1 /*-
2 * Copyright (c) 2014, 2018 Andrey V. Elsukov <ae@FreeBSD.org>
3 * All rights reserved.
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 *
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 ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD: releng/12.0/sys/netinet6/ip6_gre.c 336676 2018-07-24 16:35:52Z andrew $");
29
30 #include "opt_inet.h"
31 #include "opt_inet6.h"
32
33 #include <sys/param.h>
34 #include <sys/jail.h>
35 #include <sys/systm.h>
36 #include <sys/socket.h>
37 #include <sys/sockio.h>
38 #include <sys/mbuf.h>
39 #include <sys/errno.h>
40 #include <sys/kernel.h>
41 #include <sys/sysctl.h>
42 #include <sys/malloc.h>
43 #include <sys/proc.h>
44
45 #include <net/if.h>
46 #include <net/if_var.h>
47 #include <net/vnet.h>
48
49 #include <netinet/in.h>
50 #ifdef INET
51 #include <net/ethernet.h>
52 #include <netinet/ip.h>
53 #endif
54 #include <netinet/ip_encap.h>
55 #include <netinet/ip6.h>
56 #include <netinet6/ip6_var.h>
57 #include <netinet6/in6_var.h>
58 #include <netinet6/scope6_var.h>
59 #include <net/if_gre.h>
60
61 VNET_DEFINE(int, ip6_gre_hlim) = IPV6_DEFHLIM;
62 #define V_ip6_gre_hlim VNET(ip6_gre_hlim)
63
64 SYSCTL_DECL(_net_inet6_ip6);
65 SYSCTL_INT(_net_inet6_ip6, OID_AUTO, grehlim, CTLFLAG_VNET | CTLFLAG_RW,
66 &VNET_NAME(ip6_gre_hlim), 0, "Default hop limit for encapsulated packets");
67
68 VNET_DEFINE_STATIC(struct gre_list *, ipv6_hashtbl) = NULL;
69 #define V_ipv6_hashtbl VNET(ipv6_hashtbl)
70 #define GRE_HASH(src, dst) (V_ipv6_hashtbl[\
71 in6_gre_hashval((src), (dst)) & (GRE_HASH_SIZE - 1)])
72 #define GRE_HASH_SC(sc) GRE_HASH(&(sc)->gre_oip6.ip6_src,\
73 &(sc)->gre_oip6.ip6_dst)
74
75 static uint32_t
76 in6_gre_hashval(const struct in6_addr *src, const struct in6_addr *dst)
77 {
78 uint32_t ret;
79
80 ret = fnv_32_buf(src, sizeof(*src), FNV1_32_INIT);
81 return (fnv_32_buf(dst, sizeof(*dst), ret));
82 }
83
84 static int
85 in6_gre_checkdup(const struct gre_softc *sc, const struct in6_addr *src,
86 const struct in6_addr *dst)
87 {
88 struct gre_softc *tmp;
89
90 if (sc->gre_family == AF_INET6 &&
91 IN6_ARE_ADDR_EQUAL(&sc->gre_oip6.ip6_src, src) &&
92 IN6_ARE_ADDR_EQUAL(&sc->gre_oip6.ip6_dst, dst))
93 return (EEXIST);
94
95 CK_LIST_FOREACH(tmp, &GRE_HASH(src, dst), chain) {
96 if (tmp == sc)
97 continue;
98 if (IN6_ARE_ADDR_EQUAL(&tmp->gre_oip6.ip6_src, src) &&
99 IN6_ARE_ADDR_EQUAL(&tmp->gre_oip6.ip6_dst, dst))
100 return (EADDRNOTAVAIL);
101 }
102 return (0);
103 }
104
105 static int
106 in6_gre_lookup(const struct mbuf *m, int off, int proto, void **arg)
107 {
108 const struct ip6_hdr *ip6;
109 struct gre_softc *sc;
110
111 if (V_ipv6_hashtbl == NULL)
112 return (0);
113
114 MPASS(in_epoch(net_epoch_preempt));
115 ip6 = mtod(m, const struct ip6_hdr *);
116 CK_LIST_FOREACH(sc, &GRE_HASH(&ip6->ip6_dst, &ip6->ip6_src), chain) {
117 /*
118 * This is an inbound packet, its ip6_dst is source address
119 * in softc.
120 */
121 if (IN6_ARE_ADDR_EQUAL(&sc->gre_oip6.ip6_src,
122 &ip6->ip6_dst) &&
123 IN6_ARE_ADDR_EQUAL(&sc->gre_oip6.ip6_dst,
124 &ip6->ip6_src)) {
125 if ((GRE2IFP(sc)->if_flags & IFF_UP) == 0)
126 return (0);
127 *arg = sc;
128 return (ENCAP_DRV_LOOKUP);
129 }
130 }
131 return (0);
132 }
133
134 static void
135 in6_gre_attach(struct gre_softc *sc)
136 {
137
138 sc->gre_hlen = sizeof(struct greip6);
139 sc->gre_oip6.ip6_vfc = IPV6_VERSION;
140 sc->gre_oip6.ip6_nxt = IPPROTO_GRE;
141 gre_updatehdr(sc, &sc->gre_gi6hdr->gi6_gre);
142 CK_LIST_INSERT_HEAD(&GRE_HASH_SC(sc), sc, chain);
143 }
144
145 void
146 in6_gre_setopts(struct gre_softc *sc, u_long cmd, uint32_t value)
147 {
148
149 MPASS(cmd == GRESKEY || cmd == GRESOPTS);
150
151 /* NOTE: we are protected with gre_ioctl_sx lock */
152 MPASS(sc->gre_family == AF_INET6);
153 CK_LIST_REMOVE(sc, chain);
154 GRE_WAIT();
155 if (cmd == GRESKEY)
156 sc->gre_key = value;
157 else
158 sc->gre_options = value;
159 in6_gre_attach(sc);
160 }
161
162 int
163 in6_gre_ioctl(struct gre_softc *sc, u_long cmd, caddr_t data)
164 {
165 struct in6_ifreq *ifr = (struct in6_ifreq *)data;
166 struct sockaddr_in6 *dst, *src;
167 struct ip6_hdr *ip6;
168 int error;
169
170 /* NOTE: we are protected with gre_ioctl_sx lock */
171 error = EINVAL;
172 switch (cmd) {
173 case SIOCSIFPHYADDR_IN6:
174 src = &((struct in6_aliasreq *)data)->ifra_addr;
175 dst = &((struct in6_aliasreq *)data)->ifra_dstaddr;
176
177 /* sanity checks */
178 if (src->sin6_family != dst->sin6_family ||
179 src->sin6_family != AF_INET6 ||
180 src->sin6_len != dst->sin6_len ||
181 src->sin6_len != sizeof(*src))
182 break;
183 if (IN6_IS_ADDR_UNSPECIFIED(&src->sin6_addr) ||
184 IN6_IS_ADDR_UNSPECIFIED(&dst->sin6_addr)) {
185 error = EADDRNOTAVAIL;
186 break;
187 }
188 /*
189 * Check validity of the scope zone ID of the
190 * addresses, and convert it into the kernel
191 * internal form if necessary.
192 */
193 if ((error = sa6_embedscope(src, 0)) != 0 ||
194 (error = sa6_embedscope(dst, 0)) != 0)
195 break;
196
197 if (V_ipv6_hashtbl == NULL)
198 V_ipv6_hashtbl = gre_hashinit();
199 error = in6_gre_checkdup(sc, &src->sin6_addr,
200 &dst->sin6_addr);
201 if (error == EADDRNOTAVAIL)
202 break;
203 if (error == EEXIST) {
204 /* Addresses are the same. Just return. */
205 error = 0;
206 break;
207 }
208 ip6 = malloc(sizeof(struct greip6) + 3 * sizeof(uint32_t),
209 M_GRE, M_WAITOK | M_ZERO);
210 ip6->ip6_src = src->sin6_addr;
211 ip6->ip6_dst = dst->sin6_addr;
212 if (sc->gre_family != 0) {
213 /* Detach existing tunnel first */
214 CK_LIST_REMOVE(sc, chain);
215 GRE_WAIT();
216 free(sc->gre_hdr, M_GRE);
217 /* XXX: should we notify about link state change? */
218 }
219 sc->gre_family = AF_INET6;
220 sc->gre_hdr = ip6;
221 sc->gre_oseq = 0;
222 sc->gre_iseq = UINT32_MAX;
223 in6_gre_attach(sc);
224 break;
225 case SIOCGIFPSRCADDR_IN6:
226 case SIOCGIFPDSTADDR_IN6:
227 if (sc->gre_family != AF_INET6) {
228 error = EADDRNOTAVAIL;
229 break;
230 }
231 src = (struct sockaddr_in6 *)&ifr->ifr_addr;
232 memset(src, 0, sizeof(*src));
233 src->sin6_family = AF_INET6;
234 src->sin6_len = sizeof(*src);
235 src->sin6_addr = (cmd == SIOCGIFPSRCADDR_IN6) ?
236 sc->gre_oip6.ip6_src: sc->gre_oip6.ip6_dst;
237 error = prison_if(curthread->td_ucred, (struct sockaddr *)src);
238 if (error == 0)
239 error = sa6_recoverscope(src);
240 if (error != 0)
241 memset(src, 0, sizeof(*src));
242 break;
243 }
244 return (error);
245 }
246
247 int
248 in6_gre_output(struct mbuf *m, int af __unused, int hlen __unused)
249 {
250 struct greip6 *gi6;
251
252 gi6 = mtod(m, struct greip6 *);
253 gi6->gi6_ip6.ip6_hlim = V_ip6_gre_hlim;
254 return (ip6_output(m, NULL, NULL, IPV6_MINMTU, NULL, NULL, NULL));
255 }
256
257 static const struct encaptab *ecookie = NULL;
258 static const struct encap_config ipv6_encap_cfg = {
259 .proto = IPPROTO_GRE,
260 .min_length = sizeof(struct greip6) +
261 #ifdef INET
262 sizeof(struct ip),
263 #else
264 sizeof(struct ip6_hdr),
265 #endif
266 .exact_match = ENCAP_DRV_LOOKUP,
267 .lookup = in6_gre_lookup,
268 .input = gre_input
269 };
270
271 void
272 in6_gre_init(void)
273 {
274
275 if (!IS_DEFAULT_VNET(curvnet))
276 return;
277 ecookie = ip6_encap_attach(&ipv6_encap_cfg, NULL, M_WAITOK);
278 }
279
280 void
281 in6_gre_uninit(void)
282 {
283
284 if (IS_DEFAULT_VNET(curvnet))
285 ip6_encap_detach(ecookie);
286 if (V_ipv6_hashtbl != NULL)
287 gre_hashdestroy(V_ipv6_hashtbl);
288 }
Cache object: d3840a3c81b36a8e0cb12369cf021da8
|