xref: /freebsd/sys/netinet/in_var.h (revision dc60165b73e4c4d829a2cb9fed5cce585e93d9a9)
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 /*
99  * Hash table for IP addresses.
100  */
101 TAILQ_HEAD(in_ifaddrhead, in_ifaddr);
102 LIST_HEAD(in_ifaddrhashhead, in_ifaddr);
103 #ifdef VIMAGE_GLOBALS
104 extern	struct in_ifaddrhashhead *in_ifaddrhashtbl;
105 extern	struct in_ifaddrhead in_ifaddrhead;
106 extern	u_long in_ifaddrhmask;			/* mask for hash table */
107 #endif
108 
109 #define INADDR_NHASH_LOG2       9
110 #define INADDR_NHASH		(1 << INADDR_NHASH_LOG2)
111 #define INADDR_HASHVAL(x)	fnv_32_buf((&(x)), sizeof(x), FNV1_32_INIT)
112 #define INADDR_HASH(x) \
113 	(&V_in_ifaddrhashtbl[INADDR_HASHVAL(x) & V_in_ifaddrhmask])
114 
115 /*
116  * Macro for finding the internet address structure (in_ifaddr)
117  * corresponding to one of our IP addresses (in_addr).
118  */
119 #define INADDR_TO_IFADDR(addr, ia) \
120 	/* struct in_addr addr; */ \
121 	/* struct in_ifaddr *ia; */ \
122 do { \
123 \
124 	LIST_FOREACH(ia, INADDR_HASH((addr).s_addr), ia_hash) \
125 		if (IA_SIN(ia)->sin_addr.s_addr == (addr).s_addr) \
126 			break; \
127 } while (0)
128 
129 /*
130  * Macro for finding the interface (ifnet structure) corresponding to one
131  * of our IP addresses.
132  */
133 #define INADDR_TO_IFP(addr, ifp) \
134 	/* struct in_addr addr; */ \
135 	/* struct ifnet *ifp; */ \
136 { \
137 	struct in_ifaddr *ia; \
138 \
139 	INADDR_TO_IFADDR(addr, ia); \
140 	(ifp) = (ia == NULL) ? NULL : ia->ia_ifp; \
141 }
142 
143 /*
144  * Macro for finding the internet address structure (in_ifaddr) corresponding
145  * to a given interface (ifnet structure).
146  */
147 #define IFP_TO_IA(ifp, ia) \
148 	/* struct ifnet *ifp; */ \
149 	/* struct in_ifaddr *ia; */ \
150 { \
151 	for ((ia) = TAILQ_FIRST(&V_in_ifaddrhead); \
152 	    (ia) != NULL && (ia)->ia_ifp != (ifp); \
153 	    (ia) = TAILQ_NEXT((ia), ia_link)) \
154 		continue; \
155 }
156 #endif
157 
158 /*
159  * IP datagram reassembly.
160  */
161 #define	IPREASS_NHASH_LOG2	6
162 #define	IPREASS_NHASH		(1 << IPREASS_NHASH_LOG2)
163 #define	IPREASS_HMASK		(IPREASS_NHASH - 1)
164 #define	IPREASS_HASH(x,y) \
165 	(((((x) & 0xF) | ((((x) >> 8) & 0xF) << 4)) ^ (y)) & IPREASS_HMASK)
166 
167 /*
168  * Legacy IPv4 IGMP per-link structure.
169  */
170 struct router_info {
171 	struct ifnet *rti_ifp;
172 	int    rti_type; /* type of router which is querier on this interface */
173 	int    rti_time; /* # of slow timeouts since last old query */
174 	SLIST_ENTRY(router_info) rti_list;
175 };
176 
177 /*
178  * Per-interface IGMP router version information.
179  */
180 struct igmp_ifinfo {
181 	LIST_ENTRY(igmp_ifinfo) igi_link;
182 	struct ifnet *igi_ifp;	/* interface this instance belongs to */
183 	uint32_t igi_version;	/* IGMPv3 Host Compatibility Mode */
184 	uint32_t igi_v1_timer;	/* IGMPv1 Querier Present timer (s) */
185 	uint32_t igi_v2_timer;	/* IGMPv2 Querier Present timer (s) */
186 	uint32_t igi_v3_timer;	/* IGMPv3 General Query (interface) timer (s)*/
187 	uint32_t igi_flags;	/* IGMP per-interface flags */
188 	uint32_t igi_rv;	/* IGMPv3 Robustness Variable */
189 	uint32_t igi_qi;	/* IGMPv3 Query Interval (s) */
190 	uint32_t igi_qri;	/* IGMPv3 Query Response Interval (s) */
191 	uint32_t igi_uri;	/* IGMPv3 Unsolicited Report Interval (s) */
192 	SLIST_HEAD(,in_multi)	igi_relinmhead; /* released groups */
193 	struct ifqueue	 igi_gq;	/* queue of general query responses */
194 };
195 
196 #define IGIF_SILENT	0x00000001	/* Do not use IGMP on this ifp */
197 #define IGIF_LOOPBACK	0x00000002	/* Send IGMP reports to loopback */
198 
199 /*
200  * IPv4 multicast IGMP-layer source entry.
201  */
202 struct ip_msource {
203 	RB_ENTRY(ip_msource)	ims_link;	/* RB tree links */
204 	in_addr_t		ims_haddr;	/* host byte order */
205 	struct ims_st {
206 		uint16_t	ex;		/* # of exclusive members */
207 		uint16_t	in;		/* # of inclusive members */
208 	}			ims_st[2];	/* state at t0, t1 */
209 	uint8_t			ims_stp;	/* pending query */
210 };
211 
212 /*
213  * IPv4 multicast PCB-layer source entry.
214  */
215 struct in_msource {
216 	RB_ENTRY(ip_msource)	ims_link;	/* RB tree links */
217 	in_addr_t		ims_haddr;	/* host byte order */
218 	uint8_t			imsl_st[2];	/* state before/at commit */
219 };
220 
221 RB_HEAD(ip_msource_tree, ip_msource);	/* define struct ip_msource_tree */
222 
223 static __inline int
224 ip_msource_cmp(const struct ip_msource *a, const struct ip_msource *b)
225 {
226 
227 	if (a->ims_haddr < b->ims_haddr)
228 		return (-1);
229 	if (a->ims_haddr == b->ims_haddr)
230 		return (0);
231 	return (1);
232 }
233 RB_PROTOTYPE(ip_msource_tree, ip_msource, ims_link, ip_msource_cmp);
234 
235 /*
236  * IPv4 multicast PCB-layer group filter descriptor.
237  */
238 struct in_mfilter {
239 	struct ip_msource_tree	imf_sources; /* source list for (S,G) */
240 	u_long			imf_nsrc;    /* # of source entries */
241 	uint8_t			imf_st[2];   /* state before/at commit */
242 };
243 
244 /*
245  * IPv4 group descriptor.
246  *
247  * For every entry on an ifnet's if_multiaddrs list which represents
248  * an IP multicast group, there is one of these structures.
249  *
250  * If any source filters are present, then a node will exist in the RB-tree
251  * to permit fast lookup by source whenever an operation takes place.
252  * This permits pre-order traversal when we issue reports.
253  * Source filter trees are kept separately from the socket layer to
254  * greatly simplify locking.
255  *
256  * When IGMPv3 is active, inm_timer is the response to group query timer.
257  * The state-change timer inm_sctimer is separate; whenever state changes
258  * for the group the state change record is generated and transmitted,
259  * and kept if retransmissions are necessary.
260  *
261  * FUTURE: inm_link is now only used when groups are being purged
262  * on a detaching ifnet. It could be demoted to a SLIST_ENTRY, but
263  * because it is at the very start of the struct, we can't do this
264  * w/o breaking the ABI for ifmcstat.
265  */
266 struct in_multi {
267 	LIST_ENTRY(in_multi) inm_link;	/* to-be-released by in_ifdetach */
268 	struct	in_addr inm_addr;	/* IP multicast address, convenience */
269 	struct	ifnet *inm_ifp;		/* back pointer to ifnet */
270 	struct	ifmultiaddr *inm_ifma;	/* back pointer to ifmultiaddr */
271 	u_int	inm_timer;		/* IGMPv1/v2 group / v3 query timer */
272 	u_int	inm_state;		/* state of the membership */
273 	void	*inm_rti;		/* unused, legacy field */
274 	u_int	inm_refcount;		/* reference count */
275 
276 	/* New fields for IGMPv3 follow. */
277 	struct igmp_ifinfo	*inm_igi;	/* IGMP info */
278 	SLIST_ENTRY(in_multi)	 inm_nrele;	/* to-be-released by IGMP */
279 	struct ip_msource_tree	 inm_srcs;	/* tree of sources */
280 	u_long			 inm_nsrc;	/* # of tree entries */
281 
282 	struct ifqueue		 inm_scq;	/* queue of pending
283 						 * state-change packets */
284 	struct timeval		 inm_lastgsrtv;	/* Time of last G-S-R query */
285 	uint16_t		 inm_sctimer;	/* state-change timer */
286 	uint16_t		 inm_scrv;	/* state-change rexmit count */
287 
288 	/*
289 	 * SSM state counters which track state at T0 (the time the last
290 	 * state-change report's RV timer went to zero) and T1
291 	 * (time of pending report, i.e. now).
292 	 * Used for computing IGMPv3 state-change reports. Several refcounts
293 	 * are maintained here to optimize for common use-cases.
294 	 */
295 	struct inm_st {
296 		uint16_t	iss_fmode;	/* IGMP filter mode */
297 		uint16_t	iss_asm;	/* # of ASM listeners */
298 		uint16_t	iss_ex;		/* # of exclusive members */
299 		uint16_t	iss_in;		/* # of inclusive members */
300 		uint16_t	iss_rec;	/* # of recorded sources */
301 	}			inm_st[2];	/* state at t0, t1 */
302 };
303 
304 /*
305  * Helper function to derive the filter mode on a source entry
306  * from its internal counters. Predicates are:
307  *  A source is only excluded if all listeners exclude it.
308  *  A source is only included if no listeners exclude it,
309  *  and at least one listener includes it.
310  * May be used by ifmcstat(8).
311  */
312 static __inline uint8_t
313 ims_get_mode(const struct in_multi *inm, const struct ip_msource *ims,
314     uint8_t t)
315 {
316 
317 	t = !!t;
318 	if (inm->inm_st[t].iss_ex > 0 &&
319 	    inm->inm_st[t].iss_ex == ims->ims_st[t].ex)
320 		return (MCAST_EXCLUDE);
321 	else if (ims->ims_st[t].in > 0 && ims->ims_st[t].ex == 0)
322 		return (MCAST_INCLUDE);
323 	return (MCAST_UNDEFINED);
324 }
325 
326 #ifdef _KERNEL
327 
328 #ifdef SYSCTL_DECL
329 SYSCTL_DECL(_net_inet);
330 SYSCTL_DECL(_net_inet_ip);
331 SYSCTL_DECL(_net_inet_raw);
332 #endif
333 
334 LIST_HEAD(in_multihead, in_multi);	/* XXX unused */
335 #ifdef VIMAGE_GLOBALS
336 extern struct in_multihead in_multihead;
337 #endif /* BURN_BRIDGES */
338 
339 /*
340  * Lock macros for IPv4 layer multicast address lists.  IPv4 lock goes
341  * before link layer multicast locks in the lock order.  In most cases,
342  * consumers of IN_*_MULTI() macros should acquire the locks before
343  * calling them; users of the in_{add,del}multi() functions should not.
344  */
345 extern struct mtx in_multi_mtx;
346 #define	IN_MULTI_LOCK()		mtx_lock(&in_multi_mtx)
347 #define	IN_MULTI_UNLOCK()	mtx_unlock(&in_multi_mtx)
348 #define	IN_MULTI_LOCK_ASSERT()	mtx_assert(&in_multi_mtx, MA_OWNED)
349 #define	IN_MULTI_UNLOCK_ASSERT() mtx_assert(&in_multi_mtx, MA_NOTOWNED)
350 
351 /*
352  * Function for looking up an in_multi record for an IPv4 multicast address
353  * on a given interface. ifp must be valid. If no record found, return NULL.
354  * The IN_MULTI_LOCK and IF_ADDR_LOCK on ifp must be held.
355  */
356 static __inline struct in_multi *
357 inm_lookup_locked(struct ifnet *ifp, const struct in_addr ina)
358 {
359 	struct ifmultiaddr *ifma;
360 	struct in_multi *inm;
361 
362 	IN_MULTI_LOCK_ASSERT();
363 	IF_ADDR_LOCK_ASSERT(ifp);
364 
365 	inm = NULL;
366 	TAILQ_FOREACH(ifma, &((ifp)->if_multiaddrs), ifma_link) {
367 		if (ifma->ifma_addr->sa_family == AF_INET) {
368 			inm = (struct in_multi *)ifma->ifma_protospec;
369 			if (inm->inm_addr.s_addr == ina.s_addr)
370 				break;
371 			inm = NULL;
372 		}
373 	}
374 	return (inm);
375 }
376 
377 /*
378  * Wrapper for inm_lookup_locked().
379  * The IF_ADDR_LOCK will be taken on ifp and released on return.
380  */
381 static __inline struct in_multi *
382 inm_lookup(struct ifnet *ifp, const struct in_addr ina)
383 {
384 	struct in_multi *inm;
385 
386 	IN_MULTI_LOCK_ASSERT();
387 	IF_ADDR_LOCK(ifp);
388 	inm = inm_lookup_locked(ifp, ina);
389 	IF_ADDR_UNLOCK(ifp);
390 
391 	return (inm);
392 }
393 
394 /* Acquire an in_multi record. */
395 static __inline void
396 inm_acquire_locked(struct in_multi *inm)
397 {
398 
399 	IN_MULTI_LOCK_ASSERT();
400 	++inm->inm_refcount;
401 }
402 
403 /*
404  * Return values for imo_multi_filter().
405  */
406 #define MCAST_PASS		0	/* Pass */
407 #define MCAST_NOTGMEMBER	1	/* This host not a member of group */
408 #define MCAST_NOTSMEMBER	2	/* This host excluded source */
409 #define MCAST_MUTED		3	/* [deprecated] */
410 
411 struct	rtentry;
412 struct	route;
413 struct	ip_moptions;
414 
415 int	imo_multi_filter(const struct ip_moptions *, const struct ifnet *,
416 	    const struct sockaddr *, const struct sockaddr *);
417 void	inm_commit(struct in_multi *);
418 void	inm_clear_recorded(struct in_multi *);
419 void	inm_print(const struct in_multi *);
420 int	inm_record_source(struct in_multi *inm, const in_addr_t);
421 void	inm_release(struct in_multi *);
422 void	inm_release_locked(struct in_multi *);
423 struct	in_multi *
424 	in_addmulti(struct in_addr *, struct ifnet *);
425 void	in_delmulti(struct in_multi *);
426 int	in_joingroup(struct ifnet *, const struct in_addr *,
427 	    /*const*/ struct in_mfilter *, struct in_multi **);
428 int	in_joingroup_locked(struct ifnet *, const struct in_addr *,
429 	    /*const*/ struct in_mfilter *, struct in_multi **);
430 int	in_leavegroup(struct in_multi *, /*const*/ struct in_mfilter *);
431 int	in_leavegroup_locked(struct in_multi *,
432 	    /*const*/ struct in_mfilter *);
433 int	in_control(struct socket *, u_long, caddr_t, struct ifnet *,
434 	    struct thread *);
435 void	in_rtqdrain(void);
436 void	ip_input(struct mbuf *);
437 int	in_ifadown(struct ifaddr *ifa, int);
438 void	in_ifscrub(struct ifnet *, struct in_ifaddr *);
439 struct	mbuf	*ip_fastforward(struct mbuf *);
440 void	*in_domifattach(struct ifnet *);
441 void	in_domifdetach(struct ifnet *, void *);
442 
443 
444 /* XXX */
445 void	 in_rtalloc_ign(struct route *ro, u_long ignflags, u_int fibnum);
446 void	 in_rtalloc(struct route *ro, u_int fibnum);
447 struct rtentry *in_rtalloc1(struct sockaddr *, int, u_long, u_int);
448 void	 in_rtredirect(struct sockaddr *, struct sockaddr *,
449 	    struct sockaddr *, int, struct sockaddr *, u_int);
450 int	 in_rtrequest(int, struct sockaddr *,
451 	    struct sockaddr *, struct sockaddr *, int, struct rtentry **, u_int);
452 
453 #if 0
454 int	 in_rt_getifa(struct rt_addrinfo *, u_int fibnum);
455 int	 in_rtioctl(u_long, caddr_t, u_int);
456 int	 in_rtrequest1(int, struct rt_addrinfo *, struct rtentry **, u_int);
457 #endif
458 #endif /* _KERNEL */
459 
460 /* INET6 stuff */
461 #include <netinet6/in6_var.h>
462 
463 #endif /* _NETINET_IN_VAR_H_ */
464