ip_gre.c

Version: - FREEBSD - FREEBSD-13-STABLE - FREEBSD-13-0 - FREEBSD-12-STABLE - FREEBSD-12-0 - FREEBSD-11-STABLE - FREEBSD-11-0 - FREEBSD-10-STABLE - FREEBSD-10-0 - FREEBSD-9-STABLE - FREEBSD-9-0 - FREEBSD-8-STABLE - FREEBSD-8-0 - FREEBSD-7-STABLE - FREEBSD-7-0 - FREEBSD-6-STABLE - FREEBSD-6-0 - FREEBSD-5-STABLE - FREEBSD-5-0 - FREEBSD-4-STABLE - FREEBSD-3-STABLE - FREEBSD22 - l41 - OPENBSD - linux-2.6 - MK84 - PLAN9 - xnu-8792
SearchContext: - none - 3 - 10
    1 /*      $NetBSD: ip_gre.c,v 1.29 2003/09/05 23:02:43 itojun Exp $ */
    2 /*       $FreeBSD: releng/5.3/sys/netinet/ip_gre.c 136588 2004-10-16 08:43:07Z cvs2svn $ */
    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  * Redistribution and use in source and binary forms, with or without
   12  * modification, are permitted provided that the following conditions
   13  * are met:
   14  * 1. Redistributions of source code must retain the above copyright
   15  *    notice, this list of conditions and the following disclaimer.
   16  * 2. Redistributions in binary form must reproduce the above copyright
   17  *    notice, this list of conditions and the following disclaimer in the
   18  *    documentation and/or other materials provided with the distribution.
   19  * 3. All advertising materials mentioning features or use of this software
   20  *    must display the following acknowledgement:
   21  *        This product includes software developed by the NetBSD
   22  *        Foundation, Inc. and its contributors.
   23  * 4. Neither the name of The NetBSD Foundation nor the names of its
   24  *    contributors may be used to endorse or promote products derived
   25  *    from this software without specific prior written permission.
   26  *
   27  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
   28  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
   29  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
   30  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
   31  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
   32  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
   33  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
   34  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
   35  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
   36  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
   37  * POSSIBILITY OF SUCH DAMAGE.
   38  */
   39 
   40 /*
   41  * deencapsulate tunneled packets and send them on
   42  * output half is in net/if_gre.[ch]
   43  * This currently handles IPPROTO_GRE, IPPROTO_MOBILE
   44  */
   45 
   46 #include "opt_inet.h"
   47 #include "opt_atalk.h"
   48 
   49 #include <sys/param.h>
   50 #include <sys/systm.h>
   51 #include <sys/mbuf.h>
   52 #include <sys/socket.h>
   53 #include <sys/socketvar.h>
   54 #include <sys/protosw.h>
   55 #include <sys/errno.h>
   56 #include <sys/time.h>
   57 #include <sys/kernel.h>
   58 #include <sys/syslog.h>
   59 #include <net/bpf.h>
   60 #include <net/ethernet.h>
   61 #include <net/if.h>
   62 #include <net/netisr.h>
   63 #include <net/route.h>
   64 #include <net/raw_cb.h>
   65 
   66 #ifdef INET
   67 #include <netinet/in.h>
   68 #include <netinet/in_var.h>
   69 #include <netinet/in_systm.h>
   70 #include <netinet/ip.h>
   71 #include <netinet/ip_var.h>
   72 #include <netinet/ip_gre.h>
   73 #include <machine/in_cksum.h>
   74 #else
   75 #error ip_gre input without IP?
   76 #endif
   77 
   78 #ifdef NETATALK
   79 #include <netatalk/at.h>
   80 #include <netatalk/at_var.h>
   81 #include <netatalk/at_extern.h>
   82 #endif
   83 
   84 /* Needs IP headers. */
   85 #include <net/if_gre.h>
   86 
   87 #include <machine/stdarg.h>
   88 
   89 #if 1
   90 void gre_inet_ntoa(struct in_addr in);  /* XXX */
   91 #endif
   92 
   93 static struct gre_softc *gre_lookup(struct mbuf *, u_int8_t);
   94 
   95 static int      gre_input2(struct mbuf *, int, u_char);
   96 
   97 /*
   98  * De-encapsulate a packet and feed it back through ip input (this
   99  * routine is called whenever IP gets a packet with proto type
  100  * IPPROTO_GRE and a local destination address).
  101  * This really is simple
  102  */
  103 void
  104 #if __STDC__
  105 gre_input(struct mbuf *m, ...)
  106 #else
  107 gre_input(m, va_alist)
  108         struct mbuf *m;
  109         va_dcl
  110 #endif
  111 {
  112         int off, ret, proto;
  113         va_list ap;
  114 
  115         va_start(ap, m);
  116         off = va_arg(ap, int);
  117         va_end(ap);
  118         proto = (mtod(m, struct ip *))->ip_p;
  119 
  120         ret = gre_input2(m, off, proto);
  121         /*
  122          * ret == 0 : packet not processed, meaning that
  123          * no matching tunnel that is up is found.
  124          * we inject it to raw ip socket to see if anyone picks it up.
  125          */
  126         if (ret == 0)
  127                 rip_input(m, off);
  128 }
  129 
  130 /*
  131  * decapsulate.
  132  * Does the real work and is called from gre_input() (above)
  133  * returns 0 if packet is not yet processed
  134  * and 1 if it needs no further processing
  135  * proto is the protocol number of the "calling" foo_input()
  136  * routine.
  137  */
  138 static int
  139 gre_input2(struct mbuf *m ,int hlen, u_char proto)
  140 {
  141         struct greip *gip;
  142         int isr;
  143         struct gre_softc *sc;
  144         u_int16_t flags;
  145 
  146         if ((sc = gre_lookup(m, proto)) == NULL) {
  147                 /* No matching tunnel or tunnel is down. */
  148                 return (0);
  149         }
  150 
  151         if (m->m_len < sizeof(*gip)) {
  152                 m = m_pullup(m, sizeof(*gip));
  153                 if (m == NULL)
  154                         return (ENOBUFS);
  155         }
  156         gip = mtod(m, struct greip *);
  157 
  158         sc->sc_if.if_ipackets++;
  159         sc->sc_if.if_ibytes += m->m_pkthdr.len;
  160 
  161         switch (proto) {
  162         case IPPROTO_GRE:
  163                 hlen += sizeof(struct gre_h);
  164 
  165                 /* process GRE flags as packet can be of variable len */
  166                 flags = ntohs(gip->gi_flags);
  167 
  168                 /* Checksum & Offset are present */
  169                 if ((flags & GRE_CP) | (flags & GRE_RP))
  170                         hlen += 4;
  171                 /* We don't support routing fields (variable length) */
  172                 if (flags & GRE_RP)
  173                         return (0);
  174                 if (flags & GRE_KP)
  175                         hlen += 4;
  176                 if (flags & GRE_SP)
  177                         hlen += 4;
  178 
  179                 switch (ntohs(gip->gi_ptype)) { /* ethertypes */
  180                 case WCCP_PROTOCOL_TYPE:
  181                         if (sc->wccp_ver == WCCP_V2)
  182                                 hlen += 4;
  183                         /* FALLTHROUGH */
  184                 case ETHERTYPE_IP:      /* shouldn't need a schednetisr(), */
  185                         isr = NETISR_IP;/* as we are in ip_input */
  186                         break;
  187 #ifdef NETATALK
  188                 case ETHERTYPE_ATALK:
  189                         isr = NETISR_ATALK1;
  190                         break;
  191 #endif
  192                 case ETHERTYPE_IPV6:
  193                         /* FALLTHROUGH */
  194                 default:           /* others not yet supported */
  195                         return (0);
  196                 }
  197                 break;
  198         default:
  199                 /* others not yet supported */
  200                 return (0);
  201         }
  202 
  203         if (hlen > m->m_pkthdr.len) {
  204                 m_freem(m);
  205                 return (EINVAL);
  206         }
  207         /* Unlike NetBSD, in FreeBSD m_adj() adjusts m->m_pkthdr.len as well */
  208         m_adj(m, hlen);
  209 
  210         if (sc->sc_if.if_bpf) {
  211                 u_int32_t af = AF_INET;
  212                 bpf_mtap2(sc->sc_if.if_bpf, &af, sizeof(af), m);
  213         }
  214 
  215         m->m_pkthdr.rcvif = &sc->sc_if;
  216 
  217         netisr_dispatch(isr, m);
  218 
  219         return (1);     /* packet is done, no further processing needed */
  220 }
  221 
  222 /*
  223  * input routine for IPPRPOTO_MOBILE
  224  * This is a little bit diffrent from the other modes, as the
  225  * encapsulating header was not prepended, but instead inserted
  226  * between IP header and payload
  227  */
  228 
  229 void
  230 #if __STDC__
  231 gre_mobile_input(struct mbuf *m, ...)
  232 #else
  233 gre_mobile_input(m, va_alist)
  234         struct mbuf *m;
  235         va_dcl
  236 #endif
  237 {
  238         struct ip *ip;
  239         struct mobip_h *mip;
  240         struct gre_softc *sc;
  241         int hlen;
  242         va_list ap;
  243         int msiz;
  244 
  245         va_start(ap, m);
  246         hlen = va_arg(ap, int);
  247         va_end(ap);
  248 
  249         if ((sc = gre_lookup(m, IPPROTO_MOBILE)) == NULL) {
  250                 /* No matching tunnel or tunnel is down. */
  251                 m_freem(m);
  252                 return;
  253         }
  254 
  255         if (m->m_len < sizeof(*mip)) {
  256                 m = m_pullup(m, sizeof(*mip));
  257                 if (m == NULL)
  258                         return;
  259         }
  260         ip = mtod(m, struct ip *);
  261         mip = mtod(m, struct mobip_h *);
  262 
  263         sc->sc_if.if_ipackets++;
  264         sc->sc_if.if_ibytes += m->m_pkthdr.len;
  265 
  266         if (ntohs(mip->mh.proto) & MOB_H_SBIT) {
  267                 msiz = MOB_H_SIZ_L;
  268                 mip->mi.ip_src.s_addr = mip->mh.osrc;
  269         } else
  270                 msiz = MOB_H_SIZ_S;
  271 
  272         if (m->m_len < (ip->ip_hl << 2) + msiz) {
  273                 m = m_pullup(m, (ip->ip_hl << 2) + msiz);
  274                 if (m == NULL)
  275                         return;
  276                 ip = mtod(m, struct ip *);
  277                 mip = mtod(m, struct mobip_h *);
  278         }
  279 
  280         mip->mi.ip_dst.s_addr = mip->mh.odst;
  281         mip->mi.ip_p = (ntohs(mip->mh.proto) >> 8);
  282 
  283         if (gre_in_cksum((u_int16_t *)&mip->mh, msiz) != 0) {
  284                 m_freem(m);
  285                 return;
  286         }
  287 
  288         bcopy((caddr_t)(ip) + (ip->ip_hl << 2) + msiz, (caddr_t)(ip) +
  289             (ip->ip_hl << 2), m->m_len - msiz - (ip->ip_hl << 2));
  290         m->m_len -= msiz;
  291         m->m_pkthdr.len -= msiz;
  292 
  293         /*
  294          * On FreeBSD, rip_input() supplies us with ip->ip_len
  295          * already converted into host byteorder and also decreases
  296          * it by the lengh of IP header, however, ip_input() expects
  297          * that this field is in the original format (network byteorder
  298          * and full size of IP packet), so that adjust accordingly.
  299          */
  300         ip->ip_len = htons(ip->ip_len + sizeof(struct ip) - msiz);
  301 
  302         ip->ip_sum = 0;
  303         ip->ip_sum = in_cksum(m, (ip->ip_hl << 2));
  304 
  305         if (sc->sc_if.if_bpf) {
  306                 u_int32_t af = AF_INET;
  307                 bpf_mtap2(sc->sc_if.if_bpf, &af, sizeof(af), m);
  308         }
  309 
  310         m->m_pkthdr.rcvif = &sc->sc_if;
  311 
  312         netisr_dispatch(NETISR_IP, m);
  313 }
  314 
  315 /*
  316  * Find the gre interface associated with our src/dst/proto set.
  317  *
  318  * XXXRW: Need some sort of drain/refcount mechanism so that the softc
  319  * reference remains valid after it's returned from gre_lookup().  Right
  320  * now, I'm thinking it should be reference-counted with a gre_dropref()
  321  * when the caller is done with the softc.  This is complicated by how
  322  * to handle destroying the gre softc; probably using a gre_drain() in
  323  * in_gre.c during destroy.
  324  */
  325 static struct gre_softc *
  326 gre_lookup(m, proto)
  327         struct mbuf *m;
  328         u_int8_t proto;
  329 {
  330         struct ip *ip = mtod(m, struct ip *);
  331         struct gre_softc *sc;
  332 
  333         mtx_lock(&gre_mtx);
  334         for (sc = LIST_FIRST(&gre_softc_list); sc != NULL;
  335              sc = LIST_NEXT(sc, sc_list)) {
  336                 if ((sc->g_dst.s_addr == ip->ip_src.s_addr) &&
  337                     (sc->g_src.s_addr == ip->ip_dst.s_addr) &&
  338                     (sc->g_proto == proto) &&
  339                     ((sc->sc_if.if_flags & IFF_UP) != 0)) {
  340                         mtx_unlock(&gre_mtx);
  341                         return (sc);
  342                 }
  343         }
  344         mtx_unlock(&gre_mtx);
  345 
  346         return (NULL);
  347 }
Cache object: 4e39311264a8c8e101b75c97d79c78a2
[ 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.
FreeBSD/Linux Kernel Cross Reference sys/netinet/ip_gre.c

FreeBSD/Linux Kernel Cross Reference
sys/netinet/ip_gre.c
