1/*-
2 * Copyright (c) 2015
3 * 	Alexander V. Chernikov <melifaro@FreeBSD.org>
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 * 3. 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
30#include <sys/cdefs.h>
31__FBSDID("$FreeBSD$");
32
33#include "opt_inet.h"
34#include "opt_inet6.h"
35#include "opt_route.h"
36#include "opt_mpath.h"
37
38#include <sys/param.h>
39#include <sys/systm.h>
40#include <sys/lock.h>
41#include <sys/rmlock.h>
42#include <sys/malloc.h>
43#include <sys/mbuf.h>
44#include <sys/socket.h>
45#include <sys/sysctl.h>
46#include <sys/kernel.h>
47
48#include <net/if.h>
49#include <net/if_var.h>
50#include <net/if_dl.h>
51#include <net/route.h>
52#include <net/route/route_var.h>
53#include <net/route/nhop.h>
54#include <net/vnet.h>
55
56#ifdef RADIX_MPATH
57#include <net/radix_mpath.h>
58#endif
59
60#include <netinet/in.h>
61#include <netinet/in_var.h>
62#include <netinet/ip_mroute.h>
63#include <netinet/ip6.h>
64#include <netinet6/in6_fib.h>
65#include <netinet6/in6_var.h>
66#include <netinet6/nd6.h>
67#include <netinet6/scope6_var.h>
68
69#include <net/if_types.h>
70
71#ifdef INET6
72
73CHK_STRUCT_ROUTE_COMPAT(struct route_in6, ro_dst);
74
75/*
76 * Looks up path in fib @fibnum specified by @dst.
77 * Assumes scope is deembedded and provided in @scopeid.
78 *
79 * Returns path nexthop on success. Nexthop is safe to use
80 *  within the current network epoch. If longer lifetime is required,
81 *  one needs to pass NHR_REF as a flag. This will return referenced
82 *  nexthop.
83 */
84struct nhop_object *
85fib6_lookup(uint32_t fibnum, const struct in6_addr *dst6,
86    uint32_t scopeid, uint32_t flags, uint32_t flowid)
87{
88	RIB_RLOCK_TRACKER;
89	struct rib_head *rh;
90	struct radix_node *rn;
91	struct rtentry *rt;
92	struct nhop_object *nh;
93	struct sockaddr_in6 sin6;
94
95	KASSERT((fibnum < rt_numfibs), ("fib6_lookup: bad fibnum"));
96	rh = rt_tables_get_rnh(fibnum, AF_INET6);
97	if (rh == NULL)
98		return (NULL);
99
100	/* TODO: radix changes */
101	//addr = *dst6;
102	/* Prepare lookup key */
103	memset(&sin6, 0, sizeof(sin6));
104	sin6.sin6_len = sizeof(struct sockaddr_in6);
105	sin6.sin6_addr = *dst6;
106
107	/* Assume scopeid is valid and embed it directly */
108	if (IN6_IS_SCOPE_LINKLOCAL(dst6))
109		sin6.sin6_addr.s6_addr16[1] = htons(scopeid & 0xffff);
110
111	RIB_RLOCK(rh);
112	rn = rh->rnh_matchaddr((void *)&sin6, &rh->head);
113	if (rn != NULL && ((rn->rn_flags & RNF_ROOT) == 0)) {
114		rt = RNTORT(rn);
115#ifdef RADIX_MPATH
116		if (rt_mpath_next(rt) != NULL)
117			rt = rt_mpath_selectrte(rt, flowid);
118#endif
119		nh = rt->rt_nhop;
120		/* Ensure route & ifp is UP */
121		if (RT_LINK_IS_UP(nh->nh_ifp)) {
122			if (flags & NHR_REF)
123				nhop_ref_object(nh);
124			RIB_RUNLOCK(rh);
125			return (nh);
126		}
127	}
128	RIB_RUNLOCK(rh);
129
130	RTSTAT_INC(rts_unreach);
131	return (NULL);
132}
133
134inline static int
135check_urpf(const struct nhop_object *nh, uint32_t flags,
136    const struct ifnet *src_if)
137{
138
139	if (src_if != NULL && nh->nh_aifp == src_if) {
140		return (1);
141	}
142	if (src_if == NULL) {
143		if ((flags & NHR_NODEFAULT) == 0)
144			return (1);
145		else if ((nh->nh_flags & NHF_DEFAULT) == 0)
146			return (1);
147	}
148
149	return (0);
150}
151
152#ifdef RADIX_MPATH
153inline static int
154check_urpf_mpath(struct rtentry *rt, uint32_t flags,
155    const struct ifnet *src_if)
156{
157
158	while (rt != NULL) {
159		if (check_urpf(rt->rt_nhop, flags, src_if) != 0)
160			return (1);
161		rt = rt_mpath_next(rt);
162	}
163
164	return (0);
165}
166#endif
167
168/*
169 * Performs reverse path forwarding lookup.
170 * If @src_if is non-zero, verifies that at least 1 path goes via
171 *   this interface.
172 * If @src_if is zero, verifies that route exist.
173 * if @flags contains NHR_NOTDEFAULT, do not consider default route.
174 *
175 * Returns 1 if route matching conditions is found, 0 otherwise.
176 */
177int
178fib6_check_urpf(uint32_t fibnum, const struct in6_addr *dst6,
179    uint32_t scopeid, uint32_t flags, const struct ifnet *src_if)
180{
181	RIB_RLOCK_TRACKER;
182	struct rib_head *rh;
183	struct radix_node *rn;
184	struct rtentry *rt;
185	struct sockaddr_in6 sin6;
186	int ret;
187
188	KASSERT((fibnum < rt_numfibs), ("fib6_check_urpf: bad fibnum"));
189	rh = rt_tables_get_rnh(fibnum, AF_INET6);
190	if (rh == NULL)
191		return (0);
192
193	/* TODO: radix changes */
194	/* Prepare lookup key */
195	memset(&sin6, 0, sizeof(sin6));
196	sin6.sin6_len = sizeof(struct sockaddr_in6);
197	sin6.sin6_addr = *dst6;
198
199	/* Assume scopeid is valid and embed it directly */
200	if (IN6_IS_SCOPE_LINKLOCAL(dst6))
201		sin6.sin6_addr.s6_addr16[1] = htons(scopeid & 0xffff);
202
203	RIB_RLOCK(rh);
204	rn = rh->rnh_matchaddr((void *)&sin6, &rh->head);
205	if (rn != NULL && ((rn->rn_flags & RNF_ROOT) == 0)) {
206		rt = RNTORT(rn);
207#ifdef	RADIX_MPATH
208		ret = check_urpf_mpath(rt, flags, src_if);
209#else
210		ret = check_urpf(rt->rt_nhop, flags, src_if);
211#endif
212		RIB_RUNLOCK(rh);
213		return (ret);
214	}
215	RIB_RUNLOCK(rh);
216
217	return (0);
218}
219
220struct nhop_object *
221fib6_lookup_debugnet(uint32_t fibnum, const struct in6_addr *dst6,
222    uint32_t scopeid, uint32_t flags)
223{
224	struct rib_head *rh;
225	struct radix_node *rn;
226	struct rtentry *rt;
227	struct nhop_object *nh;
228	struct sockaddr_in6 sin6;
229
230	KASSERT((fibnum < rt_numfibs), ("fib6_lookup: bad fibnum"));
231	rh = rt_tables_get_rnh(fibnum, AF_INET6);
232	if (rh == NULL)
233		return (NULL);
234
235	/* TODO: radix changes */
236	//addr = *dst6;
237	/* Prepare lookup key */
238	memset(&sin6, 0, sizeof(sin6));
239	sin6.sin6_len = sizeof(struct sockaddr_in6);
240	sin6.sin6_addr = *dst6;
241
242	/* Assume scopeid is valid and embed it directly */
243	if (IN6_IS_SCOPE_LINKLOCAL(dst6))
244		sin6.sin6_addr.s6_addr16[1] = htons(scopeid & 0xffff);
245
246	rn = rh->rnh_matchaddr((void *)&sin6, &rh->head);
247	if (rn != NULL && ((rn->rn_flags & RNF_ROOT) == 0)) {
248		rt = RNTORT(rn);
249		nh = rt->rt_nhop;
250		/* Ensure route & ifp is UP */
251		if (RT_LINK_IS_UP(nh->nh_ifp)) {
252			if (flags & NHR_REF)
253				nhop_ref_object(nh);
254			return (nh);
255		}
256	}
257
258	return (NULL);
259}
260
261#endif
262