xref: /freebsd/sys/netinet/in_var.h (revision 10b59a9b4add0320d52c15ce057dd697261e7dfc)
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_subnet{,mask} in host order */
64 	u_long	ia_subnet;		/* subnet address */
65 	u_long	ia_subnetmask;		/* mask of subnet */
66 	LIST_ENTRY(in_ifaddr) ia_hash;	/* entry in bucket of inet addresses */
67 	TAILQ_ENTRY(in_ifaddr) ia_link;	/* list of internet addresses */
68 	struct	sockaddr_in ia_addr;	/* reserve space for interface name */
69 	struct	sockaddr_in ia_dstaddr; /* reserve space for broadcast addr */
70 #define	ia_broadaddr	ia_dstaddr
71 	struct	sockaddr_in ia_sockmask; /* reserve space for general netmask */
72 };
73 
74 struct	in_aliasreq {
75 	char	ifra_name[IFNAMSIZ];		/* if name, e.g. "en0" */
76 	struct	sockaddr_in ifra_addr;
77 	struct	sockaddr_in ifra_broadaddr;
78 #define ifra_dstaddr ifra_broadaddr
79 	struct	sockaddr_in ifra_mask;
80 };
81 /*
82  * Given a pointer to an in_ifaddr (ifaddr),
83  * return a pointer to the addr as a sockaddr_in.
84  */
85 #define IA_SIN(ia)    (&(((struct in_ifaddr *)(ia))->ia_addr))
86 #define IA_DSTSIN(ia) (&(((struct in_ifaddr *)(ia))->ia_dstaddr))
87 
88 #define IN_LNAOF(in, ifa) \
89 	((ntohl((in).s_addr) & ~((struct in_ifaddr *)(ifa)->ia_subnetmask))
90 
91 
92 #ifdef	_KERNEL
93 extern	u_char	inetctlerrmap[];
94 
95 #define LLTABLE(ifp)	\
96 	((struct in_ifinfo *)(ifp)->if_afdata[AF_INET])->ii_llt
97 /*
98  * Hash table for IP addresses.
99  */
100 TAILQ_HEAD(in_ifaddrhead, in_ifaddr);
101 LIST_HEAD(in_ifaddrhashhead, in_ifaddr);
102 
103 VNET_DECLARE(struct in_ifaddrhashhead *, in_ifaddrhashtbl);
104 VNET_DECLARE(struct in_ifaddrhead, in_ifaddrhead);
105 VNET_DECLARE(u_long, in_ifaddrhmask);		/* mask for hash table */
106 
107 #define	V_in_ifaddrhashtbl	VNET(in_ifaddrhashtbl)
108 #define	V_in_ifaddrhead		VNET(in_ifaddrhead)
109 #define	V_in_ifaddrhmask	VNET(in_ifaddrhmask)
110 
111 #define INADDR_NHASH_LOG2       9
112 #define INADDR_NHASH		(1 << INADDR_NHASH_LOG2)
113 #define INADDR_HASHVAL(x)	fnv_32_buf((&(x)), sizeof(x), FNV1_32_INIT)
114 #define INADDR_HASH(x) \
115 	(&V_in_ifaddrhashtbl[INADDR_HASHVAL(x) & V_in_ifaddrhmask])
116 
117 extern	struct rwlock in_ifaddr_lock;
118 
119 #define	IN_IFADDR_LOCK_ASSERT()	rw_assert(&in_ifaddr_lock, RA_LOCKED)
120 #define	IN_IFADDR_RLOCK()	rw_rlock(&in_ifaddr_lock)
121 #define	IN_IFADDR_RLOCK_ASSERT()	rw_assert(&in_ifaddr_lock, RA_RLOCKED)
122 #define	IN_IFADDR_RUNLOCK()	rw_runlock(&in_ifaddr_lock)
123 #define	IN_IFADDR_WLOCK()	rw_wlock(&in_ifaddr_lock)
124 #define	IN_IFADDR_WLOCK_ASSERT()	rw_assert(&in_ifaddr_lock, RA_WLOCKED)
125 #define	IN_IFADDR_WUNLOCK()	rw_wunlock(&in_ifaddr_lock)
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 \
136 	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 {									\
163 	for ((ia) = TAILQ_FIRST(&V_in_ifaddrhead);			\
164 	    (ia) != NULL && (ia)->ia_ifp != (ifp);			\
165 	    (ia) = TAILQ_NEXT((ia), ia_link))				\
166 		continue;						\
167 	if ((ia) != NULL)						\
168 		ifa_ref(&(ia)->ia_ifa);					\
169 }
170 #endif
171 
172 /*
173  * IP datagram reassembly.
174  */
175 #define	IPREASS_NHASH_LOG2	6
176 #define	IPREASS_NHASH		(1 << IPREASS_NHASH_LOG2)
177 #define	IPREASS_HMASK		(IPREASS_NHASH - 1)
178 #define	IPREASS_HASH(x,y) \
179 	(((((x) & 0xF) | ((((x) >> 8) & 0xF) << 4)) ^ (y)) & IPREASS_HMASK)
180 
181 /*
182  * Legacy IPv4 IGMP per-link structure.
183  */
184 struct router_info {
185 	struct ifnet *rti_ifp;
186 	int    rti_type; /* type of router which is querier on this interface */
187 	int    rti_time; /* # of slow timeouts since last old query */
188 	SLIST_ENTRY(router_info) rti_list;
189 };
190 
191 /*
192  * Per-interface IGMP router version information.
193  */
194 struct igmp_ifinfo {
195 	LIST_ENTRY(igmp_ifinfo) igi_link;
196 	struct ifnet *igi_ifp;	/* interface this instance belongs to */
197 	uint32_t igi_version;	/* IGMPv3 Host Compatibility Mode */
198 	uint32_t igi_v1_timer;	/* IGMPv1 Querier Present timer (s) */
199 	uint32_t igi_v2_timer;	/* IGMPv2 Querier Present timer (s) */
200 	uint32_t igi_v3_timer;	/* IGMPv3 General Query (interface) timer (s)*/
201 	uint32_t igi_flags;	/* IGMP per-interface flags */
202 	uint32_t igi_rv;	/* IGMPv3 Robustness Variable */
203 	uint32_t igi_qi;	/* IGMPv3 Query Interval (s) */
204 	uint32_t igi_qri;	/* IGMPv3 Query Response Interval (s) */
205 	uint32_t igi_uri;	/* IGMPv3 Unsolicited Report Interval (s) */
206 	SLIST_HEAD(,in_multi)	igi_relinmhead; /* released groups */
207 	struct ifqueue	 igi_gq;	/* queue of general query responses */
208 };
209 
210 #define IGIF_SILENT	0x00000001	/* Do not use IGMP on this ifp */
211 #define IGIF_LOOPBACK	0x00000002	/* Send IGMP reports to loopback */
212 
213 /*
214  * IPv4 multicast IGMP-layer source entry.
215  */
216 struct ip_msource {
217 	RB_ENTRY(ip_msource)	ims_link;	/* RB tree links */
218 	in_addr_t		ims_haddr;	/* host byte order */
219 	struct ims_st {
220 		uint16_t	ex;		/* # of exclusive members */
221 		uint16_t	in;		/* # of inclusive members */
222 	}			ims_st[2];	/* state at t0, t1 */
223 	uint8_t			ims_stp;	/* pending query */
224 };
225 
226 /*
227  * IPv4 multicast PCB-layer source entry.
228  */
229 struct in_msource {
230 	RB_ENTRY(ip_msource)	ims_link;	/* RB tree links */
231 	in_addr_t		ims_haddr;	/* host byte order */
232 	uint8_t			imsl_st[2];	/* state before/at commit */
233 };
234 
235 RB_HEAD(ip_msource_tree, ip_msource);	/* define struct ip_msource_tree */
236 
237 static __inline int
238 ip_msource_cmp(const struct ip_msource *a, const struct ip_msource *b)
239 {
240 
241 	if (a->ims_haddr < b->ims_haddr)
242 		return (-1);
243 	if (a->ims_haddr == b->ims_haddr)
244 		return (0);
245 	return (1);
246 }
247 RB_PROTOTYPE(ip_msource_tree, ip_msource, ims_link, ip_msource_cmp);
248 
249 /*
250  * IPv4 multicast PCB-layer group filter descriptor.
251  */
252 struct in_mfilter {
253 	struct ip_msource_tree	imf_sources; /* source list for (S,G) */
254 	u_long			imf_nsrc;    /* # of source entries */
255 	uint8_t			imf_st[2];   /* state before/at commit */
256 };
257 
258 /*
259  * IPv4 group descriptor.
260  *
261  * For every entry on an ifnet's if_multiaddrs list which represents
262  * an IP multicast group, there is one of these structures.
263  *
264  * If any source filters are present, then a node will exist in the RB-tree
265  * to permit fast lookup by source whenever an operation takes place.
266  * This permits pre-order traversal when we issue reports.
267  * Source filter trees are kept separately from the socket layer to
268  * greatly simplify locking.
269  *
270  * When IGMPv3 is active, inm_timer is the response to group query timer.
271  * The state-change timer inm_sctimer is separate; whenever state changes
272  * for the group the state change record is generated and transmitted,
273  * and kept if retransmissions are necessary.
274  *
275  * FUTURE: inm_link is now only used when groups are being purged
276  * on a detaching ifnet. It could be demoted to a SLIST_ENTRY, but
277  * because it is at the very start of the struct, we can't do this
278  * w/o breaking the ABI for ifmcstat.
279  */
280 struct in_multi {
281 	LIST_ENTRY(in_multi) inm_link;	/* to-be-released by in_ifdetach */
282 	struct	in_addr inm_addr;	/* IP multicast address, convenience */
283 	struct	ifnet *inm_ifp;		/* back pointer to ifnet */
284 	struct	ifmultiaddr *inm_ifma;	/* back pointer to ifmultiaddr */
285 	u_int	inm_timer;		/* IGMPv1/v2 group / v3 query timer */
286 	u_int	inm_state;		/* state of the membership */
287 	void	*inm_rti;		/* unused, legacy field */
288 	u_int	inm_refcount;		/* reference count */
289 
290 	/* New fields for IGMPv3 follow. */
291 	struct igmp_ifinfo	*inm_igi;	/* IGMP info */
292 	SLIST_ENTRY(in_multi)	 inm_nrele;	/* to-be-released by IGMP */
293 	struct ip_msource_tree	 inm_srcs;	/* tree of sources */
294 	u_long			 inm_nsrc;	/* # of tree entries */
295 
296 	struct ifqueue		 inm_scq;	/* queue of pending
297 						 * state-change packets */
298 	struct timeval		 inm_lastgsrtv;	/* Time of last G-S-R query */
299 	uint16_t		 inm_sctimer;	/* state-change timer */
300 	uint16_t		 inm_scrv;	/* state-change rexmit count */
301 
302 	/*
303 	 * SSM state counters which track state at T0 (the time the last
304 	 * state-change report's RV timer went to zero) and T1
305 	 * (time of pending report, i.e. now).
306 	 * Used for computing IGMPv3 state-change reports. Several refcounts
307 	 * are maintained here to optimize for common use-cases.
308 	 */
309 	struct inm_st {
310 		uint16_t	iss_fmode;	/* IGMP filter mode */
311 		uint16_t	iss_asm;	/* # of ASM listeners */
312 		uint16_t	iss_ex;		/* # of exclusive members */
313 		uint16_t	iss_in;		/* # of inclusive members */
314 		uint16_t	iss_rec;	/* # of recorded sources */
315 	}			inm_st[2];	/* state at t0, t1 */
316 };
317 
318 /*
319  * Helper function to derive the filter mode on a source entry
320  * from its internal counters. Predicates are:
321  *  A source is only excluded if all listeners exclude it.
322  *  A source is only included if no listeners exclude it,
323  *  and at least one listener includes it.
324  * May be used by ifmcstat(8).
325  */
326 static __inline uint8_t
327 ims_get_mode(const struct in_multi *inm, const struct ip_msource *ims,
328     uint8_t t)
329 {
330 
331 	t = !!t;
332 	if (inm->inm_st[t].iss_ex > 0 &&
333 	    inm->inm_st[t].iss_ex == ims->ims_st[t].ex)
334 		return (MCAST_EXCLUDE);
335 	else if (ims->ims_st[t].in > 0 && ims->ims_st[t].ex == 0)
336 		return (MCAST_INCLUDE);
337 	return (MCAST_UNDEFINED);
338 }
339 
340 #ifdef _KERNEL
341 
342 #ifdef SYSCTL_DECL
343 SYSCTL_DECL(_net_inet);
344 SYSCTL_DECL(_net_inet_ip);
345 SYSCTL_DECL(_net_inet_raw);
346 #endif
347 
348 /*
349  * Lock macros for IPv4 layer multicast address lists.  IPv4 lock goes
350  * before link layer multicast locks in the lock order.  In most cases,
351  * consumers of IN_*_MULTI() macros should acquire the locks before
352  * calling them; users of the in_{add,del}multi() functions should not.
353  */
354 extern struct mtx in_multi_mtx;
355 #define	IN_MULTI_LOCK()		mtx_lock(&in_multi_mtx)
356 #define	IN_MULTI_UNLOCK()	mtx_unlock(&in_multi_mtx)
357 #define	IN_MULTI_LOCK_ASSERT()	mtx_assert(&in_multi_mtx, MA_OWNED)
358 #define	IN_MULTI_UNLOCK_ASSERT() mtx_assert(&in_multi_mtx, MA_NOTOWNED)
359 
360 /*
361  * Function for looking up an in_multi record for an IPv4 multicast address
362  * on a given interface. ifp must be valid. If no record found, return NULL.
363  * The IN_MULTI_LOCK and IF_ADDR_LOCK on ifp must be held.
364  */
365 static __inline struct in_multi *
366 inm_lookup_locked(struct ifnet *ifp, const struct in_addr ina)
367 {
368 	struct ifmultiaddr *ifma;
369 	struct in_multi *inm;
370 
371 	IN_MULTI_LOCK_ASSERT();
372 	IF_ADDR_LOCK_ASSERT(ifp);
373 
374 	inm = NULL;
375 	TAILQ_FOREACH(ifma, &((ifp)->if_multiaddrs), ifma_link) {
376 		if (ifma->ifma_addr->sa_family == AF_INET) {
377 			inm = (struct in_multi *)ifma->ifma_protospec;
378 			if (inm->inm_addr.s_addr == ina.s_addr)
379 				break;
380 			inm = NULL;
381 		}
382 	}
383 	return (inm);
384 }
385 
386 /*
387  * Wrapper for inm_lookup_locked().
388  * The IF_ADDR_LOCK will be taken on ifp and released on return.
389  */
390 static __inline struct in_multi *
391 inm_lookup(struct ifnet *ifp, const struct in_addr ina)
392 {
393 	struct in_multi *inm;
394 
395 	IN_MULTI_LOCK_ASSERT();
396 	IF_ADDR_LOCK(ifp);
397 	inm = inm_lookup_locked(ifp, ina);
398 	IF_ADDR_UNLOCK(ifp);
399 
400 	return (inm);
401 }
402 
403 /* Acquire an in_multi record. */
404 static __inline void
405 inm_acquire_locked(struct in_multi *inm)
406 {
407 
408 	IN_MULTI_LOCK_ASSERT();
409 	++inm->inm_refcount;
410 }
411 
412 /*
413  * Return values for imo_multi_filter().
414  */
415 #define MCAST_PASS		0	/* Pass */
416 #define MCAST_NOTGMEMBER	1	/* This host not a member of group */
417 #define MCAST_NOTSMEMBER	2	/* This host excluded source */
418 #define MCAST_MUTED		3	/* [deprecated] */
419 
420 struct	rtentry;
421 struct	route;
422 struct	ip_moptions;
423 
424 int	imo_multi_filter(const struct ip_moptions *, const struct ifnet *,
425 	    const struct sockaddr *, const struct sockaddr *);
426 void	inm_commit(struct in_multi *);
427 void	inm_clear_recorded(struct in_multi *);
428 void	inm_print(const struct in_multi *);
429 int	inm_record_source(struct in_multi *inm, const in_addr_t);
430 void	inm_release(struct in_multi *);
431 void	inm_release_locked(struct in_multi *);
432 struct	in_multi *
433 	in_addmulti(struct in_addr *, struct ifnet *);
434 void	in_delmulti(struct in_multi *);
435 int	in_joingroup(struct ifnet *, const struct in_addr *,
436 	    /*const*/ struct in_mfilter *, struct in_multi **);
437 int	in_joingroup_locked(struct ifnet *, const struct in_addr *,
438 	    /*const*/ struct in_mfilter *, struct in_multi **);
439 int	in_leavegroup(struct in_multi *, /*const*/ struct in_mfilter *);
440 int	in_leavegroup_locked(struct in_multi *,
441 	    /*const*/ struct in_mfilter *);
442 int	in_control(struct socket *, u_long, caddr_t, struct ifnet *,
443 	    struct thread *);
444 void	in_rtqdrain(void);
445 void	ip_input(struct mbuf *);
446 int	in_ifadown(struct ifaddr *ifa, int);
447 void	in_ifscrub(struct ifnet *, struct in_ifaddr *, u_int);
448 struct	mbuf	*ip_fastforward(struct mbuf *);
449 void	*in_domifattach(struct ifnet *);
450 void	in_domifdetach(struct ifnet *, void *);
451 
452 
453 /* XXX */
454 void	 in_rtalloc_ign(struct route *ro, u_long ignflags, u_int fibnum);
455 void	 in_rtalloc(struct route *ro, u_int fibnum);
456 struct rtentry *in_rtalloc1(struct sockaddr *, int, u_long, u_int);
457 void	 in_rtredirect(struct sockaddr *, struct sockaddr *,
458 	    struct sockaddr *, int, struct sockaddr *, u_int);
459 int	 in_rtrequest(int, struct sockaddr *,
460 	    struct sockaddr *, struct sockaddr *, int, struct rtentry **, u_int);
461 
462 #if 0
463 int	 in_rt_getifa(struct rt_addrinfo *, u_int fibnum);
464 int	 in_rtioctl(u_long, caddr_t, u_int);
465 int	 in_rtrequest1(int, struct rt_addrinfo *, struct rtentry **, u_int);
466 #endif
467 #endif /* _KERNEL */
468 
469 /* INET6 stuff */
470 #include <netinet6/in6_var.h>
471 
472 #endif /* _NETINET_IN_VAR_H_ */
473