1 /* $NetBSD: if_arcsubr.c,v 1.86 2024/07/05 04:31:53 rin Exp $ */ 2 3 /* 4 * Copyright (c) 1994, 1995 Ignatios Souvatzis 5 * Copyright (c) 1982, 1989, 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 * 32 * from: NetBSD: if_ethersubr.c,v 1.9 1994/06/29 06:36:11 cgd Exp 33 * @(#)if_ethersubr.c 8.1 (Berkeley) 6/10/93 34 * 35 */ 36 37 #include <sys/cdefs.h> 38 __KERNEL_RCSID(0, "$NetBSD: if_arcsubr.c,v 1.86 2024/07/05 04:31:53 rin Exp $"); 39 40 #ifdef _KERNEL_OPT 41 #include "opt_inet.h" 42 #endif 43 44 #include <sys/param.h> 45 #include <sys/systm.h> 46 #include <sys/kernel.h> 47 #include <sys/malloc.h> 48 #include <sys/mbuf.h> 49 #include <sys/ioctl.h> 50 #include <sys/errno.h> 51 #include <sys/syslog.h> 52 53 #include <sys/cpu.h> 54 55 #include <net/if.h> 56 #include <net/route.h> 57 #include <net/if_dl.h> 58 #include <net/if_types.h> 59 #include <net/if_arc.h> 60 #include <net/if_arp.h> 61 #include <net/if_ether.h> 62 63 #include <net/bpf.h> 64 65 #ifdef INET 66 #include <netinet/in.h> 67 #include <netinet/in_var.h> 68 #include <netinet/if_inarp.h> 69 #endif 70 71 #ifdef INET6 72 #ifndef INET 73 #include <netinet/in.h> 74 #endif 75 #include <netinet6/in6_var.h> 76 #include <netinet6/nd6.h> 77 #endif 78 79 #define ARCNET_ALLOW_BROKEN_ARP 80 81 #ifndef ARC_IPMTU 82 #define ARC_IPMTU 1500 83 #endif 84 85 static struct mbuf *arc_defrag(struct ifnet *, struct mbuf *); 86 87 /* 88 * RC1201 requires us to have this configurable. We have it only per 89 * machine at the moment... there is no generic "set mtu" ioctl, AFAICS. 90 * Anyway, it is possible to binpatch this or set it per kernel config 91 * option. 92 */ 93 #if ARC_IPMTU > 60480 94 ERROR: The arc_ipmtu is ARC_IPMTU, but must not exceed 60480. 95 #endif 96 int arc_ipmtu = ARC_IPMTU; 97 uint8_t arcbroadcastaddr = 0; 98 99 #define senderr(e) { error = (e); goto bad;} 100 101 static int arc_output(struct ifnet *, struct mbuf *, 102 const struct sockaddr *, const struct rtentry *); 103 static void arc_input(struct ifnet *, struct mbuf *); 104 105 /* 106 * ARCnet output routine. 107 * Encapsulate a packet of type family for the local net. 108 * Assumes that ifp is actually pointer to arccom structure. 109 */ 110 static int 111 arc_output(struct ifnet *ifp, struct mbuf *m0, const struct sockaddr *dst, 112 const struct rtentry *rt) 113 { 114 struct mbuf *m, *m1, *mcopy; 115 struct arccom *ac; 116 const struct arc_header *cah; 117 struct arc_header *ah; 118 struct arphdr *arph; 119 int error, newencoding; 120 uint8_t atype, adst, myself; 121 int tfrags, sflag, fsflag, rsflag; 122 123 if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) != (IFF_UP|IFF_RUNNING)) 124 return (ENETDOWN); /* m, m1 aren't initialized yet */ 125 126 error = newencoding = 0; 127 ac = (struct arccom *)ifp; 128 m = m0; 129 mcopy = m1 = NULL; 130 131 myself = *CLLADDR(ifp->if_sadl); 132 133 /* 134 * if the queueing discipline needs packet classification, 135 * do it before prepending link headers. 136 */ 137 IFQ_CLASSIFY(&ifp->if_snd, m, dst->sa_family); 138 139 switch (dst->sa_family) { 140 #ifdef INET 141 case AF_INET: 142 143 /* 144 * For now, use the simple IP addr -> ARCnet addr mapping 145 */ 146 if (m->m_flags & (M_BCAST|M_MCAST)) 147 adst = arcbroadcastaddr; /* ARCnet broadcast address */ 148 else if (ifp->if_flags & IFF_NOARP) 149 adst = ntohl(satocsin(dst)->sin_addr.s_addr) & 0xFF; 150 else if ((error = arpresolve(ifp, rt, m, dst, &adst, 151 sizeof(adst))) != 0) 152 return error == EWOULDBLOCK ? 0 : error; 153 154 /* If broadcasting on a simplex interface, loopback a copy */ 155 if ((m->m_flags & (M_BCAST|M_MCAST)) && 156 (ifp->if_flags & IFF_SIMPLEX)) 157 mcopy = m_copypacket(m, M_DONTWAIT); 158 if (ifp->if_flags & IFF_LINK0) { 159 atype = ARCTYPE_IP; 160 newencoding = 1; 161 } else { 162 atype = ARCTYPE_IP_OLD; 163 newencoding = 0; 164 } 165 break; 166 167 case AF_ARP: 168 arph = mtod(m, struct arphdr *); 169 if (m->m_flags & M_BCAST) 170 adst = arcbroadcastaddr; 171 else { 172 uint8_t *tha = ar_tha(arph); 173 if (tha == NULL) { 174 m_freem(m); 175 return 0; 176 } 177 adst = *tha; 178 } 179 180 arph->ar_hrd = htons(ARPHRD_ARCNET); 181 182 switch (ntohs(arph->ar_op)) { 183 case ARPOP_REVREQUEST: 184 case ARPOP_REVREPLY: 185 if (!(ifp->if_flags & IFF_LINK0)) { 186 printf("%s: can't handle af%d\n", 187 ifp->if_xname, dst->sa_family); 188 senderr(EAFNOSUPPORT); 189 } 190 191 atype = htons(ARCTYPE_REVARP); 192 newencoding = 1; 193 break; 194 195 case ARPOP_REQUEST: 196 case ARPOP_REPLY: 197 default: 198 if (ifp->if_flags & IFF_LINK0) { 199 atype = htons(ARCTYPE_ARP); 200 newencoding = 1; 201 } else { 202 atype = htons(ARCTYPE_ARP_OLD); 203 newencoding = 0; 204 } 205 } 206 #ifdef ARCNET_ALLOW_BROKEN_ARP 207 /* 208 * XXX It's not clear per RFC826 if this is needed, but 209 * "assigned numbers" say this is wrong. 210 * However, e.g., AmiTCP 3.0Beta used it... we make this 211 * switchable for emergency cases. Not perfect, but... 212 */ 213 if (ifp->if_flags & IFF_LINK2) 214 arph->ar_pro = atype - 1; 215 #endif 216 break; 217 #endif 218 #ifdef INET6 219 case AF_INET6: 220 if (m->m_flags & M_MCAST) { 221 adst = 0; 222 } else { 223 error = nd6_resolve(ifp, rt, m, dst, &adst, 224 sizeof(adst)); 225 if (error != 0) 226 return error == EWOULDBLOCK ? 0 : error; 227 } 228 atype = htons(ARCTYPE_INET6); 229 newencoding = 1; 230 break; 231 #endif 232 233 case AF_UNSPEC: 234 cah = (const struct arc_header *)dst->sa_data; 235 adst = cah->arc_dhost; 236 atype = cah->arc_type; 237 break; 238 239 default: 240 printf("%s: can't handle af%d\n", ifp->if_xname, 241 dst->sa_family); 242 senderr(EAFNOSUPPORT); 243 } 244 245 if (mcopy) 246 (void) looutput(ifp, mcopy, dst, rt); 247 248 /* 249 * Add local net header. If no space in first mbuf, 250 * allocate another. 251 * 252 * For ARCnet, this is just symbolic. The header changes 253 * form and position on its way into the hardware and out of 254 * the wire. At this point, it contains source, destination and 255 * packet type. 256 */ 257 if (newencoding) { 258 ++ac->ac_seqid; /* make the seqid unique */ 259 260 tfrags = (m->m_pkthdr.len + 503) / 504; 261 fsflag = 2 * tfrags - 3; 262 sflag = 0; 263 rsflag = fsflag; 264 265 while (sflag < fsflag) { 266 /* we CAN'T have short packets here */ 267 m1 = m_split(m, 504, M_DONTWAIT); 268 if (m1 == 0) 269 senderr(ENOBUFS); 270 271 M_PREPEND(m, ARC_HDRNEWLEN, M_DONTWAIT); 272 if (m == 0) 273 senderr(ENOBUFS); 274 ah = mtod(m, struct arc_header *); 275 ah->arc_type = atype; 276 ah->arc_dhost = adst; 277 ah->arc_shost = myself; 278 ah->arc_flag = rsflag; 279 ah->arc_seqid = ac->ac_seqid; 280 281 if ((error = ifq_enqueue(ifp, m)) != 0) 282 return (error); 283 284 m = m1; 285 sflag += 2; 286 rsflag = sflag; 287 } 288 m1 = NULL; 289 290 291 /* here we can have small, especially forbidden packets */ 292 293 if ((m->m_pkthdr.len >= 294 ARC_MIN_FORBID_LEN - ARC_HDRNEWLEN + 2) && 295 (m->m_pkthdr.len <= 296 ARC_MAX_FORBID_LEN - ARC_HDRNEWLEN + 2)) { 297 298 M_PREPEND(m, ARC_HDRNEWLEN_EXC, M_DONTWAIT); 299 if (m == 0) 300 senderr(ENOBUFS); 301 ah = mtod(m, struct arc_header *); 302 ah->arc_flag = 0xFF; 303 ah->arc_seqid = 0xFFFF; 304 ah->arc_type2 = atype; 305 ah->arc_flag2 = sflag; 306 ah->arc_seqid2 = ac->ac_seqid; 307 } else { 308 M_PREPEND(m, ARC_HDRNEWLEN, M_DONTWAIT); 309 if (m == 0) 310 senderr(ENOBUFS); 311 ah = mtod(m, struct arc_header *); 312 ah->arc_flag = sflag; 313 ah->arc_seqid = ac->ac_seqid; 314 } 315 316 ah->arc_dhost = adst; 317 ah->arc_shost = myself; 318 ah->arc_type = atype; 319 } else { 320 M_PREPEND(m, ARC_HDRLEN, M_DONTWAIT); 321 if (m == 0) 322 senderr(ENOBUFS); 323 ah = mtod(m, struct arc_header *); 324 ah->arc_type = atype; 325 ah->arc_dhost = adst; 326 ah->arc_shost = myself; 327 } 328 329 return ifq_enqueue(ifp, m); 330 331 bad: 332 m_freem(m1); 333 m_freem(m); 334 return (error); 335 } 336 337 /* 338 * Defragmenter. Returns mbuf if last packet found, else 339 * NULL. frees imcoming mbuf as necessary. 340 */ 341 342 static struct mbuf * 343 arc_defrag(struct ifnet *ifp, struct mbuf *m) 344 { 345 struct arc_header *ah, *ah1; 346 struct arccom *ac; 347 struct ac_frag *af; 348 struct mbuf *m1; 349 const char *s; 350 int newflen; 351 u_char src, dst, typ; 352 353 ac = (struct arccom *)ifp; 354 355 if (m->m_len < ARC_HDRNEWLEN) { 356 m = m_pullup(m, ARC_HDRNEWLEN); 357 if (m == NULL) { 358 if_statinc(ifp, if_ierrors); 359 return NULL; 360 } 361 } 362 363 ah = mtod(m, struct arc_header *); 364 typ = ah->arc_type; 365 366 if (!arc_isphds(typ)) 367 return m; 368 369 src = ah->arc_shost; 370 dst = ah->arc_dhost; 371 372 if (ah->arc_flag == 0xff) { 373 m_adj(m, 4); 374 375 if (m->m_len < ARC_HDRNEWLEN) { 376 m = m_pullup(m, ARC_HDRNEWLEN); 377 if (m == NULL) { 378 if_statinc(ifp, if_ierrors); 379 return NULL; 380 } 381 } 382 383 ah = mtod(m, struct arc_header *); 384 } 385 386 af = &ac->ac_fragtab[src]; 387 m1 = af->af_packet; 388 s = "debug code error"; 389 390 if (ah->arc_flag & 1) { 391 /* 392 * first fragment. We always initialize, which is 393 * about the right thing to do, as we only want to 394 * accept one fragmented packet per src at a time. 395 */ 396 m_freem(m1); 397 398 af->af_packet = m; 399 m1 = m; 400 af->af_maxflag = ah->arc_flag; 401 af->af_lastseen = 0; 402 af->af_seqid = ah->arc_seqid; 403 404 return NULL; 405 /* notreached */ 406 } else { 407 /* check for unfragmented packet */ 408 if (ah->arc_flag == 0) 409 return m; 410 411 /* do we have a first packet from that src? */ 412 if (m1 == NULL) { 413 s = "no first frag"; 414 goto outofseq; 415 } 416 417 ah1 = mtod(m1, struct arc_header *); 418 419 if (ah->arc_seqid != ah1->arc_seqid) { 420 s = "seqid differs"; 421 goto outofseq; 422 } 423 424 if (typ != ah1->arc_type) { 425 s = "type differs"; 426 goto outofseq; 427 } 428 429 if (dst != ah1->arc_dhost) { 430 s = "dest host differs"; 431 goto outofseq; 432 } 433 434 /* typ, seqid and dst are ok here. */ 435 436 if (ah->arc_flag == af->af_lastseen) { 437 m_freem(m); 438 return NULL; 439 } 440 441 if (ah->arc_flag == af->af_lastseen + 2) { 442 /* ok, this is next fragment */ 443 af->af_lastseen = ah->arc_flag; 444 m_adj(m, ARC_HDRNEWLEN); 445 446 /* 447 * m_cat might free the first mbuf (with pkthdr) 448 * in 2nd chain; therefore: 449 */ 450 451 newflen = m->m_pkthdr.len; 452 453 m_cat(m1, m); 454 455 m1->m_pkthdr.len += newflen; 456 457 /* is it the last one? */ 458 if (af->af_lastseen > af->af_maxflag) { 459 af->af_packet = NULL; 460 return (m1); 461 } else 462 return NULL; 463 } 464 s = "other reason"; 465 /* if all else fails, it is out of sequence, too */ 466 } 467 outofseq: 468 if (m1) { 469 m_freem(m1); 470 af->af_packet = NULL; 471 } 472 473 m_freem(m); 474 475 log(LOG_INFO,"%s: got out of seq. packet: %s\n", 476 ifp->if_xname, s); 477 478 return NULL; 479 } 480 481 /* 482 * return 1 if Packet Header Definition Standard, else 0. 483 * For now: old IP, old ARP aren't obviously. Lacking correct information, 484 * we guess that besides new IP and new ARP also IPX and APPLETALK are PHDS. 485 * (Apple and Novell corporations were involved, among others, in PHDS work). 486 * Easiest is to assume that everybody else uses that, too. 487 */ 488 int 489 arc_isphds(uint8_t type) 490 { 491 return (type != ARCTYPE_IP_OLD && 492 type != ARCTYPE_ARP_OLD && 493 type != ARCTYPE_DIAGNOSE); 494 } 495 496 /* 497 * Process a received Arcnet packet; 498 * the packet is in the mbuf chain m with 499 * the ARCnet header. 500 */ 501 static void 502 arc_input(struct ifnet *ifp, struct mbuf *m) 503 { 504 pktqueue_t *pktq = NULL; 505 struct arc_header *ah; 506 uint8_t atype; 507 508 if ((ifp->if_flags & IFF_UP) == 0) { 509 m_freem(m); 510 return; 511 } 512 513 /* possibly defragment: */ 514 m = arc_defrag(ifp, m); 515 if (m == NULL) 516 return; 517 518 ah = mtod(m, struct arc_header *); 519 520 if_statadd(ifp, if_ibytes, m->m_pkthdr.len); 521 522 if (arcbroadcastaddr == ah->arc_dhost) { 523 m->m_flags |= M_BCAST|M_MCAST; 524 if_statinc(ifp, if_imcasts); 525 } 526 527 atype = ah->arc_type; 528 switch (atype) { 529 #ifdef INET 530 case ARCTYPE_IP: 531 m_adj(m, ARC_HDRNEWLEN); 532 pktq = ip_pktq; 533 break; 534 535 case ARCTYPE_IP_OLD: 536 m_adj(m, ARC_HDRLEN); 537 pktq = ip_pktq; 538 break; 539 540 case ARCTYPE_ARP: 541 m_adj(m, ARC_HDRNEWLEN); 542 pktq = arp_pktq; 543 #ifdef ARCNET_ALLOW_BROKEN_ARP 544 mtod(m, struct arphdr *)->ar_pro = htons(ETHERTYPE_IP); 545 #endif 546 break; 547 548 case ARCTYPE_ARP_OLD: 549 m_adj(m, ARC_HDRLEN); 550 pktq = arp_pktq; 551 #ifdef ARCNET_ALLOW_BROKEN_ARP 552 mtod(m, struct arphdr *)->ar_pro = htons(ETHERTYPE_IP); 553 #endif 554 break; 555 #endif 556 #ifdef INET6 557 case ARCTYPE_INET6: 558 m_adj(m, ARC_HDRNEWLEN); 559 pktq = ip6_pktq; 560 break; 561 #endif 562 default: 563 m_freem(m); 564 return; 565 } 566 567 KASSERT(pktq != NULL); 568 if (__predict_false(!pktq_enqueue(pktq, m, 0))) { 569 m_freem(m); 570 } 571 } 572 573 /* 574 * Convert Arcnet address to printable (loggable) representation. 575 */ 576 char * 577 arc_sprintf(uint8_t *ap) 578 { 579 static char arcbuf[3]; 580 char *cp = arcbuf; 581 582 *cp++ = hexdigits[*ap >> 4]; 583 *cp++ = hexdigits[*ap++ & 0xf]; 584 *cp = 0; 585 return (arcbuf); 586 } 587 588 /* 589 * Perform common duties while attaching to interface list 590 */ 591 int 592 arc_ifattach(struct ifnet *ifp, uint8_t lla) 593 { 594 struct arccom *ac; 595 596 ifp->if_type = IFT_ARCNET; 597 ifp->if_addrlen = 1; 598 ifp->if_hdrlen = ARC_HDRLEN; 599 ifp->if_dlt = DLT_ARCNET; 600 if (ifp->if_flags & IFF_BROADCAST) 601 ifp->if_flags |= IFF_MULTICAST|IFF_ALLMULTI; 602 if (ifp->if_flags & IFF_LINK0 && arc_ipmtu > ARC_PHDS_MAXMTU) 603 log(LOG_ERR, 604 "%s: arc_ipmtu is %d, but must not exceed %d\n", 605 ifp->if_xname, arc_ipmtu, ARC_PHDS_MAXMTU); 606 607 ifp->if_output = arc_output; 608 ifp->_if_input = arc_input; 609 ac = (struct arccom *)ifp; 610 ac->ac_seqid = (time_second) & 0xFFFF; /* try to make seqid unique */ 611 if (lla == 0) { 612 /* XXX this message isn't entirely clear, to me -- cgd */ 613 log(LOG_ERR,"%s: link address 0 reserved for broadcasts. Please change it and ifconfig %s down up\n", 614 ifp->if_xname, ifp->if_xname); 615 } 616 if_attach(ifp); 617 618 if_set_sadl(ifp, &lla, sizeof(lla), true); 619 620 ifp->if_broadcastaddr = &arcbroadcastaddr; 621 622 bpf_attach(ifp, DLT_ARCNET, ARC_HDRLEN); 623 624 return 0; 625 } 626
Indexes created Sat Sep 20 22:09:52 GMT 2025