sys/net/if_faith.c

   1 /*      $NetBSD: if_faith.c,v 1.44 2008/10/24 17:07:33 dyoung Exp $     */
   2 /*      $KAME: if_faith.c,v 1.21 2001/02/20 07:59:26 itojun Exp $       */
   3
   4 /*
   5  * Copyright (c) 1982, 1986, 1993
   6  *      The Regents of the University of California.  All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  * 3. Neither the name of the University nor the names of its contributors
  17  *    may be used to endorse or promote products derived from this software
  18  *    without specific prior written permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  30  * SUCH DAMAGE.
  31  */
  32 /*
  33  * derived from
  34  *      @(#)if_loop.c   8.1 (Berkeley) 6/10/93
  35  * Id: if_loop.c,v 1.22 1996/06/19 16:24:10 wollman Exp
  36  */
  37
  38 /*
  39  * IPv6-to-IPv4 TCP relay capturing interface
  40  */
  41
  42 #include <sys/cdefs.h>
  43 __KERNEL_RCSID(0, "$NetBSD: if_faith.c,v 1.44 2008/10/24 17:07:33 dyoung Exp $");
  44
  45 #include "opt_inet.h"
  46
  47 #include <sys/param.h>
  48 #include <sys/systm.h>
  49 #include <sys/kernel.h>
  50 #include <sys/mbuf.h>
  51 #include <sys/socket.h>
  52 #include <sys/errno.h>
  53 #include <sys/ioctl.h>
  54 #include <sys/time.h>
  55 #include <sys/queue.h>
  56
  57 #include <sys/cpu.h>
  58
  59 #include <net/if.h>
  60 #include <net/if_types.h>
  61 #include <net/netisr.h>
  62 #include <net/route.h>
  63 #include <net/bpf.h>
  64 #include <net/if_faith.h>
  65
  66 #ifdef  INET
  67 #include <netinet/in.h>
  68 #include <netinet/in_systm.h>
  69 #include <netinet/in_var.h>
  70 #include <netinet/ip.h>
  71 #endif
  72
  73 #ifdef INET6
  74 #ifndef INET
  75 #include <netinet/in.h>
  76 #endif
  77 #include <netinet6/in6_var.h>
  78 #include <netinet/ip6.h>
  79 #include <netinet6/ip6_var.h>
  80 #endif
  81
  82 #include "bpfilter.h"
  83
  84 #include <net/net_osdep.h>
  85
  86 static int      faithioctl(struct ifnet *, u_long, void *);
  87 static int      faithoutput(struct ifnet *, struct mbuf *,
  88                             const struct sockaddr *, struct rtentry *);
  89 static void     faithrtrequest(int, struct rtentry *,
  90                                const struct rt_addrinfo *);
  91
  92 void    faithattach(int);
  93
  94 static int      faith_clone_create(struct if_clone *, int);
  95 static int      faith_clone_destroy(struct ifnet *);
  96
  97 static struct if_clone faith_cloner =
  98     IF_CLONE_INITIALIZER("faith", faith_clone_create, faith_clone_destroy);
  99
 100 #define FAITHMTU        1500
 101
 102 /* ARGSUSED */
 103 void
 104 faithattach(int count)
 105 {
 106
 107         if_clone_attach(&faith_cloner);
 108 }
 109
 110 static int
 111 faith_clone_create(struct if_clone *ifc, int unit)
 112 {
 113         struct ifnet *ifp;
 114
 115         ifp = if_alloc(IFT_FAITH);
 116
 117         if_initname(ifp, ifc->ifc_name, unit);
 118
 119         ifp->if_mtu = FAITHMTU;
 120         /* Change to BROADCAST experimentaly to announce its prefix. */
 121         ifp->if_flags = /* IFF_LOOPBACK */ IFF_BROADCAST | IFF_MULTICAST;
 122         ifp->if_ioctl = faithioctl;
 123         ifp->if_output = faithoutput;
 124         ifp->if_type = IFT_FAITH;
 125         ifp->if_hdrlen = 0;
 126         ifp->if_addrlen = 0;
 127         ifp->if_dlt = DLT_NULL;
 128         if_attach(ifp);
 129         if_alloc_sadl(ifp);
 130 #if NBPFILTER > 0
 131         bpfattach(ifp, DLT_NULL, sizeof(u_int));
 132 #endif
 133         return (0);
 134 }
 135
 136 int
 137 faith_clone_destroy(struct ifnet *ifp)
 138 {
 139
 140 #if NBPFILTER > 0
 141         bpfdetach(ifp);
 142 #endif
 143         if_detach(ifp);
 144         free(ifp, M_DEVBUF);
 145
 146         return (0);
 147 }
 148
 149 static int
 150 faithoutput(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst,
 151     struct rtentry *rt)
 152 {
 153         int s, isr;
 154         uint32_t af;
 155         struct ifqueue *ifq = 0;
 156
 157         if ((m->m_flags & M_PKTHDR) == 0)
 158                 panic("faithoutput no HDR");
 159         af = dst->sa_family;
 160 #if NBPFILTER > 0
 161         /* BPF write needs to be handled specially */
 162         if (af == AF_UNSPEC) {
 163                 af = *(mtod(m, int *));
 164                 m_adj(m, sizeof(int));
 165         }
 166
 167         if (ifp->if_bpf)
 168                 bpf_mtap_af(ifp->if_bpf, af, m);
 169 #endif
 170
 171         if (rt && rt->rt_flags & (RTF_REJECT|RTF_BLACKHOLE)) {
 172                 m_freem(m);
 173                 return (rt->rt_flags & RTF_BLACKHOLE ? 0 :
 174                         rt->rt_flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH);
 175         }
 176         ifp->if_opackets++;
 177         ifp->if_obytes += m->m_pkthdr.len;
 178         switch (af) {
 179 #ifdef INET
 180         case AF_INET:
 181                 ifq = &ipintrq;
 182                 isr = NETISR_IP;
 183                 break;
 184 #endif
 185 #ifdef INET6
 186         case AF_INET6:
 187                 ifq = &ip6intrq;
 188                 isr = NETISR_IPV6;
 189                 break;
 190 #endif
 191         default:
 192                 m_freem(m);
 193                 return EAFNOSUPPORT;
 194         }
 195
 196         /* XXX do we need more sanity checks? */
 197
 198         m->m_pkthdr.rcvif = ifp;
 199         s = splnet();
 200         if (IF_QFULL(ifq)) {
 201                 IF_DROP(ifq);
 202                 m_freem(m);
 203                 splx(s);
 204                 return (ENOBUFS);
 205         }
 206         IF_ENQUEUE(ifq, m);
 207         schednetisr(isr);
 208         ifp->if_ipackets++;
 209         ifp->if_ibytes += m->m_pkthdr.len;
 210         splx(s);
 211         return (0);
 212 }
 213
 214 /* ARGSUSED */
 215 static void
 216 faithrtrequest(int cmd, struct rtentry *rt,
 217     const struct rt_addrinfo *info)
 218 {
 219         if (rt)
 220                 rt->rt_rmx.rmx_mtu = rt->rt_ifp->if_mtu; /* for ISO */
 221 }
 222
 223 /*
 224  * Process an ioctl request.
 225  */
 226 /* ARGSUSED */
 227 static int
 228 faithioctl(struct ifnet *ifp, u_long cmd, void *data)
 229 {
 230         struct ifaddr *ifa;
 231         struct ifreq *ifr = (struct ifreq *)data;
 232         int error = 0;
 233
 234         switch (cmd) {
 235
 236         case SIOCINITIFADDR:
 237                 ifp->if_flags |= IFF_UP | IFF_RUNNING;
 238                 ifa = (struct ifaddr *)data;
 239                 ifa->ifa_rtrequest = faithrtrequest;
 240                 /*
 241                  * Everything else is done at a higher level.
 242                  */
 243                 break;
 244
 245         case SIOCADDMULTI:
 246         case SIOCDELMULTI:
 247                 if (ifr == 0) {
 248                         error = EAFNOSUPPORT;           /* XXX */
 249                         break;
 250                 }
 251                 switch (ifr->ifr_addr.sa_family) {
 252 #ifdef INET
 253                 case AF_INET:
 254                         break;
 255 #endif
 256 #ifdef INET6
 257                 case AF_INET6:
 258                         break;
 259 #endif
 260
 261                 default:
 262                         error = EAFNOSUPPORT;
 263                         break;
 264                 }
 265                 break;
 266
 267         default:
 268                 if ((error = ifioctl_common(ifp, cmd, data)) == ENETRESET)
 269                         error = 0;
 270                 break;
 271         }
 272         return (error);
 273 }
 274
 275 #ifdef INET6
 276 /*
 277  * XXX could be slow
 278  * XXX could be layer violation to call sys/net from sys/netinet6
 279  */
 280 int
 281 faithprefix(struct in6_addr *in6)
 282 {
 283         struct rtentry *rt;
 284         struct sockaddr_in6 sin6;
 285         int ret;
 286
 287         if (ip6_keepfaith == 0)
 288                 return 0;
 289
 290         memset(&sin6, 0, sizeof(sin6));
 291         sin6.sin6_family = AF_INET6;
 292         sin6.sin6_len = sizeof(struct sockaddr_in6);
 293         sin6.sin6_addr = *in6;
 294         rt = rtalloc1((struct sockaddr *)&sin6, 0);
 295         if (rt && rt->rt_ifp && rt->rt_ifp->if_type == IFT_FAITH &&
 296             (rt->rt_ifp->if_flags & IFF_UP) != 0)
 297                 ret = 1;
 298         else
 299                 ret = 0;
 300         if (rt)
 301                 RTFREE(rt);
 302         return ret;
 303 }
 304 #endif