sys/net/if_loop.c

   1 /*      $NetBSD: if_loop.c,v 1.69 2008/10/24 17:07:33 dyoung 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 1.69 2008/10/24 17:07:33 dyoung Exp $");
  69
  70 #include "opt_inet.h"
  71 #include "opt_atalk.h"
  72 #include "opt_iso.h"
  73 #include "opt_ipx.h"
  74 #include "opt_mbuftrace.h"
  75
  76 #include "bpfilter.h"
  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/ip.h>
  99 #endif
 100
 101 #ifdef INET6
 102 #ifndef INET
 103 #include <netinet/in.h>
 104 #endif
 105 #include <netinet6/in6_var.h>
 106 #include <netinet/ip6.h>
 107 #endif
 108
 109
 110 #ifdef IPX
 111 #include <netipx/ipx.h>
 112 #include <netipx/ipx_if.h>
 113 #endif
 114
 115 #ifdef ISO
 116 #include <netiso/iso.h>
 117 #include <netiso/iso_var.h>
 118 #endif
 119
 120 #ifdef NETATALK
 121 #include <netatalk/at.h>
 122 #include <netatalk/at_var.h>
 123 #endif
 124
 125 #if NBPFILTER > 0
 126 #include <net/bpf.h>
 127 #endif
 128
 129 #if defined(LARGE_LOMTU)
 130 #define LOMTU   (131072 +  MHLEN + MLEN)
 131 #define LOMTU_MAX LOMTU
 132 #else
 133 #define LOMTU   (32768 +  MHLEN + MLEN)
 134 #define LOMTU_MAX       (65536 +  MHLEN + MLEN)
 135 #endif
 136
 137 #ifdef ALTQ
 138 static void     lostart(struct ifnet *);
 139 #endif
 140
 141 static int      loop_clone_create(struct if_clone *, int);
 142 static int      loop_clone_destroy(struct ifnet *);
 143
 144 static struct if_clone loop_cloner =
 145     IF_CLONE_INITIALIZER("lo", loop_clone_create, loop_clone_destroy);
 146
 147 void
 148 loopattach(int n)
 149 {
 150
 151         (void)loop_clone_create(&loop_cloner, 0);       /* lo0 always exists */
 152         if_clone_attach(&loop_cloner);
 153 }
 154
 155 static int
 156 loop_clone_create(struct if_clone *ifc, int unit)
 157 {
 158         struct ifnet *ifp;
 159
 160         ifp = if_alloc(IFT_LOOP);
 161
 162         if_initname(ifp, ifc->ifc_name, unit);
 163
 164         ifp->if_mtu = LOMTU;
 165         ifp->if_flags = IFF_LOOPBACK | IFF_MULTICAST | IFF_RUNNING;
 166         ifp->if_ioctl = loioctl;
 167         ifp->if_output = looutput;
 168 #ifdef ALTQ
 169         ifp->if_start = lostart;
 170 #endif
 171         ifp->if_type = IFT_LOOP;
 172         ifp->if_hdrlen = 0;
 173         ifp->if_addrlen = 0;
 174         ifp->if_dlt = DLT_NULL;
 175         IFQ_SET_READY(&ifp->if_snd);
 176         if (unit == 0)
 177                 lo0ifp = ifp;
 178         if_attach(ifp);
 179         if_alloc_sadl(ifp);
 180 #if NBPFILTER > 0
 181         bpfattach(ifp, DLT_NULL, sizeof(u_int));
 182 #endif
 183 #ifdef MBUFTRACE
 184         ifp->if_mowner = malloc(sizeof(struct mowner), M_DEVBUF,
 185             M_WAITOK | M_ZERO);
 186         strlcpy(ifp->if_mowner->mo_name, ifp->if_xname,
 187             sizeof(ifp->if_mowner->mo_name));
 188         MOWNER_ATTACH(ifp->if_mowner);
 189 #endif
 190
 191         return (0);
 192 }
 193
 194 static int
 195 loop_clone_destroy(struct ifnet *ifp)
 196 {
 197
 198         if (ifp == lo0ifp)
 199                 return (EPERM);
 200
 201 #ifdef MBUFTRACE
 202         MOWNER_DETACH(ifp->if_mowner);
 203         free(ifp->if_mowner, M_DEVBUF);
 204 #endif
 205
 206 #if NBPFILTER > 0
 207         bpfdetach(ifp);
 208 #endif
 209         if_detach(ifp);
 210
 211         free(ifp, M_DEVBUF);
 212
 213         return (0);
 214 }
 215
 216 int
 217 looutput(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst,
 218     struct rtentry *rt)
 219 {
 220         int s, isr;
 221         struct ifqueue *ifq = NULL;
 222
 223         MCLAIM(m, ifp->if_mowner);
 224         if ((m->m_flags & M_PKTHDR) == 0)
 225                 panic("looutput: no header mbuf");
 226 #if NBPFILTER > 0
 227         if (ifp->if_bpf && (ifp->if_flags & IFF_LOOPBACK))
 228                 bpf_mtap_af(ifp->if_bpf, dst->sa_family, m);
 229 #endif
 230         m->m_pkthdr.rcvif = ifp;
 231
 232         if (rt && rt->rt_flags & (RTF_REJECT|RTF_BLACKHOLE)) {
 233                 m_freem(m);
 234                 return (rt->rt_flags & RTF_BLACKHOLE ? 0 :
 235                         rt->rt_flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH);
 236         }
 237
 238         ifp->if_opackets++;
 239         ifp->if_obytes += m->m_pkthdr.len;
 240
 241 #ifdef ALTQ
 242         /*
 243          * ALTQ on the loopback interface is just for debugging.  It's
 244          * used only for loopback interfaces, not for a simplex interface.
 245          */
 246         if ((ALTQ_IS_ENABLED(&ifp->if_snd) || TBR_IS_ENABLED(&ifp->if_snd)) &&
 247             ifp->if_start == lostart) {
 248                 struct altq_pktattr pktattr;
 249                 int error;
 250
 251                 /*
 252                  * If the queueing discipline needs packet classification,
 253                  * do it before prepending the link headers.
 254                  */
 255                 IFQ_CLASSIFY(&ifp->if_snd, m, dst->sa_family, &pktattr);
 256
 257                 M_PREPEND(m, sizeof(uint32_t), M_DONTWAIT);
 258                 if (m == NULL)
 259                         return (ENOBUFS);
 260                 *(mtod(m, uint32_t *)) = dst->sa_family;
 261
 262                 s = splnet();
 263                 IFQ_ENQUEUE(&ifp->if_snd, m, &pktattr, error);
 264                 (*ifp->if_start)(ifp);
 265                 splx(s);
 266                 return (error);
 267         }
 268 #endif /* ALTQ */
 269
 270         m_tag_delete_nonpersistent(m);
 271
 272         switch (dst->sa_family) {
 273
 274 #ifdef INET
 275         case AF_INET:
 276                 ifq = &ipintrq;
 277                 isr = NETISR_IP;
 278                 break;
 279 #endif
 280 #ifdef INET6
 281         case AF_INET6:
 282                 m->m_flags |= M_LOOP;
 283                 ifq = &ip6intrq;
 284                 isr = NETISR_IPV6;
 285                 break;
 286 #endif
 287 #ifdef ISO
 288         case AF_ISO:
 289                 ifq = &clnlintrq;
 290                 isr = NETISR_ISO;
 291                 break;
 292 #endif
 293 #ifdef IPX
 294         case AF_IPX:
 295                 ifq = &ipxintrq;
 296                 isr = NETISR_IPX;
 297                 break;
 298 #endif
 299 #ifdef NETATALK
 300         case AF_APPLETALK:
 301                 ifq = &atintrq2;
 302                 isr = NETISR_ATALK;
 303                 break;
 304 #endif
 305         default:
 306                 printf("%s: can't handle af%d\n", ifp->if_xname,
 307                     dst->sa_family);
 308                 m_freem(m);
 309                 return (EAFNOSUPPORT);
 310         }
 311         s = splnet();
 312         if (IF_QFULL(ifq)) {
 313                 IF_DROP(ifq);
 314                 m_freem(m);
 315                 splx(s);
 316                 return (ENOBUFS);
 317         }
 318         IF_ENQUEUE(ifq, m);
 319         schednetisr(isr);
 320         ifp->if_ipackets++;
 321         ifp->if_ibytes += m->m_pkthdr.len;
 322         splx(s);
 323         return (0);
 324 }
 325
 326 #ifdef ALTQ
 327 static void
 328 lostart(struct ifnet *ifp)
 329 {
 330         struct ifqueue *ifq;
 331         struct mbuf *m;
 332         uint32_t af;
 333         int s, isr;
 334
 335         for (;;) {
 336                 IFQ_DEQUEUE(&ifp->if_snd, m);
 337                 if (m == NULL)
 338                         return;
 339
 340                 af = *(mtod(m, uint32_t *));
 341                 m_adj(m, sizeof(uint32_t));
 342
 343                 switch (af) {
 344 #ifdef INET
 345                 case AF_INET:
 346                         ifq = &ipintrq;
 347                         isr = NETISR_IP;
 348                         break;
 349 #endif
 350 #ifdef INET6
 351                 case AF_INET6:
 352                         m->m_flags |= M_LOOP;
 353                         ifq = &ip6intrq;
 354                         isr = NETISR_IPV6;
 355                         break;
 356 #endif
 357 #ifdef IPX
 358                 case AF_IPX:
 359                         ifq = &ipxintrq;
 360                         isr = NETISR_IPX;
 361                         break;
 362 #endif
 363 #ifdef ISO
 364                 case AF_ISO:
 365                         ifq = &clnlintrq;
 366                         isr = NETISR_ISO;
 367                         break;
 368 #endif
 369 #ifdef NETATALK
 370                 case AF_APPLETALK:
 371                         ifq = &atintrq2;
 372                         isr = NETISR_ATALK;
 373                         break;
 374 #endif
 375                 default:
 376                         printf("%s: can't handle af%d\n", ifp->if_xname, af);
 377                         m_freem(m);
 378                         return;
 379                 }
 380
 381                 s = splnet();
 382                 if (IF_QFULL(ifq)) {
 383                         IF_DROP(ifq);
 384                         splx(s);
 385                         m_freem(m);
 386                         return;
 387                 }
 388                 IF_ENQUEUE(ifq, m);
 389                 schednetisr(isr);
 390                 ifp->if_ipackets++;
 391                 ifp->if_ibytes += m->m_pkthdr.len;
 392                 splx(s);
 393         }
 394 }
 395 #endif /* ALTQ */
 396
 397 /* ARGSUSED */
 398 void
 399 lortrequest(int cmd, struct rtentry *rt,
 400     const struct rt_addrinfo *info)
 401 {
 402
 403         if (rt)
 404                 rt->rt_rmx.rmx_mtu = lo0ifp->if_mtu;
 405 }
 406
 407 /*
 408  * Process an ioctl request.
 409  */
 410 /* ARGSUSED */
 411 int
 412 loioctl(struct ifnet *ifp, u_long cmd, void *data)
 413 {
 414         struct ifaddr *ifa;
 415         struct ifreq *ifr = data;
 416         int error = 0;
 417
 418         switch (cmd) {
 419
 420         case SIOCINITIFADDR:
 421                 ifp->if_flags |= IFF_UP;
 422                 ifa = (struct ifaddr *)data;
 423                 if (ifa != NULL /*&& ifa->ifa_addr->sa_family == AF_ISO*/)
 424                         ifa->ifa_rtrequest = lortrequest;
 425                 /*
 426                  * Everything else is done at a higher level.
 427                  */
 428                 break;
 429
 430         case SIOCSIFMTU:
 431                 if ((unsigned)ifr->ifr_mtu > LOMTU_MAX)
 432                         error = EINVAL;
 433                 else if ((error = ifioctl_common(ifp, cmd, data)) == ENETRESET){
 434                         /* XXX update rt mtu for AF_ISO? */
 435                         error = 0;
 436                 }
 437                 break;
 438
 439         case SIOCADDMULTI:
 440         case SIOCDELMULTI:
 441                 if (ifr == NULL) {
 442                         error = EAFNOSUPPORT;           /* XXX */
 443                         break;
 444                 }
 445                 switch (ifreq_getaddr(cmd, ifr)->sa_family) {
 446
 447 #ifdef INET
 448                 case AF_INET:
 449                         break;
 450 #endif
 451 #ifdef INET6
 452                 case AF_INET6:
 453                         break;
 454 #endif
 455
 456                 default:
 457                         error = EAFNOSUPPORT;
 458                         break;
 459                 }
 460                 break;
 461
 462         default:
 463                 error = ifioctl_common(ifp, cmd, data);
 464         }
 465         return (error);
 466 }