xref: /freebsd/sys/netinet/in_var.h (revision d0b2dbfa0ecf2bbc9709efc5e20baf8e4b44bbbf)
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  */
33 
34 #ifndef _NETINET_IN_VAR_H_
35 #define _NETINET_IN_VAR_H_
36 
37 /*
38  * Argument structure for SIOCAIFADDR.
39  */
40 struct	in_aliasreq {
41 	char	ifra_name[IFNAMSIZ];		/* if name, e.g. "en0" */
42 	struct	sockaddr_in ifra_addr;
43 	struct	sockaddr_in ifra_broadaddr;
44 #define ifra_dstaddr ifra_broadaddr
45 	struct	sockaddr_in ifra_mask;
46 	int	ifra_vhid;
47 };
48 
49 #ifdef _KERNEL
50 #include <sys/queue.h>
51 #include <sys/fnv_hash.h>
52 #include <sys/tree.h>
53 
54 struct igmp_ifsoftc;
55 struct in_multi;
56 struct lltable;
57 SLIST_HEAD(in_multi_head, in_multi);
58 
59 /*
60  * IPv4 per-interface state.
61  */
62 struct in_ifinfo {
63 	struct lltable		*ii_llt;	/* ARP state */
64 	struct igmp_ifsoftc	*ii_igmp;	/* IGMP state */
65 	struct in_multi		*ii_allhosts;	/* 224.0.0.1 membership */
66 };
67 
68 /*
69  * Interface address, Internet version.  One of these structures
70  * is allocated for each Internet address on an interface.
71  * The ifaddr structure contains the protocol-independent part
72  * of the structure and is assumed to be first.
73  */
74 struct in_ifaddr {
75 	struct	ifaddr ia_ifa;		/* protocol-independent info */
76 #define	ia_ifp		ia_ifa.ifa_ifp
77 #define ia_flags	ia_ifa.ifa_flags
78 					/* ia_subnet{,mask} in host order */
79 	u_long	ia_subnet;		/* subnet address */
80 	u_long	ia_subnetmask;		/* mask of subnet */
81 	CK_LIST_ENTRY(in_ifaddr) ia_hash;	/* hash of internet addresses */
82 	CK_STAILQ_ENTRY(in_ifaddr) ia_link;	/* list of internet addresses */
83 	struct	sockaddr_in ia_addr;	/* reserve space for interface name */
84 	struct	sockaddr_in ia_dstaddr; /* reserve space for broadcast addr */
85 #define	ia_broadaddr	ia_dstaddr
86 	struct	sockaddr_in ia_sockmask; /* reserve space for general netmask */
87 	struct	callout ia_garp_timer;	/* timer for retransmitting GARPs */
88 	int	ia_garp_count;		/* count of retransmitted GARPs */
89 };
90 
91 /*
92  * Given a pointer to an in_ifaddr (ifaddr),
93  * return a pointer to the addr as a sockaddr_in.
94  */
95 #define IA_SIN(ia)    (&(((struct in_ifaddr *)(ia))->ia_addr))
96 #define IA_DSTSIN(ia) (&(((struct in_ifaddr *)(ia))->ia_dstaddr))
97 #define IA_MASKSIN(ia) (&(((struct in_ifaddr *)(ia))->ia_sockmask))
98 
99 #define IN_LNAOF(in, ifa) \
100 	((ntohl((in).s_addr) & ~((struct in_ifaddr *)(ifa)->ia_subnetmask))
101 
102 #define LLTABLE(ifp)	\
103 	((struct in_ifinfo *)(ifp)->if_afdata[AF_INET])->ii_llt
104 /*
105  * Hash table for IP addresses.
106  */
107 CK_STAILQ_HEAD(in_ifaddrhead, in_ifaddr);
108 CK_LIST_HEAD(in_ifaddrhashhead, in_ifaddr);
109 
110 VNET_DECLARE(struct in_ifaddrhashhead *, in_ifaddrhashtbl);
111 VNET_DECLARE(struct in_ifaddrhead, in_ifaddrhead);
112 VNET_DECLARE(u_long, in_ifaddrhmask);		/* mask for hash table */
113 
114 #define	V_in_ifaddrhashtbl	VNET(in_ifaddrhashtbl)
115 #define	V_in_ifaddrhead		VNET(in_ifaddrhead)
116 #define	V_in_ifaddrhmask	VNET(in_ifaddrhmask)
117 
118 #define INADDR_NHASH_LOG2       9
119 #define INADDR_NHASH		(1 << INADDR_NHASH_LOG2)
120 #define INADDR_HASHVAL(x)	fnv_32_buf((&(x)), sizeof(x), FNV1_32_INIT)
121 #define INADDR_HASH(x) \
122 	(&V_in_ifaddrhashtbl[INADDR_HASHVAL(x) & V_in_ifaddrhmask])
123 
124 /*
125  * Macro for finding the internet address structure (in_ifaddr)
126  * corresponding to one of our IP addresses (in_addr).
127  */
128 #define INADDR_TO_IFADDR(addr, ia) \
129 	/* struct in_addr addr; */ \
130 	/* struct in_ifaddr *ia; */ \
131 do {									\
132 	NET_EPOCH_ASSERT();						\
133 	CK_LIST_FOREACH(ia, INADDR_HASH((addr).s_addr), ia_hash)	\
134 		if (IA_SIN(ia)->sin_addr.s_addr == (addr).s_addr)	\
135 			break;						\
136 } while (0)
137 
138 /*
139  * Macro for finding the interface (ifnet structure) corresponding to one
140  * of our IP addresses.
141  */
142 #define INADDR_TO_IFP(addr, ifp) \
143 	/* struct in_addr addr; */ \
144 	/* struct ifnet *ifp; */ \
145 { \
146 	struct in_ifaddr *ia; \
147 \
148 	INADDR_TO_IFADDR(addr, ia); \
149 	(ifp) = (ia == NULL) ? NULL : ia->ia_ifp; \
150 }
151 
152 /*
153  * Macro for finding the internet address structure (in_ifaddr) corresponding
154  * to a given interface (ifnet structure).
155  */
156 #define IFP_TO_IA(ifp, ia)						\
157 	/* struct ifnet *ifp; */					\
158 	/* struct in_ifaddr *ia; */					\
159 do {									\
160 	NET_EPOCH_ASSERT();						\
161 	for ((ia) = CK_STAILQ_FIRST(&V_in_ifaddrhead);			\
162 	    (ia) != NULL && (ia)->ia_ifp != (ifp);			\
163 	    (ia) = CK_STAILQ_NEXT((ia), ia_link))			\
164 		continue;						\
165 } while (0)
166 
167 /*
168  * Legacy IPv4 IGMP per-link structure.
169  */
170 struct router_info {
171 	struct ifnet *rti_ifp;
172 	int    rti_type; /* type of router which is querier on this interface */
173 	int    rti_time; /* # of slow timeouts since last old query */
174 	SLIST_ENTRY(router_info) rti_list;
175 };
176 
177 /*
178  * IPv4 multicast IGMP-layer source entry.
179  */
180 struct ip_msource {
181 	RB_ENTRY(ip_msource)	ims_link;	/* RB tree links */
182 	in_addr_t		ims_haddr;	/* host byte order */
183 	struct ims_st {
184 		uint16_t	ex;		/* # of exclusive members */
185 		uint16_t	in;		/* # of inclusive members */
186 	}			ims_st[2];	/* state at t0, t1 */
187 	uint8_t			ims_stp;	/* pending query */
188 };
189 
190 /*
191  * IPv4 multicast PCB-layer source entry.
192  */
193 struct in_msource {
194 	RB_ENTRY(ip_msource)	ims_link;	/* RB tree links */
195 	in_addr_t		ims_haddr;	/* host byte order */
196 	uint8_t			imsl_st[2];	/* state before/at commit */
197 };
198 
199 RB_HEAD(ip_msource_tree, ip_msource);	/* define struct ip_msource_tree */
200 
201 static __inline int
202 ip_msource_cmp(const struct ip_msource *a, const struct ip_msource *b)
203 {
204 
205 	if (a->ims_haddr < b->ims_haddr)
206 		return (-1);
207 	if (a->ims_haddr == b->ims_haddr)
208 		return (0);
209 	return (1);
210 }
211 RB_PROTOTYPE(ip_msource_tree, ip_msource, ims_link, ip_msource_cmp);
212 
213 /*
214  * IPv4 multicast PCB-layer group filter descriptor.
215  */
216 struct in_mfilter {
217 	struct ip_msource_tree	imf_sources; /* source list for (S,G) */
218 	u_long			imf_nsrc;    /* # of source entries */
219 	uint8_t			imf_st[2];   /* state before/at commit */
220 	struct in_multi	       *imf_inm;     /* associated multicast address */
221 	STAILQ_ENTRY(in_mfilter) imf_entry;  /* list entry */
222 };
223 
224 /*
225  * Helper types and functions for IPv4 multicast filters.
226  */
227 STAILQ_HEAD(ip_mfilter_head, in_mfilter);
228 
229 struct in_mfilter *ip_mfilter_alloc(int mflags, int st0, int st1);
230 void ip_mfilter_free(struct in_mfilter *);
231 
232 static inline void
233 ip_mfilter_init(struct ip_mfilter_head *head)
234 {
235 
236 	STAILQ_INIT(head);
237 }
238 
239 static inline struct in_mfilter *
240 ip_mfilter_first(const struct ip_mfilter_head *head)
241 {
242 
243 	return (STAILQ_FIRST(head));
244 }
245 
246 static inline void
247 ip_mfilter_insert(struct ip_mfilter_head *head, struct in_mfilter *imf)
248 {
249 
250 	STAILQ_INSERT_TAIL(head, imf, imf_entry);
251 }
252 
253 static inline void
254 ip_mfilter_remove(struct ip_mfilter_head *head, struct in_mfilter *imf)
255 {
256 
257 	STAILQ_REMOVE(head, imf, in_mfilter, imf_entry);
258 }
259 
260 #define	IP_MFILTER_FOREACH(imf, head) \
261 	STAILQ_FOREACH(imf, head, imf_entry)
262 
263 static inline size_t
264 ip_mfilter_count(struct ip_mfilter_head *head)
265 {
266 	struct in_mfilter *imf;
267 	size_t num = 0;
268 
269 	STAILQ_FOREACH(imf, head, imf_entry)
270 		num++;
271 	return (num);
272 }
273 
274 /*
275  * IPv4 group descriptor.
276  *
277  * For every entry on an ifnet's if_multiaddrs list which represents
278  * an IP multicast group, there is one of these structures.
279  *
280  * If any source filters are present, then a node will exist in the RB-tree
281  * to permit fast lookup by source whenever an operation takes place.
282  * This permits pre-order traversal when we issue reports.
283  * Source filter trees are kept separately from the socket layer to
284  * greatly simplify locking.
285  *
286  * When IGMPv3 is active, inm_timer is the response to group query timer.
287  * The state-change timer inm_sctimer is separate; whenever state changes
288  * for the group the state change record is generated and transmitted,
289  * and kept if retransmissions are necessary.
290  *
291  * FUTURE: inm_link is now only used when groups are being purged
292  * on a detaching ifnet. It could be demoted to a SLIST_ENTRY, but
293  * because it is at the very start of the struct, we can't do this
294  * w/o breaking the ABI for ifmcstat.
295  */
296 struct in_multi {
297 	LIST_ENTRY(in_multi) inm_link;	/* to-be-released by in_ifdetach */
298 	struct	in_addr inm_addr;	/* IP multicast address, convenience */
299 	struct	ifnet *inm_ifp;		/* back pointer to ifnet */
300 	struct	ifmultiaddr *inm_ifma;	/* back pointer to ifmultiaddr */
301 	u_int	inm_timer;		/* IGMPv1/v2 group / v3 query timer */
302 	u_int	inm_state;		/* state of the membership */
303 	void	*inm_rti;		/* unused, legacy field */
304 	u_int	inm_refcount;		/* reference count */
305 
306 	/* New fields for IGMPv3 follow. */
307 	struct igmp_ifsoftc	*inm_igi;	/* IGMP info */
308 	SLIST_ENTRY(in_multi)	 inm_nrele;	/* to-be-released by IGMP */
309 	struct ip_msource_tree	 inm_srcs;	/* tree of sources */
310 	u_long			 inm_nsrc;	/* # of tree entries */
311 
312 	struct mbufq		 inm_scq;	/* queue of pending
313 						 * state-change packets */
314 	struct timeval		 inm_lastgsrtv;	/* Time of last G-S-R query */
315 	uint16_t		 inm_sctimer;	/* state-change timer */
316 	uint16_t		 inm_scrv;	/* state-change rexmit count */
317 
318 	/*
319 	 * SSM state counters which track state at T0 (the time the last
320 	 * state-change report's RV timer went to zero) and T1
321 	 * (time of pending report, i.e. now).
322 	 * Used for computing IGMPv3 state-change reports. Several refcounts
323 	 * are maintained here to optimize for common use-cases.
324 	 */
325 	struct inm_st {
326 		uint16_t	iss_fmode;	/* IGMP filter mode */
327 		uint16_t	iss_asm;	/* # of ASM listeners */
328 		uint16_t	iss_ex;		/* # of exclusive members */
329 		uint16_t	iss_in;		/* # of inclusive members */
330 		uint16_t	iss_rec;	/* # of recorded sources */
331 	}			inm_st[2];	/* state at t0, t1 */
332 };
333 
334 /*
335  * Helper function to derive the filter mode on a source entry
336  * from its internal counters. Predicates are:
337  *  A source is only excluded if all listeners exclude it.
338  *  A source is only included if no listeners exclude it,
339  *  and at least one listener includes it.
340  * May be used by ifmcstat(8).
341  */
342 static __inline uint8_t
343 ims_get_mode(const struct in_multi *inm, const struct ip_msource *ims,
344     uint8_t t)
345 {
346 
347 	t = !!t;
348 	if (inm->inm_st[t].iss_ex > 0 &&
349 	    inm->inm_st[t].iss_ex == ims->ims_st[t].ex)
350 		return (MCAST_EXCLUDE);
351 	else if (ims->ims_st[t].in > 0 && ims->ims_st[t].ex == 0)
352 		return (MCAST_INCLUDE);
353 	return (MCAST_UNDEFINED);
354 }
355 
356 #ifdef SYSCTL_DECL
357 SYSCTL_DECL(_net_inet);
358 SYSCTL_DECL(_net_inet_ip);
359 SYSCTL_DECL(_net_inet_raw);
360 #endif
361 
362 /*
363  * Lock macros for IPv4 layer multicast address lists.  IPv4 lock goes
364  * before link layer multicast locks in the lock order.  In most cases,
365  * consumers of IN_*_MULTI() macros should acquire the locks before
366  * calling them; users of the in_{add,del}multi() functions should not.
367  */
368 extern struct mtx in_multi_list_mtx;
369 extern struct sx in_multi_sx;
370 
371 #define	IN_MULTI_LIST_LOCK()		mtx_lock(&in_multi_list_mtx)
372 #define	IN_MULTI_LIST_UNLOCK()	mtx_unlock(&in_multi_list_mtx)
373 #define	IN_MULTI_LIST_LOCK_ASSERT()	mtx_assert(&in_multi_list_mtx, MA_OWNED)
374 #define	IN_MULTI_LIST_UNLOCK_ASSERT() mtx_assert(&in_multi_list_mtx, MA_NOTOWNED)
375 
376 #define	IN_MULTI_LOCK()		sx_xlock(&in_multi_sx)
377 #define	IN_MULTI_UNLOCK()	sx_xunlock(&in_multi_sx)
378 #define	IN_MULTI_LOCK_ASSERT()	sx_assert(&in_multi_sx, SA_XLOCKED)
379 #define	IN_MULTI_UNLOCK_ASSERT() sx_assert(&in_multi_sx, SA_XUNLOCKED)
380 
381 void inm_disconnect(struct in_multi *inm);
382 
383 /*
384  * Get the in_multi pointer from a ifmultiaddr.
385  * Returns NULL if ifmultiaddr is no longer valid.
386  */
387 static __inline struct in_multi *
388 inm_ifmultiaddr_get_inm(struct ifmultiaddr *ifma)
389 {
390 
391 	NET_EPOCH_ASSERT();
392 
393 	return ((ifma->ifma_addr->sa_family != AF_INET ||
394 	    (ifma->ifma_flags & IFMA_F_ENQUEUED) == 0) ? NULL :
395 	    ifma->ifma_protospec);
396 }
397 
398 /* Acquire an in_multi record. */
399 static __inline void
400 inm_acquire_locked(struct in_multi *inm)
401 {
402 
403 	IN_MULTI_LIST_LOCK_ASSERT();
404 	++inm->inm_refcount;
405 }
406 
407 static __inline void
408 inm_acquire(struct in_multi *inm)
409 {
410 	IN_MULTI_LIST_LOCK();
411 	inm_acquire_locked(inm);
412 	IN_MULTI_LIST_UNLOCK();
413 }
414 
415 static __inline void
416 inm_rele_locked(struct in_multi_head *inmh, struct in_multi *inm)
417 {
418 	MPASS(inm->inm_refcount > 0);
419 	IN_MULTI_LIST_LOCK_ASSERT();
420 
421 	if (--inm->inm_refcount == 0) {
422 		MPASS(inmh != NULL);
423 		inm_disconnect(inm);
424 		inm->inm_ifma->ifma_protospec = NULL;
425 		SLIST_INSERT_HEAD(inmh, inm, inm_nrele);
426 	}
427 }
428 
429 /*
430  * Return values for imo_multi_filter().
431  */
432 #define MCAST_PASS		0	/* Pass */
433 #define MCAST_NOTGMEMBER	1	/* This host not a member of group */
434 #define MCAST_NOTSMEMBER	2	/* This host excluded source */
435 #define MCAST_MUTED		3	/* [deprecated] */
436 
437 struct rib_head;
438 struct	ip_moptions;
439 struct ucred;
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_control_ioctl(u_long, void *, struct ifnet *,
462 	    struct ucred *);
463 int	in_addprefix(struct in_ifaddr *);
464 int	in_scrubprefix(struct in_ifaddr *, u_int);
465 void	in_ifscrub_all(void);
466 void	ip_input(struct mbuf *);
467 void	ip_direct_input(struct mbuf *);
468 void	in_ifadown(struct ifaddr *ifa, int);
469 struct	mbuf	*ip_tryforward(struct mbuf *);
470 void	*in_domifattach(struct ifnet *);
471 void	in_domifdetach(struct ifnet *, void *);
472 struct rib_head *in_inithead(uint32_t fibnum);
473 #ifdef VIMAGE
474 void	in_detachhead(struct rib_head *rh);
475 #endif
476 
477 #endif /* _KERNEL */
478 
479 /* INET6 stuff */
480 #include <netinet6/in6_var.h>
481 
482 #endif /* _NETINET_IN_VAR_H_ */
483