquire_locked(struct in_multi *inm)
402 {
403 
404 	IN_MULTI_LIST_LOCK_ASSERT();
405 	++inm->inm_refcount;
406 }
407 
408 static __inline void
409 inm_acquire(struct in_multi *inm)
410 {
411 	IN_MULTI_LIST_LOCK();
412 	inm_acquire_locked(inm);
413 	IN_MULTI_LIST_UNLOCK();
414 }
415 
416 static __inline void
417 inm_rele_locked(struct in_multi_head *inmh, struct in_multi *inm)
418 {
419 	MPASS(inm->inm_refcount > 0);
420 	IN_MULTI_LIST_LOCK_ASSERT();
421 
422 	if (--inm->inm_refcount == 0) {
423 		MPASS(inmh != NULL);
424 		inm_disconnect(inm);
425 		inm->inm_ifma->ifma_protospec = NULL;
426 		SLIST_INSERT_HEAD(inmh, inm, inm_nrele);
427 	}
428 }
429 
430 /*
431  * Return values for imo_multi_filter().
432  */
433 #define MCAST_PASS		0	/* Pass */
434 #define MCAST_NOTGMEMBER	1	/* This host not a member of group */
435 #define MCAST_NOTSMEMBER	2	/* This host excluded source */
436 #define MCAST_MUTED		3	/* [deprecated] */
437 
438 struct rib_head;
439 struct	ip_moptions;
440 
441 struct in_multi *inm_lookup_locked(struct ifnet *, const struct in_addr);
442 struct in_multi *inm_lookup(struct ifnet *, const struct in_addr);
443 int	imo_multi_filter(const struct ip_moptions *, const struct ifnet *,
444 	    const struct sockaddr *, const struct sockaddr *);
445 void	inm_commit(struct in_multi *);
446 void	inm_clear_recorded(struct in_multi *);
447 void	inm_print(const struct in_multi *);
448 int	inm_record_source(struct in_multi *inm, const in_addr_t);
449 void	inm_release_deferred(struct in_multi *);
450 void	inm_release_list_deferred(struct in_multi_head *);
451 void	inm_release_wait(void *);
452 int	in_joingroup(struct ifnet *, const struct in_addr *,
453 	    /*const*/ struct in_mfilter *, struct in_multi **);
454 int	in_joingroup_locked(struct ifnet *, const struct in_addr *,
455 	    /*const*/ struct in_mfilter *, struct in_multi **);
456 int	in_leavegroup(struct in_multi *, /*const*/ struct in_mfilter *);
457 int	in_leavegroup_locked(struct in_multi *,
458 	    /*const*/ struct in_mfilter *);
459 int	in_control(struct socket *, u_long, void *, struct ifnet *,
460 	    struct thread *);
461 int	in_addprefix(struct in_ifaddr *);
462 int	in_scrubprefix(struct in_ifaddr *, u_int);
463 void	in_ifscrub_all(void);
464 void	ip_input(struct mbuf *);
465 void	ip_direct_input(struct mbuf *);
466 void	in_ifadown(struct ifaddr *ifa, int);
467 struct	mbuf	*ip_tryforward(struct mbuf *);
468 void	*in_domifattach(struct ifnet *);
469 void	in_domifdetach(struct ifnet *, void *);
470 struct rib_head *in_inithead(uint32_t fibnum);
471 #ifdef VIMAGE
472 void	in_detachhead(struct rib_head *rh);
473 #endif
474 
475 #endif /* _KERNEL */
476 
477 /* INET6 stuff */
478 #include <netinet6/in6_var.h>
479 
480 #endif /* _NETINET_IN_VAR_H_ */
481