xref: /freebsd/sys/netinet/in_var.h (revision 3f0efe05432b1633991114ca4ca330102a561959)
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 #ifdef _KERNEL
101 #define IN_ARE_MASKED_ADDR_EQUAL(d, a, m)	(		\
102 	((((d).s_addr ^ (a).s_addr) & (m).s_addr)) == 0 )
103 #endif
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 CK_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 /*
128  * Macro for finding the internet address structure (in_ifaddr)
129  * corresponding to one of our IP addresses (in_addr).
130  */
131 #define INADDR_TO_IFADDR(addr, ia) \
132 	/* struct in_addr addr; */ \
133 	/* struct in_ifaddr *ia; */ \
134 do {									\
135 	NET_EPOCH_ASSERT();						\
136 	CK_LIST_FOREACH(ia, INADDR_HASH((addr).s_addr), ia_hash)	\
137 		if (IA_SIN(ia)->sin_addr.s_addr == (addr).s_addr)	\
138 			break;						\
139 } while (0)
140 
141 /*
142  * Macro for finding the interface (ifnet structure) corresponding to one
143  * of our IP addresses.
144  */
145 #define INADDR_TO_IFP(addr, ifp) \
146 	/* struct in_addr addr; */ \
147 	/* struct ifnet *ifp; */ \
148 { \
149 	struct in_ifaddr *ia; \
150 \
151 	INADDR_TO_IFADDR(addr, ia); \
152 	(ifp) = (ia == NULL) ? NULL : ia->ia_ifp; \
153 }
154 
155 /*
156  * Macro for finding the internet address structure (in_ifaddr) corresponding
157  * to a given interface (ifnet structure).
158  */
159 #define IFP_TO_IA(ifp, ia)						\
160 	/* struct ifnet *ifp; */					\
161 	/* struct in_ifaddr *ia; */					\
162 do {									\
163 	NET_EPOCH_ASSERT();						\
164 	for ((ia) = CK_STAILQ_FIRST(&V_in_ifaddrhead);			\
165 	    (ia) != NULL && (ia)->ia_ifp != (ifp);			\
166 	    (ia) = CK_STAILQ_NEXT((ia), ia_link))			\
167 		continue;						\
168 } while (0)
169 
170 /*
171  * Legacy IPv4 IGMP per-link structure.
172  */
173 struct router_info {
174 	struct ifnet *rti_ifp;
175 	int    rti_type; /* type of router which is querier on this interface */
176 	int    rti_time; /* # of slow timeouts since last old query */
177 	SLIST_ENTRY(router_info) rti_list;
178 };
179 
180 /*
181  * IPv4 multicast IGMP-layer source entry.
182  */
183 struct ip_msource {
184 	RB_ENTRY(ip_msource)	ims_link;	/* RB tree links */
185 	in_addr_t		ims_haddr;	/* host byte order */
186 	struct ims_st {
187 		uint16_t	ex;		/* # of exclusive members */
188 		uint16_t	in;		/* # of inclusive members */
189 	}			ims_st[2];	/* state at t0, t1 */
190 	uint8_t			ims_stp;	/* pending query */
191 };
192 
193 /*
194  * IPv4 multicast PCB-layer source entry.
195  */
196 struct in_msource {
197 	RB_ENTRY(ip_msource)	ims_link;	/* RB tree links */
198 	in_addr_t		ims_haddr;	/* host byte order */
199 	uint8_t			imsl_st[2];	/* state before/at commit */
200 };
201 
202 RB_HEAD(ip_msource_tree, ip_msource);	/* define struct ip_msource_tree */
203 
204 static __inline int
205 ip_msource_cmp(const struct ip_msource *a, const struct ip_msource *b)
206 {
207 
208 	if (a->ims_haddr < b->ims_haddr)
209 		return (-1);
210 	if (a->ims_haddr == b->ims_haddr)
211 		return (0);
212 	return (1);
213 }
214 RB_PROTOTYPE(ip_msource_tree, ip_msource, ims_link, ip_msource_cmp);
215 
216 /*
217  * IPv4 multicast PCB-layer group filter descriptor.
218  */
219 struct in_mfilter {
220 	struct ip_msource_tree	imf_sources; /* source list for (S,G) */
221 	u_long			imf_nsrc;    /* # of source entries */
222 	uint8_t			imf_st[2];   /* state before/at commit */
223 	struct in_multi	       *imf_inm;     /* associated multicast address */
224 	STAILQ_ENTRY(in_mfilter) imf_entry;  /* list entry */
225 };
226 
227 /*
228  * Helper types and functions for IPv4 multicast filters.
229  */
230 STAILQ_HEAD(ip_mfilter_head, in_mfilter);
231 
232 struct in_mfilter *ip_mfilter_alloc(int mflags, int st0, int st1);
233 void ip_mfilter_free(struct in_mfilter *);
234 
235 static inline void
236 ip_mfilter_init(struct ip_mfilter_head *head)
237 {
238 
239 	STAILQ_INIT(head);
240 }
241 
242 static inline struct in_mfilter *
243 ip_mfilter_first(const struct ip_mfilter_head *head)
244 {
245 
246 	return (STAILQ_FIRST(head));
247 }
248 
249 static inline void
250 ip_mfilter_insert(struct ip_mfilter_head *head, struct in_mfilter *imf)
251 {
252 
253 	STAILQ_INSERT_TAIL(head, imf, imf_entry);
254 }
255 
256 static inline void
257 ip_mfilter_remove(struct ip_mfilter_head *head, struct in_mfilter *imf)
258 {
259 
260 	STAILQ_REMOVE(head, imf, in_mfilter, imf_entry);
261 }
262 
263 #define	IP_MFILTER_FOREACH(imf, head) \
264 	STAILQ_FOREACH(imf, head, imf_entry)
265 
266 static inline size_t
267 ip_mfilter_count(struct ip_mfilter_head *head)
268 {
269 	struct in_mfilter *imf;
270 	size_t num = 0;
271 
272 	STAILQ_FOREACH(imf, head, imf_entry)
273 		num++;
274 	return (num);
275 }
276 
277 /*
278  * IPv4 group descriptor.
279  *
280  * For every entry on an ifnet's if_multiaddrs list which represents
281  * an IP multicast group, there is one of these structures.
282  *
283  * If any source filters are present, then a node will exist in the RB-tree
284  * to permit fast lookup by source whenever an operation takes place.
285  * This permits pre-order traversal when we issue reports.
286  * Source filter trees are kept separately from the socket layer to
287  * greatly simplify locking.
288  *
289  * When IGMPv3 is active, inm_timer is the response to group query timer.
290  * The state-change timer inm_sctimer is separate; whenever state changes
291  * for the group the state change record is generated and transmitted,
292  * and kept if retransmissions are necessary.
293  *
294  * FUTURE: inm_link is now only used when groups are being purged
295  * on a detaching ifnet. It could be demoted to a SLIST_ENTRY, but
296  * because it is at the very start of the struct, we can't do this
297  * w/o breaking the ABI for ifmcstat.
298  */
299 struct in_multi {
300 	LIST_ENTRY(in_multi) inm_link;	/* to-be-released by in_ifdetach */
301 	struct	in_addr inm_addr;	/* IP multicast address, convenience */
302 	struct	ifnet *inm_ifp;		/* back pointer to ifnet */
303 	struct	ifmultiaddr *inm_ifma;	/* back pointer to ifmultiaddr */
304 	u_int	inm_timer;		/* IGMPv1/v2 group / v3 query timer */
305 	u_int	inm_state;		/* state of the membership */
306 	void	*inm_rti;		/* unused, legacy field */
307 	u_int	inm_refcount;		/* reference count */
308 
309 	/* New fields for IGMPv3 follow. */
310 	struct igmp_ifsoftc	*inm_igi;	/* IGMP info */
311 	SLIST_ENTRY(in_multi)	 inm_nrele;	/* to-be-released by IGMP */
312 	struct ip_msource_tree	 inm_srcs;	/* tree of sources */
313 	u_long			 inm_nsrc;	/* # of tree entries */
314 
315 	struct mbufq		 inm_scq;	/* queue of pending
316 						 * state-change packets */
317 	struct timeval		 inm_lastgsrtv;	/* Time of last G-S-R query */
318 	uint16_t		 inm_sctimer;	/* state-change timer */
319 	uint16_t		 inm_scrv;	/* state-change rexmit count */
320 
321 	/*
322 	 * SSM state counters which track state at T0 (the time the last
323 	 * state-change report's RV timer went to zero) and T1
324 	 * (time of pending report, i.e. now).
325 	 * Used for computing IGMPv3 state-change reports. Several refcounts
326 	 * are maintained here to optimize for common use-cases.
327 	 */
328 	struct inm_st {
329 		uint16_t	iss_fmode;	/* IGMP filter mode */
330 		uint16_t	iss_asm;	/* # of ASM listeners */
331 		uint16_t	iss_ex;		/* # of exclusive members */
332 		uint16_t	iss_in;		/* # of inclusive members */
333 		uint16_t	iss_rec;	/* # of recorded sources */
334 	}			inm_st[2];	/* state at t0, t1 */
335 };
336 
337 /*
338  * Helper function to derive the filter mode on a source entry
339  * from its internal counters. Predicates are:
340  *  A source is only excluded if all listeners exclude it.
341  *  A source is only included if no listeners exclude it,
342  *  and at least one listener includes it.
343  * May be used by ifmcstat(8).
344  */
345 static __inline uint8_t
346 ims_get_mode(const struct in_multi *inm, const struct ip_msource *ims,
347     uint8_t t)
348 {
349 
350 	t = !!t;
351 	if (inm->inm_st[t].iss_ex > 0 &&
352 	    inm->inm_st[t].iss_ex == ims->ims_st[t].ex)
353 		return (MCAST_EXCLUDE);
354 	else if (ims->ims_st[t].in > 0 && ims->ims_st[t].ex == 0)
355 		return (MCAST_INCLUDE);
356 	return (MCAST_UNDEFINED);
357 }
358 
359 #ifdef SYSCTL_DECL
360 SYSCTL_DECL(_net_inet);
361 SYSCTL_DECL(_net_inet_ip);
362 SYSCTL_DECL(_net_inet_raw);
363 #endif
364 
365 /*
366  * Lock macros for IPv4 layer multicast address lists.  IPv4 lock goes
367  * before link layer multicast locks in the lock order.  In most cases,
368  * consumers of IN_*_MULTI() macros should acquire the locks before
369  * calling them; users of the in_{add,del}multi() functions should not.
370  */
371 extern struct mtx in_multi_list_mtx;
372 extern struct sx in_multi_sx;
373 
374 #define	IN_MULTI_LIST_LOCK()		mtx_lock(&in_multi_list_mtx)
375 #define	IN_MULTI_LIST_UNLOCK()	mtx_unlock(&in_multi_list_mtx)
376 #define	IN_MULTI_LIST_LOCK_ASSERT()	mtx_assert(&in_multi_list_mtx, MA_OWNED)
377 #define	IN_MULTI_LIST_UNLOCK_ASSERT() mtx_assert(&in_multi_list_mtx, MA_NOTOWNED)
378 
379 #define	IN_MULTI_LOCK()		sx_xlock(&in_multi_sx)
380 #define	IN_MULTI_UNLOCK()	sx_xunlock(&in_multi_sx)
381 #define	IN_MULTI_LOCK_ASSERT()	sx_assert(&in_multi_sx, SA_XLOCKED)
382 #define	IN_MULTI_UNLOCK_ASSERT() sx_assert(&in_multi_sx, SA_XUNLOCKED)
383 
384 void inm_disconnect(struct in_multi *inm);
385 
386 /*
387  * Get the in_multi pointer from a ifmultiaddr.
388  * Returns NULL if ifmultiaddr is no longer valid.
389  */
390 static __inline struct in_multi *
391 inm_ifmultiaddr_get_inm(struct ifmultiaddr *ifma)
392 {
393 
394 	NET_EPOCH_ASSERT();
395 
396 	return ((ifma->ifma_addr->sa_family != AF_INET ||
397 	    (ifma->ifma_flags & IFMA_F_ENQUEUED) == 0) ? NULL :
398 	    ifma->ifma_protospec);
399 }
400 
401 /* Acquire an in_multi record. */
402 static __inline void
403 inm_acquire_locked(struct in_multi *inm)
404 {
405 
406 	IN_MULTI_LIST_LOCK_ASSERT();
407 	++inm->inm_refcount;
408 }
409 
410 static __inline void
411 inm_acquire(struct in_multi *inm)
412 {
413 	IN_MULTI_LIST_LOCK();
414 	inm_acquire_locked(inm);
415 	IN_MULTI_LIST_UNLOCK();
416 }
417 
418 static __inline void
419 inm_rele_locked(struct in_multi_head *inmh, struct in_multi *inm)
420 {
421 	MPASS(inm->inm_refcount > 0);
422 	IN_MULTI_LIST_LOCK_ASSERT();
423 
424 	if (--inm->inm_refcount == 0) {
425 		MPASS(inmh != NULL);
426 		inm_disconnect(inm);
427 		inm->inm_ifma->ifma_protospec = NULL;
428 		SLIST_INSERT_HEAD(inmh, inm, inm_nrele);
429 	}
430 }
431 
432 /*
433  * Return values for imo_multi_filter().
434  */
435 #define MCAST_PASS		0	/* Pass */
436 #define MCAST_NOTGMEMBER	1	/* This host not a member of group */
437 #define MCAST_NOTSMEMBER	2	/* This host excluded source */
438 #define MCAST_MUTED		3	/* [deprecated] */
439 
440 struct rib_head;
441 struct	ip_moptions;
442 struct ucred;
443 
444 struct in_multi *inm_lookup_locked(struct ifnet *, const struct in_addr);
445 struct in_multi *inm_lookup(struct ifnet *, const struct in_addr);
446 int	imo_multi_filter(const struct ip_moptions *, const struct ifnet *,
447 	    const struct sockaddr *, const struct sockaddr *);
448 void	inm_commit(struct in_multi *);
449 void	inm_clear_recorded(struct in_multi *);
450 void	inm_print(const struct in_multi *);
451 int	inm_record_source(struct in_multi *inm, const in_addr_t);
452 void	inm_release_deferred(struct in_multi *);
453 void	inm_release_list_deferred(struct in_multi_head *);
454 void	inm_release_wait(void *);
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, void *, struct ifnet *,
463 	    struct thread *);
464 int	in_control_ioctl(u_long, void *, struct ifnet *,
465 	    struct ucred *);
466 int	in_addprefix(struct in_ifaddr *);
467 int	in_scrubprefix(struct in_ifaddr *, u_int);
468 void	in_ifscrub_all(void);
469 void	ip_input(struct mbuf *);
470 void	ip_direct_input(struct mbuf *);
471 void	in_ifadown(struct ifaddr *ifa, int);
472 struct	mbuf	*ip_tryforward(struct mbuf *);
473 void	*in_domifattach(struct ifnet *);
474 void	in_domifdetach(struct ifnet *, void *);
475 struct rib_head *in_inithead(uint32_t fibnum);
476 #ifdef VIMAGE
477 void	in_detachhead(struct rib_head *rh);
478 #endif
479 
480 #endif /* _KERNEL */
481 
482 /* INET6 stuff */
483 #include <netinet6/in6_var.h>
484 
485 #endif /* _NETINET_IN_VAR_H_ */
486