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 extern int gre_input(struct mbuf **, int *, int); 66 67 int in6_gre_attach(struct gre_softc *); 68 int in6_gre_output(struct mbuf *, int, int); 69 70 struct protosw in6_gre_protosw = { 71 .pr_type = SOCK_RAW, 72 .pr_domain = &inet6domain, 73 .pr_protocol = IPPROTO_GRE, 74 .pr_flags = PR_ATOMIC|PR_ADDR, 75 .pr_input = gre_input, 76 .pr_output = rip6_output, 77 .pr_ctloutput = rip6_ctloutput, 78 .pr_usrreqs = &rip6_usrreqs 79 }; 80 81 VNET_DEFINE(int, ip6_gre_hlim) = IPV6_DEFHLIM; 82 #define V_ip6_gre_hlim VNET(ip6_gre_hlim) 83 84 SYSCTL_DECL(_net_inet6_ip6); 85 SYSCTL_INT(_net_inet6_ip6, OID_AUTO, grehlim, CTLFLAG_VNET | CTLFLAG_RW, 86 &VNET_NAME(ip6_gre_hlim), 0, "Default hop limit for encapsulated packets"); 87 88 static int 89 in6_gre_encapcheck(const struct mbuf *m, int off, int proto, void *arg) 90 { 91 GRE_RLOCK_TRACKER; 92 struct gre_softc *sc; 93 struct ip6_hdr *ip6; 94 95 sc = (struct gre_softc *)arg; 96 if ((GRE2IFP(sc)->if_flags & IFF_UP) == 0) 97 return (0); 98 99 M_ASSERTPKTHDR(m); 100 /* 101 * We expect that payload contains at least IPv4 102 * or IPv6 packet. 103 */ 104 if (m->m_pkthdr.len < sizeof(struct greip6) + 105 #ifdef INET 106 sizeof(struct ip)) 107 #else 108 sizeof(struct ip6_hdr)) 109 #endif 110 return (0); 111 112 GRE_RLOCK(sc); 113 if (sc->gre_family == 0) 114 goto bad; 115 116 KASSERT(sc->gre_family == AF_INET6, 117 ("wrong gre_family: %d", sc->gre_family)); 118 119 ip6 = mtod(m, struct ip6_hdr *); 120 if (!IN6_ARE_ADDR_EQUAL(&sc->gre_oip6.ip6_src, &ip6->ip6_dst) || 121 !IN6_ARE_ADDR_EQUAL(&sc->gre_oip6.ip6_dst, &ip6->ip6_src)) 122 goto bad; 123 124 GRE_RUNLOCK(sc); 125 return (128 * 2); 126 bad: 127 GRE_RUNLOCK(sc); 128 return (0); 129 } 130 131 int 132 in6_gre_output(struct mbuf *m, int af, int hlen) 133 { 134 struct greip6 *gi6; 135 136 gi6 = mtod(m, struct greip6 *); 137 gi6->gi6_ip6.ip6_hlim = V_ip6_gre_hlim; 138 return (ip6_output(m, NULL, NULL, IPV6_MINMTU, NULL, NULL, NULL)); 139 } 140 141 int 142 in6_gre_attach(struct gre_softc *sc) 143 { 144 145 KASSERT(sc->gre_ecookie == NULL, ("gre_ecookie isn't NULL")); 146 sc->gre_ecookie = encap_attach_func(AF_INET6, IPPROTO_GRE, 147 in6_gre_encapcheck, &in6_gre_protosw, sc); 148 if (sc->gre_ecookie == NULL) 149 return (EEXIST); 150 return (0); 151 } 152