xref: /freebsd/sys/netinet/in_var.h (revision 87c1627502a5dde91e5284118eec8682b60f27a2)
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 	int	ifra_vhid;
81 };
82 /*
83  * Given a pointer to an in_ifaddr (ifaddr),
84  * return a pointer to the addr as a sockaddr_in.
85  */
86 #define IA_SIN(ia)    (&(((struct in_ifaddr *)(ia))->ia_addr))
87 #define IA_DSTSIN(ia) (&(((struct in_ifaddr *)(ia))->ia_dstaddr))
88 #define IA_MASKSIN(ia) (&(((struct in_ifaddr *)(ia))->ia_sockmask))
89 
90 #define IN_LNAOF(in, ifa) \
91 	((ntohl((in).s_addr) & ~((struct in_ifaddr *)(ifa)->ia_subnetmask))
92 
93 
94 #ifdef	_KERNEL
95 extern	u_char	inetctlerrmap[];
96 
97 #define LLTABLE(ifp)	\
98 	((struct in_ifinfo *)(ifp)->if_afdata[AF_INET])->ii_llt
99 /*
100  * Hash table for IP addresses.
101  */
102 TAILQ_HEAD(in_ifaddrhead, in_ifaddr);
103 LIST_HEAD(in_ifaddrhashhead, in_ifaddr);
104 
105 VNET_DECLARE(struct in_ifaddrhashhead *, in_ifaddrhashtbl);
106 VNET_DECLARE(struct in_ifaddrhead, in_ifaddrhead);
107 VNET_DECLARE(u_long, in_ifaddrhmask);		/* mask for hash table */
108 
109 #define	V_in_ifaddrhashtbl	VNET(in_ifaddrhashtbl)
110 #define	V_in_ifaddrhead		VNET(in_ifaddrhead)
111 #define	V_in_ifaddrhmask	VNET(in_ifaddrhmask)
112 
113 #define INADDR_NHASH_LOG2       9
114 #define INADDR_NHASH		(1 << INADDR_NHASH_LOG2)
115 #define INADDR_HASHVAL(x)	fnv_32_buf((&(x)), sizeof(x), FNV1_32_INIT)
116 #define INADDR_HASH(x) \
117 	(&V_in_ifaddrhashtbl[INADDR_HASHVAL(x) & V_in_ifaddrhmask])
118 
119 extern	struct rwlock in_ifaddr_lock;
120 
121 #define	IN_IFADDR_LOCK_ASSERT()	rw_assert(&in_ifaddr_lock, RA_LOCKED)
122 #define	IN_IFADDR_RLOCK()	rw_rlock(&in_ifaddr_lock)
123 #define	IN_IFADDR_RLOCK_ASSERT()	rw_assert(&in_ifaddr_lock, RA_RLOCKED)
124 #define	IN_IFADDR_RUNLOCK()	rw_runlock(&in_ifaddr_lock)
125 #define	IN_IFADDR_WLOCK()	rw_wlock(&in_ifaddr_lock)
126 #define	IN_IFADDR_WLOCK_ASSERT()	rw_assert(&in_ifaddr_lock, RA_WLOCKED)
127 #define	IN_IFADDR_WUNLOCK()	rw_wunlock(&in_ifaddr_lock)
128 
129 /*
130  * Macro for finding the internet address structure (in_ifaddr)
131  * corresponding to one of our IP addresses (in_addr).
132  */
133 #define INADDR_TO_IFADDR(addr, ia) \
134 	/* struct in_addr addr; */ \
135 	/* struct in_ifaddr *ia; */ \
136 do { \
137 \
138 	LIST_FOREACH(ia, INADDR_HASH((addr).s_addr), ia_hash) \
139 		if (IA_SIN(ia)->sin_addr.s_addr == (addr).s_addr) \
140 			break; \
141 } while (0)
142 
143 /*
144  * Macro for finding the interface (ifnet structure) corresponding to one
145  * of our IP addresses.
146  */
147 #define INADDR_TO_IFP(addr, ifp) \
148 	/* struct in_addr addr; */ \
149 	/* struct ifnet *ifp; */ \
150 { \
151 	struct in_ifaddr *ia; \
152 \
153 	INADDR_TO_IFADDR(addr, ia); \
154 	(ifp) = (ia == NULL) ? NULL : ia->ia_ifp; \
155 }
156 
157 /*
158  * Macro for finding the internet address structure (in_ifaddr) corresponding
159  * to a given interface (ifnet structure).
160  */
161 #define IFP_TO_IA(ifp, ia)						\
162 	/* struct ifnet *ifp; */					\
163 	/* struct in_ifaddr *ia; */					\
164 do {									\
165 	IN_IFADDR_RLOCK();						\
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 	IN_IFADDR_RUNLOCK();						\
173 } while (0)
174 #endif
175 
176 /*
177  * IP datagram reassembly.
178  */
179 #define	IPREASS_NHASH_LOG2	6
180 #define	IPREASS_NHASH		(1 << IPREASS_NHASH_LOG2)
181 #define	IPREASS_HMASK		(IPREASS_NHASH - 1)
182 #define	IPREASS_HASH(x,y) \
183 	(((((x) & 0xF) | ((((x) >> 8) & 0xF) << 4)) ^ (y)) & IPREASS_HMASK)
184 
185 /*
186  * Legacy IPv4 IGMP per-link structure.
187  */
188 struct router_info {
189 	struct ifnet *rti_ifp;
190 	int    rti_type; /* type of router which is querier on this interface */
191 	int    rti_time; /* # of slow timeouts since last old query */
192 	SLIST_ENTRY(router_info) rti_list;
193 };
194 
195 /*
196  * Per-interface IGMP router version information.
197  */
198 struct igmp_ifinfo {
199 	LIST_ENTRY(igmp_ifinfo) igi_link;
200 	struct ifnet *igi_ifp;	/* interface this instance belongs to */
201 	uint32_t igi_version;	/* IGMPv3 Host Compatibility Mode */
202 	uint32_t igi_v1_timer;	/* IGMPv1 Querier Present timer (s) */
203 	uint32_t igi_v2_timer;	/* IGMPv2 Querier Present timer (s) */
204 	uint32_t igi_v3_timer;	/* IGMPv3 General Query (interface) timer (s)*/
205 	uint32_t igi_flags;	/* IGMP per-interface flags */
206 	uint32_t igi_rv;	/* IGMPv3 Robustness Variable */
207 	uint32_t igi_qi;	/* IGMPv3 Query Interval (s) */
208 	uint32_t igi_qri;	/* IGMPv3 Query Response Interval (s) */
209 	uint32_t igi_uri;	/* IGMPv3 Unsolicited Report Interval (s) */
210 	SLIST_HEAD(,in_multi)	igi_relinmhead; /* released groups */
211 	struct ifqueue	 igi_gq;	/* queue of general query responses */
212 };
213 
214 #define IGIF_SILENT	0x00000001	/* Do not use IGMP on this ifp */
215 #define IGIF_LOOPBACK	0x00000002	/* Send IGMP reports to loopback */
216 
217 /*
218  * IPv4 multicast IGMP-layer source entry.
219  */
220 struct ip_msource {
221 	RB_ENTRY(ip_msource)	ims_link;	/* RB tree links */
222 	in_addr_t		ims_haddr;	/* host byte order */
223 	struct ims_st {
224 		uint16_t	ex;		/* # of exclusive members */
225 		uint16_t	in;		/* # of inclusive members */
226 	}			ims_st[2];	/* state at t0, t1 */
227 	uint8_t			ims_stp;	/* pending query */
228 };
229 
230 /*
231  * IPv4 multicast PCB-layer source entry.
232  */
233 struct in_msource {
234 	RB_ENTRY(ip_msource)	ims_link;	/* RB tree links */
235 	in_addr_t		ims_haddr;	/* host byte order */
236 	uint8_t			imsl_st[2];	/* state before/at commit */
237 };
238 
239 RB_HEAD(ip_msource_tree, ip_msource);	/* define struct ip_msource_tree */
240 
241 static __inline int
242 ip_msource_cmp(const struct ip_msource *a, const struct ip_msource *b)
243 {
244 
245 	if (a->ims_haddr < b->ims_haddr)
246 		return (-1);
247 	if (a->ims_haddr == b->ims_haddr)
248 		return (0);
249 	return (1);
250 }
251 RB_PROTOTYPE(ip_msource_tree, ip_msource, ims_link, ip_msource_cmp);
252 
253 /*
254  * IPv4 multicast PCB-layer group filter descriptor.
255  */
256 struct in_mfilter {
257 	struct ip_msource_tree	imf_sources; /* source list for (S,G) */
258 	u_long			imf_nsrc;    /* # of source entries */
259 	uint8_t			imf_st[2];   /* state before/at commit */
260 };
261 
262 /*
263  * IPv4 group descriptor.
264  *
265  * For every entry on an ifnet's if_multiaddrs list which represents
266  * an IP multicast group, there is one of these structures.
267  *
268  * If any source filters are present, then a node will exist in the RB-tree
269  * to permit fast lookup by source whenever an operation takes place.
270  * This permits pre-order traversal when we issue reports.
271  * Source filter trees are kept separately from the socket layer to
272  * greatly simplify locking.
273  *
274  * When IGMPv3 is active, inm_timer is the response to group query timer.
275  * The state-change timer inm_sctimer is separate; whenever state changes
276  * for the group the state change record is generated and transmitted,
277  * and kept if retransmissions are necessary.
278  *
279  * FUTURE: inm_link is now only used when groups are being purged
280  * on a detaching ifnet. It could be demoted to a SLIST_ENTRY, but
281  * because it is at the very start of the struct, we can't do this
282  * w/o breaking the ABI for ifmcstat.
283  */
284 struct in_multi {
285 	LIST_ENTRY(in_multi) inm_link;	/* to-be-released by in_ifdetach */
286 	struct	in_addr inm_addr;	/* IP multicast address, convenience */
287 	struct	ifnet *inm_ifp;		/* back pointer to ifnet */
288 	struct	ifmultiaddr *inm_ifma;	/* back pointer to ifmultiaddr */
289 	u_int	inm_timer;		/* IGMPv1/v2 group / v3 query timer */
290 	u_int	inm_state;		/* state of the membership */
291 	void	*inm_rti;		/* unused, legacy field */
292 	u_int	inm_refcount;		/* reference count */
293 
294 	/* New fields for IGMPv3 follow. */
295 	struct igmp_ifinfo	*inm_igi;	/* IGMP info */
296 	SLIST_ENTRY(in_multi)	 inm_nrele;	/* to-be-released by IGMP */
297 	struct ip_msource_tree	 inm_srcs;	/* tree of sources */
298 	u_long			 inm_nsrc;	/* # of tree entries */
299 
300 	struct ifqueue		 inm_scq;	/* queue of pending
301 						 * state-change packets */
302 	struct timeval		 inm_lastgsrtv;	/* Time of last G-S-R query */
303 	uint16_t		 inm_sctimer;	/* state-change timer */
304 	uint16_t		 inm_scrv;	/* state-change rexmit count */
305 
306 	/*
307 	 * SSM state counters which track state at T0 (the time the last
308 	 * state-change report's RV timer went to zero) and T1
309 	 * (time of pending report, i.e. now).
310 	 * Used for computing IGMPv3 state-change reports. Several refcounts
311 	 * are maintained here to optimize for common use-cases.
312 	 */
313 	struct inm_st {
314 		uint16_t	iss_fmode;	/* IGMP filter mode */
315 		uint16_t	iss_asm;	/* # of ASM listeners */
316 		uint16_t	iss_ex;		/* # of exclusive members */
317 		uint16_t	iss_in;		/* # of inclusive members */
318 		uint16_t	iss_rec;	/* # of recorded sources */
319 	}			inm_st[2];	/* state at t0, t1 */
320 };
321 
322 /*
323  * Helper function to derive the filter mode on a source entry
324  * from its internal counters. Predicates are:
325  *  A source is only excluded if all listeners exclude it.
326  *  A source is only included if no listeners exclude it,
327  *  and at least one listener includes it.
328  * May be used by ifmcstat(8).
329  */
330 static __inline uint8_t
331 ims_get_mode(const struct in_multi *inm, const struct ip_msource *ims,
332     uint8_t t)
333 {
334 
335 	t = !!t;
336 	if (inm->inm_st[t].iss_ex > 0 &&
337 	    inm->inm_st[t].iss_ex == ims->ims_st[t].ex)
338 		return (MCAST_EXCLUDE);
339 	else if (ims->ims_st[t].in > 0 && ims->ims_st[t].ex == 0)
340 		return (MCAST_INCLUDE);
341 	return (MCAST_UNDEFINED);
342 }
343 
344 #ifdef _KERNEL
345 
346 #ifdef SYSCTL_DECL
347 SYSCTL_DECL(_net_inet);
348 SYSCTL_DECL(_net_inet_ip);
349 SYSCTL_DECL(_net_inet_raw);
350 #endif
351 
352 /*
353  * Lock macros for IPv4 layer multicast address lists.  IPv4 lock goes
354  * before link layer multicast locks in the lock order.  In most cases,
355  * consumers of IN_*_MULTI() macros should acquire the locks before
356  * calling them; users of the in_{add,del}multi() functions should not.
357  */
358 extern struct mtx in_multi_mtx;
359 #define	IN_MULTI_LOCK()		mtx_lock(&in_multi_mtx)
360 #define	IN_MULTI_UNLOCK()	mtx_unlock(&in_multi_mtx)
361 #define	IN_MULTI_LOCK_ASSERT()	mtx_assert(&in_multi_mtx, MA_OWNED)
362 #define	IN_MULTI_UNLOCK_ASSERT() mtx_assert(&in_multi_mtx, MA_NOTOWNED)
363 
364 /*
365  * Function for looking up an in_multi record for an IPv4 multicast address
366  * on a given interface. ifp must be valid. If no record found, return NULL.
367  * The IN_MULTI_LOCK and IF_ADDR_LOCK on ifp must be held.
368  */
369 static __inline struct in_multi *
370 inm_lookup_locked(struct ifnet *ifp, const struct in_addr ina)
371 {
372 	struct ifmultiaddr *ifma;
373 	struct in_multi *inm;
374 
375 	IN_MULTI_LOCK_ASSERT();
376 	IF_ADDR_LOCK_ASSERT(ifp);
377 
378 	inm = NULL;
379 	TAILQ_FOREACH(ifma, &((ifp)->if_multiaddrs), ifma_link) {
380 		if (ifma->ifma_addr->sa_family == AF_INET) {
381 			inm = (struct in_multi *)ifma->ifma_protospec;
382 			if (inm->inm_addr.s_addr == ina.s_addr)
383 				break;
384 			inm = NULL;
385 		}
386 	}
387 	return (inm);
388 }
389 
390 /*
391  * Wrapper for inm_lookup_locked().
392  * The IF_ADDR_LOCK will be taken on ifp and released on return.
393  */
394 static __inline struct in_multi *
395 inm_lookup(struct ifnet *ifp, const struct in_addr ina)
396 {
397 	struct in_multi *inm;
398 
399 	IN_MULTI_LOCK_ASSERT();
400 	IF_ADDR_RLOCK(ifp);
401 	inm = inm_lookup_locked(ifp, ina);
402 	IF_ADDR_RUNLOCK(ifp);
403 
404 	return (inm);
405 }
406 
407 /* Acquire an in_multi record. */
408 static __inline void
409 inm_acquire_locked(struct in_multi *inm)
410 {
411 
412 	IN_MULTI_LOCK_ASSERT();
413 	++inm->inm_refcount;
414 }
415 
416 /*
417  * Return values for imo_multi_filter().
418  */
419 #define MCAST_PASS		0	/* Pass */
420 #define MCAST_NOTGMEMBER	1	/* This host not a member of group */
421 #define MCAST_NOTSMEMBER	2	/* This host excluded source */
422 #define MCAST_MUTED		3	/* [deprecated] */
423 
424 struct	rtentry;
425 struct	route;
426 struct	ip_moptions;
427 struct radix_node_head;
428 
429 int	imo_multi_filter(const struct ip_moptions *, const struct ifnet *,
430 	    const struct sockaddr *, const struct sockaddr *);
431 void	inm_commit(struct in_multi *);
432 void	inm_clear_recorded(struct in_multi *);
433 void	inm_print(const struct in_multi *);
434 int	inm_record_source(struct in_multi *inm, const in_addr_t);
435 void	inm_release(struct in_multi *);
436 void	inm_release_locked(struct in_multi *);
437 struct	in_multi *
438 	in_addmulti(struct in_addr *, struct ifnet *);
439 void	in_delmulti(struct in_multi *);
440 int	in_joingroup(struct ifnet *, const struct in_addr *,
441 	    /*const*/ struct in_mfilter *, struct in_multi **);
442 int	in_joingroup_locked(struct ifnet *, const struct in_addr *,
443 	    /*const*/ struct in_mfilter *, struct in_multi **);
444 int	in_leavegroup(struct in_multi *, /*const*/ struct in_mfilter *);
445 int	in_leavegroup_locked(struct in_multi *,
446 	    /*const*/ struct in_mfilter *);
447 int	in_control(struct socket *, u_long, caddr_t, struct ifnet *,
448 	    struct thread *);
449 void	in_rtqdrain(void);
450 int	in_addprefix(struct in_ifaddr *, int);
451 int	in_scrubprefix(struct in_ifaddr *, u_int);
452 void	ip_input(struct mbuf *);
453 int	in_ifadown(struct ifaddr *ifa, int);
454 void	in_ifscrub(struct ifnet *, struct in_ifaddr *, u_int);
455 struct	mbuf	*ip_fastforward(struct mbuf *);
456 void	*in_domifattach(struct ifnet *);
457 void	in_domifdetach(struct ifnet *, void *);
458 
459 
460 /* XXX */
461 void	 in_rtalloc_ign(struct route *ro, u_long ignflags, u_int fibnum);
462 void	 in_rtalloc(struct route *ro, u_int fibnum);
463 struct rtentry *in_rtalloc1(struct sockaddr *, int, u_long, u_int);
464 void	 in_rtredirect(struct sockaddr *, struct sockaddr *,
465 	    struct sockaddr *, int, struct sockaddr *, u_int);
466 int	 in_rtrequest(int, struct sockaddr *,
467 	    struct sockaddr *, struct sockaddr *, int, struct rtentry **, u_int);
468 void	in_setmatchfunc(struct radix_node_head *, int);
469 
470 #if 0
471 int	 in_rt_getifa(struct rt_addrinfo *, u_int fibnum);
472 int	 in_rtioctl(u_long, caddr_t, u_int);
473 int	 in_rtrequest1(int, struct rt_addrinfo *, struct rtentry **, u_int);
474 #endif
475 #endif /* _KERNEL */
476 
477 /* INET6 stuff */
478 #include <netinet6/in6_var.h>
479 
480 #endif /* _NETINET_IN_VAR_H_ */
481