xref: /freebsd/sys/net/route.h (revision ca9ac06c99bfd0150b85d4d83c396ce6237c0e05)
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 /*
173  * Routing statistics.
174  */
175 struct	rtstat {
176 	short	rts_badredirect;	/* bogus redirect calls */
177 	short	rts_dynamic;		/* routes created by redirects */
178 	short	rts_newgateway;		/* routes modified by redirects */
179 	short	rts_unreach;		/* lookups which failed */
180 	short	rts_wildcard;		/* lookups satisfied by a wildcard */
181 };
182 /*
183  * Structures for routing messages.
184  */
185 struct rt_msghdr {
186 	u_short	rtm_msglen;	/* to skip over non-understood messages */
187 	u_char	rtm_version;	/* future binary compatibility */
188 	u_char	rtm_type;	/* message type */
189 	u_short	rtm_index;	/* index for associated ifp */
190 	int	rtm_flags;	/* flags, incl. kern & message, e.g. DONE */
191 	int	rtm_addrs;	/* bitmask identifying sockaddrs in msg */
192 	pid_t	rtm_pid;	/* identify sender */
193 	int	rtm_seq;	/* for sender to identify action */
194 	int	rtm_errno;	/* why failed */
195 	int	rtm_use;	/* from rtentry */
196 	u_long	rtm_inits;	/* which metrics we are initializing */
197 	struct	rt_metrics rtm_rmx; /* metrics themselves */
198 };
199 
200 #define RTM_VERSION	5	/* Up the ante and ignore older versions */
201 
202 /*
203  * Message types.
204  */
205 #define RTM_ADD		0x1	/* Add Route */
206 #define RTM_DELETE	0x2	/* Delete Route */
207 #define RTM_CHANGE	0x3	/* Change Metrics or flags */
208 #define RTM_GET		0x4	/* Report Metrics */
209 #define RTM_LOSING	0x5	/* Kernel Suspects Partitioning */
210 #define RTM_REDIRECT	0x6	/* Told to use different route */
211 #define RTM_MISS	0x7	/* Lookup failed on this address */
212 #define RTM_LOCK	0x8	/* fix specified metrics */
213 #define RTM_OLDADD	0x9	/* caused by SIOCADDRT */
214 #define RTM_OLDDEL	0xa	/* caused by SIOCDELRT */
215 #define RTM_RESOLVE	0xb	/* req to resolve dst to LL addr */
216 #define RTM_NEWADDR	0xc	/* address being added to iface */
217 #define RTM_DELADDR	0xd	/* address being removed from iface */
218 #define RTM_IFINFO	0xe	/* iface going up/down etc. */
219 #define	RTM_NEWMADDR	0xf	/* mcast group membership being added to if */
220 #define	RTM_DELMADDR	0x10	/* mcast group membership being deleted */
221 #define	RTM_IFANNOUNCE	0x11	/* iface arrival/departure */
222 #define	RTM_IEEE80211	0x12	/* IEEE80211 wireless event */
223 
224 /*
225  * Bitmask values for rtm_inits and rmx_locks.
226  */
227 #define RTV_MTU		0x1	/* init or lock _mtu */
228 #define RTV_HOPCOUNT	0x2	/* init or lock _hopcount */
229 #define RTV_EXPIRE	0x4	/* init or lock _expire */
230 #define RTV_RPIPE	0x8	/* init or lock _recvpipe */
231 #define RTV_SPIPE	0x10	/* init or lock _sendpipe */
232 #define RTV_SSTHRESH	0x20	/* init or lock _ssthresh */
233 #define RTV_RTT		0x40	/* init or lock _rtt */
234 #define RTV_RTTVAR	0x80	/* init or lock _rttvar */
235 
236 /*
237  * Bitmask values for rtm_addrs.
238  */
239 #define RTA_DST		0x1	/* destination sockaddr present */
240 #define RTA_GATEWAY	0x2	/* gateway sockaddr present */
241 #define RTA_NETMASK	0x4	/* netmask sockaddr present */
242 #define RTA_GENMASK	0x8	/* cloning mask sockaddr present */
243 #define RTA_IFP		0x10	/* interface name sockaddr present */
244 #define RTA_IFA		0x20	/* interface addr sockaddr present */
245 #define RTA_AUTHOR	0x40	/* sockaddr for author of redirect */
246 #define RTA_BRD		0x80	/* for NEWADDR, broadcast or p-p dest addr */
247 
248 /*
249  * Index offsets for sockaddr array for alternate internal encoding.
250  */
251 #define RTAX_DST	0	/* destination sockaddr present */
252 #define RTAX_GATEWAY	1	/* gateway sockaddr present */
253 #define RTAX_NETMASK	2	/* netmask sockaddr present */
254 #define RTAX_GENMASK	3	/* cloning mask sockaddr present */
255 #define RTAX_IFP	4	/* interface name sockaddr present */
256 #define RTAX_IFA	5	/* interface addr sockaddr present */
257 #define RTAX_AUTHOR	6	/* sockaddr for author of redirect */
258 #define RTAX_BRD	7	/* for NEWADDR, broadcast or p-p dest addr */
259 #define RTAX_MAX	8	/* size of array to allocate */
260 
261 struct rt_addrinfo {
262 	int	rti_addrs;
263 	struct	sockaddr *rti_info[RTAX_MAX];
264 	int	rti_flags;
265 	struct	ifaddr *rti_ifa;
266 	struct	ifnet *rti_ifp;
267 };
268 
269 /*
270  * This macro returns the size of a struct sockaddr when passed
271  * through a routing socket. Basically we round up sa_len to
272  * a multiple of sizeof(long), with a minimum of sizeof(long).
273  * The check for a NULL pointer is just a convenience, probably never used.
274  * The case sa_len == 0 should only apply to empty structures.
275  */
276 #define SA_SIZE(sa)						\
277     (  (!(sa) || ((struct sockaddr *)(sa))->sa_len == 0) ?	\
278 	sizeof(long)		:				\
279 	1 + ( (((struct sockaddr *)(sa))->sa_len - 1) | (sizeof(long) - 1) ) )
280 
281 #ifdef _KERNEL
282 
283 #define	RT_LOCK_INIT(_rt) \
284 	mtx_init(&(_rt)->rt_mtx, "rtentry", NULL, MTX_DEF | MTX_DUPOK)
285 #define	RT_LOCK(_rt)		mtx_lock(&(_rt)->rt_mtx)
286 #define	RT_UNLOCK(_rt)		mtx_unlock(&(_rt)->rt_mtx)
287 #define	RT_LOCK_DESTROY(_rt)	mtx_destroy(&(_rt)->rt_mtx)
288 #define	RT_LOCK_ASSERT(_rt)	mtx_assert(&(_rt)->rt_mtx, MA_OWNED)
289 
290 #define	RT_ADDREF(_rt)	do {					\
291 	RT_LOCK_ASSERT(_rt);					\
292 	KASSERT((_rt)->rt_refcnt >= 0,				\
293 		("negative refcnt %ld", (_rt)->rt_refcnt));	\
294 	(_rt)->rt_refcnt++;					\
295 } while (0);
296 #define	RT_REMREF(_rt)	do {					\
297 	RT_LOCK_ASSERT(_rt);					\
298 	KASSERT((_rt)->rt_refcnt > 0,				\
299 		("bogus refcnt %ld", (_rt)->rt_refcnt));	\
300 	(_rt)->rt_refcnt--;					\
301 } while (0);
302 
303 #define	RTFREE_LOCKED(_rt) do {					\
304 		if ((_rt)->rt_refcnt <= 1)			\
305 			rtfree(_rt);				\
306 		else {						\
307 			RT_REMREF(_rt);				\
308 			RT_UNLOCK(_rt);				\
309 		}						\
310 		/* guard against invalid refs */		\
311 		_rt = 0;					\
312 	} while (0)
313 #define	RTFREE(_rt) do {					\
314 		RT_LOCK(_rt);					\
315 		RTFREE_LOCKED(_rt);				\
316 	} while (0)
317 
318 extern struct radix_node_head *rt_tables[AF_MAX+1];
319 
320 struct ifmultiaddr;
321 
322 int	 rt_getifa(struct rt_addrinfo *);
323 void	 rt_ieee80211msg(struct ifnet *, int, void *, size_t);
324 void	 rt_ifannouncemsg(struct ifnet *, int);
325 void	 rt_ifmsg(struct ifnet *);
326 void	 rt_missmsg(int, struct rt_addrinfo *, int, int);
327 void	 rt_newaddrmsg(int, struct ifaddr *, int, struct rtentry *);
328 void	 rt_newmaddrmsg(int, struct ifmultiaddr *);
329 int	 rt_setgate(struct rtentry *, struct sockaddr *, struct sockaddr *);
330 
331 /*
332  * Note the following locking behavior:
333  *
334  *    rtalloc_ign() and rtalloc() return ro->ro_rt unlocked
335  *
336  *    rtalloc1() returns a locked rtentry
337  *
338  *    rtfree() and RTFREE_LOCKED() require a locked rtentry
339  *
340  *    RTFREE() uses an unlocked entry.
341  */
342 
343 void	 rtalloc_ign(struct route *ro, u_long ignflags);
344 void	 rtalloc(struct route *ro); /* XXX deprecated, use rtalloc_ign(ro, 0) */
345 struct rtentry *rtalloc1(struct sockaddr *, int, u_long);
346 int	 rtexpunge(struct rtentry *);
347 void	 rtfree(struct rtentry *);
348 int	 rtinit(struct ifaddr *, int, int);
349 int	 rtioctl(u_long, caddr_t);
350 void	 rtredirect(struct sockaddr *, struct sockaddr *,
351 	    struct sockaddr *, int, struct sockaddr *);
352 int	 rtrequest(int, struct sockaddr *,
353 	    struct sockaddr *, struct sockaddr *, int, struct rtentry **);
354 int	 rtrequest1(int, struct rt_addrinfo *, struct rtentry **);
355 int	 rt_check(struct rtentry **, struct rtentry **, struct sockaddr *);
356 #endif
357 
358 #endif
359