if_me.c revision 284074
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/net/if_me.c 284074 2015-06-06 13:37:11Z ae $"); 29 30#include <sys/param.h> 31#include <sys/jail.h> 32#include <sys/kernel.h> 33#include <sys/lock.h> 34#include <sys/libkern.h> 35#include <sys/malloc.h> 36#include <sys/module.h> 37#include <sys/mbuf.h> 38#include <sys/priv.h> 39#include <sys/proc.h> 40#include <sys/protosw.h> 41#include <sys/rmlock.h> 42#include <sys/socket.h> 43#include <sys/sockio.h> 44#include <sys/sx.h> 45#include <sys/sysctl.h> 46#include <sys/syslog.h> 47#include <sys/systm.h> 48 49#include <net/bpf.h> 50#include <net/ethernet.h> 51#include <net/if.h> 52#include <net/if_var.h> 53#include <net/if_clone.h> 54#include <net/if_types.h> 55#include <net/netisr.h> 56#include <net/vnet.h> 57#include <net/route.h> 58 59#include <netinet/in.h> 60#include <netinet/in_systm.h> 61#include <netinet/in_var.h> 62#include <netinet/ip.h> 63#include <netinet/ip_var.h> 64#include <netinet/ip_encap.h> 65 66#include <machine/in_cksum.h> 67#include <security/mac/mac_framework.h> 68 69#define MEMTU 1500 70static const char mename[] = "me"; 71static MALLOC_DEFINE(M_IFME, mename, "Minimal Encapsulation for IP"); 72static VNET_DEFINE(struct mtx, me_mtx); 73#define V_me_mtx VNET(me_mtx) 74/* Minimal forwarding header RFC 2004 */ 75struct mobhdr { 76 uint8_t mob_proto; /* protocol */ 77 uint8_t mob_flags; /* flags */ 78#define MOB_FLAGS_SP 0x80 /* source present */ 79 uint16_t mob_csum; /* header checksum */ 80 struct in_addr mob_dst; /* original destination address */ 81 struct in_addr mob_src; /* original source addr (optional) */ 82} __packed; 83 84struct me_softc { 85 struct ifnet *me_ifp; 86 LIST_ENTRY(me_softc) me_list; 87 struct rmlock me_lock; 88 u_int me_fibnum; 89 const struct encaptab *me_ecookie; 90 struct in_addr me_src; 91 struct in_addr me_dst; 92}; 93#define ME2IFP(sc) ((sc)->me_ifp) 94#define ME_READY(sc) ((sc)->me_src.s_addr != 0) 95#define ME_LOCK_INIT(sc) rm_init(&(sc)->me_lock, "me softc") 96#define ME_LOCK_DESTROY(sc) rm_destroy(&(sc)->me_lock) 97#define ME_RLOCK_TRACKER struct rm_priotracker me_tracker 98#define ME_RLOCK(sc) rm_rlock(&(sc)->me_lock, &me_tracker) 99#define ME_RUNLOCK(sc) rm_runlock(&(sc)->me_lock, &me_tracker) 100#define ME_RLOCK_ASSERT(sc) rm_assert(&(sc)->me_lock, RA_RLOCKED) 101#define ME_WLOCK(sc) rm_wlock(&(sc)->me_lock) 102#define ME_WUNLOCK(sc) rm_wunlock(&(sc)->me_lock) 103#define ME_WLOCK_ASSERT(sc) rm_assert(&(sc)->me_lock, RA_WLOCKED) 104 105#define ME_LIST_LOCK_INIT(x) mtx_init(&V_me_mtx, "me_mtx", NULL, MTX_DEF) 106#define ME_LIST_LOCK_DESTROY(x) mtx_destroy(&V_me_mtx) 107#define ME_LIST_LOCK(x) mtx_lock(&V_me_mtx) 108#define ME_LIST_UNLOCK(x) mtx_unlock(&V_me_mtx) 109 110static VNET_DEFINE(LIST_HEAD(, me_softc), me_softc_list); 111#define V_me_softc_list VNET(me_softc_list) 112static struct sx me_ioctl_sx; 113SX_SYSINIT(me_ioctl_sx, &me_ioctl_sx, "me_ioctl"); 114 115static int me_clone_create(struct if_clone *, int, caddr_t); 116static void me_clone_destroy(struct ifnet *); 117static VNET_DEFINE(struct if_clone *, me_cloner); 118#define V_me_cloner VNET(me_cloner) 119 120static void me_qflush(struct ifnet *); 121static int me_transmit(struct ifnet *, struct mbuf *); 122static int me_ioctl(struct ifnet *, u_long, caddr_t); 123static int me_output(struct ifnet *, struct mbuf *, 124 const struct sockaddr *, struct route *); 125static int me_input(struct mbuf **, int *, int); 126 127static int me_set_tunnel(struct ifnet *, struct sockaddr_in *, 128 struct sockaddr_in *); 129static void me_delete_tunnel(struct ifnet *); 130 131SYSCTL_DECL(_net_link); 132static SYSCTL_NODE(_net_link, IFT_TUNNEL, me, CTLFLAG_RW, 0, 133 "Minimal Encapsulation for IP (RFC 2004)"); 134#ifndef MAX_ME_NEST 135#define MAX_ME_NEST 1 136#endif 137 138static VNET_DEFINE(int, max_me_nesting) = MAX_ME_NEST; 139#define V_max_me_nesting VNET(max_me_nesting) 140SYSCTL_INT(_net_link_me, OID_AUTO, max_nesting, CTLFLAG_RW | CTLFLAG_VNET, 141 &VNET_NAME(max_me_nesting), 0, "Max nested tunnels"); 142 143extern struct domain inetdomain; 144static void me_input10(struct mbuf *, int); 145static const struct protosw in_mobile_protosw = { 146 .pr_type = SOCK_RAW, 147 .pr_domain = &inetdomain, 148 .pr_protocol = IPPROTO_MOBILE, 149 .pr_flags = PR_ATOMIC|PR_ADDR, 150 .pr_input = me_input10, 151 .pr_output = (pr_output_t *)rip_output, 152 .pr_ctlinput = rip_ctlinput, 153 .pr_ctloutput = rip_ctloutput, 154 .pr_usrreqs = &rip_usrreqs 155}; 156 157static void 158vnet_me_init(const void *unused __unused) 159{ 160 LIST_INIT(&V_me_softc_list); 161 ME_LIST_LOCK_INIT(); 162 V_me_cloner = if_clone_simple(mename, me_clone_create, 163 me_clone_destroy, 0); 164} 165VNET_SYSINIT(vnet_me_init, SI_SUB_PROTO_IFATTACHDOMAIN, SI_ORDER_ANY, 166 vnet_me_init, NULL); 167 168static void 169vnet_me_uninit(const void *unused __unused) 170{ 171 172 if_clone_detach(V_me_cloner); 173 ME_LIST_LOCK_DESTROY(); 174} 175VNET_SYSUNINIT(vnet_me_uninit, SI_SUB_PROTO_IFATTACHDOMAIN, SI_ORDER_ANY, 176 vnet_me_uninit, NULL); 177 178static int 179me_clone_create(struct if_clone *ifc, int unit, caddr_t params) 180{ 181 struct me_softc *sc; 182 183 sc = malloc(sizeof(struct me_softc), M_IFME, M_WAITOK | M_ZERO); 184 sc->me_fibnum = curthread->td_proc->p_fibnum; 185 ME2IFP(sc) = if_alloc(IFT_TUNNEL); 186 ME_LOCK_INIT(sc); 187 ME2IFP(sc)->if_softc = sc; 188 if_initname(ME2IFP(sc), mename, unit); 189 190 ME2IFP(sc)->if_mtu = MEMTU - sizeof(struct mobhdr); 191 ME2IFP(sc)->if_flags = IFF_POINTOPOINT|IFF_MULTICAST; 192 ME2IFP(sc)->if_output = me_output; 193 ME2IFP(sc)->if_ioctl = me_ioctl; 194 ME2IFP(sc)->if_transmit = me_transmit; 195 ME2IFP(sc)->if_qflush = me_qflush; 196 if_attach(ME2IFP(sc)); 197 bpfattach(ME2IFP(sc), DLT_NULL, sizeof(u_int32_t)); 198 ME_LIST_LOCK(); 199 LIST_INSERT_HEAD(&V_me_softc_list, sc, me_list); 200 ME_LIST_UNLOCK(); 201 return (0); 202} 203 204static void 205me_clone_destroy(struct ifnet *ifp) 206{ 207 struct me_softc *sc; 208 209 sx_xlock(&me_ioctl_sx); 210 sc = ifp->if_softc; 211 me_delete_tunnel(ifp); 212 ME_LIST_LOCK(); 213 LIST_REMOVE(sc, me_list); 214 ME_LIST_UNLOCK(); 215 bpfdetach(ifp); 216 if_detach(ifp); 217 ifp->if_softc = NULL; 218 sx_xunlock(&me_ioctl_sx); 219 220 if_free(ifp); 221 ME_LOCK_DESTROY(sc); 222 free(sc, M_IFME); 223} 224 225static int 226me_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data) 227{ 228 ME_RLOCK_TRACKER; 229 struct ifreq *ifr = (struct ifreq *)data; 230 struct sockaddr_in *src, *dst; 231 struct me_softc *sc; 232 int error; 233 234 switch (cmd) { 235 case SIOCSIFMTU: 236 if (ifr->ifr_mtu < 576) 237 return (EINVAL); 238 ifp->if_mtu = ifr->ifr_mtu - sizeof(struct mobhdr); 239 return (0); 240 case SIOCSIFADDR: 241 ifp->if_flags |= IFF_UP; 242 case SIOCSIFFLAGS: 243 case SIOCADDMULTI: 244 case SIOCDELMULTI: 245 return (0); 246 } 247 sx_xlock(&me_ioctl_sx); 248 sc = ifp->if_softc; 249 if (sc == NULL) { 250 error = ENXIO; 251 goto end; 252 } 253 error = 0; 254 switch (cmd) { 255 case SIOCSIFPHYADDR: 256 src = (struct sockaddr_in *) 257 &(((struct in_aliasreq *)data)->ifra_addr); 258 dst = (struct sockaddr_in *) 259 &(((struct in_aliasreq *)data)->ifra_dstaddr); 260 if (src->sin_family != dst->sin_family || 261 src->sin_family != AF_INET || 262 src->sin_len != dst->sin_len || 263 src->sin_len != sizeof(struct sockaddr_in)) { 264 error = EINVAL; 265 break; 266 } 267 if (src->sin_addr.s_addr == INADDR_ANY || 268 dst->sin_addr.s_addr == INADDR_ANY) { 269 error = EADDRNOTAVAIL; 270 break; 271 } 272 error = me_set_tunnel(ifp, src, dst); 273 break; 274 case SIOCDIFPHYADDR: 275 me_delete_tunnel(ifp); 276 break; 277 case SIOCGIFPSRCADDR: 278 case SIOCGIFPDSTADDR: 279 ME_RLOCK(sc); 280 if (!ME_READY(sc)) { 281 error = EADDRNOTAVAIL; 282 ME_RUNLOCK(sc); 283 break; 284 } 285 src = (struct sockaddr_in *)&ifr->ifr_addr; 286 memset(src, 0, sizeof(*src)); 287 src->sin_family = AF_INET; 288 src->sin_len = sizeof(*src); 289 switch (cmd) { 290 case SIOCGIFPSRCADDR: 291 src->sin_addr = sc->me_src; 292 break; 293 case SIOCGIFPDSTADDR: 294 src->sin_addr = sc->me_dst; 295 break; 296 } 297 ME_RUNLOCK(sc); 298 error = prison_if(curthread->td_ucred, sintosa(src)); 299 if (error != 0) 300 memset(src, 0, sizeof(*src)); 301 break; 302 case SIOCGTUNFIB: 303 ifr->ifr_fib = sc->me_fibnum; 304 break; 305 case SIOCSTUNFIB: 306 if ((error = priv_check(curthread, PRIV_NET_GRE)) != 0) 307 break; 308 if (ifr->ifr_fib >= rt_numfibs) 309 error = EINVAL; 310 else 311 sc->me_fibnum = ifr->ifr_fib; 312 break; 313 default: 314 error = EINVAL; 315 break; 316 } 317end: 318 sx_xunlock(&me_ioctl_sx); 319 return (error); 320} 321 322static int 323me_encapcheck(const struct mbuf *m, int off, int proto, void *arg) 324{ 325 ME_RLOCK_TRACKER; 326 struct me_softc *sc; 327 struct ip *ip; 328 int ret; 329 330 sc = (struct me_softc *)arg; 331 if ((ME2IFP(sc)->if_flags & IFF_UP) == 0) 332 return (0); 333 334 M_ASSERTPKTHDR(m); 335 336 if (m->m_pkthdr.len < sizeof(struct ip) + sizeof(struct mobhdr) - 337 sizeof(struct in_addr)) 338 return (0); 339 340 ret = 0; 341 ME_RLOCK(sc); 342 if (ME_READY(sc)) { 343 ip = mtod(m, struct ip *); 344 if (sc->me_src.s_addr == ip->ip_dst.s_addr && 345 sc->me_dst.s_addr == ip->ip_src.s_addr) 346 ret = 32 * 2; 347 } 348 ME_RUNLOCK(sc); 349 return (ret); 350} 351 352static int 353me_set_tunnel(struct ifnet *ifp, struct sockaddr_in *src, 354 struct sockaddr_in *dst) 355{ 356 struct me_softc *sc, *tsc; 357 358 sx_assert(&me_ioctl_sx, SA_XLOCKED); 359 ME_LIST_LOCK(); 360 sc = ifp->if_softc; 361 LIST_FOREACH(tsc, &V_me_softc_list, me_list) { 362 if (tsc == sc || !ME_READY(tsc)) 363 continue; 364 if (tsc->me_src.s_addr == src->sin_addr.s_addr && 365 tsc->me_dst.s_addr == dst->sin_addr.s_addr) { 366 ME_LIST_UNLOCK(); 367 return (EADDRNOTAVAIL); 368 } 369 } 370 ME_LIST_UNLOCK(); 371 372 ME_WLOCK(sc); 373 sc->me_dst = dst->sin_addr; 374 sc->me_src = src->sin_addr; 375 ME_WUNLOCK(sc); 376 377 if (sc->me_ecookie == NULL) 378 sc->me_ecookie = encap_attach_func(AF_INET, IPPROTO_MOBILE, 379 me_encapcheck, &in_mobile_protosw, sc); 380 if (sc->me_ecookie != NULL) 381 ifp->if_drv_flags |= IFF_DRV_RUNNING; 382 return (0); 383} 384 385static void 386me_delete_tunnel(struct ifnet *ifp) 387{ 388 struct me_softc *sc = ifp->if_softc; 389 390 sx_assert(&me_ioctl_sx, SA_XLOCKED); 391 if (sc->me_ecookie != NULL) 392 encap_detach(sc->me_ecookie); 393 sc->me_ecookie = NULL; 394 ME_WLOCK(sc); 395 sc->me_src.s_addr = 0; 396 sc->me_dst.s_addr = 0; 397 ME_WUNLOCK(sc); 398 ifp->if_drv_flags &= ~IFF_DRV_RUNNING; 399} 400 401static uint16_t 402me_in_cksum(uint16_t *p, int nwords) 403{ 404 uint32_t sum = 0; 405 406 while (nwords-- > 0) 407 sum += *p++; 408 sum = (sum >> 16) + (sum & 0xffff); 409 sum += (sum >> 16); 410 return (~sum); 411} 412 413static void 414me_input10(struct mbuf *m, int off) 415{ 416 int proto; 417 418 proto = (mtod(m, struct ip *))->ip_p; 419 me_input(&m, &off, proto); 420} 421 422int 423me_input(struct mbuf **mp, int *offp, int proto) 424{ 425 struct me_softc *sc; 426 struct mobhdr *mh; 427 struct ifnet *ifp; 428 struct mbuf *m; 429 struct ip *ip; 430 int hlen; 431 432 m = *mp; 433 sc = encap_getarg(m); 434 KASSERT(sc != NULL, ("encap_getarg returned NULL")); 435 436 ifp = ME2IFP(sc); 437 /* checks for short packets */ 438 hlen = sizeof(struct mobhdr); 439 if (m->m_pkthdr.len < sizeof(struct ip) + hlen) 440 hlen -= sizeof(struct in_addr); 441 if (m->m_len < sizeof(struct ip) + hlen) 442 m = m_pullup(m, sizeof(struct ip) + hlen); 443 if (m == NULL) 444 goto drop; 445 mh = (struct mobhdr *)mtodo(m, sizeof(struct ip)); 446 /* check for wrong flags */ 447 if (mh->mob_flags & (~MOB_FLAGS_SP)) { 448 m_freem(m); 449 goto drop; 450 } 451 if (mh->mob_flags) { 452 if (hlen != sizeof(struct mobhdr)) { 453 m_freem(m); 454 goto drop; 455 } 456 } else 457 hlen = sizeof(struct mobhdr) - sizeof(struct in_addr); 458 /* check mobile header checksum */ 459 if (me_in_cksum((uint16_t *)mh, hlen / sizeof(uint16_t)) != 0) { 460 m_freem(m); 461 goto drop; 462 } 463#ifdef MAC 464 mac_ifnet_create_mbuf(ifp, m); 465#endif 466 ip = mtod(m, struct ip *); 467 ip->ip_dst = mh->mob_dst; 468 ip->ip_p = mh->mob_proto; 469 ip->ip_sum = 0; 470 ip->ip_len = htons(m->m_pkthdr.len - hlen); 471 if (mh->mob_flags) 472 ip->ip_src = mh->mob_src; 473 memmove(mtodo(m, hlen), ip, sizeof(struct ip)); 474 m_adj(m, hlen); 475 m_clrprotoflags(m); 476 m->m_pkthdr.rcvif = ifp; 477 m->m_pkthdr.csum_flags |= (CSUM_IP_CHECKED | CSUM_IP_VALID); 478 M_SETFIB(m, ifp->if_fib); 479 hlen = AF_INET; 480 BPF_MTAP2(ifp, &hlen, sizeof(hlen), m); 481 if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1); 482 if_inc_counter(ifp, IFCOUNTER_IBYTES, m->m_pkthdr.len); 483 if ((ifp->if_flags & IFF_MONITOR) != 0) 484 m_freem(m); 485 else 486 netisr_dispatch(NETISR_IP, m); 487 return (IPPROTO_DONE); 488drop: 489 if_inc_counter(ifp, IFCOUNTER_IERRORS, 1); 490 return (IPPROTO_DONE); 491} 492 493#define MTAG_ME 1414491977 494static int 495me_check_nesting(struct ifnet *ifp, struct mbuf *m) 496{ 497 struct m_tag *mtag; 498 int count; 499 500 count = 1; 501 mtag = NULL; 502 while ((mtag = m_tag_locate(m, MTAG_ME, 0, mtag)) != NULL) { 503 if (*(struct ifnet **)(mtag + 1) == ifp) { 504 log(LOG_NOTICE, "%s: loop detected\n", ifp->if_xname); 505 return (EIO); 506 } 507 count++; 508 } 509 if (count > V_max_me_nesting) { 510 log(LOG_NOTICE, 511 "%s: if_output recursively called too many times(%d)\n", 512 ifp->if_xname, count); 513 return (EIO); 514 } 515 mtag = m_tag_alloc(MTAG_ME, 0, sizeof(struct ifnet *), M_NOWAIT); 516 if (mtag == NULL) 517 return (ENOMEM); 518 *(struct ifnet **)(mtag + 1) = ifp; 519 m_tag_prepend(m, mtag); 520 return (0); 521} 522 523static int 524me_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst, 525 struct route *ro) 526{ 527 uint32_t af; 528 int error; 529 530#ifdef MAC 531 error = mac_ifnet_check_transmit(ifp, m); 532 if (error != 0) 533 goto drop; 534#endif 535 if ((ifp->if_flags & IFF_MONITOR) != 0 || 536 (ifp->if_flags & IFF_UP) == 0) { 537 error = ENETDOWN; 538 goto drop; 539 } 540 541 error = me_check_nesting(ifp, m); 542 if (error != 0) 543 goto drop; 544 545 m->m_flags &= ~(M_BCAST|M_MCAST); 546 if (dst->sa_family == AF_UNSPEC) 547 bcopy(dst->sa_data, &af, sizeof(af)); 548 else 549 af = dst->sa_family; 550 if (af != AF_INET) { 551 error = EAFNOSUPPORT; 552 goto drop; 553 } 554 BPF_MTAP2(ifp, &af, sizeof(af), m); 555 return (ifp->if_transmit(ifp, m)); 556drop: 557 m_freem(m); 558 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 559 return (error); 560} 561 562static int 563me_transmit(struct ifnet *ifp, struct mbuf *m) 564{ 565 ME_RLOCK_TRACKER; 566 struct mobhdr mh; 567 struct me_softc *sc; 568 struct ip *ip; 569 int error, hlen, plen; 570 571 sc = ifp->if_softc; 572 if (sc == NULL) { 573 error = ENETDOWN; 574 m_freem(m); 575 goto drop; 576 } 577 if (m->m_len < sizeof(struct ip)) 578 m = m_pullup(m, sizeof(struct ip)); 579 if (m == NULL) { 580 error = ENOBUFS; 581 goto drop; 582 } 583 ip = mtod(m, struct ip *); 584 /* Fragmented datagramms shouldn't be encapsulated */ 585 if (ip->ip_off & htons(IP_MF | IP_OFFMASK)) { 586 error = EINVAL; 587 m_freem(m); 588 goto drop; 589 } 590 mh.mob_proto = ip->ip_p; 591 mh.mob_src = ip->ip_src; 592 mh.mob_dst = ip->ip_dst; 593 ME_RLOCK(sc); 594 if (!ME_READY(sc)) { 595 ME_RUNLOCK(sc); 596 error = ENETDOWN; 597 m_freem(m); 598 goto drop; 599 } 600 if (in_hosteq(sc->me_src, ip->ip_src)) { 601 hlen = sizeof(struct mobhdr) - sizeof(struct in_addr); 602 mh.mob_flags = 0; 603 } else { 604 hlen = sizeof(struct mobhdr); 605 mh.mob_flags = MOB_FLAGS_SP; 606 } 607 plen = m->m_pkthdr.len; 608 ip->ip_src = sc->me_src; 609 ip->ip_dst = sc->me_dst; 610 M_SETFIB(m, sc->me_fibnum); 611 ME_RUNLOCK(sc); 612 M_PREPEND(m, hlen, M_NOWAIT); 613 if (m == NULL) { 614 error = ENOBUFS; 615 goto drop; 616 } 617 if (m->m_len < sizeof(struct ip) + hlen) 618 m = m_pullup(m, sizeof(struct ip) + hlen); 619 if (m == NULL) { 620 error = ENOBUFS; 621 goto drop; 622 } 623 memmove(mtod(m, void *), mtodo(m, hlen), sizeof(struct ip)); 624 ip = mtod(m, struct ip *); 625 ip->ip_len = htons(m->m_pkthdr.len); 626 ip->ip_p = IPPROTO_MOBILE; 627 ip->ip_sum = 0; 628 mh.mob_csum = 0; 629 mh.mob_csum = me_in_cksum((uint16_t *)&mh, hlen / sizeof(uint16_t)); 630 bcopy(&mh, mtodo(m, sizeof(struct ip)), hlen); 631 error = ip_output(m, NULL, NULL, IP_FORWARDING, NULL, NULL); 632drop: 633 if (error) 634 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 635 else { 636 if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1); 637 if_inc_counter(ifp, IFCOUNTER_OBYTES, plen); 638 } 639 return (error); 640} 641 642static void 643me_qflush(struct ifnet *ifp __unused) 644{ 645 646} 647 648static int 649memodevent(module_t mod, int type, void *data) 650{ 651 652 switch (type) { 653 case MOD_LOAD: 654 case MOD_UNLOAD: 655 break; 656 default: 657 return (EOPNOTSUPP); 658 } 659 return (0); 660} 661 662static moduledata_t me_mod = { 663 "if_me", 664 memodevent, 665 0 666}; 667 668DECLARE_MODULE(if_me, me_mod, SI_SUB_PSEUDO, SI_ORDER_ANY); 669MODULE_VERSION(if_me, 1); 670