in6_gif.c revision 283852
1139826Simp/*- 254263Sshin * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 354263Sshin * All rights reserved. 454263Sshin * 554263Sshin * Redistribution and use in source and binary forms, with or without 654263Sshin * modification, are permitted provided that the following conditions 754263Sshin * are met: 854263Sshin * 1. Redistributions of source code must retain the above copyright 954263Sshin * notice, this list of conditions and the following disclaimer. 1054263Sshin * 2. Redistributions in binary form must reproduce the above copyright 1154263Sshin * notice, this list of conditions and the following disclaimer in the 1254263Sshin * documentation and/or other materials provided with the distribution. 1354263Sshin * 3. Neither the name of the project nor the names of its contributors 1454263Sshin * may be used to endorse or promote products derived from this software 1554263Sshin * without specific prior written permission. 1654263Sshin * 1754263Sshin * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 1854263Sshin * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 1954263Sshin * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 2054263Sshin * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 2154263Sshin * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 2254263Sshin * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 2354263Sshin * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 2454263Sshin * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 2554263Sshin * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 2654263Sshin * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 2754263Sshin * SUCH DAMAGE. 28174510Sobrien * 29174510Sobrien * $KAME: in6_gif.c,v 1.49 2001/05/14 14:02:17 itojun Exp $ 3054263Sshin */ 3154263Sshin 32174510Sobrien#include <sys/cdefs.h> 33174510Sobrien__FBSDID("$FreeBSD: stable/10/sys/netinet6/in6_gif.c 283852 2015-05-31 22:58:41Z ae $"); 34174510Sobrien 3554263Sshin#include "opt_inet.h" 3662587Sitojun#include "opt_inet6.h" 3754263Sshin 3854263Sshin#include <sys/param.h> 39276149Sae#include <sys/lock.h> 40276149Sae#include <sys/rmlock.h> 4154263Sshin#include <sys/systm.h> 4254263Sshin#include <sys/socket.h> 4354263Sshin#include <sys/sockio.h> 4454263Sshin#include <sys/mbuf.h> 4554263Sshin#include <sys/errno.h> 46207369Sbz#include <sys/kernel.h> 4778064Sume#include <sys/queue.h> 4878064Sume#include <sys/syslog.h> 49207369Sbz#include <sys/sysctl.h> 50105293Sume#include <sys/protosw.h> 5178064Sume#include <sys/malloc.h> 5278064Sume 5354263Sshin#include <net/if.h> 54276149Sae#include <net/if_var.h> 5554263Sshin#include <net/route.h> 56276149Sae#include <net/vnet.h> 5754263Sshin 5854263Sshin#include <netinet/in.h> 5954263Sshin#include <netinet/in_systm.h> 6054263Sshin#ifdef INET 6154263Sshin#include <netinet/ip.h> 6254263Sshin#endif 6362587Sitojun#include <netinet/ip_encap.h> 6462587Sitojun#ifdef INET6 6562587Sitojun#include <netinet/ip6.h> 6654263Sshin#include <netinet6/ip6_var.h> 6754263Sshin#include <netinet6/in6_gif.h> 6862587Sitojun#include <netinet6/in6_var.h> 6962587Sitojun#endif 70105293Sume#include <netinet6/ip6protosw.h> 7155009Sshin#include <netinet/ip_ecn.h> 7262587Sitojun#ifdef INET6 7355009Sshin#include <netinet6/ip6_ecn.h> 7462587Sitojun#endif 7554263Sshin 7654263Sshin#include <net/if_gif.h> 7754263Sshin 78207369SbzVNET_DEFINE(int, ip6_gif_hlim) = GIF_HLIM; 79207369Sbz#define V_ip6_gif_hlim VNET(ip6_gif_hlim) 80207369Sbz 81207369SbzSYSCTL_DECL(_net_inet6_ip6); 82207369SbzSYSCTL_VNET_INT(_net_inet6_ip6, IPV6CTL_GIF_HLIM, gifhlim, CTLFLAG_RW, 83207369Sbz &VNET_NAME(ip6_gif_hlim), 0, ""); 84207369Sbz 85105293Sumestatic int gif_validate6(const struct ip6_hdr *, struct gif_softc *, 86105293Sume struct ifnet *); 87105293Sume 88105293Sumeextern struct domain inet6domain; 89186791Sbzstruct ip6protosw in6_gif_protosw = { 90186791Sbz .pr_type = SOCK_RAW, 91186791Sbz .pr_domain = &inet6domain, 92186791Sbz .pr_protocol = 0, /* IPPROTO_IPV[46] */ 93186791Sbz .pr_flags = PR_ATOMIC|PR_ADDR, 94186791Sbz .pr_input = in6_gif_input, 95186791Sbz .pr_output = rip6_output, 96186791Sbz .pr_ctloutput = rip6_ctloutput, 97186791Sbz .pr_usrreqs = &rip6_usrreqs 98105293Sume}; 99105293Sume 10054263Sshinint 101276149Saein6_gif_output(struct ifnet *ifp, struct mbuf *m, int proto, uint8_t ecn) 10254263Sshin{ 103276149Sae GIF_RLOCK_TRACKER; 104147256Sbrooks struct gif_softc *sc = ifp->if_softc; 10554263Sshin struct ip6_hdr *ip6; 106276149Sae int len; 10754263Sshin 10854263Sshin /* prepend new IP header */ 109189494Smarius len = sizeof(struct ip6_hdr); 110189494Smarius#ifndef __NO_STRICT_ALIGNMENT 111276149Sae if (proto == IPPROTO_ETHERIP) 112189494Smarius len += ETHERIP_ALIGN; 113189494Smarius#endif 114243882Sglebius M_PREPEND(m, len, M_NOWAIT); 115276149Sae if (m == NULL) 116276149Sae return (ENOBUFS); 117189494Smarius#ifndef __NO_STRICT_ALIGNMENT 118276149Sae if (proto == IPPROTO_ETHERIP) { 119189494Smarius len = mtod(m, vm_offset_t) & 3; 120189494Smarius KASSERT(len == 0 || len == ETHERIP_ALIGN, 121189494Smarius ("in6_gif_output: unexpected misalignment")); 122189494Smarius m->m_data += len; 123189494Smarius m->m_len -= ETHERIP_ALIGN; 124189494Smarius } 125189494Smarius#endif 12654263Sshin 12754263Sshin ip6 = mtod(m, struct ip6_hdr *); 128276149Sae GIF_RLOCK(sc); 129276149Sae if (sc->gif_family != AF_INET6) { 13078064Sume m_freem(m); 131276149Sae GIF_RUNLOCK(sc); 132276149Sae return (ENETDOWN); 13354263Sshin } 134276149Sae bcopy(sc->gif_ip6hdr, ip6, sizeof(struct ip6_hdr)); 135276149Sae GIF_RUNLOCK(sc); 13654263Sshin 137276149Sae ip6->ip6_flow |= htonl((uint32_t)ecn << 20); 138276149Sae ip6->ip6_nxt = proto; 139276149Sae ip6->ip6_hlim = V_ip6_gif_hlim; 14062587Sitojun /* 14162587Sitojun * force fragmentation to minimum MTU, to avoid path MTU discovery. 14262587Sitojun * it is too painful to ask for resend of inner packet, to achieve 14362587Sitojun * path MTU discovery for encapsulated packets. 14462587Sitojun */ 145276149Sae return (ip6_output(m, 0, NULL, IPV6_MINMTU, 0, NULL, NULL)); 14654263Sshin} 14754263Sshin 148120913Sumeint 149171259Sdelphijin6_gif_input(struct mbuf **mp, int *offp, int proto) 15054263Sshin{ 15154263Sshin struct mbuf *m = *mp; 152276149Sae struct ifnet *gifp; 153147507Sume struct gif_softc *sc; 15454263Sshin struct ip6_hdr *ip6; 155276149Sae uint8_t ecn; 15654263Sshin 157276149Sae sc = encap_getarg(m); 158147507Sume if (sc == NULL) { 159147507Sume m_freem(m); 160249294Sae IP6STAT_INC(ip6s_nogif); 161276149Sae return (IPPROTO_DONE); 162147507Sume } 163147507Sume gifp = GIF2IFP(sc); 164276149Sae if ((gifp->if_flags & IFF_UP) != 0) { 165276149Sae ip6 = mtod(m, struct ip6_hdr *); 166276149Sae ecn = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 167276149Sae m_adj(m, *offp); 168276149Sae gif_input(m, gifp, proto, ecn); 169276149Sae } else { 17054263Sshin m_freem(m); 171249294Sae IP6STAT_INC(ip6s_nogif); 17254263Sshin } 173276149Sae return (IPPROTO_DONE); 17454263Sshin} 17562587Sitojun 17662587Sitojun/* 177105293Sume * validate outer address. 17862587Sitojun */ 179105293Sumestatic int 180171259Sdelphijgif_validate6(const struct ip6_hdr *ip6, struct gif_softc *sc, 181171259Sdelphij struct ifnet *ifp) 18262587Sitojun{ 183283852Sae int ret; 18462587Sitojun 185276149Sae GIF_RLOCK_ASSERT(sc); 186105293Sume /* 187105293Sume * Check for address match. Note that the check is for an incoming 188105293Sume * packet. We should compare the *source* address in our configuration 189105293Sume * and the *destination* address of the packet, and vice versa. 190105293Sume */ 191283852Sae if (!IN6_ARE_ADDR_EQUAL(&sc->gif_ip6hdr->ip6_src, &ip6->ip6_dst)) 192276149Sae return (0); 193283852Sae ret = 128; 194283852Sae if (!IN6_ARE_ADDR_EQUAL(&sc->gif_ip6hdr->ip6_dst, &ip6->ip6_src)) { 195283852Sae if ((sc->gif_options & GIF_IGNORE_SOURCE) == 0) 196283852Sae return (0); 197283852Sae } else 198283852Sae ret += 128; 19962587Sitojun 20062587Sitojun /* martian filters on outer source - done in ip6_input */ 20162587Sitojun 20262587Sitojun /* ingress filters on outer source */ 203147256Sbrooks if ((GIF2IFP(sc)->if_flags & IFF_LINK2) == 0 && ifp) { 20462587Sitojun struct sockaddr_in6 sin6; 20562587Sitojun struct rtentry *rt; 20662587Sitojun 20762587Sitojun bzero(&sin6, sizeof(sin6)); 20862587Sitojun sin6.sin6_family = AF_INET6; 20962587Sitojun sin6.sin6_len = sizeof(struct sockaddr_in6); 210105293Sume sin6.sin6_addr = ip6->ip6_src; 211105293Sume sin6.sin6_scope_id = 0; /* XXX */ 212105293Sume 213231852Sbz rt = in6_rtalloc1((struct sockaddr *)&sin6, 0, 0UL, 214231852Sbz sc->gif_fibnum); 215105293Sume if (!rt || rt->rt_ifp != ifp) { 21678064Sume if (rt) 217187946Sbz RTFREE_LOCKED(rt); 218276149Sae return (0); 21962587Sitojun } 220187946Sbz RTFREE_LOCKED(rt); 22162587Sitojun } 22262587Sitojun 223283852Sae return (ret); 22462587Sitojun} 225105293Sume 226105293Sume/* 227105293Sume * we know that we are in IFF_UP, outer address available, and outer family 228105293Sume * matched the physical addr family. see gif_encapcheck(). 229105293Sume */ 230105293Sumeint 231276149Saein6_gif_encapcheck(const struct mbuf *m, int off, int proto, void *arg) 232105293Sume{ 233105293Sume struct ip6_hdr ip6; 234105293Sume struct gif_softc *sc; 235105293Sume struct ifnet *ifp; 236105293Sume 237105293Sume /* sanity check done in caller */ 238105293Sume sc = (struct gif_softc *)arg; 239276149Sae GIF_RLOCK_ASSERT(sc); 240105293Sume 241105293Sume m_copydata(m, 0, sizeof(ip6), (caddr_t)&ip6); 242105293Sume ifp = ((m->m_flags & M_PKTHDR) != 0) ? m->m_pkthdr.rcvif : NULL; 243276149Sae return (gif_validate6(&ip6, sc, ifp)); 244105293Sume} 245105293Sume 246105293Sumeint 247171259Sdelphijin6_gif_attach(struct gif_softc *sc) 248105293Sume{ 249276149Sae 250276149Sae KASSERT(sc->gif_ecookie == NULL, ("gif_ecookie isn't NULL")); 251276149Sae sc->gif_ecookie = encap_attach_func(AF_INET6, -1, gif_encapcheck, 252155333Sume (void *)&in6_gif_protosw, sc); 253276149Sae if (sc->gif_ecookie == NULL) 254276149Sae return (EEXIST); 255276149Sae return (0); 256105293Sume} 257