in_gif.c revision 1.41
1 /* $NetBSD: in_gif.c,v 1.41 2005/02/26 22:45:12 perry Exp $ */ 2 /* $KAME: in_gif.c,v 1.66 2001/07/29 04:46:09 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 <sys/cdefs.h> 34 __KERNEL_RCSID(0, "$NetBSD: in_gif.c,v 1.41 2005/02/26 22:45:12 perry Exp $"); 35 36 #include "opt_inet.h" 37 #include "opt_iso.h" 38 39 #include <sys/param.h> 40 #include <sys/systm.h> 41 #include <sys/socket.h> 42 #include <sys/sockio.h> 43 #include <sys/mbuf.h> 44 #include <sys/errno.h> 45 #include <sys/ioctl.h> 46 #include <sys/syslog.h> 47 #include <sys/protosw.h> 48 49 #include <net/if.h> 50 #include <net/route.h> 51 52 #include <netinet/in.h> 53 #include <netinet/in_systm.h> 54 #include <netinet/ip.h> 55 #include <netinet/ip_var.h> 56 #include <netinet/in_gif.h> 57 #include <netinet/in_var.h> 58 #include <netinet/ip_encap.h> 59 #include <netinet/ip_ecn.h> 60 61 #ifdef INET6 62 #include <netinet/ip6.h> 63 #endif 64 65 #include <net/if_gif.h> 66 67 #include "gif.h" 68 #include "bridge.h" 69 #include <net/if_ether.h> 70 71 #include <machine/stdarg.h> 72 73 #include <net/net_osdep.h> 74 75 static int gif_validate4(const struct ip *, struct gif_softc *, 76 struct ifnet *); 77 78 #if NGIF > 0 79 int ip_gif_ttl = GIF_TTL; 80 #else 81 int ip_gif_ttl = 0; 82 #endif 83 84 const struct protosw in_gif_protosw = 85 { SOCK_RAW, &inetdomain, 0/* IPPROTO_IPV[46] */, PR_ATOMIC|PR_ADDR, 86 in_gif_input, rip_output, 0, rip_ctloutput, 87 rip_usrreq, 88 0, 0, 0, 0, 89 }; 90 91 int 92 in_gif_output(struct ifnet *ifp, int family, struct mbuf *m) 93 { 94 struct gif_softc *sc = (struct gif_softc*)ifp; 95 struct sockaddr_in *dst = (struct sockaddr_in *)&sc->gif_ro.ro_dst; 96 struct sockaddr_in *sin_src = (struct sockaddr_in *)sc->gif_psrc; 97 struct sockaddr_in *sin_dst = (struct sockaddr_in *)sc->gif_pdst; 98 struct ip iphdr; /* capsule IP header, host byte ordered */ 99 #if NBRIDGE > 0 100 struct etherip_header eiphdr; 101 #endif 102 int proto, error; 103 u_int8_t tos; 104 105 if (sin_src == NULL || sin_dst == NULL || 106 sin_src->sin_family != AF_INET || 107 sin_dst->sin_family != AF_INET) { 108 m_freem(m); 109 return EAFNOSUPPORT; 110 } 111 112 switch (family) { 113 #ifdef INET 114 case AF_INET: 115 { 116 struct ip *ip; 117 118 proto = IPPROTO_IPV4; 119 if (m->m_len < sizeof(*ip)) { 120 m = m_pullup(m, sizeof(*ip)); 121 if (!m) 122 return ENOBUFS; 123 } 124 ip = mtod(m, struct ip *); 125 tos = ip->ip_tos; 126 break; 127 } 128 #endif /* INET */ 129 #ifdef INET6 130 case AF_INET6: 131 { 132 struct ip6_hdr *ip6; 133 proto = IPPROTO_IPV6; 134 if (m->m_len < sizeof(*ip6)) { 135 m = m_pullup(m, sizeof(*ip6)); 136 if (!m) 137 return ENOBUFS; 138 } 139 ip6 = mtod(m, struct ip6_hdr *); 140 tos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 141 break; 142 } 143 #endif /* INET6 */ 144 #ifdef ISO 145 case AF_ISO: 146 proto = IPPROTO_EON; 147 tos = 0; 148 break; 149 #endif 150 #if NBRIDGE > 0 151 case AF_LINK: 152 proto = IPPROTO_ETHERIP; 153 eiphdr.eip_ver = ETHERIP_VERSION & ETHERIP_VER_VERS_MASK; 154 eiphdr.eip_pad = 0; 155 /* prepend Ethernet-in-IP header */ 156 M_PREPEND(m, sizeof(struct etherip_header), M_DONTWAIT); 157 if (m && m->m_len < sizeof(struct etherip_header)) 158 m = m_pullup(m, sizeof(struct etherip_header)); 159 if (m == NULL) 160 return ENOBUFS; 161 bcopy(&eiphdr, mtod(m, struct etherip_header *), sizeof(struct etherip_header)); 162 break; 163 #endif 164 default: 165 #ifdef DEBUG 166 printf("in_gif_output: warning: unknown family %d passed\n", 167 family); 168 #endif 169 m_freem(m); 170 return EAFNOSUPPORT; 171 } 172 173 bzero(&iphdr, sizeof(iphdr)); 174 iphdr.ip_src = sin_src->sin_addr; 175 /* bidirectional configured tunnel mode */ 176 if (sin_dst->sin_addr.s_addr != INADDR_ANY) 177 iphdr.ip_dst = sin_dst->sin_addr; 178 else { 179 m_freem(m); 180 return ENETUNREACH; 181 } 182 iphdr.ip_p = proto; 183 /* version will be set in ip_output() */ 184 iphdr.ip_ttl = ip_gif_ttl; 185 iphdr.ip_len = htons(m->m_pkthdr.len + sizeof(struct ip)); 186 if (ifp->if_flags & IFF_LINK1) 187 ip_ecn_ingress(ECN_ALLOWED, &iphdr.ip_tos, &tos); 188 else 189 ip_ecn_ingress(ECN_NOCARE, &iphdr.ip_tos, &tos); 190 191 /* prepend new IP header */ 192 M_PREPEND(m, sizeof(struct ip), M_DONTWAIT); 193 if (m && m->m_len < sizeof(struct ip)) 194 m = m_pullup(m, sizeof(struct ip)); 195 if (m == NULL) 196 return ENOBUFS; 197 bcopy(&iphdr, mtod(m, struct ip *), sizeof(struct ip)); 198 199 if (dst->sin_family != sin_dst->sin_family || 200 dst->sin_addr.s_addr != sin_dst->sin_addr.s_addr) { 201 /* cache route doesn't match */ 202 bzero(dst, sizeof(*dst)); 203 dst->sin_family = sin_dst->sin_family; 204 dst->sin_len = sizeof(struct sockaddr_in); 205 dst->sin_addr = sin_dst->sin_addr; 206 if (sc->gif_ro.ro_rt) { 207 RTFREE(sc->gif_ro.ro_rt); 208 sc->gif_ro.ro_rt = NULL; 209 } 210 } 211 212 if (sc->gif_ro.ro_rt == NULL) { 213 rtalloc(&sc->gif_ro); 214 if (sc->gif_ro.ro_rt == NULL) { 215 m_freem(m); 216 return ENETUNREACH; 217 } 218 219 /* if it constitutes infinite encapsulation, punt. */ 220 if (sc->gif_ro.ro_rt->rt_ifp == ifp) { 221 m_freem(m); 222 return ENETUNREACH; /*XXX*/ 223 } 224 } 225 226 error = ip_output(m, NULL, &sc->gif_ro, 0, NULL, NULL); 227 return (error); 228 } 229 230 void 231 in_gif_input(struct mbuf *m, ...) 232 { 233 int off, proto; 234 struct ifnet *gifp = NULL; 235 struct ip *ip; 236 va_list ap; 237 int af; 238 u_int8_t otos; 239 240 va_start(ap, m); 241 off = va_arg(ap, int); 242 proto = va_arg(ap, int); 243 va_end(ap); 244 245 ip = mtod(m, struct ip *); 246 247 gifp = (struct ifnet *)encap_getarg(m); 248 249 if (gifp == NULL || (gifp->if_flags & IFF_UP) == 0) { 250 m_freem(m); 251 ipstat.ips_nogif++; 252 return; 253 } 254 #ifndef GIF_ENCAPCHECK 255 if (!gif_validate4(ip, (struct gif_softc *)gifp, m->m_pkthdr.rcvif)) { 256 m_freem(m); 257 ipstat.ips_nogif++; 258 return; 259 } 260 #endif 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 else 280 ip_ecn_egress(ECN_NOCARE, &otos, &ip->ip_tos); 281 break; 282 } 283 #endif 284 #ifdef INET6 285 case IPPROTO_IPV6: 286 { 287 struct ip6_hdr *ip6; 288 u_int8_t itos; 289 af = AF_INET6; 290 if (m->m_len < sizeof(*ip6)) { 291 m = m_pullup(m, sizeof(*ip6)); 292 if (!m) 293 return; 294 } 295 ip6 = mtod(m, struct ip6_hdr *); 296 itos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 297 if (gifp->if_flags & IFF_LINK1) 298 ip_ecn_egress(ECN_ALLOWED, &otos, &itos); 299 else 300 ip_ecn_egress(ECN_NOCARE, &otos, &itos); 301 ip6->ip6_flow &= ~htonl(0xff << 20); 302 ip6->ip6_flow |= htonl((u_int32_t)itos << 20); 303 break; 304 } 305 #endif /* INET6 */ 306 #ifdef ISO 307 case IPPROTO_EON: 308 af = AF_ISO; 309 break; 310 #endif 311 #if NBRIDGE > 0 312 case IPPROTO_ETHERIP: 313 af = AF_LINK; 314 break; 315 #endif 316 default: 317 ipstat.ips_nogif++; 318 m_freem(m); 319 return; 320 } 321 gif_input(m, af, gifp); 322 return; 323 } 324 325 /* 326 * validate outer address. 327 */ 328 static int 329 gif_validate4(const struct ip *ip, struct gif_softc *sc, struct ifnet *ifp) 330 { 331 struct sockaddr_in *src, *dst; 332 struct in_ifaddr *ia4; 333 334 src = (struct sockaddr_in *)sc->gif_psrc; 335 dst = (struct sockaddr_in *)sc->gif_pdst; 336 337 /* check for address match */ 338 if (src->sin_addr.s_addr != ip->ip_dst.s_addr || 339 dst->sin_addr.s_addr != ip->ip_src.s_addr) 340 return 0; 341 342 /* martian filters on outer source - NOT done in ip_input! */ 343 if (IN_MULTICAST(ip->ip_src.s_addr)) 344 return 0; 345 switch ((ntohl(ip->ip_src.s_addr) & 0xff000000) >> 24) { 346 case 0: case 127: case 255: 347 return 0; 348 } 349 /* reject packets with broadcast on source */ 350 TAILQ_FOREACH(ia4, &in_ifaddrhead, ia_list) { 351 if ((ia4->ia_ifa.ifa_ifp->if_flags & IFF_BROADCAST) == 0) 352 continue; 353 if (ip->ip_src.s_addr == ia4->ia_broadaddr.sin_addr.s_addr) 354 return 0; 355 } 356 357 /* ingress filters on outer source */ 358 if ((sc->gif_if.if_flags & IFF_LINK2) == 0 && ifp) { 359 struct sockaddr_in sin; 360 struct rtentry *rt; 361 362 bzero(&sin, sizeof(sin)); 363 sin.sin_family = AF_INET; 364 sin.sin_len = sizeof(struct sockaddr_in); 365 sin.sin_addr = ip->ip_src; 366 rt = rtalloc1((struct sockaddr *)&sin, 0); 367 if (!rt || rt->rt_ifp != ifp) { 368 #if 0 369 log(LOG_WARNING, "%s: packet from 0x%x dropped " 370 "due to ingress filter\n", if_name(&sc->gif_if), 371 (u_int32_t)ntohl(sin.sin_addr.s_addr)); 372 #endif 373 if (rt) 374 rtfree(rt); 375 return 0; 376 } 377 rtfree(rt); 378 } 379 380 return 32 * 2; 381 } 382 383 #ifdef GIF_ENCAPCHECK 384 /* 385 * we know that we are in IFF_UP, outer address available, and outer family 386 * matched the physical addr family. see gif_encapcheck(). 387 */ 388 int 389 gif_encapcheck4(const struct mbuf *m, int off, int proto, void *arg) 390 { 391 struct ip ip; 392 struct gif_softc *sc; 393 struct ifnet *ifp; 394 395 /* sanity check done in caller */ 396 sc = (struct gif_softc *)arg; 397 398 /* LINTED const cast */ 399 m_copydata((struct mbuf *)m, 0, sizeof(ip), (caddr_t)&ip); 400 ifp = ((m->m_flags & M_PKTHDR) != 0) ? m->m_pkthdr.rcvif : NULL; 401 402 return gif_validate4(&ip, sc, ifp); 403 } 404 #endif 405 406 int 407 in_gif_attach(struct gif_softc *sc) 408 { 409 #ifndef GIF_ENCAPCHECK 410 struct sockaddr_in mask4; 411 412 bzero(&mask4, sizeof(mask4)); 413 mask4.sin_len = sizeof(struct sockaddr_in); 414 mask4.sin_addr.s_addr = ~0; 415 416 if (!sc->gif_psrc || !sc->gif_pdst) 417 return EINVAL; 418 sc->encap_cookie4 = encap_attach(AF_INET, -1, sc->gif_psrc, 419 (struct sockaddr *)&mask4, sc->gif_pdst, (struct sockaddr *)&mask4, 420 (struct protosw *)&in_gif_protosw, sc); 421 #else 422 sc->encap_cookie4 = encap_attach_func(AF_INET, -1, gif_encapcheck, 423 &in_gif_protosw, sc); 424 #endif 425 if (sc->encap_cookie4 == NULL) 426 return EEXIST; 427 return 0; 428 } 429 430 int 431 in_gif_detach(struct gif_softc *sc) 432 { 433 int error; 434 435 error = encap_detach(sc->encap_cookie4); 436 if (error == 0) 437 sc->encap_cookie4 = NULL; 438 return error; 439 } 440
Indexes created Wed Sep 24 05:09:52 GMT 2025