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/protosw.h> 46 #include <sys/malloc.h> 47 48 #include <net/if.h> 49 #include <net/if_var.h> 50 #include <net/vnet.h> 51 52 #include <netinet/in.h> 53 #include <netinet/in_systm.h> 54 #ifdef INET 55 #include <net/ethernet.h> 56 #include <netinet/ip.h> 57 #endif 58 #include <netinet/ip_encap.h> 59 #include <netinet/ip6.h> 60 #include <netinet6/ip6_var.h> 61 #include <netinet6/in6_var.h> 62 #include <net/if_gre.h> 63 64 extern struct domain inet6domain; 65 struct protosw in6_gre_protosw = { 66 .pr_type = SOCK_RAW, 67 .pr_domain = &inet6domain, 68 .pr_protocol = IPPROTO_GRE, 69 .pr_flags = PR_ATOMIC|PR_ADDR, 70 .pr_input = gre_input, 71 .pr_output = rip6_output, 72 .pr_ctloutput = rip6_ctloutput, 73 .pr_usrreqs = &rip6_usrreqs 74 }; 75 76 VNET_DEFINE(int, ip6_gre_hlim) = IPV6_DEFHLIM; 77 #define V_ip6_gre_hlim VNET(ip6_gre_hlim) 78 79 SYSCTL_DECL(_net_inet6_ip6); 80 SYSCTL_INT(_net_inet6_ip6, OID_AUTO, grehlim, CTLFLAG_VNET | CTLFLAG_RW, 81 &VNET_NAME(ip6_gre_hlim), 0, "Default hop limit for encapsulated packets"); 82 83 static int 84 in6_gre_encapcheck(const struct mbuf *m, int off, int proto, void *arg) 85 { 86 GRE_RLOCK_TRACKER; 87 struct gre_softc *sc; 88 struct ip6_hdr *ip6; 89 90 sc = (struct gre_softc *)arg; 91 if ((GRE2IFP(sc)->if_flags & IFF_UP) == 0) 92 return (0); 93 94 M_ASSERTPKTHDR(m); 95 /* 96 * We expect that payload contains at least IPv4 97 * or IPv6 packet. 98 */ 99 if (m->m_pkthdr.len < sizeof(struct greip6) + 100 #ifdef INET 101 sizeof(struct ip)) 102 #else 103 sizeof(struct ip6_hdr)) 104 #endif 105 return (0); 106 107 GRE_RLOCK(sc); 108 if (sc->gre_family == 0) 109 goto bad; 110 111 KASSERT(sc->gre_family == AF_INET6, 112 ("wrong gre_family: %d", sc->gre_family)); 113 114 ip6 = mtod(m, struct ip6_hdr *); 115 if (!IN6_ARE_ADDR_EQUAL(&sc->gre_oip6.ip6_src, &ip6->ip6_dst) || 116 !IN6_ARE_ADDR_EQUAL(&sc->gre_oip6.ip6_dst, &ip6->ip6_src)) 117 goto bad; 118 119 GRE_RUNLOCK(sc); 120 return (128 * 2); 121 bad: 122 GRE_RUNLOCK(sc); 123 return (0); 124 } 125 126 int 127 in6_gre_output(struct mbuf *m, int af, int hlen) 128 { 129 struct greip6 *gi6; 130 131 gi6 = mtod(m, struct greip6 *); 132 gi6->gi6_ip6.ip6_hlim = V_ip6_gre_hlim; 133 return (ip6_output(m, NULL, NULL, IPV6_MINMTU, NULL, NULL, NULL)); 134 } 135 136 int 137 in6_gre_attach(struct gre_softc *sc) 138 { 139 140 KASSERT(sc->gre_ecookie == NULL, ("gre_ecookie isn't NULL")); 141 sc->gre_ecookie = encap_attach_func(AF_INET6, IPPROTO_GRE, 142 in6_gre_encapcheck, &in6_gre_protosw, sc); 143 if (sc->gre_ecookie == NULL) 144 return (EEXIST); 145 return (0); 146 } 147