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 * 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
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/rwlock.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_var.h>
53#include <net/vnet.h>
54
55#ifdef RADIX_MPATH
56#include <net/radix_mpath.h>
57#endif
58
59#include <netinet/in.h>
60#include <netinet/in_var.h>
61#include <netinet/ip_mroute.h>
62#include <netinet/ip6.h>
63#include <netinet6/in6_fib.h>
64#include <netinet6/in6_var.h>
65#include <netinet6/nd6.h>
66#include <netinet6/scope6_var.h>
67
68#include <net/if_types.h>
69
70#ifdef INET6
71static void fib6_rte_to_nh_extended(struct rtentry *rte,
72    const struct in6_addr *dst, uint32_t flags, struct nhop6_extended *pnh6);
73static void fib6_rte_to_nh_basic(struct rtentry *rte, const struct in6_addr *dst,
74    uint32_t flags, struct nhop6_basic *pnh6);
75static struct ifnet *fib6_get_ifaifp(struct rtentry *rte);
76#define RNTORT(p)	((struct rtentry *)(p))
77
78/*
79 * Gets real interface for the @rte.
80 * Returns rt_ifp for !IFF_LOOPBACK routers.
81 * Extracts "real" address interface from interface address
82 * loopback routes.
83 */
84static struct ifnet *
85fib6_get_ifaifp(struct rtentry *rte)
86{
87	struct ifnet *ifp;
88	struct sockaddr_dl *sdl;
89
90	ifp = rte->rt_ifp;
91	if ((ifp->if_flags & IFF_LOOPBACK) &&
92	    rte->rt_gateway->sa_family == AF_LINK) {
93		sdl = (struct sockaddr_dl *)rte->rt_gateway;
94		return (ifnet_byindex(sdl->sdl_index));
95	}
96
97	return (ifp);
98}
99
100static void
101fib6_rte_to_nh_basic(struct rtentry *rte, const struct in6_addr *dst,
102    uint32_t flags, struct nhop6_basic *pnh6)
103{
104	struct sockaddr_in6 *gw;
105
106	/* Do explicit nexthop zero unless we're copying it */
107	memset(pnh6, 0, sizeof(*pnh6));
108
109	if ((flags & NHR_IFAIF) != 0)
110		pnh6->nh_ifp = fib6_get_ifaifp(rte);
111	else
112		pnh6->nh_ifp = rte->rt_ifp;
113
114	pnh6->nh_mtu = min(rte->rt_mtu, IN6_LINKMTU(rte->rt_ifp));
115	if (rte->rt_flags & RTF_GATEWAY) {
116		gw = (struct sockaddr_in6 *)rte->rt_gateway;
117		pnh6->nh_addr = gw->sin6_addr;
118		in6_clearscope(&pnh6->nh_addr);
119	} else
120		pnh6->nh_addr = *dst;
121	/* Set flags */
122	pnh6->nh_flags = fib_rte_to_nh_flags(rte->rt_flags);
123	gw = (struct sockaddr_in6 *)rt_key(rte);
124	if (IN6_IS_ADDR_UNSPECIFIED(&gw->sin6_addr))
125		pnh6->nh_flags |= NHF_DEFAULT;
126}
127
128static void
129fib6_rte_to_nh_extended(struct rtentry *rte, const struct in6_addr *dst,
130    uint32_t flags, struct nhop6_extended *pnh6)
131{
132	struct sockaddr_in6 *gw;
133
134	/* Do explicit nexthop zero unless we're copying it */
135	memset(pnh6, 0, sizeof(*pnh6));
136
137	if ((flags & NHR_IFAIF) != 0)
138		pnh6->nh_ifp = fib6_get_ifaifp(rte);
139	else
140		pnh6->nh_ifp = rte->rt_ifp;
141
142	pnh6->nh_mtu = min(rte->rt_mtu, IN6_LINKMTU(rte->rt_ifp));
143	if (rte->rt_flags & RTF_GATEWAY) {
144		gw = (struct sockaddr_in6 *)rte->rt_gateway;
145		pnh6->nh_addr = gw->sin6_addr;
146		in6_clearscope(&pnh6->nh_addr);
147	} else
148		pnh6->nh_addr = *dst;
149	/* Set flags */
150	pnh6->nh_flags = fib_rte_to_nh_flags(rte->rt_flags);
151	gw = (struct sockaddr_in6 *)rt_key(rte);
152	if (IN6_IS_ADDR_UNSPECIFIED(&gw->sin6_addr))
153		pnh6->nh_flags |= NHF_DEFAULT;
154}
155
156/*
157 * Performs IPv6 route table lookup on @dst. Returns 0 on success.
158 * Stores basic nexthop info into provided @pnh6 structure.
159 * Note that
160 * - nh_ifp represents logical transmit interface (rt_ifp) by default
161 * - nh_ifp represents "address" interface if NHR_IFAIF flag is passed
162 * - mtu from logical transmit interface will be returned.
163 * - nh_ifp cannot be safely dereferenced
164 * - nh_ifp represents rt_ifp (e.g. if looking up address on
165 *   interface "ix0" pointer to "ix0" interface will be returned instead
166 *   of "lo0")
167 * - howewer mtu from "transmit" interface will be returned.
168 * - scope will be embedded in nh_addr
169 */
170int
171fib6_lookup_nh_basic(uint32_t fibnum, const struct in6_addr *dst, uint32_t scopeid,
172    uint32_t flags, uint32_t flowid, struct nhop6_basic *pnh6)
173{
174	struct rib_head *rh;
175	struct radix_node *rn;
176	struct sockaddr_in6 sin6;
177	struct rtentry *rte;
178
179	KASSERT((fibnum < rt_numfibs), ("fib6_lookup_nh_basic: bad fibnum"));
180	rh = rt_tables_get_rnh(fibnum, AF_INET6);
181	if (rh == NULL)
182		return (ENOENT);
183
184	/* Prepare lookup key */
185	memset(&sin6, 0, sizeof(sin6));
186	sin6.sin6_addr = *dst;
187	sin6.sin6_len = sizeof(struct sockaddr_in6);
188	/* Assume scopeid is valid and embed it directly */
189	if (IN6_IS_SCOPE_LINKLOCAL(dst))
190		sin6.sin6_addr.s6_addr16[1] = htons(scopeid & 0xffff);
191
192	RIB_RLOCK(rh);
193	rn = rh->rnh_matchaddr((void *)&sin6, &rh->head);
194	if (rn != NULL && ((rn->rn_flags & RNF_ROOT) == 0)) {
195		rte = RNTORT(rn);
196		/* Ensure route & ifp is UP */
197		if (RT_LINK_IS_UP(rte->rt_ifp)) {
198			fib6_rte_to_nh_basic(rte, &sin6.sin6_addr, flags, pnh6);
199			RIB_RUNLOCK(rh);
200			return (0);
201		}
202	}
203	RIB_RUNLOCK(rh);
204
205	return (ENOENT);
206}
207
208/*
209 * Performs IPv6 route table lookup on @dst. Returns 0 on success.
210 * Stores extended nexthop info into provided @pnh6 structure.
211 * Note that
212 * - nh_ifp cannot be safely dereferenced unless NHR_REF is specified.
213 * - in that case you need to call fib6_free_nh_ext()
214 * - nh_ifp represents logical transmit interface (rt_ifp) by default
215 * - nh_ifp represents "address" interface if NHR_IFAIF flag is passed
216 * - mtu from logical transmit interface will be returned.
217 * - scope will be embedded in nh_addr
218 */
219int
220fib6_lookup_nh_ext(uint32_t fibnum, const struct in6_addr *dst,uint32_t scopeid,
221    uint32_t flags, uint32_t flowid, struct nhop6_extended *pnh6)
222{
223	struct rib_head *rh;
224	struct radix_node *rn;
225	struct sockaddr_in6 sin6;
226	struct rtentry *rte;
227
228	KASSERT((fibnum < rt_numfibs), ("fib6_lookup_nh_ext: bad fibnum"));
229	rh = rt_tables_get_rnh(fibnum, AF_INET6);
230	if (rh == NULL)
231		return (ENOENT);
232
233	/* Prepare lookup key */
234	memset(&sin6, 0, sizeof(sin6));
235	sin6.sin6_len = sizeof(struct sockaddr_in6);
236	sin6.sin6_addr = *dst;
237	/* Assume scopeid is valid and embed it directly */
238	if (IN6_IS_SCOPE_LINKLOCAL(dst))
239		sin6.sin6_addr.s6_addr16[1] = htons(scopeid & 0xffff);
240
241	RIB_RLOCK(rh);
242	rn = rh->rnh_matchaddr((void *)&sin6, &rh->head);
243	if (rn != NULL && ((rn->rn_flags & RNF_ROOT) == 0)) {
244		rte = RNTORT(rn);
245#ifdef RADIX_MPATH
246		rte = rt_mpath_select(rte, flowid);
247		if (rte == NULL) {
248			RIB_RUNLOCK(rh);
249			return (ENOENT);
250		}
251#endif
252		/* Ensure route & ifp is UP */
253		if (RT_LINK_IS_UP(rte->rt_ifp)) {
254			fib6_rte_to_nh_extended(rte, &sin6.sin6_addr, flags,
255			    pnh6);
256			if ((flags & NHR_REF) != 0) {
257				/* TODO: Do lwref on egress ifp's */
258			}
259			RIB_RUNLOCK(rh);
260
261			return (0);
262		}
263	}
264	RIB_RUNLOCK(rh);
265
266	return (ENOENT);
267}
268
269void
270fib6_free_nh_ext(uint32_t fibnum, struct nhop6_extended *pnh6)
271{
272
273}
274
275#endif
276
277