if_loop.c revision 1.84
1 /* $NetBSD: if_loop.c,v 1.84 2016/04/20 09:01:04 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 1.84 2016/04/20 09:01:04 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_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 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->m_pkthdr.rcvif = 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 s = splnet(); 258 IFQ_ENQUEUE(&ifp->if_snd, m, error); 259 (*ifp->if_start)(ifp); 260 splx(s); 261 return (error); 262 } 263 #endif /* ALTQ */ 264 265 m_tag_delete_nonpersistent(m); 266 267 #ifdef MPLS 268 if (rt != NULL && rt_gettag(rt) != NULL && 269 rt_gettag(rt)->sa_family == AF_MPLS && 270 (m->m_flags & (M_MCAST | M_BCAST)) == 0) { 271 union mpls_shim msh; 272 msh.s_addr = MPLS_GETSADDR(rt); 273 if (msh.shim.label != MPLS_LABEL_IMPLNULL) { 274 ifq = &mplsintrq; 275 isr = NETISR_MPLS; 276 } 277 } 278 if (isr != NETISR_MPLS) 279 #endif 280 switch (dst->sa_family) { 281 282 #ifdef INET 283 case AF_INET: 284 csum_flags = m->m_pkthdr.csum_flags; 285 KASSERT((csum_flags & ~(M_CSUM_IPv4|M_CSUM_UDPv4)) == 0); 286 if (csum_flags != 0 && IN_LOOPBACK_NEED_CHECKSUM(csum_flags)) { 287 ip_undefer_csum(m, 0, csum_flags); 288 } 289 m->m_pkthdr.csum_flags = 0; 290 pktq = ip_pktq; 291 break; 292 #endif 293 #ifdef INET6 294 case AF_INET6: 295 csum_flags = m->m_pkthdr.csum_flags; 296 KASSERT((csum_flags & ~M_CSUM_UDPv6) == 0); 297 if (csum_flags != 0 && 298 IN6_LOOPBACK_NEED_CHECKSUM(csum_flags)) { 299 ip6_undefer_csum(m, 0, csum_flags); 300 } 301 m->m_pkthdr.csum_flags = 0; 302 m->m_flags |= M_LOOP; 303 pktq = ip6_pktq; 304 break; 305 #endif 306 #ifdef NETATALK 307 case AF_APPLETALK: 308 ifq = &atintrq2; 309 isr = NETISR_ATALK; 310 break; 311 #endif 312 default: 313 printf("%s: can't handle af%d\n", ifp->if_xname, 314 dst->sa_family); 315 m_freem(m); 316 return (EAFNOSUPPORT); 317 } 318 319 s = splnet(); 320 if (__predict_true(pktq)) { 321 int 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 return error; 332 } 333 if (IF_QFULL(ifq)) { 334 IF_DROP(ifq); 335 m_freem(m); 336 splx(s); 337 return (ENOBUFS); 338 } 339 IF_ENQUEUE(ifq, m); 340 schednetisr(isr); 341 ifp->if_ipackets++; 342 ifp->if_ibytes += m->m_pkthdr.len; 343 splx(s); 344 return (0); 345 } 346 347 #ifdef ALTQ 348 static void 349 lostart(struct ifnet *ifp) 350 { 351 for (;;) { 352 pktqueue_t *pktq = NULL; 353 struct ifqueue *ifq = NULL; 354 struct mbuf *m; 355 size_t pktlen; 356 uint32_t af; 357 int s, isr = 0; 358 359 IFQ_DEQUEUE(&ifp->if_snd, m); 360 if (m == NULL) 361 return; 362 363 af = *(mtod(m, uint32_t *)); 364 m_adj(m, sizeof(uint32_t)); 365 366 switch (af) { 367 #ifdef INET 368 case AF_INET: 369 pktq = ip_pktq; 370 break; 371 #endif 372 #ifdef INET6 373 case AF_INET6: 374 m->m_flags |= M_LOOP; 375 pktq = ip6_pktq; 376 break; 377 #endif 378 #ifdef NETATALK 379 case AF_APPLETALK: 380 ifq = &atintrq2; 381 isr = NETISR_ATALK; 382 break; 383 #endif 384 default: 385 printf("%s: can't handle af%d\n", ifp->if_xname, af); 386 m_freem(m); 387 return; 388 } 389 pktlen = m->m_pkthdr.len; 390 391 s = splnet(); 392 if (__predict_true(pktq)) { 393 if (__predict_false(pktq_enqueue(pktq, m, 0))) { 394 m_freem(m); 395 splx(s); 396 return; 397 } 398 ifp->if_ipackets++; 399 ifp->if_ibytes += pktlen; 400 splx(s); 401 continue; 402 } 403 if (IF_QFULL(ifq)) { 404 IF_DROP(ifq); 405 splx(s); 406 m_freem(m); 407 return; 408 } 409 IF_ENQUEUE(ifq, m); 410 schednetisr(isr); 411 ifp->if_ipackets++; 412 ifp->if_ibytes += pktlen; 413 splx(s); 414 } 415 } 416 #endif /* ALTQ */ 417 418 /* ARGSUSED */ 419 void 420 lortrequest(int cmd, struct rtentry *rt, 421 const struct rt_addrinfo *info) 422 { 423 424 if (rt) 425 rt->rt_rmx.rmx_mtu = lo0ifp->if_mtu; 426 } 427 428 /* 429 * Process an ioctl request. 430 */ 431 /* ARGSUSED */ 432 int 433 loioctl(struct ifnet *ifp, u_long cmd, void *data) 434 { 435 struct ifaddr *ifa; 436 struct ifreq *ifr = data; 437 int error = 0; 438 439 switch (cmd) { 440 441 case SIOCINITIFADDR: 442 ifp->if_flags |= IFF_UP; 443 ifa = (struct ifaddr *)data; 444 if (ifa != NULL) 445 ifa->ifa_rtrequest = lortrequest; 446 /* 447 * Everything else is done at a higher level. 448 */ 449 break; 450 451 case SIOCSIFMTU: 452 if ((unsigned)ifr->ifr_mtu > LOMTU_MAX) 453 error = EINVAL; 454 else if ((error = ifioctl_common(ifp, cmd, data)) == ENETRESET){ 455 error = 0; 456 } 457 break; 458 459 case SIOCADDMULTI: 460 case SIOCDELMULTI: 461 if (ifr == NULL) { 462 error = EAFNOSUPPORT; /* XXX */ 463 break; 464 } 465 switch (ifreq_getaddr(cmd, ifr)->sa_family) { 466 467 #ifdef INET 468 case AF_INET: 469 break; 470 #endif 471 #ifdef INET6 472 case AF_INET6: 473 break; 474 #endif 475 476 default: 477 error = EAFNOSUPPORT; 478 break; 479 } 480 break; 481 482 default: 483 error = ifioctl_common(ifp, cmd, data); 484 } 485 return (error); 486 } 487
Indexes created Tue Sep 23 14:10:03 GMT 2025