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_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#define	ifatoia6(ifa)	((struct in6_ifaddr *)(ifa))
79
80CHK_STRUCT_ROUTE_COMPAT(struct route_in6, ro_dst);
81
82/*
83 * Gets real interface for the @rte.
84 * Returns rt_ifp for !IFF_LOOPBACK routers.
85 * Extracts "real" address interface from interface address
86 * loopback routes.
87 */
88static struct ifnet *
89fib6_get_ifaifp(struct rtentry *rte)
90{
91	struct ifnet *ifp;
92	struct sockaddr_dl *sdl;
93
94	ifp = rte->rt_ifp;
95	if ((ifp->if_flags & IFF_LOOPBACK) &&
96	    rte->rt_gateway->sa_family == AF_LINK) {
97		sdl = (struct sockaddr_dl *)rte->rt_gateway;
98		return (ifnet_byindex(sdl->sdl_index));
99	}
100
101	return (ifp);
102}
103
104static void
105fib6_rte_to_nh_basic(struct rtentry *rte, const struct in6_addr *dst,
106    uint32_t flags, struct nhop6_basic *pnh6)
107{
108	struct sockaddr_in6 *gw;
109
110	/* Do explicit nexthop zero unless we're copying it */
111	memset(pnh6, 0, sizeof(*pnh6));
112
113	if ((flags & NHR_IFAIF) != 0)
114		pnh6->nh_ifp = fib6_get_ifaifp(rte);
115	else
116		pnh6->nh_ifp = rte->rt_ifp;
117
118	pnh6->nh_mtu = min(rte->rt_mtu, IN6_LINKMTU(rte->rt_ifp));
119	if (rte->rt_flags & RTF_GATEWAY) {
120		/* Return address with embedded scope. */
121		gw = (struct sockaddr_in6 *)rte->rt_gateway;
122		pnh6->nh_addr = gw->sin6_addr;
123	} else
124		pnh6->nh_addr = *dst;
125	/* Set flags */
126	pnh6->nh_flags = fib_rte_to_nh_flags(rte->rt_flags);
127	gw = (struct sockaddr_in6 *)rt_key(rte);
128	if (IN6_IS_ADDR_UNSPECIFIED(&gw->sin6_addr))
129		pnh6->nh_flags |= NHF_DEFAULT;
130}
131
132static void
133fib6_rte_to_nh_extended(struct rtentry *rte, const struct in6_addr *dst,
134    uint32_t flags, struct nhop6_extended *pnh6)
135{
136	struct sockaddr_in6 *gw;
137
138	/* Do explicit nexthop zero unless we're copying it */
139	memset(pnh6, 0, sizeof(*pnh6));
140
141	if ((flags & NHR_IFAIF) != 0)
142		pnh6->nh_ifp = fib6_get_ifaifp(rte);
143	else
144		pnh6->nh_ifp = rte->rt_ifp;
145
146	pnh6->nh_mtu = min(rte->rt_mtu, IN6_LINKMTU(rte->rt_ifp));
147	if (rte->rt_flags & RTF_GATEWAY) {
148		/* Return address with embedded scope. */
149		gw = (struct sockaddr_in6 *)rte->rt_gateway;
150		pnh6->nh_addr = gw->sin6_addr;
151	} else
152		pnh6->nh_addr = *dst;
153	/* Set flags */
154	pnh6->nh_flags = fib_rte_to_nh_flags(rte->rt_flags);
155	gw = (struct sockaddr_in6 *)rt_key(rte);
156	if (IN6_IS_ADDR_UNSPECIFIED(&gw->sin6_addr))
157		pnh6->nh_flags |= NHF_DEFAULT;
158	pnh6->nh_ia = ifatoia6(rte->rt_ifa);
159}
160
161/*
162 * Performs IPv6 route table lookup on @dst. Returns 0 on success.
163 * Stores basic nexthop info into provided @pnh6 structure.
164 * Note that
165 * - nh_ifp represents logical transmit interface (rt_ifp) by default
166 * - nh_ifp represents "address" interface if NHR_IFAIF flag is passed
167 * - mtu from logical transmit interface will be returned.
168 * - nh_ifp cannot be safely dereferenced
169 * - nh_ifp represents rt_ifp (e.g. if looking up address on
170 *   interface "ix0" pointer to "ix0" interface will be returned instead
171 *   of "lo0")
172 * - howewer mtu from "transmit" interface will be returned.
173 * - scope will be embedded in nh_addr
174 */
175int
176fib6_lookup_nh_basic(uint32_t fibnum, const struct in6_addr *dst, uint32_t scopeid,
177    uint32_t flags, uint32_t flowid, struct nhop6_basic *pnh6)
178{
179	RIB_RLOCK_TRACKER;
180	struct rib_head *rh;
181	struct radix_node *rn;
182	struct sockaddr_in6 sin6;
183	struct rtentry *rte;
184
185	KASSERT((fibnum < rt_numfibs), ("fib6_lookup_nh_basic: bad fibnum"));
186	rh = rt_tables_get_rnh(fibnum, AF_INET6);
187	if (rh == NULL)
188		return (ENOENT);
189
190	/* Prepare lookup key */
191	memset(&sin6, 0, sizeof(sin6));
192	sin6.sin6_addr = *dst;
193	sin6.sin6_len = sizeof(struct sockaddr_in6);
194	/* Assume scopeid is valid and embed it directly */
195	if (IN6_IS_SCOPE_LINKLOCAL(dst))
196		sin6.sin6_addr.s6_addr16[1] = htons(scopeid & 0xffff);
197
198	RIB_RLOCK(rh);
199	rn = rh->rnh_matchaddr((void *)&sin6, &rh->head);
200	if (rn != NULL && ((rn->rn_flags & RNF_ROOT) == 0)) {
201		rte = RNTORT(rn);
202		/* Ensure route & ifp is UP */
203		if (RT_LINK_IS_UP(rte->rt_ifp)) {
204			fib6_rte_to_nh_basic(rte, &sin6.sin6_addr, flags, pnh6);
205			RIB_RUNLOCK(rh);
206			return (0);
207		}
208	}
209	RIB_RUNLOCK(rh);
210
211	return (ENOENT);
212}
213
214/*
215 * Performs IPv6 route table lookup on @dst. Returns 0 on success.
216 * Stores extended nexthop info into provided @pnh6 structure.
217 * Note that
218 * - nh_ifp cannot be safely dereferenced unless NHR_REF is specified.
219 * - in that case you need to call fib6_free_nh_ext()
220 * - nh_ifp represents logical transmit interface (rt_ifp) by default
221 * - nh_ifp represents "address" interface if NHR_IFAIF flag is passed
222 * - mtu from logical transmit interface will be returned.
223 * - scope will be embedded in nh_addr
224 */
225int
226fib6_lookup_nh_ext(uint32_t fibnum, const struct in6_addr *dst,uint32_t scopeid,
227    uint32_t flags, uint32_t flowid, struct nhop6_extended *pnh6)
228{
229	RIB_RLOCK_TRACKER;
230	struct rib_head *rh;
231	struct radix_node *rn;
232	struct sockaddr_in6 sin6;
233	struct rtentry *rte;
234
235	KASSERT((fibnum < rt_numfibs), ("fib6_lookup_nh_ext: bad fibnum"));
236	rh = rt_tables_get_rnh(fibnum, AF_INET6);
237	if (rh == NULL)
238		return (ENOENT);
239
240	/* Prepare lookup key */
241	memset(&sin6, 0, sizeof(sin6));
242	sin6.sin6_len = sizeof(struct sockaddr_in6);
243	sin6.sin6_addr = *dst;
244	/* Assume scopeid is valid and embed it directly */
245	if (IN6_IS_SCOPE_LINKLOCAL(dst))
246		sin6.sin6_addr.s6_addr16[1] = htons(scopeid & 0xffff);
247
248	RIB_RLOCK(rh);
249	rn = rh->rnh_matchaddr((void *)&sin6, &rh->head);
250	if (rn != NULL && ((rn->rn_flags & RNF_ROOT) == 0)) {
251		rte = RNTORT(rn);
252#ifdef RADIX_MPATH
253		rte = rt_mpath_select(rte, flowid);
254		if (rte == NULL) {
255			RIB_RUNLOCK(rh);
256			return (ENOENT);
257		}
258#endif
259		/* Ensure route & ifp is UP */
260		if (RT_LINK_IS_UP(rte->rt_ifp)) {
261			fib6_rte_to_nh_extended(rte, &sin6.sin6_addr, flags,
262			    pnh6);
263			if ((flags & NHR_REF) != 0) {
264				/* TODO: Do lwref on egress ifp's */
265			}
266			RIB_RUNLOCK(rh);
267
268			return (0);
269		}
270	}
271	RIB_RUNLOCK(rh);
272
273	return (ENOENT);
274}
275
276void
277fib6_free_nh_ext(uint32_t fibnum, struct nhop6_extended *pnh6)
278{
279
280}
281
282#endif
283
284