1 /* $NetBSD: link_proto.c,v 1.39 2019/09/25 09:53:37 ozaki-r Exp $ */ 2 3 /*- 4 * Copyright (c) 1982, 1986, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * @(#)uipc_proto.c 8.2 (Berkeley) 2/14/95 32 */ 33 34 #include <sys/cdefs.h> 35 __KERNEL_RCSID(0, "$NetBSD: link_proto.c,v 1.39 2019/09/25 09:53:37 ozaki-r Exp $"); 36 37 #include <sys/param.h> 38 #include <sys/socket.h> 39 #include <sys/protosw.h> 40 #include <sys/domain.h> 41 #include <sys/mbuf.h> 42 #include <sys/un.h> 43 #include <sys/socketvar.h> 44 45 #include <net/if.h> 46 #include <net/if_dl.h> 47 #include <net/raw_cb.h> 48 #include <net/route.h> 49 50 static int sockaddr_dl_cmp(const struct sockaddr *, const struct sockaddr *); 51 static int link_attach(struct socket *, int); 52 static void link_detach(struct socket *); 53 static int link_accept(struct socket *, struct sockaddr *); 54 static int link_bind(struct socket *, struct sockaddr *, struct lwp *); 55 static int link_listen(struct socket *, struct lwp *); 56 static int link_connect(struct socket *, struct sockaddr *, struct lwp *); 57 static int link_connect2(struct socket *, struct socket *); 58 static int link_disconnect(struct socket *); 59 static int link_shutdown(struct socket *); 60 static int link_abort(struct socket *); 61 static int link_ioctl(struct socket *, u_long, void *, struct ifnet *); 62 static int link_stat(struct socket *, struct stat *); 63 static int link_peeraddr(struct socket *, struct sockaddr *); 64 static int link_sockaddr(struct socket *, struct sockaddr *); 65 static int link_rcvd(struct socket *, int, struct lwp *); 66 static int link_recvoob(struct socket *, struct mbuf *, int); 67 static int link_send(struct socket *, struct mbuf *, struct sockaddr *, 68 struct mbuf *, struct lwp *); 69 static int link_sendoob(struct socket *, struct mbuf *, struct mbuf *); 70 static int link_purgeif(struct socket *, struct ifnet *); 71 static void link_init(void); 72 73 /* 74 * Definitions of protocols supported in the link-layer domain. 75 */ 76 77 DOMAIN_DEFINE(linkdomain); /* forward define and add to link set */ 78 79 static const struct pr_usrreqs link_usrreqs = { 80 .pr_attach = link_attach, 81 .pr_detach = link_detach, 82 .pr_accept = link_accept, 83 .pr_bind = link_bind, 84 .pr_listen = link_listen, 85 .pr_connect = link_connect, 86 .pr_connect2 = link_connect2, 87 .pr_disconnect = link_disconnect, 88 .pr_shutdown = link_shutdown, 89 .pr_abort = link_abort, 90 .pr_ioctl = link_ioctl, 91 .pr_stat = link_stat, 92 .pr_peeraddr = link_peeraddr, 93 .pr_sockaddr = link_sockaddr, 94 .pr_rcvd = link_rcvd, 95 .pr_recvoob = link_recvoob, 96 .pr_send = link_send, 97 .pr_sendoob = link_sendoob, 98 .pr_purgeif = link_purgeif, 99 }; 100 101 const struct protosw linksw[] = { 102 { .pr_type = SOCK_DGRAM, 103 .pr_domain = &linkdomain, 104 .pr_protocol = 0, /* XXX */ 105 .pr_flags = PR_ATOMIC|PR_ADDR|PR_PURGEIF, 106 .pr_input = NULL, 107 .pr_ctlinput = NULL, 108 .pr_ctloutput = NULL, 109 .pr_usrreqs = &link_usrreqs, 110 .pr_init = link_init, 111 }, 112 }; 113 114 struct domain linkdomain = { 115 .dom_family = AF_LINK, 116 .dom_name = "link", 117 .dom_externalize = NULL, 118 .dom_dispose = NULL, 119 .dom_protosw = linksw, 120 .dom_protoswNPROTOSW = &linksw[__arraycount(linksw)], 121 .dom_sockaddr_cmp = sockaddr_dl_cmp 122 }; 123 124 static void 125 link_init(void) 126 { 127 return; 128 } 129 130 static int 131 link_control(struct socket *so, unsigned long cmd, void *data, 132 struct ifnet *ifp) 133 { 134 int error, s; 135 bool isactive, mkactive; 136 struct if_laddrreq *iflr; 137 union { 138 struct sockaddr sa; 139 struct sockaddr_dl sdl; 140 struct sockaddr_storage ss; 141 } u; 142 struct ifaddr *ifa; 143 const struct sockaddr_dl *asdl, *nsdl; 144 struct psref psref; 145 146 switch (cmd) { 147 case SIOCALIFADDR: 148 case SIOCDLIFADDR: 149 case SIOCGLIFADDR: 150 iflr = data; 151 152 if (iflr->addr.ss_family != AF_LINK) 153 return EINVAL; 154 155 asdl = satocsdl(sstocsa(&iflr->addr)); 156 157 if (asdl->sdl_alen != ifp->if_addrlen) 158 return EINVAL; 159 160 if (sockaddr_dl_init(&u.sdl, sizeof(u.ss), ifp->if_index, 161 ifp->if_type, ifp->if_xname, strlen(ifp->if_xname), 162 CLLADDR(asdl), asdl->sdl_alen) == NULL) 163 return EINVAL; 164 165 if ((iflr->flags & IFLR_PREFIX) == 0) 166 ; 167 else if (iflr->prefixlen != NBBY * ifp->if_addrlen) 168 return EINVAL; /* XXX match with prefix */ 169 170 error = 0; 171 172 s = pserialize_read_enter(); 173 IFADDR_READER_FOREACH(ifa, ifp) { 174 if (sockaddr_cmp(&u.sa, ifa->ifa_addr) == 0) { 175 ifa_acquire(ifa, &psref); 176 break; 177 } 178 } 179 pserialize_read_exit(s); 180 181 switch (cmd) { 182 case SIOCGLIFADDR: 183 ifa_release(ifa, &psref); 184 s = pserialize_read_enter(); 185 if ((iflr->flags & IFLR_PREFIX) == 0) { 186 IFADDR_READER_FOREACH(ifa, ifp) { 187 if (ifa->ifa_addr->sa_family == AF_LINK) 188 break; 189 } 190 } 191 if (ifa == NULL) { 192 pserialize_read_exit(s); 193 error = EADDRNOTAVAIL; 194 break; 195 } 196 197 if (ifa == ifp->if_dl) 198 iflr->flags = IFLR_ACTIVE; 199 else 200 iflr->flags = 0; 201 202 if (ifa == ifp->if_hwdl) 203 iflr->flags |= IFLR_FACTORY; 204 205 sockaddr_copy(sstosa(&iflr->addr), sizeof(iflr->addr), 206 ifa->ifa_addr); 207 pserialize_read_exit(s); 208 ifa = NULL; 209 210 break; 211 case SIOCDLIFADDR: 212 if (ifa == NULL) 213 error = EADDRNOTAVAIL; 214 else if (ifa == ifp->if_dl || ifa == ifp->if_hwdl) 215 error = EBUSY; 216 else { 217 /* TBD routing socket */ 218 rt_addrmsg(RTM_DELETE, ifa); 219 /* We need to release psref for ifa_remove */ 220 ifaref(ifa); 221 ifa_release(ifa, &psref); 222 ifa_remove(ifp, ifa); 223 KASSERTMSG(ifa->ifa_refcnt == 1, "ifa_refcnt=%d", 224 ifa->ifa_refcnt); 225 ifafree(ifa); 226 ifa = NULL; 227 } 228 break; 229 case SIOCALIFADDR: 230 if (ifa == NULL) { 231 ifa = if_dl_create(ifp, &nsdl); 232 if (ifa == NULL) { 233 error = ENOMEM; 234 break; 235 } 236 ifa_acquire(ifa, &psref); 237 sockaddr_copy(ifa->ifa_addr, 238 ifa->ifa_addr->sa_len, &u.sa); 239 ifa_insert(ifp, ifa); 240 rt_addrmsg(RTM_ADD, ifa); 241 } 242 243 mkactive = (iflr->flags & IFLR_ACTIVE) != 0; 244 isactive = (ifa == ifp->if_dl); 245 246 if (!isactive && mkactive) { 247 if_activate_sadl(ifp, ifa, nsdl); 248 rt_addrmsg(RTM_CHANGE, ifa); 249 error = ENETRESET; 250 } 251 break; 252 } 253 ifa_release(ifa, &psref); 254 if (error != ENETRESET) 255 return error; 256 else if ((ifp->if_flags & IFF_RUNNING) != 0 && 257 ifp->if_init != NULL) 258 return (*ifp->if_init)(ifp); 259 else 260 return 0; 261 default: 262 return ENOTTY; 263 } 264 } 265 266 static int 267 link_attach(struct socket *so, int proto) 268 { 269 sosetlock(so); 270 KASSERT(solocked(so)); 271 return 0; 272 } 273 274 static void 275 link_detach(struct socket *so) 276 { 277 KASSERT(solocked(so)); 278 sofree(so); 279 } 280 281 static int 282 link_accept(struct socket *so, struct sockaddr *nam) 283 { 284 KASSERT(solocked(so)); 285 286 return EOPNOTSUPP; 287 } 288 289 static int 290 link_bind(struct socket *so, struct sockaddr *nam, struct lwp *l) 291 { 292 KASSERT(solocked(so)); 293 294 return EOPNOTSUPP; 295 } 296 297 static int 298 link_listen(struct socket *so, struct lwp *l) 299 { 300 KASSERT(solocked(so)); 301 302 return EOPNOTSUPP; 303 } 304 305 static int 306 link_connect(struct socket *so, struct sockaddr *nam, struct lwp *l) 307 { 308 KASSERT(solocked(so)); 309 310 return EOPNOTSUPP; 311 } 312 313 static int 314 link_connect2(struct socket *so, struct socket *so2) 315 { 316 KASSERT(solocked(so)); 317 318 return EOPNOTSUPP; 319 } 320 321 static int 322 link_disconnect(struct socket *so) 323 { 324 KASSERT(solocked(so)); 325 326 return EOPNOTSUPP; 327 } 328 329 static int 330 link_shutdown(struct socket *so) 331 { 332 KASSERT(solocked(so)); 333 334 return EOPNOTSUPP; 335 } 336 337 static int 338 link_abort(struct socket *so) 339 { 340 KASSERT(solocked(so)); 341 342 return EOPNOTSUPP; 343 } 344 345 static int 346 link_ioctl(struct socket *so, u_long cmd, void *nam, struct ifnet *ifp) 347 { 348 return link_control(so, cmd, nam, ifp); 349 } 350 351 static int 352 link_stat(struct socket *so, struct stat *ub) 353 { 354 KASSERT(solocked(so)); 355 356 return 0; 357 } 358 359 static int 360 link_peeraddr(struct socket *so, struct sockaddr *nam) 361 { 362 KASSERT(solocked(so)); 363 364 return EOPNOTSUPP; 365 } 366 367 static int 368 link_sockaddr(struct socket *so, struct sockaddr *nam) 369 { 370 KASSERT(solocked(so)); 371 372 return EOPNOTSUPP; 373 } 374 375 static int 376 link_rcvd(struct socket *so, int flags, struct lwp *l) 377 { 378 KASSERT(solocked(so)); 379 380 return EOPNOTSUPP; 381 } 382 383 static int 384 link_recvoob(struct socket *so, struct mbuf *m, int flags) 385 { 386 KASSERT(solocked(so)); 387 388 return EOPNOTSUPP; 389 } 390 391 static int 392 link_send(struct socket *so, struct mbuf *m, struct sockaddr *nam, 393 struct mbuf *control, struct lwp *l) 394 { 395 KASSERT(solocked(so)); 396 397 return EOPNOTSUPP; 398 } 399 400 static int 401 link_sendoob(struct socket *so, struct mbuf *m, struct mbuf *control) 402 { 403 KASSERT(solocked(so)); 404 405 m_freem(m); 406 m_freem(control); 407 408 return EOPNOTSUPP; 409 } 410 411 static int 412 link_purgeif(struct socket *so, struct ifnet *ifp) 413 { 414 415 return EOPNOTSUPP; 416 } 417 418 /* Compare the field at byte offsets [fieldstart, fieldend) in 419 * two memory regions, [l, l + llen) and [r, r + llen). 420 */ 421 static inline int 422 submemcmp(const void *l, const void *r, 423 const uint_fast8_t llen, const uint_fast8_t rlen, 424 const uint_fast8_t fieldstart, const uint_fast8_t fieldend) 425 { 426 uint_fast8_t cmpend, minlen; 427 const uint8_t *lb = l, *rb = r; 428 int rc; 429 430 minlen = MIN(llen, rlen); 431 432 /* The field is missing from one region. The shorter region is the 433 * lesser region. 434 */ 435 if (fieldstart >= minlen) 436 return llen - rlen; 437 438 /* Two empty, present fields are always equal. */ 439 if (fieldstart > fieldend) 440 return 0; 441 442 cmpend = MIN(fieldend, minlen); 443 444 rc = memcmp(&lb[fieldstart], &rb[fieldstart], cmpend - fieldstart); 445 446 if (rc != 0) 447 return rc; 448 /* If one or both fields are truncated, then the shorter is the lesser 449 * field. 450 */ 451 if (minlen < fieldend) 452 return llen - rlen; 453 /* Fields are full-length and equal. The fields are equal. */ 454 return 0; 455 } 456 457 uint8_t 458 sockaddr_dl_measure(uint8_t namelen, uint8_t addrlen) 459 { 460 return offsetof(struct sockaddr_dl, sdl_data[namelen + addrlen]); 461 } 462 463 struct sockaddr * 464 sockaddr_dl_alloc(uint16_t ifindex, uint8_t type, 465 const void *name, uint8_t namelen, const void *addr, uint8_t addrlen, 466 int flags) 467 { 468 struct sockaddr *sa; 469 socklen_t len; 470 471 len = sockaddr_dl_measure(namelen, addrlen); 472 sa = sockaddr_alloc(AF_LINK, len, flags); 473 474 if (sa == NULL) 475 return NULL; 476 477 if (sockaddr_dl_init(satosdl(sa), len, ifindex, type, name, namelen, 478 addr, addrlen) == NULL) { 479 sockaddr_free(sa); 480 return NULL; 481 } 482 483 return sa; 484 } 485 486 struct sockaddr_dl * 487 sockaddr_dl_init(struct sockaddr_dl *sdl, socklen_t socklen, uint16_t ifindex, 488 uint8_t type, const void *name, uint8_t namelen, const void *addr, 489 uint8_t addrlen) 490 { 491 socklen_t len; 492 493 sdl->sdl_family = AF_LINK; 494 sdl->sdl_slen = 0; 495 len = sockaddr_dl_measure(namelen, addrlen); 496 if (len > socklen) { 497 sdl->sdl_len = socklen; 498 #ifdef DIAGNOSTIC 499 printf("%s: too long: %u > %u\n", __func__, (u_int)len, 500 (u_int)socklen); 501 #endif 502 return NULL; 503 } 504 sdl->sdl_len = len; 505 sdl->sdl_index = ifindex; 506 sdl->sdl_type = type; 507 memset(&sdl->sdl_data[0], 0, namelen + addrlen); 508 if (name != NULL) { 509 memcpy(&sdl->sdl_data[0], name, namelen); 510 sdl->sdl_nlen = namelen; 511 } else 512 sdl->sdl_nlen = 0; 513 if (addr != NULL) { 514 memcpy(&sdl->sdl_data[sdl->sdl_nlen], addr, addrlen); 515 sdl->sdl_alen = addrlen; 516 } else 517 sdl->sdl_alen = 0; 518 return sdl; 519 } 520 521 static int 522 sockaddr_dl_cmp(const struct sockaddr *sa1, const struct sockaddr *sa2) 523 { 524 int rc; 525 const uint_fast8_t indexofs = offsetof(struct sockaddr_dl, sdl_index); 526 const uint_fast8_t nlenofs = offsetof(struct sockaddr_dl, sdl_nlen); 527 uint_fast8_t dataofs = offsetof(struct sockaddr_dl, sdl_data[0]); 528 const struct sockaddr_dl *sdl1, *sdl2; 529 530 sdl1 = satocsdl(sa1); 531 sdl2 = satocsdl(sa2); 532 533 rc = submemcmp(sdl1, sdl2, sdl1->sdl_len, sdl2->sdl_len, 534 indexofs, nlenofs); 535 536 if (rc != 0) 537 return rc; 538 539 rc = submemcmp(sdl1, sdl2, sdl1->sdl_len, sdl2->sdl_len, 540 dataofs, dataofs + MIN(sdl1->sdl_nlen, sdl2->sdl_nlen)); 541 542 if (rc != 0) 543 return rc; 544 545 if (sdl1->sdl_nlen != sdl2->sdl_nlen) 546 return sdl1->sdl_nlen - sdl2->sdl_nlen; 547 548 dataofs += sdl1->sdl_nlen; 549 550 rc = submemcmp(sdl1, sdl2, sdl1->sdl_len, sdl2->sdl_len, 551 dataofs, dataofs + MIN(sdl1->sdl_alen, sdl2->sdl_alen)); 552 553 if (rc != 0) 554 return rc; 555 556 if (sdl1->sdl_alen != sdl2->sdl_alen) 557 return sdl1->sdl_alen - sdl2->sdl_alen; 558 559 dataofs += sdl1->sdl_alen; 560 561 rc = submemcmp(sdl1, sdl2, sdl1->sdl_len, sdl2->sdl_len, 562 dataofs, dataofs + MIN(sdl1->sdl_slen, sdl2->sdl_slen)); 563 564 if (sdl1->sdl_slen != sdl2->sdl_slen) 565 return sdl1->sdl_slen - sdl2->sdl_slen; 566 567 return sdl1->sdl_len - sdl2->sdl_len; 568 } 569 570 struct sockaddr_dl * 571 sockaddr_dl_setaddr(struct sockaddr_dl *sdl, socklen_t socklen, 572 const void *addr, uint8_t addrlen) 573 { 574 socklen_t len; 575 576 len = sockaddr_dl_measure(sdl->sdl_nlen, addrlen); 577 if (len > socklen) { 578 #ifdef DIAGNOSTIC 579 printf("%s: too long: %u > %u\n", __func__, (u_int)len, 580 (u_int)socklen); 581 #endif 582 return NULL; 583 } 584 memcpy(&sdl->sdl_data[sdl->sdl_nlen], addr, addrlen); 585 sdl->sdl_alen = addrlen; 586 sdl->sdl_len = len; 587 return sdl; 588 } 589