xref: /freebsd/sys/netinet/in_var.h (revision 830940567b49bb0c08dfaed40418999e76616909)
1 /*-
2  * Copyright (c) 1985, 1986, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 4. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  *	@(#)in_var.h	8.2 (Berkeley) 1/9/95
30  * $FreeBSD$
31  */
32 
33 #ifndef _NETINET_IN_VAR_H_
34 #define _NETINET_IN_VAR_H_
35 
36 #include <sys/queue.h>
37 #include <sys/fnv_hash.h>
38 #include <sys/tree.h>
39 
40 struct igmp_ifinfo;
41 struct in_multi;
42 struct lltable;
43 
44 /*
45  * IPv4 per-interface state.
46  */
47 struct in_ifinfo {
48 	struct lltable		*ii_llt;	/* ARP state */
49 	struct igmp_ifinfo	*ii_igmp;	/* IGMP state */
50 	struct in_multi		*ii_allhosts;	/* 224.0.0.1 membership */
51 };
52 
53 /*
54  * Interface address, Internet version.  One of these structures
55  * is allocated for each Internet address on an interface.
56  * The ifaddr structure contains the protocol-independent part
57  * of the structure and is assumed to be first.
58  */
59 struct in_ifaddr {
60 	struct	ifaddr ia_ifa;		/* protocol-independent info */
61 #define	ia_ifp		ia_ifa.ifa_ifp
62 #define ia_flags	ia_ifa.ifa_flags
63 					/* ia_{,sub}net{,mask} in host order */
64 	u_long	ia_net;			/* network number of interface */
65 	u_long	ia_netmask;		/* mask of net part */
66 	u_long	ia_subnet;		/* subnet number, including net */
67 	u_long	ia_subnetmask;		/* mask of subnet part */
68 	struct	in_addr ia_netbroadcast; /* to recognize net broadcasts */
69 	LIST_ENTRY(in_ifaddr) ia_hash;	/* entry in bucket of inet addresses */
70 	TAILQ_ENTRY(in_ifaddr) ia_link;	/* list of internet addresses */
71 	struct	sockaddr_in ia_addr;	/* reserve space for interface name */
72 	struct	sockaddr_in ia_dstaddr; /* reserve space for broadcast addr */
73 #define	ia_broadaddr	ia_dstaddr
74 	struct	sockaddr_in ia_sockmask; /* reserve space for general netmask */
75 };
76 
77 struct	in_aliasreq {
78 	char	ifra_name[IFNAMSIZ];		/* if name, e.g. "en0" */
79 	struct	sockaddr_in ifra_addr;
80 	struct	sockaddr_in ifra_broadaddr;
81 #define ifra_dstaddr ifra_broadaddr
82 	struct	sockaddr_in ifra_mask;
83 };
84 /*
85  * Given a pointer to an in_ifaddr (ifaddr),
86  * return a pointer to the addr as a sockaddr_in.
87  */
88 #define IA_SIN(ia)    (&(((struct in_ifaddr *)(ia))->ia_addr))
89 #define IA_DSTSIN(ia) (&(((struct in_ifaddr *)(ia))->ia_dstaddr))
90 
91 #define IN_LNAOF(in, ifa) \
92 	((ntohl((in).s_addr) & ~((struct in_ifaddr *)(ifa)->ia_subnetmask))
93 
94 
95 #ifdef	_KERNEL
96 extern	u_char	inetctlerrmap[];
97 
98 #define LLTABLE(ifp)	\
99 	((struct in_ifinfo *)(ifp)->if_afdata[AF_INET])->ii_llt
100 /*
101  * Hash table for IP addresses.
102  */
103 TAILQ_HEAD(in_ifaddrhead, in_ifaddr);
104 LIST_HEAD(in_ifaddrhashhead, in_ifaddr);
105 
106 VNET_DECLARE(struct in_ifaddrhashhead *, in_ifaddrhashtbl);
107 VNET_DECLARE(struct in_ifaddrhead, in_ifaddrhead);
108 VNET_DECLARE(u_long, in_ifaddrhmask);		/* mask for hash table */
109 
110 #define	V_in_ifaddrhashtbl	VNET(in_ifaddrhashtbl)
111 #define	V_in_ifaddrhead		VNET(in_ifaddrhead)
112 #define	V_in_ifaddrhmask	VNET(in_ifaddrhmask)
113 
114 #define INADDR_NHASH_LOG2       9
115 #define INADDR_NHASH		(1 << INADDR_NHASH_LOG2)
116 #define INADDR_HASHVAL(x)	fnv_32_buf((&(x)), sizeof(x), FNV1_32_INIT)
117 #define INADDR_HASH(x) \
118 	(&V_in_ifaddrhashtbl[INADDR_HASHVAL(x) & V_in_ifaddrhmask])
119 
120 extern	struct rwlock in_ifaddr_lock;
121 
122 #define	IN_IFADDR_LOCK_ASSERT()	rw_assert(&in_ifaddr_lock, RA_LOCKED)
123 #define	IN_IFADDR_RLOCK()	rw_rlock(&in_ifaddr_lock)
124 #define	IN_IFADDR_RLOCK_ASSERT()	rw_assert(&in_ifaddr_lock, RA_RLOCKED)
125 #define	IN_IFADDR_RUNLOCK()	rw_runlock(&in_ifaddr_lock)
126 #define	IN_IFADDR_WLOCK()	rw_wlock(&in_ifaddr_lock)
127 #define	IN_IFADDR_WLOCK_ASSERT()	rw_assert(&in_ifaddr_lock, RA_WLOCKED)
128 #define	IN_IFADDR_WUNLOCK()	rw_wunlock(&in_ifaddr_lock)
129 
130 /*
131  * Macro for finding the internet address structure (in_ifaddr)
132  * corresponding to one of our IP addresses (in_addr).
133  */
134 #define INADDR_TO_IFADDR(addr, ia) \
135 	/* struct in_addr addr; */ \
136 	/* struct in_ifaddr *ia; */ \
137 do { \
138 \
139 	LIST_FOREACH(ia, INADDR_HASH((addr).s_addr), ia_hash) \
140 		if (IA_SIN(ia)->sin_addr.s_addr == (addr).s_addr) \
141 			break; \
142 } while (0)
143 
144 /*
145  * Macro for finding the interface (ifnet structure) corresponding to one
146  * of our IP addresses.
147  */
148 #define INADDR_TO_IFP(addr, ifp) \
149 	/* struct in_addr addr; */ \
150 	/* struct ifnet *ifp; */ \
151 { \
152 	struct in_ifaddr *ia; \
153 \
154 	INADDR_TO_IFADDR(addr, ia); \
155 	(ifp) = (ia == NULL) ? NULL : ia->ia_ifp; \
156 }
157 
158 /*
159  * Macro for finding the internet address structure (in_ifaddr) corresponding
160  * to a given interface (ifnet structure).
161  */
162 #define IFP_TO_IA(ifp, ia)						\
163 	/* struct ifnet *ifp; */					\
164 	/* struct in_ifaddr *ia; */					\
165 {									\
166 	for ((ia) = TAILQ_FIRST(&V_in_ifaddrhead);			\
167 	    (ia) != NULL && (ia)->ia_ifp != (ifp);			\
168 	    (ia) = TAILQ_NEXT((ia), ia_link))				\
169 		continue;						\
170 	if ((ia) != NULL)						\
171 		ifa_ref(&(ia)->ia_ifa);					\
172 }
173 #endif
174 
175 /*
176  * IP datagram reassembly.
177  */
178 #define	IPREASS_NHASH_LOG2	6
179 #define	IPREASS_NHASH		(1 << IPREASS_NHASH_LOG2)
180 #define	IPREASS_HMASK		(IPREASS_NHASH - 1)
181 #define	IPREASS_HASH(x,y) \
182 	(((((x) & 0xF) | ((((x) >> 8) & 0xF) << 4)) ^ (y)) & IPREASS_HMASK)
183 
184 /*
185  * Legacy IPv4 IGMP per-link structure.
186  */
187 struct router_info {
188 	struct ifnet *rti_ifp;
189 	int    rti_type; /* type of router which is querier on this interface */
190 	int    rti_time; /* # of slow timeouts since last old query */
191 	SLIST_ENTRY(router_info) rti_list;
192 };
193 
194 /*
195  * Per-interface IGMP router version information.
196  */
197 struct igmp_ifinfo {
198 	LIST_ENTRY(igmp_ifinfo) igi_link;
199 	struct ifnet *igi_ifp;	/* interface this instance belongs to */
200 	uint32_t igi_version;	/* IGMPv3 Host Compatibility Mode */
201 	uint32_t igi_v1_timer;	/* IGMPv1 Querier Present timer (s) */
202 	uint32_t igi_v2_timer;	/* IGMPv2 Querier Present timer (s) */
203 	uint32_t igi_v3_timer;	/* IGMPv3 General Query (interface) timer (s)*/
204 	uint32_t igi_flags;	/* IGMP per-interface flags */
205 	uint32_t igi_rv;	/* IGMPv3 Robustness Variable */
206 	uint32_t igi_qi;	/* IGMPv3 Query Interval (s) */
207 	uint32_t igi_qri;	/* IGMPv3 Query Response Interval (s) */
208 	uint32_t igi_uri;	/* IGMPv3 Unsolicited Report Interval (s) */
209 	SLIST_HEAD(,in_multi)	igi_relinmhead; /* released groups */
210 	struct ifqueue	 igi_gq;	/* queue of general query responses */
211 };
212 
213 #define IGIF_SILENT	0x00000001	/* Do not use IGMP on this ifp */
214 #define IGIF_LOOPBACK	0x00000002	/* Send IGMP reports to loopback */
215 
216 /*
217  * IPv4 multicast IGMP-layer source entry.
218  */
219 struct ip_msource {
220 	RB_ENTRY(ip_msource)	ims_link;	/* RB tree links */
221 	in_addr_t		ims_haddr;	/* host byte order */
222 	struct ims_st {
223 		uint16_t	ex;		/* # of exclusive members */
224 		uint16_t	in;		/* # of inclusive members */
225 	}			ims_st[2];	/* state at t0, t1 */
226 	uint8_t			ims_stp;	/* pending query */
227 };
228 
229 /*
230  * IPv4 multicast PCB-layer source entry.
231  */
232 struct in_msource {
233 	RB_ENTRY(ip_msource)	ims_link;	/* RB tree links */
234 	in_addr_t		ims_haddr;	/* host byte order */
235 	uint8_t			imsl_st[2];	/* state before/at commit */
236 };
237 
238 RB_HEAD(ip_msource_tree, ip_msource);	/* define struct ip_msource_tree */
239 
240 static __inline int
241 ip_msource_cmp(const struct ip_msource *a, const struct ip_msource *b)
242 {
243 
244 	if (a->ims_haddr < b->ims_haddr)
245 		return (-1);
246 	if (a->ims_haddr == b->ims_haddr)
247 		return (0);
248 	return (1);
249 }
250 RB_PROTOTYPE(ip_msource_tree, ip_msource, ims_link, ip_msource_cmp);
251 
252 /*
253  * IPv4 multicast PCB-layer group filter descriptor.
254  */
255 struct in_mfilter {
256 	struct ip_msource_tree	imf_sources; /* source list for (S,G) */
257 	u_long			imf_nsrc;    /* # of source entries */
258 	uint8_t			imf_st[2];   /* state before/at commit */
259 };
260 
261 /*
262  * IPv4 group descriptor.
263  *
264  * For every entry on an ifnet's if_multiaddrs list which represents
265  * an IP multicast group, there is one of these structures.
266  *
267  * If any source filters are present, then a node will exist in the RB-tree
268  * to permit fast lookup by source whenever an operation takes place.
269  * This permits pre-order traversal when we issue reports.
270  * Source filter trees are kept separately from the socket layer to
271  * greatly simplify locking.
272  *
273  * When IGMPv3 is active, inm_timer is the response to group query timer.
274  * The state-change timer inm_sctimer is separate; whenever state changes
275  * for the group the state change record is generated and transmitted,
276  * and kept if retransmissions are necessary.
277  *
278  * FUTURE: inm_link is now only used when groups are being purged
279  * on a detaching ifnet. It could be demoted to a SLIST_ENTRY, but
280  * because it is at the very start of the struct, we can't do this
281  * w/o breaking the ABI for ifmcstat.
282  */
283 struct in_multi {
284 	LIST_ENTRY(in_multi) inm_link;	/* to-be-released by in_ifdetach */
285 	struct	in_addr inm_addr;	/* IP multicast address, convenience */
286 	struct	ifnet *inm_ifp;		/* back pointer to ifnet */
287 	struct	ifmultiaddr *inm_ifma;	/* back pointer to ifmultiaddr */
288 	u_int	inm_timer;		/* IGMPv1/v2 group / v3 query timer */
289 	u_int	inm_state;		/* state of the membership */
290 	void	*inm_rti;		/* unused, legacy field */
291 	u_int	inm_refcount;		/* reference count */
292 
293 	/* New fields for IGMPv3 follow. */
294 	struct igmp_ifinfo	*inm_igi;	/* IGMP info */
295 	SLIST_ENTRY(in_multi)	 inm_nrele;	/* to-be-released by IGMP */
296 	struct ip_msource_tree	 inm_srcs;	/* tree of sources */
297 	u_long			 inm_nsrc;	/* # of tree entries */
298 
299 	struct ifqueue		 inm_scq;	/* queue of pending
300 						 * state-change packets */
301 	struct timeval		 inm_lastgsrtv;	/* Time of last G-S-R query */
302 	uint16_t		 inm_sctimer;	/* state-change timer */
303 	uint16_t		 inm_scrv;	/* state-change rexmit count */
304 
305 	/*
306 	 * SSM state counters which track state at T0 (the time the last
307 	 * state-change report's RV timer went to zero) and T1
308 	 * (time of pending report, i.e. now).
309 	 * Used for computing IGMPv3 state-change reports. Several refcounts
310 	 * are maintained here to optimize for common use-cases.
311 	 */
312 	struct inm_st {
313 		uint16_t	iss_fmode;	/* IGMP filter mode */
314 		uint16_t	iss_asm;	/* # of ASM listeners */
315 		uint16_t	iss_ex;		/* # of exclusive members */
316 		uint16_t	iss_in;		/* # of inclusive members */
317 		uint16_t	iss_rec;	/* # of recorded sources */
318 	}			inm_st[2];	/* state at t0, t1 */
319 };
320 
321 /*
322  * Helper function to derive the filter mode on a source entry
323  * from its internal counters. Predicates are:
324  *  A source is only excluded if all listeners exclude it.
325  *  A source is only included if no listeners exclude it,
326  *  and at least one listener includes it.
327  * May be used by ifmcstat(8).
328  */
329 static __inline uint8_t
330 ims_get_mode(const struct in_multi *inm, const struct ip_msource *ims,
331     uint8_t t)
332 {
333 
334 	t = !!t;
335 	if (inm->inm_st[t].iss_ex > 0 &&
336 	    inm->inm_st[t].iss_ex == ims->ims_st[t].ex)
337 		return (MCAST_EXCLUDE);
338 	else if (ims->ims_st[t].in > 0 && ims->ims_st[t].ex == 0)
339 		return (MCAST_INCLUDE);
340 	return (MCAST_UNDEFINED);
341 }
342 
343 #ifdef _KERNEL
344 
345 #ifdef SYSCTL_DECL
346 SYSCTL_DECL(_net_inet);
347 SYSCTL_DECL(_net_inet_ip);
348 SYSCTL_DECL(_net_inet_raw);
349 #endif
350 
351 /*
352  * Lock macros for IPv4 layer multicast address lists.  IPv4 lock goes
353  * before link layer multicast locks in the lock order.  In most cases,
354  * consumers of IN_*_MULTI() macros should acquire the locks before
355  * calling them; users of the in_{add,del}multi() functions should not.
356  */
357 extern struct mtx in_multi_mtx;
358 #define	IN_MULTI_LOCK()		mtx_lock(&in_multi_mtx)
359 #define	IN_MULTI_UNLOCK()	mtx_unlock(&in_multi_mtx)
360 #define	IN_MULTI_LOCK_ASSERT()	mtx_assert(&in_multi_mtx, MA_OWNED)
361 #define	IN_MULTI_UNLOCK_ASSERT() mtx_assert(&in_multi_mtx, MA_NOTOWNED)
362 
363 /*
364  * Function for looking up an in_multi record for an IPv4 multicast address
365  * on a given interface. ifp must be valid. If no record found, return NULL.
366  * The IN_MULTI_LOCK and IF_ADDR_LOCK on ifp must be held.
367  */
368 static __inline struct in_multi *
369 inm_lookup_locked(struct ifnet *ifp, const struct in_addr ina)
370 {
371 	struct ifmultiaddr *ifma;
372 	struct in_multi *inm;
373 
374 	IN_MULTI_LOCK_ASSERT();
375 	IF_ADDR_LOCK_ASSERT(ifp);
376 
377 	inm = NULL;
378 	TAILQ_FOREACH(ifma, &((ifp)->if_multiaddrs), ifma_link) {
379 		if (ifma->ifma_addr->sa_family == AF_INET) {
380 			inm = (struct in_multi *)ifma->ifma_protospec;
381 			if (inm->inm_addr.s_addr == ina.s_addr)
382 				break;
383 			inm = NULL;
384 		}
385 	}
386 	return (inm);
387 }
388 
389 /*
390  * Wrapper for inm_lookup_locked().
391  * The IF_ADDR_LOCK will be taken on ifp and released on return.
392  */
393 static __inline struct in_multi *
394 inm_lookup(struct ifnet *ifp, const struct in_addr ina)
395 {
396 	struct in_multi *inm;
397 
398 	IN_MULTI_LOCK_ASSERT();
399 	IF_ADDR_LOCK(ifp);
400 	inm = inm_lookup_locked(ifp, ina);
401 	IF_ADDR_UNLOCK(ifp);
402 
403 	return (inm);
404 }
405 
406 /* Acquire an in_multi record. */
407 static __inline void
408 inm_acquire_locked(struct in_multi *inm)
409 {
410 
411 	IN_MULTI_LOCK_ASSERT();
412 	++inm->inm_refcount;
413 }
414 
415 /*
416  * Return values for imo_multi_filter().
417  */
418 #define MCAST_PASS		0	/* Pass */
419 #define MCAST_NOTGMEMBER	1	/* This host not a member of group */
420 #define MCAST_NOTSMEMBER	2	/* This host excluded source */
421 #define MCAST_MUTED		3	/* [deprecated] */
422 
423 struct	rtentry;
424 struct	route;
425 struct	ip_moptions;
426 
427 int	imo_multi_filter(const struct ip_moptions *, const struct ifnet *,
428 	    const struct sockaddr *, const struct sockaddr *);
429 void	inm_commit(struct in_multi *);
430 void	inm_clear_recorded(struct in_multi *);
431 void	inm_print(const struct in_multi *);
432 int	inm_record_source(struct in_multi *inm, const in_addr_t);
433 void	inm_release(struct in_multi *);
434 void	inm_release_locked(struct in_multi *);
435 struct	in_multi *
436 	in_addmulti(struct in_addr *, struct ifnet *);
437 void	in_delmulti(struct in_multi *);
438 int	in_joingroup(struct ifnet *, const struct in_addr *,
439 	    /*const*/ struct in_mfilter *, struct in_multi **);
440 int	in_joingroup_locked(struct ifnet *, const struct in_addr *,
441 	    /*const*/ struct in_mfilter *, struct in_multi **);
442 int	in_leavegroup(struct in_multi *, /*const*/ struct in_mfilter *);
443 int	in_leavegroup_locked(struct in_multi *,
444 	    /*const*/ struct in_mfilter *);
445 int	in_control(struct socket *, u_long, caddr_t, struct ifnet *,
446 	    struct thread *);
447 void	in_rtqdrain(void);
448 void	ip_input(struct mbuf *);
449 int	in_ifadown(struct ifaddr *ifa, int);
450 void	in_ifscrub(struct ifnet *, struct in_ifaddr *);
451 struct	mbuf	*ip_fastforward(struct mbuf *);
452 void	*in_domifattach(struct ifnet *);
453 void	in_domifdetach(struct ifnet *, void *);
454 
455 
456 /* XXX */
457 void	 in_rtalloc_ign(struct route *ro, u_long ignflags, u_int fibnum);
458 void	 in_rtalloc(struct route *ro, u_int fibnum);
459 struct rtentry *in_rtalloc1(struct sockaddr *, int, u_long, u_int);
460 void	 in_rtredirect(struct sockaddr *, struct sockaddr *,
461 	    struct sockaddr *, int, struct sockaddr *, u_int);
462 int	 in_rtrequest(int, struct sockaddr *,
463 	    struct sockaddr *, struct sockaddr *, int, struct rtentry **, u_int);
464 
465 #if 0
466 int	 in_rt_getifa(struct rt_addrinfo *, u_int fibnum);
467 int	 in_rtioctl(u_long, caddr_t, u_int);
468 int	 in_rtrequest1(int, struct rt_addrinfo *, struct rtentry **, u_int);
469 #endif
470 #endif /* _KERNEL */
471 
472 /* INET6 stuff */
473 #include <netinet6/in6_var.h>
474 
475 #endif /* _NETINET_IN_VAR_H_ */
476