1 /* 2 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 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 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the project nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * $FreeBSD$ 30 */ 31 32 /* 33 * in_gif.c 34 */ 35 36 #include "opt_mrouting.h" 37 #include "opt_inet6.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/kernel.h> 46 #include <sys/sysctl.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 #ifdef INET6 56 #include <netinet/ip6.h> 57 #endif 58 #include <netinet/ip_var.h> 59 #include <netinet/in_gif.h> 60 #include <netinet/ip_ecn.h> 61 #ifdef INET6 62 #include <netinet6/ip6_ecn.h> 63 #endif 64 65 #ifdef MROUTING 66 #include <netinet/ip_mroute.h> 67 #endif /* MROUTING */ 68 69 #include <net/if_gif.h> 70 71 #include "gif.h" 72 73 #include <machine/stdarg.h> 74 75 #include <net/net_osdep.h> 76 77 #if NGIF > 0 78 int ip_gif_ttl = GIF_TTL; 79 #else 80 int ip_gif_ttl = 0; 81 #endif 82 83 SYSCTL_DECL(_net_inet_ip); 84 SYSCTL_INT(_net_inet_ip, IPCTL_GIF_TTL, gifttl, CTLFLAG_RW, 85 &ip_gif_ttl, 0, ""); 86 87 int 88 in_gif_output(ifp, family, m, rt) 89 struct ifnet *ifp; 90 int family; 91 struct mbuf *m; 92 struct rtentry *rt; 93 { 94 register 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 int proto, error; 100 u_int8_t tos; 101 102 if (sin_src == NULL || sin_dst == NULL || 103 sin_src->sin_family != AF_INET || 104 sin_dst->sin_family != AF_INET) { 105 m_freem(m); 106 return EAFNOSUPPORT; 107 } 108 109 switch (family) { 110 case AF_INET: 111 { 112 struct ip *ip; 113 114 proto = IPPROTO_IPV4; 115 if (m->m_len < sizeof(*ip)) { 116 m = m_pullup(m, sizeof(*ip)); 117 if (!m) 118 return ENOBUFS; 119 } 120 ip = mtod(m, struct ip *); 121 tos = ip->ip_tos; 122 break; 123 } 124 #ifdef INET6 125 case AF_INET6: 126 { 127 struct ip6_hdr *ip6; 128 proto = IPPROTO_IPV6; 129 if (m->m_len < sizeof(*ip6)) { 130 m = m_pullup(m, sizeof(*ip6)); 131 if (!m) 132 return ENOBUFS; 133 } 134 ip6 = mtod(m, struct ip6_hdr *); 135 tos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 136 break; 137 } 138 #endif /*INET6*/ 139 default: 140 #ifdef DIAGNOSTIC 141 printf("in_gif_output: warning: unknown family %d passed\n", 142 family); 143 #endif 144 m_freem(m); 145 return EAFNOSUPPORT; 146 } 147 148 bzero(&iphdr, sizeof(iphdr)); 149 iphdr.ip_src = sin_src->sin_addr; 150 if (ifp->if_flags & IFF_LINK0) { 151 /* multi-destination mode */ 152 if (sin_dst->sin_addr.s_addr != INADDR_ANY) 153 iphdr.ip_dst = sin_dst->sin_addr; 154 else if (rt) { 155 iphdr.ip_dst = ((struct sockaddr_in *) 156 (rt->rt_gateway))->sin_addr; 157 } else { 158 m_freem(m); 159 return ENETUNREACH; 160 } 161 } else { 162 /* bidirectional configured tunnel mode */ 163 if (sin_dst->sin_addr.s_addr != INADDR_ANY) 164 iphdr.ip_dst = sin_dst->sin_addr; 165 else { 166 m_freem(m); 167 return ENETUNREACH; 168 } 169 } 170 iphdr.ip_p = proto; 171 /* version will be set in ip_output() */ 172 iphdr.ip_ttl = ip_gif_ttl; 173 iphdr.ip_len = m->m_pkthdr.len + sizeof(struct ip); 174 if (ifp->if_flags & IFF_LINK1) 175 ip_ecn_ingress(ECN_ALLOWED, &iphdr.ip_tos, &tos); 176 177 /* prepend new IP header */ 178 M_PREPEND(m, sizeof(struct ip), M_DONTWAIT); 179 if (m && m->m_len < sizeof(struct ip)) 180 m = m_pullup(m, sizeof(struct ip)); 181 if (m == NULL) { 182 printf("ENOBUFS in in_gif_output %d\n", __LINE__); 183 return ENOBUFS; 184 } 185 186 *(mtod(m, struct ip *)) = iphdr; 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 } 199 200 if (sc->gif_ro.ro_rt == NULL) { 201 rtalloc(&sc->gif_ro); 202 if (sc->gif_ro.ro_rt == NULL) { 203 m_freem(m); 204 return ENETUNREACH; 205 } 206 } 207 208 error = ip_output(m, 0, &sc->gif_ro, 0, 0); 209 return(error); 210 } 211 212 void 213 in_gif_input(struct mbuf *m, int off, int proto) 214 { 215 struct gif_softc *sc; 216 struct ifnet *gifp = NULL; 217 struct ip *ip; 218 int i, af; 219 u_int8_t otos; 220 221 ip = mtod(m, struct ip *); 222 223 /* this code will be soon improved. */ 224 #define satosin(sa) ((struct sockaddr_in *)(sa)) 225 for (i = 0, sc = gif; i < ngif; i++, sc++) { 226 if (sc->gif_psrc == NULL 227 || sc->gif_pdst == NULL 228 || sc->gif_psrc->sa_family != AF_INET 229 || sc->gif_pdst->sa_family != AF_INET) { 230 continue; 231 } 232 233 if ((sc->gif_if.if_flags & IFF_UP) == 0) 234 continue; 235 236 if ((sc->gif_if.if_flags & IFF_LINK0) 237 && satosin(sc->gif_psrc)->sin_addr.s_addr == ip->ip_dst.s_addr 238 && satosin(sc->gif_pdst)->sin_addr.s_addr == INADDR_ANY) { 239 gifp = &sc->gif_if; 240 continue; 241 } 242 243 if (satosin(sc->gif_psrc)->sin_addr.s_addr == ip->ip_dst.s_addr 244 && satosin(sc->gif_pdst)->sin_addr.s_addr == ip->ip_src.s_addr) 245 { 246 gifp = &sc->gif_if; 247 break; 248 } 249 } 250 251 if (gifp == NULL) { 252 #ifdef MROUTING 253 /* for backward compatibility */ 254 if (proto == IPPROTO_IPV4) { 255 ipip_input(m, off, proto); 256 return; 257 } 258 #endif /*MROUTING*/ 259 m_freem(m); 260 ipstat.ips_nogif++; 261 return; 262 } 263 264 otos = ip->ip_tos; 265 m_adj(m, off); 266 267 switch (proto) { 268 case IPPROTO_IPV4: 269 { 270 struct ip *ip; 271 af = AF_INET; 272 if (m->m_len < sizeof(*ip)) { 273 m = m_pullup(m, sizeof(*ip)); 274 if (!m) 275 return; 276 } 277 ip = mtod(m, struct ip *); 278 if (gifp->if_flags & IFF_LINK1) 279 ip_ecn_egress(ECN_ALLOWED, &otos, &ip->ip_tos); 280 break; 281 } 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 default: 303 ipstat.ips_nogif++; 304 m_freem(m); 305 return; 306 } 307 gif_input(m, af, gifp); 308 return; 309 } 310