if_gre.c revision 249925
1227825Stheraven/* $NetBSD: if_gre.c,v 1.49 2003/12/11 00:22:29 itojun Exp $ */ 2227825Stheraven/* $FreeBSD: head/sys/net/if_gre.c 249925 2013-04-26 12:50:32Z glebius $ */ 3227825Stheraven 4227825Stheraven/*- 5227825Stheraven * Copyright (c) 1998 The NetBSD Foundation, Inc. 6227825Stheraven * All rights reserved. 7227825Stheraven * 8227825Stheraven * This code is derived from software contributed to The NetBSD Foundation 9227825Stheraven * by Heiko W.Rupp <hwr@pilhuhn.de> 10227825Stheraven * 11227825Stheraven * IPv6-over-GRE contributed by Gert Doering <gert@greenie.muc.de> 12227825Stheraven * 13227825Stheraven * Redistribution and use in source and binary forms, with or without 14227825Stheraven * modification, are permitted provided that the following conditions 15227825Stheraven * are met: 16227825Stheraven * 1. Redistributions of source code must retain the above copyright 17227825Stheraven * notice, this list of conditions and the following disclaimer. 18227825Stheraven * 2. Redistributions in binary form must reproduce the above copyright 19227825Stheraven * notice, this list of conditions and the following disclaimer in the 20227825Stheraven * documentation and/or other materials provided with the distribution. 21227825Stheraven * 22227825Stheraven * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 23227825Stheraven * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 24227825Stheraven * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 25227825Stheraven * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 26227825Stheraven * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 27227825Stheraven * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 28227825Stheraven * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 29227825Stheraven * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 30227825Stheraven * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 31227825Stheraven * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 32227825Stheraven * POSSIBILITY OF SUCH DAMAGE. 33227825Stheraven */ 34227825Stheraven 35227825Stheraven/* 36227825Stheraven * Encapsulate L3 protocols into IP 37227825Stheraven * See RFC 2784 (successor of RFC 1701 and 1702) for more details. 38227825Stheraven * If_gre is compatible with Cisco GRE tunnels, so you can 39227825Stheraven * have a NetBSD box as the other end of a tunnel interface of a Cisco 40227825Stheraven * router. See gre(4) for more details. 41227825Stheraven * Also supported: IP in IP encaps (proto 55) as of RFC 2004 42227825Stheraven */ 43227825Stheraven 44227825Stheraven#include "opt_atalk.h" 45227825Stheraven#include "opt_inet.h" 46227825Stheraven#include "opt_inet6.h" 47227825Stheraven 48227825Stheraven#include <sys/param.h> 49227825Stheraven#include <sys/jail.h> 50227825Stheraven#include <sys/kernel.h> 51227825Stheraven#include <sys/libkern.h> 52227825Stheraven#include <sys/malloc.h> 53227825Stheraven#include <sys/module.h> 54227825Stheraven#include <sys/mbuf.h> 55227825Stheraven#include <sys/priv.h> 56227825Stheraven#include <sys/proc.h> 57227825Stheraven#include <sys/protosw.h> 58227825Stheraven#include <sys/socket.h> 59227825Stheraven#include <sys/sockio.h> 60227825Stheraven#include <sys/sysctl.h> 61227825Stheraven#include <sys/systm.h> 62227825Stheraven 63227825Stheraven#include <net/ethernet.h> 64227825Stheraven#include <net/if.h> 65227825Stheraven#include <net/if_clone.h> 66227825Stheraven#include <net/if_types.h> 67227825Stheraven#include <net/route.h> 68227825Stheraven#include <net/vnet.h> 69227825Stheraven 70227825Stheraven#ifdef INET 71227825Stheraven#include <netinet/in.h> 72227825Stheraven#include <netinet/in_systm.h> 73227825Stheraven#include <netinet/in_var.h> 74227825Stheraven#include <netinet/ip.h> 75227825Stheraven#include <netinet/ip_gre.h> 76227825Stheraven#include <netinet/ip_var.h> 77227825Stheraven#include <netinet/ip_encap.h> 78227825Stheraven#else 79227825Stheraven#error "Huh? if_gre without inet?" 80227825Stheraven#endif 81227825Stheraven 82227825Stheraven#include <net/bpf.h> 83227825Stheraven 84227825Stheraven#include <net/if_gre.h> 85227825Stheraven 86227825Stheraven/* 87227825Stheraven * It is not easy to calculate the right value for a GRE MTU. 88227825Stheraven * We leave this task to the admin and use the same default that 89227825Stheraven * other vendors use. 90227825Stheraven */ 91227825Stheraven#define GREMTU 1476 92227825Stheraven 93227825Stheraven#define MTAG_COOKIE_GRE 1307983903 94227825Stheraven#define MTAG_GRE_NESTING 1 95227825Stheravenstruct mtag_gre_nesting { 96227825Stheraven uint16_t count; 97227825Stheraven uint16_t max; 98227825Stheraven struct ifnet *ifp[]; 99227825Stheraven}; 100227825Stheraven 101227825Stheraven/* 102227825Stheraven * gre_mtx protects all global variables in if_gre.c. 103227825Stheraven * XXX: gre_softc data not protected yet. 104227825Stheraven */ 105227825Stheravenstruct mtx gre_mtx; 106227825Stheravenstatic const char grename[] = "gre"; 107227825Stheravenstatic MALLOC_DEFINE(M_GRE, grename, "Generic Routing Encapsulation"); 108227825Stheraven 109227825Stheravenstruct gre_softc_head gre_softc_list; 110227825Stheraven 111227825Stheravenstatic int gre_clone_create(struct if_clone *, int, caddr_t); 112227825Stheravenstatic void gre_clone_destroy(struct ifnet *); 113227825Stheravenstatic struct if_clone *gre_cloner; 114227825Stheraven 115227825Stheravenstatic int gre_ioctl(struct ifnet *, u_long, caddr_t); 116227825Stheravenstatic int gre_output(struct ifnet *, struct mbuf *, 117227825Stheraven const struct sockaddr *, struct route *); 118227825Stheraven 119227825Stheravenstatic int gre_compute_route(struct gre_softc *sc); 120227825Stheraven 121227825Stheravenstatic void greattach(void); 122227825Stheraven 123227825Stheraven#ifdef INET 124227825Stheravenextern struct domain inetdomain; 125227825Stheravenstatic const struct protosw in_gre_protosw = { 126227825Stheraven .pr_type = SOCK_RAW, 127227825Stheraven .pr_domain = &inetdomain, 128227825Stheraven .pr_protocol = IPPROTO_GRE, 129227825Stheraven .pr_flags = PR_ATOMIC|PR_ADDR, 130227825Stheraven .pr_input = gre_input, 131227825Stheraven .pr_output = (pr_output_t *)rip_output, 132227825Stheraven .pr_ctlinput = rip_ctlinput, 133227825Stheraven .pr_ctloutput = rip_ctloutput, 134227825Stheraven .pr_usrreqs = &rip_usrreqs 135227825Stheraven}; 136227825Stheravenstatic const struct protosw in_mobile_protosw = { 137227825Stheraven .pr_type = SOCK_RAW, 138227825Stheraven .pr_domain = &inetdomain, 139227825Stheraven .pr_protocol = IPPROTO_MOBILE, 140227825Stheraven .pr_flags = PR_ATOMIC|PR_ADDR, 141227825Stheraven .pr_input = gre_mobile_input, 142227825Stheraven .pr_output = (pr_output_t *)rip_output, 143227825Stheraven .pr_ctlinput = rip_ctlinput, 144227825Stheraven .pr_ctloutput = rip_ctloutput, 145227825Stheraven .pr_usrreqs = &rip_usrreqs 146227825Stheraven}; 147227825Stheraven#endif 148227825Stheraven 149227825StheravenSYSCTL_DECL(_net_link); 150227825Stheravenstatic SYSCTL_NODE(_net_link, IFT_TUNNEL, gre, CTLFLAG_RW, 0, 151227825Stheraven "Generic Routing Encapsulation"); 152227825Stheraven#ifndef MAX_GRE_NEST 153227825Stheraven/* 154227825Stheraven * This macro controls the default upper limitation on nesting of gre tunnels. 155227825Stheraven * Since, setting a large value to this macro with a careless configuration 156227825Stheraven * may introduce system crash, we don't allow any nestings by default. 157227825Stheraven * If you need to configure nested gre tunnels, you can define this macro 158232950Stheraven * in your kernel configuration file. However, if you do so, please be 159232950Stheraven * careful to configure the tunnels so that it won't make a loop. 160227825Stheraven */ 161227825Stheraven#define MAX_GRE_NEST 1 162227825Stheraven#endif 163227825Stheravenstatic int max_gre_nesting = MAX_GRE_NEST; 164227825StheravenSYSCTL_INT(_net_link_gre, OID_AUTO, max_nesting, CTLFLAG_RW, 165227825Stheraven &max_gre_nesting, 0, "Max nested tunnels"); 166227825Stheraven 167227825Stheraven/* ARGSUSED */ 168227825Stheravenstatic void 169227825Stheravengreattach(void) 170227825Stheraven{ 171227825Stheraven 172227825Stheraven mtx_init(&gre_mtx, "gre_mtx", NULL, MTX_DEF); 173227825Stheraven LIST_INIT(&gre_softc_list); 174227825Stheraven gre_cloner = if_clone_simple(grename, gre_clone_create, 175227825Stheraven gre_clone_destroy, 0); 176227825Stheraven} 177227825Stheraven 178227825Stheravenstatic int 179227825Stheravengre_clone_create(ifc, unit, params) 180227825Stheraven struct if_clone *ifc; 181227825Stheraven int unit; 182227825Stheraven caddr_t params; 183227825Stheraven{ 184227825Stheraven struct gre_softc *sc; 185227825Stheraven 186227825Stheraven sc = malloc(sizeof(struct gre_softc), M_GRE, M_WAITOK | M_ZERO); 187227825Stheraven 188227825Stheraven GRE2IFP(sc) = if_alloc(IFT_TUNNEL); 189227825Stheraven if (GRE2IFP(sc) == NULL) { 190227825Stheraven free(sc, M_GRE); 191227825Stheraven return (ENOSPC); 192227825Stheraven } 193227825Stheraven 194227825Stheraven GRE2IFP(sc)->if_softc = sc; 195227825Stheraven if_initname(GRE2IFP(sc), grename, unit); 196227825Stheraven 197241903Sdim GRE2IFP(sc)->if_snd.ifq_maxlen = ifqmaxlen; 198227825Stheraven GRE2IFP(sc)->if_addrlen = 0; 199227825Stheraven GRE2IFP(sc)->if_hdrlen = 24; /* IP + GRE */ 200227825Stheraven GRE2IFP(sc)->if_mtu = GREMTU; 201227825Stheraven GRE2IFP(sc)->if_flags = IFF_POINTOPOINT|IFF_MULTICAST; 202227825Stheraven GRE2IFP(sc)->if_output = gre_output; 203227825Stheraven GRE2IFP(sc)->if_ioctl = gre_ioctl; 204227825Stheraven sc->g_dst.s_addr = sc->g_src.s_addr = INADDR_ANY; 205227825Stheraven sc->g_proto = IPPROTO_GRE; 206227825Stheraven GRE2IFP(sc)->if_flags |= IFF_LINK0; 207227825Stheraven sc->encap = NULL; 208227825Stheraven sc->gre_fibnum = curthread->td_proc->p_fibnum; 209227825Stheraven sc->wccp_ver = WCCP_V1; 210227825Stheraven sc->key = 0; 211227825Stheraven if_attach(GRE2IFP(sc)); 212227825Stheraven bpfattach(GRE2IFP(sc), DLT_NULL, sizeof(u_int32_t)); 213227825Stheraven mtx_lock(&gre_mtx); 214227825Stheraven LIST_INSERT_HEAD(&gre_softc_list, sc, sc_list); 215227825Stheraven mtx_unlock(&gre_mtx); 216227825Stheraven return (0); 217227825Stheraven} 218227825Stheraven 219227825Stheravenstatic void 220227825Stheravengre_clone_destroy(ifp) 221227825Stheraven struct ifnet *ifp; 222227825Stheraven{ 223227825Stheraven struct gre_softc *sc = ifp->if_softc; 224227825Stheraven 225227825Stheraven mtx_lock(&gre_mtx); 226227825Stheraven LIST_REMOVE(sc, sc_list); 227227825Stheraven mtx_unlock(&gre_mtx); 228227825Stheraven 229227825Stheraven#ifdef INET 230227825Stheraven if (sc->encap != NULL) 231227825Stheraven encap_detach(sc->encap); 232227825Stheraven#endif 233227825Stheraven bpfdetach(ifp); 234227825Stheraven if_detach(ifp); 235227825Stheraven if_free(ifp); 236227825Stheraven free(sc, M_GRE); 237227825Stheraven} 238227825Stheraven 239227825Stheraven/* 240227825Stheraven * The output routine. Takes a packet and encapsulates it in the protocol 241227825Stheraven * given by sc->g_proto. See also RFC 1701 and RFC 2004 242227825Stheraven */ 243227825Stheravenstatic int 244227825Stheravengre_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst, 245227825Stheraven struct route *ro) 246227825Stheraven{ 247227825Stheraven int error = 0; 248227825Stheraven struct gre_softc *sc = ifp->if_softc; 249227825Stheraven struct greip *gh; 250227825Stheraven struct ip *ip; 251227825Stheraven struct m_tag *mtag; 252227825Stheraven struct mtag_gre_nesting *gt; 253227825Stheraven size_t len; 254227825Stheraven u_short gre_ip_id = 0; 255227825Stheraven uint8_t gre_ip_tos = 0; 256227825Stheraven u_int16_t etype = 0; 257227825Stheraven struct mobile_h mob_h; 258227825Stheraven u_int32_t af; 259232950Stheraven int extra = 0, max; 260227825Stheraven 261227825Stheraven /* 262227825Stheraven * gre may cause infinite recursion calls when misconfigured. High 263227825Stheraven * nesting level may cause stack exhaustion. We'll prevent this by 264227825Stheraven * detecting loops and by introducing upper limit. 265227825Stheraven */ 266227825Stheraven mtag = m_tag_locate(m, MTAG_COOKIE_GRE, MTAG_GRE_NESTING, NULL); 267227825Stheraven if (mtag != NULL) { 268227825Stheraven struct ifnet **ifp2; 269227825Stheraven 270227825Stheraven gt = (struct mtag_gre_nesting *)(mtag + 1); 271227825Stheraven gt->count++; 272227825Stheraven if (gt->count > min(gt->max,max_gre_nesting)) { 273227825Stheraven printf("%s: hit maximum recursion limit %u on %s\n", 274232950Stheraven __func__, gt->count - 1, ifp->if_xname); 275227825Stheraven m_freem(m); 276232950Stheraven error = EIO; /* is there better errno? */ 277232950Stheraven goto end; 278227825Stheraven } 279227825Stheraven 280227825Stheraven ifp2 = gt->ifp; 281227825Stheraven for (max = gt->count - 1; max > 0; max--) { 282227825Stheraven if (*ifp2 == ifp) 283227825Stheraven break; 284227825Stheraven ifp2++; 285227825Stheraven } 286227825Stheraven if (*ifp2 == ifp) { 287227825Stheraven printf("%s: detected loop with nexting %u on %s\n", 288227825Stheraven __func__, gt->count-1, ifp->if_xname); 289227825Stheraven m_freem(m); 290227825Stheraven error = EIO; /* is there better errno? */ 291227825Stheraven goto end; 292227825Stheraven } 293227825Stheraven *ifp2 = ifp; 294227825Stheraven 295227825Stheraven } else { 296227825Stheraven /* 297227825Stheraven * Given that people should NOT increase max_gre_nesting beyond 298227825Stheraven * their real needs, we allocate once per packet rather than 299227825Stheraven * allocating an mtag once per passing through gre. 300227825Stheraven * 301227825Stheraven * Note: the sysctl does not actually check for saneness, so we 302227825Stheraven * limit the maximum numbers of possible recursions here. 303227825Stheraven */ 304227825Stheraven max = imin(max_gre_nesting, 256); 305227825Stheraven /* If someone sets the sysctl <= 0, we want at least 1. */ 306227825Stheraven max = imax(max, 1); 307227825Stheraven len = sizeof(struct mtag_gre_nesting) + 308227825Stheraven max * sizeof(struct ifnet *); 309227825Stheraven mtag = m_tag_alloc(MTAG_COOKIE_GRE, MTAG_GRE_NESTING, len, 310227825Stheraven M_NOWAIT); 311227825Stheraven if (mtag == NULL) { 312227825Stheraven m_freem(m); 313227825Stheraven error = ENOMEM; 314227825Stheraven goto end; 315227825Stheraven } 316227825Stheraven gt = (struct mtag_gre_nesting *)(mtag + 1); 317227825Stheraven bzero(gt, len); 318227825Stheraven gt->count = 1; 319227825Stheraven gt->max = max; 320227825Stheraven *gt->ifp = ifp; 321227825Stheraven m_tag_prepend(m, mtag); 322227825Stheraven } 323227825Stheraven 324227825Stheraven if (!((ifp->if_flags & IFF_UP) && 325227825Stheraven (ifp->if_drv_flags & IFF_DRV_RUNNING)) || 326227825Stheraven sc->g_src.s_addr == INADDR_ANY || sc->g_dst.s_addr == INADDR_ANY) { 327227825Stheraven m_freem(m); 328227825Stheraven error = ENETDOWN; 329227825Stheraven goto end; 330227825Stheraven } 331227825Stheraven 332227825Stheraven gh = NULL; 333227825Stheraven ip = NULL; 334227825Stheraven 335227825Stheraven /* BPF writes need to be handled specially. */ 336227825Stheraven if (dst->sa_family == AF_UNSPEC) 337227825Stheraven bcopy(dst->sa_data, &af, sizeof(af)); 338227825Stheraven else 339227825Stheraven af = dst->sa_family; 340227825Stheraven 341227825Stheraven if (bpf_peers_present(ifp->if_bpf)) 342227825Stheraven bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m); 343227825Stheraven 344227825Stheraven m->m_flags &= ~(M_BCAST|M_MCAST); 345232950Stheraven 346232950Stheraven if (sc->g_proto == IPPROTO_MOBILE) { 347227825Stheraven if (af == AF_INET) { 348232950Stheraven struct mbuf *m0; 349227825Stheraven int msiz; 350227825Stheraven 351227825Stheraven ip = mtod(m, struct ip *); 352227825Stheraven 353227825Stheraven /* 354227825Stheraven * RFC2004 specifies that fragmented diagrams shouldn't 355227825Stheraven * be encapsulated. 356227825Stheraven */ 357227825Stheraven if (ip->ip_off & htons(IP_MF | IP_OFFMASK)) { 358227825Stheraven _IF_DROP(&ifp->if_snd); 359227825Stheraven m_freem(m); 360227825Stheraven error = EINVAL; /* is there better errno? */ 361227825Stheraven goto end; 362227825Stheraven } 363227825Stheraven memset(&mob_h, 0, MOB_H_SIZ_L); 364227825Stheraven mob_h.proto = (ip->ip_p) << 8; 365227825Stheraven mob_h.odst = ip->ip_dst.s_addr; 366227825Stheraven ip->ip_dst.s_addr = sc->g_dst.s_addr; 367227825Stheraven 368227825Stheraven /* 369227825Stheraven * If the packet comes from our host, we only change 370227825Stheraven * the destination address in the IP header. 371227825Stheraven * Else we also need to save and change the source 372232950Stheraven */ 373232950Stheraven if (in_hosteq(ip->ip_src, sc->g_src)) { 374227825Stheraven msiz = MOB_H_SIZ_S; 375232950Stheraven } else { 376227825Stheraven mob_h.proto |= MOB_H_SBIT; 377227825Stheraven mob_h.osrc = ip->ip_src.s_addr; 378227825Stheraven ip->ip_src.s_addr = sc->g_src.s_addr; 379227825Stheraven msiz = MOB_H_SIZ_L; 380227825Stheraven } 381227825Stheraven mob_h.proto = htons(mob_h.proto); 382227825Stheraven mob_h.hcrc = gre_in_cksum((u_int16_t *)&mob_h, msiz); 383227825Stheraven 384227825Stheraven if ((m->m_data - msiz) < m->m_pktdat) { 385227825Stheraven m0 = m_gethdr(M_NOWAIT, MT_DATA); 386227825Stheraven if (m0 == NULL) { 387227825Stheraven _IF_DROP(&ifp->if_snd); 388227825Stheraven m_freem(m); 389227825Stheraven error = ENOBUFS; 390227825Stheraven goto end; 391227825Stheraven } 392227825Stheraven m0->m_next = m; 393227825Stheraven m->m_data += sizeof(struct ip); 394227825Stheraven m->m_len -= sizeof(struct ip); 395227825Stheraven m0->m_pkthdr.len = m->m_pkthdr.len + msiz; 396227825Stheraven m0->m_len = msiz + sizeof(struct ip); 397227825Stheraven m0->m_data += max_linkhdr; 398227825Stheraven memcpy(mtod(m0, caddr_t), (caddr_t)ip, 399232950Stheraven sizeof(struct ip)); 400232950Stheraven m = m0; 401227825Stheraven } else { /* we have some space left in the old one */ 402232950Stheraven m->m_data -= msiz; 403227825Stheraven m->m_len += msiz; 404227825Stheraven m->m_pkthdr.len += msiz; 405227825Stheraven bcopy(ip, mtod(m, caddr_t), 406227825Stheraven sizeof(struct ip)); 407227825Stheraven } 408227825Stheraven ip = mtod(m, struct ip *); 409227825Stheraven memcpy((caddr_t)(ip + 1), &mob_h, (unsigned)msiz); 410227825Stheraven ip->ip_len = htons(ntohs(ip->ip_len) + msiz); 411227825Stheraven } else { /* AF_INET */ 412227825Stheraven _IF_DROP(&ifp->if_snd); 413227825Stheraven m_freem(m); 414227825Stheraven error = EINVAL; 415227825Stheraven goto end; 416227825Stheraven } 417227825Stheraven } else if (sc->g_proto == IPPROTO_GRE) { 418227825Stheraven switch (af) { 419227825Stheraven case AF_INET: 420227825Stheraven ip = mtod(m, struct ip *); 421227825Stheraven gre_ip_tos = ip->ip_tos; 422227825Stheraven gre_ip_id = ip->ip_id; 423227825Stheraven if (sc->wccp_ver == WCCP_V2) { 424227825Stheraven extra = sizeof(uint32_t); 425227825Stheraven etype = WCCP_PROTOCOL_TYPE; 426232950Stheraven } else { 427232950Stheraven etype = ETHERTYPE_IP; 428227825Stheraven } 429232950Stheraven break; 430227825Stheraven#ifdef INET6 431227825Stheraven case AF_INET6: 432227825Stheraven gre_ip_id = ip_newid(); 433227825Stheraven etype = ETHERTYPE_IPV6; 434227825Stheraven break; 435227825Stheraven#endif 436227825Stheraven#ifdef NETATALK 437227825Stheraven case AF_APPLETALK: 438227825Stheraven etype = ETHERTYPE_ATALK; 439227825Stheraven break; 440227825Stheraven#endif 441227825Stheraven default: 442227825Stheraven _IF_DROP(&ifp->if_snd); 443227825Stheraven m_freem(m); 444227825Stheraven error = EAFNOSUPPORT; 445227825Stheraven goto end; 446227825Stheraven } 447227825Stheraven 448227825Stheraven /* Reserve space for GRE header + optional GRE key */ 449227825Stheraven int hdrlen = sizeof(struct greip) + extra; 450227825Stheraven if (sc->key) 451227825Stheraven hdrlen += sizeof(uint32_t); 452227825Stheraven M_PREPEND(m, hdrlen, M_NOWAIT); 453232950Stheraven } else { 454232950Stheraven _IF_DROP(&ifp->if_snd); 455227825Stheraven m_freem(m); 456232950Stheraven error = EINVAL; 457227825Stheraven goto end; 458227825Stheraven } 459227825Stheraven 460227825Stheraven if (m == NULL) { /* mbuf allocation failed */ 461227825Stheraven _IF_DROP(&ifp->if_snd); 462227825Stheraven error = ENOBUFS; 463227825Stheraven goto end; 464227825Stheraven } 465227825Stheraven 466227825Stheraven M_SETFIB(m, sc->gre_fibnum); /* The envelope may use a different FIB */ 467227825Stheraven 468227825Stheraven gh = mtod(m, struct greip *); 469227825Stheraven if (sc->g_proto == IPPROTO_GRE) { 470227825Stheraven uint32_t *options = gh->gi_options; 471227825Stheraven 472227825Stheraven memset((void *)gh, 0, sizeof(struct greip) + extra); 473227825Stheraven gh->gi_ptype = htons(etype); 474227825Stheraven gh->gi_flags = 0; 475227825Stheraven 476227825Stheraven /* Add key option */ 477227825Stheraven if (sc->key) 478227825Stheraven { 479227825Stheraven gh->gi_flags |= htons(GRE_KP); 480232950Stheraven *(options++) = htonl(sc->key); 481232950Stheraven } 482227825Stheraven } 483232950Stheraven 484227825Stheraven gh->gi_pr = sc->g_proto; 485227825Stheraven if (sc->g_proto != IPPROTO_MOBILE) { 486227825Stheraven gh->gi_src = sc->g_src; 487227825Stheraven gh->gi_dst = sc->g_dst; 488227825Stheraven ((struct ip*)gh)->ip_v = IPPROTO_IPV4; 489227825Stheraven ((struct ip*)gh)->ip_hl = (sizeof(struct ip)) >> 2; 490227825Stheraven ((struct ip*)gh)->ip_ttl = GRE_TTL; 491227825Stheraven ((struct ip*)gh)->ip_tos = gre_ip_tos; 492227825Stheraven ((struct ip*)gh)->ip_id = gre_ip_id; 493227825Stheraven gh->gi_len = htons(m->m_pkthdr.len); 494227825Stheraven } 495227825Stheraven 496227825Stheraven ifp->if_opackets++; 497227825Stheraven ifp->if_obytes += m->m_pkthdr.len; 498227825Stheraven /* 499227825Stheraven * Send it off and with IP_FORWARD flag to prevent it from 500227825Stheraven * overwriting the ip_id again. ip_id is already set to the 501227825Stheraven * ip_id of the encapsulated packet. 502227825Stheraven */ 503227825Stheraven error = ip_output(m, NULL, &sc->route, IP_FORWARDING, 504227825Stheraven (struct ip_moptions *)NULL, (struct inpcb *)NULL); 505227825Stheraven end: 506227825Stheraven if (error) 507232950Stheraven ifp->if_oerrors++; 508232950Stheraven return (error); 509227825Stheraven} 510232950Stheraven 511227825Stheravenstatic int 512227825Stheravengre_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data) 513227825Stheraven{ 514227825Stheraven struct ifreq *ifr = (struct ifreq *)data; 515227825Stheraven struct if_laddrreq *lifr = (struct if_laddrreq *)data; 516227825Stheraven struct in_aliasreq *aifr = (struct in_aliasreq *)data; 517227825Stheraven struct gre_softc *sc = ifp->if_softc; 518227825Stheraven struct sockaddr_in si; 519227825Stheraven struct sockaddr *sa = NULL; 520227825Stheraven int error, adj; 521227825Stheraven struct sockaddr_in sp, sm, dp, dm; 522227825Stheraven uint32_t key; 523227825Stheraven 524227825Stheraven error = 0; 525227825Stheraven adj = 0; 526227825Stheraven 527227825Stheraven switch (cmd) { 528227825Stheraven case SIOCSIFADDR: 529227825Stheraven ifp->if_flags |= IFF_UP; 530227825Stheraven break; 531227825Stheraven case SIOCSIFDSTADDR: 532227825Stheraven break; 533227825Stheraven case SIOCSIFFLAGS: 534232950Stheraven /* 535232950Stheraven * XXXRW: Isn't this priv_check() redundant to the ifnet 536227825Stheraven * layer check? 537232950Stheraven */ 538227825Stheraven if ((error = priv_check(curthread, PRIV_NET_SETIFFLAGS)) != 0) 539227825Stheraven break; 540227825Stheraven if ((ifr->ifr_flags & IFF_LINK0) != 0) 541227825Stheraven sc->g_proto = IPPROTO_GRE; 542227825Stheraven else 543227825Stheraven sc->g_proto = IPPROTO_MOBILE; 544227825Stheraven if ((ifr->ifr_flags & IFF_LINK2) != 0) 545227825Stheraven sc->wccp_ver = WCCP_V2; 546227825Stheraven else 547227825Stheraven sc->wccp_ver = WCCP_V1; 548227825Stheraven goto recompute; 549227825Stheraven case SIOCSIFMTU: 550227825Stheraven /* 551227825Stheraven * XXXRW: Isn't this priv_check() redundant to the ifnet 552227825Stheraven * layer check? 553227825Stheraven */ 554227825Stheraven if ((error = priv_check(curthread, PRIV_NET_SETIFMTU)) != 0) 555227825Stheraven break; 556227825Stheraven if (ifr->ifr_mtu < 576) { 557227825Stheraven error = EINVAL; 558227825Stheraven break; 559227825Stheraven } 560227825Stheraven ifp->if_mtu = ifr->ifr_mtu; 561232950Stheraven break; 562232950Stheraven case SIOCGIFMTU: 563227825Stheraven ifr->ifr_mtu = GRE2IFP(sc)->if_mtu; 564232950Stheraven break; 565227825Stheraven case SIOCADDMULTI: 566227825Stheraven /* 567227825Stheraven * XXXRW: Isn't this priv_checkr() redundant to the ifnet 568227825Stheraven * layer check? 569227825Stheraven */ 570227825Stheraven if ((error = priv_check(curthread, PRIV_NET_ADDMULTI)) != 0) 571227825Stheraven break; 572227825Stheraven if (ifr == 0) { 573227825Stheraven error = EAFNOSUPPORT; 574227825Stheraven break; 575227825Stheraven } 576227825Stheraven switch (ifr->ifr_addr.sa_family) { 577227825Stheraven#ifdef INET 578227825Stheraven case AF_INET: 579227825Stheraven break; 580227825Stheraven#endif 581227825Stheraven#ifdef INET6 582227825Stheraven case AF_INET6: 583227825Stheraven break; 584227825Stheraven#endif 585227825Stheraven default: 586227825Stheraven error = EAFNOSUPPORT; 587227825Stheraven break; 588232950Stheraven } 589232950Stheraven break; 590227825Stheraven case SIOCDELMULTI: 591232950Stheraven /* 592227825Stheraven * XXXRW: Isn't this priv_check() redundant to the ifnet 593227825Stheraven * layer check? 594227825Stheraven */ 595227825Stheraven if ((error = priv_check(curthread, PRIV_NET_DELIFGROUP)) != 0) 596227825Stheraven break; 597227825Stheraven if (ifr == 0) { 598227825Stheraven error = EAFNOSUPPORT; 599227825Stheraven break; 600227825Stheraven } 601227825Stheraven switch (ifr->ifr_addr.sa_family) { 602227825Stheraven#ifdef INET 603227825Stheraven case AF_INET: 604227825Stheraven break; 605227825Stheraven#endif 606227825Stheraven#ifdef INET6 607227825Stheraven case AF_INET6: 608227825Stheraven break; 609227825Stheraven#endif 610227825Stheraven default: 611227825Stheraven error = EAFNOSUPPORT; 612227825Stheraven break; 613227825Stheraven } 614227825Stheraven break; 615232950Stheraven case GRESPROTO: 616232950Stheraven /* 617227825Stheraven * XXXRW: Isn't this priv_check() redundant to the ifnet 618232950Stheraven * layer check? 619227825Stheraven */ 620227825Stheraven if ((error = priv_check(curthread, PRIV_NET_GRE)) != 0) 621227825Stheraven break; 622227825Stheraven sc->g_proto = ifr->ifr_flags; 623227825Stheraven switch (sc->g_proto) { 624227825Stheraven case IPPROTO_GRE: 625227825Stheraven ifp->if_flags |= IFF_LINK0; 626227825Stheraven break; 627227825Stheraven case IPPROTO_MOBILE: 628227825Stheraven ifp->if_flags &= ~IFF_LINK0; 629227825Stheraven break; 630227825Stheraven default: 631227825Stheraven error = EPROTONOSUPPORT; 632227825Stheraven break; 633227825Stheraven } 634227825Stheraven goto recompute; 635227825Stheraven case GREGPROTO: 636227825Stheraven ifr->ifr_flags = sc->g_proto; 637227825Stheraven break; 638227825Stheraven case GRESADDRS: 639227825Stheraven case GRESADDRD: 640227825Stheraven error = priv_check(curthread, PRIV_NET_GRE); 641227825Stheraven if (error) 642232950Stheraven return (error); 643232950Stheraven /* 644227825Stheraven * set tunnel endpoints, compute a less specific route 645227825Stheraven * to the remote end and mark if as up 646232950Stheraven */ 647227825Stheraven sa = &ifr->ifr_addr; 648227825Stheraven if (cmd == GRESADDRS) 649227825Stheraven sc->g_src = (satosin(sa))->sin_addr; 650227825Stheraven if (cmd == GRESADDRD) 651227825Stheraven sc->g_dst = (satosin(sa))->sin_addr; 652227825Stheraven recompute: 653227825Stheraven#ifdef INET 654227825Stheraven if (sc->encap != NULL) { 655227825Stheraven encap_detach(sc->encap); 656227825Stheraven sc->encap = NULL; 657227825Stheraven } 658227825Stheraven#endif 659227825Stheraven if ((sc->g_src.s_addr != INADDR_ANY) && 660227825Stheraven (sc->g_dst.s_addr != INADDR_ANY)) { 661227825Stheraven bzero(&sp, sizeof(sp)); 662227825Stheraven bzero(&sm, sizeof(sm)); 663227825Stheraven bzero(&dp, sizeof(dp)); 664227825Stheraven bzero(&dm, sizeof(dm)); 665227825Stheraven sp.sin_len = sm.sin_len = dp.sin_len = dm.sin_len = 666227825Stheraven sizeof(struct sockaddr_in); 667227825Stheraven sp.sin_family = sm.sin_family = dp.sin_family = 668227825Stheraven dm.sin_family = AF_INET; 669227825Stheraven sp.sin_addr = sc->g_src; 670227825Stheraven dp.sin_addr = sc->g_dst; 671227825Stheraven sm.sin_addr.s_addr = dm.sin_addr.s_addr = 672227825Stheraven INADDR_BROADCAST; 673227825Stheraven#ifdef INET 674227825Stheraven sc->encap = encap_attach(AF_INET, sc->g_proto, 675227825Stheraven sintosa(&sp), sintosa(&sm), sintosa(&dp), 676227825Stheraven sintosa(&dm), (sc->g_proto == IPPROTO_GRE) ? 677227825Stheraven &in_gre_protosw : &in_mobile_protosw, sc); 678227825Stheraven if (sc->encap == NULL) 679227825Stheraven printf("%s: unable to attach encap\n", 680227825Stheraven if_name(GRE2IFP(sc))); 681227825Stheraven#endif 682232950Stheraven if (sc->route.ro_rt != 0) /* free old route */ 683232950Stheraven RTFREE(sc->route.ro_rt); 684227825Stheraven if (gre_compute_route(sc) == 0) 685227825Stheraven ifp->if_drv_flags |= IFF_DRV_RUNNING; 686232950Stheraven else 687227825Stheraven ifp->if_drv_flags &= ~IFF_DRV_RUNNING; 688227825Stheraven } 689227825Stheraven break; 690227825Stheraven case GREGADDRS: 691227825Stheraven memset(&si, 0, sizeof(si)); 692227825Stheraven si.sin_family = AF_INET; 693227825Stheraven si.sin_len = sizeof(struct sockaddr_in); 694227825Stheraven si.sin_addr.s_addr = sc->g_src.s_addr; 695227825Stheraven sa = sintosa(&si); 696227825Stheraven error = prison_if(curthread->td_ucred, sa); 697227825Stheraven if (error != 0) 698227825Stheraven break; 699227825Stheraven ifr->ifr_addr = *sa; 700227825Stheraven break; 701227825Stheraven case GREGADDRD: 702227825Stheraven memset(&si, 0, sizeof(si)); 703227825Stheraven si.sin_family = AF_INET; 704227825Stheraven si.sin_len = sizeof(struct sockaddr_in); 705227825Stheraven si.sin_addr.s_addr = sc->g_dst.s_addr; 706227825Stheraven sa = sintosa(&si); 707227825Stheraven error = prison_if(curthread->td_ucred, sa); 708227825Stheraven if (error != 0) 709227825Stheraven break; 710227825Stheraven ifr->ifr_addr = *sa; 711227825Stheraven break; 712227825Stheraven case SIOCSIFPHYADDR: 713227825Stheraven /* 714227825Stheraven * XXXRW: Isn't this priv_check() redundant to the ifnet 715227825Stheraven * layer check? 716227825Stheraven */ 717227825Stheraven if ((error = priv_check(curthread, PRIV_NET_SETIFPHYS)) != 0) 718227825Stheraven break; 719227825Stheraven if (aifr->ifra_addr.sin_family != AF_INET || 720227825Stheraven aifr->ifra_dstaddr.sin_family != AF_INET) { 721227825Stheraven error = EAFNOSUPPORT; 722227825Stheraven break; 723227825Stheraven } 724227825Stheraven if (aifr->ifra_addr.sin_len != sizeof(si) || 725227825Stheraven aifr->ifra_dstaddr.sin_len != sizeof(si)) { 726227825Stheraven error = EINVAL; 727227825Stheraven break; 728227825Stheraven } 729227825Stheraven sc->g_src = aifr->ifra_addr.sin_addr; 730227825Stheraven sc->g_dst = aifr->ifra_dstaddr.sin_addr; 731227825Stheraven goto recompute; 732227825Stheraven case SIOCSLIFPHYADDR: 733227825Stheraven /* 734227825Stheraven * XXXRW: Isn't this priv_check() redundant to the ifnet 735227825Stheraven * layer check? 736227825Stheraven */ 737227825Stheraven if ((error = priv_check(curthread, PRIV_NET_SETIFPHYS)) != 0) 738227825Stheraven break; 739227825Stheraven if (lifr->addr.ss_family != AF_INET || 740227825Stheraven lifr->dstaddr.ss_family != AF_INET) { 741227825Stheraven error = EAFNOSUPPORT; 742227825Stheraven break; 743227825Stheraven } 744227825Stheraven if (lifr->addr.ss_len != sizeof(si) || 745227825Stheraven lifr->dstaddr.ss_len != sizeof(si)) { 746227825Stheraven error = EINVAL; 747227825Stheraven break; 748227825Stheraven } 749227825Stheraven sc->g_src = (satosin(&lifr->addr))->sin_addr; 750227825Stheraven sc->g_dst = 751227825Stheraven (satosin(&lifr->dstaddr))->sin_addr; 752227825Stheraven goto recompute; 753227825Stheraven case SIOCDIFPHYADDR: 754227825Stheraven /* 755227825Stheraven * XXXRW: Isn't this priv_check() redundant to the ifnet 756227825Stheraven * layer check? 757227825Stheraven */ 758227825Stheraven if ((error = priv_check(curthread, PRIV_NET_SETIFPHYS)) != 0) 759227825Stheraven break; 760227825Stheraven sc->g_src.s_addr = INADDR_ANY; 761227825Stheraven sc->g_dst.s_addr = INADDR_ANY; 762227825Stheraven goto recompute; 763227825Stheraven case SIOCGLIFPHYADDR: 764227825Stheraven if (sc->g_src.s_addr == INADDR_ANY || 765227825Stheraven sc->g_dst.s_addr == INADDR_ANY) { 766227825Stheraven error = EADDRNOTAVAIL; 767227825Stheraven break; 768227825Stheraven } 769227825Stheraven memset(&si, 0, sizeof(si)); 770227825Stheraven si.sin_family = AF_INET; 771227825Stheraven si.sin_len = sizeof(struct sockaddr_in); 772227825Stheraven si.sin_addr.s_addr = sc->g_src.s_addr; 773227825Stheraven error = prison_if(curthread->td_ucred, (struct sockaddr *)&si); 774227825Stheraven if (error != 0) 775227825Stheraven break; 776227825Stheraven memcpy(&lifr->addr, &si, sizeof(si)); 777227825Stheraven si.sin_addr.s_addr = sc->g_dst.s_addr; 778227825Stheraven error = prison_if(curthread->td_ucred, (struct sockaddr *)&si); 779227825Stheraven if (error != 0) 780227825Stheraven break; 781227825Stheraven memcpy(&lifr->dstaddr, &si, sizeof(si)); 782227825Stheraven break; 783227825Stheraven case SIOCGIFPSRCADDR: 784227825Stheraven#ifdef INET6 785227825Stheraven case SIOCGIFPSRCADDR_IN6: 786227825Stheraven#endif 787227825Stheraven if (sc->g_src.s_addr == INADDR_ANY) { 788227825Stheraven error = EADDRNOTAVAIL; 789227825Stheraven break; 790227825Stheraven } 791227825Stheraven memset(&si, 0, sizeof(si)); 792227825Stheraven si.sin_family = AF_INET; 793227825Stheraven si.sin_len = sizeof(struct sockaddr_in); 794227825Stheraven si.sin_addr.s_addr = sc->g_src.s_addr; 795227825Stheraven error = prison_if(curthread->td_ucred, (struct sockaddr *)&si); 796227825Stheraven if (error != 0) 797227825Stheraven break; 798227825Stheraven bcopy(&si, &ifr->ifr_addr, sizeof(ifr->ifr_addr)); 799227825Stheraven break; 800227825Stheraven case SIOCGIFPDSTADDR: 801227825Stheraven#ifdef INET6 802227825Stheraven case SIOCGIFPDSTADDR_IN6: 803227825Stheraven#endif 804227825Stheraven if (sc->g_dst.s_addr == INADDR_ANY) { 805227825Stheraven error = EADDRNOTAVAIL; 806227825Stheraven break; 807227825Stheraven } 808227825Stheraven memset(&si, 0, sizeof(si)); 809227825Stheraven si.sin_family = AF_INET; 810227825Stheraven si.sin_len = sizeof(struct sockaddr_in); 811227825Stheraven si.sin_addr.s_addr = sc->g_dst.s_addr; 812227825Stheraven error = prison_if(curthread->td_ucred, (struct sockaddr *)&si); 813227825Stheraven if (error != 0) 814227825Stheraven break; 815227825Stheraven bcopy(&si, &ifr->ifr_addr, sizeof(ifr->ifr_addr)); 816227825Stheraven break; 817227825Stheraven case GRESKEY: 818227825Stheraven error = priv_check(curthread, PRIV_NET_GRE); 819227825Stheraven if (error) 820227825Stheraven break; 821227825Stheraven error = copyin(ifr->ifr_data, &key, sizeof(key)); 822227825Stheraven if (error) 823227825Stheraven break; 824227825Stheraven /* adjust MTU for option header */ 825227825Stheraven if (key == 0 && sc->key != 0) /* clear */ 826227825Stheraven adj += sizeof(key); 827227825Stheraven else if (key != 0 && sc->key == 0) /* set */ 828227825Stheraven adj -= sizeof(key); 829227825Stheraven 830227825Stheraven if (ifp->if_mtu + adj < 576) { 831227825Stheraven error = EINVAL; 832227825Stheraven break; 833227825Stheraven } 834227825Stheraven ifp->if_mtu += adj; 835227825Stheraven sc->key = key; 836227825Stheraven break; 837227825Stheraven case GREGKEY: 838227825Stheraven error = copyout(&sc->key, ifr->ifr_data, sizeof(sc->key)); 839227825Stheraven break; 840227825Stheraven 841227825Stheraven default: 842227825Stheraven error = EINVAL; 843227825Stheraven break; 844227825Stheraven } 845227825Stheraven 846227825Stheraven return (error); 847227825Stheraven} 848227825Stheraven 849227825Stheraven/* 850227825Stheraven * computes a route to our destination that is not the one 851227825Stheraven * which would be taken by ip_output(), as this one will loop back to 852227825Stheraven * us. If the interface is p2p as a--->b, then a routing entry exists 853227825Stheraven * If we now send a packet to b (e.g. ping b), this will come down here 854227825Stheraven * gets src=a, dst=b tacked on and would from ip_output() sent back to 855227825Stheraven * if_gre. 856227825Stheraven * Goal here is to compute a route to b that is less specific than 857227825Stheraven * a-->b. We know that this one exists as in normal operation we have 858227825Stheraven * at least a default route which matches. 859227825Stheraven */ 860227825Stheravenstatic int 861227825Stheravengre_compute_route(struct gre_softc *sc) 862227825Stheraven{ 863227825Stheraven struct route *ro; 864227825Stheraven 865227825Stheraven ro = &sc->route; 866227825Stheraven 867227825Stheraven memset(ro, 0, sizeof(struct route)); 868227825Stheraven ((struct sockaddr_in *)&ro->ro_dst)->sin_addr = sc->g_dst; 869227825Stheraven ro->ro_dst.sa_family = AF_INET; 870227825Stheraven ro->ro_dst.sa_len = sizeof(ro->ro_dst); 871227825Stheraven 872227825Stheraven /* 873227825Stheraven * toggle last bit, so our interface is not found, but a less 874227825Stheraven * specific route. I'd rather like to specify a shorter mask, 875227825Stheraven * but this is not possible. Should work though. XXX 876227825Stheraven * XXX MRT Use a different FIB for the tunnel to solve this problem. 877227825Stheraven */ 878227825Stheraven if ((GRE2IFP(sc)->if_flags & IFF_LINK1) == 0) { 879227825Stheraven ((struct sockaddr_in *)&ro->ro_dst)->sin_addr.s_addr ^= 880227825Stheraven htonl(0x01); 881227825Stheraven } 882227825Stheraven 883227825Stheraven#ifdef DIAGNOSTIC 884227825Stheraven printf("%s: searching for a route to %s", if_name(GRE2IFP(sc)), 885227825Stheraven inet_ntoa(((struct sockaddr_in *)&ro->ro_dst)->sin_addr)); 886227825Stheraven#endif 887227825Stheraven 888227825Stheraven rtalloc_fib(ro, sc->gre_fibnum); 889227825Stheraven 890227825Stheraven /* 891227825Stheraven * check if this returned a route at all and this route is no 892227825Stheraven * recursion to ourself 893227825Stheraven */ 894227825Stheraven if (ro->ro_rt == NULL || ro->ro_rt->rt_ifp->if_softc == sc) { 895227825Stheraven#ifdef DIAGNOSTIC 896227825Stheraven if (ro->ro_rt == NULL) 897227825Stheraven printf(" - no route found!\n"); 898227825Stheraven else 899227825Stheraven printf(" - route loops back to ourself!\n"); 900227825Stheraven#endif 901227825Stheraven return EADDRNOTAVAIL; 902227825Stheraven } 903227825Stheraven 904227825Stheraven /* 905227825Stheraven * now change it back - else ip_output will just drop 906227825Stheraven * the route and search one to this interface ... 907227825Stheraven */ 908227825Stheraven if ((GRE2IFP(sc)->if_flags & IFF_LINK1) == 0) 909227825Stheraven ((struct sockaddr_in *)&ro->ro_dst)->sin_addr = sc->g_dst; 910227825Stheraven 911227825Stheraven#ifdef DIAGNOSTIC 912227825Stheraven printf(", choosing %s with gateway %s", if_name(ro->ro_rt->rt_ifp), 913227825Stheraven inet_ntoa(((struct sockaddr_in *)(ro->ro_rt->rt_gateway))->sin_addr)); 914227825Stheraven printf("\n"); 915227825Stheraven#endif 916227825Stheraven 917227825Stheraven return 0; 918227825Stheraven} 919227825Stheraven 920227825Stheraven/* 921227825Stheraven * do a checksum of a buffer - much like in_cksum, which operates on 922227825Stheraven * mbufs. 923227825Stheraven */ 924227825Stheravenu_int16_t 925227825Stheravengre_in_cksum(u_int16_t *p, u_int len) 926227825Stheraven{ 927227825Stheraven u_int32_t sum = 0; 928227825Stheraven int nwords = len >> 1; 929227825Stheraven 930227825Stheraven while (nwords-- != 0) 931227825Stheraven sum += *p++; 932227825Stheraven 933227825Stheraven if (len & 1) { 934227825Stheraven union { 935227825Stheraven u_short w; 936227825Stheraven u_char c[2]; 937227825Stheraven } u; 938227825Stheraven u.c[0] = *(u_char *)p; 939227825Stheraven u.c[1] = 0; 940227825Stheraven sum += u.w; 941227825Stheraven } 942227825Stheraven 943227825Stheraven /* end-around-carry */ 944227825Stheraven sum = (sum >> 16) + (sum & 0xffff); 945227825Stheraven sum += (sum >> 16); 946227825Stheraven return (~sum); 947227825Stheraven} 948227825Stheraven 949227825Stheravenstatic int 950227825Stheravengremodevent(module_t mod, int type, void *data) 951227825Stheraven{ 952227825Stheraven 953227825Stheraven switch (type) { 954227825Stheraven case MOD_LOAD: 955227825Stheraven greattach(); 956227825Stheraven break; 957227825Stheraven case MOD_UNLOAD: 958227825Stheraven if_clone_detach(gre_cloner); 959227825Stheraven mtx_destroy(&gre_mtx); 960227825Stheraven break; 961227825Stheraven default: 962227825Stheraven return EOPNOTSUPP; 963227825Stheraven } 964227825Stheraven return 0; 965227825Stheraven} 966227825Stheraven 967227825Stheravenstatic moduledata_t gre_mod = { 968227825Stheraven "if_gre", 969227825Stheraven gremodevent, 970227825Stheraven 0 971227825Stheraven}; 972227825Stheraven 973227825StheravenDECLARE_MODULE(if_gre, gre_mod, SI_SUB_PSEUDO, SI_ORDER_ANY); 974227825StheravenMODULE_VERSION(if_gre, 1); 975227825Stheraven