xref: /freebsd/sys/net/route.h (revision a3d9bf49b57923118c339642594246ef73872ee8)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
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	8.4 (Berkeley) 1/9/95
32  * $FreeBSD$
33  */
34 
35 #ifndef _NET_ROUTE_H_
36 #define _NET_ROUTE_H_
37 
38 #include <net/vnet.h>
39 
40 /*
41  * Kernel resident routing tables.
42  *
43  * The routing tables are initialized when interface addresses
44  * are set by making entries for all directly connected interfaces.
45  */
46 
47 /*
48  * Struct route consiste of a destination address,
49  * a route entry pointer, link-layer prepend data pointer along
50  * with its length.
51  */
52 struct route {
53 	struct	nhop_object *ro_nh;
54 	struct	llentry *ro_lle;
55 	/*
56 	 * ro_prepend and ro_plen are only used for bpf to pass in a
57 	 * preformed header.  They are not cacheable.
58 	 */
59 	char		*ro_prepend;
60 	uint16_t	ro_plen;
61 	uint16_t	ro_flags;
62 	uint16_t	ro_mtu;	/* saved ro_rt mtu */
63 	uint16_t	spare;
64 	struct	sockaddr ro_dst;
65 };
66 
67 #define	RT_L2_ME_BIT		2	/* dst L2 addr is our address */
68 #define	RT_MAY_LOOP_BIT		3	/* dst may require loop copy */
69 #define	RT_HAS_HEADER_BIT	4	/* mbuf already have its header prepended */
70 
71 #define	RT_L2_ME		(1 << RT_L2_ME_BIT)		/* 0x0004 */
72 #define	RT_MAY_LOOP		(1 << RT_MAY_LOOP_BIT)		/* 0x0008 */
73 #define	RT_HAS_HEADER		(1 << RT_HAS_HEADER_BIT)	/* 0x0010 */
74 
75 #define	RT_REJECT		0x0020		/* Destination is reject */
76 #define	RT_BLACKHOLE		0x0040		/* Destination is blackhole */
77 #define	RT_HAS_GW		0x0080		/* Destination has GW  */
78 #define	RT_LLE_CACHE		0x0100		/* Cache link layer  */
79 
80 struct rt_metrics {
81 	u_long	rmx_locks;	/* Kernel must leave these values alone */
82 	u_long	rmx_mtu;	/* MTU for this path */
83 	u_long	rmx_hopcount;	/* max hops expected */
84 	u_long	rmx_expire;	/* lifetime for route, e.g. redirect */
85 	u_long	rmx_recvpipe;	/* inbound delay-bandwidth product */
86 	u_long	rmx_sendpipe;	/* outbound delay-bandwidth product */
87 	u_long	rmx_ssthresh;	/* outbound gateway buffer limit */
88 	u_long	rmx_rtt;	/* estimated round trip time */
89 	u_long	rmx_rttvar;	/* estimated rtt variance */
90 	u_long	rmx_pksent;	/* packets sent using this route */
91 	u_long	rmx_weight;	/* route weight */
92 	u_long	rmx_nhidx;	/* route nexhop index */
93 	u_long	rmx_filler[2];	/* will be used for T/TCP later */
94 };
95 
96 /*
97  * rmx_rtt and rmx_rttvar are stored as microseconds;
98  * RTTTOPRHZ(rtt) converts to a value suitable for use
99  * by a protocol slowtimo counter.
100  */
101 #define	RTM_RTTUNIT	1000000	/* units for rtt, rttvar, as units per sec */
102 #define	RTTTOPRHZ(r)	((r) / (RTM_RTTUNIT / PR_SLOWHZ))
103 
104 /* lle state is exported in rmx_state rt_metrics field */
105 #define	rmx_state	rmx_weight
106 
107 /* default route weight */
108 #define	RT_DEFAULT_WEIGHT	1
109 #define	RT_MAX_WEIGHT		16777215	/* 3 bytes */
110 
111 /*
112  * Keep a generation count of routing table, incremented on route addition,
113  * so we can invalidate caches.  This is accessed without a lock, as precision
114  * is not required.
115  */
116 typedef volatile u_int rt_gen_t;	/* tree generation (for adds) */
117 #define RT_GEN(fibnum, af)	rt_tables_get_gen(fibnum, af)
118 
119 #define	RT_DEFAULT_FIB	0	/* Explicitly mark fib=0 restricted cases */
120 #define	RT_ALL_FIBS	-1	/* Announce event for every fib */
121 #ifdef _KERNEL
122 VNET_DECLARE(uint32_t, _rt_numfibs);	/* number of existing route tables */
123 #define	V_rt_numfibs		VNET(_rt_numfibs)
124 /* temporary compat arg */
125 #define	rt_numfibs		V_rt_numfibs
126 VNET_DECLARE(u_int, rt_add_addr_allfibs); /* Announce interfaces to all fibs */
127 #define	V_rt_add_addr_allfibs	VNET(rt_add_addr_allfibs)
128 #endif
129 
130 /*
131  * We distinguish between routes to hosts and routes to networks,
132  * preferring the former if available.  For each route we infer
133  * the interface to use from the gateway address supplied when
134  * the route was entered.  Routes that forward packets through
135  * gateways are marked so that the output routines know to address the
136  * gateway rather than the ultimate destination.
137  */
138 #define	RTF_UP		0x1		/* route usable */
139 #define	RTF_GATEWAY	0x2		/* destination is a gateway */
140 #define	RTF_HOST	0x4		/* host entry (net otherwise) */
141 #define	RTF_REJECT	0x8		/* host or net unreachable */
142 #define	RTF_DYNAMIC	0x10		/* created dynamically (by redirect) */
143 #define	RTF_MODIFIED	0x20		/* modified dynamically (by redirect) */
144 #define RTF_DONE	0x40		/* message confirmed */
145 /*			0x80		   unused, was RTF_DELCLONE */
146 /*			0x100		   unused, was RTF_CLONING */
147 #define RTF_XRESOLVE	0x200		/* external daemon resolves name */
148 #define RTF_LLINFO	0x400		/* DEPRECATED - exists ONLY for backward
149 					   compatibility */
150 #define RTF_LLDATA	0x400		/* used by apps to add/del L2 entries */
151 #define RTF_STATIC	0x800		/* manually added */
152 #define RTF_BLACKHOLE	0x1000		/* just discard pkts (during updates) */
153 #define RTF_PROTO2	0x4000		/* protocol specific routing flag */
154 #define RTF_PROTO1	0x8000		/* protocol specific routing flag */
155 /*			0x10000		   unused, was RTF_PRCLONING */
156 /*			0x20000		   unused, was RTF_WASCLONED */
157 #define RTF_PROTO3	0x40000		/* protocol specific routing flag */
158 #define	RTF_FIXEDMTU	0x80000		/* MTU was explicitly specified */
159 #define RTF_PINNED	0x100000	/* route is immutable */
160 #define	RTF_LOCAL	0x200000 	/* route represents a local address */
161 #define	RTF_BROADCAST	0x400000	/* route represents a bcast address */
162 #define	RTF_MULTICAST	0x800000	/* route represents a mcast address */
163 					/* 0x8000000 and up unassigned */
164 #define	RTF_STICKY	 0x10000000	/* always route dst->src */
165 
166 #define	RTF_RNH_LOCKED	 0x40000000	/* radix node head is locked */
167 
168 #define	RTF_GWFLAG_COMPAT 0x80000000	/* a compatibility bit for interacting
169 					   with existing routing apps */
170 
171 /* Mask of RTF flags that are allowed to be modified by RTM_CHANGE. */
172 #define RTF_FMASK	\
173 	(RTF_PROTO1 | RTF_PROTO2 | RTF_PROTO3 | RTF_BLACKHOLE | \
174 	 RTF_REJECT | RTF_STATIC | RTF_STICKY)
175 
176 /*
177  * fib_ nexthop API flags.
178  */
179 
180 /* Consumer-visible nexthop info flags */
181 #define	NHF_REJECT		0x0010	/* RTF_REJECT */
182 #define	NHF_BLACKHOLE		0x0020	/* RTF_BLACKHOLE */
183 #define	NHF_REDIRECT		0x0040	/* RTF_DYNAMIC|RTF_MODIFIED */
184 #define	NHF_DEFAULT		0x0080	/* Default route */
185 #define	NHF_BROADCAST		0x0100	/* RTF_BROADCAST */
186 #define	NHF_GATEWAY		0x0200	/* RTF_GATEWAY */
187 #define	NHF_HOST		0x0400	/* RTF_HOST */
188 
189 /* Nexthop request flags */
190 #define	NHR_NONE		0x00	/* empty flags field */
191 #define	NHR_IFAIF		0x01	/* Return ifa_ifp interface */
192 #define	NHR_REF			0x02	/* For future use */
193 
194 /* uRPF */
195 #define	NHR_NODEFAULT		0x04	/* do not consider default route */
196 
197 /* Control plane route request flags */
198 #define	NHR_COPY		0x100	/* Copy rte data */
199 
200 /*
201  * Routing statistics.
202  */
203 struct rtstat {
204 	uint64_t rts_badredirect;	/* bogus redirect calls */
205 	uint64_t rts_dynamic;		/* routes created by redirects */
206 	uint64_t rts_newgateway;	/* routes modified by redirects */
207 	uint64_t rts_unreach;		/* lookups which failed */
208 	uint64_t rts_wildcard;		/* lookups satisfied by a wildcard */
209 	uint64_t rts_nh_idx_alloc_failure;	/* nexthop index alloc failure*/
210 	uint64_t rts_nh_alloc_failure;	/* nexthop allocation failure*/
211 };
212 
213 /*
214  * Structures for routing messages.
215  */
216 struct rt_msghdr {
217 	u_short	rtm_msglen;	/* to skip over non-understood messages */
218 	u_char	rtm_version;	/* future binary compatibility */
219 	u_char	rtm_type;	/* message type */
220 	u_short	rtm_index;	/* index for associated ifp */
221 	u_short _rtm_spare1;
222 	int	rtm_flags;	/* flags, incl. kern & message, e.g. DONE */
223 	int	rtm_addrs;	/* bitmask identifying sockaddrs in msg */
224 	pid_t	rtm_pid;	/* identify sender */
225 	int	rtm_seq;	/* for sender to identify action */
226 	int	rtm_errno;	/* why failed */
227 	int	rtm_fmask;	/* bitmask used in RTM_CHANGE message */
228 	u_long	rtm_inits;	/* which metrics we are initializing */
229 	struct	rt_metrics rtm_rmx; /* metrics themselves */
230 };
231 
232 #define RTM_VERSION	5	/* Up the ante and ignore older versions */
233 
234 /*
235  * Message types.
236  *
237  * The format for each message is annotated below using the following
238  * identifiers:
239  *
240  * (1) struct rt_msghdr
241  * (2) struct ifa_msghdr
242  * (3) struct if_msghdr
243  * (4) struct ifma_msghdr
244  * (5) struct if_announcemsghdr
245  *
246  */
247 #define	RTM_ADD		0x1	/* (1) Add Route */
248 #define	RTM_DELETE	0x2	/* (1) Delete Route */
249 #define	RTM_CHANGE	0x3	/* (1) Change Metrics or flags */
250 #define	RTM_GET		0x4	/* (1) Report Metrics */
251 #define	RTM_LOSING	0x5	/* (1) Kernel Suspects Partitioning */
252 #define	RTM_REDIRECT	0x6	/* (1) Told to use different route */
253 #define	RTM_MISS	0x7	/* (1) Lookup failed on this address */
254 #define	RTM_LOCK	0x8	/* (1) fix specified metrics */
255 		    /*	0x9  */
256 		    /*	0xa  */
257 #define	RTM_RESOLVE	0xb	/* (1) req to resolve dst to LL addr */
258 #define	RTM_NEWADDR	0xc	/* (2) address being added to iface */
259 #define	RTM_DELADDR	0xd	/* (2) address being removed from iface */
260 #define	RTM_IFINFO	0xe	/* (3) iface going up/down etc. */
261 #define	RTM_NEWMADDR	0xf	/* (4) mcast group membership being added to if */
262 #define	RTM_DELMADDR	0x10	/* (4) mcast group membership being deleted */
263 #define	RTM_IFANNOUNCE	0x11	/* (5) iface arrival/departure */
264 #define	RTM_IEEE80211	0x12	/* (5) IEEE80211 wireless event */
265 
266 /*
267  * Bitmask values for rtm_inits and rmx_locks.
268  */
269 #define RTV_MTU		0x1	/* init or lock _mtu */
270 #define RTV_HOPCOUNT	0x2	/* init or lock _hopcount */
271 #define RTV_EXPIRE	0x4	/* init or lock _expire */
272 #define RTV_RPIPE	0x8	/* init or lock _recvpipe */
273 #define RTV_SPIPE	0x10	/* init or lock _sendpipe */
274 #define RTV_SSTHRESH	0x20	/* init or lock _ssthresh */
275 #define RTV_RTT		0x40	/* init or lock _rtt */
276 #define RTV_RTTVAR	0x80	/* init or lock _rttvar */
277 #define RTV_WEIGHT	0x100	/* init or lock _weight */
278 
279 /*
280  * Bitmask values for rtm_addrs.
281  */
282 #define RTA_DST		0x1	/* destination sockaddr present */
283 #define RTA_GATEWAY	0x2	/* gateway sockaddr present */
284 #define RTA_NETMASK	0x4	/* netmask sockaddr present */
285 #define RTA_GENMASK	0x8	/* cloning mask sockaddr present */
286 #define RTA_IFP		0x10	/* interface name sockaddr present */
287 #define RTA_IFA		0x20	/* interface addr sockaddr present */
288 #define RTA_AUTHOR	0x40	/* sockaddr for author of redirect */
289 #define RTA_BRD		0x80	/* for NEWADDR, broadcast or p-p dest addr */
290 
291 /*
292  * Index offsets for sockaddr array for alternate internal encoding.
293  */
294 #define RTAX_DST	0	/* destination sockaddr present */
295 #define RTAX_GATEWAY	1	/* gateway sockaddr present */
296 #define RTAX_NETMASK	2	/* netmask sockaddr present */
297 #define RTAX_GENMASK	3	/* cloning mask sockaddr present */
298 #define RTAX_IFP	4	/* interface name sockaddr present */
299 #define RTAX_IFA	5	/* interface addr sockaddr present */
300 #define RTAX_AUTHOR	6	/* sockaddr for author of redirect */
301 #define RTAX_BRD	7	/* for NEWADDR, broadcast or p-p dest addr */
302 #define RTAX_MAX	8	/* size of array to allocate */
303 
304 struct rtentry;
305 struct nhop_object;
306 typedef int rt_filter_f_t(const struct rtentry *, const struct nhop_object *,
307     void *);
308 
309 struct rt_addrinfo {
310 	int	rti_addrs;			/* Route RTF_ flags */
311 	int	rti_flags;			/* Route RTF_ flags */
312 	struct	sockaddr *rti_info[RTAX_MAX];	/* Sockaddr data */
313 	struct	ifaddr *rti_ifa;		/* value of rt_ifa addr */
314 	struct	ifnet *rti_ifp;			/* route interface */
315 	rt_filter_f_t	*rti_filter;		/* filter function */
316 	void	*rti_filterdata;		/* filter paramenters */
317 	u_long	rti_mflags;			/* metrics RTV_ flags */
318 	u_long	rti_spare;			/* Will be used for fib */
319 	struct	rt_metrics *rti_rmx;		/* Pointer to route metrics */
320 };
321 
322 /*
323  * This macro returns the size of a struct sockaddr when passed
324  * through a routing socket. Basically we round up sa_len to
325  * a multiple of sizeof(long), with a minimum of sizeof(long).
326  * The case sa_len == 0 should only apply to empty structures.
327  */
328 #define SA_SIZE(sa)						\
329     (  (((struct sockaddr *)(sa))->sa_len == 0) ?		\
330 	sizeof(long)		:				\
331 	1 + ( (((struct sockaddr *)(sa))->sa_len - 1) | (sizeof(long) - 1) ) )
332 
333 #define	sa_equal(a, b) (	\
334     (((const struct sockaddr *)(a))->sa_len == ((const struct sockaddr *)(b))->sa_len) && \
335     (bcmp((a), (b), ((const struct sockaddr *)(b))->sa_len) == 0))
336 
337 #ifdef _KERNEL
338 
339 #define RT_LINK_IS_UP(ifp)	(!((ifp)->if_capabilities & IFCAP_LINKSTATE) \
340 				 || (ifp)->if_link_state == LINK_STATE_UP)
341 
342 #define	RO_NHFREE(_ro) do {					\
343 	if ((_ro)->ro_nh) {					\
344 		NH_FREE((_ro)->ro_nh);				\
345 		(_ro)->ro_nh = NULL;				\
346 	}							\
347 } while (0)
348 
349 #define	RO_INVALIDATE_CACHE(ro) do {					\
350 		if ((ro)->ro_lle != NULL) {				\
351 			LLE_FREE((ro)->ro_lle);				\
352 			(ro)->ro_lle = NULL;				\
353 		}							\
354 		if ((ro)->ro_nh != NULL) {				\
355 			NH_FREE((ro)->ro_nh);				\
356 			(ro)->ro_nh = NULL;				\
357 		}							\
358 	} while (0)
359 
360 /*
361  * Validate a cached route based on a supplied cookie.  If there is an
362  * out-of-date cache, simply free it.  Update the generation number
363  * for the new allocation
364  */
365 #define NH_VALIDATE(ro, cookiep, fibnum) do {				\
366 	rt_gen_t cookie = RT_GEN(fibnum, (ro)->ro_dst.sa_family);	\
367 	if (*(cookiep) != cookie) {					\
368 		RO_INVALIDATE_CACHE(ro);				\
369 		*(cookiep) = cookie;					\
370 	}								\
371 } while (0)
372 
373 struct ifmultiaddr;
374 struct rib_head;
375 
376 void	 rt_ieee80211msg(struct ifnet *, int, void *, size_t);
377 void	 rt_ifannouncemsg(struct ifnet *, int);
378 void	 rt_ifmsg(struct ifnet *);
379 void	 rt_missmsg(int, struct rt_addrinfo *, int, int);
380 void	 rt_missmsg_fib(int, struct rt_addrinfo *, int, int, int);
381 void	 rt_newaddrmsg_fib(int, struct ifaddr *, struct rtentry *, int);
382 int	 rt_addrmsg(int, struct ifaddr *, int);
383 int	 rt_routemsg(int, struct rtentry *, struct ifnet *ifp, int, int);
384 int	 rt_routemsg_info(int, struct rt_addrinfo *, int);
385 void	 rt_newmaddrmsg(int, struct ifmultiaddr *);
386 void 	 rt_maskedcopy(struct sockaddr *, struct sockaddr *, struct sockaddr *);
387 struct rib_head *rt_table_init(int, int, u_int);
388 void	rt_table_destroy(struct rib_head *);
389 u_int	rt_tables_get_gen(uint32_t table, sa_family_t family);
390 
391 int	rtsock_addrmsg(int, struct ifaddr *, int);
392 int	rtsock_routemsg(int, struct rtentry *, struct ifnet *ifp, int, int);
393 int	rtsock_routemsg_info(int, struct rt_addrinfo *, int);
394 
395 struct sockaddr *rtsock_fix_netmask(const struct sockaddr *dst,
396 	    const struct sockaddr *smask, struct sockaddr_storage *dmask);
397 
398 void	rt_updatemtu(struct ifnet *);
399 
400 void	rt_flushifroutes_af(struct ifnet *, int);
401 void	rt_flushifroutes(struct ifnet *ifp);
402 
403 /* XXX MRT COMPAT VERSIONS THAT SET UNIVERSE to 0 */
404 /* Thes are used by old code not yet converted to use multiple FIBS */
405 int	 rtinit(struct ifaddr *, int, int);
406 
407 /* XXX MRT NEW VERSIONS THAT USE FIBs
408  * For now the protocol indepedent versions are the same as the AF_INET ones
409  * but this will change..
410  */
411 int	 rtioctl_fib(u_long, caddr_t, u_int);
412 int	rib_lookup_info(uint32_t, const struct sockaddr *, uint32_t, uint32_t,
413 	    struct rt_addrinfo *);
414 void	rib_free_info(struct rt_addrinfo *info);
415 
416 /* New API */
417 struct nhop_object *rib_lookup(uint32_t fibnum, const struct sockaddr *dst,
418 	    uint32_t flags, uint32_t flowid);
419 #endif
420 
421 #endif
422