1 /*	$NetBSD: route.h,v 1.101 2016/04/28 00:16:56 ozaki-r Exp $	*/
2 
3 /*
4  * Copyright (c) 1980, 1986, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  *
31  *	@(#)route.h	8.5 (Berkeley) 2/8/95
32  */
33 
34 #ifndef _NET_ROUTE_H_
35 #define _NET_ROUTE_H_
36 
37 #include <sys/queue.h>
38 #include <sys/socket.h>
39 #include <sys/types.h>
40 #include <net/if.h>
41 
42 #if !(defined(_KERNEL) || defined(_STANDALONE))
43 #include <stdbool.h>
44 #endif
45 
46 /*
47  * Kernel resident routing tables.
48  *
49  * The routing tables are initialized when interface addresses
50  * are set by making entries for all directly connected interfaces.
51  */
52 
53 /*
54  * A route consists of a destination address and a reference
55  * to a routing entry.  These are often held by protocols
56  * in their control blocks, e.g. inpcb.
57  */
58 struct route {
59 	struct	rtentry		*_ro_rt;
60 	struct	sockaddr	*ro_sa;
61 	LIST_ENTRY(route)	ro_rtcache_next;
62 	bool			ro_invalid;
63 };
64 
65 /*
66  * These numbers are used by reliable protocols for determining
67  * retransmission behavior and are included in the routing structure.
68  */
69 struct rt_metrics {
70 	uint64_t rmx_locks;	/* Kernel must leave these values alone */
71 	uint64_t rmx_mtu;	/* MTU for this path */
72 	uint64_t rmx_hopcount;	/* max hops expected */
73 	uint64_t rmx_recvpipe;	/* inbound delay-bandwidth product */
74 	uint64_t rmx_sendpipe;	/* outbound delay-bandwidth product */
75 	uint64_t rmx_ssthresh;	/* outbound gateway buffer limit */
76 	uint64_t rmx_rtt;	/* estimated round trip time */
77 	uint64_t rmx_rttvar;	/* estimated rtt variance */
78 	time_t	rmx_expire;	/* lifetime for route, e.g. redirect */
79 	time_t	rmx_pksent;	/* packets sent using this route */
80 };
81 
82 /*
83  * rmx_rtt and rmx_rttvar are stored as microseconds;
84  * RTTTOPRHZ(rtt) converts to a value suitable for use
85  * by a protocol slowtimo counter.
86  */
87 #define	RTM_RTTUNIT	1000000	/* units for rtt, rttvar, as units per sec */
88 #define	RTTTOPRHZ(r)	((r) / (RTM_RTTUNIT / PR_SLOWHZ))
89 
90 /*
91  * We distinguish between routes to hosts and routes to networks,
92  * preferring the former if available.  For each route we infer
93  * the interface to use from the gateway address supplied when
94  * the route was entered.  Routes that forward packets through
95  * gateways are marked so that the output routines know to address the
96  * gateway rather than the ultimate destination.
97  */
98 #ifndef RNF_NORMAL
99 #include <net/radix.h>
100 #endif
101 struct rtentry {
102 	struct	radix_node rt_nodes[2];	/* tree glue, and other values */
103 #define	rt_mask(r)	((const struct sockaddr *)((r)->rt_nodes->rn_mask))
104 	struct	sockaddr *rt_gateway;	/* value */
105 	int	rt_flags;		/* up/down?, host/net */
106 	int	rt_refcnt;		/* # held references */
107 	uint64_t rt_use;			/* raw # packets forwarded */
108 	struct	ifnet *rt_ifp;		/* the answer: interface to use */
109 	struct	ifaddr *rt_ifa;		/* the answer: interface to use */
110 	uint32_t rt_ifa_seqno;
111 	void *	rt_llinfo;		/* pointer to link level info cache */
112 	struct	rt_metrics rt_rmx;	/* metrics used by rx'ing protocols */
113 	struct	rtentry *rt_gwroute;	/* implied entry for gatewayed routes */
114 	LIST_HEAD(, rttimer) rt_timer;  /* queue of timeouts for misc funcs */
115 	struct	rtentry *rt_parent;	/* parent of cloned route */
116 	struct	sockaddr *_rt_key;
117 	struct	sockaddr *rt_tag;	/* route tagging info */
118 };
119 
120 static inline const struct sockaddr *
rt_getkey(const struct rtentry * rt)121 rt_getkey(const struct rtentry *rt)
122 {
123 	return rt->_rt_key;
124 }
125 
126 /*
127  * Following structure necessary for 4.3 compatibility;
128  * We should eventually move it to a compat file.
129  */
130 struct ortentry {
131 	uint32_t rt_hash;		/* to speed lookups */
132 	struct	sockaddr rt_dst;	/* key */
133 	struct	sockaddr rt_gateway;	/* value */
134 	int16_t	rt_flags;		/* up/down?, host/net */
135 	int16_t	rt_refcnt;		/* # held references */
136 	uint32_t rt_use;		/* raw # packets forwarded */
137 	struct	ifnet *rt_ifp;		/* the answer: interface to use */
138 };
139 
140 #define	RTF_UP		0x1		/* route usable */
141 #define	RTF_GATEWAY	0x2		/* destination is a gateway */
142 #define	RTF_HOST	0x4		/* host entry (net otherwise) */
143 #define	RTF_REJECT	0x8		/* host or net unreachable */
144 #define	RTF_DYNAMIC	0x10		/* created dynamically (by redirect) */
145 #define	RTF_MODIFIED	0x20		/* modified dynamically (by redirect) */
146 #define RTF_DONE	0x40		/* message confirmed */
147 #define RTF_MASK	0x80		/* subnet mask present */
148 // #define RTF_CLONING	0x100		/* generate new routes on use */
149 #define RTF_CONNECTED	0x100		/* hosts on this route are neighbours */
150 // #define RTF_XRESOLVE	0x200		/* external daemon resolves name */
151 // #define RTF_LLINFO	0x400		/* generated by ARP or NDP */
152 #define RTF_LLDATA	0x400		/* used by apps to add/del L2 entries */
153 #define RTF_STATIC	0x800		/* manually added */
154 #define RTF_BLACKHOLE	0x1000		/* just discard pkts (during updates) */
155 // #define RTF_CLONED	0x2000		/* this is a cloned route */
156 #define RTF_PROTO2	0x4000		/* protocol specific routing flag */
157 #define RTF_PROTO1	0x8000		/* protocol specific routing flag */
158 #define RTF_SRC		0x10000		/* route has fixed source address */
159 #define RTF_ANNOUNCE	0x20000		/* announce new ARP or NDP entry */
160 #define RTF_LOCAL	0x40000		/* route represents a local address */
161 #define RTF_BROADCAST	0x80000		/* route represents a bcast address */
162 
163 /*
164  * Routing statistics.
165  */
166 struct	rtstat {
167 	uint64_t rts_badredirect;	/* bogus redirect calls */
168 	uint64_t rts_dynamic;		/* routes created by redirects */
169 	uint64_t rts_newgateway;	/* routes modified by redirects */
170 	uint64_t rts_unreach;		/* lookups which failed */
171 	uint64_t rts_wildcard;		/* lookups satisfied by a wildcard */
172 };
173 
174 /*
175  * Structures for routing messages.  By forcing the first member to be aligned
176  * at a 64-bit boundary, we also force the size to be a multiple of 64-bits.
177  */
178 
179 #if !defined(_KERNEL) || !defined(COMPAT_RTSOCK)
180 /*
181  * If we aren't being compiled for backwards compatiblity, enforce 64-bit
182  * alignment so any routing message is the same regardless if the kernel
183  * is an ILP32 or LP64 kernel.
184  */
185 #define	__align64	__aligned(sizeof(uint64_t))
186 #else
187 #define	__align64
188 #endif
189 
190 struct rt_msghdr {
191 	u_short	rtm_msglen __align64;
192 				/* to skip over non-understood messages */
193 	u_char	rtm_version;	/* future binary compatibility */
194 	u_char	rtm_type;	/* message type */
195 	u_short	rtm_index;	/* index for associated ifp */
196 	int	rtm_flags;	/* flags, incl. kern & message, e.g. DONE */
197 	int	rtm_addrs;	/* bitmask identifying sockaddrs in msg */
198 	pid_t	rtm_pid;	/* identify sender */
199 	int	rtm_seq;	/* for sender to identify action */
200 	int	rtm_errno;	/* why failed */
201 	int	rtm_use;	/* from rtentry */
202 	int	rtm_inits;	/* which metrics we are initializing */
203 	struct	rt_metrics rtm_rmx __align64;
204 				/* metrics themselves */
205 };
206 
207 #undef __align64
208 
209 #define RTM_VERSION	4	/* Up the ante and ignore older versions */
210 
211 #define RTM_ADD		0x1	/* Add Route */
212 #define RTM_DELETE	0x2	/* Delete Route */
213 #define RTM_CHANGE	0x3	/* Change Metrics or flags */
214 #define RTM_GET		0x4	/* Report Metrics */
215 #define RTM_LOSING	0x5	/* Kernel Suspects Partitioning */
216 #define RTM_REDIRECT	0x6	/* Told to use different route */
217 #define RTM_MISS	0x7	/* Lookup failed on this address */
218 #define RTM_LOCK	0x8	/* fix specified metrics */
219 #define RTM_OLDADD	0x9	/* caused by SIOCADDRT */
220 #define RTM_OLDDEL	0xa	/* caused by SIOCDELRT */
221 // #define RTM_RESOLVE	0xb	/* req to resolve dst to LL addr */
222 #define RTM_NEWADDR	0xc	/* address being added to iface */
223 #define RTM_DELADDR	0xd	/* address being removed from iface */
224 #define RTM_OOIFINFO	0xe	/* Old (pre-1.5) RTM_IFINFO message */
225 #define RTM_OIFINFO	0xf	/* Old (pre-64bit time) RTM_IFINFO message */
226 #define	RTM_IFANNOUNCE	0x10	/* iface arrival/departure */
227 #define	RTM_IEEE80211	0x11	/* IEEE80211 wireless event */
228 #define	RTM_SETGATE	0x12	/* set prototype gateway for clones
229 				 * (see example in arp_rtrequest).
230 				 */
231 #define	RTM_LLINFO_UPD	0x13	/* indication to ARP/NDP/etc. that link-layer
232 				 * address has changed
233 				 */
234 #define RTM_IFINFO	0x14	/* iface/link going up/down etc. */
235 #define RTM_CHGADDR	0x15	/* address properties changed */
236 
237 #define RTV_MTU		0x1	/* init or lock _mtu */
238 #define RTV_HOPCOUNT	0x2	/* init or lock _hopcount */
239 #define RTV_EXPIRE	0x4	/* init or lock _expire */
240 #define RTV_RPIPE	0x8	/* init or lock _recvpipe */
241 #define RTV_SPIPE	0x10	/* init or lock _sendpipe */
242 #define RTV_SSTHRESH	0x20	/* init or lock _ssthresh */
243 #define RTV_RTT		0x40	/* init or lock _rtt */
244 #define RTV_RTTVAR	0x80	/* init or lock _rttvar */
245 
246 /*
247  * Bitmask values for rtm_addr.
248  */
249 #define RTA_DST		0x1	/* destination sockaddr present */
250 #define RTA_GATEWAY	0x2	/* gateway sockaddr present */
251 #define RTA_NETMASK	0x4	/* netmask sockaddr present */
252 #define RTA_GENMASK	0x8	/* cloning mask sockaddr present */
253 #define RTA_IFP		0x10	/* interface name sockaddr present */
254 #define RTA_IFA		0x20	/* interface addr sockaddr present */
255 #define RTA_AUTHOR	0x40	/* sockaddr for author of redirect */
256 #define RTA_BRD		0x80	/* for NEWADDR, broadcast or p-p dest addr */
257 #define RTA_TAG		0x100	/* route tag */
258 
259 /*
260  * Index offsets for sockaddr array for alternate internal encoding.
261  */
262 #define RTAX_DST	0	/* destination sockaddr present */
263 #define RTAX_GATEWAY	1	/* gateway sockaddr present */
264 #define RTAX_NETMASK	2	/* netmask sockaddr present */
265 #define RTAX_GENMASK	3	/* cloning mask sockaddr present */
266 #define RTAX_IFP	4	/* interface name sockaddr present */
267 #define RTAX_IFA	5	/* interface addr sockaddr present */
268 #define RTAX_AUTHOR	6	/* sockaddr for author of redirect */
269 #define RTAX_BRD	7	/* for NEWADDR, broadcast or p-p dest addr */
270 #define RTAX_TAG	8	/* route tag */
271 #define RTAX_MAX	9	/* size of array to allocate */
272 
273 #define RT_ROUNDUP2(a, n)	((a) > 0 ? (1 + (((a) - 1) | ((n) - 1))) : (n))
274 #define RT_ROUNDUP(a)		RT_ROUNDUP2((a), sizeof(uint64_t))
275 #define RT_ADVANCE(x, n)	(x += RT_ROUNDUP((n)->sa_len))
276 
277 struct rt_addrinfo {
278 	int	rti_addrs;
279 	const struct	sockaddr *rti_info[RTAX_MAX];
280 	int	rti_flags;
281 	struct	ifaddr *rti_ifa;
282 	struct	ifnet *rti_ifp;
283 };
284 
285 struct route_cb {
286 	int	ip_count;
287 	int	ip6_count;
288 	int	unused1;
289 	int	mpls_count;
290 	int	any_count;
291 };
292 
293 /*
294  * This structure, and the prototypes for the rt_timer_{init,remove_all,
295  * add,timer} functions all used with the kind permission of BSDI.
296  * These allow functions to be called for routes at specific times.
297  */
298 
299 struct rttimer {
300 	TAILQ_ENTRY(rttimer)	rtt_next;  /* entry on timer queue */
301 	LIST_ENTRY(rttimer) 	rtt_link;  /* multiple timers per rtentry */
302 	struct rttimer_queue   *rtt_queue; /* back pointer to queue */
303 	struct rtentry         *rtt_rt;    /* Back pointer to the route */
304 	void		      (*rtt_func)(struct rtentry *, struct rttimer *);
305 	time_t          	rtt_time;  /* When this timer was registered */
306 };
307 
308 struct rttimer_queue {
309 	long				rtq_timeout;
310 	unsigned long			rtq_count;
311 	TAILQ_HEAD(, rttimer)		rtq_head;
312 	LIST_ENTRY(rttimer_queue)	rtq_link;
313 };
314 
315 
316 struct rtbl;
317 typedef struct rtbl rtbl_t;
318 
319 #ifdef _KERNEL
320 
321 struct rtbl {
322 	struct radix_node_head t_rnh;
323 };
324 
325 struct rt_walkarg {
326 	int	w_op;
327 	int	w_arg;
328 	int	w_given;
329 	int	w_needed;
330 	void *	w_where;
331 	int	w_tmemsize;
332 	int	w_tmemneeded;
333 	void *	w_tmem;
334 };
335 
336 #if 0
337 #define	RT_DPRINTF(__fmt, ...)	do { } while (/*CONSTCOND*/0)
338 #else
339 #define	RT_DPRINTF(__fmt, ...)	/* do nothing */
340 #endif
341 
342 struct rtwalk {
343 	int (*rw_f)(struct rtentry *, void *);
344 	void *rw_v;
345 };
346 
347 /*
348  * Global data specific to the routing socket.
349  */
350 struct route_info {
351 	struct sockaddr ri_dst;
352 	struct sockaddr ri_src;
353 	struct route_cb ri_cb;
354 	int ri_maxqlen;
355 	struct ifqueue ri_intrq;
356 	void *ri_sih;
357 };
358 
359 extern	struct	route_info route_info;
360 extern	struct	rtstat	rtstat;
361 
362 struct socket;
363 
364 void	rt_init(void);
365 
366 int	rt_timer_add(struct rtentry *,
367 	    void(*)(struct rtentry *, struct rttimer *),
368 	    struct rttimer_queue *);
369 unsigned long
370 	rt_timer_count(struct rttimer_queue *);
371 void	rt_timer_init(void);
372 void	rt_timer_queue_change(struct rttimer_queue *, long);
373 struct rttimer_queue *
374 	rt_timer_queue_create(u_int);
375 void	rt_timer_queue_destroy(struct rttimer_queue *, int);
376 void	rt_timer_queue_remove_all(struct rttimer_queue *, int);
377 void	rt_timer_remove_all(struct rtentry *, int);
378 void	rt_timer_timer(void *);
379 
380 void	rt_newmsg(const int, const struct rtentry *);
381 struct rtentry *
382 	rtalloc1(const struct sockaddr *, int);
383 void	rtfree(struct rtentry *);
384 int	rtinit(struct ifaddr *, int, int);
385 void	rtredirect(const struct sockaddr *, const struct sockaddr *,
386 	    const struct sockaddr *, int, const struct sockaddr *,
387 	    struct rtentry **);
388 int	rtrequest(int, const struct sockaddr *,
389 	    const struct sockaddr *, const struct sockaddr *, int,
390 	    struct rtentry **);
391 int	rtrequest1(int, struct rt_addrinfo *, struct rtentry **);
392 int	rtrequest_newmsg(const int, const struct sockaddr *,
393 	    const struct sockaddr *, const struct sockaddr *, const int);
394 
395 int	rt_ifa_addlocal(struct ifaddr *);
396 int	rt_ifa_remlocal(struct ifaddr *, struct ifaddr *);
397 struct ifaddr *
398 	rt_get_ifa(struct rtentry *);
399 int	rt_getifa(struct rt_addrinfo *);
400 void	rt_replace_ifa(struct rtentry *, struct ifaddr *);
401 int	rt_setgate(struct rtentry *, const struct sockaddr *);
402 
403 const struct sockaddr *
404 	rt_settag(struct rtentry *, const struct sockaddr *);
405 struct sockaddr *
406 	rt_gettag(const struct rtentry *);
407 
408 int	rt_check_reject_route(const struct rtentry *, const struct ifnet *);
409 
410 static inline void
rt_assert_referenced(const struct rtentry * rt)411 rt_assert_referenced(const struct rtentry *rt)
412 {
413 
414 	KASSERT(rt->rt_refcnt > 0);
415 }
416 
417 void	rtcache_copy(struct route *, const struct route *);
418 void	rtcache_free(struct route *);
419 struct rtentry *
420 	rtcache_init(struct route *);
421 struct rtentry *
422 	rtcache_init_noclone(struct route *);
423 struct rtentry *
424 	rtcache_lookup2(struct route *, const struct sockaddr *, int,
425 	    int *);
426 int	rtcache_setdst(struct route *, const struct sockaddr *);
427 struct rtentry *
428 	rtcache_update(struct route *, int);
429 
430 static inline void
rtcache_invariants(const struct route * ro)431 rtcache_invariants(const struct route *ro)
432 {
433 	KASSERT(ro->ro_sa != NULL || ro->_ro_rt == NULL);
434 	KASSERT(!ro->ro_invalid || ro->_ro_rt != NULL);
435 	KASSERT(ro->_ro_rt == NULL || ro->_ro_rt->rt_refcnt > 0);
436 }
437 
438 static inline struct rtentry *
rtcache_lookup1(struct route * ro,const struct sockaddr * dst,int clone)439 rtcache_lookup1(struct route *ro, const struct sockaddr *dst, int clone)
440 {
441 	int hit;
442 
443 	return rtcache_lookup2(ro, dst, clone, &hit);
444 }
445 
446 static inline struct rtentry *
rtcache_lookup_noclone(struct route * ro,const struct sockaddr * dst)447 rtcache_lookup_noclone(struct route *ro, const struct sockaddr *dst)
448 {
449 	return rtcache_lookup1(ro, dst, 0);
450 }
451 
452 static inline struct rtentry *
rtcache_lookup(struct route * ro,const struct sockaddr * dst)453 rtcache_lookup(struct route *ro, const struct sockaddr *dst)
454 {
455 	return rtcache_lookup1(ro, dst, 1);
456 }
457 
458 static inline const struct sockaddr *
rtcache_getdst(const struct route * ro)459 rtcache_getdst(const struct route *ro)
460 {
461 	rtcache_invariants(ro);
462 	return ro->ro_sa;
463 }
464 
465 /* If the cache is not empty, and the cached route is still present
466  * in the routing table, return the cached route.  Otherwise, return
467  * NULL.
468  */
469 static inline struct rtentry *
rtcache_validate(const struct route * ro)470 rtcache_validate(const struct route *ro)
471 {
472 	struct rtentry *rt = ro->_ro_rt;
473 
474 	rtcache_invariants(ro);
475 
476 	if (ro->ro_invalid)
477 		return NULL;
478 
479 	if (rt != NULL && (rt->rt_flags & RTF_UP) != 0 && rt->rt_ifp != NULL)
480 		return rt;
481 	return NULL;
482 
483 }
484 
485 /* rtsock */
486 void	rt_ieee80211msg(struct ifnet *, int, void *, size_t);
487 void	rt_ifannouncemsg(struct ifnet *, int);
488 void	rt_ifmsg(struct ifnet *);
489 void	rt_missmsg(int, const struct rt_addrinfo *, int, int);
490 struct mbuf *
491 	rt_msg1(int, struct rt_addrinfo *, void *, int);
492 int	rt_msg3(int, struct rt_addrinfo *, void *, struct rt_walkarg *, int *);
493 void	rt_newaddrmsg(int, struct ifaddr *, int, struct rtentry *);
494 void	route_enqueue(struct mbuf *, int);
495 
496 /* rtbl */
497 int	rt_addaddr(rtbl_t *, struct rtentry *, const struct sockaddr *);
498 void	rt_assert_inactive(const struct rtentry *);
499 struct rtentry *
500 	rt_deladdr(rtbl_t *, const struct sockaddr *,
501 	    const struct sockaddr *);
502 rtbl_t *rt_gettable(sa_family_t);
503 int	rt_inithead(rtbl_t **, int);
504 struct rtentry *
505 	rt_lookup(rtbl_t *, const struct sockaddr *,
506 	    const struct sockaddr *);
507 struct rtentry *
508 	rt_matchaddr(rtbl_t *, const struct sockaddr *);
509 int	rt_refines(const struct sockaddr *, const struct sockaddr *);
510 int	rt_walktree(sa_family_t, int (*)(struct rtentry *, void *), void *);
511 void	rtbl_init(void);
512 
513 #endif /* _KERNEL */
514 
515 #endif /* !_NET_ROUTE_H_ */
516