1 /* $NetBSD: if_arcsubr.c,v 1.76 2017/01/24 18:37:20 maxv 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 1.76 2017/01/24 18:37:20 maxv 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 (!nd6_storelladdr(ifp, rt, m, dst, &adst, sizeof(adst))) 222 return (0); /* it must be impossible, but... */ 223 atype = htons(ARCTYPE_INET6); 224 newencoding = 1; 225 break; 226 #endif 227 228 case AF_UNSPEC: 229 cah = (const struct arc_header *)dst->sa_data; 230 adst = cah->arc_dhost; 231 atype = cah->arc_type; 232 break; 233 234 default: 235 printf("%s: can't handle af%d\n", ifp->if_xname, 236 dst->sa_family); 237 senderr(EAFNOSUPPORT); 238 } 239 240 if (mcopy) 241 (void) looutput(ifp, mcopy, dst, rt); 242 243 /* 244 * Add local net header. If no space in first mbuf, 245 * allocate another. 246 * 247 * For ARCnet, this is just symbolic. The header changes 248 * form and position on its way into the hardware and out of 249 * the wire. At this point, it contains source, destination and 250 * packet type. 251 */ 252 if (newencoding) { 253 ++ac->ac_seqid; /* make the seqid unique */ 254 255 tfrags = (m->m_pkthdr.len + 503) / 504; 256 fsflag = 2 * tfrags - 3; 257 sflag = 0; 258 rsflag = fsflag; 259 260 while (sflag < fsflag) { 261 /* we CAN'T have short packets here */ 262 m1 = m_split(m, 504, M_DONTWAIT); 263 if (m1 == 0) 264 senderr(ENOBUFS); 265 266 M_PREPEND(m, ARC_HDRNEWLEN, M_DONTWAIT); 267 if (m == 0) 268 senderr(ENOBUFS); 269 ah = mtod(m, struct arc_header *); 270 ah->arc_type = atype; 271 ah->arc_dhost = adst; 272 ah->arc_shost = myself; 273 ah->arc_flag = rsflag; 274 ah->arc_seqid = ac->ac_seqid; 275 276 if ((error = ifq_enqueue(ifp, m)) != 0) 277 return (error); 278 279 m = m1; 280 sflag += 2; 281 rsflag = sflag; 282 } 283 m1 = NULL; 284 285 286 /* here we can have small, especially forbidden packets */ 287 288 if ((m->m_pkthdr.len >= 289 ARC_MIN_FORBID_LEN - ARC_HDRNEWLEN + 2) && 290 (m->m_pkthdr.len <= 291 ARC_MAX_FORBID_LEN - ARC_HDRNEWLEN + 2)) { 292 293 M_PREPEND(m, ARC_HDRNEWLEN_EXC, M_DONTWAIT); 294 if (m == 0) 295 senderr(ENOBUFS); 296 ah = mtod(m, struct arc_header *); 297 ah->arc_flag = 0xFF; 298 ah->arc_seqid = 0xFFFF; 299 ah->arc_type2 = atype; 300 ah->arc_flag2 = sflag; 301 ah->arc_seqid2 = ac->ac_seqid; 302 } else { 303 M_PREPEND(m, ARC_HDRNEWLEN, M_DONTWAIT); 304 if (m == 0) 305 senderr(ENOBUFS); 306 ah = mtod(m, struct arc_header *); 307 ah->arc_flag = sflag; 308 ah->arc_seqid = ac->ac_seqid; 309 } 310 311 ah->arc_dhost = adst; 312 ah->arc_shost = myself; 313 ah->arc_type = atype; 314 } else { 315 M_PREPEND(m, ARC_HDRLEN, M_DONTWAIT); 316 if (m == 0) 317 senderr(ENOBUFS); 318 ah = mtod(m, struct arc_header *); 319 ah->arc_type = atype; 320 ah->arc_dhost = adst; 321 ah->arc_shost = myself; 322 } 323 324 return ifq_enqueue(ifp, m); 325 326 bad: 327 if (m1) 328 m_freem(m1); 329 if (m) 330 m_freem(m); 331 return (error); 332 } 333 334 /* 335 * Defragmenter. Returns mbuf if last packet found, else 336 * NULL. frees imcoming mbuf as necessary. 337 */ 338 339 static struct mbuf * 340 arc_defrag(struct ifnet *ifp, struct mbuf *m) 341 { 342 struct arc_header *ah, *ah1; 343 struct arccom *ac; 344 struct ac_frag *af; 345 struct mbuf *m1; 346 const char *s; 347 int newflen; 348 u_char src, dst, typ; 349 350 ac = (struct arccom *)ifp; 351 352 if (m->m_len < ARC_HDRNEWLEN) { 353 m = m_pullup(m, ARC_HDRNEWLEN); 354 if (m == NULL) { 355 ++ifp->if_ierrors; 356 return NULL; 357 } 358 } 359 360 ah = mtod(m, struct arc_header *); 361 typ = ah->arc_type; 362 363 if (!arc_isphds(typ)) 364 return m; 365 366 src = ah->arc_shost; 367 dst = ah->arc_dhost; 368 369 if (ah->arc_flag == 0xff) { 370 m_adj(m, 4); 371 372 if (m->m_len < ARC_HDRNEWLEN) { 373 m = m_pullup(m, ARC_HDRNEWLEN); 374 if (m == NULL) { 375 ++ifp->if_ierrors; 376 return NULL; 377 } 378 } 379 380 ah = mtod(m, struct arc_header *); 381 } 382 383 af = &ac->ac_fragtab[src]; 384 m1 = af->af_packet; 385 s = "debug code error"; 386 387 if (ah->arc_flag & 1) { 388 /* 389 * first fragment. We always initialize, which is 390 * about the right thing to do, as we only want to 391 * accept one fragmented packet per src at a time. 392 */ 393 if (m1 != NULL) 394 m_freem(m1); 395 396 af->af_packet = m; 397 m1 = m; 398 af->af_maxflag = ah->arc_flag; 399 af->af_lastseen = 0; 400 af->af_seqid = ah->arc_seqid; 401 402 return NULL; 403 /* notreached */ 404 } else { 405 /* check for unfragmented packet */ 406 if (ah->arc_flag == 0) 407 return m; 408 409 /* do we have a first packet from that src? */ 410 if (m1 == NULL) { 411 s = "no first frag"; 412 goto outofseq; 413 } 414 415 ah1 = mtod(m1, struct arc_header *); 416 417 if (ah->arc_seqid != ah1->arc_seqid) { 418 s = "seqid differs"; 419 goto outofseq; 420 } 421 422 if (typ != ah1->arc_type) { 423 s = "type differs"; 424 goto outofseq; 425 } 426 427 if (dst != ah1->arc_dhost) { 428 s = "dest host differs"; 429 goto outofseq; 430 } 431 432 /* typ, seqid and dst are ok here. */ 433 434 if (ah->arc_flag == af->af_lastseen) { 435 m_freem(m); 436 return NULL; 437 } 438 439 if (ah->arc_flag == af->af_lastseen + 2) { 440 /* ok, this is next fragment */ 441 af->af_lastseen = ah->arc_flag; 442 m_adj(m, ARC_HDRNEWLEN); 443 444 /* 445 * m_cat might free the first mbuf (with pkthdr) 446 * in 2nd chain; therefore: 447 */ 448 449 newflen = m->m_pkthdr.len; 450 451 m_cat(m1, m); 452 453 m1->m_pkthdr.len += newflen; 454 455 /* is it the last one? */ 456 if (af->af_lastseen > af->af_maxflag) { 457 af->af_packet = NULL; 458 return (m1); 459 } else 460 return NULL; 461 } 462 s = "other reason"; 463 /* if all else fails, it is out of sequence, too */ 464 } 465 outofseq: 466 if (m1) { 467 m_freem(m1); 468 af->af_packet = NULL; 469 } 470 471 if (m) 472 m_freem(m); 473 474 log(LOG_INFO,"%s: got out of seq. packet: %s\n", 475 ifp->if_xname, s); 476 477 return NULL; 478 } 479 480 /* 481 * return 1 if Packet Header Definition Standard, else 0. 482 * For now: old IP, old ARP aren't obviously. Lacking correct information, 483 * we guess that besides new IP and new ARP also IPX and APPLETALK are PHDS. 484 * (Apple and Novell corporations were involved, among others, in PHDS work). 485 * Easiest is to assume that everybody else uses that, too. 486 */ 487 int 488 arc_isphds(uint8_t type) 489 { 490 return (type != ARCTYPE_IP_OLD && 491 type != ARCTYPE_ARP_OLD && 492 type != ARCTYPE_DIAGNOSE); 493 } 494 495 /* 496 * Process a received Arcnet packet; 497 * the packet is in the mbuf chain m with 498 * the ARCnet header. 499 */ 500 static void 501 arc_input(struct ifnet *ifp, struct mbuf *m) 502 { 503 pktqueue_t *pktq = NULL; 504 struct arc_header *ah; 505 struct ifqueue *inq; 506 uint8_t atype; 507 int isr = 0; 508 509 if ((ifp->if_flags & IFF_UP) == 0) { 510 m_freem(m); 511 return; 512 } 513 514 /* possibly defragment: */ 515 m = arc_defrag(ifp, m); 516 if (m == NULL) 517 return; 518 519 ah = mtod(m, struct arc_header *); 520 521 ifp->if_ibytes += m->m_pkthdr.len; 522 523 if (arcbroadcastaddr == ah->arc_dhost) { 524 m->m_flags |= M_BCAST|M_MCAST; 525 ifp->if_imcasts++; 526 } 527 528 atype = ah->arc_type; 529 switch (atype) { 530 #ifdef INET 531 case ARCTYPE_IP: 532 m_adj(m, ARC_HDRNEWLEN); 533 pktq = ip_pktq; 534 break; 535 536 case ARCTYPE_IP_OLD: 537 m_adj(m, ARC_HDRLEN); 538 pktq = ip_pktq; 539 break; 540 541 case ARCTYPE_ARP: 542 m_adj(m, ARC_HDRNEWLEN); 543 isr = NETISR_ARP; 544 inq = &arpintrq; 545 #ifdef ARCNET_ALLOW_BROKEN_ARP 546 mtod(m, struct arphdr *)->ar_pro = htons(ETHERTYPE_IP); 547 #endif 548 break; 549 550 case ARCTYPE_ARP_OLD: 551 m_adj(m, ARC_HDRLEN); 552 isr = NETISR_ARP; 553 inq = &arpintrq; 554 #ifdef ARCNET_ALLOW_BROKEN_ARP 555 mtod(m, struct arphdr *)->ar_pro = htons(ETHERTYPE_IP); 556 #endif 557 break; 558 #endif 559 #ifdef INET6 560 case ARCTYPE_INET6: 561 m_adj(m, ARC_HDRNEWLEN); 562 pktq = ip6_pktq; 563 break; 564 #endif 565 default: 566 m_freem(m); 567 return; 568 } 569 570 if (__predict_true(pktq)) { 571 if (__predict_false(!pktq_enqueue(pktq, m, 0))) { 572 m_freem(m); 573 } 574 return; 575 } 576 577 IFQ_LOCK(inq); 578 if (IF_QFULL(inq)) { 579 IF_DROP(inq); 580 IFQ_UNLOCK(inq); 581 m_freem(m); 582 } else { 583 IF_ENQUEUE(inq, m); 584 IFQ_UNLOCK(inq); 585 schednetisr(isr); 586 } 587 } 588 589 /* 590 * Convert Arcnet address to printable (loggable) representation. 591 */ 592 char * 593 arc_sprintf(uint8_t *ap) 594 { 595 static char arcbuf[3]; 596 char *cp = arcbuf; 597 598 *cp++ = hexdigits[*ap >> 4]; 599 *cp++ = hexdigits[*ap++ & 0xf]; 600 *cp = 0; 601 return (arcbuf); 602 } 603 604 /* 605 * Perform common duties while attaching to interface list 606 */ 607 void 608 arc_ifattach(struct ifnet *ifp, uint8_t lla) 609 { 610 struct arccom *ac; 611 612 ifp->if_type = IFT_ARCNET; 613 ifp->if_addrlen = 1; 614 ifp->if_hdrlen = ARC_HDRLEN; 615 ifp->if_dlt = DLT_ARCNET; 616 if (ifp->if_flags & IFF_BROADCAST) 617 ifp->if_flags |= IFF_MULTICAST|IFF_ALLMULTI; 618 if (ifp->if_flags & IFF_LINK0 && arc_ipmtu > ARC_PHDS_MAXMTU) 619 log(LOG_ERR, 620 "%s: arc_ipmtu is %d, but must not exceed %d\n", 621 ifp->if_xname, arc_ipmtu, ARC_PHDS_MAXMTU); 622 623 ifp->if_output = arc_output; 624 ifp->_if_input = arc_input; 625 ac = (struct arccom *)ifp; 626 ac->ac_seqid = (time_second) & 0xFFFF; /* try to make seqid unique */ 627 if (lla == 0) { 628 /* XXX this message isn't entirely clear, to me -- cgd */ 629 log(LOG_ERR,"%s: link address 0 reserved for broadcasts. Please change it and ifconfig %s down up\n", 630 ifp->if_xname, ifp->if_xname); 631 } 632 if_attach(ifp); 633 if_set_sadl(ifp, &lla, sizeof(lla), true); 634 635 ifp->if_broadcastaddr = &arcbroadcastaddr; 636 637 bpf_attach(ifp, DLT_ARCNET, ARC_HDRLEN); 638 } 639