bsd/net/if_dummy.c

   1 /*
   2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_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. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23 /*
  24  * Copyright (c) 1982, 1986, 1993
  25  *      The Regents of the University of California.  All rights reserved.
  26  *
  27  * Redistribution and use in source and binary forms, with or without
  28  * modification, are permitted provided that the following conditions
  29  * are met:
  30  * 1. Redistributions of source code must retain the above copyright
  31  *    notice, this list of conditions and the following disclaimer.
  32  * 2. Redistributions in binary form must reproduce the above copyright
  33  *    notice, this list of conditions and the following disclaimer in the
  34  *    documentation and/or other materials provided with the distribution.
  35  * 3. All advertising materials mentioning features or use of this software
  36  *    must display the following acknowledgement:
  37  *      This product includes software developed by the University of
  38  *      California, Berkeley and its contributors.
  39  * 4. Neither the name of the University nor the names of its contributors
  40  *    may be used to endorse or promote products derived from this software
  41  *    without specific prior written permission.
  42  *
  43  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  44  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  45  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  46  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  47  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  48  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  49  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  50  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  51  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  52  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  53  * SUCH DAMAGE.
  54  */
  55 /*
  56  * derived from
  57  *      @(#)if_loop.c   8.1 (Berkeley) 6/10/93
  58  * Id: if_loop.c,v 1.22 1996/06/19 16:24:10 wollman Exp
  59  */
  60
  61 /*
  62  * Loopback interface driver for protocol testing and timing.
  63  */
  64 #if BSD310
  65 #include "opt_inet.h"
  66 #endif
  67 #include "dummy.h"
  68 #if NDUMMY > 0
  69
  70 #include <sys/param.h>
  71 #include <sys/systm.h>
  72 #include <sys/kernel.h>
  73 #include <sys/mbuf.h>
  74 #include <sys/socket.h>
  75 #include <sys/sockio.h>
  76 #include <sys/errno.h>
  77 #include <sys/time.h>
  78
  79 #include <net/if.h>
  80 #include <net/if_types.h>
  81 #include <net/route.h>
  82 #include <net/bpf.h>
  83
  84 #if     INET
  85 #include <netinet/in.h>
  86 #include <netinet/in_systm.h>
  87 #include <netinet/in_var.h>
  88 #include <netinet/ip.h>
  89 #endif
  90
  91 #if IPX
  92 #include <netipx/ipx.h>
  93 #include <netipx/ipx_if.h>
  94 #endif
  95
  96 #if INET6
  97 #ifndef 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
 175         if ((m->m_flags & M_PKTHDR) == 0)
 176                 panic("dummyoutput no HDR");
 177 #if NBPFILTER > 0
 178         /* BPF write needs to be handled specially */
 179         if (dst->sa_family == AF_UNSPEC) {
 180                 dst->sa_family = *(mtod(m, int *));
 181                 m->m_len -= sizeof(int);
 182                 m->m_pkthdr.len -= sizeof(int);
 183                 m->m_data += sizeof(int);
 184         }
 185
 186         if (ifp->if_bpf) {
 187                 /*
 188                  * We need to prepend the address family as
 189                  * a four byte field.  Cons up a dummy header
 190                  * to pacify bpf.  This is safe because bpf
 191                  * will only read from the mbuf (i.e., it won't
 192                  * try to free it or keep a pointer a to it).
 193                  */
 194                 struct mbuf m0;
 195                 u_int af = dst->sa_family;
 196
 197                 m0.m_next = m;
 198                 m0.m_len = 4;
 199                 m0.m_data = (char *)&af;
 200
 201 #ifdef HAVE_OLD_BPF
 202                 bpf_mtap(ifp, &m0);
 203 #else
 204                 bpf_mtap(ifp->if_bpf, &m0);
 205 #endif
 206         }
 207 #endif
 208         m->m_pkthdr.rcvif = ifp;
 209
 210         if (rt && rt->rt_flags & (RTF_REJECT|RTF_BLACKHOLE)) {
 211                 m_freem(m);
 212                 return (rt->rt_flags & RTF_BLACKHOLE ? 0 :
 213                         rt->rt_flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH);
 214         }
 215         ifp->if_opackets++;
 216         ifp->if_obytes += m->m_pkthdr.len;
 217         proto_inject(dst->sa_family, m);
 218         ifp->if_ipackets++;
 219         ifp->if_ibytes += m->m_pkthdr.len;
 220         return (0);
 221 }
 222
 223 /* ARGSUSED */
 224 static void
 225 dummyrtrequest(cmd, rt, sa)
 226         int cmd;
 227         struct rtentry *rt;
 228         struct sockaddr *sa;
 229 {
 230         if (rt) {
 231                 rt->rt_rmx.rmx_mtu = rt->rt_ifp->if_mtu; /* for ISO */
 232                 /*
 233                  * For optimal performance, the send and receive buffers
 234                  * should be at least twice the MTU plus a little more for
 235                  * overhead.
 236                  */
 237                 rt->rt_rmx.rmx_recvpipe =
 238                         rt->rt_rmx.rmx_sendpipe = 3 * DUMMYMTU;
 239         }
 240 }
 241
 242 /*
 243  * Process an ioctl request.
 244  */
 245 /* ARGSUSED */
 246 static int
 247 dummyioctl(ifp, cmd, data)
 248         register struct ifnet *ifp;
 249         u_long cmd;
 250         caddr_t data;
 251 {
 252         register struct ifaddr *ifa;
 253         register struct ifreq *ifr = (struct ifreq *)data;
 254         register int error = 0;
 255
 256         switch (cmd) {
 257
 258         case SIOCSIFADDR:
 259                 ifnet_set_flags(ifp, IFF_UP | IFF_RUNNING, IFF_UP | IFF_RUNNING);
 260                 ifa = (struct ifaddr *)data;
 261                 ifa->ifa_rtrequest = dummyrtrequest;
 262                 /*
 263                  * Everything else is done at a higher level.
 264                  */
 265                 break;
 266
 267         case SIOCADDMULTI:
 268         case SIOCDELMULTI:
 269                 if (ifr == 0) {
 270                         error = EAFNOSUPPORT;           /* XXX */
 271                         break;
 272                 }
 273                 switch (ifr->ifr_addr.sa_family) {
 274
 275 #if INET
 276                 case AF_INET:
 277                         break;
 278 #endif
 279 #if INET6
 280                 case AF_INET6:
 281                         break;
 282 #endif
 283
 284                 default:
 285                         error = EAFNOSUPPORT;
 286                         break;
 287                 }
 288                 break;
 289
 290         case SIOCSIFMTU:
 291                 ifp->if_mtu = ifr->ifr_mtu;
 292                 break;
 293
 294         case SIOCSIFFLAGS:
 295                 break;
 296
 297         default:
 298                 error = EINVAL;
 299         }
 300         return (error);
 301 }
 302 #endif /* NDUMMY > 0 */