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/ip6protosw.h> 61#include <netinet6/ip6_var.h> 62#include <netinet6/in6_var.h> 63#include <net/if_gre.h> 64 65extern struct domain inet6domain; 66struct ip6protosw in6_gre_protosw = { 67 .pr_type = SOCK_RAW, 68 .pr_domain = &inet6domain, 69 .pr_protocol = IPPROTO_GRE, 70 .pr_flags = PR_ATOMIC|PR_ADDR, 71 .pr_input = gre_input, 72 .pr_output = rip6_output, 73 .pr_ctloutput = rip6_ctloutput, 74 .pr_usrreqs = &rip6_usrreqs 75}; 76 77VNET_DEFINE(int, ip6_gre_hlim) = IPV6_DEFHLIM; 78#define V_ip6_gre_hlim VNET(ip6_gre_hlim) 79 80SYSCTL_DECL(_net_inet6_ip6); 81SYSCTL_INT(_net_inet6_ip6, OID_AUTO, grehlim, CTLFLAG_VNET | CTLFLAG_RW, 82 &VNET_NAME(ip6_gre_hlim), 0, "Default hop limit for encapsulated packets"); 83 84static int 85in6_gre_encapcheck(const struct mbuf *m, int off, int proto, void *arg) 86{ 87 GRE_RLOCK_TRACKER; 88 struct gre_softc *sc; 89 struct ip6_hdr *ip6; 90 91 sc = (struct gre_softc *)arg; 92 if ((GRE2IFP(sc)->if_flags & IFF_UP) == 0) 93 return (0); 94 95 M_ASSERTPKTHDR(m); 96 /* 97 * We expect that payload contains at least IPv4 98 * or IPv6 packet. 99 */ 100 if (m->m_pkthdr.len < sizeof(struct greip6) + 101#ifdef INET 102 sizeof(struct ip)) 103#else 104 sizeof(struct ip6_hdr)) 105#endif 106 return (0); 107 108 GRE_RLOCK(sc); 109 if (sc->gre_family == 0) 110 goto bad; 111 112 KASSERT(sc->gre_family == AF_INET6, 113 ("wrong gre_family: %d", sc->gre_family)); 114 115 ip6 = mtod(m, struct ip6_hdr *); 116 if (!IN6_ARE_ADDR_EQUAL(&sc->gre_oip6.ip6_src, &ip6->ip6_dst) || 117 !IN6_ARE_ADDR_EQUAL(&sc->gre_oip6.ip6_dst, &ip6->ip6_src)) 118 goto bad; 119 120 GRE_RUNLOCK(sc); 121 return (128 * 2); 122bad: 123 GRE_RUNLOCK(sc); 124 return (0); 125} 126 127int 128in6_gre_output(struct mbuf *m, int af, int hlen) 129{ 130 struct greip6 *gi6; 131 132 gi6 = mtod(m, struct greip6 *); 133 gi6->gi6_ip6.ip6_hlim = V_ip6_gre_hlim; 134 return (ip6_output(m, NULL, NULL, IPV6_MINMTU, NULL, NULL, NULL)); 135} 136 137int 138in6_gre_attach(struct gre_softc *sc) 139{ 140 141 KASSERT(sc->gre_ecookie == NULL, ("gre_ecookie isn't NULL")); 142 sc->gre_ecookie = encap_attach_func(AF_INET6, IPPROTO_GRE, 143 in6_gre_encapcheck, (void *)&in6_gre_protosw, sc); 144 if (sc->gre_ecookie == NULL) 145 return (EEXIST); 146 return (0); 147} 148