xref: /freebsd/sys/net/route.h (revision 66e576525d35c68fcb86f142ebaa5a448555c0c7)
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	sockaddr ro_dst;
53 };
54 
55 /*
56  * These numbers are used by reliable protocols for determining
57  * retransmission behavior and are included in the routing structure.
58  */
59 struct rt_metrics_lite {
60 	u_long	rmx_mtu;	/* MTU for this path */
61 	u_long	rmx_expire;	/* lifetime for route, e.g. redirect */
62 	u_long	rmx_pksent;	/* packets sent using this route */
63 	u_long	rmx_weight;	/* absolute weight */
64 };
65 
66 struct rt_metrics {
67 	u_long	rmx_locks;	/* Kernel must leave these values alone */
68 	u_long	rmx_mtu;	/* MTU for this path */
69 	u_long	rmx_hopcount;	/* max hops expected */
70 	u_long	rmx_expire;	/* lifetime for route, e.g. redirect */
71 	u_long	rmx_recvpipe;	/* inbound delay-bandwidth product */
72 	u_long	rmx_sendpipe;	/* outbound delay-bandwidth product */
73 	u_long	rmx_ssthresh;	/* outbound gateway buffer limit */
74 	u_long	rmx_rtt;	/* estimated round trip time */
75 	u_long	rmx_rttvar;	/* estimated rtt variance */
76 	u_long	rmx_pksent;	/* packets sent using this route */
77 	u_long	rmx_weight;	/* route weight */
78 	u_long	rmx_filler[3];	/* will be used for T/TCP later */
79 };
80 
81 /*
82  * rmx_rtt and rmx_rttvar are stored as microseconds;
83  * RTTTOPRHZ(rtt) converts to a value suitable for use
84  * by a protocol slowtimo counter.
85  */
86 #define	RTM_RTTUNIT	1000000	/* units for rtt, rttvar, as units per sec */
87 #define	RTTTOPRHZ(r)	((r) / (RTM_RTTUNIT / PR_SLOWHZ))
88 
89 /* MRT compile-time constants */
90 #ifdef _KERNEL
91  #ifndef ROUTETABLES
92   #define RT_NUMFIBS 1
93   #define RT_MAXFIBS 1
94  #else
95   /* while we use 4 bits in the mbuf flags, we are limited to 16 */
96   #define RT_MAXFIBS 16
97   #if ROUTETABLES > RT_MAXFIBS
98    #define RT_NUMFIBS RT_MAXFIBS
99    #error "ROUTETABLES defined too big"
100   #else
101    #if ROUTETABLES == 0
102     #define RT_NUMFIBS 1
103    #else
104     #define RT_NUMFIBS ROUTETABLES
105    #endif
106   #endif
107  #endif
108 #endif
109 
110 extern u_int rt_numfibs;	/* number fo usable routing tables */
111 extern u_int tunnel_fib;	/* tunnels use these */
112 extern u_int fwd_fib;		/* packets being forwarded use these routes */
113 /*
114  * XXX kernel function pointer `rt_output' is visible to applications.
115  */
116 struct mbuf;
117 
118 /*
119  * We distinguish between routes to hosts and routes to networks,
120  * preferring the former if available.  For each route we infer
121  * the interface to use from the gateway address supplied when
122  * the route was entered.  Routes that forward packets through
123  * gateways are marked so that the output routines know to address the
124  * gateway rather than the ultimate destination.
125  */
126 #ifndef RNF_NORMAL
127 #include <net/radix.h>
128 #ifdef RADIX_MPATH
129 #include <net/radix_mpath.h>
130 #endif
131 #endif
132 struct rtentry {
133 	struct	radix_node rt_nodes[2];	/* tree glue, and other values */
134 	/*
135 	 * XXX struct rtentry must begin with a struct radix_node (or two!)
136 	 * because the code does some casts of a 'struct radix_node *'
137 	 * to a 'struct rtentry *'
138 	 */
139 #define	rt_key(r)	(*((struct sockaddr **)(&(r)->rt_nodes->rn_key)))
140 #define	rt_mask(r)	(*((struct sockaddr **)(&(r)->rt_nodes->rn_mask)))
141 	struct	sockaddr *rt_gateway;	/* value */
142 	int	rt_flags;		/* up/down?, host/net */
143 	int	rt_refcnt;		/* # held references */
144 	struct	ifnet *rt_ifp;		/* the answer: interface to use */
145 	struct	ifaddr *rt_ifa;		/* the answer: interface address to use */
146 	struct	rt_metrics_lite rt_rmx;	/* metrics used by rx'ing protocols */
147 	u_int	rt_fibnum;		/* which FIB */
148 #ifdef _KERNEL
149 	/* XXX ugly, user apps use this definition but don't have a mtx def */
150 	struct	mtx rt_mtx;		/* mutex for routing entry */
151 #endif
152 };
153 
154 /*
155  * Following structure necessary for 4.3 compatibility;
156  * We should eventually move it to a compat file.
157  */
158 struct ortentry {
159 	u_long	rt_hash;		/* to speed lookups */
160 	struct	sockaddr rt_dst;	/* key */
161 	struct	sockaddr rt_gateway;	/* value */
162 	short	rt_flags;		/* up/down?, host/net */
163 	short	rt_refcnt;		/* # held references */
164 	u_long	rt_use;			/* raw # packets forwarded */
165 	struct	ifnet *rt_ifp;		/* the answer: interface to use */
166 };
167 
168 #define rt_use rt_rmx.rmx_pksent
169 
170 #define	RTF_UP		0x1		/* route usable */
171 #define	RTF_GATEWAY	0x2		/* destination is a gateway */
172 #define	RTF_HOST	0x4		/* host entry (net otherwise) */
173 #define	RTF_REJECT	0x8		/* host or net unreachable */
174 #define	RTF_DYNAMIC	0x10		/* created dynamically (by redirect) */
175 #define	RTF_MODIFIED	0x20		/* modified dynamically (by redirect) */
176 #define RTF_DONE	0x40		/* message confirmed */
177 /*			0x80		   unused, was RTF_DELCLONE */
178 /*			0x100		   unused, was RTF_CLONING */
179 #define RTF_XRESOLVE	0x200		/* external daemon resolves name */
180 #define RTF_LLINFO	0x400		/* DEPRECATED - exists ONLY for backward
181 					   compatibility */
182 #define RTF_LLDATA	0x400		/* used by apps to add/del L2 entries */
183 #define RTF_STATIC	0x800		/* manually added */
184 #define RTF_BLACKHOLE	0x1000		/* just discard pkts (during updates) */
185 #define RTF_PROTO2	0x4000		/* protocol specific routing flag */
186 #define RTF_PROTO1	0x8000		/* protocol specific routing flag */
187 
188 /* XXX: temporary to stay API/ABI compatible with userland */
189 #ifndef _KERNEL
190 #define RTF_PRCLONING	0x10000		/* unused, for compatibility */
191 #endif
192 
193 /*			0x20000		   unused, was RTF_WASCLONED */
194 #define RTF_PROTO3	0x40000		/* protocol specific routing flag */
195 /*			0x80000		   unused */
196 #define RTF_PINNED	0x100000	/* future use */
197 #define	RTF_LOCAL	0x200000 	/* route represents a local address */
198 #define	RTF_BROADCAST	0x400000	/* route represents a bcast address */
199 #define	RTF_MULTICAST	0x800000	/* route represents a mcast address */
200 					/* 0x8000000 and up unassigned */
201 #define	RTF_STICKY	 0x10000000	/* always route dst->src */
202 
203 #define	RTF_RNH_LOCKED	 0x40000000	/* radix node head is locked */
204 
205 /* Mask of RTF flags that are allowed to be modified by RTM_CHANGE. */
206 #define RTF_FMASK	\
207 	(RTF_PROTO1 | RTF_PROTO2 | RTF_PROTO3 | RTF_BLACKHOLE | \
208 	 RTF_REJECT | RTF_STATIC | RTF_STICKY)
209 
210 /*
211  * Routing statistics.
212  */
213 struct	rtstat {
214 	short	rts_badredirect;	/* bogus redirect calls */
215 	short	rts_dynamic;		/* routes created by redirects */
216 	short	rts_newgateway;		/* routes modified by redirects */
217 	short	rts_unreach;		/* lookups which failed */
218 	short	rts_wildcard;		/* lookups satisfied by a wildcard */
219 };
220 /*
221  * Structures for routing messages.
222  */
223 struct rt_msghdr {
224 	u_short	rtm_msglen;	/* to skip over non-understood messages */
225 	u_char	rtm_version;	/* future binary compatibility */
226 	u_char	rtm_type;	/* message type */
227 	u_short	rtm_index;	/* index for associated ifp */
228 	int	rtm_flags;	/* flags, incl. kern & message, e.g. DONE */
229 	int	rtm_addrs;	/* bitmask identifying sockaddrs in msg */
230 	pid_t	rtm_pid;	/* identify sender */
231 	int	rtm_seq;	/* for sender to identify action */
232 	int	rtm_errno;	/* why failed */
233 	int	rtm_fmask;	/* bitmask used in RTM_CHANGE message */
234 	u_long	rtm_inits;	/* which metrics we are initializing */
235 	struct	rt_metrics rtm_rmx; /* metrics themselves */
236 };
237 
238 #define RTM_VERSION	5	/* Up the ante and ignore older versions */
239 
240 /*
241  * Message types.
242  */
243 #define RTM_ADD		0x1	/* Add Route */
244 #define RTM_DELETE	0x2	/* Delete Route */
245 #define RTM_CHANGE	0x3	/* Change Metrics or flags */
246 #define RTM_GET		0x4	/* Report Metrics */
247 #define RTM_LOSING	0x5	/* Kernel Suspects Partitioning */
248 #define RTM_REDIRECT	0x6	/* Told to use different route */
249 #define RTM_MISS	0x7	/* Lookup failed on this address */
250 #define RTM_LOCK	0x8	/* fix specified metrics */
251 #define RTM_OLDADD	0x9	/* caused by SIOCADDRT */
252 #define RTM_OLDDEL	0xa	/* caused by SIOCDELRT */
253 #define RTM_RESOLVE	0xb	/* req to resolve dst to LL addr */
254 #define RTM_NEWADDR	0xc	/* address being added to iface */
255 #define RTM_DELADDR	0xd	/* address being removed from iface */
256 #define RTM_IFINFO	0xe	/* iface going up/down etc. */
257 #define	RTM_NEWMADDR	0xf	/* mcast group membership being added to if */
258 #define	RTM_DELMADDR	0x10	/* mcast group membership being deleted */
259 #define	RTM_IFANNOUNCE	0x11	/* iface arrival/departure */
260 #define	RTM_IEEE80211	0x12	/* IEEE80211 wireless event */
261 
262 /*
263  * Bitmask values for rtm_inits and rmx_locks.
264  */
265 #define RTV_MTU		0x1	/* init or lock _mtu */
266 #define RTV_HOPCOUNT	0x2	/* init or lock _hopcount */
267 #define RTV_EXPIRE	0x4	/* init or lock _expire */
268 #define RTV_RPIPE	0x8	/* init or lock _recvpipe */
269 #define RTV_SPIPE	0x10	/* init or lock _sendpipe */
270 #define RTV_SSTHRESH	0x20	/* init or lock _ssthresh */
271 #define RTV_RTT		0x40	/* init or lock _rtt */
272 #define RTV_RTTVAR	0x80	/* init or lock _rttvar */
273 #define RTV_WEIGHT	0x100	/* init or lock _weight */
274 
275 /*
276  * Bitmask values for rtm_addrs.
277  */
278 #define RTA_DST		0x1	/* destination sockaddr present */
279 #define RTA_GATEWAY	0x2	/* gateway sockaddr present */
280 #define RTA_NETMASK	0x4	/* netmask sockaddr present */
281 #define RTA_GENMASK	0x8	/* cloning mask sockaddr present */
282 #define RTA_IFP		0x10	/* interface name sockaddr present */
283 #define RTA_IFA		0x20	/* interface addr sockaddr present */
284 #define RTA_AUTHOR	0x40	/* sockaddr for author of redirect */
285 #define RTA_BRD		0x80	/* for NEWADDR, broadcast or p-p dest addr */
286 
287 /*
288  * Index offsets for sockaddr array for alternate internal encoding.
289  */
290 #define RTAX_DST	0	/* destination sockaddr present */
291 #define RTAX_GATEWAY	1	/* gateway sockaddr present */
292 #define RTAX_NETMASK	2	/* netmask sockaddr present */
293 #define RTAX_GENMASK	3	/* cloning mask sockaddr present */
294 #define RTAX_IFP	4	/* interface name sockaddr present */
295 #define RTAX_IFA	5	/* interface addr sockaddr present */
296 #define RTAX_AUTHOR	6	/* sockaddr for author of redirect */
297 #define RTAX_BRD	7	/* for NEWADDR, broadcast or p-p dest addr */
298 #define RTAX_MAX	8	/* size of array to allocate */
299 
300 struct rt_addrinfo {
301 	int	rti_addrs;
302 	struct	sockaddr *rti_info[RTAX_MAX];
303 	int	rti_flags;
304 	struct	ifaddr *rti_ifa;
305 	struct	ifnet *rti_ifp;
306 };
307 
308 /*
309  * This macro returns the size of a struct sockaddr when passed
310  * through a routing socket. Basically we round up sa_len to
311  * a multiple of sizeof(long), with a minimum of sizeof(long).
312  * The check for a NULL pointer is just a convenience, probably never used.
313  * The case sa_len == 0 should only apply to empty structures.
314  */
315 #define SA_SIZE(sa)						\
316     (  (!(sa) || ((struct sockaddr *)(sa))->sa_len == 0) ?	\
317 	sizeof(long)		:				\
318 	1 + ( (((struct sockaddr *)(sa))->sa_len - 1) | (sizeof(long) - 1) ) )
319 
320 #ifdef _KERNEL
321 
322 #define RT_LINK_IS_UP(ifp)	(!((ifp)->if_capabilities & IFCAP_LINKSTATE) \
323 				 || (ifp)->if_link_state == LINK_STATE_UP)
324 
325 #define	RT_LOCK_INIT(_rt) \
326 	mtx_init(&(_rt)->rt_mtx, "rtentry", NULL, MTX_DEF | MTX_DUPOK)
327 #define	RT_LOCK(_rt)		mtx_lock(&(_rt)->rt_mtx)
328 #define	RT_TRYLOCK(_rt)		mtx_trylock(&(_rt)->rt_mtx)
329 #define	RT_UNLOCK(_rt)		mtx_unlock(&(_rt)->rt_mtx)
330 #define	RT_LOCK_DESTROY(_rt)	mtx_destroy(&(_rt)->rt_mtx)
331 #define	RT_LOCK_ASSERT(_rt)	mtx_assert(&(_rt)->rt_mtx, MA_OWNED)
332 
333 #define	RT_ADDREF(_rt)	do {					\
334 	RT_LOCK_ASSERT(_rt);					\
335 	KASSERT((_rt)->rt_refcnt >= 0,				\
336 		("negative refcnt %d", (_rt)->rt_refcnt));	\
337 	(_rt)->rt_refcnt++;					\
338 } while (0)
339 
340 #define	RT_REMREF(_rt)	do {					\
341 	RT_LOCK_ASSERT(_rt);					\
342 	KASSERT((_rt)->rt_refcnt > 0,				\
343 		("bogus refcnt %d", (_rt)->rt_refcnt));	\
344 	(_rt)->rt_refcnt--;					\
345 } while (0)
346 
347 #define	RTFREE_LOCKED(_rt) do {					\
348 	if ((_rt)->rt_refcnt <= 1)				\
349 		rtfree(_rt);					\
350 	else {							\
351 		RT_REMREF(_rt);					\
352 		RT_UNLOCK(_rt);					\
353 	}							\
354 	/* guard against invalid refs */			\
355 	_rt = 0;						\
356 } while (0)
357 
358 #define	RTFREE(_rt) do {					\
359 	RT_LOCK(_rt);						\
360 	RTFREE_LOCKED(_rt);					\
361 } while (0)
362 
363 #define RT_TEMP_UNLOCK(_rt) do {				\
364 	RT_ADDREF(_rt);						\
365 	RT_UNLOCK(_rt);						\
366 } while (0)
367 
368 #define RT_RELOCK(_rt) do {					\
369 	RT_LOCK(_rt);						\
370 	if ((_rt)->rt_refcnt <= 1) {				\
371 		rtfree(_rt);					\
372 		_rt = 0; /*  signal that it went away */	\
373 	} else {						\
374 		RT_REMREF(_rt);					\
375 		/* note that _rt is still valid */		\
376 	}							\
377 } while (0)
378 
379 struct radix_node_head *rt_tables_get_rnh(int, int);
380 
381 struct ifmultiaddr;
382 
383 void	 rt_ieee80211msg(struct ifnet *, int, void *, size_t);
384 void	 rt_ifannouncemsg(struct ifnet *, int);
385 void	 rt_ifmsg(struct ifnet *);
386 void	 rt_missmsg(int, struct rt_addrinfo *, int, int);
387 void	 rt_newaddrmsg(int, struct ifaddr *, int, struct rtentry *);
388 void	 rt_newmaddrmsg(int, struct ifmultiaddr *);
389 int	 rt_setgate(struct rtentry *, struct sockaddr *, struct sockaddr *);
390 void 	 rt_maskedcopy(struct sockaddr *, struct sockaddr *, struct sockaddr *);
391 
392 /*
393  * Note the following locking behavior:
394  *
395  *    rtalloc_ign() and rtalloc() return ro->ro_rt unlocked
396  *
397  *    rtalloc1() returns a locked rtentry
398  *
399  *    rtfree() and RTFREE_LOCKED() require a locked rtentry
400  *
401  *    RTFREE() uses an unlocked entry.
402  */
403 
404 int	 rtexpunge(struct rtentry *);
405 void	 rtfree(struct rtentry *);
406 int	 rt_check(struct rtentry **, struct rtentry **, struct sockaddr *);
407 
408 /* XXX MRT COMPAT VERSIONS THAT SET UNIVERSE to 0 */
409 /* Thes are used by old code not yet converted to use multiple FIBS */
410 int	 rt_getifa(struct rt_addrinfo *);
411 void	 rtalloc_ign(struct route *ro, u_long ignflags);
412 void	 rtalloc(struct route *ro); /* XXX deprecated, use rtalloc_ign(ro, 0) */
413 struct rtentry *rtalloc1(struct sockaddr *, int, u_long);
414 int	 rtinit(struct ifaddr *, int, int);
415 int	 rtioctl(u_long, caddr_t);
416 void	 rtredirect(struct sockaddr *, struct sockaddr *,
417 	    struct sockaddr *, int, struct sockaddr *);
418 int	 rtrequest(int, struct sockaddr *,
419 	    struct sockaddr *, struct sockaddr *, int, struct rtentry **);
420 
421 /* defaults to "all" FIBs */
422 int	 rtinit_fib(struct ifaddr *, int, int);
423 
424 /* XXX MRT NEW VERSIONS THAT USE FIBs
425  * For now the protocol indepedent versions are the same as the AF_INET ones
426  * but this will change..
427  */
428 int	 rt_getifa_fib(struct rt_addrinfo *, u_int fibnum);
429 void	 rtalloc_ign_fib(struct route *ro, u_long ignflags, u_int fibnum);
430 void	 rtalloc_fib(struct route *ro, u_int fibnum);
431 struct rtentry *rtalloc1_fib(struct sockaddr *, int, u_long, u_int);
432 int	 rtioctl_fib(u_long, caddr_t, u_int);
433 void	 rtredirect_fib(struct sockaddr *, struct sockaddr *,
434 	    struct sockaddr *, int, struct sockaddr *, u_int);
435 int	 rtrequest_fib(int, struct sockaddr *,
436 	    struct sockaddr *, struct sockaddr *, int, struct rtentry **, u_int);
437 int	 rtrequest1_fib(int, struct rt_addrinfo *, struct rtentry **, u_int);
438 
439 #include <sys/eventhandler.h>
440 typedef void (*rtevent_arp_update_fn)(void *, struct rtentry *, uint8_t *, struct sockaddr *);
441 typedef void (*rtevent_redirect_fn)(void *, struct rtentry *, struct rtentry *, struct sockaddr *);
442 /* route_arp_update_event is no longer generated; see arp_update_event */
443 EVENTHANDLER_DECLARE(route_arp_update_event, rtevent_arp_update_fn);
444 EVENTHANDLER_DECLARE(route_redirect_event, rtevent_redirect_fn);
445 #endif
446 
447 #endif
448