[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]

FreeBSD/Linux Kernel Cross Reference
sys/net/if_gre.c

Version: -  FREEBSD  -  FREEBSD10  -  FREEBSD9  -  FREEBSD92  -  FREEBSD91  -  FREEBSD90  -  FREEBSD8  -  FREEBSD82  -  FREEBSD81  -  FREEBSD80  -  FREEBSD7  -  FREEBSD74  -  FREEBSD73  -  FREEBSD72  -  FREEBSD71  -  FREEBSD70  -  FREEBSD6  -  FREEBSD64  -  FREEBSD63  -  FREEBSD62  -  FREEBSD61  -  FREEBSD60  -  FREEBSD5  -  FREEBSD55  -  FREEBSD54  -  FREEBSD53  -  FREEBSD52  -  FREEBSD51  -  FREEBSD50  -  FREEBSD4  -  FREEBSD3  -  FREEBSD22  -  cheribsd  -  linux-2.6  -  linux-2.4.22  -  MK83  -  MK84  -  PLAN9  -  DFBSD  -  NETBSD  -  NETBSD5  -  NETBSD4  -  NETBSD3  -  NETBSD20  -  OPENBSD  -  xnu-517  -  xnu-792  -  xnu-792.6.70  -  xnu-1228  -  xnu-1456.1.26  -  xnu-1699.24.8  -  xnu-2050.18.24  -  OPENSOLARIS  -  minix-3-1-1  -  FREEBSD-LIBC  -  FREEBSD8-LIBC  -  FREEBSD7-LIBC  -  FREEBSD6-LIBC  -  GLIBC27 
SearchContext: -  none  -  3  -  10 

    1 /*      $NetBSD: if_gre.c,v 1.49 2003/12/11 00:22:29 itojun Exp $ */
    2 /*       $FreeBSD: releng/8.1/sys/net/if_gre.c 196019 2009-08-01 19:26:27Z rwatson $ */
    3 
    4 /*-
    5  * Copyright (c) 1998 The NetBSD Foundation, Inc.
    6  * All rights reserved.
    7  *
    8  * This code is derived from software contributed to The NetBSD Foundation
    9  * by Heiko W.Rupp <hwr@pilhuhn.de>
   10  *
   11  * IPv6-over-GRE contributed by Gert Doering <gert@greenie.muc.de>
   12  *
   13  * Redistribution and use in source and binary forms, with or without
   14  * modification, are permitted provided that the following conditions
   15  * are met:
   16  * 1. Redistributions of source code must retain the above copyright
   17  *    notice, this list of conditions and the following disclaimer.
   18  * 2. Redistributions in binary form must reproduce the above copyright
   19  *    notice, this list of conditions and the following disclaimer in the
   20  *    documentation and/or other materials provided with the distribution.
   21  * 3. All advertising materials mentioning features or use of this software
   22  *    must display the following acknowledgement:
   23  *        This product includes software developed by the NetBSD
   24  *        Foundation, Inc. and its contributors.
   25  * 4. Neither the name of The NetBSD Foundation nor the names of its
   26  *    contributors may be used to endorse or promote products derived
   27  *    from this software without specific prior written permission.
   28  *
   29  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
   30  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
   31  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
   32  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
   33  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
   34  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
   35  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
   36  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
   37  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
   38  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
   39  * POSSIBILITY OF SUCH DAMAGE.
   40  */
   41 
   42 /*
   43  * Encapsulate L3 protocols into IP
   44  * See RFC 2784 (successor of RFC 1701 and 1702) for more details.
   45  * If_gre is compatible with Cisco GRE tunnels, so you can
   46  * have a NetBSD box as the other end of a tunnel interface of a Cisco
   47  * router. See gre(4) for more details.
   48  * Also supported:  IP in IP encaps (proto 55) as of RFC 2004
   49  */
   50 
   51 #include "opt_atalk.h"
   52 #include "opt_inet.h"
   53 #include "opt_inet6.h"
   54 
   55 #include <sys/param.h>
   56 #include <sys/kernel.h>
   57 #include <sys/malloc.h>
   58 #include <sys/module.h>
   59 #include <sys/mbuf.h>
   60 #include <sys/priv.h>
   61 #include <sys/proc.h>
   62 #include <sys/protosw.h>
   63 #include <sys/socket.h>
   64 #include <sys/sockio.h>
   65 #include <sys/sysctl.h>
   66 #include <sys/systm.h>
   67 
   68 #include <net/ethernet.h>
   69 #include <net/if.h>
   70 #include <net/if_clone.h>
   71 #include <net/if_types.h>
   72 #include <net/route.h>
   73 #include <net/vnet.h>
   74 
   75 #ifdef INET
   76 #include <netinet/in.h>
   77 #include <netinet/in_systm.h>
   78 #include <netinet/in_var.h>
   79 #include <netinet/ip.h>
   80 #include <netinet/ip_gre.h>
   81 #include <netinet/ip_var.h>
   82 #include <netinet/ip_encap.h>
   83 #else
   84 #error "Huh? if_gre without inet?"
   85 #endif
   86 
   87 #include <net/bpf.h>
   88 
   89 #include <net/if_gre.h>
   90 
   91 /*
   92  * It is not easy to calculate the right value for a GRE MTU.
   93  * We leave this task to the admin and use the same default that
   94  * other vendors use.
   95  */
   96 #define GREMTU  1476
   97 
   98 #define GRENAME "gre"
   99 
  100 /*
  101  * gre_mtx protects all global variables in if_gre.c.
  102  * XXX: gre_softc data not protected yet.
  103  */
  104 struct mtx gre_mtx;
  105 static MALLOC_DEFINE(M_GRE, GRENAME, "Generic Routing Encapsulation");
  106 
  107 struct gre_softc_head gre_softc_list;
  108 
  109 static int      gre_clone_create(struct if_clone *, int, caddr_t);
  110 static void     gre_clone_destroy(struct ifnet *);
  111 static int      gre_ioctl(struct ifnet *, u_long, caddr_t);
  112 static int      gre_output(struct ifnet *, struct mbuf *, struct sockaddr *,
  113                     struct route *ro);
  114 
  115 IFC_SIMPLE_DECLARE(gre, 0);
  116 
  117 static int gre_compute_route(struct gre_softc *sc);
  118 
  119 static void     greattach(void);
  120 
  121 #ifdef INET
  122 extern struct domain inetdomain;
  123 static const struct protosw in_gre_protosw = {
  124         .pr_type =              SOCK_RAW,
  125         .pr_domain =            &inetdomain,
  126         .pr_protocol =          IPPROTO_GRE,
  127         .pr_flags =             PR_ATOMIC|PR_ADDR,
  128         .pr_input =             gre_input,
  129         .pr_output =            (pr_output_t *)rip_output,
  130         .pr_ctlinput =          rip_ctlinput,
  131         .pr_ctloutput =         rip_ctloutput,
  132         .pr_usrreqs =           &rip_usrreqs
  133 };
  134 static const struct protosw in_mobile_protosw = {
  135         .pr_type =              SOCK_RAW,
  136         .pr_domain =            &inetdomain,
  137         .pr_protocol =          IPPROTO_MOBILE,
  138         .pr_flags =             PR_ATOMIC|PR_ADDR,
  139         .pr_input =             gre_mobile_input,
  140         .pr_output =            (pr_output_t *)rip_output,
  141         .pr_ctlinput =          rip_ctlinput,
  142         .pr_ctloutput =         rip_ctloutput,
  143         .pr_usrreqs =           &rip_usrreqs
  144 };
  145 #endif
  146 
  147 SYSCTL_DECL(_net_link);
  148 SYSCTL_NODE(_net_link, IFT_TUNNEL, gre, CTLFLAG_RW, 0,
  149     "Generic Routing Encapsulation");
  150 #ifndef MAX_GRE_NEST
  151 /*
  152  * This macro controls the default upper limitation on nesting of gre tunnels.
  153  * Since, setting a large value to this macro with a careless configuration
  154  * may introduce system crash, we don't allow any nestings by default.
  155  * If you need to configure nested gre tunnels, you can define this macro
  156  * in your kernel configuration file.  However, if you do so, please be
  157  * careful to configure the tunnels so that it won't make a loop.
  158  */
  159 #define MAX_GRE_NEST 1
  160 #endif
  161 static int max_gre_nesting = MAX_GRE_NEST;
  162 SYSCTL_INT(_net_link_gre, OID_AUTO, max_nesting, CTLFLAG_RW,
  163     &max_gre_nesting, 0, "Max nested tunnels");
  164 
  165 /* ARGSUSED */
  166 static void
  167 greattach(void)
  168 {
  169 
  170         mtx_init(&gre_mtx, "gre_mtx", NULL, MTX_DEF);
  171         LIST_INIT(&gre_softc_list);
  172         if_clone_attach(&gre_cloner);
  173 }
  174 
  175 static int
  176 gre_clone_create(ifc, unit, params)
  177         struct if_clone *ifc;
  178         int unit;
  179         caddr_t params;
  180 {
  181         struct gre_softc *sc;
  182 
  183         sc = malloc(sizeof(struct gre_softc), M_GRE, M_WAITOK | M_ZERO);
  184 
  185         GRE2IFP(sc) = if_alloc(IFT_TUNNEL);
  186         if (GRE2IFP(sc) == NULL) {
  187                 free(sc, M_GRE);
  188                 return (ENOSPC);
  189         }
  190 
  191         GRE2IFP(sc)->if_softc = sc;
  192         if_initname(GRE2IFP(sc), ifc->ifc_name, unit);
  193 
  194         GRE2IFP(sc)->if_snd.ifq_maxlen = IFQ_MAXLEN;
  195         GRE2IFP(sc)->if_addrlen = 0;
  196         GRE2IFP(sc)->if_hdrlen = 24; /* IP + GRE */
  197         GRE2IFP(sc)->if_mtu = GREMTU;
  198         GRE2IFP(sc)->if_flags = IFF_POINTOPOINT|IFF_MULTICAST;
  199         GRE2IFP(sc)->if_output = gre_output;
  200         GRE2IFP(sc)->if_ioctl = gre_ioctl;
  201         sc->g_dst.s_addr = sc->g_src.s_addr = INADDR_ANY;
  202         sc->g_proto = IPPROTO_GRE;
  203         GRE2IFP(sc)->if_flags |= IFF_LINK0;
  204         sc->encap = NULL;
  205         sc->called = 0;
  206         sc->gre_fibnum = curthread->td_proc->p_fibnum;
  207         sc->wccp_ver = WCCP_V1;
  208         sc->key = 0;
  209         if_attach(GRE2IFP(sc));
  210         bpfattach(GRE2IFP(sc), DLT_NULL, sizeof(u_int32_t));
  211         mtx_lock(&gre_mtx);
  212         LIST_INSERT_HEAD(&gre_softc_list, sc, sc_list);
  213         mtx_unlock(&gre_mtx);
  214         return (0);
  215 }
  216 
  217 static void
  218 gre_clone_destroy(ifp)
  219         struct ifnet *ifp;
  220 {
  221         struct gre_softc *sc = ifp->if_softc;
  222 
  223         mtx_lock(&gre_mtx);
  224         LIST_REMOVE(sc, sc_list);
  225         mtx_unlock(&gre_mtx);
  226 
  227 #ifdef INET
  228         if (sc->encap != NULL)
  229                 encap_detach(sc->encap);
  230 #endif
  231         bpfdetach(ifp);
  232         if_detach(ifp);
  233         if_free(ifp);
  234         free(sc, M_GRE);
  235 }
  236 
  237 /*
  238  * The output routine. Takes a packet and encapsulates it in the protocol
  239  * given by sc->g_proto. See also RFC 1701 and RFC 2004
  240  */
  241 static int
  242 gre_output(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
  243            struct route *ro)
  244 {
  245         int error = 0;
  246         struct gre_softc *sc = ifp->if_softc;
  247         struct greip *gh;
  248         struct ip *ip;
  249         u_short gre_ip_id = 0;
  250         uint8_t gre_ip_tos = 0;
  251         u_int16_t etype = 0;
  252         struct mobile_h mob_h;
  253         u_int32_t af;
  254         int extra = 0;
  255 
  256         /*
  257          * gre may cause infinite recursion calls when misconfigured.
  258          * We'll prevent this by introducing upper limit.
  259          */
  260         if (++(sc->called) > max_gre_nesting) {
  261                 printf("%s: gre_output: recursively called too many "
  262                        "times(%d)\n", if_name(GRE2IFP(sc)), sc->called);
  263                 m_freem(m);
  264                 error = EIO;    /* is there better errno? */
  265                 goto end;
  266         }
  267 
  268         if (!((ifp->if_flags & IFF_UP) &&
  269             (ifp->if_drv_flags & IFF_DRV_RUNNING)) ||
  270             sc->g_src.s_addr == INADDR_ANY || sc->g_dst.s_addr == INADDR_ANY) {
  271                 m_freem(m);
  272                 error = ENETDOWN;
  273                 goto end;
  274         }
  275 
  276         gh = NULL;
  277         ip = NULL;
  278 
  279         /* BPF writes need to be handled specially. */
  280         if (dst->sa_family == AF_UNSPEC) {
  281                 bcopy(dst->sa_data, &af, sizeof(af));
  282                 dst->sa_family = af;
  283         }
  284 
  285         if (bpf_peers_present(ifp->if_bpf)) {
  286                 af = dst->sa_family;
  287                 bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m);
  288         }
  289 
  290         m->m_flags &= ~(M_BCAST|M_MCAST);
  291 
  292         if (sc->g_proto == IPPROTO_MOBILE) {
  293                 if (dst->sa_family == AF_INET) {
  294                         struct mbuf *m0;
  295                         int msiz;
  296 
  297                         ip = mtod(m, struct ip *);
  298 
  299                         /*
  300                          * RFC2004 specifies that fragmented diagrams shouldn't
  301                          * be encapsulated.
  302                          */
  303                         if (ip->ip_off & (IP_MF | IP_OFFMASK)) {
  304                                 _IF_DROP(&ifp->if_snd);
  305                                 m_freem(m);
  306                                 error = EINVAL;    /* is there better errno? */
  307                                 goto end;
  308                         }
  309                         memset(&mob_h, 0, MOB_H_SIZ_L);
  310                         mob_h.proto = (ip->ip_p) << 8;
  311                         mob_h.odst = ip->ip_dst.s_addr;
  312                         ip->ip_dst.s_addr = sc->g_dst.s_addr;
  313 
  314                         /*
  315                          * If the packet comes from our host, we only change
  316                          * the destination address in the IP header.
  317                          * Else we also need to save and change the source
  318                          */
  319                         if (in_hosteq(ip->ip_src, sc->g_src)) {
  320                                 msiz = MOB_H_SIZ_S;
  321                         } else {
  322                                 mob_h.proto |= MOB_H_SBIT;
  323                                 mob_h.osrc = ip->ip_src.s_addr;
  324                                 ip->ip_src.s_addr = sc->g_src.s_addr;
  325                                 msiz = MOB_H_SIZ_L;
  326                         }
  327                         mob_h.proto = htons(mob_h.proto);
  328                         mob_h.hcrc = gre_in_cksum((u_int16_t *)&mob_h, msiz);
  329 
  330                         if ((m->m_data - msiz) < m->m_pktdat) {
  331                                 /* need new mbuf */
  332                                 MGETHDR(m0, M_DONTWAIT, MT_DATA);
  333                                 if (m0 == NULL) {
  334                                         _IF_DROP(&ifp->if_snd);
  335                                         m_freem(m);
  336                                         error = ENOBUFS;
  337                                         goto end;
  338                                 }
  339                                 m0->m_next = m;
  340                                 m->m_data += sizeof(struct ip);
  341                                 m->m_len -= sizeof(struct ip);
  342                                 m0->m_pkthdr.len = m->m_pkthdr.len + msiz;
  343                                 m0->m_len = msiz + sizeof(struct ip);
  344                                 m0->m_data += max_linkhdr;
  345                                 memcpy(mtod(m0, caddr_t), (caddr_t)ip,
  346                                        sizeof(struct ip));
  347                                 m = m0;
  348                         } else {  /* we have some space left in the old one */
  349                                 m->m_data -= msiz;
  350                                 m->m_len += msiz;
  351                                 m->m_pkthdr.len += msiz;
  352                                 bcopy(ip, mtod(m, caddr_t),
  353                                         sizeof(struct ip));
  354                         }
  355                         ip = mtod(m, struct ip *);
  356                         memcpy((caddr_t)(ip + 1), &mob_h, (unsigned)msiz);
  357                         ip->ip_len = ntohs(ip->ip_len) + msiz;
  358                 } else {  /* AF_INET */
  359                         _IF_DROP(&ifp->if_snd);
  360                         m_freem(m);
  361                         error = EINVAL;
  362                         goto end;
  363                 }
  364         } else if (sc->g_proto == IPPROTO_GRE) {
  365                 switch (dst->sa_family) {
  366                 case AF_INET:
  367                         ip = mtod(m, struct ip *);
  368                         gre_ip_tos = ip->ip_tos;
  369                         gre_ip_id = ip->ip_id;
  370                         if (sc->wccp_ver == WCCP_V2) {
  371                                 extra = sizeof(uint32_t);
  372                                 etype =  WCCP_PROTOCOL_TYPE;
  373                         } else {
  374                                 etype = ETHERTYPE_IP;
  375                         }
  376                         break;
  377 #ifdef INET6
  378                 case AF_INET6:
  379                         gre_ip_id = ip_newid();
  380                         etype = ETHERTYPE_IPV6;
  381                         break;
  382 #endif
  383 #ifdef NETATALK
  384                 case AF_APPLETALK:
  385                         etype = ETHERTYPE_ATALK;
  386                         break;
  387 #endif
  388                 default:
  389                         _IF_DROP(&ifp->if_snd);
  390                         m_freem(m);
  391                         error = EAFNOSUPPORT;
  392                         goto end;
  393                 }
  394                         
  395                 /* Reserve space for GRE header + optional GRE key */
  396                 int hdrlen = sizeof(struct greip) + extra;
  397                 if (sc->key)
  398                         hdrlen += sizeof(uint32_t);
  399                 M_PREPEND(m, hdrlen, M_DONTWAIT);
  400         } else {
  401                 _IF_DROP(&ifp->if_snd);
  402                 m_freem(m);
  403                 error = EINVAL;
  404                 goto end;
  405         }
  406 
  407         if (m == NULL) {        /* mbuf allocation failed */
  408                 _IF_DROP(&ifp->if_snd);
  409                 error = ENOBUFS;
  410                 goto end;
  411         }
  412 
  413         M_SETFIB(m, sc->gre_fibnum); /* The envelope may use a different FIB */
  414 
  415         gh = mtod(m, struct greip *);
  416         if (sc->g_proto == IPPROTO_GRE) {
  417                 uint32_t *options = gh->gi_options;
  418 
  419                 memset((void *)gh, 0, sizeof(struct greip) + extra);
  420                 gh->gi_ptype = htons(etype);
  421                 gh->gi_flags = 0;
  422 
  423                 /* Add key option */
  424                 if (sc->key)
  425                 {
  426                         gh->gi_flags |= htons(GRE_KP);
  427                         *(options++) = htonl(sc->key);
  428                 }
  429         }
  430 
  431         gh->gi_pr = sc->g_proto;
  432         if (sc->g_proto != IPPROTO_MOBILE) {
  433                 gh->gi_src = sc->g_src;
  434                 gh->gi_dst = sc->g_dst;
  435                 ((struct ip*)gh)->ip_v = IPPROTO_IPV4;
  436                 ((struct ip*)gh)->ip_hl = (sizeof(struct ip)) >> 2;
  437                 ((struct ip*)gh)->ip_ttl = GRE_TTL;
  438                 ((struct ip*)gh)->ip_tos = gre_ip_tos;
  439                 ((struct ip*)gh)->ip_id = gre_ip_id;
  440                 gh->gi_len = m->m_pkthdr.len;
  441         }
  442 
  443         ifp->if_opackets++;
  444         ifp->if_obytes += m->m_pkthdr.len;
  445         /*
  446          * Send it off and with IP_FORWARD flag to prevent it from
  447          * overwriting the ip_id again.  ip_id is already set to the
  448          * ip_id of the encapsulated packet.
  449          */
  450         error = ip_output(m, NULL, &sc->route, IP_FORWARDING,
  451             (struct ip_moptions *)NULL, (struct inpcb *)NULL);
  452   end:
  453         sc->called = 0;
  454         if (error)
  455                 ifp->if_oerrors++;
  456         return (error);
  457 }
  458 
  459 static int
  460 gre_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
  461 {
  462         struct ifreq *ifr = (struct ifreq *)data;
  463         struct if_laddrreq *lifr = (struct if_laddrreq *)data;
  464         struct in_aliasreq *aifr = (struct in_aliasreq *)data;
  465         struct gre_softc *sc = ifp->if_softc;
  466         int s;
  467         struct sockaddr_in si;
  468         struct sockaddr *sa = NULL;
  469         int error, adj;
  470         struct sockaddr_in sp, sm, dp, dm;
  471         uint32_t key;
  472 
  473         error = 0;
  474         adj = 0;
  475 
  476         s = splnet();
  477         switch (cmd) {
  478         case SIOCSIFADDR:
  479                 ifp->if_flags |= IFF_UP;
  480                 break;
  481         case SIOCSIFDSTADDR:
  482                 break;
  483         case SIOCSIFFLAGS:
  484                 /*
  485                  * XXXRW: Isn't this priv_check() redundant to the ifnet
  486                  * layer check?
  487                  */
  488                 if ((error = priv_check(curthread, PRIV_NET_SETIFFLAGS)) != 0)
  489                         break;
  490                 if ((ifr->ifr_flags & IFF_LINK0) != 0)
  491                         sc->g_proto = IPPROTO_GRE;
  492                 else
  493                         sc->g_proto = IPPROTO_MOBILE;
  494                 if ((ifr->ifr_flags & IFF_LINK2) != 0)
  495                         sc->wccp_ver = WCCP_V2;
  496                 else
  497                         sc->wccp_ver = WCCP_V1;
  498                 goto recompute;
  499         case SIOCSIFMTU:
  500                 /*
  501                  * XXXRW: Isn't this priv_check() redundant to the ifnet
  502                  * layer check?
  503                  */
  504                 if ((error = priv_check(curthread, PRIV_NET_SETIFMTU)) != 0)
  505                         break;
  506                 if (ifr->ifr_mtu < 576) {
  507                         error = EINVAL;
  508                         break;
  509                 }
  510                 ifp->if_mtu = ifr->ifr_mtu;
  511                 break;
  512         case SIOCGIFMTU:
  513                 ifr->ifr_mtu = GRE2IFP(sc)->if_mtu;
  514                 break;
  515         case SIOCADDMULTI:
  516                 /*
  517                  * XXXRW: Isn't this priv_checkr() redundant to the ifnet
  518                  * layer check?
  519                  */
  520                 if ((error = priv_check(curthread, PRIV_NET_ADDMULTI)) != 0)
  521                         break;
  522                 if (ifr == 0) {
  523                         error = EAFNOSUPPORT;
  524                         break;
  525                 }
  526                 switch (ifr->ifr_addr.sa_family) {
  527 #ifdef INET
  528                 case AF_INET:
  529                         break;
  530 #endif
  531 #ifdef INET6
  532                 case AF_INET6:
  533                         break;
  534 #endif
  535                 default:
  536                         error = EAFNOSUPPORT;
  537                         break;
  538                 }
  539                 break;
  540         case SIOCDELMULTI:
  541                 /*
  542                  * XXXRW: Isn't this priv_check() redundant to the ifnet
  543                  * layer check?
  544                  */
  545                 if ((error = priv_check(curthread, PRIV_NET_DELIFGROUP)) != 0)
  546                         break;
  547                 if (ifr == 0) {
  548                         error = EAFNOSUPPORT;
  549                         break;
  550                 }
  551                 switch (ifr->ifr_addr.sa_family) {
  552 #ifdef INET
  553                 case AF_INET:
  554                         break;
  555 #endif
  556 #ifdef INET6
  557                 case AF_INET6:
  558                         break;
  559 #endif
  560                 default:
  561                         error = EAFNOSUPPORT;
  562                         break;
  563                 }
  564                 break;
  565         case GRESPROTO:
  566                 /*
  567                  * XXXRW: Isn't this priv_check() redundant to the ifnet
  568                  * layer check?
  569                  */
  570                 if ((error = priv_check(curthread, PRIV_NET_GRE)) != 0)
  571                         break;
  572                 sc->g_proto = ifr->ifr_flags;
  573                 switch (sc->g_proto) {
  574                 case IPPROTO_GRE:
  575                         ifp->if_flags |= IFF_LINK0;
  576                         break;
  577                 case IPPROTO_MOBILE:
  578                         ifp->if_flags &= ~IFF_LINK0;
  579                         break;
  580                 default:
  581                         error = EPROTONOSUPPORT;
  582                         break;
  583                 }
  584                 goto recompute;
  585         case GREGPROTO:
  586                 ifr->ifr_flags = sc->g_proto;
  587                 break;
  588         case GRESADDRS:
  589         case GRESADDRD:
  590                 error = priv_check(curthread, PRIV_NET_GRE);
  591                 if (error)
  592                         return (error);
  593                 /*
  594                  * set tunnel endpoints, compute a less specific route
  595                  * to the remote end and mark if as up
  596                  */
  597                 sa = &ifr->ifr_addr;
  598                 if (cmd == GRESADDRS)
  599                         sc->g_src = (satosin(sa))->sin_addr;
  600                 if (cmd == GRESADDRD)
  601                         sc->g_dst = (satosin(sa))->sin_addr;
  602         recompute:
  603 #ifdef INET
  604                 if (sc->encap != NULL) {
  605                         encap_detach(sc->encap);
  606                         sc->encap = NULL;
  607                 }
  608 #endif
  609                 if ((sc->g_src.s_addr != INADDR_ANY) &&
  610                     (sc->g_dst.s_addr != INADDR_ANY)) {
  611                         bzero(&sp, sizeof(sp));
  612                         bzero(&sm, sizeof(sm));
  613                         bzero(&dp, sizeof(dp));
  614                         bzero(&dm, sizeof(dm));
  615                         sp.sin_len = sm.sin_len = dp.sin_len = dm.sin_len =
  616                             sizeof(struct sockaddr_in);
  617                         sp.sin_family = sm.sin_family = dp.sin_family =
  618                             dm.sin_family = AF_INET;
  619                         sp.sin_addr = sc->g_src;
  620                         dp.sin_addr = sc->g_dst;
  621                         sm.sin_addr.s_addr = dm.sin_addr.s_addr =
  622                             INADDR_BROADCAST;
  623 #ifdef INET
  624                         sc->encap = encap_attach(AF_INET, sc->g_proto,
  625                             sintosa(&sp), sintosa(&sm), sintosa(&dp),
  626                             sintosa(&dm), (sc->g_proto == IPPROTO_GRE) ?
  627                                 &in_gre_protosw : &in_mobile_protosw, sc);
  628                         if (sc->encap == NULL)
  629                                 printf("%s: unable to attach encap\n",
  630                                     if_name(GRE2IFP(sc)));
  631 #endif
  632                         if (sc->route.ro_rt != 0) /* free old route */
  633                                 RTFREE(sc->route.ro_rt);
  634                         if (gre_compute_route(sc) == 0)
  635                                 ifp->if_drv_flags |= IFF_DRV_RUNNING;
  636                         else
  637                                 ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
  638                 }
  639                 break;
  640         case GREGADDRS:
  641                 memset(&si, 0, sizeof(si));
  642                 si.sin_family = AF_INET;
  643                 si.sin_len = sizeof(struct sockaddr_in);
  644                 si.sin_addr.s_addr = sc->g_src.s_addr;
  645                 sa = sintosa(&si);
  646                 ifr->ifr_addr = *sa;
  647                 break;
  648         case GREGADDRD:
  649                 memset(&si, 0, sizeof(si));
  650                 si.sin_family = AF_INET;
  651                 si.sin_len = sizeof(struct sockaddr_in);
  652                 si.sin_addr.s_addr = sc->g_dst.s_addr;
  653                 sa = sintosa(&si);
  654                 ifr->ifr_addr = *sa;
  655                 break;
  656         case SIOCSIFPHYADDR:
  657                 /*
  658                  * XXXRW: Isn't this priv_check() redundant to the ifnet
  659                  * layer check?
  660                  */
  661                 if ((error = priv_check(curthread, PRIV_NET_SETIFPHYS)) != 0)
  662                         break;
  663                 if (aifr->ifra_addr.sin_family != AF_INET ||
  664                     aifr->ifra_dstaddr.sin_family != AF_INET) {
  665                         error = EAFNOSUPPORT;
  666                         break;
  667                 }
  668                 if (aifr->ifra_addr.sin_len != sizeof(si) ||
  669                     aifr->ifra_dstaddr.sin_len != sizeof(si)) {
  670                         error = EINVAL;
  671                         break;
  672                 }
  673                 sc->g_src = aifr->ifra_addr.sin_addr;
  674                 sc->g_dst = aifr->ifra_dstaddr.sin_addr;
  675                 goto recompute;
  676         case SIOCSLIFPHYADDR:
  677                 /*
  678                  * XXXRW: Isn't this priv_check() redundant to the ifnet
  679                  * layer check?
  680                  */
  681                 if ((error = priv_check(curthread, PRIV_NET_SETIFPHYS)) != 0)
  682                         break;
  683                 if (lifr->addr.ss_family != AF_INET ||
  684                     lifr->dstaddr.ss_family != AF_INET) {
  685                         error = EAFNOSUPPORT;
  686                         break;
  687                 }
  688                 if (lifr->addr.ss_len != sizeof(si) ||
  689                     lifr->dstaddr.ss_len != sizeof(si)) {
  690                         error = EINVAL;
  691                         break;
  692                 }
  693                 sc->g_src = (satosin(&lifr->addr))->sin_addr;
  694                 sc->g_dst =
  695                     (satosin(&lifr->dstaddr))->sin_addr;
  696                 goto recompute;
  697         case SIOCDIFPHYADDR:
  698                 /*
  699                  * XXXRW: Isn't this priv_check() redundant to the ifnet
  700                  * layer check?
  701                  */
  702                 if ((error = priv_check(curthread, PRIV_NET_SETIFPHYS)) != 0)
  703                         break;
  704                 sc->g_src.s_addr = INADDR_ANY;
  705                 sc->g_dst.s_addr = INADDR_ANY;
  706                 goto recompute;
  707         case SIOCGLIFPHYADDR:
  708                 if (sc->g_src.s_addr == INADDR_ANY ||
  709                     sc->g_dst.s_addr == INADDR_ANY) {
  710                         error = EADDRNOTAVAIL;
  711                         break;
  712                 }
  713                 memset(&si, 0, sizeof(si));
  714                 si.sin_family = AF_INET;
  715                 si.sin_len = sizeof(struct sockaddr_in);
  716                 si.sin_addr.s_addr = sc->g_src.s_addr;
  717                 memcpy(&lifr->addr, &si, sizeof(si));
  718                 si.sin_addr.s_addr = sc->g_dst.s_addr;
  719                 memcpy(&lifr->dstaddr, &si, sizeof(si));
  720                 break;
  721         case SIOCGIFPSRCADDR:
  722 #ifdef INET6
  723         case SIOCGIFPSRCADDR_IN6:
  724 #endif
  725                 if (sc->g_src.s_addr == INADDR_ANY) {
  726                         error = EADDRNOTAVAIL;
  727                         break;
  728                 }
  729                 memset(&si, 0, sizeof(si));
  730                 si.sin_family = AF_INET;
  731                 si.sin_len = sizeof(struct sockaddr_in);
  732                 si.sin_addr.s_addr = sc->g_src.s_addr;
  733                 bcopy(&si, &ifr->ifr_addr, sizeof(ifr->ifr_addr));
  734                 break;
  735         case SIOCGIFPDSTADDR:
  736 #ifdef INET6
  737         case SIOCGIFPDSTADDR_IN6:
  738 #endif
  739                 if (sc->g_dst.s_addr == INADDR_ANY) {
  740                         error = EADDRNOTAVAIL;
  741                         break;
  742                 }
  743                 memset(&si, 0, sizeof(si));
  744                 si.sin_family = AF_INET;
  745                 si.sin_len = sizeof(struct sockaddr_in);
  746                 si.sin_addr.s_addr = sc->g_dst.s_addr;
  747                 bcopy(&si, &ifr->ifr_addr, sizeof(ifr->ifr_addr));
  748                 break;
  749         case GRESKEY:
  750                 error = priv_check(curthread, PRIV_NET_GRE);
  751                 if (error)
  752                         break;
  753                 error = copyin(ifr->ifr_data, &key, sizeof(key));
  754                 if (error)
  755                         break;
  756                 /* adjust MTU for option header */
  757                 if (key == 0 && sc->key != 0)           /* clear */
  758                         adj += sizeof(key);
  759                 else if (key != 0 && sc->key == 0)      /* set */
  760                         adj -= sizeof(key);
  761 
  762                 if (ifp->if_mtu + adj < 576) {
  763                         error = EINVAL;
  764                         break;
  765                 }
  766                 ifp->if_mtu += adj;
  767                 sc->key = key;
  768                 break;
  769         case GREGKEY:
  770                 error = copyout(&sc->key, ifr->ifr_data, sizeof(sc->key));
  771                 break;
  772 
  773         default:
  774                 error = EINVAL;
  775                 break;
  776         }
  777 
  778         splx(s);
  779         return (error);
  780 }
  781 
  782 /*
  783  * computes a route to our destination that is not the one
  784  * which would be taken by ip_output(), as this one will loop back to
  785  * us. If the interface is p2p as  a--->b, then a routing entry exists
  786  * If we now send a packet to b (e.g. ping b), this will come down here
  787  * gets src=a, dst=b tacked on and would from ip_output() sent back to
  788  * if_gre.
  789  * Goal here is to compute a route to b that is less specific than
  790  * a-->b. We know that this one exists as in normal operation we have
  791  * at least a default route which matches.
  792  */
  793 static int
  794 gre_compute_route(struct gre_softc *sc)
  795 {
  796         struct route *ro;
  797 
  798         ro = &sc->route;
  799 
  800         memset(ro, 0, sizeof(struct route));
  801         ((struct sockaddr_in *)&ro->ro_dst)->sin_addr = sc->g_dst;
  802         ro->ro_dst.sa_family = AF_INET;
  803         ro->ro_dst.sa_len = sizeof(ro->ro_dst);
  804 
  805         /*
  806          * toggle last bit, so our interface is not found, but a less
  807          * specific route. I'd rather like to specify a shorter mask,
  808          * but this is not possible. Should work though. XXX
  809          * XXX MRT Use a different FIB for the tunnel to solve this problem.
  810          */
  811         if ((GRE2IFP(sc)->if_flags & IFF_LINK1) == 0) {
  812                 ((struct sockaddr_in *)&ro->ro_dst)->sin_addr.s_addr ^=
  813                     htonl(0x01);
  814         }
  815 
  816 #ifdef DIAGNOSTIC
  817         printf("%s: searching for a route to %s", if_name(GRE2IFP(sc)),
  818             inet_ntoa(((struct sockaddr_in *)&ro->ro_dst)->sin_addr));
  819 #endif
  820 
  821         rtalloc_fib(ro, sc->gre_fibnum);
  822 
  823         /*
  824          * check if this returned a route at all and this route is no
  825          * recursion to ourself
  826          */
  827         if (ro->ro_rt == NULL || ro->ro_rt->rt_ifp->if_softc == sc) {
  828 #ifdef DIAGNOSTIC
  829                 if (ro->ro_rt == NULL)
  830                         printf(" - no route found!\n");
  831                 else
  832                         printf(" - route loops back to ourself!\n");
  833 #endif
  834                 return EADDRNOTAVAIL;
  835         }
  836 
  837         /*
  838          * now change it back - else ip_output will just drop
  839          * the route and search one to this interface ...
  840          */
  841         if ((GRE2IFP(sc)->if_flags & IFF_LINK1) == 0)
  842                 ((struct sockaddr_in *)&ro->ro_dst)->sin_addr = sc->g_dst;
  843 
  844 #ifdef DIAGNOSTIC
  845         printf(", choosing %s with gateway %s", if_name(ro->ro_rt->rt_ifp),
  846             inet_ntoa(((struct sockaddr_in *)(ro->ro_rt->rt_gateway))->sin_addr));
  847         printf("\n");
  848 #endif
  849 
  850         return 0;
  851 }
  852 
  853 /*
  854  * do a checksum of a buffer - much like in_cksum, which operates on
  855  * mbufs.
  856  */
  857 u_int16_t
  858 gre_in_cksum(u_int16_t *p, u_int len)
  859 {
  860         u_int32_t sum = 0;
  861         int nwords = len >> 1;
  862 
  863         while (nwords-- != 0)
  864                 sum += *p++;
  865 
  866         if (len & 1) {
  867                 union {
  868                         u_short w;
  869                         u_char c[2];
  870                 } u;
  871                 u.c[0] = *(u_char *)p;
  872                 u.c[1] = 0;
  873                 sum += u.w;
  874         }
  875 
  876         /* end-around-carry */
  877         sum = (sum >> 16) + (sum & 0xffff);
  878         sum += (sum >> 16);
  879         return (~sum);
  880 }
  881 
  882 static int
  883 gremodevent(module_t mod, int type, void *data)
  884 {
  885 
  886         switch (type) {
  887         case MOD_LOAD:
  888                 greattach();
  889                 break;
  890         case MOD_UNLOAD:
  891                 if_clone_detach(&gre_cloner);
  892                 mtx_destroy(&gre_mtx);
  893                 break;
  894         default:
  895                 return EOPNOTSUPP;
  896         }
  897         return 0;
  898 }
  899 
  900 static moduledata_t gre_mod = {
  901         "if_gre",
  902         gremodevent,
  903         0
  904 };
  905 
  906 DECLARE_MODULE(if_gre, gre_mod, SI_SUB_PSEUDO, SI_ORDER_ANY);
  907 MODULE_VERSION(if_gre, 1);

Cache object: 03d29c676b41fd8b69830451d33b3a53


[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]


This page is part of the FreeBSD/Linux Linux Kernel Cross-Reference, and was automatically generated using a modified version of the LXR engine.