1 /*- 2 * Copyright (c) 2014 Andrey V. Elsukov <ae@FreeBSD.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 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 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 */ 26 27 #include <sys/cdefs.h> 28 __FBSDID("$FreeBSD$"); 29 30 #include "opt_inet.h" 31 #include "opt_inet6.h" 32 33 #include <sys/param.h> 34 #include <sys/lock.h> 35 #include <sys/rmlock.h> 36 #include <sys/systm.h> 37 #include <sys/socket.h> 38 #include <sys/sockio.h> 39 #include <sys/mbuf.h> 40 #include <sys/errno.h> 41 #include <sys/kernel.h> 42 #include <sys/queue.h> 43 #include <sys/syslog.h> 44 #include <sys/sysctl.h> 45 #include <sys/malloc.h> 46 47 #include <net/if.h> 48 #include <net/if_var.h> 49 #include <net/vnet.h> 50 51 #include <netinet/in.h> 52 #include <netinet/in_systm.h> 53 #ifdef INET 54 #include <net/ethernet.h> 55 #include <netinet/ip.h> 56 #endif 57 #include <netinet/ip_encap.h> 58 #include <netinet/ip6.h> 59 #include <netinet6/ip6_var.h> 60 #include <netinet6/in6_var.h> 61 #include <net/if_gre.h> 62 63 VNET_DEFINE(int, ip6_gre_hlim) = IPV6_DEFHLIM; 64 #define V_ip6_gre_hlim VNET(ip6_gre_hlim) 65 66 SYSCTL_DECL(_net_inet6_ip6); 67 SYSCTL_INT(_net_inet6_ip6, OID_AUTO, grehlim, CTLFLAG_VNET | CTLFLAG_RW, 68 &VNET_NAME(ip6_gre_hlim), 0, "Default hop limit for encapsulated packets"); 69 70 static int 71 in6_gre_encapcheck(const struct mbuf *m, int off, int proto, void *arg) 72 { 73 GRE_RLOCK_TRACKER; 74 struct gre_softc *sc; 75 struct ip6_hdr *ip6; 76 77 sc = (struct gre_softc *)arg; 78 if ((GRE2IFP(sc)->if_flags & IFF_UP) == 0) 79 return (0); 80 81 M_ASSERTPKTHDR(m); 82 83 GRE_RLOCK(sc); 84 if (sc->gre_family == 0) 85 goto bad; 86 87 KASSERT(sc->gre_family == AF_INET6, 88 ("wrong gre_family: %d", sc->gre_family)); 89 90 ip6 = mtod(m, struct ip6_hdr *); 91 if (!IN6_ARE_ADDR_EQUAL(&sc->gre_oip6.ip6_src, &ip6->ip6_dst) || 92 !IN6_ARE_ADDR_EQUAL(&sc->gre_oip6.ip6_dst, &ip6->ip6_src)) 93 goto bad; 94 95 GRE_RUNLOCK(sc); 96 return (128 * 2 + 32); 97 bad: 98 GRE_RUNLOCK(sc); 99 return (0); 100 } 101 102 int 103 in6_gre_output(struct mbuf *m, int af, int hlen) 104 { 105 struct greip6 *gi6; 106 107 gi6 = mtod(m, struct greip6 *); 108 gi6->gi6_ip6.ip6_hlim = V_ip6_gre_hlim; 109 return (ip6_output(m, NULL, NULL, IPV6_MINMTU, NULL, NULL, NULL)); 110 } 111 112 static const struct encap_config ipv6_encap_cfg = { 113 .proto = IPPROTO_GRE, 114 .min_length = sizeof(struct greip6) + 115 #ifdef INET 116 sizeof(struct ip), 117 #else 118 sizeof(struct ip6_hdr), 119 #endif 120 .exact_match = (sizeof(struct in6_addr) << 4) + 32, 121 .check = in6_gre_encapcheck, 122 .input = gre_input 123 }; 124 125 int 126 in6_gre_attach(struct gre_softc *sc) 127 { 128 129 KASSERT(sc->gre_ecookie == NULL, ("gre_ecookie isn't NULL")); 130 sc->gre_ecookie = ip6_encap_attach(&ipv6_encap_cfg, sc, M_WAITOK); 131 return (0); 132 } 133