/* $NetBSD: ip_gre.c,v 1.34 2005/03/30 16:34:54 is Exp $ */ /* * Copyright (c) 1998 The NetBSD Foundation, Inc. * All rights reserved. * * This code is derived from software contributed to The NetBSD Foundation * by Heiko W.Rupp * * IPv6-over-GRE contributed by Gert Doering * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the NetBSD * Foundation, Inc. and its contributors. * 4. Neither the name of The NetBSD Foundation nor the names of its * contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ /* * deencapsulate tunneled packets and send them on * output half is in net/if_gre.[ch] * This currently handles IPPROTO_GRE, IPPROTO_MOBILE */ #include __KERNEL_RCSID(0, "$NetBSD: ip_gre.c,v 1.34 2005/03/30 16:34:54 is Exp $"); #include "gre.h" #if NGRE > 0 #include "opt_inet.h" #include "opt_ns.h" #include "opt_atalk.h" #include "bpfilter.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef INET #include #include #include #include #include #include #else #error ip_gre input without IP? #endif #ifdef NS #include #include #endif #ifdef NETATALK #include #include #include #endif /* Needs IP headers. */ #include #include #if 1 void gre_inet_ntoa(struct in_addr in); /* XXX */ #endif struct gre_softc *gre_lookup(struct mbuf *, u_int8_t); int gre_input2(struct mbuf *, int, u_char); /* * De-encapsulate a packet and feed it back through ip input (this * routine is called whenever IP gets a packet with proto type * IPPROTO_GRE and a local destination address). * This really is simple */ void gre_input(struct mbuf *m, ...) { int off, ret, proto; va_list ap; va_start(ap, m); off = va_arg(ap, int); proto = va_arg(ap, int); va_end(ap); ret = gre_input2(m, off, proto); /* * ret == 0 : packet not processed, meaning that * no matching tunnel that is up is found. * we inject it to raw ip socket to see if anyone picks it up. */ if (ret == 0) rip_input(m, off, proto); } /* * decapsulate. * Does the real work and is called from gre_input() (above) * returns 0 if packet is not yet processed * and 1 if it needs no further processing * proto is the protocol number of the "calling" foo_input() * routine. */ int gre_input2(struct mbuf *m, int hlen, u_char proto) { struct greip *gip; int s, isr; struct ifqueue *ifq; struct gre_softc *sc; u_int16_t flags; if ((sc = gre_lookup(m, proto)) == NULL) { /* No matching tunnel or tunnel is down. */ return (0); } if (m->m_len < sizeof(*gip)) { m = m_pullup(m, sizeof(*gip)); if (m == NULL) return (ENOBUFS); } gip = mtod(m, struct greip *); sc->sc_if.if_ipackets++; sc->sc_if.if_ibytes += m->m_pkthdr.len; switch (proto) { case IPPROTO_GRE: hlen += sizeof(struct gre_h); /* process GRE flags as packet can be of variable len */ flags = ntohs(gip->gi_flags); /* Checksum & Offset are present */ if ((flags & GRE_CP) | (flags & GRE_RP)) hlen += 4; /* We don't support routing fields (variable length) */ if (flags & GRE_RP) return (0); if (flags & GRE_KP) hlen += 4; if (flags & GRE_SP) hlen += 4; switch (ntohs(gip->gi_ptype)) { /* ethertypes */ case ETHERTYPE_IP: /* shouldn't need a schednetisr(), as */ ifq = &ipintrq; /* we are in ip_input */ isr = NETISR_IP; break; #ifdef NS case ETHERTYPE_NS: ifq = &nsintrq; isr = NETISR_NS; break; #endif #ifdef NETATALK case ETHERTYPE_ATALK: ifq = &atintrq1; isr = NETISR_ATALK; break; #endif #ifdef INET6 case ETHERTYPE_IPV6: #ifdef GRE_DEBUG printf( "ip_gre.c/gre_input2: IPv6 packet\n" ); #endif ifq = &ip6intrq; isr = NETISR_IPV6; break; #endif default: /* others not yet supported */ printf( "ip_gre.c/gre_input2: unhandled ethertype 0x%04x\n", (int) ntohs(gip->gi_ptype) ); return (0); } break; default: /* others not yet supported */ return (0); } if (hlen > m->m_pkthdr.len) { m_freem(m); return (EINVAL); } m_adj(m, hlen); #if NBPFILTER > 0 if (sc->sc_if.if_bpf) { struct mbuf m0; u_int32_t af = AF_INET; m0.m_flags = 0; m0.m_next = m; m0.m_len = 4; m0.m_data = (char *)⁡ bpf_mtap(sc->sc_if.if_bpf, &m0); } #endif /*NBPFILTER > 0*/ m->m_pkthdr.rcvif = &sc->sc_if; s = splnet(); /* possible */ if (IF_QFULL(ifq)) { IF_DROP(ifq); m_freem(m); } else { IF_ENQUEUE(ifq, m); } /* we need schednetisr since the address family may change */ schednetisr(isr); splx(s); return (1); /* packet is done, no further processing needed */ } /* * input routine for IPPRPOTO_MOBILE * This is a little bit diffrent from the other modes, as the * encapsulating header was not prepended, but instead inserted * between IP header and payload */ void gre_mobile_input(struct mbuf *m, ...) { struct ip *ip; struct mobip_h *mip; struct ifqueue *ifq; struct gre_softc *sc; int hlen, s; va_list ap; int msiz; va_start(ap, m); hlen = va_arg(ap, int); va_end(ap); if ((sc = gre_lookup(m, IPPROTO_MOBILE)) == NULL) { /* No matching tunnel or tunnel is down. */ m_freem(m); return; } if (m->m_len < sizeof(*mip)) { m = m_pullup(m, sizeof(*mip)); if (m == NULL) return; } ip = mtod(m, struct ip *); mip = mtod(m, struct mobip_h *); sc->sc_if.if_ipackets++; sc->sc_if.if_ibytes += m->m_pkthdr.len; if (ntohs(mip->mh.proto) & MOB_H_SBIT) { msiz = MOB_H_SIZ_L; mip->mi.ip_src.s_addr = mip->mh.osrc; } else msiz = MOB_H_SIZ_S; if (m->m_len < (ip->ip_hl << 2) + msiz) { m = m_pullup(m, (ip->ip_hl << 2) + msiz); if (m == NULL) return; ip = mtod(m, struct ip *); mip = mtod(m, struct mobip_h *); } mip->mi.ip_dst.s_addr = mip->mh.odst; mip->mi.ip_p = (ntohs(mip->mh.proto) >> 8); if (gre_in_cksum((u_int16_t *)&mip->mh, msiz) != 0) { m_freem(m); return; } memmove(ip + (ip->ip_hl << 2), ip + (ip->ip_hl << 2) + msiz, m->m_len - msiz - (ip->ip_hl << 2)); m->m_len -= msiz; ip->ip_len = htons(ntohs(ip->ip_len) - msiz); m->m_pkthdr.len -= msiz; ip->ip_sum = 0; ip->ip_sum = in_cksum(m, (ip->ip_hl << 2)); #if NBPFILTER > 0 if (sc->sc_if.if_bpf) { struct mbuf m0; u_int af = AF_INET; m0.m_next = m; m0.m_len = 4; m0.m_data = (char *)⁡ bpf_mtap(sc->sc_if.if_bpf, &m0); } #endif /*NBPFILTER > 0*/ ifq = &ipintrq; s = splnet(); /* possible */ if (IF_QFULL(ifq)) { IF_DROP(ifq); m_freem(m); } else { IF_ENQUEUE(ifq, m); } splx(s); } /* * Find the gre interface associated with our src/dst/proto set. */ struct gre_softc * gre_lookup(struct mbuf *m, u_int8_t proto) { struct ip *ip = mtod(m, struct ip *); struct gre_softc *sc; for (sc = LIST_FIRST(&gre_softc_list); sc != NULL; sc = LIST_NEXT(sc, sc_list)) { if ((sc->g_dst.s_addr == ip->ip_src.s_addr) && (sc->g_src.s_addr == ip->ip_dst.s_addr) && (sc->g_proto == proto) && ((sc->sc_if.if_flags & IFF_UP) != 0)) return (sc); } return (NULL); } #endif /* if NGRE > 0 */