in_gif.c revision 1.19
1 /* $NetBSD: in_gif.c,v 1.19 2001/02/20 10:41:47 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 #ifdef ISO 137 case AF_ISO: 138 proto = IPPROTO_EON; 139 tos = 0; 140 break; 141 #endif 142 default: 143 #ifdef DEBUG 144 printf("in_gif_output: warning: unknown family %d passed\n", 145 family); 146 #endif 147 m_freem(m); 148 return EAFNOSUPPORT; 149 } 150 151 bzero(&iphdr, sizeof(iphdr)); 152 iphdr.ip_src = sin_src->sin_addr; 153 if (ifp->if_flags & IFF_LINK0) { 154 /* multi-destination mode */ 155 if (sin_dst->sin_addr.s_addr != INADDR_ANY) 156 iphdr.ip_dst = sin_dst->sin_addr; 157 else if (rt) { 158 if (family != AF_INET) { 159 m_freem(m); 160 return EINVAL; /*XXX*/ 161 } 162 iphdr.ip_dst = ((struct sockaddr_in *) 163 (rt->rt_gateway))->sin_addr; 164 } else { 165 m_freem(m); 166 return ENETUNREACH; 167 } 168 } else { 169 /* bidirectional configured tunnel mode */ 170 if (sin_dst->sin_addr.s_addr != INADDR_ANY) 171 iphdr.ip_dst = sin_dst->sin_addr; 172 else { 173 m_freem(m); 174 return ENETUNREACH; 175 } 176 } 177 iphdr.ip_p = proto; 178 /* version will be set in ip_output() */ 179 iphdr.ip_ttl = ip_gif_ttl; 180 iphdr.ip_len = m->m_pkthdr.len + sizeof(struct ip); 181 if (ifp->if_flags & IFF_LINK1) 182 ip_ecn_ingress(ECN_ALLOWED, &iphdr.ip_tos, &tos); 183 184 /* prepend new IP header */ 185 M_PREPEND(m, sizeof(struct ip), M_DONTWAIT); 186 if (m && m->m_len < sizeof(struct ip)) 187 m = m_pullup(m, sizeof(struct ip)); 188 if (m == NULL) { 189 printf("ENOBUFS in in_gif_output %d\n", __LINE__); 190 return ENOBUFS; 191 } 192 bcopy(&iphdr, mtod(m, struct ip *), sizeof(struct ip)); 193 194 if (dst->sin_family != sin_dst->sin_family || 195 dst->sin_addr.s_addr != sin_dst->sin_addr.s_addr) { 196 /* cache route doesn't match */ 197 dst->sin_family = sin_dst->sin_family; 198 dst->sin_len = sizeof(struct sockaddr_in); 199 dst->sin_addr = sin_dst->sin_addr; 200 if (sc->gif_ro.ro_rt) { 201 RTFREE(sc->gif_ro.ro_rt); 202 sc->gif_ro.ro_rt = NULL; 203 } 204 #if 0 205 sc->gif_if.if_mtu = GIF_MTU; 206 #endif 207 } 208 209 if (sc->gif_ro.ro_rt == NULL) { 210 rtalloc(&sc->gif_ro); 211 if (sc->gif_ro.ro_rt == NULL) { 212 m_freem(m); 213 return ENETUNREACH; 214 } 215 216 /* if it constitutes infinite encapsulation, punt. */ 217 if (sc->gif_ro.ro_rt->rt_ifp == ifp) { 218 m_freem(m); 219 return ENETUNREACH; /*XXX*/ 220 } 221 #if 0 222 ifp->if_mtu = sc->gif_ro.ro_rt->rt_ifp->if_mtu 223 - sizeof(struct ip); 224 #endif 225 } 226 227 error = ip_output(m, NULL, &sc->gif_ro, 0, NULL); 228 return(error); 229 } 230 231 void 232 #if __STDC__ 233 in_gif_input(struct mbuf *m, ...) 234 #else 235 in_gif_input(m, va_alist) 236 struct mbuf *m; 237 va_dcl 238 #endif 239 { 240 int off, proto; 241 struct ifnet *gifp = NULL; 242 struct ip *ip; 243 va_list ap; 244 int af; 245 u_int8_t otos; 246 247 va_start(ap, m); 248 off = va_arg(ap, int); 249 proto = va_arg(ap, int); 250 va_end(ap); 251 252 ip = mtod(m, struct ip *); 253 254 gifp = (struct ifnet *)encap_getarg(m); 255 256 if (gifp == NULL || (gifp->if_flags & IFF_UP) == 0) { 257 m_freem(m); 258 ipstat.ips_nogif++; 259 return; 260 } 261 262 otos = ip->ip_tos; 263 m_adj(m, off); 264 265 switch (proto) { 266 #ifdef INET 267 case IPPROTO_IPV4: 268 { 269 struct ip *ip; 270 af = AF_INET; 271 if (m->m_len < sizeof(*ip)) { 272 m = m_pullup(m, sizeof(*ip)); 273 if (!m) 274 return; 275 } 276 ip = mtod(m, struct ip *); 277 if (gifp->if_flags & IFF_LINK1) 278 ip_ecn_egress(ECN_ALLOWED, &otos, &ip->ip_tos); 279 break; 280 } 281 #endif 282 #ifdef INET6 283 case IPPROTO_IPV6: 284 { 285 struct ip6_hdr *ip6; 286 u_int8_t itos; 287 af = AF_INET6; 288 if (m->m_len < sizeof(*ip6)) { 289 m = m_pullup(m, sizeof(*ip6)); 290 if (!m) 291 return; 292 } 293 ip6 = mtod(m, struct ip6_hdr *); 294 itos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 295 if (gifp->if_flags & IFF_LINK1) 296 ip_ecn_egress(ECN_ALLOWED, &otos, &itos); 297 ip6->ip6_flow &= ~htonl(0xff << 20); 298 ip6->ip6_flow |= htonl((u_int32_t)itos << 20); 299 break; 300 } 301 #endif /* INET6 */ 302 #ifdef ISO 303 case IPPROTO_EON: 304 af = AF_ISO; 305 break; 306 #endif 307 default: 308 ipstat.ips_nogif++; 309 m_freem(m); 310 return; 311 } 312 gif_input(m, af, gifp); 313 return; 314 } 315 316 /* 317 * we know that we are in IFF_UP, outer address available, and outer family 318 * matched the physical addr family. see gif_encapcheck(). 319 */ 320 int 321 gif_encapcheck4(m, off, proto, arg) 322 const struct mbuf *m; 323 int off; 324 int proto; 325 void *arg; 326 { 327 struct ip ip; 328 struct gif_softc *sc; 329 struct sockaddr_in *src, *dst; 330 int addrmatch; 331 struct in_ifaddr *ia4; 332 333 /* sanity check done in caller */ 334 sc = (struct gif_softc *)arg; 335 src = (struct sockaddr_in *)sc->gif_psrc; 336 dst = (struct sockaddr_in *)sc->gif_pdst; 337 338 /* LINTED const cast */ 339 m_copydata((struct mbuf *)m, 0, sizeof(ip), (caddr_t)&ip); 340 341 /* check for address match */ 342 addrmatch = 0; 343 if (src->sin_addr.s_addr == ip.ip_dst.s_addr) 344 addrmatch |= 1; 345 if (dst->sin_addr.s_addr == ip.ip_src.s_addr) 346 addrmatch |= 2; 347 else if ((sc->gif_if.if_flags & IFF_LINK0) != 0 && 348 dst->sin_addr.s_addr == INADDR_ANY) { 349 addrmatch |= 2; /* we accept any source */ 350 } 351 if (addrmatch != 3) 352 return 0; 353 354 /* martian filters on outer source - NOT done in ip_input! */ 355 if (IN_MULTICAST(ip.ip_src.s_addr)) 356 return 0; 357 switch ((ntohl(ip.ip_src.s_addr) & 0xff000000) >> 24) { 358 case 0: case 127: case 255: 359 return 0; 360 } 361 /* reject packets with broadcast on source */ 362 for (ia4 = in_ifaddr.tqh_first; ia4; ia4 = ia4->ia_list.tqe_next) 363 { 364 if ((ia4->ia_ifa.ifa_ifp->if_flags & IFF_BROADCAST) == 0) 365 continue; 366 if (ip.ip_src.s_addr == ia4->ia_broadaddr.sin_addr.s_addr) 367 return 0; 368 } 369 370 /* ingress filters on outer source */ 371 if ((sc->gif_if.if_flags & IFF_LINK2) == 0 && 372 (m->m_flags & M_PKTHDR) != 0 && m->m_pkthdr.rcvif) { 373 struct sockaddr_in sin; 374 struct rtentry *rt; 375 376 bzero(&sin, sizeof(sin)); 377 sin.sin_family = AF_INET; 378 sin.sin_len = sizeof(struct sockaddr_in); 379 sin.sin_addr = ip.ip_src; 380 rt = rtalloc1((struct sockaddr *)&sin, 0); 381 if (!rt || rt->rt_ifp != m->m_pkthdr.rcvif) { 382 #if 0 383 log(LOG_WARNING, "%s: packet from 0x%x dropped " 384 "due to ingress filter\n", if_name(&sc->gif_if), 385 (u_int32_t)ntohl(sin.sin_addr.s_addr)); 386 #endif 387 if (rt) 388 rtfree(rt); 389 return 0; 390 } 391 rtfree(rt); 392 } 393 394 /* prioritize: IFF_LINK0 mode is less preferred */ 395 return (sc->gif_if.if_flags & IFF_LINK0) ? 32 : 32 * 2; 396 } 397
Indexes created Fri Sep 26 08:10:20 GMT 2025