2 * SPDX-License-Identifier: BSD-2-Clause-NetBSD
4 * Copyright (c) 1998 The NetBSD Foundation, Inc.
5 * Copyright (c) 2014, 2018 Andrey V. Elsukov <ae@FreeBSD.org>
8 * This code is derived from software contributed to The NetBSD Foundation
9 * by Heiko W.Rupp <hwr@pilhuhn.de>
11 * IPv6-over-GRE contributed by Gert Doering <gert@greenie.muc.de>
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions
16 * 1. Redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer.
18 * 2. Redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution.
22 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
23 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
24 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
25 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
26 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
27 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
28 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
29 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
30 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
31 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
32 * POSSIBILITY OF SUCH DAMAGE.
34 * $NetBSD: ip_gre.c,v 1.29 2003/09/05 23:02:43 itojun Exp $
37 #include <sys/cdefs.h>
38 __FBSDID("$FreeBSD$");
41 #include "opt_inet6.h"
43 #include <sys/param.h>
45 #include <sys/systm.h>
46 #include <sys/socket.h>
47 #include <sys/sockio.h>
49 #include <sys/errno.h>
50 #include <sys/kernel.h>
51 #include <sys/sysctl.h>
52 #include <sys/malloc.h>
56 #include <net/if_var.h>
59 #include <netinet/in.h>
60 #include <netinet/in_var.h>
61 #include <netinet/ip.h>
62 #include <netinet/ip_encap.h>
63 #include <netinet/ip_var.h>
66 #include <netinet/ip6.h>
69 #include <net/if_gre.h>
72 VNET_DEFINE(int, ip_gre_ttl) = GRE_TTL;
73 #define V_ip_gre_ttl VNET(ip_gre_ttl)
74 SYSCTL_INT(_net_inet_ip, OID_AUTO, grettl, CTLFLAG_VNET | CTLFLAG_RW,
75 &VNET_NAME(ip_gre_ttl), 0, "Default TTL value for encapsulated packets");
77 VNET_DEFINE_STATIC(struct gre_list *, ipv4_hashtbl) = NULL;
78 #define V_ipv4_hashtbl VNET(ipv4_hashtbl)
79 #define GRE_HASH(src, dst) (V_ipv4_hashtbl[\
80 in_gre_hashval((src), (dst)) & (GRE_HASH_SIZE - 1)])
81 #define GRE_HASH_SC(sc) GRE_HASH((sc)->gre_oip.ip_src.s_addr,\
82 (sc)->gre_oip.ip_dst.s_addr)
85 in_gre_hashval(in_addr_t src, in_addr_t dst)
89 ret = fnv_32_buf(&src, sizeof(src), FNV1_32_INIT);
90 return (fnv_32_buf(&dst, sizeof(dst), ret));
94 in_gre_checkdup(const struct gre_softc *sc, in_addr_t src, in_addr_t dst)
96 struct gre_softc *tmp;
98 if (sc->gre_family == AF_INET &&
99 sc->gre_oip.ip_src.s_addr == src &&
100 sc->gre_oip.ip_dst.s_addr == dst)
103 CK_LIST_FOREACH(tmp, &GRE_HASH(src, dst), chain) {
106 if (tmp->gre_oip.ip_src.s_addr == src &&
107 tmp->gre_oip.ip_dst.s_addr == dst)
108 return (EADDRNOTAVAIL);
114 in_gre_lookup(const struct mbuf *m, int off, int proto, void **arg)
117 struct gre_softc *sc;
119 if (V_ipv4_hashtbl == NULL)
122 MPASS(in_epoch(net_epoch_preempt));
123 ip = mtod(m, const struct ip *);
124 CK_LIST_FOREACH(sc, &GRE_HASH(ip->ip_dst.s_addr,
125 ip->ip_src.s_addr), chain) {
127 * This is an inbound packet, its ip_dst is source address
130 if (sc->gre_oip.ip_src.s_addr == ip->ip_dst.s_addr &&
131 sc->gre_oip.ip_dst.s_addr == ip->ip_src.s_addr) {
132 if ((GRE2IFP(sc)->if_flags & IFF_UP) == 0)
135 return (ENCAP_DRV_LOOKUP);
142 in_gre_attach(struct gre_softc *sc)
145 sc->gre_hlen = sizeof(struct greip);
146 sc->gre_oip.ip_v = IPVERSION;
147 sc->gre_oip.ip_hl = sizeof(struct ip) >> 2;
148 sc->gre_oip.ip_p = IPPROTO_GRE;
149 gre_updatehdr(sc, &sc->gre_gihdr->gi_gre);
150 CK_LIST_INSERT_HEAD(&GRE_HASH_SC(sc), sc, chain);
154 in_gre_setopts(struct gre_softc *sc, u_long cmd, uint32_t value)
157 MPASS(cmd == GRESKEY || cmd == GRESOPTS);
159 /* NOTE: we are protected with gre_ioctl_sx lock */
160 MPASS(sc->gre_family == AF_INET);
161 CK_LIST_REMOVE(sc, chain);
166 sc->gre_options = value;
171 in_gre_ioctl(struct gre_softc *sc, u_long cmd, caddr_t data)
173 struct ifreq *ifr = (struct ifreq *)data;
174 struct sockaddr_in *dst, *src;
178 /* NOTE: we are protected with gre_ioctl_sx lock */
182 src = &((struct in_aliasreq *)data)->ifra_addr;
183 dst = &((struct in_aliasreq *)data)->ifra_dstaddr;
186 if (src->sin_family != dst->sin_family ||
187 src->sin_family != AF_INET ||
188 src->sin_len != dst->sin_len ||
189 src->sin_len != sizeof(*src))
191 if (src->sin_addr.s_addr == INADDR_ANY ||
192 dst->sin_addr.s_addr == INADDR_ANY) {
193 error = EADDRNOTAVAIL;
196 if (V_ipv4_hashtbl == NULL)
197 V_ipv4_hashtbl = gre_hashinit();
198 error = in_gre_checkdup(sc, src->sin_addr.s_addr,
199 dst->sin_addr.s_addr);
200 if (error == EADDRNOTAVAIL)
202 if (error == EEXIST) {
203 /* Addresses are the same. Just return. */
207 ip = malloc(sizeof(struct greip) + 3 * sizeof(uint32_t),
208 M_GRE, M_WAITOK | M_ZERO);
209 ip->ip_src.s_addr = src->sin_addr.s_addr;
210 ip->ip_dst.s_addr = dst->sin_addr.s_addr;
211 if (sc->gre_family != 0) {
212 /* Detach existing tunnel first */
213 CK_LIST_REMOVE(sc, chain);
215 free(sc->gre_hdr, M_GRE);
216 /* XXX: should we notify about link state change? */
218 sc->gre_family = AF_INET;
221 sc->gre_iseq = UINT32_MAX;
224 case SIOCGIFPSRCADDR:
225 case SIOCGIFPDSTADDR:
226 if (sc->gre_family != AF_INET) {
227 error = EADDRNOTAVAIL;
230 src = (struct sockaddr_in *)&ifr->ifr_addr;
231 memset(src, 0, sizeof(*src));
232 src->sin_family = AF_INET;
233 src->sin_len = sizeof(*src);
234 src->sin_addr = (cmd == SIOCGIFPSRCADDR) ?
235 sc->gre_oip.ip_src: sc->gre_oip.ip_dst;
236 error = prison_if(curthread->td_ucred, (struct sockaddr *)src);
238 memset(src, 0, sizeof(*src));
245 in_gre_output(struct mbuf *m, int af, int hlen)
249 gi = mtod(m, struct greip *);
253 * gre_transmit() has used M_PREPEND() that doesn't guarantee
254 * m_data is contiguous more than hlen bytes. Use m_copydata()
255 * here to avoid m_pullup().
257 m_copydata(m, hlen + offsetof(struct ip, ip_tos),
258 sizeof(u_char), &gi->gi_ip.ip_tos);
259 m_copydata(m, hlen + offsetof(struct ip, ip_id),
260 sizeof(u_short), (caddr_t)&gi->gi_ip.ip_id);
264 gi->gi_ip.ip_tos = 0; /* XXX */
265 ip_fillid(&gi->gi_ip);
269 gi->gi_ip.ip_ttl = V_ip_gre_ttl;
270 gi->gi_ip.ip_len = htons(m->m_pkthdr.len);
271 return (ip_output(m, NULL, NULL, IP_FORWARDING, NULL, NULL));
274 static const struct encaptab *ecookie = NULL;
275 static const struct encap_config ipv4_encap_cfg = {
276 .proto = IPPROTO_GRE,
277 .min_length = sizeof(struct greip) + sizeof(struct ip),
278 .exact_match = ENCAP_DRV_LOOKUP,
279 .lookup = in_gre_lookup,
287 if (!IS_DEFAULT_VNET(curvnet))
289 ecookie = ip_encap_attach(&ipv4_encap_cfg, NULL, M_WAITOK);
296 if (IS_DEFAULT_VNET(curvnet))
297 ip_encap_detach(ecookie);
298 if (V_ipv4_hashtbl != NULL)
299 gre_hashdestroy(V_ipv4_hashtbl);