xref: /freebsd/sys/net/route.h (revision 2a3e3873a1e4cd958f2b0f85d3b10cfa40575d30)
1 /*-
2  * Copyright (c) 1980, 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  *	@(#)route.h	8.4 (Berkeley) 1/9/95
30  * $FreeBSD$
31  */
32 
33 #ifndef _NET_ROUTE_H_
34 #define _NET_ROUTE_H_
35 
36 /*
37  * Kernel resident routing tables.
38  *
39  * The routing tables are initialized when interface addresses
40  * are set by making entries for all directly connected interfaces.
41  */
42 
43 /*
44  * A route consists of a destination address, a reference
45  * to a routing entry, and a reference to an llentry.
46  * These are often held by protocols in their control
47  * blocks, e.g. inpcb.
48  */
49 struct route {
50 	struct	rtentry *ro_rt;
51 	struct	llentry *ro_lle;
52 	struct	in_ifaddr *ro_ia;
53 	int		ro_flags;
54 	struct	sockaddr ro_dst;
55 };
56 
57 #define	RT_CACHING_CONTEXT	0x1	/* XXX: not used anywhere */
58 #define	RT_NORTREF		0x2	/* doesn't hold reference on ro_rt */
59 
60 /*
61  * These numbers are used by reliable protocols for determining
62  * retransmission behavior and are included in the routing structure.
63  */
64 struct rt_metrics_lite {
65 	u_long	rmx_mtu;	/* MTU for this path */
66 	u_long	rmx_expire;	/* lifetime for route, e.g. redirect */
67 	u_long	rmx_pksent;	/* packets sent using this route */
68 	u_long	rmx_weight;	/* absolute weight */
69 };
70 
71 struct rt_metrics {
72 	u_long	rmx_locks;	/* Kernel must leave these values alone */
73 	u_long	rmx_mtu;	/* MTU for this path */
74 	u_long	rmx_hopcount;	/* max hops expected */
75 	u_long	rmx_expire;	/* lifetime for route, e.g. redirect */
76 	u_long	rmx_recvpipe;	/* inbound delay-bandwidth product */
77 	u_long	rmx_sendpipe;	/* outbound delay-bandwidth product */
78 	u_long	rmx_ssthresh;	/* outbound gateway buffer limit */
79 	u_long	rmx_rtt;	/* estimated round trip time */
80 	u_long	rmx_rttvar;	/* estimated rtt variance */
81 	u_long	rmx_pksent;	/* packets sent using this route */
82 	u_long	rmx_weight;	/* route weight */
83 	u_long	rmx_filler[3];	/* will be used for T/TCP later */
84 };
85 
86 /*
87  * rmx_rtt and rmx_rttvar are stored as microseconds;
88  * RTTTOPRHZ(rtt) converts to a value suitable for use
89  * by a protocol slowtimo counter.
90  */
91 #define	RTM_RTTUNIT	1000000	/* units for rtt, rttvar, as units per sec */
92 #define	RTTTOPRHZ(r)	((r) / (RTM_RTTUNIT / PR_SLOWHZ))
93 
94 #define	RT_DEFAULT_FIB	0	/* Explicitly mark fib=0 restricted cases */
95 extern u_int rt_numfibs;	/* number fo usable routing tables */
96 /*
97  * XXX kernel function pointer `rt_output' is visible to applications.
98  */
99 struct mbuf;
100 
101 /*
102  * We distinguish between routes to hosts and routes to networks,
103  * preferring the former if available.  For each route we infer
104  * the interface to use from the gateway address supplied when
105  * the route was entered.  Routes that forward packets through
106  * gateways are marked so that the output routines know to address the
107  * gateway rather than the ultimate destination.
108  */
109 #ifndef RNF_NORMAL
110 #include <net/radix.h>
111 #ifdef RADIX_MPATH
112 #include <net/radix_mpath.h>
113 #endif
114 #endif
115 struct rtentry {
116 	struct	radix_node rt_nodes[2];	/* tree glue, and other values */
117 	/*
118 	 * XXX struct rtentry must begin with a struct radix_node (or two!)
119 	 * because the code does some casts of a 'struct radix_node *'
120 	 * to a 'struct rtentry *'
121 	 */
122 #define	rt_key(r)	(*((struct sockaddr **)(&(r)->rt_nodes->rn_key)))
123 #define	rt_mask(r)	(*((struct sockaddr **)(&(r)->rt_nodes->rn_mask)))
124 	struct	sockaddr *rt_gateway;	/* value */
125 	int	rt_flags;		/* up/down?, host/net */
126 	int	rt_refcnt;		/* # held references */
127 	struct	ifnet *rt_ifp;		/* the answer: interface to use */
128 	struct	ifaddr *rt_ifa;		/* the answer: interface address to use */
129 	struct	rt_metrics_lite rt_rmx;	/* metrics used by rx'ing protocols */
130 	u_int	rt_fibnum;		/* which FIB */
131 #ifdef _KERNEL
132 	/* XXX ugly, user apps use this definition but don't have a mtx def */
133 	struct	mtx rt_mtx;		/* mutex for routing entry */
134 #endif
135 };
136 
137 /*
138  * Following structure necessary for 4.3 compatibility;
139  * We should eventually move it to a compat file.
140  */
141 struct ortentry {
142 	u_long	rt_hash;		/* to speed lookups */
143 	struct	sockaddr rt_dst;	/* key */
144 	struct	sockaddr rt_gateway;	/* value */
145 	short	rt_flags;		/* up/down?, host/net */
146 	short	rt_refcnt;		/* # held references */
147 	u_long	rt_use;			/* raw # packets forwarded */
148 	struct	ifnet *rt_ifp;		/* the answer: interface to use */
149 };
150 
151 #define rt_use rt_rmx.rmx_pksent
152 
153 #define	RTF_UP		0x1		/* route usable */
154 #define	RTF_GATEWAY	0x2		/* destination is a gateway */
155 #define	RTF_HOST	0x4		/* host entry (net otherwise) */
156 #define	RTF_REJECT	0x8		/* host or net unreachable */
157 #define	RTF_DYNAMIC	0x10		/* created dynamically (by redirect) */
158 #define	RTF_MODIFIED	0x20		/* modified dynamically (by redirect) */
159 #define RTF_DONE	0x40		/* message confirmed */
160 /*			0x80		   unused, was RTF_DELCLONE */
161 /*			0x100		   unused, was RTF_CLONING */
162 #define RTF_XRESOLVE	0x200		/* external daemon resolves name */
163 #define RTF_LLINFO	0x400		/* DEPRECATED - exists ONLY for backward
164 					   compatibility */
165 #define RTF_LLDATA	0x400		/* used by apps to add/del L2 entries */
166 #define RTF_STATIC	0x800		/* manually added */
167 #define RTF_BLACKHOLE	0x1000		/* just discard pkts (during updates) */
168 #define RTF_PROTO2	0x4000		/* protocol specific routing flag */
169 #define RTF_PROTO1	0x8000		/* protocol specific routing flag */
170 
171 /* XXX: temporary to stay API/ABI compatible with userland */
172 #ifndef _KERNEL
173 #define RTF_PRCLONING	0x10000		/* unused, for compatibility */
174 #endif
175 
176 /*			0x20000		   unused, was RTF_WASCLONED */
177 #define RTF_PROTO3	0x40000		/* protocol specific routing flag */
178 /*			0x80000		   unused */
179 #define RTF_PINNED	0x100000	/* route is immutable */
180 #define	RTF_LOCAL	0x200000 	/* route represents a local address */
181 #define	RTF_BROADCAST	0x400000	/* route represents a bcast address */
182 #define	RTF_MULTICAST	0x800000	/* route represents a mcast address */
183 					/* 0x8000000 and up unassigned */
184 #define	RTF_STICKY	 0x10000000	/* always route dst->src */
185 
186 #define	RTF_RNH_LOCKED	 0x40000000	/* radix node head is locked */
187 
188 /* Mask of RTF flags that are allowed to be modified by RTM_CHANGE. */
189 #define RTF_FMASK	\
190 	(RTF_PROTO1 | RTF_PROTO2 | RTF_PROTO3 | RTF_BLACKHOLE | \
191 	 RTF_REJECT | RTF_STATIC | RTF_STICKY)
192 
193 /*
194  * Routing statistics.
195  */
196 struct	rtstat {
197 	short	rts_badredirect;	/* bogus redirect calls */
198 	short	rts_dynamic;		/* routes created by redirects */
199 	short	rts_newgateway;		/* routes modified by redirects */
200 	short	rts_unreach;		/* lookups which failed */
201 	short	rts_wildcard;		/* lookups satisfied by a wildcard */
202 };
203 /*
204  * Structures for routing messages.
205  */
206 struct rt_msghdr {
207 	u_short	rtm_msglen;	/* to skip over non-understood messages */
208 	u_char	rtm_version;	/* future binary compatibility */
209 	u_char	rtm_type;	/* message type */
210 	u_short	rtm_index;	/* index for associated ifp */
211 	int	rtm_flags;	/* flags, incl. kern & message, e.g. DONE */
212 	int	rtm_addrs;	/* bitmask identifying sockaddrs in msg */
213 	pid_t	rtm_pid;	/* identify sender */
214 	int	rtm_seq;	/* for sender to identify action */
215 	int	rtm_errno;	/* why failed */
216 	int	rtm_fmask;	/* bitmask used in RTM_CHANGE message */
217 	u_long	rtm_inits;	/* which metrics we are initializing */
218 	struct	rt_metrics rtm_rmx; /* metrics themselves */
219 };
220 
221 #define RTM_VERSION	5	/* Up the ante and ignore older versions */
222 
223 /*
224  * Message types.
225  */
226 #define RTM_ADD		0x1	/* Add Route */
227 #define RTM_DELETE	0x2	/* Delete Route */
228 #define RTM_CHANGE	0x3	/* Change Metrics or flags */
229 #define RTM_GET		0x4	/* Report Metrics */
230 #define RTM_LOSING	0x5	/* Kernel Suspects Partitioning */
231 #define RTM_REDIRECT	0x6	/* Told to use different route */
232 #define RTM_MISS	0x7	/* Lookup failed on this address */
233 #define RTM_LOCK	0x8	/* fix specified metrics */
234 #define RTM_OLDADD	0x9	/* caused by SIOCADDRT */
235 #define RTM_OLDDEL	0xa	/* caused by SIOCDELRT */
236 #define RTM_RESOLVE	0xb	/* req to resolve dst to LL addr */
237 #define RTM_NEWADDR	0xc	/* address being added to iface */
238 #define RTM_DELADDR	0xd	/* address being removed from iface */
239 #define RTM_IFINFO	0xe	/* iface going up/down etc. */
240 #define	RTM_NEWMADDR	0xf	/* mcast group membership being added to if */
241 #define	RTM_DELMADDR	0x10	/* mcast group membership being deleted */
242 #define	RTM_IFANNOUNCE	0x11	/* iface arrival/departure */
243 #define	RTM_IEEE80211	0x12	/* IEEE80211 wireless event */
244 
245 /*
246  * Bitmask values for rtm_inits and rmx_locks.
247  */
248 #define RTV_MTU		0x1	/* init or lock _mtu */
249 #define RTV_HOPCOUNT	0x2	/* init or lock _hopcount */
250 #define RTV_EXPIRE	0x4	/* init or lock _expire */
251 #define RTV_RPIPE	0x8	/* init or lock _recvpipe */
252 #define RTV_SPIPE	0x10	/* init or lock _sendpipe */
253 #define RTV_SSTHRESH	0x20	/* init or lock _ssthresh */
254 #define RTV_RTT		0x40	/* init or lock _rtt */
255 #define RTV_RTTVAR	0x80	/* init or lock _rttvar */
256 #define RTV_WEIGHT	0x100	/* init or lock _weight */
257 
258 /*
259  * Bitmask values for rtm_addrs.
260  */
261 #define RTA_DST		0x1	/* destination sockaddr present */
262 #define RTA_GATEWAY	0x2	/* gateway sockaddr present */
263 #define RTA_NETMASK	0x4	/* netmask sockaddr present */
264 #define RTA_GENMASK	0x8	/* cloning mask sockaddr present */
265 #define RTA_IFP		0x10	/* interface name sockaddr present */
266 #define RTA_IFA		0x20	/* interface addr sockaddr present */
267 #define RTA_AUTHOR	0x40	/* sockaddr for author of redirect */
268 #define RTA_BRD		0x80	/* for NEWADDR, broadcast or p-p dest addr */
269 
270 /*
271  * Index offsets for sockaddr array for alternate internal encoding.
272  */
273 #define RTAX_DST	0	/* destination sockaddr present */
274 #define RTAX_GATEWAY	1	/* gateway sockaddr present */
275 #define RTAX_NETMASK	2	/* netmask sockaddr present */
276 #define RTAX_GENMASK	3	/* cloning mask sockaddr present */
277 #define RTAX_IFP	4	/* interface name sockaddr present */
278 #define RTAX_IFA	5	/* interface addr sockaddr present */
279 #define RTAX_AUTHOR	6	/* sockaddr for author of redirect */
280 #define RTAX_BRD	7	/* for NEWADDR, broadcast or p-p dest addr */
281 #define RTAX_MAX	8	/* size of array to allocate */
282 
283 struct rt_addrinfo {
284 	int	rti_addrs;
285 	struct	sockaddr *rti_info[RTAX_MAX];
286 	int	rti_flags;
287 	struct	ifaddr *rti_ifa;
288 	struct	ifnet *rti_ifp;
289 };
290 
291 /*
292  * This macro returns the size of a struct sockaddr when passed
293  * through a routing socket. Basically we round up sa_len to
294  * a multiple of sizeof(long), with a minimum of sizeof(long).
295  * The check for a NULL pointer is just a convenience, probably never used.
296  * The case sa_len == 0 should only apply to empty structures.
297  */
298 #define SA_SIZE(sa)						\
299     (  (!(sa) || ((struct sockaddr *)(sa))->sa_len == 0) ?	\
300 	sizeof(long)		:				\
301 	1 + ( (((struct sockaddr *)(sa))->sa_len - 1) | (sizeof(long) - 1) ) )
302 
303 #ifdef _KERNEL
304 
305 #define RT_LINK_IS_UP(ifp)	(!((ifp)->if_capabilities & IFCAP_LINKSTATE) \
306 				 || (ifp)->if_link_state == LINK_STATE_UP)
307 
308 #define	RT_LOCK_INIT(_rt) \
309 	mtx_init(&(_rt)->rt_mtx, "rtentry", NULL, MTX_DEF | MTX_DUPOK)
310 #define	RT_LOCK(_rt)		mtx_lock(&(_rt)->rt_mtx)
311 #define	RT_UNLOCK(_rt)		mtx_unlock(&(_rt)->rt_mtx)
312 #define	RT_LOCK_DESTROY(_rt)	mtx_destroy(&(_rt)->rt_mtx)
313 #define	RT_LOCK_ASSERT(_rt)	mtx_assert(&(_rt)->rt_mtx, MA_OWNED)
314 
315 #define	RT_ADDREF(_rt)	do {					\
316 	RT_LOCK_ASSERT(_rt);					\
317 	KASSERT((_rt)->rt_refcnt >= 0,				\
318 		("negative refcnt %d", (_rt)->rt_refcnt));	\
319 	(_rt)->rt_refcnt++;					\
320 } while (0)
321 
322 #define	RT_REMREF(_rt)	do {					\
323 	RT_LOCK_ASSERT(_rt);					\
324 	KASSERT((_rt)->rt_refcnt > 0,				\
325 		("bogus refcnt %d", (_rt)->rt_refcnt));	\
326 	(_rt)->rt_refcnt--;					\
327 } while (0)
328 
329 #define	RTFREE_LOCKED(_rt) do {					\
330 	if ((_rt)->rt_refcnt <= 1)				\
331 		rtfree(_rt);					\
332 	else {							\
333 		RT_REMREF(_rt);					\
334 		RT_UNLOCK(_rt);					\
335 	}							\
336 	/* guard against invalid refs */			\
337 	_rt = 0;						\
338 } while (0)
339 
340 #define	RTFREE(_rt) do {					\
341 	RT_LOCK(_rt);						\
342 	RTFREE_LOCKED(_rt);					\
343 } while (0)
344 
345 #define	RO_RTFREE(_ro) do {					\
346 	if ((_ro)->ro_rt) {					\
347 		if ((_ro)->ro_flags & RT_NORTREF) {		\
348 			(_ro)->ro_flags &= ~RT_NORTREF;		\
349 			(_ro)->ro_rt = NULL;			\
350 		} else {					\
351 			RT_LOCK((_ro)->ro_rt);			\
352 			RTFREE_LOCKED((_ro)->ro_rt);		\
353 		}						\
354 	}							\
355 } while (0)
356 
357 struct radix_node_head *rt_tables_get_rnh(int, int);
358 
359 struct ifmultiaddr;
360 
361 void	 rt_ieee80211msg(struct ifnet *, int, void *, size_t);
362 void	 rt_ifannouncemsg(struct ifnet *, int);
363 void	 rt_ifmsg(struct ifnet *);
364 void	 rt_missmsg(int, struct rt_addrinfo *, int, int);
365 void	 rt_missmsg_fib(int, struct rt_addrinfo *, int, int, int);
366 void	 rt_newaddrmsg(int, struct ifaddr *, int, struct rtentry *);
367 void	 rt_newaddrmsg_fib(int, struct ifaddr *, int, struct rtentry *, int);
368 void	 rt_newmaddrmsg(int, struct ifmultiaddr *);
369 int	 rt_setgate(struct rtentry *, struct sockaddr *, struct sockaddr *);
370 void 	 rt_maskedcopy(struct sockaddr *, struct sockaddr *, struct sockaddr *);
371 
372 /*
373  * Note the following locking behavior:
374  *
375  *    rtalloc_ign() and rtalloc() return ro->ro_rt unlocked
376  *
377  *    rtalloc1() returns a locked rtentry
378  *
379  *    rtfree() and RTFREE_LOCKED() require a locked rtentry
380  *
381  *    RTFREE() uses an unlocked entry.
382  */
383 
384 int	 rtexpunge(struct rtentry *);
385 void	 rtfree(struct rtentry *);
386 int	 rt_check(struct rtentry **, struct rtentry **, struct sockaddr *);
387 
388 /* XXX MRT COMPAT VERSIONS THAT SET UNIVERSE to 0 */
389 /* Thes are used by old code not yet converted to use multiple FIBS */
390 int	 rt_getifa(struct rt_addrinfo *);
391 void	 rtalloc_ign(struct route *ro, u_long ignflags);
392 void	 rtalloc(struct route *ro); /* XXX deprecated, use rtalloc_ign(ro, 0) */
393 struct rtentry *rtalloc1(struct sockaddr *, int, u_long);
394 int	 rtinit(struct ifaddr *, int, int);
395 int	 rtioctl(u_long, caddr_t);
396 void	 rtredirect(struct sockaddr *, struct sockaddr *,
397 	    struct sockaddr *, int, struct sockaddr *);
398 int	 rtrequest(int, struct sockaddr *,
399 	    struct sockaddr *, struct sockaddr *, int, struct rtentry **);
400 
401 #ifndef BURN_BRIDGES
402 /* defaults to "all" FIBs */
403 int	 rtinit_fib(struct ifaddr *, int, int);
404 #endif
405 
406 /* XXX MRT NEW VERSIONS THAT USE FIBs
407  * For now the protocol indepedent versions are the same as the AF_INET ones
408  * but this will change..
409  */
410 int	 rt_getifa_fib(struct rt_addrinfo *, u_int fibnum);
411 void	 rtalloc_ign_fib(struct route *ro, u_long ignflags, u_int fibnum);
412 void	 rtalloc_fib(struct route *ro, u_int fibnum);
413 struct rtentry *rtalloc1_fib(struct sockaddr *, int, u_long, u_int);
414 int	 rtioctl_fib(u_long, caddr_t, u_int);
415 void	 rtredirect_fib(struct sockaddr *, struct sockaddr *,
416 	    struct sockaddr *, int, struct sockaddr *, u_int);
417 int	 rtrequest_fib(int, struct sockaddr *,
418 	    struct sockaddr *, struct sockaddr *, int, struct rtentry **, u_int);
419 int	 rtrequest1_fib(int, struct rt_addrinfo *, struct rtentry **, u_int);
420 
421 #include <sys/eventhandler.h>
422 typedef void (*rtevent_arp_update_fn)(void *, struct rtentry *, uint8_t *, struct sockaddr *);
423 typedef void (*rtevent_redirect_fn)(void *, struct rtentry *, struct rtentry *, struct sockaddr *);
424 /* route_arp_update_event is no longer generated; see arp_update_event */
425 EVENTHANDLER_DECLARE(route_arp_update_event, rtevent_arp_update_fn);
426 EVENTHANDLER_DECLARE(route_redirect_event, rtevent_redirect_fn);
427 #endif
428 
429 #endif
430