xref: /csrg-svn/sys/net/route.h (revision 23164)
1 /*
2  * Copyright (c) 1980 Regents of the University of California.
3  * All rights reserved.  The Berkeley software License Agreement
4  * specifies the terms and conditions for redistribution.
5  *
6  *	@(#)route.h	6.4 (Berkeley) 06/08/85
7  */
8 
9 /*
10  * Kernel resident routing tables.
11  *
12  * The routing tables are initialized at boot time by
13  * making entries for all directly connected interfaces.
14  */
15 
16 /*
17  * A route consists of a destination address and a reference
18  * to a routing entry.  These are often held by protocols
19  * in their control blocks, e.g. inpcb.
20  */
21 struct route {
22 	struct	rtentry *ro_rt;
23 	struct	sockaddr ro_dst;
24 #ifdef notdef
25 	caddr_t	ro_pcb;			/* not used yet */
26 #endif
27 };
28 
29 /*
30  * We distinguish between routes to hosts and routes to networks,
31  * preferring the former if available.  For each route we infer
32  * the interface to use from the gateway address supplied when
33  * the route was entered.  Routes that forward packets through
34  * gateways are marked so that the output routines know to address the
35  * gateway rather than the ultimate destination.
36  */
37 struct rtentry {
38 	u_long	rt_hash;		/* to speed lookups */
39 	struct	sockaddr rt_dst;	/* key */
40 	struct	sockaddr rt_gateway;	/* value */
41 	short	rt_flags;		/* up/down?, host/net */
42 	short	rt_refcnt;		/* # held references */
43 	u_long	rt_use;			/* raw # packets forwarded */
44 	struct	ifnet *rt_ifp;		/* the answer: interface to use */
45 };
46 
47 #define	RTF_UP		0x1		/* route useable */
48 #define	RTF_GATEWAY	0x2		/* destination is a gateway */
49 #define	RTF_HOST	0x4		/* host entry (net otherwise) */
50 
51 /*
52  * Routing statistics.
53  */
54 struct	rtstat {
55 	short	rts_badredirect;	/* bogus redirect calls */
56 	short	rts_dynamic;		/* routes created by redirects */
57 	short	rts_newgateway;		/* routes modified by redirects */
58 	short	rts_unreach;		/* lookups which failed */
59 	short	rts_wildcard;		/* lookups satisfied by a wildcard */
60 };
61 
62 #ifdef KERNEL
63 #define	RTFREE(rt) \
64 	if ((rt)->rt_refcnt == 1) \
65 		rtfree(rt); \
66 	else \
67 		(rt)->rt_refcnt--;
68 
69 #ifdef	GATEWAY
70 #define	RTHASHSIZ	64
71 #else
72 #define	RTHASHSIZ	8
73 #endif
74 #if	(RTHASHSIZ & (RTHASHSIZ - 1)) == 0
75 #define RTHASHMOD(h)	((h) & (RTHASHSIZ - 1))
76 #else
77 #define RTHASHMOD(h)	((h) % RTHASHSIZ)
78 #endif
79 struct	mbuf *rthost[RTHASHSIZ];
80 struct	mbuf *rtnet[RTHASHSIZ];
81 struct	rtstat	rtstat;
82 #endif
83