xref: /freebsd/sys/net/route/route_helpers.c (revision 682b902daf3a3c5b62edb1509b847cd829abb4bd)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2020 Alexander V. Chernikov
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
30 #include "opt_inet.h"
31 #include "opt_inet6.h"
32 #include "opt_route.h"
33 
34 #include <sys/param.h>
35 #include <sys/jail.h>
36 #include <sys/systm.h>
37 #include <sys/malloc.h>
38 #include <sys/mbuf.h>
39 #include <sys/socket.h>
40 #include <sys/sysctl.h>
41 #include <sys/syslog.h>
42 #include <sys/sysproto.h>
43 #include <sys/proc.h>
44 #include <sys/domain.h>
45 #include <sys/kernel.h>
46 #include <sys/lock.h>
47 #include <sys/rmlock.h>
48 
49 #include <net/if.h>
50 #include <net/if_var.h>
51 #include <net/if_dl.h>
52 #include <net/route.h>
53 #include <net/route/route_var.h>
54 #include <net/route/nhop_utils.h>
55 #include <net/route/nhop.h>
56 #include <net/route/nhop_var.h>
57 #include <net/route/shared.h>
58 #ifdef INET
59 #include <netinet/in_fib.h>
60 #endif
61 #ifdef INET6
62 #include <netinet6/in6_fib.h>
63 #endif
64 #include <net/vnet.h>
65 
66 /*
67  * RIB helper functions.
68  */
69 
70 /*
71  * Calls @wa_f with @arg for each entry in the table specified by
72  * @af and @fibnum.
73  *
74  * Table is traversed under read lock.
75  */
76 void
77 rib_walk(int af, u_int fibnum, rt_walktree_f_t *wa_f, void *arg)
78 {
79 	RIB_RLOCK_TRACKER;
80 	struct rib_head *rnh;
81 
82 	if ((rnh = rt_tables_get_rnh(fibnum, af)) == NULL)
83 		return;
84 
85 	RIB_RLOCK(rnh);
86 	rnh->rnh_walktree(&rnh->head, (walktree_f_t *)wa_f, arg);
87 	RIB_RUNLOCK(rnh);
88 }
89 
90 /*
91  * Wrapper for the control plane functions for performing af-agnostic
92  *  lookups.
93  * @fibnum: fib to perform the lookup.
94  * @dst: sockaddr with family and addr filled in. IPv6 addresses needs to be in
95  *  deembedded from.
96  * @flags: fib(9) flags.
97  * @flowid: flow id for path selection in multipath use case.
98  *
99  * Returns nhop_object or NULL.
100  *
101  * Requires NET_EPOCH.
102  *
103  */
104 struct nhop_object *
105 rib_lookup(uint32_t fibnum, const struct sockaddr *dst, uint32_t flags,
106     uint32_t flowid)
107 {
108 	struct nhop_object *nh;
109 
110 	nh = NULL;
111 
112 	switch (dst->sa_family) {
113 #ifdef INET
114 	case AF_INET:
115 	{
116 		const struct sockaddr_in *a = (const struct sockaddr_in *)dst;
117 		nh = fib4_lookup(fibnum, a->sin_addr, 0, flags, flowid);
118 		break;
119 	}
120 #endif
121 #ifdef INET6
122 	case AF_INET6:
123 	{
124 		const struct sockaddr_in6 *a = (const struct sockaddr_in6*)dst;
125 		nh = fib6_lookup(fibnum, &a->sin6_addr, a->sin6_scope_id,
126 		    flags, flowid);
127 		break;
128 	}
129 #endif
130 	}
131 
132 	return (nh);
133 }
134 
135