xref: /freebsd/sys/netinet/in_var.h (revision 4b9d605768acabc460aa6dcfe8a1f8db35b16794)
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 
32 #ifndef _NETINET_IN_VAR_H_
33 #define _NETINET_IN_VAR_H_
34 
35 /*
36  * Argument structure for SIOCAIFADDR.
37  */
38 struct	in_aliasreq {
39 	char	ifra_name[IFNAMSIZ];		/* if name, e.g. "en0" */
40 	struct	sockaddr_in ifra_addr;
41 	struct	sockaddr_in ifra_broadaddr;
42 #define ifra_dstaddr ifra_broadaddr
43 	struct	sockaddr_in ifra_mask;
44 	int	ifra_vhid;
45 };
46 
47 #ifdef _KERNEL
48 #include <sys/queue.h>
49 #include <sys/fnv_hash.h>
50 #include <sys/tree.h>
51 
52 struct igmp_ifsoftc;
53 struct in_multi;
54 struct lltable;
55 SLIST_HEAD(in_multi_head, in_multi);
56 
57 /*
58  * IPv4 per-interface state.
59  */
60 struct in_ifinfo {
61 	struct lltable		*ii_llt;	/* ARP state */
62 	struct igmp_ifsoftc	*ii_igmp;	/* IGMP state */
63 	struct in_multi		*ii_allhosts;	/* 224.0.0.1 membership */
64 };
65 
66 /*
67  * Interface address, Internet version.  One of these structures
68  * is allocated for each Internet address on an interface.
69  * The ifaddr structure contains the protocol-independent part
70  * of the structure and is assumed to be first.
71  */
72 struct in_ifaddr {
73 	struct	ifaddr ia_ifa;		/* protocol-independent info */
74 #define	ia_ifp		ia_ifa.ifa_ifp
75 #define ia_flags	ia_ifa.ifa_flags
76 					/* ia_subnet{,mask} in host order */
77 	u_long	ia_subnet;		/* subnet address */
78 	u_long	ia_subnetmask;		/* mask of subnet */
79 	CK_LIST_ENTRY(in_ifaddr) ia_hash;	/* hash of internet addresses */
80 	CK_STAILQ_ENTRY(in_ifaddr) ia_link;	/* list of internet addresses */
81 	struct	sockaddr_in ia_addr;	/* reserve space for interface name */
82 	struct	sockaddr_in ia_dstaddr; /* reserve space for broadcast addr */
83 #define	ia_broadaddr	ia_dstaddr
84 	struct	sockaddr_in ia_sockmask; /* reserve space for general netmask */
85 	struct	callout ia_garp_timer;	/* timer for retransmitting GARPs */
86 	int	ia_garp_count;		/* count of retransmitted GARPs */
87 };
88 
89 /*
90  * Given a pointer to an in_ifaddr (ifaddr),
91  * return a pointer to the addr as a sockaddr_in.
92  */
93 #define IA_SIN(ia)    (&(((struct in_ifaddr *)(ia))->ia_addr))
94 #define IA_DSTSIN(ia) (&(((struct in_ifaddr *)(ia))->ia_dstaddr))
95 #define IA_MASKSIN(ia) (&(((struct in_ifaddr *)(ia))->ia_sockmask))
96 
97 #define IN_LNAOF(in, ifa) \
98 	((ntohl((in).s_addr) & ~((struct in_ifaddr *)(ifa)->ia_subnetmask))
99 
100 #define LLTABLE(ifp)	\
101 	((struct in_ifinfo *)(ifp)->if_afdata[AF_INET])->ii_llt
102 /*
103  * Hash table for IP addresses.
104  */
105 CK_STAILQ_HEAD(in_ifaddrhead, in_ifaddr);
106 CK_LIST_HEAD(in_ifaddrhashhead, in_ifaddr);
107 
108 VNET_DECLARE(struct in_ifaddrhashhead *, in_ifaddrhashtbl);
109 VNET_DECLARE(struct in_ifaddrhead, in_ifaddrhead);
110 VNET_DECLARE(u_long, in_ifaddrhmask);		/* mask for hash table */
111 
112 #define	V_in_ifaddrhashtbl	VNET(in_ifaddrhashtbl)
113 #define	V_in_ifaddrhead		VNET(in_ifaddrhead)
114 #define	V_in_ifaddrhmask	VNET(in_ifaddrhmask)
115 
116 #define INADDR_NHASH_LOG2       9
117 #define INADDR_NHASH		(1 << INADDR_NHASH_LOG2)
118 #define INADDR_HASHVAL(x)	fnv_32_buf((&(x)), sizeof(x), FNV1_32_INIT)
119 #define INADDR_HASH(x) \
120 	(&V_in_ifaddrhashtbl[INADDR_HASHVAL(x) & V_in_ifaddrhmask])
121 
122 /*
123  * Macro for finding the internet address structure (in_ifaddr)
124  * corresponding to one of our IP addresses (in_addr).
125  */
126 #define INADDR_TO_IFADDR(addr, ia) \
127 	/* struct in_addr addr; */ \
128 	/* struct in_ifaddr *ia; */ \
129 do {									\
130 	NET_EPOCH_ASSERT();						\
131 	CK_LIST_FOREACH(ia, INADDR_HASH((addr).s_addr), ia_hash)	\
132 		if (IA_SIN(ia)->sin_addr.s_addr == (addr).s_addr)	\
133 			break;						\
134 } while (0)
135 
136 /*
137  * Macro for finding the interface (ifnet structure) corresponding to one
138  * of our IP addresses.
139  */
140 #define INADDR_TO_IFP(addr, ifp) \
141 	/* struct in_addr addr; */ \
142 	/* struct ifnet *ifp; */ \
143 { \
144 	struct in_ifaddr *ia; \
145 \
146 	INADDR_TO_IFADDR(addr, ia); \
147 	(ifp) = (ia == NULL) ? NULL : ia->ia_ifp; \
148 }
149 
150 /*
151  * Macro for finding the internet address structure (in_ifaddr) corresponding
152  * to a given interface (ifnet structure).
153  */
154 #define IFP_TO_IA(ifp, ia)						\
155 	/* struct ifnet *ifp; */					\
156 	/* struct in_ifaddr *ia; */					\
157 do {									\
158 	NET_EPOCH_ASSERT();						\
159 	for ((ia) = CK_STAILQ_FIRST(&V_in_ifaddrhead);			\
160 	    (ia) != NULL && (ia)->ia_ifp != (ifp);			\
161 	    (ia) = CK_STAILQ_NEXT((ia), ia_link))			\
162 		continue;						\
163 } while (0)
164 
165 /*
166  * Legacy IPv4 IGMP per-link structure.
167  */
168 struct router_info {
169 	struct ifnet *rti_ifp;
170 	int    rti_type; /* type of router which is querier on this interface */
171 	int    rti_time; /* # of slow timeouts since last old query */
172 	SLIST_ENTRY(router_info) rti_list;
173 };
174 
175 /*
176  * IPv4 multicast IGMP-layer source entry.
177  */
178 struct ip_msource {
179 	RB_ENTRY(ip_msource)	ims_link;	/* RB tree links */
180 	in_addr_t		ims_haddr;	/* host byte order */
181 	struct ims_st {
182 		uint16_t	ex;		/* # of exclusive members */
183 		uint16_t	in;		/* # of inclusive members */
184 	}			ims_st[2];	/* state at t0, t1 */
185 	uint8_t			ims_stp;	/* pending query */
186 };
187 
188 /*
189  * IPv4 multicast PCB-layer source entry.
190  */
191 struct in_msource {
192 	RB_ENTRY(ip_msource)	ims_link;	/* RB tree links */
193 	in_addr_t		ims_haddr;	/* host byte order */
194 	uint8_t			imsl_st[2];	/* state before/at commit */
195 };
196 
197 RB_HEAD(ip_msource_tree, ip_msource);	/* define struct ip_msource_tree */
198 
199 static __inline int
200 ip_msource_cmp(const struct ip_msource *a, const struct ip_msource *b)
201 {
202 
203 	if (a->ims_haddr < b->ims_haddr)
204 		return (-1);
205 	if (a->ims_haddr == b->ims_haddr)
206 		return (0);
207 	return (1);
208 }
209 RB_PROTOTYPE(ip_msource_tree, ip_msource, ims_link, ip_msource_cmp);
210 
211 /*
212  * IPv4 multicast PCB-layer group filter descriptor.
213  */
214 struct in_mfilter {
215 	struct ip_msource_tree	imf_sources; /* source list for (S,G) */
216 	u_long			imf_nsrc;    /* # of source entries */
217 	uint8_t			imf_st[2];   /* state before/at commit */
218 	struct in_multi	       *imf_inm;     /* associated multicast address */
219 	STAILQ_ENTRY(in_mfilter) imf_entry;  /* list entry */
220 };
221 
222 /*
223  * Helper types and functions for IPv4 multicast filters.
224  */
225 STAILQ_HEAD(ip_mfilter_head, in_mfilter);
226 
227 struct in_mfilter *ip_mfilter_alloc(int mflags, int st0, int st1);
228 void ip_mfilter_free(struct in_mfilter *);
229 
230 static inline void
231 ip_mfilter_init(struct ip_mfilter_head *head)
232 {
233 
234 	STAILQ_INIT(head);
235 }
236 
237 static inline struct in_mfilter *
238 ip_mfilter_first(const struct ip_mfilter_head *head)
239 {
240 
241 	return (STAILQ_FIRST(head));
242 }
243 
244 static inline void
245 ip_mfilter_insert(struct ip_mfilter_head *head, struct in_mfilter *imf)
246 {
247 
248 	STAILQ_INSERT_TAIL(head, imf, imf_entry);
249 }
250 
251 static inline void
252 ip_mfilter_remove(struct ip_mfilter_head *head, struct in_mfilter *imf)
253 {
254 
255 	STAILQ_REMOVE(head, imf, in_mfilter, imf_entry);
256 }
257 
258 #define	IP_MFILTER_FOREACH(imf, head) \
259 	STAILQ_FOREACH(imf, head, imf_entry)
260 
261 static inline size_t
262 ip_mfilter_count(struct ip_mfilter_head *head)
263 {
264 	struct in_mfilter *imf;
265 	size_t num = 0;
266 
267 	STAILQ_FOREACH(imf, head, imf_entry)
268 		num++;
269 	return (num);
270 }
271 
272 /*
273  * IPv4 group descriptor.
274  *
275  * For every entry on an ifnet's if_multiaddrs list which represents
276  * an IP multicast group, there is one of these structures.
277  *
278  * If any source filters are present, then a node will exist in the RB-tree
279  * to permit fast lookup by source whenever an operation takes place.
280  * This permits pre-order traversal when we issue reports.
281  * Source filter trees are kept separately from the socket layer to
282  * greatly simplify locking.
283  *
284  * When IGMPv3 is active, inm_timer is the response to group query timer.
285  * The state-change timer inm_sctimer is separate; whenever state changes
286  * for the group the state change record is generated and transmitted,
287  * and kept if retransmissions are necessary.
288  *
289  * FUTURE: inm_link is now only used when groups are being purged
290  * on a detaching ifnet. It could be demoted to a SLIST_ENTRY, but
291  * because it is at the very start of the struct, we can't do this
292  * w/o breaking the ABI for ifmcstat.
293  */
294 struct in_multi {
295 	LIST_ENTRY(in_multi) inm_link;	/* to-be-released by in_ifdetach */
296 	struct	in_addr inm_addr;	/* IP multicast address, convenience */
297 	struct	ifnet *inm_ifp;		/* back pointer to ifnet */
298 	struct	ifmultiaddr *inm_ifma;	/* back pointer to ifmultiaddr */
299 	u_int	inm_timer;		/* IGMPv1/v2 group / v3 query timer */
300 	u_int	inm_state;		/* state of the membership */
301 	void	*inm_rti;		/* unused, legacy field */
302 	u_int	inm_refcount;		/* reference count */
303 
304 	/* New fields for IGMPv3 follow. */
305 	struct igmp_ifsoftc	*inm_igi;	/* IGMP info */
306 	SLIST_ENTRY(in_multi)	 inm_nrele;	/* to-be-released by IGMP */
307 	struct ip_msource_tree	 inm_srcs;	/* tree of sources */
308 	u_long			 inm_nsrc;	/* # of tree entries */
309 
310 	struct mbufq		 inm_scq;	/* queue of pending
311 						 * state-change packets */
312 	struct timeval		 inm_lastgsrtv;	/* Time of last G-S-R query */
313 	uint16_t		 inm_sctimer;	/* state-change timer */
314 	uint16_t		 inm_scrv;	/* state-change rexmit count */
315 
316 	/*
317 	 * SSM state counters which track state at T0 (the time the last
318 	 * state-change report's RV timer went to zero) and T1
319 	 * (time of pending report, i.e. now).
320 	 * Used for computing IGMPv3 state-change reports. Several refcounts
321 	 * are maintained here to optimize for common use-cases.
322 	 */
323 	struct inm_st {
324 		uint16_t	iss_fmode;	/* IGMP filter mode */
325 		uint16_t	iss_asm;	/* # of ASM listeners */
326 		uint16_t	iss_ex;		/* # of exclusive members */
327 		uint16_t	iss_in;		/* # of inclusive members */
328 		uint16_t	iss_rec;	/* # of recorded sources */
329 	}			inm_st[2];	/* state at t0, t1 */
330 };
331 
332 /*
333  * Helper function to derive the filter mode on a source entry
334  * from its internal counters. Predicates are:
335  *  A source is only excluded if all listeners exclude it.
336  *  A source is only included if no listeners exclude it,
337  *  and at least one listener includes it.
338  * May be used by ifmcstat(8).
339  */
340 static __inline uint8_t
341 ims_get_mode(const struct in_multi *inm, const struct ip_msource *ims,
342     uint8_t t)
343 {
344 
345 	t = !!t;
346 	if (inm->inm_st[t].iss_ex > 0 &&
347 	    inm->inm_st[t].iss_ex == ims->ims_st[t].ex)
348 		return (MCAST_EXCLUDE);
349 	else if (ims->ims_st[t].in > 0 && ims->ims_st[t].ex == 0)
350 		return (MCAST_INCLUDE);
351 	return (MCAST_UNDEFINED);
352 }
353 
354 #ifdef SYSCTL_DECL
355 SYSCTL_DECL(_net_inet);
356 SYSCTL_DECL(_net_inet_ip);
357 SYSCTL_DECL(_net_inet_raw);
358 #endif
359 
360 /*
361  * Lock macros for IPv4 layer multicast address lists.  IPv4 lock goes
362  * before link layer multicast locks in the lock order.  In most cases,
363  * consumers of IN_*_MULTI() macros should acquire the locks before
364  * calling them; users of the in_{add,del}multi() functions should not.
365  */
366 extern struct mtx in_multi_list_mtx;
367 extern struct sx in_multi_sx;
368 
369 #define	IN_MULTI_LIST_LOCK()		mtx_lock(&in_multi_list_mtx)
370 #define	IN_MULTI_LIST_UNLOCK()	mtx_unlock(&in_multi_list_mtx)
371 #define	IN_MULTI_LIST_LOCK_ASSERT()	mtx_assert(&in_multi_list_mtx, MA_OWNED)
372 #define	IN_MULTI_LIST_UNLOCK_ASSERT() mtx_assert(&in_multi_list_mtx, MA_NOTOWNED)
373 
374 #define	IN_MULTI_LOCK()		sx_xlock(&in_multi_sx)
375 #define	IN_MULTI_UNLOCK()	sx_xunlock(&in_multi_sx)
376 #define	IN_MULTI_LOCK_ASSERT()	sx_assert(&in_multi_sx, SA_XLOCKED)
377 #define	IN_MULTI_UNLOCK_ASSERT() sx_assert(&in_multi_sx, SA_XUNLOCKED)
378 
379 void inm_disconnect(struct in_multi *inm);
380 
381 /*
382  * Get the in_multi pointer from a ifmultiaddr.
383  * Returns NULL if ifmultiaddr is no longer valid.
384  */
385 static __inline struct in_multi *
386 inm_ifmultiaddr_get_inm(struct ifmultiaddr *ifma)
387 {
388 
389 	NET_EPOCH_ASSERT();
390 
391 	return ((ifma->ifma_addr->sa_family != AF_INET ||
392 	    (ifma->ifma_flags & IFMA_F_ENQUEUED) == 0) ? NULL :
393 	    ifma->ifma_protospec);
394 }
395 
396 /* Acquire an in_multi record. */
397 static __inline void
398 inm_acquire_locked(struct in_multi *inm)
399 {
400 
401 	IN_MULTI_LIST_LOCK_ASSERT();
402 	++inm->inm_refcount;
403 }
404 
405 static __inline void
406 inm_acquire(struct in_multi *inm)
407 {
408 	IN_MULTI_LIST_LOCK();
409 	inm_acquire_locked(inm);
410 	IN_MULTI_LIST_UNLOCK();
411 }
412 
413 static __inline void
414 inm_rele_locked(struct in_multi_head *inmh, struct in_multi *inm)
415 {
416 	MPASS(inm->inm_refcount > 0);
417 	IN_MULTI_LIST_LOCK_ASSERT();
418 
419 	if (--inm->inm_refcount == 0) {
420 		MPASS(inmh != NULL);
421 		inm_disconnect(inm);
422 		inm->inm_ifma->ifma_protospec = NULL;
423 		SLIST_INSERT_HEAD(inmh, inm, inm_nrele);
424 	}
425 }
426 
427 /*
428  * Return values for imo_multi_filter().
429  */
430 #define MCAST_PASS		0	/* Pass */
431 #define MCAST_NOTGMEMBER	1	/* This host not a member of group */
432 #define MCAST_NOTSMEMBER	2	/* This host excluded source */
433 #define MCAST_MUTED		3	/* [deprecated] */
434 
435 struct rib_head;
436 struct	ip_moptions;
437 struct ucred;
438 
439 struct in_multi *inm_lookup_locked(struct ifnet *, const struct in_addr);
440 struct in_multi *inm_lookup(struct ifnet *, const struct in_addr);
441 int	imo_multi_filter(const struct ip_moptions *, const struct ifnet *,
442 	    const struct sockaddr *, const struct sockaddr *);
443 void	inm_commit(struct in_multi *);
444 void	inm_clear_recorded(struct in_multi *);
445 void	inm_print(const struct in_multi *);
446 int	inm_record_source(struct in_multi *inm, const in_addr_t);
447 void	inm_release_deferred(struct in_multi *);
448 void	inm_release_list_deferred(struct in_multi_head *);
449 void	inm_release_wait(void *);
450 int	in_joingroup(struct ifnet *, const struct in_addr *,
451 	    /*const*/ struct in_mfilter *, struct in_multi **);
452 int	in_joingroup_locked(struct ifnet *, const struct in_addr *,
453 	    /*const*/ struct in_mfilter *, struct in_multi **);
454 int	in_leavegroup(struct in_multi *, /*const*/ struct in_mfilter *);
455 int	in_leavegroup_locked(struct in_multi *,
456 	    /*const*/ struct in_mfilter *);
457 int	in_control(struct socket *, u_long, void *, struct ifnet *,
458 	    struct thread *);
459 int	in_control_ioctl(u_long, void *, struct ifnet *,
460 	    struct ucred *);
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