162587Sitojun/* $FreeBSD: stable/10/sys/net/if_stf.c 340958 2018-11-26 12:19:30Z eugen $ */ 295023Ssuz/* $KAME: if_stf.c,v 1.73 2001/12/03 11:08:30 keiichi Exp $ */ 362587Sitojun 4139823Simp/*- 562587Sitojun * Copyright (C) 2000 WIDE Project. 662587Sitojun * All rights reserved. 762587Sitojun * 862587Sitojun * Redistribution and use in source and binary forms, with or without 962587Sitojun * modification, are permitted provided that the following conditions 1062587Sitojun * are met: 1162587Sitojun * 1. Redistributions of source code must retain the above copyright 1262587Sitojun * notice, this list of conditions and the following disclaimer. 1362587Sitojun * 2. Redistributions in binary form must reproduce the above copyright 1462587Sitojun * notice, this list of conditions and the following disclaimer in the 1562587Sitojun * documentation and/or other materials provided with the distribution. 1662587Sitojun * 3. Neither the name of the project nor the names of its contributors 1762587Sitojun * may be used to endorse or promote products derived from this software 1862587Sitojun * without specific prior written permission. 1962587Sitojun * 2062587Sitojun * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 2162587Sitojun * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 2262587Sitojun * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 2362587Sitojun * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 2462587Sitojun * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 2562587Sitojun * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 2662587Sitojun * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 2762587Sitojun * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 2862587Sitojun * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 2962587Sitojun * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 3062587Sitojun * SUCH DAMAGE. 3162587Sitojun */ 3262587Sitojun 3362587Sitojun/* 3478064Sume * 6to4 interface, based on RFC3056. 3562587Sitojun * 3662587Sitojun * 6to4 interface is NOT capable of link-layer (I mean, IPv4) multicasting. 3762587Sitojun * There is no address mapping defined from IPv6 multicast address to IPv4 3862587Sitojun * address. Therefore, we do not have IFF_MULTICAST on the interface. 3962587Sitojun * 4062587Sitojun * Due to the lack of address mapping for link-local addresses, we cannot 4162587Sitojun * throw packets toward link-local addresses (fe80::x). Also, we cannot throw 4262587Sitojun * packets to link-local multicast addresses (ff02::x). 4362587Sitojun * 4462587Sitojun * Here are interesting symptoms due to the lack of link-local address: 4562587Sitojun * 4662587Sitojun * Unicast routing exchange: 4762587Sitojun * - RIPng: Impossible. Uses link-local multicast packet toward ff02::9, 4862587Sitojun * and link-local addresses as nexthop. 4962587Sitojun * - OSPFv6: Impossible. OSPFv6 assumes that there's link-local address 5062587Sitojun * assigned to the link, and makes use of them. Also, HELLO packets use 5162587Sitojun * link-local multicast addresses (ff02::5 and ff02::6). 5262587Sitojun * - BGP4+: Maybe. You can only use global address as nexthop, and global 5362587Sitojun * address as TCP endpoint address. 5462587Sitojun * 5562587Sitojun * Multicast routing protocols: 5662587Sitojun * - PIM: Hello packet cannot be used to discover adjacent PIM routers. 5762587Sitojun * Adjacent PIM routers must be configured manually (is it really spec-wise 5862587Sitojun * correct thing to do?). 5962587Sitojun * 6062587Sitojun * ICMPv6: 6162587Sitojun * - Redirects cannot be used due to the lack of link-local address. 6262587Sitojun * 6378064Sume * stf interface does not have, and will not need, a link-local address. 6478064Sume * It seems to have no real benefit and does not help the above symptoms much. 6578064Sume * Even if we assign link-locals to interface, we cannot really 6678064Sume * use link-local unicast/multicast on top of 6to4 cloud (since there's no 6778064Sume * encapsulation defined for link-local address), and the above analysis does 6878064Sume * not change. RFC3056 does not mandate the assignment of link-local address 6978064Sume * either. 7062587Sitojun * 7162587Sitojun * 6to4 interface has security issues. Refer to 7262587Sitojun * http://playground.iijlab.net/i-d/draft-itojun-ipv6-transition-abuse-00.txt 7362587Sitojun * for details. The code tries to filter out some of malicious packets. 7462587Sitojun * Note that there is no way to be 100% secure. 7562587Sitojun */ 7662587Sitojun 7762587Sitojun#include "opt_inet.h" 7862587Sitojun#include "opt_inet6.h" 7962587Sitojun 8062587Sitojun#include <sys/param.h> 8162587Sitojun#include <sys/systm.h> 8262587Sitojun#include <sys/socket.h> 8362587Sitojun#include <sys/sockio.h> 8462587Sitojun#include <sys/mbuf.h> 8562587Sitojun#include <sys/errno.h> 8683655Sbrooks#include <sys/kernel.h> 87129880Sphk#include <sys/module.h> 8862587Sitojun#include <sys/protosw.h> 89178888Sjulian#include <sys/proc.h> 9083655Sbrooks#include <sys/queue.h> 91183351Sdwmalone#include <sys/sysctl.h> 9262587Sitojun#include <machine/cpu.h> 9362587Sitojun 9462587Sitojun#include <sys/malloc.h> 9562587Sitojun 9662587Sitojun#include <net/if.h> 97130933Sbrooks#include <net/if_clone.h> 9862587Sitojun#include <net/route.h> 9962587Sitojun#include <net/netisr.h> 10062587Sitojun#include <net/if_types.h> 10162587Sitojun#include <net/if_stf.h> 102196019Srwatson#include <net/vnet.h> 10362587Sitojun 10462587Sitojun#include <netinet/in.h> 10562587Sitojun#include <netinet/in_systm.h> 10662587Sitojun#include <netinet/ip.h> 10762587Sitojun#include <netinet/ip_var.h> 10862587Sitojun#include <netinet/in_var.h> 10962587Sitojun 11062587Sitojun#include <netinet/ip6.h> 11162587Sitojun#include <netinet6/ip6_var.h> 11262587Sitojun#include <netinet6/in6_var.h> 11362587Sitojun#include <netinet/ip_ecn.h> 11462587Sitojun 11562587Sitojun#include <netinet/ip_encap.h> 11662587Sitojun 11762587Sitojun#include <machine/stdarg.h> 11862587Sitojun 11962587Sitojun#include <net/bpf.h> 12062587Sitojun 121163606Srwatson#include <security/mac/mac_framework.h> 122163606Srwatson 123183351SdwmaloneSYSCTL_DECL(_net_link); 124227309Sedstatic SYSCTL_NODE(_net_link, IFT_STF, stf, CTLFLAG_RW, 0, "6to4 Interface"); 125183351Sdwmalone 126183351Sdwmalonestatic int stf_route_cache = 1; 127183351SdwmaloneSYSCTL_INT(_net_link_stf, OID_AUTO, route_cache, CTLFLAG_RW, 128183351Sdwmalone &stf_route_cache, 0, "Caching of IPv4 routes for 6to4 Output"); 129183351Sdwmalone 130244750Saestatic int stf_permit_rfc1918 = 0; 131244752SaeTUNABLE_INT("net.link.stf.permit_rfc1918", &stf_permit_rfc1918); 132244752SaeSYSCTL_INT(_net_link_stf, OID_AUTO, permit_rfc1918, CTLFLAG_RW | CTLFLAG_TUN, 133244750Sae &stf_permit_rfc1918, 0, "Permit the use of private IPv4 addresses"); 134244750Sae 135130933Sbrooks#define STFUNIT 0 13683655Sbrooks 13762587Sitojun#define IN6_IS_ADDR_6TO4(x) (ntohs((x)->s6_addr16[0]) == 0x2002) 13862587Sitojun 139109322Ssuz/* 140109322Ssuz * XXX: Return a pointer with 16-bit aligned. Don't cast it to 141109322Ssuz * struct in_addr *; use bcopy() instead. 142109322Ssuz */ 143249925Sglebius#define GET_V4(x) (&(x)->s6_addr16[1]) 144109322Ssuz 14562587Sitojunstruct stf_softc { 146147256Sbrooks struct ifnet *sc_ifp; 14762587Sitojun union { 14862587Sitojun struct route __sc_ro4; 14962587Sitojun struct route_in6 __sc_ro6; /* just for safety */ 15062587Sitojun } __sc_ro46; 15162587Sitojun#define sc_ro __sc_ro46.__sc_ro4 152183351Sdwmalone struct mtx sc_ro_mtx; 153178888Sjulian u_int sc_fibnum; 15462587Sitojun const struct encaptab *encap_cookie; 15562587Sitojun}; 156147256Sbrooks#define STF2IFP(sc) ((sc)->sc_ifp) 15762587Sitojun 158241610Sglebiusstatic const char stfname[] = "stf"; 159241610Sglebius 160126783Srwatson/* 161183351Sdwmalone * Note that mutable fields in the softc are not currently locked. 162183351Sdwmalone * We do lock sc_ro in stf_output though. 163126783Srwatson */ 164241610Sglebiusstatic MALLOC_DEFINE(M_STF, stfname, "6to4 Tunnel Interface"); 165126709Srwatsonstatic const int ip_stf_ttl = 40; 16662587Sitojun 16779106Sbrooksextern struct domain inetdomain; 168152242Srustruct protosw in_stf_protosw = { 169152242Sru .pr_type = SOCK_RAW, 170152242Sru .pr_domain = &inetdomain, 171152242Sru .pr_protocol = IPPROTO_IPV6, 172152242Sru .pr_flags = PR_ATOMIC|PR_ADDR, 173152242Sru .pr_input = in_stf_input, 174152242Sru .pr_output = (pr_output_t *)rip_output, 175152242Sru .pr_ctloutput = rip_ctloutput, 176152242Sru .pr_usrreqs = &rip_usrreqs 17779106Sbrooks}; 17862587Sitojun 179130933Sbrooksstatic char *stfnames[] = {"stf0", "stf", "6to4", NULL}; 180130933Sbrooks 18192725Salfredstatic int stfmodevent(module_t, int, void *); 18292725Salfredstatic int stf_encapcheck(const struct mbuf *, int, int, void *); 18392725Salfredstatic struct in6_ifaddr *stf_getsrcifa6(struct ifnet *); 184249925Sglebiusstatic int stf_output(struct ifnet *, struct mbuf *, const struct sockaddr *, 185191148Skmacy struct route *); 186103475Sumestatic int isrfc1918addr(struct in_addr *); 18792725Salfredstatic int stf_checkaddr4(struct stf_softc *, struct in_addr *, 18892725Salfred struct ifnet *); 18992725Salfredstatic int stf_checkaddr6(struct stf_softc *, struct in6_addr *, 19092725Salfred struct ifnet *); 19192725Salfredstatic void stf_rtrequest(int, struct rtentry *, struct rt_addrinfo *); 19292725Salfredstatic int stf_ioctl(struct ifnet *, u_long, caddr_t); 19362587Sitojun 194130933Sbrooksstatic int stf_clone_match(struct if_clone *, const char *); 195160195Ssamstatic int stf_clone_create(struct if_clone *, char *, size_t, caddr_t); 196130933Sbrooksstatic int stf_clone_destroy(struct if_clone *, struct ifnet *); 197241610Sglebiusstatic struct if_clone *stf_cloner; 19883655Sbrooks 199130933Sbrooksstatic int 200130933Sbrooksstf_clone_match(struct if_clone *ifc, const char *name) 201130933Sbrooks{ 202130933Sbrooks int i; 20383655Sbrooks 204130933Sbrooks for(i = 0; stfnames[i] != NULL; i++) { 205130933Sbrooks if (strcmp(stfnames[i], name) == 0) 206130933Sbrooks return (1); 207130933Sbrooks } 208130933Sbrooks 209130933Sbrooks return (0); 210130933Sbrooks} 211130933Sbrooks 212128209Sbrooksstatic int 213160195Ssamstf_clone_create(struct if_clone *ifc, char *name, size_t len, caddr_t params) 21483655Sbrooks{ 215130933Sbrooks int err, unit; 21683655Sbrooks struct stf_softc *sc; 217128417Sbrooks struct ifnet *ifp; 21883655Sbrooks 219130933Sbrooks /* 220130933Sbrooks * We can only have one unit, but since unit allocation is 221130933Sbrooks * already locked, we use it to keep from allocating extra 222130933Sbrooks * interfaces. 223130933Sbrooks */ 224130933Sbrooks unit = STFUNIT; 225130933Sbrooks err = ifc_alloc_unit(ifc, &unit); 226130933Sbrooks if (err != 0) 227130933Sbrooks return (err); 228130933Sbrooks 229111119Simp sc = malloc(sizeof(struct stf_softc), M_STF, M_WAITOK | M_ZERO); 230147346Sbrooks ifp = STF2IFP(sc) = if_alloc(IFT_STF); 231147256Sbrooks if (ifp == NULL) { 232147256Sbrooks free(sc, M_STF); 233147256Sbrooks ifc_free_unit(ifc, unit); 234147256Sbrooks return (ENOSPC); 235147256Sbrooks } 236147346Sbrooks ifp->if_softc = sc; 237178888Sjulian sc->sc_fibnum = curthread->td_proc->p_fibnum; 238147346Sbrooks 239130933Sbrooks /* 240130933Sbrooks * Set the name manually rather then using if_initname because 241130933Sbrooks * we don't conform to the default naming convention for interfaces. 242130933Sbrooks */ 243130933Sbrooks strlcpy(ifp->if_xname, name, IFNAMSIZ); 244241610Sglebius ifp->if_dname = stfname; 245130933Sbrooks ifp->if_dunit = IF_DUNIT_NONE; 24683655Sbrooks 247183351Sdwmalone mtx_init(&(sc)->sc_ro_mtx, "stf ro", NULL, MTX_DEF); 24883655Sbrooks sc->encap_cookie = encap_attach_func(AF_INET, IPPROTO_IPV6, 24983655Sbrooks stf_encapcheck, &in_stf_protosw, sc); 25083655Sbrooks if (sc->encap_cookie == NULL) { 251128417Sbrooks if_printf(ifp, "attach failed\n"); 25283655Sbrooks free(sc, M_STF); 253130933Sbrooks ifc_free_unit(ifc, unit); 25483655Sbrooks return (ENOMEM); 25583655Sbrooks } 25683655Sbrooks 257128417Sbrooks ifp->if_mtu = IPV6_MMTU; 258128417Sbrooks ifp->if_ioctl = stf_ioctl; 259128417Sbrooks ifp->if_output = stf_output; 260207554Ssobomax ifp->if_snd.ifq_maxlen = ifqmaxlen; 261128417Sbrooks if_attach(ifp); 262147611Sdwmalone bpfattach(ifp, DLT_NULL, sizeof(u_int32_t)); 26383655Sbrooks return (0); 26483655Sbrooks} 26583655Sbrooks 266130933Sbrooksstatic int 267130933Sbrooksstf_clone_destroy(struct if_clone *ifc, struct ifnet *ifp) 26883655Sbrooks{ 269147256Sbrooks struct stf_softc *sc = ifp->if_softc; 270151266Sthompsa int err; 27183655Sbrooks 272151266Sthompsa err = encap_detach(sc->encap_cookie); 273151266Sthompsa KASSERT(err == 0, ("Unexpected error detaching encap_cookie")); 274183351Sdwmalone mtx_destroy(&(sc)->sc_ro_mtx); 275151266Sthompsa bpfdetach(ifp); 276151266Sthompsa if_detach(ifp); 277151266Sthompsa if_free(ifp); 278151266Sthompsa 279151266Sthompsa free(sc, M_STF); 280130933Sbrooks ifc_free_unit(ifc, STFUNIT); 281130933Sbrooks 282130933Sbrooks return (0); 28383655Sbrooks} 28483655Sbrooks 28579106Sbrooksstatic int 28679106Sbrooksstfmodevent(mod, type, data) 28779106Sbrooks module_t mod; 28879106Sbrooks int type; 28979106Sbrooks void *data; 29062587Sitojun{ 29162587Sitojun 29279106Sbrooks switch (type) { 29379106Sbrooks case MOD_LOAD: 294241610Sglebius stf_cloner = if_clone_advanced(stfname, 0, stf_clone_match, 295241610Sglebius stf_clone_create, stf_clone_destroy); 29679106Sbrooks break; 29779106Sbrooks case MOD_UNLOAD: 298241610Sglebius if_clone_detach(stf_cloner); 29979106Sbrooks break; 300132199Sphk default: 301132199Sphk return (EOPNOTSUPP); 30262587Sitojun } 30379106Sbrooks 30479106Sbrooks return (0); 30562587Sitojun} 30662587Sitojun 30779106Sbrooksstatic moduledata_t stf_mod = { 30879106Sbrooks "if_stf", 30979106Sbrooks stfmodevent, 310241394Skevlo 0 31179106Sbrooks}; 31262587Sitojun 31379106SbrooksDECLARE_MODULE(if_stf, stf_mod, SI_SUB_PSEUDO, SI_ORDER_ANY); 31479106Sbrooks 31562587Sitojunstatic int 31662587Sitojunstf_encapcheck(m, off, proto, arg) 31762587Sitojun const struct mbuf *m; 31862587Sitojun int off; 31962587Sitojun int proto; 32062587Sitojun void *arg; 32162587Sitojun{ 32262587Sitojun struct ip ip; 32362587Sitojun struct in6_ifaddr *ia6; 32462587Sitojun struct stf_softc *sc; 325108710Sfenner struct in_addr a, b, mask; 32662587Sitojun 32762587Sitojun sc = (struct stf_softc *)arg; 32862587Sitojun if (sc == NULL) 32962587Sitojun return 0; 33062587Sitojun 331147256Sbrooks if ((STF2IFP(sc)->if_flags & IFF_UP) == 0) 33262587Sitojun return 0; 33362587Sitojun 33478064Sume /* IFF_LINK0 means "no decapsulation" */ 335147256Sbrooks if ((STF2IFP(sc)->if_flags & IFF_LINK0) != 0) 33678064Sume return 0; 33778064Sume 33862587Sitojun if (proto != IPPROTO_IPV6) 33962587Sitojun return 0; 34062587Sitojun 34162587Sitojun /* LINTED const cast */ 34291452Speter m_copydata((struct mbuf *)(uintptr_t)m, 0, sizeof(ip), (caddr_t)&ip); 34362587Sitojun 34462587Sitojun if (ip.ip_v != 4) 34562587Sitojun return 0; 34662587Sitojun 347147256Sbrooks ia6 = stf_getsrcifa6(STF2IFP(sc)); 34862587Sitojun if (ia6 == NULL) 34962587Sitojun return 0; 35062587Sitojun 35162587Sitojun /* 35262587Sitojun * check if IPv4 dst matches the IPv4 address derived from the 35362587Sitojun * local 6to4 address. 35462587Sitojun * success on: dst = 10.1.1.1, ia6->ia_addr = 2002:0a01:0101:... 35562587Sitojun */ 35662587Sitojun if (bcmp(GET_V4(&ia6->ia_addr.sin6_addr), &ip.ip_dst, 357194812Srwatson sizeof(ip.ip_dst)) != 0) { 358194812Srwatson ifa_free(&ia6->ia_ifa); 35962587Sitojun return 0; 360194812Srwatson } 36162587Sitojun 36262587Sitojun /* 36362587Sitojun * check if IPv4 src matches the IPv4 address derived from the 36462587Sitojun * local 6to4 address masked by prefixmask. 36562587Sitojun * success on: src = 10.1.1.1, ia6->ia_addr = 2002:0a00:.../24 36662587Sitojun * fail on: src = 10.1.1.1, ia6->ia_addr = 2002:0b00:.../24 36762587Sitojun */ 36862587Sitojun bzero(&a, sizeof(a)); 369108710Sfenner bcopy(GET_V4(&ia6->ia_addr.sin6_addr), &a, sizeof(a)); 370108710Sfenner bcopy(GET_V4(&ia6->ia_prefixmask.sin6_addr), &mask, sizeof(mask)); 371194812Srwatson ifa_free(&ia6->ia_ifa); 372108710Sfenner a.s_addr &= mask.s_addr; 37362587Sitojun b = ip.ip_src; 374108710Sfenner b.s_addr &= mask.s_addr; 37562587Sitojun if (a.s_addr != b.s_addr) 37662587Sitojun return 0; 37762587Sitojun 37862587Sitojun /* stf interface makes single side match only */ 37962587Sitojun return 32; 38062587Sitojun} 38162587Sitojun 38262587Sitojunstatic struct in6_ifaddr * 38362587Sitojunstf_getsrcifa6(ifp) 38462587Sitojun struct ifnet *ifp; 38562587Sitojun{ 38662587Sitojun struct ifaddr *ia; 38762587Sitojun struct sockaddr_in6 *sin6; 38862587Sitojun struct in_addr in; 38962587Sitojun 390195022Srwatson if_addr_rlock(ifp); 391191339Srwatson TAILQ_FOREACH(ia, &ifp->if_addrhead, ifa_link) { 39262587Sitojun if (ia->ifa_addr->sa_family != AF_INET6) 39362587Sitojun continue; 39462587Sitojun sin6 = (struct sockaddr_in6 *)ia->ifa_addr; 39562587Sitojun if (!IN6_IS_ADDR_6TO4(&sin6->sin6_addr)) 39662587Sitojun continue; 39762587Sitojun 39862587Sitojun bcopy(GET_V4(&sin6->sin6_addr), &in, sizeof(in)); 399340958Seugen if (!in_localip(in)) 40062587Sitojun continue; 40162587Sitojun 402194812Srwatson ifa_ref(ia); 403195022Srwatson if_addr_runlock(ifp); 40462587Sitojun return (struct in6_ifaddr *)ia; 40562587Sitojun } 406195022Srwatson if_addr_runlock(ifp); 40762587Sitojun 40862587Sitojun return NULL; 40962587Sitojun} 41062587Sitojun 41162587Sitojunstatic int 412249925Sglebiusstf_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst, 413249925Sglebius struct route *ro) 41462587Sitojun{ 41562587Sitojun struct stf_softc *sc; 416249925Sglebius const struct sockaddr_in6 *dst6; 417183351Sdwmalone struct route *cached_route; 418109322Ssuz struct in_addr in4; 419249925Sglebius const void *ptr; 42062587Sitojun struct sockaddr_in *dst4; 42162587Sitojun u_int8_t tos; 42262587Sitojun struct ip *ip; 42362587Sitojun struct ip6_hdr *ip6; 42462587Sitojun struct in6_ifaddr *ia6; 425105580Srwatson int error; 42662587Sitojun 427183351Sdwmalone#ifdef MAC 428172930Srwatson error = mac_ifnet_check_transmit(ifp, m); 429105580Srwatson if (error) { 430105580Srwatson m_freem(m); 431105580Srwatson return (error); 432105580Srwatson } 433105580Srwatson#endif 434105580Srwatson 435147256Sbrooks sc = ifp->if_softc; 436249925Sglebius dst6 = (const struct sockaddr_in6 *)dst; 43762587Sitojun 43862587Sitojun /* just in case */ 43962587Sitojun if ((ifp->if_flags & IFF_UP) == 0) { 44062587Sitojun m_freem(m); 441103487Sume ifp->if_oerrors++; 44262587Sitojun return ENETDOWN; 44362587Sitojun } 44462587Sitojun 44562587Sitojun /* 44662587Sitojun * If we don't have an ip4 address that match my inner ip6 address, 44762587Sitojun * we shouldn't generate output. Without this check, we'll end up 44862587Sitojun * using wrong IPv4 source. 44962587Sitojun */ 45062587Sitojun ia6 = stf_getsrcifa6(ifp); 45162587Sitojun if (ia6 == NULL) { 45262587Sitojun m_freem(m); 453103487Sume ifp->if_oerrors++; 45462587Sitojun return ENETDOWN; 45562587Sitojun } 45662587Sitojun 45762587Sitojun if (m->m_len < sizeof(*ip6)) { 45862587Sitojun m = m_pullup(m, sizeof(*ip6)); 459103487Sume if (!m) { 460194812Srwatson ifa_free(&ia6->ia_ifa); 461103487Sume ifp->if_oerrors++; 46262587Sitojun return ENOBUFS; 463103487Sume } 46462587Sitojun } 46562587Sitojun ip6 = mtod(m, struct ip6_hdr *); 46662587Sitojun tos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 46762587Sitojun 46878064Sume /* 46978064Sume * Pickup the right outer dst addr from the list of candidates. 47078064Sume * ip6_dst has priority as it may be able to give us shorter IPv4 hops. 47178064Sume */ 472109322Ssuz ptr = NULL; 47378064Sume if (IN6_IS_ADDR_6TO4(&ip6->ip6_dst)) 474109322Ssuz ptr = GET_V4(&ip6->ip6_dst); 47578064Sume else if (IN6_IS_ADDR_6TO4(&dst6->sin6_addr)) 476109322Ssuz ptr = GET_V4(&dst6->sin6_addr); 47778064Sume else { 478194812Srwatson ifa_free(&ia6->ia_ifa); 47978064Sume m_freem(m); 480103487Sume ifp->if_oerrors++; 48178064Sume return ENETUNREACH; 48278064Sume } 483109322Ssuz bcopy(ptr, &in4, sizeof(in4)); 48478064Sume 485159180Scsjp if (bpf_peers_present(ifp->if_bpf)) { 48678701Sume /* 48778701Sume * We need to prepend the address family as 48878701Sume * a four byte field. Cons up a dummy header 48978701Sume * to pacify bpf. This is safe because bpf 49078701Sume * will only read from the mbuf (i.e., it won't 49178701Sume * try to free it or keep a pointer a to it). 49278701Sume */ 493249925Sglebius u_int af = AF_INET6; 494123922Ssam bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m); 49578701Sume } 49678701Sume 497243882Sglebius M_PREPEND(m, sizeof(struct ip), M_NOWAIT); 498103487Sume if (m == NULL) { 499194812Srwatson ifa_free(&ia6->ia_ifa); 500103487Sume ifp->if_oerrors++; 50162587Sitojun return ENOBUFS; 502103487Sume } 50362587Sitojun ip = mtod(m, struct ip *); 50462587Sitojun 50562587Sitojun bzero(ip, sizeof(*ip)); 50662587Sitojun 50762587Sitojun bcopy(GET_V4(&((struct sockaddr_in6 *)&ia6->ia_addr)->sin6_addr), 50862587Sitojun &ip->ip_src, sizeof(ip->ip_src)); 509194812Srwatson ifa_free(&ia6->ia_ifa); 510109322Ssuz bcopy(&in4, &ip->ip_dst, sizeof(ip->ip_dst)); 51162587Sitojun ip->ip_p = IPPROTO_IPV6; 51279106Sbrooks ip->ip_ttl = ip_stf_ttl; 513241913Sglebius ip->ip_len = htons(m->m_pkthdr.len); 51462587Sitojun if (ifp->if_flags & IFF_LINK1) 51562587Sitojun ip_ecn_ingress(ECN_ALLOWED, &ip->ip_tos, &tos); 51678064Sume else 51778064Sume ip_ecn_ingress(ECN_NOCARE, &ip->ip_tos, &tos); 51862587Sitojun 519183351Sdwmalone if (!stf_route_cache) { 520183351Sdwmalone cached_route = NULL; 521183351Sdwmalone goto sendit; 522183351Sdwmalone } 523183351Sdwmalone 524126783Srwatson /* 525183351Sdwmalone * Do we have a cached route? 526126783Srwatson */ 527183351Sdwmalone mtx_lock(&(sc)->sc_ro_mtx); 52862587Sitojun dst4 = (struct sockaddr_in *)&sc->sc_ro.ro_dst; 52962587Sitojun if (dst4->sin_family != AF_INET || 53062587Sitojun bcmp(&dst4->sin_addr, &ip->ip_dst, sizeof(ip->ip_dst)) != 0) { 53162587Sitojun /* cache route doesn't match */ 53262587Sitojun dst4->sin_family = AF_INET; 53362587Sitojun dst4->sin_len = sizeof(struct sockaddr_in); 53462587Sitojun bcopy(&ip->ip_dst, &dst4->sin_addr, sizeof(dst4->sin_addr)); 53562587Sitojun if (sc->sc_ro.ro_rt) { 53662587Sitojun RTFREE(sc->sc_ro.ro_rt); 53762587Sitojun sc->sc_ro.ro_rt = NULL; 53862587Sitojun } 53962587Sitojun } 54062587Sitojun 54162587Sitojun if (sc->sc_ro.ro_rt == NULL) { 542178888Sjulian rtalloc_fib(&sc->sc_ro, sc->sc_fibnum); 54362587Sitojun if (sc->sc_ro.ro_rt == NULL) { 54462587Sitojun m_freem(m); 545183351Sdwmalone mtx_unlock(&(sc)->sc_ro_mtx); 546103487Sume ifp->if_oerrors++; 54762587Sitojun return ENETUNREACH; 54862587Sitojun } 54962587Sitojun } 550183351Sdwmalone cached_route = &sc->sc_ro; 55162587Sitojun 552183351Sdwmalonesendit: 553178888Sjulian M_SETFIB(m, sc->sc_fibnum); 554103487Sume ifp->if_opackets++; 555183351Sdwmalone error = ip_output(m, NULL, cached_route, 0, NULL, NULL); 556183351Sdwmalone 557183351Sdwmalone if (cached_route != NULL) 558183351Sdwmalone mtx_unlock(&(sc)->sc_ro_mtx); 559183351Sdwmalone return error; 56062587Sitojun} 56162587Sitojun 56262587Sitojunstatic int 563103475Sumeisrfc1918addr(in) 564109322Ssuz struct in_addr *in; 565103475Sume{ 566103475Sume /* 567103475Sume * returns 1 if private address range: 568103475Sume * 10.0.0.0/8 172.16.0.0/12 192.168.0.0/16 569103475Sume */ 570244750Sae if (stf_permit_rfc1918 == 0 && ( 571244750Sae (ntohl(in->s_addr) & 0xff000000) >> 24 == 10 || 572109322Ssuz (ntohl(in->s_addr) & 0xfff00000) >> 16 == 172 * 256 + 16 || 573244750Sae (ntohl(in->s_addr) & 0xffff0000) >> 16 == 192 * 256 + 168)) 574103475Sume return 1; 575103475Sume 576103475Sume return 0; 577103475Sume} 578103475Sume 579103475Sumestatic int 58078064Sumestf_checkaddr4(sc, in, inifp) 58178064Sume struct stf_softc *sc; 582109322Ssuz struct in_addr *in; 58378064Sume struct ifnet *inifp; /* incoming interface */ 58462587Sitojun{ 58562587Sitojun struct in_ifaddr *ia4; 58662587Sitojun 58762587Sitojun /* 58862587Sitojun * reject packets with the following address: 58962587Sitojun * 224.0.0.0/4 0.0.0.0/8 127.0.0.0/8 255.0.0.0/8 59062587Sitojun */ 591109322Ssuz if (IN_MULTICAST(ntohl(in->s_addr))) 59262587Sitojun return -1; 593109322Ssuz switch ((ntohl(in->s_addr) & 0xff000000) >> 24) { 594109322Ssuz case 0: case 127: case 255: 59562587Sitojun return -1; 596109322Ssuz } 59762587Sitojun 59862587Sitojun /* 599103475Sume * reject packets with private address range. 600103475Sume * (requirement from RFC3056 section 2 1st paragraph) 601103475Sume */ 602103475Sume if (isrfc1918addr(in)) 603103475Sume return -1; 604103475Sume 605103475Sume /* 60662587Sitojun * reject packets with broadcast 60762587Sitojun */ 608194951Srwatson IN_IFADDR_RLOCK(); 609239357Sjhb TAILQ_FOREACH(ia4, &V_in_ifaddrhead, ia_link) { 61062587Sitojun if ((ia4->ia_ifa.ifa_ifp->if_flags & IFF_BROADCAST) == 0) 61162587Sitojun continue; 612194951Srwatson if (in->s_addr == ia4->ia_broadaddr.sin_addr.s_addr) { 613194951Srwatson IN_IFADDR_RUNLOCK(); 61462587Sitojun return -1; 615194951Srwatson } 61662587Sitojun } 617194951Srwatson IN_IFADDR_RUNLOCK(); 61862587Sitojun 61962587Sitojun /* 62062587Sitojun * perform ingress filter 62162587Sitojun */ 622147256Sbrooks if (sc && (STF2IFP(sc)->if_flags & IFF_LINK2) == 0 && inifp) { 62362587Sitojun struct sockaddr_in sin; 62462587Sitojun struct rtentry *rt; 62562587Sitojun 62662587Sitojun bzero(&sin, sizeof(sin)); 62762587Sitojun sin.sin_family = AF_INET; 62862587Sitojun sin.sin_len = sizeof(struct sockaddr_in); 629109322Ssuz sin.sin_addr = *in; 630178888Sjulian rt = rtalloc1_fib((struct sockaddr *)&sin, 0, 631178888Sjulian 0UL, sc->sc_fibnum); 63278064Sume if (!rt || rt->rt_ifp != inifp) { 63378064Sume#if 0 63478064Sume log(LOG_WARNING, "%s: packet from 0x%x dropped " 635147256Sbrooks "due to ingress filter\n", if_name(STF2IFP(sc)), 63678064Sume (u_int32_t)ntohl(sin.sin_addr.s_addr)); 63778064Sume#endif 63878064Sume if (rt) 639172307Scsjp RTFREE_LOCKED(rt); 64062587Sitojun return -1; 64162587Sitojun } 642172307Scsjp RTFREE_LOCKED(rt); 64362587Sitojun } 64462587Sitojun 64562587Sitojun return 0; 64662587Sitojun} 64762587Sitojun 64862587Sitojunstatic int 64978064Sumestf_checkaddr6(sc, in6, inifp) 65078064Sume struct stf_softc *sc; 65162587Sitojun struct in6_addr *in6; 65278064Sume struct ifnet *inifp; /* incoming interface */ 65362587Sitojun{ 65462587Sitojun /* 65562587Sitojun * check 6to4 addresses 65662587Sitojun */ 657109322Ssuz if (IN6_IS_ADDR_6TO4(in6)) { 658109322Ssuz struct in_addr in4; 659109322Ssuz bcopy(GET_V4(in6), &in4, sizeof(in4)); 660109322Ssuz return stf_checkaddr4(sc, &in4, inifp); 661109322Ssuz } 66262587Sitojun 66362587Sitojun /* 66462587Sitojun * reject anything that look suspicious. the test is implemented 66562587Sitojun * in ip6_input too, but we check here as well to 66662587Sitojun * (1) reject bad packets earlier, and 66762587Sitojun * (2) to be safe against future ip6_input change. 66862587Sitojun */ 66962587Sitojun if (IN6_IS_ADDR_V4COMPAT(in6) || IN6_IS_ADDR_V4MAPPED(in6)) 67062587Sitojun return -1; 67162587Sitojun 67262587Sitojun return 0; 67362587Sitojun} 67462587Sitojun 67562587Sitojunvoid 67683187Sjulianin_stf_input(m, off) 67778064Sume struct mbuf *m; 67883187Sjulian int off; 67962587Sitojun{ 68083187Sjulian int proto; 68162587Sitojun struct stf_softc *sc; 68262587Sitojun struct ip *ip; 68362587Sitojun struct ip6_hdr *ip6; 68462587Sitojun u_int8_t otos, itos; 68562587Sitojun struct ifnet *ifp; 68662587Sitojun 68782884Sjulian proto = mtod(m, struct ip *)->ip_p; 68862587Sitojun 68962587Sitojun if (proto != IPPROTO_IPV6) { 69062587Sitojun m_freem(m); 69162587Sitojun return; 69262587Sitojun } 69362587Sitojun 69462587Sitojun ip = mtod(m, struct ip *); 69562587Sitojun 69662587Sitojun sc = (struct stf_softc *)encap_getarg(m); 69762587Sitojun 698147256Sbrooks if (sc == NULL || (STF2IFP(sc)->if_flags & IFF_UP) == 0) { 69962587Sitojun m_freem(m); 70062587Sitojun return; 70162587Sitojun } 70262587Sitojun 703147256Sbrooks ifp = STF2IFP(sc); 70462587Sitojun 705105580Srwatson#ifdef MAC 706172930Srwatson mac_ifnet_create_mbuf(ifp, m); 707105580Srwatson#endif 708105580Srwatson 70962587Sitojun /* 71062587Sitojun * perform sanity check against outer src/dst. 71162587Sitojun * for source, perform ingress filter as well. 71262587Sitojun */ 71378064Sume if (stf_checkaddr4(sc, &ip->ip_dst, NULL) < 0 || 71478064Sume stf_checkaddr4(sc, &ip->ip_src, m->m_pkthdr.rcvif) < 0) { 71562587Sitojun m_freem(m); 71662587Sitojun return; 71762587Sitojun } 71862587Sitojun 71962587Sitojun otos = ip->ip_tos; 72062587Sitojun m_adj(m, off); 72162587Sitojun 72262587Sitojun if (m->m_len < sizeof(*ip6)) { 72362587Sitojun m = m_pullup(m, sizeof(*ip6)); 72462587Sitojun if (!m) 72562587Sitojun return; 72662587Sitojun } 72762587Sitojun ip6 = mtod(m, struct ip6_hdr *); 72862587Sitojun 72962587Sitojun /* 73062587Sitojun * perform sanity check against inner src/dst. 73162587Sitojun * for source, perform ingress filter as well. 73262587Sitojun */ 73378064Sume if (stf_checkaddr6(sc, &ip6->ip6_dst, NULL) < 0 || 73478064Sume stf_checkaddr6(sc, &ip6->ip6_src, m->m_pkthdr.rcvif) < 0) { 73562587Sitojun m_freem(m); 73662587Sitojun return; 73762587Sitojun } 73862587Sitojun 73962587Sitojun itos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 74062587Sitojun if ((ifp->if_flags & IFF_LINK1) != 0) 74162587Sitojun ip_ecn_egress(ECN_ALLOWED, &otos, &itos); 74278064Sume else 74378064Sume ip_ecn_egress(ECN_NOCARE, &otos, &itos); 74462587Sitojun ip6->ip6_flow &= ~htonl(0xff << 20); 74562587Sitojun ip6->ip6_flow |= htonl((u_int32_t)itos << 20); 74662587Sitojun 74762587Sitojun m->m_pkthdr.rcvif = ifp; 74862587Sitojun 749159180Scsjp if (bpf_peers_present(ifp->if_bpf)) { 75062587Sitojun /* 75162587Sitojun * We need to prepend the address family as 75262587Sitojun * a four byte field. Cons up a dummy header 75362587Sitojun * to pacify bpf. This is safe because bpf 75462587Sitojun * will only read from the mbuf (i.e., it won't 75562587Sitojun * try to free it or keep a pointer a to it). 75662587Sitojun */ 757123922Ssam u_int32_t af = AF_INET6; 758140042Sume bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m); 75962587Sitojun } 76062587Sitojun 76162587Sitojun /* 76262587Sitojun * Put the packet to the network layer input queue according to the 76362587Sitojun * specified address family. 76462587Sitojun * See net/if_gif.c for possible issues with packet processing 76562587Sitojun * reorder due to extra queueing. 76662587Sitojun */ 76762587Sitojun ifp->if_ipackets++; 768111888Sjlemon ifp->if_ibytes += m->m_pkthdr.len; 769223741Sbz M_SETFIB(m, ifp->if_fib); 770111888Sjlemon netisr_dispatch(NETISR_IPV6, m); 77162587Sitojun} 77262587Sitojun 77362587Sitojun/* ARGSUSED */ 77462587Sitojunstatic void 77585074Srustf_rtrequest(cmd, rt, info) 77662587Sitojun int cmd; 77762587Sitojun struct rtentry *rt; 77885074Sru struct rt_addrinfo *info; 77962587Sitojun{ 780120727Ssam RT_LOCK_ASSERT(rt); 781263478Sglebius rt->rt_mtu = rt->rt_ifp->if_mtu; 78262587Sitojun} 78362587Sitojun 78462587Sitojunstatic int 78562587Sitojunstf_ioctl(ifp, cmd, data) 78662587Sitojun struct ifnet *ifp; 78762587Sitojun u_long cmd; 78862587Sitojun caddr_t data; 78962587Sitojun{ 79062587Sitojun struct ifaddr *ifa; 79162587Sitojun struct ifreq *ifr; 79262587Sitojun struct sockaddr_in6 *sin6; 793109322Ssuz struct in_addr addr; 794238492Smelifaro int error, mtu; 79562587Sitojun 79662587Sitojun error = 0; 79762587Sitojun switch (cmd) { 79862587Sitojun case SIOCSIFADDR: 79962587Sitojun ifa = (struct ifaddr *)data; 80062587Sitojun if (ifa == NULL || ifa->ifa_addr->sa_family != AF_INET6) { 80162587Sitojun error = EAFNOSUPPORT; 80262587Sitojun break; 80362587Sitojun } 80462587Sitojun sin6 = (struct sockaddr_in6 *)ifa->ifa_addr; 805109322Ssuz if (!IN6_IS_ADDR_6TO4(&sin6->sin6_addr)) { 80662587Sitojun error = EINVAL; 807109322Ssuz break; 808109322Ssuz } 809109322Ssuz bcopy(GET_V4(&sin6->sin6_addr), &addr, sizeof(addr)); 810109322Ssuz if (isrfc1918addr(&addr)) { 811109322Ssuz error = EINVAL; 812109322Ssuz break; 813109322Ssuz } 814109322Ssuz 815109322Ssuz ifa->ifa_rtrequest = stf_rtrequest; 816109322Ssuz ifp->if_flags |= IFF_UP; 81762587Sitojun break; 81862587Sitojun 81962587Sitojun case SIOCADDMULTI: 82062587Sitojun case SIOCDELMULTI: 82162587Sitojun ifr = (struct ifreq *)data; 82262587Sitojun if (ifr && ifr->ifr_addr.sa_family == AF_INET6) 82362587Sitojun ; 82462587Sitojun else 82562587Sitojun error = EAFNOSUPPORT; 82662587Sitojun break; 82762587Sitojun 828238492Smelifaro case SIOCGIFMTU: 829238492Smelifaro break; 830238492Smelifaro 831238492Smelifaro case SIOCSIFMTU: 832238492Smelifaro ifr = (struct ifreq *)data; 833238492Smelifaro mtu = ifr->ifr_mtu; 834238492Smelifaro /* RFC 4213 3.2 ideal world MTU */ 835238492Smelifaro if (mtu < IPV6_MINMTU || mtu > IF_MAXMTU - 20) 836238492Smelifaro return (EINVAL); 837238492Smelifaro ifp->if_mtu = mtu; 838238492Smelifaro break; 839238492Smelifaro 84062587Sitojun default: 84162587Sitojun error = EINVAL; 84262587Sitojun break; 84362587Sitojun } 84462587Sitojun 84562587Sitojun return error; 84662587Sitojun} 847