ip6_gre.c revision 284066
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: stable/10/sys/netinet6/ip6_gre.c 284066 2015-06-06 12:44:42Z ae $"); 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; 66extern int gre_input(struct mbuf **, int *, int); 67 68int in6_gre_attach(struct gre_softc *); 69int in6_gre_output(struct mbuf *, int, int); 70 71struct ip6protosw in6_gre_protosw = { 72 .pr_type = SOCK_RAW, 73 .pr_domain = &inet6domain, 74 .pr_protocol = IPPROTO_GRE, 75 .pr_flags = PR_ATOMIC|PR_ADDR, 76 .pr_input = gre_input, 77 .pr_output = rip6_output, 78 .pr_ctloutput = rip6_ctloutput, 79 .pr_usrreqs = &rip6_usrreqs 80}; 81 82VNET_DEFINE(int, ip6_gre_hlim) = IPV6_DEFHLIM; 83#define V_ip6_gre_hlim VNET(ip6_gre_hlim) 84 85SYSCTL_DECL(_net_inet6_ip6); 86SYSCTL_INT(_net_inet6_ip6, OID_AUTO, grehlim, CTLFLAG_VNET | CTLFLAG_RW, 87 &VNET_NAME(ip6_gre_hlim), 0, "Default hop limit for encapsulated packets"); 88 89static int 90in6_gre_encapcheck(const struct mbuf *m, int off, int proto, void *arg) 91{ 92 GRE_RLOCK_TRACKER; 93 struct gre_softc *sc; 94 struct ip6_hdr *ip6; 95 96 sc = (struct gre_softc *)arg; 97 if ((GRE2IFP(sc)->if_flags & IFF_UP) == 0) 98 return (0); 99 100 M_ASSERTPKTHDR(m); 101 /* 102 * We expect that payload contains at least IPv4 103 * or IPv6 packet. 104 */ 105 if (m->m_pkthdr.len < sizeof(struct greip6) + 106#ifdef INET 107 sizeof(struct ip)) 108#else 109 sizeof(struct ip6_hdr)) 110#endif 111 return (0); 112 113 GRE_RLOCK(sc); 114 if (sc->gre_family == 0) 115 goto bad; 116 117 KASSERT(sc->gre_family == AF_INET6, 118 ("wrong gre_family: %d", sc->gre_family)); 119 120 ip6 = mtod(m, struct ip6_hdr *); 121 if (!IN6_ARE_ADDR_EQUAL(&sc->gre_oip6.ip6_src, &ip6->ip6_dst) || 122 !IN6_ARE_ADDR_EQUAL(&sc->gre_oip6.ip6_dst, &ip6->ip6_src)) 123 goto bad; 124 125 GRE_RUNLOCK(sc); 126 return (128 * 2); 127bad: 128 GRE_RUNLOCK(sc); 129 return (0); 130} 131 132int 133in6_gre_output(struct mbuf *m, int af, int hlen) 134{ 135 struct greip6 *gi6; 136 137 gi6 = mtod(m, struct greip6 *); 138 gi6->gi6_ip6.ip6_hlim = V_ip6_gre_hlim; 139 return (ip6_output(m, NULL, NULL, IPV6_MINMTU, NULL, NULL, NULL)); 140} 141 142int 143in6_gre_attach(struct gre_softc *sc) 144{ 145 146 KASSERT(sc->gre_ecookie == NULL, ("gre_ecookie isn't NULL")); 147 sc->gre_ecookie = encap_attach_func(AF_INET6, IPPROTO_GRE, 148 in6_gre_encapcheck, (void *)&in6_gre_protosw, sc); 149 if (sc->gre_ecookie == NULL) 150 return (EEXIST); 151 return (0); 152} 153