bsd/net/if_dummy.c

   1 /*
   2  * Copyright (c) 2000-2008 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28 /*
  29  * Copyright (c) 1982, 1986, 1993
  30  *      The Regents of the University of California.  All rights reserved.
  31  *
  32  * Redistribution and use in source and binary forms, with or without
  33  * modification, are permitted provided that the following conditions
  34  * are met:
  35  * 1. Redistributions of source code must retain the above copyright
  36  *    notice, this list of conditions and the following disclaimer.
  37  * 2. Redistributions in binary form must reproduce the above copyright
  38  *    notice, this list of conditions and the following disclaimer in the
  39  *    documentation and/or other materials provided with the distribution.
  40  * 3. All advertising materials mentioning features or use of this software
  41  *    must display the following acknowledgement:
  42  *      This product includes software developed by the University of
  43  *      California, Berkeley and its contributors.
  44  * 4. 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 /*
  61  * derived from
  62  *      @(#)if_loop.c   8.1 (Berkeley) 6/10/93
  63  * Id: if_loop.c,v 1.22 1996/06/19 16:24:10 wollman Exp
  64  */
  65
  66 /*
  67  * Loopback interface driver for protocol testing and timing.
  68  */
  69 #if BSD310
  70 #include "opt_inet.h"
  71 #endif
  72 #include "dummy.h"
  73 #if NDUMMY > 0
  74
  75 #include <sys/param.h>
  76 #include <sys/systm.h>
  77 #include <sys/kernel.h>
  78 #include <sys/mbuf.h>
  79 #include <sys/socket.h>
  80 #include <sys/sockio.h>
  81 #include <sys/errno.h>
  82 #include <sys/time.h>
  83
  84 #include <net/if.h>
  85 #include <net/if_types.h>
  86 #include <net/route.h>
  87 #include <net/bpf.h>
  88
  89 #if     INET
  90 #include <netinet/in.h>
  91 #include <netinet/in_systm.h>
  92 #include <netinet/in_var.h>
  93 #include <netinet/ip.h>
  94 #endif
  95
  96 #if INET6
  97 #if !INET
  98 #include <netinet/in.h>
  99 #endif
 100 #include <netinet6/in6_var.h>
 101 #include <netinet6/ip6.h>
 102 #endif
 103
 104 #if NETATALK
 105 #include <netinet/if_ether.h>
 106 #include <netatalk/at.h>
 107 #include <netatalk/at_var.h>
 108 #endif /* NETATALK */
 109
 110 #include "bpfilter.h"
 111
 112 static int dummyioctl(struct ifnet *, u_long, caddr_t);
 113 int dummyoutput(struct ifnet *, register struct mbuf *, struct sockaddr *,
 114         register struct rtentry *);
 115 static void dummyrtrequest(int, struct rtentry *, struct sockaddr *);
 116
 117 static void dummyattach(void *);
 118 PSEUDO_SET(dummyattach, if_dummy);
 119
 120 #if TINY_DUMMYMTU
 121 #define DUMMYMTU        (1024+512)
 122 #else
 123 #define DUMMYMTU        16384
 124 #endif
 125 #define HAVE_OLD_BPF 1
 126
 127 static struct   ifnet dummyif[NDUMMY];
 128
 129 /* ARGSUSED */
 130 static void
 131 dummyattach(dummy)
 132         void *dummy;
 133 {
 134         register struct ifnet *ifp;
 135         register int i = 0;
 136
 137         for (i = 0; i < NDUMMY; i++) {
 138                 ifp = &dummyif[i];
 139 #if defined(__NetBSD__) || defined(__OpenBSD__)
 140                 sprintf(ifp->if_xname, "dummy%d", i);
 141 #else
 142                 ifp->if_name = "dummy";
 143                 ifp->if_unit = i;
 144 #endif
 145 #ifndef __bsdi__
 146                 ifp->if_softc = NULL;
 147 #endif
 148                 ifp->if_mtu = DUMMYMTU;
 149                 /* Change to BROADCAST experimentaly to announce its prefix. */
 150                 ifp->if_flags = /* IFF_LOOPBACK */ IFF_BROADCAST | IFF_MULTICAST;
 151                 ifp->if_ioctl = dummyioctl;
 152                 ifp->if_output = dummyoutput;
 153                 ifp->if_type = IFT_DUMMY;
 154                 ifp->if_hdrlen = 0;
 155                 ifp->if_addrlen = 0;
 156                 if_attach(ifp);
 157 #if NBPFILTER > 0
 158 #ifdef HAVE_OLD_BPF
 159                 bpfattach(ifp, DLT_NULL, sizeof(u_int));
 160 #else
 161                 bpfattach(&ifp->if_bpf, ifp, DLT_NULL, sizeof(u_int));
 162 #endif
 163 #endif
 164         }
 165 }
 166
 167 int
 168 dummyoutput(ifp, m, dst, rt)
 169         struct ifnet *ifp;
 170         register struct mbuf *m;
 171         struct sockaddr *dst;
 172         register struct rtentry *rt;
 173 {
 174         if ((m->m_flags & M_PKTHDR) == 0)
 175                 panic("dummyoutput no HDR");
 176 #if NBPFILTER > 0
 177         /* BPF write needs to be handled specially */
 178         if (dst->sa_family == AF_UNSPEC) {
 179                 dst->sa_family = *(mtod(m, int *));
 180                 m->m_len -= sizeof(int);
 181                 m->m_pkthdr.len -= sizeof(int);
 182                 m->m_data += sizeof(int);
 183         }
 184
 185         if (ifp->if_bpf) {
 186                 /* We need to prepend the address family as a four byte field. */
 187                 u_int af = dst->sa_family;
 188
 189                 bpf_tap_out(ifp, 0, m, &af, sizeof(af));
 190         }
 191 #endif
 192         m->m_pkthdr.rcvif = ifp;
 193
 194         if (rt != NULL) {
 195                 u_int32_t rt_flags = rt->rt_flags;
 196                 if (rt_flags & (RTF_REJECT | RTF_BLACKHOLE)) {
 197                         m_freem(m);
 198                         return ((rt_flags & RTF_BLACKHOLE) ? 0 :
 199                             (rt_flags & RTF_HOST) ? EHOSTUNREACH : ENETUNREACH);
 200                 }
 201         }
 202         ifp->if_opackets++;
 203         ifp->if_obytes += m->m_pkthdr.len;
 204         proto_inject(dst->sa_family, m);
 205         ifp->if_ipackets++;
 206         ifp->if_ibytes += m->m_pkthdr.len;
 207         return (0);
 208 }
 209
 210 /* ARGSUSED */
 211 static void
 212 dummyrtrequest(cmd, rt, sa)
 213         int cmd;
 214         struct rtentry *rt;
 215         struct sockaddr *sa;
 216 {
 217         if (rt != NULL) {
 218                 RT_LOCK_ASSERT_HELD(rt);
 219                 rt->rt_rmx.rmx_mtu = rt->rt_ifp->if_mtu; /* for ISO */
 220                 /*
 221                  * For optimal performance, the send and receive buffers
 222                  * should be at least twice the MTU plus a little more for
 223                  * overhead.
 224                  */
 225                 rt->rt_rmx.rmx_recvpipe =
 226                         rt->rt_rmx.rmx_sendpipe = 3 * DUMMYMTU;
 227         }
 228 }
 229
 230 /*
 231  * Process an ioctl request.
 232  */
 233 /* ARGSUSED */
 234 static int
 235 dummyioctl(ifp, cmd, data)
 236         register struct ifnet *ifp;
 237         u_long cmd;
 238         caddr_t data;
 239 {
 240         register struct ifaddr *ifa;
 241         register struct ifreq *ifr = (struct ifreq *)data;
 242         register int error = 0;
 243
 244         switch (cmd) {
 245
 246         case SIOCSIFADDR:
 247                 ifnet_set_flags(ifp, IFF_UP | IFF_RUNNING, IFF_UP | IFF_RUNNING);
 248                 ifa = (struct ifaddr *)data;
 249                 ifa->ifa_rtrequest = dummyrtrequest;
 250                 /*
 251                  * Everything else is done at a higher level.
 252                  */
 253                 break;
 254
 255         case SIOCADDMULTI:
 256         case SIOCDELMULTI:
 257                 if (ifr == 0) {
 258                         error = EAFNOSUPPORT;           /* XXX */
 259                         break;
 260                 }
 261                 switch (ifr->ifr_addr.sa_family) {
 262
 263 #if INET
 264                 case AF_INET:
 265                         break;
 266 #endif
 267 #if INET6
 268                 case AF_INET6:
 269                         break;
 270 #endif
 271
 272                 default:
 273                         error = EAFNOSUPPORT;
 274                         break;
 275                 }
 276                 break;
 277
 278         case SIOCSIFMTU:
 279                 ifp->if_mtu = ifr->ifr_mtu;
 280                 break;
 281
 282         case SIOCSIFFLAGS:
 283                 break;
 284
 285         default:
 286                 error = EINVAL;
 287         }
 288         return (error);
 289 }
 290 #endif /* NDUMMY > 0 */