if_loop.c revision 1.87
1 /* $NetBSD: if_loop.c,v 1.87 2016/06/10 13:27:16 ozaki-r Exp $ */ 2 3 /* 4 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the project nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 /* 33 * Copyright (c) 1982, 1986, 1993 34 * The Regents of the University of California. All rights reserved. 35 * 36 * Redistribution and use in source and binary forms, with or without 37 * modification, are permitted provided that the following conditions 38 * are met: 39 * 1. Redistributions of source code must retain the above copyright 40 * notice, this list of conditions and the following disclaimer. 41 * 2. Redistributions in binary form must reproduce the above copyright 42 * notice, this list of conditions and the following disclaimer in the 43 * documentation and/or other materials provided with the distribution. 44 * 3. Neither the name of the University nor the names of its contributors 45 * may be used to endorse or promote products derived from this software 46 * without specific prior written permission. 47 * 48 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 49 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 50 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 51 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 52 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 53 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 54 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 55 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 56 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 57 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 58 * SUCH DAMAGE. 59 * 60 * @(#)if_loop.c 8.2 (Berkeley) 1/9/95 61 */ 62 63 /* 64 * Loopback interface driver for protocol testing and timing. 65 */ 66 67 #include <sys/cdefs.h> 68 __KERNEL_RCSID(0, "$NetBSD: if_loop.c,v 1.87 2016/06/10 13:27:16 ozaki-r Exp $"); 69 70 #ifdef _KERNEL_OPT 71 #include "opt_inet.h" 72 #include "opt_atalk.h" 73 #include "opt_mbuftrace.h" 74 #include "opt_mpls.h" 75 #include "opt_net_mpsafe.h" 76 #endif 77 78 #include <sys/param.h> 79 #include <sys/systm.h> 80 #include <sys/kernel.h> 81 #include <sys/mbuf.h> 82 #include <sys/socket.h> 83 #include <sys/errno.h> 84 #include <sys/ioctl.h> 85 #include <sys/time.h> 86 87 #include <sys/cpu.h> 88 89 #include <net/if.h> 90 #include <net/if_types.h> 91 #include <net/netisr.h> 92 #include <net/route.h> 93 94 #ifdef INET 95 #include <netinet/in.h> 96 #include <netinet/in_systm.h> 97 #include <netinet/in_var.h> 98 #include <netinet/in_offload.h> 99 #include <netinet/ip.h> 100 #endif 101 102 #ifdef INET6 103 #ifndef INET 104 #include <netinet/in.h> 105 #endif 106 #include <netinet6/in6_var.h> 107 #include <netinet6/in6_offload.h> 108 #include <netinet/ip6.h> 109 #endif 110 111 #ifdef MPLS 112 #include <netmpls/mpls.h> 113 #include <netmpls/mpls_var.h> 114 #endif 115 116 #ifdef NETATALK 117 #include <netatalk/at.h> 118 #include <netatalk/at_var.h> 119 #endif 120 121 #include <net/bpf.h> 122 123 #if defined(LARGE_LOMTU) 124 #define LOMTU (131072 + MHLEN + MLEN) 125 #define LOMTU_MAX LOMTU 126 #else 127 #define LOMTU (32768 + MHLEN + MLEN) 128 #define LOMTU_MAX (65536 + MHLEN + MLEN) 129 #endif 130 131 #ifdef ALTQ 132 static void lostart(struct ifnet *); 133 #endif 134 135 static int loop_clone_create(struct if_clone *, int); 136 static int loop_clone_destroy(struct ifnet *); 137 138 static struct if_clone loop_cloner = 139 IF_CLONE_INITIALIZER("lo", loop_clone_create, loop_clone_destroy); 140 141 void 142 loopattach(int n) 143 { 144 145 (void)loop_clone_create(&loop_cloner, 0); /* lo0 always exists */ 146 if_clone_attach(&loop_cloner); 147 } 148 149 static int 150 loop_clone_create(struct if_clone *ifc, int unit) 151 { 152 struct ifnet *ifp; 153 154 ifp = if_alloc(IFT_LOOP); 155 156 if_initname(ifp, ifc->ifc_name, unit); 157 158 ifp->if_mtu = LOMTU; 159 ifp->if_flags = IFF_LOOPBACK | IFF_MULTICAST | IFF_RUNNING; 160 ifp->if_ioctl = loioctl; 161 ifp->if_output = looutput; 162 #ifdef ALTQ 163 ifp->if_start = lostart; 164 #endif 165 ifp->if_type = IFT_LOOP; 166 ifp->if_hdrlen = 0; 167 ifp->if_addrlen = 0; 168 ifp->if_dlt = DLT_NULL; 169 IFQ_SET_READY(&ifp->if_snd); 170 if (unit == 0) 171 lo0ifp = ifp; 172 if_attach(ifp); 173 if_alloc_sadl(ifp); 174 bpf_attach(ifp, DLT_NULL, sizeof(u_int)); 175 #ifdef MBUFTRACE 176 ifp->if_mowner = malloc(sizeof(struct mowner), M_DEVBUF, 177 M_WAITOK | M_ZERO); 178 strlcpy(ifp->if_mowner->mo_name, ifp->if_xname, 179 sizeof(ifp->if_mowner->mo_name)); 180 MOWNER_ATTACH(ifp->if_mowner); 181 #endif 182 183 return (0); 184 } 185 186 static int 187 loop_clone_destroy(struct ifnet *ifp) 188 { 189 190 if (ifp == lo0ifp) 191 return (EPERM); 192 193 #ifdef MBUFTRACE 194 MOWNER_DETACH(ifp->if_mowner); 195 free(ifp->if_mowner, M_DEVBUF); 196 #endif 197 198 bpf_detach(ifp); 199 if_detach(ifp); 200 201 if_free(ifp); 202 203 return (0); 204 } 205 206 int 207 looutput(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst, 208 const struct rtentry *rt) 209 { 210 pktqueue_t *pktq = NULL; 211 struct ifqueue *ifq = NULL; 212 int s, isr = -1; 213 int csum_flags; 214 size_t pktlen; 215 216 MCLAIM(m, ifp->if_mowner); 217 #ifndef NET_MPSAFE 218 KASSERT(KERNEL_LOCKED_P()); 219 #endif 220 221 if ((m->m_flags & M_PKTHDR) == 0) 222 panic("looutput: no header mbuf"); 223 if (ifp->if_flags & IFF_LOOPBACK) 224 bpf_mtap_af(ifp, dst->sa_family, m); 225 m_set_rcvif(m, ifp); 226 227 if (rt && rt->rt_flags & (RTF_REJECT|RTF_BLACKHOLE)) { 228 m_freem(m); 229 return (rt->rt_flags & RTF_BLACKHOLE ? 0 : 230 rt->rt_flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH); 231 } 232 233 pktlen = m->m_pkthdr.len; 234 ifp->if_opackets++; 235 ifp->if_obytes += pktlen; 236 237 #ifdef ALTQ 238 /* 239 * ALTQ on the loopback interface is just for debugging. It's 240 * used only for loopback interfaces, not for a simplex interface. 241 */ 242 if ((ALTQ_IS_ENABLED(&ifp->if_snd) || TBR_IS_ENABLED(&ifp->if_snd)) && 243 ifp->if_start == lostart) { 244 int error; 245 246 /* 247 * If the queueing discipline needs packet classification, 248 * do it before prepending the link headers. 249 */ 250 IFQ_CLASSIFY(&ifp->if_snd, m, dst->sa_family); 251 252 M_PREPEND(m, sizeof(uint32_t), M_DONTWAIT); 253 if (m == NULL) 254 return (ENOBUFS); 255 *(mtod(m, uint32_t *)) = dst->sa_family; 256 257 error = ifp->if_transmit(ifp, m); 258 return (error); 259 } 260 #endif /* ALTQ */ 261 262 m_tag_delete_nonpersistent(m); 263 264 #ifdef MPLS 265 if (rt != NULL && rt_gettag(rt) != NULL && 266 rt_gettag(rt)->sa_family == AF_MPLS && 267 (m->m_flags & (M_MCAST | M_BCAST)) == 0) { 268 union mpls_shim msh; 269 msh.s_addr = MPLS_GETSADDR(rt); 270 if (msh.shim.label != MPLS_LABEL_IMPLNULL) { 271 ifq = &mplsintrq; 272 isr = NETISR_MPLS; 273 } 274 } 275 if (isr != NETISR_MPLS) 276 #endif 277 switch (dst->sa_family) { 278 279 #ifdef INET 280 case AF_INET: 281 csum_flags = m->m_pkthdr.csum_flags; 282 KASSERT((csum_flags & ~(M_CSUM_IPv4|M_CSUM_UDPv4)) == 0); 283 if (csum_flags != 0 && IN_LOOPBACK_NEED_CHECKSUM(csum_flags)) { 284 ip_undefer_csum(m, 0, csum_flags); 285 } 286 m->m_pkthdr.csum_flags = 0; 287 pktq = ip_pktq; 288 break; 289 #endif 290 #ifdef INET6 291 case AF_INET6: 292 csum_flags = m->m_pkthdr.csum_flags; 293 KASSERT((csum_flags & ~M_CSUM_UDPv6) == 0); 294 if (csum_flags != 0 && 295 IN6_LOOPBACK_NEED_CHECKSUM(csum_flags)) { 296 ip6_undefer_csum(m, 0, csum_flags); 297 } 298 m->m_pkthdr.csum_flags = 0; 299 m->m_flags |= M_LOOP; 300 pktq = ip6_pktq; 301 break; 302 #endif 303 #ifdef NETATALK 304 case AF_APPLETALK: 305 ifq = &atintrq2; 306 isr = NETISR_ATALK; 307 break; 308 #endif 309 default: 310 printf("%s: can't handle af%d\n", ifp->if_xname, 311 dst->sa_family); 312 m_freem(m); 313 return (EAFNOSUPPORT); 314 } 315 316 s = splnet(); 317 if (__predict_true(pktq)) { 318 int error = 0; 319 320 if (__predict_true(pktq_enqueue(pktq, m, 0))) { 321 ifp->if_ipackets++; 322 ifp->if_ibytes += pktlen; 323 } else { 324 m_freem(m); 325 error = ENOBUFS; 326 } 327 splx(s); 328 return error; 329 } 330 if (IF_QFULL(ifq)) { 331 IF_DROP(ifq); 332 m_freem(m); 333 splx(s); 334 return (ENOBUFS); 335 } 336 IF_ENQUEUE(ifq, m); 337 schednetisr(isr); 338 ifp->if_ipackets++; 339 ifp->if_ibytes += m->m_pkthdr.len; 340 splx(s); 341 return (0); 342 } 343 344 #ifdef ALTQ 345 static void 346 lostart(struct ifnet *ifp) 347 { 348 for (;;) { 349 pktqueue_t *pktq = NULL; 350 struct ifqueue *ifq = NULL; 351 struct mbuf *m; 352 size_t pktlen; 353 uint32_t af; 354 int s, isr = 0; 355 356 IFQ_DEQUEUE(&ifp->if_snd, m); 357 if (m == NULL) 358 return; 359 360 af = *(mtod(m, uint32_t *)); 361 m_adj(m, sizeof(uint32_t)); 362 363 switch (af) { 364 #ifdef INET 365 case AF_INET: 366 pktq = ip_pktq; 367 break; 368 #endif 369 #ifdef INET6 370 case AF_INET6: 371 m->m_flags |= M_LOOP; 372 pktq = ip6_pktq; 373 break; 374 #endif 375 #ifdef NETATALK 376 case AF_APPLETALK: 377 ifq = &atintrq2; 378 isr = NETISR_ATALK; 379 break; 380 #endif 381 default: 382 printf("%s: can't handle af%d\n", ifp->if_xname, af); 383 m_freem(m); 384 return; 385 } 386 pktlen = m->m_pkthdr.len; 387 388 s = splnet(); 389 if (__predict_true(pktq)) { 390 if (__predict_false(pktq_enqueue(pktq, m, 0))) { 391 m_freem(m); 392 splx(s); 393 return; 394 } 395 ifp->if_ipackets++; 396 ifp->if_ibytes += pktlen; 397 splx(s); 398 continue; 399 } 400 if (IF_QFULL(ifq)) { 401 IF_DROP(ifq); 402 splx(s); 403 m_freem(m); 404 return; 405 } 406 IF_ENQUEUE(ifq, m); 407 schednetisr(isr); 408 ifp->if_ipackets++; 409 ifp->if_ibytes += pktlen; 410 splx(s); 411 } 412 } 413 #endif /* ALTQ */ 414 415 /* ARGSUSED */ 416 void 417 lortrequest(int cmd, struct rtentry *rt, 418 const struct rt_addrinfo *info) 419 { 420 421 if (rt) 422 rt->rt_rmx.rmx_mtu = lo0ifp->if_mtu; 423 } 424 425 /* 426 * Process an ioctl request. 427 */ 428 /* ARGSUSED */ 429 int 430 loioctl(struct ifnet *ifp, u_long cmd, void *data) 431 { 432 struct ifaddr *ifa; 433 struct ifreq *ifr = data; 434 int error = 0; 435 436 switch (cmd) { 437 438 case SIOCINITIFADDR: 439 ifp->if_flags |= IFF_UP; 440 ifa = (struct ifaddr *)data; 441 if (ifa != NULL) 442 ifa->ifa_rtrequest = lortrequest; 443 /* 444 * Everything else is done at a higher level. 445 */ 446 break; 447 448 case SIOCSIFMTU: 449 if ((unsigned)ifr->ifr_mtu > LOMTU_MAX) 450 error = EINVAL; 451 else if ((error = ifioctl_common(ifp, cmd, data)) == ENETRESET){ 452 error = 0; 453 } 454 break; 455 456 case SIOCADDMULTI: 457 case SIOCDELMULTI: 458 if (ifr == NULL) { 459 error = EAFNOSUPPORT; /* XXX */ 460 break; 461 } 462 switch (ifreq_getaddr(cmd, ifr)->sa_family) { 463 464 #ifdef INET 465 case AF_INET: 466 break; 467 #endif 468 #ifdef INET6 469 case AF_INET6: 470 break; 471 #endif 472 473 default: 474 error = EAFNOSUPPORT; 475 break; 476 } 477 break; 478 479 default: 480 error = ifioctl_common(ifp, cmd, data); 481 } 482 return (error); 483 } 484
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