1 /* $NetBSD: if_arcsubr.c,v 1.77 2017/02/14 03:05:06 ozaki-r 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 1.77 2017/02/14 03:05:06 ozaki-r 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/netisr.h> 57 #include <net/route.h> 58 #include <net/if_dl.h> 59 #include <net/if_types.h> 60 #include <net/if_arc.h> 61 #include <net/if_arp.h> 62 #include <net/if_ether.h> 63 64 #include <net/bpf.h> 65 66 #ifdef INET 67 #include <netinet/in.h> 68 #include <netinet/in_var.h> 69 #include <netinet/if_inarp.h> 70 #endif 71 72 #ifdef INET6 73 #ifndef INET 74 #include <netinet/in.h> 75 #endif 76 #include <netinet6/in6_var.h> 77 #include <netinet6/nd6.h> 78 #endif 79 80 #define ARCNET_ALLOW_BROKEN_ARP 81 82 #ifndef ARC_IPMTU 83 #define ARC_IPMTU 1500 84 #endif 85 86 static struct mbuf *arc_defrag(struct ifnet *, struct mbuf *); 87 88 /* 89 * RC1201 requires us to have this configurable. We have it only per 90 * machine at the moment... there is no generic "set mtu" ioctl, AFAICS. 91 * Anyway, it is possible to binpatch this or set it per kernel config 92 * option. 93 */ 94 #if ARC_IPMTU > 60480 95 ERROR: The arc_ipmtu is ARC_IPMTU, but must not exceed 60480. 96 #endif 97 int arc_ipmtu = ARC_IPMTU; 98 uint8_t arcbroadcastaddr = 0; 99 100 #define senderr(e) { error = (e); goto bad;} 101 102 static int arc_output(struct ifnet *, struct mbuf *, 103 const struct sockaddr *, const struct rtentry *); 104 static void arc_input(struct ifnet *, struct mbuf *); 105 106 /* 107 * ARCnet output routine. 108 * Encapsulate a packet of type family for the local net. 109 * Assumes that ifp is actually pointer to arccom structure. 110 */ 111 static int 112 arc_output(struct ifnet *ifp, struct mbuf *m0, const struct sockaddr *dst, 113 const struct rtentry *rt) 114 { 115 struct mbuf *m, *m1, *mcopy; 116 struct arccom *ac; 117 const struct arc_header *cah; 118 struct arc_header *ah; 119 struct arphdr *arph; 120 int error, newencoding; 121 uint8_t atype, adst, myself; 122 int tfrags, sflag, fsflag, rsflag; 123 124 if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) != (IFF_UP|IFF_RUNNING)) 125 return (ENETDOWN); /* m, m1 aren't initialized yet */ 126 127 error = newencoding = 0; 128 ac = (struct arccom *)ifp; 129 m = m0; 130 mcopy = m1 = NULL; 131 132 myself = *CLLADDR(ifp->if_sadl); 133 134 /* 135 * if the queueing discipline needs packet classification, 136 * do it before prepending link headers. 137 */ 138 IFQ_CLASSIFY(&ifp->if_snd, m, dst->sa_family); 139 140 switch (dst->sa_family) { 141 #ifdef INET 142 case AF_INET: 143 144 /* 145 * For now, use the simple IP addr -> ARCnet addr mapping 146 */ 147 if (m->m_flags & (M_BCAST|M_MCAST)) 148 adst = arcbroadcastaddr; /* ARCnet broadcast address */ 149 else if (ifp->if_flags & IFF_NOARP) 150 adst = ntohl(satocsin(dst)->sin_addr.s_addr) & 0xFF; 151 else if ((error = arpresolve(ifp, rt, m, dst, &adst, 152 sizeof(adst))) != 0) 153 return error == EWOULDBLOCK ? 0 : error; 154 155 /* If broadcasting on a simplex interface, loopback a copy */ 156 if ((m->m_flags & (M_BCAST|M_MCAST)) && 157 (ifp->if_flags & IFF_SIMPLEX)) 158 mcopy = m_copy(m, 0, (int)M_COPYALL); 159 if (ifp->if_flags & IFF_LINK0) { 160 atype = ARCTYPE_IP; 161 newencoding = 1; 162 } else { 163 atype = ARCTYPE_IP_OLD; 164 newencoding = 0; 165 } 166 break; 167 168 case AF_ARP: 169 arph = mtod(m, struct arphdr *); 170 if (m->m_flags & M_BCAST) 171 adst = arcbroadcastaddr; 172 else { 173 uint8_t *tha = ar_tha(arph); 174 if (tha == NULL) { 175 m_freem(m); 176 return 0; 177 } 178 adst = *tha; 179 } 180 181 arph->ar_hrd = htons(ARPHRD_ARCNET); 182 183 switch (ntohs(arph->ar_op)) { 184 case ARPOP_REVREQUEST: 185 case ARPOP_REVREPLY: 186 if (!(ifp->if_flags & IFF_LINK0)) { 187 printf("%s: can't handle af%d\n", 188 ifp->if_xname, dst->sa_family); 189 senderr(EAFNOSUPPORT); 190 } 191 192 atype = htons(ARCTYPE_REVARP); 193 newencoding = 1; 194 break; 195 196 case ARPOP_REQUEST: 197 case ARPOP_REPLY: 198 default: 199 if (ifp->if_flags & IFF_LINK0) { 200 atype = htons(ARCTYPE_ARP); 201 newencoding = 1; 202 } else { 203 atype = htons(ARCTYPE_ARP_OLD); 204 newencoding = 0; 205 } 206 } 207 #ifdef ARCNET_ALLOW_BROKEN_ARP 208 /* 209 * XXX It's not clear per RFC826 if this is needed, but 210 * "assigned numbers" say this is wrong. 211 * However, e.g., AmiTCP 3.0Beta used it... we make this 212 * switchable for emergency cases. Not perfect, but... 213 */ 214 if (ifp->if_flags & IFF_LINK2) 215 arph->ar_pro = atype - 1; 216 #endif 217 break; 218 #endif 219 #ifdef INET6 220 case AF_INET6: 221 if (m->m_flags & M_MCAST) { 222 adst = 0; 223 } else { 224 error = nd6_resolve(ifp, rt, m, dst, &adst, 225 sizeof(adst)); 226 if (error != 0) 227 return error == EWOULDBLOCK ? 0 : error; 228 } 229 atype = htons(ARCTYPE_INET6); 230 newencoding = 1; 231 break; 232 #endif 233 234 case AF_UNSPEC: 235 cah = (const struct arc_header *)dst->sa_data; 236 adst = cah->arc_dhost; 237 atype = cah->arc_type; 238 break; 239 240 default: 241 printf("%s: can't handle af%d\n", ifp->if_xname, 242 dst->sa_family); 243 senderr(EAFNOSUPPORT); 244 } 245 246 if (mcopy) 247 (void) looutput(ifp, mcopy, dst, rt); 248 249 /* 250 * Add local net header. If no space in first mbuf, 251 * allocate another. 252 * 253 * For ARCnet, this is just symbolic. The header changes 254 * form and position on its way into the hardware and out of 255 * the wire. At this point, it contains source, destination and 256 * packet type. 257 */ 258 if (newencoding) { 259 ++ac->ac_seqid; /* make the seqid unique */ 260 261 tfrags = (m->m_pkthdr.len + 503) / 504; 262 fsflag = 2 * tfrags - 3; 263 sflag = 0; 264 rsflag = fsflag; 265 266 while (sflag < fsflag) { 267 /* we CAN'T have short packets here */ 268 m1 = m_split(m, 504, M_DONTWAIT); 269 if (m1 == 0) 270 senderr(ENOBUFS); 271 272 M_PREPEND(m, ARC_HDRNEWLEN, M_DONTWAIT); 273 if (m == 0) 274 senderr(ENOBUFS); 275 ah = mtod(m, struct arc_header *); 276 ah->arc_type = atype; 277 ah->arc_dhost = adst; 278 ah->arc_shost = myself; 279 ah->arc_flag = rsflag; 280 ah->arc_seqid = ac->ac_seqid; 281 282 if ((error = ifq_enqueue(ifp, m)) != 0) 283 return (error); 284 285 m = m1; 286 sflag += 2; 287 rsflag = sflag; 288 } 289 m1 = NULL; 290 291 292 /* here we can have small, especially forbidden packets */ 293 294 if ((m->m_pkthdr.len >= 295 ARC_MIN_FORBID_LEN - ARC_HDRNEWLEN + 2) && 296 (m->m_pkthdr.len <= 297 ARC_MAX_FORBID_LEN - ARC_HDRNEWLEN + 2)) { 298 299 M_PREPEND(m, ARC_HDRNEWLEN_EXC, M_DONTWAIT); 300 if (m == 0) 301 senderr(ENOBUFS); 302 ah = mtod(m, struct arc_header *); 303 ah->arc_flag = 0xFF; 304 ah->arc_seqid = 0xFFFF; 305 ah->arc_type2 = atype; 306 ah->arc_flag2 = sflag; 307 ah->arc_seqid2 = ac->ac_seqid; 308 } else { 309 M_PREPEND(m, ARC_HDRNEWLEN, M_DONTWAIT); 310 if (m == 0) 311 senderr(ENOBUFS); 312 ah = mtod(m, struct arc_header *); 313 ah->arc_flag = sflag; 314 ah->arc_seqid = ac->ac_seqid; 315 } 316 317 ah->arc_dhost = adst; 318 ah->arc_shost = myself; 319 ah->arc_type = atype; 320 } else { 321 M_PREPEND(m, ARC_HDRLEN, M_DONTWAIT); 322 if (m == 0) 323 senderr(ENOBUFS); 324 ah = mtod(m, struct arc_header *); 325 ah->arc_type = atype; 326 ah->arc_dhost = adst; 327 ah->arc_shost = myself; 328 } 329 330 return ifq_enqueue(ifp, m); 331 332 bad: 333 if (m1) 334 m_freem(m1); 335 if (m) 336 m_freem(m); 337 return (error); 338 } 339 340 /* 341 * Defragmenter. Returns mbuf if last packet found, else 342 * NULL. frees imcoming mbuf as necessary. 343 */ 344 345 static struct mbuf * 346 arc_defrag(struct ifnet *ifp, struct mbuf *m) 347 { 348 struct arc_header *ah, *ah1; 349 struct arccom *ac; 350 struct ac_frag *af; 351 struct mbuf *m1; 352 const char *s; 353 int newflen; 354 u_char src, dst, typ; 355 356 ac = (struct arccom *)ifp; 357 358 if (m->m_len < ARC_HDRNEWLEN) { 359 m = m_pullup(m, ARC_HDRNEWLEN); 360 if (m == NULL) { 361 ++ifp->if_ierrors; 362 return NULL; 363 } 364 } 365 366 ah = mtod(m, struct arc_header *); 367 typ = ah->arc_type; 368 369 if (!arc_isphds(typ)) 370 return m; 371 372 src = ah->arc_shost; 373 dst = ah->arc_dhost; 374 375 if (ah->arc_flag == 0xff) { 376 m_adj(m, 4); 377 378 if (m->m_len < ARC_HDRNEWLEN) { 379 m = m_pullup(m, ARC_HDRNEWLEN); 380 if (m == NULL) { 381 ++ifp->if_ierrors; 382 return NULL; 383 } 384 } 385 386 ah = mtod(m, struct arc_header *); 387 } 388 389 af = &ac->ac_fragtab[src]; 390 m1 = af->af_packet; 391 s = "debug code error"; 392 393 if (ah->arc_flag & 1) { 394 /* 395 * first fragment. We always initialize, which is 396 * about the right thing to do, as we only want to 397 * accept one fragmented packet per src at a time. 398 */ 399 if (m1 != NULL) 400 m_freem(m1); 401 402 af->af_packet = m; 403 m1 = m; 404 af->af_maxflag = ah->arc_flag; 405 af->af_lastseen = 0; 406 af->af_seqid = ah->arc_seqid; 407 408 return NULL; 409 /* notreached */ 410 } else { 411 /* check for unfragmented packet */ 412 if (ah->arc_flag == 0) 413 return m; 414 415 /* do we have a first packet from that src? */ 416 if (m1 == NULL) { 417 s = "no first frag"; 418 goto outofseq; 419 } 420 421 ah1 = mtod(m1, struct arc_header *); 422 423 if (ah->arc_seqid != ah1->arc_seqid) { 424 s = "seqid differs"; 425 goto outofseq; 426 } 427 428 if (typ != ah1->arc_type) { 429 s = "type differs"; 430 goto outofseq; 431 } 432 433 if (dst != ah1->arc_dhost) { 434 s = "dest host differs"; 435 goto outofseq; 436 } 437 438 /* typ, seqid and dst are ok here. */ 439 440 if (ah->arc_flag == af->af_lastseen) { 441 m_freem(m); 442 return NULL; 443 } 444 445 if (ah->arc_flag == af->af_lastseen + 2) { 446 /* ok, this is next fragment */ 447 af->af_lastseen = ah->arc_flag; 448 m_adj(m, ARC_HDRNEWLEN); 449 450 /* 451 * m_cat might free the first mbuf (with pkthdr) 452 * in 2nd chain; therefore: 453 */ 454 455 newflen = m->m_pkthdr.len; 456 457 m_cat(m1, m); 458 459 m1->m_pkthdr.len += newflen; 460 461 /* is it the last one? */ 462 if (af->af_lastseen > af->af_maxflag) { 463 af->af_packet = NULL; 464 return (m1); 465 } else 466 return NULL; 467 } 468 s = "other reason"; 469 /* if all else fails, it is out of sequence, too */ 470 } 471 outofseq: 472 if (m1) { 473 m_freem(m1); 474 af->af_packet = NULL; 475 } 476 477 if (m) 478 m_freem(m); 479 480 log(LOG_INFO,"%s: got out of seq. packet: %s\n", 481 ifp->if_xname, s); 482 483 return NULL; 484 } 485 486 /* 487 * return 1 if Packet Header Definition Standard, else 0. 488 * For now: old IP, old ARP aren't obviously. Lacking correct information, 489 * we guess that besides new IP and new ARP also IPX and APPLETALK are PHDS. 490 * (Apple and Novell corporations were involved, among others, in PHDS work). 491 * Easiest is to assume that everybody else uses that, too. 492 */ 493 int 494 arc_isphds(uint8_t type) 495 { 496 return (type != ARCTYPE_IP_OLD && 497 type != ARCTYPE_ARP_OLD && 498 type != ARCTYPE_DIAGNOSE); 499 } 500 501 /* 502 * Process a received Arcnet packet; 503 * the packet is in the mbuf chain m with 504 * the ARCnet header. 505 */ 506 static void 507 arc_input(struct ifnet *ifp, struct mbuf *m) 508 { 509 pktqueue_t *pktq = NULL; 510 struct arc_header *ah; 511 struct ifqueue *inq; 512 uint8_t atype; 513 int isr = 0; 514 515 if ((ifp->if_flags & IFF_UP) == 0) { 516 m_freem(m); 517 return; 518 } 519 520 /* possibly defragment: */ 521 m = arc_defrag(ifp, m); 522 if (m == NULL) 523 return; 524 525 ah = mtod(m, struct arc_header *); 526 527 ifp->if_ibytes += m->m_pkthdr.len; 528 529 if (arcbroadcastaddr == ah->arc_dhost) { 530 m->m_flags |= M_BCAST|M_MCAST; 531 ifp->if_imcasts++; 532 } 533 534 atype = ah->arc_type; 535 switch (atype) { 536 #ifdef INET 537 case ARCTYPE_IP: 538 m_adj(m, ARC_HDRNEWLEN); 539 pktq = ip_pktq; 540 break; 541 542 case ARCTYPE_IP_OLD: 543 m_adj(m, ARC_HDRLEN); 544 pktq = ip_pktq; 545 break; 546 547 case ARCTYPE_ARP: 548 m_adj(m, ARC_HDRNEWLEN); 549 isr = NETISR_ARP; 550 inq = &arpintrq; 551 #ifdef ARCNET_ALLOW_BROKEN_ARP 552 mtod(m, struct arphdr *)->ar_pro = htons(ETHERTYPE_IP); 553 #endif 554 break; 555 556 case ARCTYPE_ARP_OLD: 557 m_adj(m, ARC_HDRLEN); 558 isr = NETISR_ARP; 559 inq = &arpintrq; 560 #ifdef ARCNET_ALLOW_BROKEN_ARP 561 mtod(m, struct arphdr *)->ar_pro = htons(ETHERTYPE_IP); 562 #endif 563 break; 564 #endif 565 #ifdef INET6 566 case ARCTYPE_INET6: 567 m_adj(m, ARC_HDRNEWLEN); 568 pktq = ip6_pktq; 569 break; 570 #endif 571 default: 572 m_freem(m); 573 return; 574 } 575 576 if (__predict_true(pktq)) { 577 if (__predict_false(!pktq_enqueue(pktq, m, 0))) { 578 m_freem(m); 579 } 580 return; 581 } 582 583 IFQ_LOCK(inq); 584 if (IF_QFULL(inq)) { 585 IF_DROP(inq); 586 IFQ_UNLOCK(inq); 587 m_freem(m); 588 } else { 589 IF_ENQUEUE(inq, m); 590 IFQ_UNLOCK(inq); 591 schednetisr(isr); 592 } 593 } 594 595 /* 596 * Convert Arcnet address to printable (loggable) representation. 597 */ 598 char * 599 arc_sprintf(uint8_t *ap) 600 { 601 static char arcbuf[3]; 602 char *cp = arcbuf; 603 604 *cp++ = hexdigits[*ap >> 4]; 605 *cp++ = hexdigits[*ap++ & 0xf]; 606 *cp = 0; 607 return (arcbuf); 608 } 609 610 /* 611 * Perform common duties while attaching to interface list 612 */ 613 void 614 arc_ifattach(struct ifnet *ifp, uint8_t lla) 615 { 616 struct arccom *ac; 617 618 ifp->if_type = IFT_ARCNET; 619 ifp->if_addrlen = 1; 620 ifp->if_hdrlen = ARC_HDRLEN; 621 ifp->if_dlt = DLT_ARCNET; 622 if (ifp->if_flags & IFF_BROADCAST) 623 ifp->if_flags |= IFF_MULTICAST|IFF_ALLMULTI; 624 if (ifp->if_flags & IFF_LINK0 && arc_ipmtu > ARC_PHDS_MAXMTU) 625 log(LOG_ERR, 626 "%s: arc_ipmtu is %d, but must not exceed %d\n", 627 ifp->if_xname, arc_ipmtu, ARC_PHDS_MAXMTU); 628 629 ifp->if_output = arc_output; 630 ifp->_if_input = arc_input; 631 ac = (struct arccom *)ifp; 632 ac->ac_seqid = (time_second) & 0xFFFF; /* try to make seqid unique */ 633 if (lla == 0) { 634 /* XXX this message isn't entirely clear, to me -- cgd */ 635 log(LOG_ERR,"%s: link address 0 reserved for broadcasts. Please change it and ifconfig %s down up\n", 636 ifp->if_xname, ifp->if_xname); 637 } 638 if_attach(ifp); 639 if_set_sadl(ifp, &lla, sizeof(lla), true); 640 641 ifp->if_broadcastaddr = &arcbroadcastaddr; 642 643 bpf_attach(ifp, DLT_ARCNET, ARC_HDRLEN); 644 } 645