1 /* $NetBSD: if_faith.c,v 1.59 2018/06/26 06:48:02 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 1.59 2018/06/26 06:48:02 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 #include "ioconf.h" 88 89 static int faithioctl(struct ifnet *, u_long, void *); 90 static int faithoutput(struct ifnet *, struct mbuf *, 91 const struct sockaddr *, const struct rtentry *); 92 static void faithrtrequest(int, struct rtentry *, 93 const struct rt_addrinfo *); 94 95 static int faith_clone_create(struct if_clone *, int); 96 static int faith_clone_destroy(struct ifnet *); 97 98 static struct if_clone faith_cloner = 99 IF_CLONE_INITIALIZER("faith", faith_clone_create, faith_clone_destroy); 100 101 #define FAITHMTU 1500 102 103 static u_int faith_count; 104 105 /* ARGSUSED */ 106 void 107 faithattach(int count) 108 { 109 110 /* 111 * Nothing to do here, initialization is handled by the 112 * module initialization code in faithinit() below). 113 */ 114 } 115 116 static void 117 faithinit(void) 118 { 119 if_clone_attach(&faith_cloner); 120 } 121 122 static int 123 faithdetach(void) 124 { 125 int error = 0; 126 127 if (faith_count != 0) 128 error = EBUSY; 129 130 if (error == 0) 131 if_clone_detach(&faith_cloner); 132 133 return error; 134 } 135 136 static int 137 faith_clone_create(struct if_clone *ifc, int unit) 138 { 139 struct ifnet *ifp; 140 int rv; 141 142 ifp = if_alloc(IFT_FAITH); 143 144 if_initname(ifp, ifc->ifc_name, unit); 145 146 ifp->if_mtu = FAITHMTU; 147 /* Change to BROADCAST experimentaly to announce its prefix. */ 148 ifp->if_flags = /* IFF_LOOPBACK */ IFF_BROADCAST | IFF_MULTICAST; 149 ifp->if_ioctl = faithioctl; 150 ifp->if_output = faithoutput; 151 ifp->if_type = IFT_FAITH; 152 ifp->if_hdrlen = 0; 153 ifp->if_addrlen = 0; 154 ifp->if_dlt = DLT_NULL; 155 rv = if_attach(ifp); 156 if (rv != 0) { 157 if_free(ifp); 158 return rv; 159 } 160 if_alloc_sadl(ifp); 161 bpf_attach(ifp, DLT_NULL, sizeof(u_int)); 162 atomic_inc_uint(&faith_count); 163 return (0); 164 } 165 166 int 167 faith_clone_destroy(struct ifnet *ifp) 168 { 169 170 bpf_detach(ifp); 171 if_detach(ifp); 172 if_free(ifp); 173 174 atomic_dec_uint(&faith_count); 175 return (0); 176 } 177 178 static int 179 faithoutput(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst, 180 const struct rtentry *rt) 181 { 182 pktqueue_t *pktq; 183 size_t pktlen; 184 int s, error; 185 uint32_t af; 186 187 if ((m->m_flags & M_PKTHDR) == 0) 188 panic("faithoutput no HDR"); 189 af = dst->sa_family; 190 /* BPF write needs to be handled specially */ 191 if (af == AF_UNSPEC) { 192 af = *(mtod(m, int *)); 193 m_adj(m, sizeof(int)); 194 } 195 196 bpf_mtap_af(ifp, af, m, BPF_D_OUT); 197 198 if (rt && rt->rt_flags & (RTF_REJECT|RTF_BLACKHOLE)) { 199 m_freem(m); 200 return (rt->rt_flags & RTF_BLACKHOLE ? 0 : 201 rt->rt_flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH); 202 } 203 pktlen = m->m_pkthdr.len; 204 ifp->if_opackets++; 205 ifp->if_obytes += pktlen; 206 switch (af) { 207 #ifdef INET 208 case AF_INET: 209 pktq = ip_pktq; 210 break; 211 #endif 212 #ifdef INET6 213 case AF_INET6: 214 pktq = ip6_pktq; 215 break; 216 #endif 217 default: 218 m_freem(m); 219 return EAFNOSUPPORT; 220 } 221 222 /* XXX do we need more sanity checks? */ 223 KASSERT(pktq != NULL); 224 m_set_rcvif(m, ifp); 225 226 s = splnet(); 227 if (__predict_true(pktq_enqueue(pktq, m, 0))) { 228 ifp->if_ipackets++; 229 ifp->if_ibytes += pktlen; 230 error = 0; 231 } else { 232 m_freem(m); 233 error = ENOBUFS; 234 } 235 splx(s); 236 237 return error; 238 } 239 240 /* ARGSUSED */ 241 static void 242 faithrtrequest(int cmd, struct rtentry *rt, 243 const struct rt_addrinfo *info) 244 { 245 if (rt) 246 rt->rt_rmx.rmx_mtu = rt->rt_ifp->if_mtu; /* for ISO */ 247 } 248 249 /* 250 * Process an ioctl request. 251 */ 252 /* ARGSUSED */ 253 static int 254 faithioctl(struct ifnet *ifp, u_long cmd, void *data) 255 { 256 struct ifaddr *ifa; 257 struct ifreq *ifr = (struct ifreq *)data; 258 int error = 0; 259 260 switch (cmd) { 261 262 case SIOCINITIFADDR: 263 ifa = (struct ifaddr *)data; 264 ifa->ifa_rtrequest = faithrtrequest; 265 ifp->if_flags |= IFF_UP | IFF_RUNNING; 266 /* 267 * Everything else is done at a higher level. 268 */ 269 break; 270 271 case SIOCADDMULTI: 272 case SIOCDELMULTI: 273 if (ifr == 0) { 274 error = EAFNOSUPPORT; /* XXX */ 275 break; 276 } 277 switch (ifr->ifr_addr.sa_family) { 278 #ifdef INET 279 case AF_INET: 280 break; 281 #endif 282 #ifdef INET6 283 case AF_INET6: 284 break; 285 #endif 286 287 default: 288 error = EAFNOSUPPORT; 289 break; 290 } 291 break; 292 293 default: 294 if ((error = ifioctl_common(ifp, cmd, data)) == ENETRESET) 295 error = 0; 296 break; 297 } 298 return (error); 299 } 300 301 #ifdef INET6 302 /* 303 * XXX could be slow 304 * XXX could be layer violation to call sys/net from sys/netinet6 305 */ 306 int 307 faithprefix(struct in6_addr *in6) 308 { 309 struct rtentry *rt; 310 struct sockaddr_in6 sin6; 311 int ret; 312 313 if (ip6_keepfaith == 0) 314 return 0; 315 316 memset(&sin6, 0, sizeof(sin6)); 317 sin6.sin6_family = AF_INET6; 318 sin6.sin6_len = sizeof(struct sockaddr_in6); 319 sin6.sin6_addr = *in6; 320 rt = rtalloc1((struct sockaddr *)&sin6, 0); 321 if (rt && rt->rt_ifp && rt->rt_ifp->if_type == IFT_FAITH && 322 (rt->rt_ifp->if_flags & IFF_UP) != 0) 323 ret = 1; 324 else 325 ret = 0; 326 if (rt) 327 rt_unref(rt); 328 return ret; 329 } 330 #endif 331 332 /* 333 * Module infrastructure 334 */ 335 #include "if_module.h" 336 337 IF_MODULE(MODULE_CLASS_DRIVER, faith, "") 338