1 /* $NetBSD: link_proto.c,v 1.41 2025/06/05 06:29:27 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 1.41 2025/06/05 06:29:27 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 ifa = if_first_addr(ifp, AF_LINK); 187 if (ifa == NULL) { 188 pserialize_read_exit(s); 189 error = EADDRNOTAVAIL; 190 break; 191 } 192 193 if (ifa == ifp->if_dl) 194 iflr->flags = IFLR_ACTIVE; 195 else 196 iflr->flags = 0; 197 198 if (ifa == ifp->if_hwdl) 199 iflr->flags |= IFLR_FACTORY; 200 201 sockaddr_copy(sstosa(&iflr->addr), sizeof(iflr->addr), 202 ifa->ifa_addr); 203 pserialize_read_exit(s); 204 ifa = NULL; 205 206 break; 207 case SIOCDLIFADDR: 208 if (ifa == NULL) 209 error = EADDRNOTAVAIL; 210 else if (ifa == ifp->if_dl || ifa == ifp->if_hwdl) 211 error = EBUSY; 212 else { 213 /* TBD routing socket */ 214 rt_addrmsg(RTM_DELETE, ifa); 215 /* We need to release psref for ifa_remove */ 216 ifaref(ifa); 217 ifa_release(ifa, &psref); 218 ifa_remove(ifp, ifa); 219 KASSERTMSG(ifa->ifa_refcnt == 1, "ifa_refcnt=%d", 220 ifa->ifa_refcnt); 221 ifafree(ifa); 222 ifa = NULL; 223 } 224 break; 225 case SIOCALIFADDR: 226 if (ifa == NULL) { 227 ifa = if_dl_create(ifp, &nsdl); 228 if (ifa == NULL) { 229 error = ENOMEM; 230 break; 231 } 232 ifa_acquire(ifa, &psref); 233 sockaddr_copy(ifa->ifa_addr, 234 ifa->ifa_addr->sa_len, &u.sa); 235 ifa_insert(ifp, ifa); 236 rt_addrmsg(RTM_ADD, ifa); 237 } 238 239 mkactive = (iflr->flags & IFLR_ACTIVE) != 0; 240 isactive = (ifa == ifp->if_dl); 241 242 if (!isactive && mkactive) { 243 if_activate_sadl(ifp, ifa, nsdl); 244 rt_addrmsg(RTM_CHANGE, ifa); 245 error = ENETRESET; 246 } 247 break; 248 } 249 ifa_release(ifa, &psref); 250 if (error != ENETRESET) 251 return error; 252 else if ((ifp->if_flags & IFF_RUNNING) != 0 && 253 ifp->if_init != NULL) 254 return if_init(ifp); 255 else 256 return 0; 257 default: 258 return ENOTTY; 259 } 260 } 261 262 static int 263 link_attach(struct socket *so, int proto) 264 { 265 sosetlock(so); 266 KASSERT(solocked(so)); 267 return 0; 268 } 269 270 static void 271 link_detach(struct socket *so) 272 { 273 KASSERT(solocked(so)); 274 sofree(so); 275 } 276 277 static int 278 link_accept(struct socket *so, struct sockaddr *nam) 279 { 280 KASSERT(solocked(so)); 281 282 return EOPNOTSUPP; 283 } 284 285 static int 286 link_bind(struct socket *so, struct sockaddr *nam, struct lwp *l) 287 { 288 KASSERT(solocked(so)); 289 290 return EOPNOTSUPP; 291 } 292 293 static int 294 link_listen(struct socket *so, struct lwp *l) 295 { 296 KASSERT(solocked(so)); 297 298 return EOPNOTSUPP; 299 } 300 301 static int 302 link_connect(struct socket *so, struct sockaddr *nam, struct lwp *l) 303 { 304 KASSERT(solocked(so)); 305 306 return EOPNOTSUPP; 307 } 308 309 static int 310 link_connect2(struct socket *so, struct socket *so2) 311 { 312 KASSERT(solocked(so)); 313 314 return EOPNOTSUPP; 315 } 316 317 static int 318 link_disconnect(struct socket *so) 319 { 320 KASSERT(solocked(so)); 321 322 return EOPNOTSUPP; 323 } 324 325 static int 326 link_shutdown(struct socket *so) 327 { 328 KASSERT(solocked(so)); 329 330 return EOPNOTSUPP; 331 } 332 333 static int 334 link_abort(struct socket *so) 335 { 336 KASSERT(solocked(so)); 337 338 return EOPNOTSUPP; 339 } 340 341 static int 342 link_ioctl(struct socket *so, u_long cmd, void *nam, struct ifnet *ifp) 343 { 344 return link_control(so, cmd, nam, ifp); 345 } 346 347 static int 348 link_stat(struct socket *so, struct stat *ub) 349 { 350 KASSERT(solocked(so)); 351 352 return 0; 353 } 354 355 static int 356 link_peeraddr(struct socket *so, struct sockaddr *nam) 357 { 358 KASSERT(solocked(so)); 359 360 return EOPNOTSUPP; 361 } 362 363 static int 364 link_sockaddr(struct socket *so, struct sockaddr *nam) 365 { 366 KASSERT(solocked(so)); 367 368 return EOPNOTSUPP; 369 } 370 371 static int 372 link_rcvd(struct socket *so, int flags, struct lwp *l) 373 { 374 KASSERT(solocked(so)); 375 376 return EOPNOTSUPP; 377 } 378 379 static int 380 link_recvoob(struct socket *so, struct mbuf *m, int flags) 381 { 382 KASSERT(solocked(so)); 383 384 return EOPNOTSUPP; 385 } 386 387 static int 388 link_send(struct socket *so, struct mbuf *m, struct sockaddr *nam, 389 struct mbuf *control, struct lwp *l) 390 { 391 KASSERT(solocked(so)); 392 393 return EOPNOTSUPP; 394 } 395 396 static int 397 link_sendoob(struct socket *so, struct mbuf *m, struct mbuf *control) 398 { 399 KASSERT(solocked(so)); 400 401 m_freem(m); 402 m_freem(control); 403 404 return EOPNOTSUPP; 405 } 406 407 static int 408 link_purgeif(struct socket *so, struct ifnet *ifp) 409 { 410 411 return EOPNOTSUPP; 412 } 413 414 /* Compare the field at byte offsets [fieldstart, fieldend) in 415 * two memory regions, [l, l + llen) and [r, r + llen). 416 */ 417 static inline int 418 submemcmp(const void *l, const void *r, 419 const uint_fast8_t llen, const uint_fast8_t rlen, 420 const uint_fast8_t fieldstart, const uint_fast8_t fieldend) 421 { 422 uint_fast8_t cmpend, minlen; 423 const uint8_t *lb = l, *rb = r; 424 int rc; 425 426 minlen = MIN(llen, rlen); 427 428 /* The field is missing from one region. The shorter region is the 429 * lesser region. 430 */ 431 if (fieldstart >= minlen) 432 return llen - rlen; 433 434 /* Two empty, present fields are always equal. */ 435 if (fieldstart > fieldend) 436 return 0; 437 438 cmpend = MIN(fieldend, minlen); 439 440 rc = memcmp(&lb[fieldstart], &rb[fieldstart], cmpend - fieldstart); 441 442 if (rc != 0) 443 return rc; 444 /* If one or both fields are truncated, then the shorter is the lesser 445 * field. 446 */ 447 if (minlen < fieldend) 448 return llen - rlen; 449 /* Fields are full-length and equal. The fields are equal. */ 450 return 0; 451 } 452 453 uint8_t 454 sockaddr_dl_measure(uint8_t namelen, uint8_t addrlen) 455 { 456 return offsetof(struct sockaddr_dl, sdl_data[namelen + addrlen]); 457 } 458 459 struct sockaddr * 460 sockaddr_dl_alloc(uint16_t ifindex, uint8_t type, 461 const void *name, uint8_t namelen, const void *addr, uint8_t addrlen, 462 int flags) 463 { 464 struct sockaddr *sa; 465 socklen_t len; 466 467 len = sockaddr_dl_measure(namelen, addrlen); 468 sa = sockaddr_alloc(AF_LINK, len, flags); 469 470 if (sa == NULL) 471 return NULL; 472 473 if (sockaddr_dl_init(satosdl(sa), len, ifindex, type, name, namelen, 474 addr, addrlen) == NULL) { 475 sockaddr_free(sa); 476 return NULL; 477 } 478 479 return sa; 480 } 481 482 struct sockaddr_dl * 483 sockaddr_dl_init(struct sockaddr_dl *sdl, socklen_t socklen, uint16_t ifindex, 484 uint8_t type, const void *name, uint8_t namelen, const void *addr, 485 uint8_t addrlen) 486 { 487 socklen_t len; 488 489 sdl->sdl_family = AF_LINK; 490 sdl->sdl_slen = 0; 491 len = sockaddr_dl_measure(namelen, addrlen); 492 if (len > socklen) { 493 sdl->sdl_len = socklen; 494 #ifdef DIAGNOSTIC 495 printf("%s: too long: %u > %u\n", __func__, (u_int)len, 496 (u_int)socklen); 497 #endif 498 return NULL; 499 } 500 sdl->sdl_len = len; 501 sdl->sdl_index = ifindex; 502 sdl->sdl_type = type; 503 memset(&sdl->sdl_data[0], 0, namelen + addrlen); 504 if (name != NULL) { 505 memcpy(&sdl->sdl_data[0], name, namelen); 506 sdl->sdl_nlen = namelen; 507 } else 508 sdl->sdl_nlen = 0; 509 if (addr != NULL) { 510 memcpy(&sdl->sdl_data[sdl->sdl_nlen], addr, addrlen); 511 sdl->sdl_alen = addrlen; 512 } else 513 sdl->sdl_alen = 0; 514 return sdl; 515 } 516 517 static int 518 sockaddr_dl_cmp(const struct sockaddr *sa1, const struct sockaddr *sa2) 519 { 520 int rc; 521 const uint_fast8_t indexofs = offsetof(struct sockaddr_dl, sdl_index); 522 const uint_fast8_t nlenofs = offsetof(struct sockaddr_dl, sdl_nlen); 523 uint_fast8_t dataofs = offsetof(struct sockaddr_dl, sdl_data[0]); 524 const struct sockaddr_dl *sdl1, *sdl2; 525 526 sdl1 = satocsdl(sa1); 527 sdl2 = satocsdl(sa2); 528 529 rc = submemcmp(sdl1, sdl2, sdl1->sdl_len, sdl2->sdl_len, 530 indexofs, nlenofs); 531 532 if (rc != 0) 533 return rc; 534 535 rc = submemcmp(sdl1, sdl2, sdl1->sdl_len, sdl2->sdl_len, 536 dataofs, dataofs + MIN(sdl1->sdl_nlen, sdl2->sdl_nlen)); 537 538 if (rc != 0) 539 return rc; 540 541 if (sdl1->sdl_nlen != sdl2->sdl_nlen) 542 return sdl1->sdl_nlen - sdl2->sdl_nlen; 543 544 dataofs += sdl1->sdl_nlen; 545 546 rc = submemcmp(sdl1, sdl2, sdl1->sdl_len, sdl2->sdl_len, 547 dataofs, dataofs + MIN(sdl1->sdl_alen, sdl2->sdl_alen)); 548 549 if (rc != 0) 550 return rc; 551 552 if (sdl1->sdl_alen != sdl2->sdl_alen) 553 return sdl1->sdl_alen - sdl2->sdl_alen; 554 555 dataofs += sdl1->sdl_alen; 556 557 rc = submemcmp(sdl1, sdl2, sdl1->sdl_len, sdl2->sdl_len, 558 dataofs, dataofs + MIN(sdl1->sdl_slen, sdl2->sdl_slen)); 559 560 if (sdl1->sdl_slen != sdl2->sdl_slen) 561 return sdl1->sdl_slen - sdl2->sdl_slen; 562 563 return sdl1->sdl_len - sdl2->sdl_len; 564 } 565 566 struct sockaddr_dl * 567 sockaddr_dl_setaddr(struct sockaddr_dl *sdl, socklen_t socklen, 568 const void *addr, uint8_t addrlen) 569 { 570 socklen_t len; 571 572 len = sockaddr_dl_measure(sdl->sdl_nlen, addrlen); 573 if (len > socklen) { 574 #ifdef DIAGNOSTIC 575 printf("%s: too long: %u > %u\n", __func__, (u_int)len, 576 (u_int)socklen); 577 #endif 578 return NULL; 579 } 580 memcpy(&sdl->sdl_data[sdl->sdl_nlen], addr, addrlen); 581 sdl->sdl_alen = addrlen; 582 sdl->sdl_len = len; 583 return sdl; 584 } 585
Indexes created Sat Sep 20 22:09:52 GMT 2025