1 /* $NetBSD: if_faith.c,v 1.56 2017/10/23 09:32:00 msaitoh Exp $ */ 2 /* $KAME: if_faith.c,v 1.21 2001/02/20 07:59:26 itojun Exp $ */ 3 4 /* 5 * Copyright (c) 1982, 1986, 1993 6 * The Regents of the University of California. 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 University 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 REGENTS 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 REGENTS 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 * derived from 34 * @(#)if_loop.c 8.1 (Berkeley) 6/10/93 35 * Id: if_loop.c,v 1.22 1996/06/19 16:24:10 wollman Exp 36 */ 37 38 /* 39 * IPv6-to-IPv4 TCP relay capturing interface 40 */ 41 42 #include <sys/cdefs.h> 43 __KERNEL_RCSID(0, "$NetBSD: if_faith.c,v 1.56 2017/10/23 09:32:00 msaitoh Exp $"); 44 45 #ifdef _KERNEL_OPT 46 #include "opt_inet.h" 47 #endif 48 49 #include <sys/param.h> 50 #include <sys/systm.h> 51 #include <sys/kernel.h> 52 #include <sys/mbuf.h> 53 #include <sys/socket.h> 54 #include <sys/errno.h> 55 #include <sys/ioctl.h> 56 #include <sys/time.h> 57 #include <sys/queue.h> 58 #include <sys/device.h> 59 #include <sys/module.h> 60 #include <sys/atomic.h> 61 62 #include <sys/cpu.h> 63 64 #include <net/if.h> 65 #include <net/if_types.h> 66 #include <net/netisr.h> 67 #include <net/route.h> 68 #include <net/bpf.h> 69 #include <net/if_faith.h> 70 71 #ifdef INET 72 #include <netinet/in.h> 73 #include <netinet/in_systm.h> 74 #include <netinet/in_var.h> 75 #include <netinet/ip.h> 76 #endif 77 78 #ifdef INET6 79 #ifndef INET 80 #include <netinet/in.h> 81 #endif 82 #include <netinet6/in6_var.h> 83 #include <netinet/ip6.h> 84 #include <netinet6/ip6_var.h> 85 #endif 86 87 88 #include <net/net_osdep.h> 89 90 #include "ioconf.h" 91 92 static int faithioctl(struct ifnet *, u_long, void *); 93 static int faithoutput(struct ifnet *, struct mbuf *, 94 const struct sockaddr *, const struct rtentry *); 95 static void faithrtrequest(int, struct rtentry *, 96 const struct rt_addrinfo *); 97 98 static int faith_clone_create(struct if_clone *, int); 99 static int faith_clone_destroy(struct ifnet *); 100 101 static struct if_clone faith_cloner = 102 IF_CLONE_INITIALIZER("faith", faith_clone_create, faith_clone_destroy); 103 104 #define FAITHMTU 1500 105 106 static u_int faith_count; 107 108 /* ARGSUSED */ 109 void 110 faithattach(int count) 111 { 112 113 /* 114 * Nothing to do here, initialization is handled by the 115 * module initialization code in faithinit() below). 116 */ 117 } 118 119 static void 120 faithinit(void) 121 { 122 if_clone_attach(&faith_cloner); 123 } 124 125 static int 126 faithdetach(void) 127 { 128 int error = 0; 129 130 if (faith_count != 0) 131 error = EBUSY; 132 133 if (error == 0) 134 if_clone_detach(&faith_cloner); 135 136 return error; 137 } 138 139 static int 140 faith_clone_create(struct if_clone *ifc, int unit) 141 { 142 struct ifnet *ifp; 143 int rv; 144 145 ifp = if_alloc(IFT_FAITH); 146 147 if_initname(ifp, ifc->ifc_name, unit); 148 149 ifp->if_mtu = FAITHMTU; 150 /* Change to BROADCAST experimentaly to announce its prefix. */ 151 ifp->if_flags = /* IFF_LOOPBACK */ IFF_BROADCAST | IFF_MULTICAST; 152 ifp->if_ioctl = faithioctl; 153 ifp->if_output = faithoutput; 154 ifp->if_type = IFT_FAITH; 155 ifp->if_hdrlen = 0; 156 ifp->if_addrlen = 0; 157 ifp->if_dlt = DLT_NULL; 158 rv = if_attach(ifp); 159 if (rv != 0) { 160 if_free(ifp); 161 return rv; 162 } 163 if_alloc_sadl(ifp); 164 bpf_attach(ifp, DLT_NULL, sizeof(u_int)); 165 atomic_inc_uint(&faith_count); 166 return (0); 167 } 168 169 int 170 faith_clone_destroy(struct ifnet *ifp) 171 { 172 173 bpf_detach(ifp); 174 if_detach(ifp); 175 if_free(ifp); 176 177 atomic_dec_uint(&faith_count); 178 return (0); 179 } 180 181 static int 182 faithoutput(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst, 183 const struct rtentry *rt) 184 { 185 pktqueue_t *pktq; 186 size_t pktlen; 187 int s, error; 188 uint32_t af; 189 190 if ((m->m_flags & M_PKTHDR) == 0) 191 panic("faithoutput no HDR"); 192 af = dst->sa_family; 193 /* BPF write needs to be handled specially */ 194 if (af == AF_UNSPEC) { 195 af = *(mtod(m, int *)); 196 m_adj(m, sizeof(int)); 197 } 198 199 bpf_mtap_af(ifp, af, m); 200 201 if (rt && rt->rt_flags & (RTF_REJECT|RTF_BLACKHOLE)) { 202 m_freem(m); 203 return (rt->rt_flags & RTF_BLACKHOLE ? 0 : 204 rt->rt_flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH); 205 } 206 pktlen = m->m_pkthdr.len; 207 ifp->if_opackets++; 208 ifp->if_obytes += pktlen; 209 switch (af) { 210 #ifdef INET 211 case AF_INET: 212 pktq = ip_pktq; 213 break; 214 #endif 215 #ifdef INET6 216 case AF_INET6: 217 pktq = ip6_pktq; 218 break; 219 #endif 220 default: 221 m_freem(m); 222 return EAFNOSUPPORT; 223 } 224 225 /* XXX do we need more sanity checks? */ 226 KASSERT(pktq != NULL); 227 m_set_rcvif(m, ifp); 228 229 s = splnet(); 230 if (__predict_true(pktq_enqueue(pktq, m, 0))) { 231 ifp->if_ipackets++; 232 ifp->if_ibytes += pktlen; 233 error = 0; 234 } else { 235 m_freem(m); 236 error = ENOBUFS; 237 } 238 splx(s); 239 240 return error; 241 } 242 243 /* ARGSUSED */ 244 static void 245 faithrtrequest(int cmd, struct rtentry *rt, 246 const struct rt_addrinfo *info) 247 { 248 if (rt) 249 rt->rt_rmx.rmx_mtu = rt->rt_ifp->if_mtu; /* for ISO */ 250 } 251 252 /* 253 * Process an ioctl request. 254 */ 255 /* ARGSUSED */ 256 static int 257 faithioctl(struct ifnet *ifp, u_long cmd, void *data) 258 { 259 struct ifaddr *ifa; 260 struct ifreq *ifr = (struct ifreq *)data; 261 int error = 0; 262 263 switch (cmd) { 264 265 case SIOCINITIFADDR: 266 ifp->if_flags |= IFF_UP | IFF_RUNNING; 267 ifa = (struct ifaddr *)data; 268 ifa->ifa_rtrequest = faithrtrequest; 269 /* 270 * Everything else is done at a higher level. 271 */ 272 break; 273 274 case SIOCADDMULTI: 275 case SIOCDELMULTI: 276 if (ifr == 0) { 277 error = EAFNOSUPPORT; /* XXX */ 278 break; 279 } 280 switch (ifr->ifr_addr.sa_family) { 281 #ifdef INET 282 case AF_INET: 283 break; 284 #endif 285 #ifdef INET6 286 case AF_INET6: 287 break; 288 #endif 289 290 default: 291 error = EAFNOSUPPORT; 292 break; 293 } 294 break; 295 296 default: 297 if ((error = ifioctl_common(ifp, cmd, data)) == ENETRESET) 298 error = 0; 299 break; 300 } 301 return (error); 302 } 303 304 #ifdef INET6 305 /* 306 * XXX could be slow 307 * XXX could be layer violation to call sys/net from sys/netinet6 308 */ 309 int 310 faithprefix(struct in6_addr *in6) 311 { 312 struct rtentry *rt; 313 struct sockaddr_in6 sin6; 314 int ret; 315 316 if (ip6_keepfaith == 0) 317 return 0; 318 319 memset(&sin6, 0, sizeof(sin6)); 320 sin6.sin6_family = AF_INET6; 321 sin6.sin6_len = sizeof(struct sockaddr_in6); 322 sin6.sin6_addr = *in6; 323 rt = rtalloc1((struct sockaddr *)&sin6, 0); 324 if (rt && rt->rt_ifp && rt->rt_ifp->if_type == IFT_FAITH && 325 (rt->rt_ifp->if_flags & IFF_UP) != 0) 326 ret = 1; 327 else 328 ret = 0; 329 if (rt) 330 rt_unref(rt); 331 return ret; 332 } 333 #endif 334 335 /* 336 * Module infrastructure 337 */ 338 #include "if_module.h" 339 340 IF_MODULE(MODULE_CLASS_DRIVER, faith, "") 341