1 /* $NetBSD: if_faith.c,v 1.61 2020/01/29 04:18:34 thorpej 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 1.61 2020/01/29 04:18:34 thorpej 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 if_statadd2(ifp, if_opackets, 1, if_obytes, pktlen); 205 switch (af) { 206 #ifdef INET 207 case AF_INET: 208 pktq = ip_pktq; 209 break; 210 #endif 211 #ifdef INET6 212 case AF_INET6: 213 pktq = ip6_pktq; 214 break; 215 #endif 216 default: 217 m_freem(m); 218 return EAFNOSUPPORT; 219 } 220 221 /* XXX do we need more sanity checks? */ 222 KASSERT(pktq != NULL); 223 m_set_rcvif(m, ifp); 224 225 s = splnet(); 226 if (__predict_true(pktq_enqueue(pktq, m, 0))) { 227 if_statadd2(ifp, if_ipackets, 1, if_ibytes, pktlen); 228 error = 0; 229 } else { 230 m_freem(m); 231 error = ENOBUFS; 232 } 233 splx(s); 234 235 return error; 236 } 237 238 /* ARGSUSED */ 239 static void 240 faithrtrequest(int cmd, struct rtentry *rt, 241 const struct rt_addrinfo *info) 242 { 243 if (rt) 244 rt->rt_rmx.rmx_mtu = rt->rt_ifp->if_mtu; /* for ISO */ 245 } 246 247 /* 248 * Process an ioctl request. 249 */ 250 /* ARGSUSED */ 251 static int 252 faithioctl(struct ifnet *ifp, u_long cmd, void *data) 253 { 254 struct ifaddr *ifa; 255 struct ifreq *ifr = (struct ifreq *)data; 256 int error = 0; 257 258 switch (cmd) { 259 260 case SIOCINITIFADDR: 261 ifa = (struct ifaddr *)data; 262 ifa->ifa_rtrequest = faithrtrequest; 263 ifp->if_flags |= IFF_UP | IFF_RUNNING; 264 /* 265 * Everything else is done at a higher level. 266 */ 267 break; 268 269 case SIOCADDMULTI: 270 case SIOCDELMULTI: 271 if (ifr == 0) { 272 error = EAFNOSUPPORT; /* XXX */ 273 break; 274 } 275 switch (ifr->ifr_addr.sa_family) { 276 #ifdef INET 277 case AF_INET: 278 break; 279 #endif 280 #ifdef INET6 281 case AF_INET6: 282 break; 283 #endif 284 285 default: 286 error = EAFNOSUPPORT; 287 break; 288 } 289 break; 290 291 default: 292 if ((error = ifioctl_common(ifp, cmd, data)) == ENETRESET) 293 error = 0; 294 break; 295 } 296 return (error); 297 } 298 299 #ifdef INET6 300 /* 301 * XXX could be slow 302 * XXX could be layer violation to call sys/net from sys/netinet6 303 */ 304 int 305 faithprefix(struct in6_addr *in6) 306 { 307 struct rtentry *rt; 308 struct sockaddr_in6 sin6; 309 int ret; 310 311 if (ip6_keepfaith == 0) 312 return 0; 313 314 memset(&sin6, 0, sizeof(sin6)); 315 sin6.sin6_family = AF_INET6; 316 sin6.sin6_len = sizeof(struct sockaddr_in6); 317 sin6.sin6_addr = *in6; 318 rt = rtalloc1((struct sockaddr *)&sin6, 0); 319 if (rt && rt->rt_ifp && rt->rt_ifp->if_type == IFT_FAITH && 320 (rt->rt_ifp->if_flags & IFF_UP) != 0) 321 ret = 1; 322 else 323 ret = 0; 324 if (rt) 325 rt_unref(rt); 326 return ret; 327 } 328 #endif 329 330 /* 331 * Module infrastructure 332 */ 333 #include "if_module.h" 334 335 IF_MODULE(MODULE_CLASS_DRIVER, faith, NULL) 336