if_loop.c revision 1.89
1 /* $NetBSD: if_loop.c,v 1.89 2016/06/22 10:44:32 knakahara 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 1.89 2016/06/22 10:44:32 knakahara 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_extflags = IFEF_OUTPUT_MPSAFE; 161 ifp->if_ioctl = loioctl; 162 ifp->if_output = looutput; 163 #ifdef ALTQ 164 ifp->if_start = lostart; 165 #endif 166 ifp->if_type = IFT_LOOP; 167 ifp->if_hdrlen = 0; 168 ifp->if_addrlen = 0; 169 ifp->if_dlt = DLT_NULL; 170 IFQ_SET_READY(&ifp->if_snd); 171 if (unit == 0) 172 lo0ifp = ifp; 173 if_attach(ifp); 174 if_alloc_sadl(ifp); 175 bpf_attach(ifp, DLT_NULL, sizeof(u_int)); 176 #ifdef MBUFTRACE 177 ifp->if_mowner = malloc(sizeof(struct mowner), M_DEVBUF, 178 M_WAITOK | M_ZERO); 179 strlcpy(ifp->if_mowner->mo_name, ifp->if_xname, 180 sizeof(ifp->if_mowner->mo_name)); 181 MOWNER_ATTACH(ifp->if_mowner); 182 #endif 183 184 return (0); 185 } 186 187 static int 188 loop_clone_destroy(struct ifnet *ifp) 189 { 190 191 if (ifp == lo0ifp) 192 return (EPERM); 193 194 #ifdef MBUFTRACE 195 MOWNER_DETACH(ifp->if_mowner); 196 free(ifp->if_mowner, M_DEVBUF); 197 #endif 198 199 bpf_detach(ifp); 200 if_detach(ifp); 201 202 if_free(ifp); 203 204 return (0); 205 } 206 207 int 208 looutput(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst, 209 const struct rtentry *rt) 210 { 211 pktqueue_t *pktq = NULL; 212 struct ifqueue *ifq = NULL; 213 int s, isr = -1; 214 int csum_flags; 215 int error = 0; 216 size_t pktlen; 217 218 MCLAIM(m, ifp->if_mowner); 219 220 KERNEL_LOCK(1, NULL); 221 222 if ((m->m_flags & M_PKTHDR) == 0) 223 panic("looutput: no header mbuf"); 224 if (ifp->if_flags & IFF_LOOPBACK) 225 bpf_mtap_af(ifp, dst->sa_family, m); 226 m_set_rcvif(m, ifp); 227 228 if (rt && rt->rt_flags & (RTF_REJECT|RTF_BLACKHOLE)) { 229 m_freem(m); 230 error = (rt->rt_flags & RTF_BLACKHOLE ? 0 : 231 rt->rt_flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH); 232 goto out; 233 } 234 235 pktlen = m->m_pkthdr.len; 236 ifp->if_opackets++; 237 ifp->if_obytes += pktlen; 238 239 #ifdef ALTQ 240 /* 241 * ALTQ on the loopback interface is just for debugging. It's 242 * used only for loopback interfaces, not for a simplex interface. 243 */ 244 if ((ALTQ_IS_ENABLED(&ifp->if_snd) || TBR_IS_ENABLED(&ifp->if_snd)) && 245 ifp->if_start == lostart) { 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 error = ENOBUFS; 255 goto out; 256 } 257 *(mtod(m, uint32_t *)) = dst->sa_family; 258 259 error = if_transmit_lock(ifp, m); 260 goto out; 261 } 262 #endif /* ALTQ */ 263 264 m_tag_delete_nonpersistent(m); 265 266 #ifdef MPLS 267 if (rt != NULL && rt_gettag(rt) != NULL && 268 rt_gettag(rt)->sa_family == AF_MPLS && 269 (m->m_flags & (M_MCAST | M_BCAST)) == 0) { 270 union mpls_shim msh; 271 msh.s_addr = MPLS_GETSADDR(rt); 272 if (msh.shim.label != MPLS_LABEL_IMPLNULL) { 273 ifq = &mplsintrq; 274 isr = NETISR_MPLS; 275 } 276 } 277 if (isr != NETISR_MPLS) 278 #endif 279 switch (dst->sa_family) { 280 281 #ifdef INET 282 case AF_INET: 283 csum_flags = m->m_pkthdr.csum_flags; 284 KASSERT((csum_flags & ~(M_CSUM_IPv4|M_CSUM_UDPv4)) == 0); 285 if (csum_flags != 0 && IN_LOOPBACK_NEED_CHECKSUM(csum_flags)) { 286 ip_undefer_csum(m, 0, csum_flags); 287 } 288 m->m_pkthdr.csum_flags = 0; 289 pktq = ip_pktq; 290 break; 291 #endif 292 #ifdef INET6 293 case AF_INET6: 294 csum_flags = m->m_pkthdr.csum_flags; 295 KASSERT((csum_flags & ~M_CSUM_UDPv6) == 0); 296 if (csum_flags != 0 && 297 IN6_LOOPBACK_NEED_CHECKSUM(csum_flags)) { 298 ip6_undefer_csum(m, 0, csum_flags); 299 } 300 m->m_pkthdr.csum_flags = 0; 301 m->m_flags |= M_LOOP; 302 pktq = ip6_pktq; 303 break; 304 #endif 305 #ifdef NETATALK 306 case AF_APPLETALK: 307 ifq = &atintrq2; 308 isr = NETISR_ATALK; 309 break; 310 #endif 311 default: 312 printf("%s: can't handle af%d\n", ifp->if_xname, 313 dst->sa_family); 314 m_freem(m); 315 error = EAFNOSUPPORT; 316 goto out; 317 } 318 319 s = splnet(); 320 if (__predict_true(pktq)) { 321 error = 0; 322 323 if (__predict_true(pktq_enqueue(pktq, m, 0))) { 324 ifp->if_ipackets++; 325 ifp->if_ibytes += pktlen; 326 } else { 327 m_freem(m); 328 error = ENOBUFS; 329 } 330 splx(s); 331 goto out; 332 } 333 if (IF_QFULL(ifq)) { 334 IF_DROP(ifq); 335 m_freem(m); 336 splx(s); 337 error = ENOBUFS; 338 goto out; 339 } 340 IF_ENQUEUE(ifq, m); 341 schednetisr(isr); 342 ifp->if_ipackets++; 343 ifp->if_ibytes += m->m_pkthdr.len; 344 splx(s); 345 out: 346 KERNEL_UNLOCK_ONE(NULL); 347 return error; 348 } 349 350 #ifdef ALTQ 351 static void 352 lostart(struct ifnet *ifp) 353 { 354 for (;;) { 355 pktqueue_t *pktq = NULL; 356 struct ifqueue *ifq = NULL; 357 struct mbuf *m; 358 size_t pktlen; 359 uint32_t af; 360 int s, isr = 0; 361 362 IFQ_DEQUEUE(&ifp->if_snd, m); 363 if (m == NULL) 364 return; 365 366 af = *(mtod(m, uint32_t *)); 367 m_adj(m, sizeof(uint32_t)); 368 369 switch (af) { 370 #ifdef INET 371 case AF_INET: 372 pktq = ip_pktq; 373 break; 374 #endif 375 #ifdef INET6 376 case AF_INET6: 377 m->m_flags |= M_LOOP; 378 pktq = ip6_pktq; 379 break; 380 #endif 381 #ifdef NETATALK 382 case AF_APPLETALK: 383 ifq = &atintrq2; 384 isr = NETISR_ATALK; 385 break; 386 #endif 387 default: 388 printf("%s: can't handle af%d\n", ifp->if_xname, af); 389 m_freem(m); 390 return; 391 } 392 pktlen = m->m_pkthdr.len; 393 394 s = splnet(); 395 if (__predict_true(pktq)) { 396 if (__predict_false(pktq_enqueue(pktq, m, 0))) { 397 m_freem(m); 398 splx(s); 399 return; 400 } 401 ifp->if_ipackets++; 402 ifp->if_ibytes += pktlen; 403 splx(s); 404 continue; 405 } 406 if (IF_QFULL(ifq)) { 407 IF_DROP(ifq); 408 splx(s); 409 m_freem(m); 410 return; 411 } 412 IF_ENQUEUE(ifq, m); 413 schednetisr(isr); 414 ifp->if_ipackets++; 415 ifp->if_ibytes += pktlen; 416 splx(s); 417 } 418 } 419 #endif /* ALTQ */ 420 421 /* ARGSUSED */ 422 void 423 lortrequest(int cmd, struct rtentry *rt, 424 const struct rt_addrinfo *info) 425 { 426 427 if (rt) 428 rt->rt_rmx.rmx_mtu = lo0ifp->if_mtu; 429 } 430 431 /* 432 * Process an ioctl request. 433 */ 434 /* ARGSUSED */ 435 int 436 loioctl(struct ifnet *ifp, u_long cmd, void *data) 437 { 438 struct ifaddr *ifa; 439 struct ifreq *ifr = data; 440 int error = 0; 441 442 switch (cmd) { 443 444 case SIOCINITIFADDR: 445 ifp->if_flags |= IFF_UP; 446 ifa = (struct ifaddr *)data; 447 if (ifa != NULL) 448 ifa->ifa_rtrequest = lortrequest; 449 /* 450 * Everything else is done at a higher level. 451 */ 452 break; 453 454 case SIOCSIFMTU: 455 if ((unsigned)ifr->ifr_mtu > LOMTU_MAX) 456 error = EINVAL; 457 else if ((error = ifioctl_common(ifp, cmd, data)) == ENETRESET){ 458 error = 0; 459 } 460 break; 461 462 case SIOCADDMULTI: 463 case SIOCDELMULTI: 464 if (ifr == NULL) { 465 error = EAFNOSUPPORT; /* XXX */ 466 break; 467 } 468 switch (ifreq_getaddr(cmd, ifr)->sa_family) { 469 470 #ifdef INET 471 case AF_INET: 472 break; 473 #endif 474 #ifdef INET6 475 case AF_INET6: 476 break; 477 #endif 478 479 default: 480 error = EAFNOSUPPORT; 481 break; 482 } 483 break; 484 485 default: 486 error = ifioctl_common(ifp, cmd, data); 487 } 488 return (error); 489 } 490
Indexes created Tue Sep 23 07:09:52 GMT 2025