in_gif.c revision 1.18
1 /* $NetBSD: in_gif.c,v 1.18 2001/02/20 08:49:15 itojun Exp $ */ 2 /* $KAME: in_gif.c,v 1.51 2001/02/20 08:31:07 itojun Exp $ */ 3 4 /* 5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the project nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 #include "opt_inet.h" 34 #include "opt_iso.h" 35 36 #include <sys/param.h> 37 #include <sys/systm.h> 38 #include <sys/socket.h> 39 #include <sys/sockio.h> 40 #include <sys/mbuf.h> 41 #include <sys/errno.h> 42 #include <sys/ioctl.h> 43 #include <sys/syslog.h> 44 45 #include <net/if.h> 46 #include <net/route.h> 47 48 #include <netinet/in.h> 49 #include <netinet/in_systm.h> 50 #include <netinet/ip.h> 51 #include <netinet/ip_var.h> 52 #include <netinet/in_gif.h> 53 #include <netinet/in_var.h> 54 #include <netinet/ip_encap.h> 55 #include <netinet/ip_ecn.h> 56 #ifdef __OpenBSD__ 57 #include <netinet/ip_ipsp.h> 58 #endif 59 60 #ifdef INET6 61 #include <netinet/ip6.h> 62 #endif 63 64 #ifdef MROUTING 65 #include <netinet/ip_mroute.h> 66 #endif /* MROUTING */ 67 68 #include <net/if_gif.h> 69 70 #include "gif.h" 71 72 #include <machine/stdarg.h> 73 74 #include <net/net_osdep.h> 75 76 #if NGIF > 0 77 int ip_gif_ttl = GIF_TTL; 78 #else 79 int ip_gif_ttl = 0; 80 #endif 81 82 int 83 in_gif_output(ifp, family, m, rt) 84 struct ifnet *ifp; 85 int family; 86 struct mbuf *m; 87 struct rtentry *rt; 88 { 89 struct gif_softc *sc = (struct gif_softc*)ifp; 90 struct sockaddr_in *dst = (struct sockaddr_in *)&sc->gif_ro.ro_dst; 91 struct sockaddr_in *sin_src = (struct sockaddr_in *)sc->gif_psrc; 92 struct sockaddr_in *sin_dst = (struct sockaddr_in *)sc->gif_pdst; 93 struct ip iphdr; /* capsule IP header, host byte ordered */ 94 int proto, error; 95 u_int8_t tos; 96 97 if (sin_src == NULL || sin_dst == NULL || 98 sin_src->sin_family != AF_INET || 99 sin_dst->sin_family != AF_INET) { 100 m_freem(m); 101 return EAFNOSUPPORT; 102 } 103 104 switch (family) { 105 #ifdef INET 106 case AF_INET: 107 { 108 struct ip *ip; 109 110 proto = IPPROTO_IPV4; 111 if (m->m_len < sizeof(*ip)) { 112 m = m_pullup(m, sizeof(*ip)); 113 if (!m) 114 return ENOBUFS; 115 } 116 ip = mtod(m, struct ip *); 117 tos = ip->ip_tos; 118 break; 119 } 120 #endif /*INET*/ 121 #ifdef INET6 122 case AF_INET6: 123 { 124 struct ip6_hdr *ip6; 125 proto = IPPROTO_IPV6; 126 if (m->m_len < sizeof(*ip6)) { 127 m = m_pullup(m, sizeof(*ip6)); 128 if (!m) 129 return ENOBUFS; 130 } 131 ip6 = mtod(m, struct ip6_hdr *); 132 tos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 133 break; 134 } 135 #endif /*INET6*/ 136 default: 137 #ifdef DEBUG 138 printf("in_gif_output: warning: unknown family %d passed\n", 139 family); 140 #endif 141 m_freem(m); 142 return EAFNOSUPPORT; 143 } 144 145 bzero(&iphdr, sizeof(iphdr)); 146 iphdr.ip_src = sin_src->sin_addr; 147 if (ifp->if_flags & IFF_LINK0) { 148 /* multi-destination mode */ 149 if (sin_dst->sin_addr.s_addr != INADDR_ANY) 150 iphdr.ip_dst = sin_dst->sin_addr; 151 else if (rt) { 152 if (family != AF_INET) { 153 m_freem(m); 154 return EINVAL; /*XXX*/ 155 } 156 iphdr.ip_dst = ((struct sockaddr_in *) 157 (rt->rt_gateway))->sin_addr; 158 } else { 159 m_freem(m); 160 return ENETUNREACH; 161 } 162 } else { 163 /* bidirectional configured tunnel mode */ 164 if (sin_dst->sin_addr.s_addr != INADDR_ANY) 165 iphdr.ip_dst = sin_dst->sin_addr; 166 else { 167 m_freem(m); 168 return ENETUNREACH; 169 } 170 } 171 iphdr.ip_p = proto; 172 /* version will be set in ip_output() */ 173 iphdr.ip_ttl = ip_gif_ttl; 174 iphdr.ip_len = m->m_pkthdr.len + sizeof(struct ip); 175 if (ifp->if_flags & IFF_LINK1) 176 ip_ecn_ingress(ECN_ALLOWED, &iphdr.ip_tos, &tos); 177 178 /* prepend new IP header */ 179 M_PREPEND(m, sizeof(struct ip), M_DONTWAIT); 180 if (m && m->m_len < sizeof(struct ip)) 181 m = m_pullup(m, sizeof(struct ip)); 182 if (m == NULL) { 183 printf("ENOBUFS in in_gif_output %d\n", __LINE__); 184 return ENOBUFS; 185 } 186 bcopy(&iphdr, mtod(m, struct ip *), sizeof(struct ip)); 187 188 if (dst->sin_family != sin_dst->sin_family || 189 dst->sin_addr.s_addr != sin_dst->sin_addr.s_addr) { 190 /* cache route doesn't match */ 191 dst->sin_family = sin_dst->sin_family; 192 dst->sin_len = sizeof(struct sockaddr_in); 193 dst->sin_addr = sin_dst->sin_addr; 194 if (sc->gif_ro.ro_rt) { 195 RTFREE(sc->gif_ro.ro_rt); 196 sc->gif_ro.ro_rt = NULL; 197 } 198 #if 0 199 sc->gif_if.if_mtu = GIF_MTU; 200 #endif 201 } 202 203 if (sc->gif_ro.ro_rt == NULL) { 204 rtalloc(&sc->gif_ro); 205 if (sc->gif_ro.ro_rt == NULL) { 206 m_freem(m); 207 return ENETUNREACH; 208 } 209 210 /* if it constitutes infinite encapsulation, punt. */ 211 if (sc->gif_ro.ro_rt->rt_ifp == ifp) { 212 m_freem(m); 213 return ENETUNREACH; /*XXX*/ 214 } 215 #if 0 216 ifp->if_mtu = sc->gif_ro.ro_rt->rt_ifp->if_mtu 217 - sizeof(struct ip); 218 #endif 219 } 220 221 error = ip_output(m, NULL, &sc->gif_ro, 0, NULL); 222 return(error); 223 } 224 225 void 226 #if __STDC__ 227 in_gif_input(struct mbuf *m, ...) 228 #else 229 in_gif_input(m, va_alist) 230 struct mbuf *m; 231 va_dcl 232 #endif 233 { 234 int off, proto; 235 struct ifnet *gifp = NULL; 236 struct ip *ip; 237 va_list ap; 238 int af; 239 u_int8_t otos; 240 241 va_start(ap, m); 242 off = va_arg(ap, int); 243 proto = va_arg(ap, int); 244 va_end(ap); 245 246 ip = mtod(m, struct ip *); 247 248 gifp = (struct ifnet *)encap_getarg(m); 249 250 if (gifp == NULL || (gifp->if_flags & IFF_UP) == 0) { 251 m_freem(m); 252 ipstat.ips_nogif++; 253 return; 254 } 255 256 otos = ip->ip_tos; 257 m_adj(m, off); 258 259 switch (proto) { 260 #ifdef INET 261 case IPPROTO_IPV4: 262 { 263 struct ip *ip; 264 af = AF_INET; 265 if (m->m_len < sizeof(*ip)) { 266 m = m_pullup(m, sizeof(*ip)); 267 if (!m) 268 return; 269 } 270 ip = mtod(m, struct ip *); 271 if (gifp->if_flags & IFF_LINK1) 272 ip_ecn_egress(ECN_ALLOWED, &otos, &ip->ip_tos); 273 break; 274 } 275 #endif 276 #ifdef INET6 277 case IPPROTO_IPV6: 278 { 279 struct ip6_hdr *ip6; 280 u_int8_t itos; 281 af = AF_INET6; 282 if (m->m_len < sizeof(*ip6)) { 283 m = m_pullup(m, sizeof(*ip6)); 284 if (!m) 285 return; 286 } 287 ip6 = mtod(m, struct ip6_hdr *); 288 itos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 289 if (gifp->if_flags & IFF_LINK1) 290 ip_ecn_egress(ECN_ALLOWED, &otos, &itos); 291 ip6->ip6_flow &= ~htonl(0xff << 20); 292 ip6->ip6_flow |= htonl((u_int32_t)itos << 20); 293 break; 294 } 295 #endif /* INET6 */ 296 #ifdef ISO 297 case IPPROTO_EON: 298 af = AF_ISO; 299 break; 300 #endif 301 default: 302 ipstat.ips_nogif++; 303 m_freem(m); 304 return; 305 } 306 gif_input(m, af, gifp); 307 return; 308 } 309 310 /* 311 * we know that we are in IFF_UP, outer address available, and outer family 312 * matched the physical addr family. see gif_encapcheck(). 313 */ 314 int 315 gif_encapcheck4(m, off, proto, arg) 316 const struct mbuf *m; 317 int off; 318 int proto; 319 void *arg; 320 { 321 struct ip ip; 322 struct gif_softc *sc; 323 struct sockaddr_in *src, *dst; 324 int addrmatch; 325 struct in_ifaddr *ia4; 326 327 /* sanity check done in caller */ 328 sc = (struct gif_softc *)arg; 329 src = (struct sockaddr_in *)sc->gif_psrc; 330 dst = (struct sockaddr_in *)sc->gif_pdst; 331 332 /* LINTED const cast */ 333 m_copydata((struct mbuf *)m, 0, sizeof(ip), (caddr_t)&ip); 334 335 /* check for address match */ 336 addrmatch = 0; 337 if (src->sin_addr.s_addr == ip.ip_dst.s_addr) 338 addrmatch |= 1; 339 if (dst->sin_addr.s_addr == ip.ip_src.s_addr) 340 addrmatch |= 2; 341 else if ((sc->gif_if.if_flags & IFF_LINK0) != 0 && 342 dst->sin_addr.s_addr == INADDR_ANY) { 343 addrmatch |= 2; /* we accept any source */ 344 } 345 if (addrmatch != 3) 346 return 0; 347 348 /* martian filters on outer source - NOT done in ip_input! */ 349 if (IN_MULTICAST(ip.ip_src.s_addr)) 350 return 0; 351 switch ((ntohl(ip.ip_src.s_addr) & 0xff000000) >> 24) { 352 case 0: case 127: case 255: 353 return 0; 354 } 355 /* reject packets with broadcast on source */ 356 for (ia4 = in_ifaddr.tqh_first; ia4; ia4 = ia4->ia_list.tqe_next) 357 { 358 if ((ia4->ia_ifa.ifa_ifp->if_flags & IFF_BROADCAST) == 0) 359 continue; 360 if (ip.ip_src.s_addr == ia4->ia_broadaddr.sin_addr.s_addr) 361 return 0; 362 } 363 364 /* ingress filters on outer source */ 365 if ((sc->gif_if.if_flags & IFF_LINK2) == 0 && 366 (m->m_flags & M_PKTHDR) != 0 && m->m_pkthdr.rcvif) { 367 struct sockaddr_in sin; 368 struct rtentry *rt; 369 370 bzero(&sin, sizeof(sin)); 371 sin.sin_family = AF_INET; 372 sin.sin_len = sizeof(struct sockaddr_in); 373 sin.sin_addr = ip.ip_src; 374 rt = rtalloc1((struct sockaddr *)&sin, 0); 375 if (!rt || rt->rt_ifp != m->m_pkthdr.rcvif) { 376 #if 0 377 log(LOG_WARNING, "%s: packet from 0x%x dropped " 378 "due to ingress filter\n", if_name(&sc->gif_if), 379 (u_int32_t)ntohl(sin.sin_addr.s_addr)); 380 #endif 381 if (rt) 382 rtfree(rt); 383 return 0; 384 } 385 rtfree(rt); 386 } 387 388 /* prioritize: IFF_LINK0 mode is less preferred */ 389 return (sc->gif_if.if_flags & IFF_LINK0) ? 32 : 32 * 2; 390 } 391
Indexes created Fri Sep 26 20:09:58 GMT 2025