xref: /freebsd/sys/net/route.h (revision 1669d8afc64812c8d2d1d147ae1fd42ff441e1b1)
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 and a reference
45  * to a routing entry.  These are often held by protocols
46  * in their control blocks, e.g. inpcb.
47  */
48 struct route {
49 	struct	rtentry *ro_rt;
50 	struct	sockaddr ro_dst;
51 };
52 
53 /*
54  * These numbers are used by reliable protocols for determining
55  * retransmission behavior and are included in the routing structure.
56  */
57 struct rt_metrics_lite {
58 	u_long	rmx_mtu;	/* MTU for this path */
59 	u_long	rmx_expire;	/* lifetime for route, e.g. redirect */
60 	u_long	rmx_pksent;	/* packets sent using this route */
61 };
62 
63 struct rt_metrics {
64 	u_long	rmx_locks;	/* Kernel must leave these values alone */
65 	u_long	rmx_mtu;	/* MTU for this path */
66 	u_long	rmx_hopcount;	/* max hops expected */
67 	u_long	rmx_expire;	/* lifetime for route, e.g. redirect */
68 	u_long	rmx_recvpipe;	/* inbound delay-bandwidth product */
69 	u_long	rmx_sendpipe;	/* outbound delay-bandwidth product */
70 	u_long	rmx_ssthresh;	/* outbound gateway buffer limit */
71 	u_long	rmx_rtt;	/* estimated round trip time */
72 	u_long	rmx_rttvar;	/* estimated rtt variance */
73 	u_long	rmx_pksent;	/* packets sent using this route */
74 	u_long	rmx_filler[4];	/* will be used for T/TCP later */
75 };
76 
77 /*
78  * rmx_rtt and rmx_rttvar are stored as microseconds;
79  * RTTTOPRHZ(rtt) converts to a value suitable for use
80  * by a protocol slowtimo counter.
81  */
82 #define	RTM_RTTUNIT	1000000	/* units for rtt, rttvar, as units per sec */
83 #define	RTTTOPRHZ(r)	((r) / (RTM_RTTUNIT / PR_SLOWHZ))
84 
85 /*
86  * XXX kernel function pointer `rt_output' is visible to applications.
87  */
88 struct mbuf;
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 	/*
104 	 * XXX struct rtentry must begin with a struct radix_node (or two!)
105 	 * because the code does some casts of a 'struct radix_node *'
106 	 * to a 'struct rtentry *'
107 	 */
108 #define	rt_key(r)	(*((struct sockaddr **)(&(r)->rt_nodes->rn_key)))
109 #define	rt_mask(r)	(*((struct sockaddr **)(&(r)->rt_nodes->rn_mask)))
110 	struct	sockaddr *rt_gateway;	/* value */
111 	u_long	rt_flags;		/* up/down?, host/net */
112 	struct	ifnet *rt_ifp;		/* the answer: interface to use */
113 	struct	ifaddr *rt_ifa;		/* the answer: interface address to use */
114 	struct	rt_metrics_lite rt_rmx;	/* metrics used by rx'ing protocols */
115 	long	rt_refcnt;		/* # held references */
116 	struct	sockaddr *rt_genmask;	/* for generation of cloned routes */
117 	caddr_t	rt_llinfo;		/* pointer to link level info cache */
118 	struct	rtentry *rt_gwroute;	/* implied entry for gatewayed routes */
119 	struct	rtentry *rt_parent; 	/* cloning parent of this route */
120 #ifdef _KERNEL
121 	/* XXX ugly, user apps use this definition but don't have a mtx def */
122 	struct	mtx rt_mtx;		/* mutex for routing entry */
123 #endif
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 	u_long	rt_hash;		/* to speed lookups */
132 	struct	sockaddr rt_dst;	/* key */
133 	struct	sockaddr rt_gateway;	/* value */
134 	short	rt_flags;		/* up/down?, host/net */
135 	short	rt_refcnt;		/* # held references */
136 	u_long	rt_use;			/* raw # packets forwarded */
137 	struct	ifnet *rt_ifp;		/* the answer: interface to use */
138 };
139 
140 #define rt_use rt_rmx.rmx_pksent
141 
142 #define	RTF_UP		0x1		/* route usable */
143 #define	RTF_GATEWAY	0x2		/* destination is a gateway */
144 #define	RTF_HOST	0x4		/* host entry (net otherwise) */
145 #define	RTF_REJECT	0x8		/* host or net unreachable */
146 #define	RTF_DYNAMIC	0x10		/* created dynamically (by redirect) */
147 #define	RTF_MODIFIED	0x20		/* modified dynamically (by redirect) */
148 #define RTF_DONE	0x40		/* message confirmed */
149 /*			0x80		   unused, was RTF_DELCLONE */
150 #define RTF_CLONING	0x100		/* generate new routes on use */
151 #define RTF_XRESOLVE	0x200		/* external daemon resolves name */
152 #define RTF_LLINFO	0x400		/* generated by link layer (e.g. ARP) */
153 #define RTF_STATIC	0x800		/* manually added */
154 #define RTF_BLACKHOLE	0x1000		/* just discard pkts (during updates) */
155 #define RTF_PROTO2	0x4000		/* protocol specific routing flag */
156 #define RTF_PROTO1	0x8000		/* protocol specific routing flag */
157 
158 /* XXX: temporary to stay API/ABI compatible with userland */
159 #ifndef _KERNEL
160 #define RTF_PRCLONING	0x10000		/* unused, for compatibility */
161 #endif
162 
163 #define RTF_WASCLONED	0x20000		/* route generated through cloning */
164 #define RTF_PROTO3	0x40000		/* protocol specific routing flag */
165 /*			0x80000		   unused */
166 #define RTF_PINNED	0x100000	/* future use */
167 #define	RTF_LOCAL	0x200000 	/* route represents a local address */
168 #define	RTF_BROADCAST	0x400000	/* route represents a bcast address */
169 #define	RTF_MULTICAST	0x800000	/* route represents a mcast address */
170 					/* 0x1000000 and up unassigned */
171 
172 /* Mask of RTF flags that are allowed to be modified by RTM_CHANGE. */
173 #define RTF_FMASK	\
174 	(RTF_PROTO1 | RTF_PROTO2 | RTF_PROTO3 | RTF_BLACKHOLE | \
175 	 RTF_REJECT | RTF_STATIC)
176 
177 /*
178  * Routing statistics.
179  */
180 struct	rtstat {
181 	short	rts_badredirect;	/* bogus redirect calls */
182 	short	rts_dynamic;		/* routes created by redirects */
183 	short	rts_newgateway;		/* routes modified by redirects */
184 	short	rts_unreach;		/* lookups which failed */
185 	short	rts_wildcard;		/* lookups satisfied by a wildcard */
186 };
187 /*
188  * Structures for routing messages.
189  */
190 struct rt_msghdr {
191 	u_short	rtm_msglen;	/* to skip over non-understood messages */
192 	u_char	rtm_version;	/* future binary compatibility */
193 	u_char	rtm_type;	/* message type */
194 	u_short	rtm_index;	/* index for associated ifp */
195 	int	rtm_flags;	/* flags, incl. kern & message, e.g. DONE */
196 	int	rtm_addrs;	/* bitmask identifying sockaddrs in msg */
197 	pid_t	rtm_pid;	/* identify sender */
198 	int	rtm_seq;	/* for sender to identify action */
199 	int	rtm_errno;	/* why failed */
200 	int	rtm_fmask;	/* bitmask used in RTM_CHANGE message */
201 #define	rtm_use	rtm_fmask	/* deprecated, use rtm_rmx->rmx_pksent */
202 	u_long	rtm_inits;	/* which metrics we are initializing */
203 	struct	rt_metrics rtm_rmx; /* metrics themselves */
204 };
205 
206 #define RTM_VERSION	5	/* Up the ante and ignore older versions */
207 
208 /*
209  * Message types.
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_IFINFO	0xe	/* iface going up/down etc. */
225 #define	RTM_NEWMADDR	0xf	/* mcast group membership being added to if */
226 #define	RTM_DELMADDR	0x10	/* mcast group membership being deleted */
227 #define	RTM_IFANNOUNCE	0x11	/* iface arrival/departure */
228 #define	RTM_IEEE80211	0x12	/* IEEE80211 wireless event */
229 
230 /*
231  * Bitmask values for rtm_inits and rmx_locks.
232  */
233 #define RTV_MTU		0x1	/* init or lock _mtu */
234 #define RTV_HOPCOUNT	0x2	/* init or lock _hopcount */
235 #define RTV_EXPIRE	0x4	/* init or lock _expire */
236 #define RTV_RPIPE	0x8	/* init or lock _recvpipe */
237 #define RTV_SPIPE	0x10	/* init or lock _sendpipe */
238 #define RTV_SSTHRESH	0x20	/* init or lock _ssthresh */
239 #define RTV_RTT		0x40	/* init or lock _rtt */
240 #define RTV_RTTVAR	0x80	/* init or lock _rttvar */
241 
242 /*
243  * Bitmask values for rtm_addrs.
244  */
245 #define RTA_DST		0x1	/* destination sockaddr present */
246 #define RTA_GATEWAY	0x2	/* gateway sockaddr present */
247 #define RTA_NETMASK	0x4	/* netmask sockaddr present */
248 #define RTA_GENMASK	0x8	/* cloning mask sockaddr present */
249 #define RTA_IFP		0x10	/* interface name sockaddr present */
250 #define RTA_IFA		0x20	/* interface addr sockaddr present */
251 #define RTA_AUTHOR	0x40	/* sockaddr for author of redirect */
252 #define RTA_BRD		0x80	/* for NEWADDR, broadcast or p-p dest addr */
253 
254 /*
255  * Index offsets for sockaddr array for alternate internal encoding.
256  */
257 #define RTAX_DST	0	/* destination sockaddr present */
258 #define RTAX_GATEWAY	1	/* gateway sockaddr present */
259 #define RTAX_NETMASK	2	/* netmask sockaddr present */
260 #define RTAX_GENMASK	3	/* cloning mask sockaddr present */
261 #define RTAX_IFP	4	/* interface name sockaddr present */
262 #define RTAX_IFA	5	/* interface addr sockaddr present */
263 #define RTAX_AUTHOR	6	/* sockaddr for author of redirect */
264 #define RTAX_BRD	7	/* for NEWADDR, broadcast or p-p dest addr */
265 #define RTAX_MAX	8	/* size of array to allocate */
266 
267 struct rt_addrinfo {
268 	int	rti_addrs;
269 	struct	sockaddr *rti_info[RTAX_MAX];
270 	int	rti_flags;
271 	struct	ifaddr *rti_ifa;
272 	struct	ifnet *rti_ifp;
273 };
274 
275 /*
276  * This macro returns the size of a struct sockaddr when passed
277  * through a routing socket. Basically we round up sa_len to
278  * a multiple of sizeof(long), with a minimum of sizeof(long).
279  * The check for a NULL pointer is just a convenience, probably never used.
280  * The case sa_len == 0 should only apply to empty structures.
281  */
282 #define SA_SIZE(sa)						\
283     (  (!(sa) || ((struct sockaddr *)(sa))->sa_len == 0) ?	\
284 	sizeof(long)		:				\
285 	1 + ( (((struct sockaddr *)(sa))->sa_len - 1) | (sizeof(long) - 1) ) )
286 
287 #ifdef _KERNEL
288 
289 #define	RT_LOCK_INIT(_rt) \
290 	mtx_init(&(_rt)->rt_mtx, "rtentry", NULL, MTX_DEF | MTX_DUPOK)
291 #define	RT_LOCK(_rt)		mtx_lock(&(_rt)->rt_mtx)
292 #define	RT_TRYLOCK(_rt)		mtx_trylock(&(_rt)->rt_mtx)
293 #define	RT_UNLOCK(_rt)		mtx_unlock(&(_rt)->rt_mtx)
294 #define	RT_LOCK_DESTROY(_rt)	mtx_destroy(&(_rt)->rt_mtx)
295 #define	RT_LOCK_ASSERT(_rt)	mtx_assert(&(_rt)->rt_mtx, MA_OWNED)
296 
297 #define	RT_ADDREF(_rt)	do {					\
298 	RT_LOCK_ASSERT(_rt);					\
299 	KASSERT((_rt)->rt_refcnt >= 0,				\
300 		("negative refcnt %ld", (_rt)->rt_refcnt));	\
301 	(_rt)->rt_refcnt++;					\
302 } while (0)
303 #define	RT_REMREF(_rt)	do {					\
304 	RT_LOCK_ASSERT(_rt);					\
305 	KASSERT((_rt)->rt_refcnt > 0,				\
306 		("bogus refcnt %ld", (_rt)->rt_refcnt));	\
307 	(_rt)->rt_refcnt--;					\
308 } while (0)
309 
310 #define	RTFREE_LOCKED(_rt) do {					\
311 		if ((_rt)->rt_refcnt <= 1)			\
312 			rtfree(_rt);				\
313 		else {						\
314 			RT_REMREF(_rt);				\
315 			RT_UNLOCK(_rt);				\
316 		}						\
317 		/* guard against invalid refs */		\
318 		_rt = 0;					\
319 	} while (0)
320 #define	RTFREE(_rt) do {					\
321 		RT_LOCK(_rt);					\
322 		RTFREE_LOCKED(_rt);				\
323 	} while (0)
324 
325 extern struct radix_node_head *rt_tables[AF_MAX+1];
326 
327 struct ifmultiaddr;
328 
329 int	 rt_getifa(struct rt_addrinfo *);
330 void	 rt_ieee80211msg(struct ifnet *, int, void *, size_t);
331 void	 rt_ifannouncemsg(struct ifnet *, int);
332 void	 rt_ifmsg(struct ifnet *);
333 void	 rt_missmsg(int, struct rt_addrinfo *, int, int);
334 void	 rt_newaddrmsg(int, struct ifaddr *, int, struct rtentry *);
335 void	 rt_newmaddrmsg(int, struct ifmultiaddr *);
336 int	 rt_setgate(struct rtentry *, struct sockaddr *, struct sockaddr *);
337 
338 /*
339  * Note the following locking behavior:
340  *
341  *    rtalloc_ign() and rtalloc() return ro->ro_rt unlocked
342  *
343  *    rtalloc1() returns a locked rtentry
344  *
345  *    rtfree() and RTFREE_LOCKED() require a locked rtentry
346  *
347  *    RTFREE() uses an unlocked entry.
348  */
349 
350 void	 rtalloc_ign(struct route *ro, u_long ignflags);
351 void	 rtalloc(struct route *ro); /* XXX deprecated, use rtalloc_ign(ro, 0) */
352 struct rtentry *rtalloc1(struct sockaddr *, int, u_long);
353 int	 rtexpunge(struct rtentry *);
354 void	 rtfree(struct rtentry *);
355 int	 rtinit(struct ifaddr *, int, int);
356 int	 rtioctl(u_long, caddr_t);
357 void	 rtredirect(struct sockaddr *, struct sockaddr *,
358 	    struct sockaddr *, int, struct sockaddr *);
359 int	 rtrequest(int, struct sockaddr *,
360 	    struct sockaddr *, struct sockaddr *, int, struct rtentry **);
361 int	 rtrequest1(int, struct rt_addrinfo *, struct rtentry **);
362 int	 rt_check(struct rtentry **, struct rtentry **, struct sockaddr *);
363 
364 #include <sys/eventhandler.h>
365 typedef void (*rtevent_arp_update_fn)(void *, struct rtentry *, uint8_t *, struct sockaddr *);
366 typedef void (*rtevent_redirect_fn)(void *, struct rtentry *, struct rtentry *, struct sockaddr *);
367 EVENTHANDLER_DECLARE(route_arp_update_event, rtevent_arp_update_fn);
368 EVENTHANDLER_DECLARE(route_redirect_event, rtevent_redirect_fn);
369 #endif
370 
371 #endif
372