sys/netproto/ipx/ipx_ip.c

   1 /*
   2  * Copyright (c) 1995, Mike Mitchell
   3  * Copyright (c) 1984, 1985, 1986, 1987, 1993
   4  *      The Regents of the University of California.  All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  * 3. All advertising materials mentioning features or use of this software
  15  *    must display the following acknowledgement:
  16  *      This product includes software developed by the University of
  17  *      California, Berkeley and its contributors.
  18  * 4. Neither the name of the University nor the names of its contributors
  19  *    may be used to endorse or promote products derived from this software
  20  *    without specific prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  *
  34  *      @(#)ipx_ip.c
  35  *
  36  * $FreeBSD: src/sys/netipx/ipx_ip.c,v 1.24.2.2 2003/01/23 21:06:48 sam Exp $
  37  * $DragonFly: src/sys/netproto/ipx/ipx_ip.c,v 1.16 2006/01/14 13:36:40 swildner Exp $
  38  */
  39
  40 /*
  41  * Software interface driver for encapsulating IPX in IP.
  42  */
  43
  44 #include "opt_inet.h"
  45 #include "opt_ipx.h"
  46
  47 #ifdef IPXIP
  48 #ifndef INET
  49 #error The option IPXIP requires option INET.
  50 #endif
  51
  52 #include <sys/param.h>
  53 #include <sys/systm.h>
  54 #include <sys/malloc.h>
  55 #include <sys/mbuf.h>
  56 #include <sys/protosw.h>
  57 #include <sys/socket.h>
  58 #include <sys/socketvar.h>
  59 #include <sys/sockio.h>
  60
  61 #include <net/if.h>
  62 #include <net/netisr.h>
  63 #include <net/route.h>
  64
  65 #include <netinet/in.h>
  66 #include <netinet/in_systm.h>
  67 #include <netinet/in_var.h>
  68 #include <netinet/ip.h>
  69 #include <netinet/ip_var.h>
  70
  71 #include "ipx.h"
  72 #include "ipx_if.h"
  73 #include "ipx_ip.h"
  74 #include "ipx_var.h"
  75
  76 static struct   ifnet ipxipif;
  77 static int      ipxipif_units;
  78
  79 /* list of all hosts and gateways or broadcast addrs */
  80 static struct   ifnet_en *ipxip_list;
  81
  82 static  struct ifnet_en *ipxipattach(void);
  83 static  int ipxip_free(struct ifnet *ifp);
  84 static  int ipxipioctl(struct ifnet *ifp, u_long cmd, caddr_t data,
  85                        struct ucred *cr);
  86 static  int ipxipoutput(struct ifnet *ifp, struct mbuf *m,
  87                         struct sockaddr *dst, struct rtentry *rt);
  88 static  void ipxip_rtchange(struct in_addr *dst);
  89 static  void ipxipstart(struct ifnet *ifp);
  90
  91 static struct ifnet_en *
  92 ipxipattach(void)
  93 {
  94         struct ifnet_en *m;
  95         struct ifnet *ifp;
  96
  97         if (ipxipif.if_mtu == 0) {
  98                 ifp = &ipxipif;
  99                 if_initname(ifp, "ipxip", ipxipif_units);
 100                 ifp->if_mtu = LOMTU;
 101                 ifp->if_ioctl = ipxipioctl;
 102                 ifp->if_output = ipxipoutput;
 103                 ifp->if_start = ipxipstart;
 104                 ifp->if_flags = IFF_POINTOPOINT;
 105         }
 106
 107         MALLOC((m), struct ifnet_en *, sizeof(*m), M_PCB, M_WAITOK | M_ZERO);
 108         m->ifen_next = ipxip_list;
 109         ipxip_list = m;
 110         ifp = &m->ifen_ifnet;
 111
 112         if_initname(ifp, "ipxip", ipxipif_units++);
 113         ifp->if_mtu = LOMTU;
 114         ifp->if_ioctl = ipxipioctl;
 115         ifp->if_output = ipxipoutput;
 116         ifp->if_start = ipxipstart;
 117         ifp->if_flags = IFF_POINTOPOINT;
 118         if_attach(ifp, NULL);
 119
 120         return (m);
 121 }
 122
 123
 124 /*
 125  * Process an ioctl request.
 126  */
 127 static int
 128 ipxipioctl(struct ifnet *ifp, u_long cmd, caddr_t data, struct ucred *cr)
 129 {
 130         int error = 0;
 131         struct ifreq *ifr;
 132
 133         switch (cmd) {
 134
 135         case SIOCSIFADDR:
 136                 ifp->if_flags |= IFF_UP;
 137                 /* fall into: */
 138
 139         case SIOCSIFDSTADDR:
 140                 /*
 141                  * Everything else is done at a higher level.
 142                  */
 143                 break;
 144
 145         case SIOCSIFFLAGS:
 146                 ifr = (struct ifreq *)data;
 147                 if ((ifr->ifr_flags & IFF_UP) == 0)
 148                         error = ipxip_free(ifp);
 149
 150
 151         default:
 152                 error = EINVAL;
 153         }
 154         return (error);
 155 }
 156
 157 static struct mbuf *ipxip_badlen;
 158 static struct mbuf *ipxip_lastin;
 159 static int ipxip_hold_input;
 160
 161 void
 162 ipxip_input(struct mbuf *m, ...)
 163 {
 164         struct ip *ip;
 165         struct ipx *ipx;
 166         int len, s;
 167
 168         if (ipxip_hold_input) {
 169                 if (ipxip_lastin != NULL) {
 170                         m_freem(ipxip_lastin);
 171                 }
 172                 ipxip_lastin = m_copym(m, 0, (int)M_COPYALL, MB_DONTWAIT);
 173         }
 174         /*
 175          * Get IP and IPX header together in first mbuf.
 176          */
 177         ipxipif.if_ipackets++;
 178         s = sizeof(struct ip) + sizeof(struct ipx);
 179         if (((m->m_flags & M_EXT) || m->m_len < s) &&
 180             (m = m_pullup(m, s)) == NULL) {
 181                 ipxipif.if_ierrors++;
 182                 return;
 183         }
 184         ip = mtod(m, struct ip *);
 185         if (ip->ip_hl > (sizeof(struct ip) >> 2)) {
 186                 ip_stripoptions(m);
 187                 if (m->m_len < s) {
 188                         if ((m = m_pullup(m, s)) == NULL) {
 189                                 ipxipif.if_ierrors++;
 190                                 return;
 191                         }
 192                         ip = mtod(m, struct ip *);
 193                 }
 194         }
 195
 196         /*
 197          * Make mbuf data length reflect IPX length.
 198          * If not enough data to reflect IPX length, drop.
 199          */
 200         m->m_data += sizeof(struct ip);
 201         m->m_len -= sizeof(struct ip);
 202         m->m_pkthdr.len -= sizeof(struct ip);
 203         ipx = mtod(m, struct ipx *);
 204         len = ntohs(ipx->ipx_len);
 205         if (len & 1)
 206                 len++;          /* Preserve Garbage Byte */
 207         if (ip->ip_len != len) {
 208                 if (len > ip->ip_len) {
 209                         ipxipif.if_ierrors++;
 210                         if (ipxip_badlen)
 211                                 m_freem(ipxip_badlen);
 212                         ipxip_badlen = m;
 213                         return;
 214                 }
 215                 /* Any extra will be trimmed off by the IPX routines */
 216         }
 217
 218         /*
 219          * Deliver to IPX
 220          */
 221         netisr_dispatch(NETISR_IPX, m);
 222 }
 223
 224 static int
 225 ipxipoutput(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
 226             struct rtentry *rt)
 227 {
 228         struct ifnet_en *ifn = (struct ifnet_en *)ifp;
 229         struct ip *ip;
 230         struct route *ro = &(ifn->ifen_route);
 231         int len = 0;
 232         struct ipx *ipx = mtod(m, struct ipx *);
 233         int error;
 234
 235         ifn->ifen_ifnet.if_opackets++;
 236         ipxipif.if_opackets++;
 237
 238         /*
 239          * Calculate data length and make space
 240          * for IP header.
 241          */
 242         len =  ntohs(ipx->ipx_len);
 243         if (len & 1)
 244                 len++;          /* Preserve Garbage Byte */
 245         /* following clause not necessary on vax */
 246         if (3 & (int)m->m_data) {
 247                 /* force longword alignment of ip hdr */
 248                 struct mbuf *m0 = m_gethdr(MT_HEADER, MB_DONTWAIT);
 249                 if (m0 == NULL) {
 250                         m_freem(m);
 251                         return (ENOBUFS);
 252                 }
 253                 MH_ALIGN(m0, sizeof(struct ip));
 254                 m0->m_flags = m->m_flags & M_COPYFLAGS;
 255                 m0->m_next = m;
 256                 m0->m_len = sizeof(struct ip);
 257                 m0->m_pkthdr.len = m0->m_len + m->m_len;
 258                 m = m0;
 259         } else {
 260                 M_PREPEND(m, sizeof(struct ip), MB_DONTWAIT);
 261                 if (m == NULL)
 262                         return (ENOBUFS);
 263         }
 264         /*
 265          * Fill in IP header.
 266          */
 267         ip = mtod(m, struct ip *);
 268         *(long *)ip = 0;
 269         ip->ip_p = IPPROTO_IDP;
 270         ip->ip_src = ifn->ifen_src;
 271         ip->ip_dst = ifn->ifen_dst;
 272         ip->ip_len = (u_short)len + sizeof(struct ip);
 273         ip->ip_ttl = MAXTTL;
 274
 275         /*
 276          * Output final datagram.
 277          */
 278         error =  (ip_output(m, (struct mbuf *)NULL, ro, SO_BROADCAST, NULL, NULL));
 279         if (error) {
 280                 ifn->ifen_ifnet.if_oerrors++;
 281                 ifn->ifen_ifnet.if_ierrors = error;
 282         }
 283         return (error);
 284         m_freem(m);
 285         return (ENETUNREACH);
 286 }
 287
 288 static void
 289 ipxipstart(struct ifnet *ifp)
 290 {
 291         panic("ipxip_start called\n");
 292 }
 293
 294 static struct ifreq ifr_ipxip = {"ipxip0"};
 295
 296 int
 297 ipxip_route(struct socket *so, struct sockopt *sopt)
 298 {
 299         int error;
 300         struct ifnet_en *ifn;
 301         struct sockaddr_in *src;
 302         struct ipxip_req rq;
 303         struct sockaddr_ipx *ipx_dst;
 304         struct sockaddr_in *ip_dst;
 305         struct route ro;
 306
 307         error = sooptcopyin(sopt, &rq, sizeof rq, sizeof rq);
 308         if (error)
 309                 return (error);
 310         ipx_dst = (struct sockaddr_ipx *)&rq.rq_ipx;
 311         ip_dst = (struct sockaddr_in *)&rq.rq_ip;
 312
 313         /*
 314          * First, make sure we already have an IPX address:
 315          */
 316         if (ipx_ifaddr == NULL)
 317                 return (EADDRNOTAVAIL);
 318         /*
 319          * Now, determine if we can get to the destination
 320          */
 321         bzero((caddr_t)&ro, sizeof(ro));
 322         ro.ro_dst = *(struct sockaddr *)ip_dst;
 323         rtalloc(&ro);
 324         if (ro.ro_rt == NULL || ro.ro_rt->rt_ifp == NULL) {
 325                 return (ENETUNREACH);
 326         }
 327
 328         /*
 329          * And see how he's going to get back to us:
 330          * i.e., what return ip address do we use?
 331          */
 332         {
 333                 struct in_ifaddr *ia;
 334                 struct ifnet *ifp = ro.ro_rt->rt_ifp;
 335
 336                 for (ia = TAILQ_FIRST(&in_ifaddrhead); ia != NULL;
 337                      ia = TAILQ_NEXT(ia, ia_link))
 338                         if (ia->ia_ifp == ifp)
 339                                 break;
 340                 if (ia == NULL)
 341                         ia = TAILQ_FIRST(&in_ifaddrhead);
 342                 if (ia == NULL) {
 343                         RTFREE(ro.ro_rt);
 344                         return (EADDRNOTAVAIL);
 345                 }
 346                 src = (struct sockaddr_in *)&ia->ia_addr;
 347         }
 348
 349         /*
 350          * Is there a free (pseudo-)interface or space?
 351          */
 352         for (ifn = ipxip_list; ifn != NULL; ifn = ifn->ifen_next) {
 353                 if ((ifn->ifen_ifnet.if_flags & IFF_UP) == 0)
 354                         break;
 355         }
 356         if (ifn == NULL)
 357                 ifn = ipxipattach();
 358         if (ifn == NULL) {
 359                 RTFREE(ro.ro_rt);
 360                 return (ENOBUFS);
 361         }
 362         ifn->ifen_route = ro;
 363         ifn->ifen_dst =  ip_dst->sin_addr;
 364         ifn->ifen_src = src->sin_addr;
 365
 366         /*
 367          * now configure this as a point to point link
 368          */
 369         ifr_ipxip.ifr_name[4] = '0' + ipxipif_units - 1;
 370         ifr_ipxip.ifr_dstaddr = *(struct sockaddr *)ipx_dst;
 371         ipx_control(so, (int)SIOCSIFDSTADDR, (caddr_t)&ifr_ipxip,
 372                         (struct ifnet *)ifn, sopt->sopt_td);
 373
 374         /* use any of our addresses */
 375         satoipx_addr(ifr_ipxip.ifr_addr).x_host =
 376                         ipx_ifaddr->ia_addr.sipx_addr.x_host;
 377
 378         return (ipx_control(so, (int)SIOCSIFADDR, (caddr_t)&ifr_ipxip,
 379                         (struct ifnet *)ifn, sopt->sopt_td));
 380 }
 381
 382 static int
 383 ipxip_free(struct ifnet *ifp)
 384 {
 385         struct ifnet_en *ifn = (struct ifnet_en *)ifp;
 386         struct route *ro = & ifn->ifen_route;
 387
 388         if (ro->ro_rt != NULL) {
 389                 RTFREE(ro->ro_rt);
 390                 ro->ro_rt = NULL;
 391         }
 392         ifp->if_flags &= ~IFF_UP;
 393         return (0);
 394 }
 395
 396 void
 397 ipxip_ctlinput(int cmd, struct sockaddr *sa, void *dummy)
 398 {
 399         struct sockaddr_in *sin;
 400
 401         if ((unsigned)cmd >= PRC_NCMDS)
 402                 return;
 403         if (sa->sa_family != AF_INET && sa->sa_family != AF_IMPLINK)
 404                 return;
 405         sin = (struct sockaddr_in *)sa;
 406         if (sin->sin_addr.s_addr == INADDR_ANY)
 407                 return;
 408
 409         switch (cmd) {
 410
 411         case PRC_ROUTEDEAD:
 412         case PRC_REDIRECT_NET:
 413         case PRC_REDIRECT_HOST:
 414         case PRC_REDIRECT_TOSNET:
 415         case PRC_REDIRECT_TOSHOST:
 416                 ipxip_rtchange(&sin->sin_addr);
 417                 break;
 418         }
 419 }
 420
 421 static void
 422 ipxip_rtchange(struct in_addr *dst)
 423 {
 424         struct ifnet_en *ifn;
 425
 426         for (ifn = ipxip_list; ifn != NULL; ifn = ifn->ifen_next) {
 427                 if (ifn->ifen_dst.s_addr == dst->s_addr &&
 428                         ifn->ifen_route.ro_rt != NULL) {
 429                                 RTFREE(ifn->ifen_route.ro_rt);
 430                                 ifn->ifen_route.ro_rt = NULL;
 431                 }
 432         }
 433 }
 434 #endif /* IPXIP */