if_sl.c revision 1.111
1/* $NetBSD: if_sl.c,v 1.111 2008/04/24 11:38:37 ad Exp $ */ 2 3/* 4 * Copyright (c) 1987, 1989, 1992, 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 * @(#)if_sl.c 8.9 (Berkeley) 1/9/95 32 */ 33 34/* 35 * Serial Line interface 36 * 37 * Rick Adams 38 * Center for Seismic Studies 39 * 1300 N 17th Street, Suite 1450 40 * Arlington, Virginia 22209 41 * (703)276-7900 42 * rick@seismo.ARPA 43 * seismo!rick 44 * 45 * Pounded on heavily by Chris Torek (chris@mimsy.umd.edu, umcp-cs!chris). 46 * N.B.: this belongs in netinet, not net, the way it stands now. 47 * Should have a link-layer type designation, but wouldn't be 48 * backwards-compatible. 49 * 50 * Converted to 4.3BSD Beta by Chris Torek. 51 * Other changes made at Berkeley, based in part on code by Kirk Smith. 52 * W. Jolitz added slip abort. 53 * 54 * Hacked almost beyond recognition by Van Jacobson (van@helios.ee.lbl.gov). 55 * Added priority queuing for "interactive" traffic; hooks for TCP 56 * header compression; ICMP filtering (at 2400 baud, some cretin 57 * pinging you can use up all your bandwidth). Made low clist behavior 58 * more robust and slightly less likely to hang serial line. 59 * Sped up a bunch of things. 60 */ 61 62#include <sys/cdefs.h> 63__KERNEL_RCSID(0, "$NetBSD: if_sl.c,v 1.111 2008/04/24 11:38:37 ad Exp $"); 64 65#include "opt_inet.h" 66#include "bpfilter.h" 67 68#include <sys/param.h> 69#include <sys/proc.h> 70#include <sys/malloc.h> 71#include <sys/mbuf.h> 72#include <sys/buf.h> 73#include <sys/dkstat.h> 74#include <sys/socket.h> 75#include <sys/ioctl.h> 76#include <sys/file.h> 77#include <sys/conf.h> 78#include <sys/tty.h> 79#include <sys/kernel.h> 80#include <sys/socketvar.h> 81#if __NetBSD__ 82#include <sys/systm.h> 83#include <sys/kauth.h> 84#endif 85#include <sys/cpu.h> 86#include <sys/intr.h> 87 88#include <net/if.h> 89#include <net/if_types.h> 90#include <net/netisr.h> 91#include <net/route.h> 92 93#ifdef INET 94#include <netinet/in.h> 95#include <netinet/in_systm.h> 96#include <netinet/in_var.h> 97#include <netinet/ip.h> 98#endif 99 100#include <net/slcompress.h> 101#include <net/if_slvar.h> 102#include <net/slip.h> 103#include <net/ppp_defs.h> 104#include <net/if_ppp.h> 105 106#if NBPFILTER > 0 107#include <sys/time.h> 108#include <net/bpf.h> 109#endif 110 111/* 112 * SLMAX is a hard limit on input packet size. To simplify the code 113 * and improve performance, we require that packets fit in an mbuf 114 * cluster, and if we get a compressed packet, there's enough extra 115 * room to expand the header into a max length tcp/ip header (128 116 * bytes). So, SLMAX can be at most 117 * MCLBYTES - 128 118 * 119 * SLMTU is a hard limit on output packet size. To insure good 120 * interactive response, SLMTU wants to be the smallest size that 121 * amortizes the header cost. (Remember that even with 122 * type-of-service queuing, we have to wait for any in-progress 123 * packet to finish. I.e., we wait, on the average, 1/2 * mtu / 124 * cps, where cps is the line speed in characters per second. 125 * E.g., 533ms wait for a 1024 byte MTU on a 9600 baud line. The 126 * average compressed header size is 6-8 bytes so any MTU > 90 127 * bytes will give us 90% of the line bandwidth. A 100ms wait is 128 * tolerable (500ms is not), so want an MTU around 296. (Since TCP 129 * will send 256 byte segments (to allow for 40 byte headers), the 130 * typical packet size on the wire will be around 260 bytes). In 131 * 4.3tahoe+ systems, we can set an MTU in a route so we do that & 132 * leave the interface MTU relatively high (so we don't IP fragment 133 * when acting as a gateway to someone using a stupid MTU). 134 * 135 * Similar considerations apply to SLIP_HIWAT: It's the amount of 136 * data that will be queued 'downstream' of us (i.e., in clists 137 * waiting to be picked up by the tty output interrupt). If we 138 * queue a lot of data downstream, it's immune to our t.o.s. queuing. 139 * E.g., if SLIP_HIWAT is 1024, the interactive traffic in mixed 140 * telnet/ftp will see a 1 sec wait, independent of the mtu (the 141 * wait is dependent on the ftp window size but that's typically 142 * 1k - 4k). So, we want SLIP_HIWAT just big enough to amortize 143 * the cost (in idle time on the wire) of the tty driver running 144 * off the end of its clists & having to call back slstart for a 145 * new packet. For a tty interface with any buffering at all, this 146 * cost will be zero. Even with a totally brain dead interface (like 147 * the one on a typical workstation), the cost will be <= 1 character 148 * time. So, setting SLIP_HIWAT to ~100 guarantees that we'll lose 149 * at most 1% while maintaining good interactive response. 150 */ 151#define BUFOFFSET (128+sizeof(struct ifnet **)+SLIP_HDRLEN) 152#define SLMAX (MCLBYTES - BUFOFFSET) 153#define SLBUFSIZE (SLMAX + BUFOFFSET) 154#ifndef SLMTU 155#define SLMTU 296 156#endif 157#if (SLMTU < 3) 158#error SLMTU way too small. 159#endif 160#define SLIP_HIWAT roundup(50,CBSIZE) 161#ifndef __NetBSD__ /* XXX - cgd */ 162#define CLISTRESERVE 1024 /* Can't let clists get too low */ 163#endif /* !__NetBSD__ */ 164 165/* 166 * SLIP ABORT ESCAPE MECHANISM: 167 * (inspired by HAYES modem escape arrangement) 168 * 1sec escape 1sec escape 1sec escape { 1sec escape 1sec escape } 169 * within window time signals a "soft" exit from slip mode by remote end 170 * if the IFF_DEBUG flag is on. 171 */ 172#define ABT_ESC '\033' /* can't be t_intr - distant host must know it*/ 173#define ABT_IDLE 1 /* in seconds - idle before an escape */ 174#define ABT_COUNT 3 /* count of escapes for abort */ 175#define ABT_WINDOW (ABT_COUNT*2+2) /* in seconds - time to count */ 176 177static int sl_clone_create(struct if_clone *, int); 178static int sl_clone_destroy(struct ifnet *); 179 180static LIST_HEAD(, sl_softc) sl_softc_list; 181 182struct if_clone sl_cloner = 183 IF_CLONE_INITIALIZER("sl", sl_clone_create, sl_clone_destroy); 184 185#define FRAME_END 0xc0 /* Frame End */ 186#define FRAME_ESCAPE 0xdb /* Frame Esc */ 187#define TRANS_FRAME_END 0xdc /* transposed frame end */ 188#define TRANS_FRAME_ESCAPE 0xdd /* transposed frame esc */ 189 190static void slintr(void *); 191 192static int slinit(struct sl_softc *); 193static struct mbuf *sl_btom(struct sl_softc *, int); 194 195static int slclose(struct tty *, int); 196static int slinput(int, struct tty *); 197static int slioctl(struct ifnet *, u_long, void *); 198static int slopen(dev_t, struct tty *); 199static int sloutput(struct ifnet *, struct mbuf *, const struct sockaddr *, 200 struct rtentry *); 201static int slstart(struct tty *); 202static int sltioctl(struct tty *, u_long, void *, int, struct lwp *); 203 204static struct linesw slip_disc = { 205 .l_name = "slip", 206 .l_open = slopen, 207 .l_close = slclose, 208 .l_read = ttyerrio, 209 .l_write = ttyerrio, 210 .l_ioctl = sltioctl, 211 .l_rint = slinput, 212 .l_start = slstart, 213 .l_modem = nullmodem, 214 .l_poll = ttyerrpoll 215}; 216 217void slattach(void); 218 219void 220slattach(void) 221{ 222 223 if (ttyldisc_attach(&slip_disc) != 0) 224 panic("slattach"); 225 LIST_INIT(&sl_softc_list); 226 if_clone_attach(&sl_cloner); 227} 228 229static int 230sl_clone_create(struct if_clone *ifc, int unit) 231{ 232 struct sl_softc *sc; 233 234 MALLOC(sc, struct sl_softc *, sizeof(*sc), M_DEVBUF, M_WAIT|M_ZERO); 235 sc->sc_unit = unit; 236 (void)snprintf(sc->sc_if.if_xname, sizeof(sc->sc_if.if_xname), 237 "%s%d", ifc->ifc_name, unit); 238 sc->sc_if.if_softc = sc; 239 sc->sc_if.if_mtu = SLMTU; 240 sc->sc_if.if_flags = IFF_POINTOPOINT | SC_AUTOCOMP | IFF_MULTICAST; 241 sc->sc_if.if_type = IFT_SLIP; 242 sc->sc_if.if_ioctl = slioctl; 243 sc->sc_if.if_output = sloutput; 244 sc->sc_if.if_dlt = DLT_SLIP; 245 sc->sc_fastq.ifq_maxlen = 32; 246 IFQ_SET_READY(&sc->sc_if.if_snd); 247 if_attach(&sc->sc_if); 248 if_alloc_sadl(&sc->sc_if); 249#if NBPFILTER > 0 250 bpfattach(&sc->sc_if, DLT_SLIP, SLIP_HDRLEN); 251#endif 252 LIST_INSERT_HEAD(&sl_softc_list, sc, sc_iflist); 253 return 0; 254} 255 256static int 257sl_clone_destroy(struct ifnet *ifp) 258{ 259 struct sl_softc *sc = (struct sl_softc *)ifp->if_softc; 260 261 if (sc->sc_ttyp != NULL) 262 return EBUSY; /* Not removing it */ 263 264 LIST_REMOVE(sc, sc_iflist); 265 266#if NBPFILTER > 0 267 bpfdetach(ifp); 268#endif 269 if_detach(ifp); 270 271 FREE(sc, M_DEVBUF); 272 return 0; 273} 274 275static int 276slinit(struct sl_softc *sc) 277{ 278 279 if (sc->sc_mbuf == NULL) { 280 sc->sc_mbuf = m_gethdr(M_WAIT, MT_DATA); 281 m_clget(sc->sc_mbuf, M_WAIT); 282 } 283 sc->sc_ep = (u_char *)sc->sc_mbuf->m_ext.ext_buf + 284 sc->sc_mbuf->m_ext.ext_size; 285 sc->sc_mp = sc->sc_pktstart = (u_char *)sc->sc_mbuf->m_ext.ext_buf + 286 BUFOFFSET; 287 288#ifdef INET 289 sl_compress_init(&sc->sc_comp); 290#endif 291 292 return 1; 293} 294 295/* 296 * Line specific open routine. 297 * Attach the given tty to the first available sl unit. 298 */ 299/* ARGSUSED */ 300static int 301slopen(dev_t dev, struct tty *tp) 302{ 303 struct lwp *l = curlwp; /* XXX */ 304 struct sl_softc *sc; 305 int error; 306 307 if ((error = kauth_authorize_generic(l->l_cred, KAUTH_GENERIC_ISSUSER, 308 NULL)) != 0) 309 return error; 310 311 if (tp->t_linesw == &slip_disc) 312 return 0; 313 314 LIST_FOREACH(sc, &sl_softc_list, sc_iflist) 315 if (sc->sc_ttyp == NULL) { 316 sc->sc_si = softint_establish(SOFTINT_NET, 317 slintr, sc); 318 if (sc->sc_si == NULL) 319 return ENOMEM; 320 if (slinit(sc) == 0) { 321 softint_disestablish(sc->sc_si); 322 return ENOBUFS; 323 } 324 tp->t_sc = (void *)sc; 325 sc->sc_ttyp = tp; 326 sc->sc_if.if_baudrate = tp->t_ospeed; 327 mutex_spin_enter(&tty_lock); 328 tp->t_state |= TS_ISOPEN | TS_XCLUDE; 329 ttyflush(tp, FREAD | FWRITE); 330 /* 331 * make sure tty output queue is large enough 332 * to hold a full-sized packet (including frame 333 * end, and a possible extra frame end). full-sized 334 * packet occupies a max of 2*SLMAX bytes (because 335 * of possible escapes), and add two on for frame 336 * ends. 337 */ 338 if (tp->t_outq.c_cn < 2 * SLMAX + 2) { 339 sc->sc_oldbufsize = tp->t_outq.c_cn; 340 sc->sc_oldbufquot = tp->t_outq.c_cq != 0; 341 342 clfree(&tp->t_outq); 343 mutex_spin_exit(&tty_lock); 344 error = clalloc(&tp->t_outq, 2 * SLMAX + 2, 0); 345 if (error) { 346 softint_disestablish(sc->sc_si); 347 /* 348 * clalloc() might return -1 which 349 * is no good, so we need to return 350 * something else. 351 */ 352 return ENOMEM; /* XXX ?! */ 353 } 354 } else { 355 sc->sc_oldbufsize = sc->sc_oldbufquot = 0; 356 mutex_spin_exit(&tty_lock); 357 } 358 return 0; 359 } 360 return ENXIO; 361} 362 363/* 364 * Line specific close routine. 365 * Detach the tty from the sl unit. 366 */ 367static int 368slclose(struct tty *tp, int flag) 369{ 370 struct sl_softc *sc; 371 int s; 372 373 ttywflush(tp); 374 sc = tp->t_sc; 375 376 if (sc != NULL) { 377 softint_disestablish(sc->sc_si); 378 s = splnet(); 379 if_down(&sc->sc_if); 380 IF_PURGE(&sc->sc_fastq); 381 splx(s); 382 383 s = spltty(); 384 ttyldisc_release(tp->t_linesw); 385 tp->t_linesw = ttyldisc_default(); 386 tp->t_state = 0; 387 388 sc->sc_ttyp = NULL; 389 tp->t_sc = NULL; 390 391 m_freem(sc->sc_mbuf); 392 sc->sc_mbuf = NULL; 393 sc->sc_ep = sc->sc_mp = sc->sc_pktstart = NULL; 394 IF_PURGE(&sc->sc_inq); 395 396 /* 397 * If necessary, install a new outq buffer of the 398 * appropriate size. 399 */ 400 if (sc->sc_oldbufsize != 0) { 401 clfree(&tp->t_outq); 402 clalloc(&tp->t_outq, sc->sc_oldbufsize, 403 sc->sc_oldbufquot); 404 } 405 splx(s); 406 } 407 408 return 0; 409} 410 411/* 412 * Line specific (tty) ioctl routine. 413 * Provide a way to get the sl unit number. 414 */ 415/* ARGSUSED */ 416static int 417sltioctl(struct tty *tp, u_long cmd, void *data, int flag, 418 struct lwp *l) 419{ 420 struct sl_softc *sc = (struct sl_softc *)tp->t_sc; 421 422 switch (cmd) { 423 case SLIOCGUNIT: 424 *(int *)data = sc->sc_unit; /* XXX */ 425 break; 426 427 default: 428 return EPASSTHROUGH; 429 } 430 return 0; 431} 432 433/* 434 * Queue a packet. Start transmission if not active. 435 * Compression happens in slintr(); if we do it here, IP TOS 436 * will cause us to not compress "background" packets, because 437 * ordering gets trashed. It can be done for all packets in slintr(). 438 */ 439static int 440sloutput(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst, 441 struct rtentry *rtp) 442{ 443 struct sl_softc *sc = ifp->if_softc; 444 struct ip *ip; 445 struct ifqueue *ifq = NULL; 446 int s, error; 447 ALTQ_DECL(struct altq_pktattr pktattr;) 448 449 IFQ_CLASSIFY(&ifp->if_snd, m, dst->sa_family, &pktattr); 450 451 /* 452 * `Cannot happen' (see slioctl). Someday we will extend 453 * the line protocol to support other address families. 454 */ 455 if (dst->sa_family != AF_INET) { 456 printf("%s: af%d not supported\n", sc->sc_if.if_xname, 457 dst->sa_family); 458 m_freem(m); 459 sc->sc_if.if_noproto++; 460 return EAFNOSUPPORT; 461 } 462 463 if (sc->sc_ttyp == NULL) { 464 m_freem(m); 465 return ENETDOWN; /* sort of */ 466 } 467 if ((sc->sc_ttyp->t_state & TS_CARR_ON) == 0 && 468 (sc->sc_ttyp->t_cflag & CLOCAL) == 0) { 469 m_freem(m); 470 printf("%s: no carrier and not local\n", sc->sc_if.if_xname); 471 return EHOSTUNREACH; 472 } 473 ip = mtod(m, struct ip *); 474#ifdef INET 475 if (sc->sc_if.if_flags & SC_NOICMP && ip->ip_p == IPPROTO_ICMP) { 476 m_freem(m); 477 return ENETRESET; /* XXX ? */ 478 } 479#endif 480 481 s = spltty(); 482 if (sc->sc_oqlen && sc->sc_ttyp->t_outq.c_cc == sc->sc_oqlen) { 483 struct bintime bt; 484 485 /* if output's been stalled for too long, and restart */ 486 getbinuptime(&bt); 487 bintime_sub(&bt, &sc->sc_lastpacket); 488 if (bt.sec > 0) { 489 sc->sc_otimeout++; 490 slstart(sc->sc_ttyp); 491 } 492 } 493 splx(s); 494 495 s = splnet(); 496#ifdef INET 497 if ((ip->ip_tos & IPTOS_LOWDELAY) != 0) 498 ifq = &sc->sc_fastq; 499#endif 500 if ((error = ifq_enqueue2(ifp, ifq, m ALTQ_COMMA 501 ALTQ_DECL(&pktattr))) != 0) { 502 splx(s); 503 return error; 504 } 505 getbinuptime(&sc->sc_lastpacket); 506 splx(s); 507 508 s = spltty(); 509 if ((sc->sc_oqlen = sc->sc_ttyp->t_outq.c_cc) == 0) 510 slstart(sc->sc_ttyp); 511 splx(s); 512 513 return 0; 514} 515 516/* 517 * Start output on interface. Get another datagram 518 * to send from the interface queue and map it to 519 * the interface before starting output. 520 */ 521static int 522slstart(struct tty *tp) 523{ 524 struct sl_softc *sc = tp->t_sc; 525 526 /* 527 * If there is more in the output queue, just send it now. 528 * We are being called in lieu of ttstart and must do what 529 * it would. 530 */ 531 if (tp->t_outq.c_cc != 0) { 532 (*tp->t_oproc)(tp); 533 if (tp->t_outq.c_cc > SLIP_HIWAT) 534 return 0; 535 } 536 537 /* 538 * This happens briefly when the line shuts down. 539 */ 540 if (sc == NULL) 541 return 0; 542 softint_schedule(sc->sc_si); 543 return 0; 544} 545 546/* 547 * Copy data buffer to mbuf chain; add ifnet pointer. 548 */ 549static struct mbuf * 550sl_btom(struct sl_softc *sc, int len) 551{ 552 struct mbuf *m; 553 554 /* 555 * Allocate a new input buffer and swap. 556 */ 557 m = sc->sc_mbuf; 558 MGETHDR(sc->sc_mbuf, M_DONTWAIT, MT_DATA); 559 if (sc->sc_mbuf == NULL) { 560 sc->sc_mbuf = m; 561 return NULL; 562 } 563 MCLGET(sc->sc_mbuf, M_DONTWAIT); 564 if ((sc->sc_mbuf->m_flags & M_EXT) == 0) { 565 m_freem(sc->sc_mbuf); 566 sc->sc_mbuf = m; 567 return NULL; 568 } 569 sc->sc_ep = (u_char *)sc->sc_mbuf->m_ext.ext_buf + 570 sc->sc_mbuf->m_ext.ext_size; 571 572 m->m_data = sc->sc_pktstart; 573 574 m->m_pkthdr.len = m->m_len = len; 575 m->m_pkthdr.rcvif = &sc->sc_if; 576 return m; 577} 578 579/* 580 * tty interface receiver interrupt. 581 */ 582static int 583slinput(int c, struct tty *tp) 584{ 585 struct sl_softc *sc; 586 struct mbuf *m; 587 int len; 588 589 tk_nin++; 590 sc = (struct sl_softc *)tp->t_sc; 591 if (sc == NULL) 592 return 0; 593 if ((c & TTY_ERRORMASK) || ((tp->t_state & TS_CARR_ON) == 0 && 594 (tp->t_cflag & CLOCAL) == 0)) { 595 sc->sc_flags |= SC_ERROR; 596 return 0; 597 } 598 c &= TTY_CHARMASK; 599 600 ++sc->sc_if.if_ibytes; 601 602 if (sc->sc_if.if_flags & IFF_DEBUG) { 603 if (c == ABT_ESC) { 604 /* 605 * If we have a previous abort, see whether 606 * this one is within the time limit. 607 */ 608 if (sc->sc_abortcount && 609 time_second >= sc->sc_starttime + ABT_WINDOW) 610 sc->sc_abortcount = 0; 611 /* 612 * If we see an abort after "idle" time, count it; 613 * record when the first abort escape arrived. 614 */ 615 if (time_second >= sc->sc_lasttime + ABT_IDLE) { 616 if (++sc->sc_abortcount == 1) 617 sc->sc_starttime = time_second; 618 if (sc->sc_abortcount >= ABT_COUNT) { 619 slclose(tp, 0); 620 return 0; 621 } 622 } 623 } else 624 sc->sc_abortcount = 0; 625 sc->sc_lasttime = time_second; 626 } 627 628 switch (c) { 629 630 case TRANS_FRAME_ESCAPE: 631 if (sc->sc_escape) 632 c = FRAME_ESCAPE; 633 break; 634 635 case TRANS_FRAME_END: 636 if (sc->sc_escape) 637 c = FRAME_END; 638 break; 639 640 case FRAME_ESCAPE: 641 sc->sc_escape = 1; 642 return 0; 643 644 case FRAME_END: 645 if (sc->sc_flags & SC_ERROR) { 646 sc->sc_flags &= ~SC_ERROR; 647 goto newpack; 648 } 649 len = sc->sc_mp - sc->sc_pktstart; 650 if (len < 3) 651 /* less than min length packet - ignore */ 652 goto newpack; 653 654 m = sl_btom(sc, len); 655 if (m == NULL) 656 goto error; 657 658 IF_ENQUEUE(&sc->sc_inq, m); 659 softint_schedule(sc->sc_si); 660 goto newpack; 661 } 662 if (sc->sc_mp < sc->sc_ep) { 663 *sc->sc_mp++ = c; 664 sc->sc_escape = 0; 665 return 0; 666 } 667 668 /* can't put lower; would miss an extra frame */ 669 sc->sc_flags |= SC_ERROR; 670 671error: 672 sc->sc_if.if_ierrors++; 673newpack: 674 sc->sc_mp = sc->sc_pktstart = (u_char *)sc->sc_mbuf->m_ext.ext_buf + 675 BUFOFFSET; 676 sc->sc_escape = 0; 677 678 return 0; 679} 680 681static void 682slintr(void *arg) 683{ 684 struct sl_softc *sc = arg; 685 struct tty *tp = sc->sc_ttyp; 686 struct mbuf *m; 687 int s, len; 688 u_char *pktstart; 689#ifdef INET 690 u_char c; 691#endif 692#if NBPFILTER > 0 693 u_char chdr[CHDR_LEN]; 694#endif 695 696 KASSERT(tp != NULL); 697 698 /* 699 * Output processing loop. 700 */ 701 mutex_enter(softnet_lock); 702 for (;;) { 703#ifdef INET 704 struct ip *ip; 705#endif 706 struct mbuf *m2; 707#if NBPFILTER > 0 708 struct mbuf *bpf_m; 709#endif 710 711 /* 712 * Do not remove the packet from the queue if it 713 * doesn't look like it will fit into the current 714 * serial output queue. With a packet full of 715 * escapes, this could be as bad as MTU*2+2. 716 */ 717 s = spltty(); 718 if (tp->t_outq.c_cn - tp->t_outq.c_cc < 719 2 * sc->sc_if.if_mtu + 2) { 720 splx(s); 721 break; 722 } 723 splx(s); 724 725 /* 726 * Get a packet and send it to the interface. 727 */ 728 s = splnet(); 729 IF_DEQUEUE(&sc->sc_fastq, m); 730 if (m) 731 sc->sc_if.if_omcasts++; /* XXX */ 732 else 733 IFQ_DEQUEUE(&sc->sc_if.if_snd, m); 734 splx(s); 735 736 if (m == NULL) 737 break; 738 739 /* 740 * We do the header compression here rather than in 741 * sloutput() because the packets will be out of order 742 * if we are using TOS queueing, and the connection 743 * ID compression will get munged when this happens. 744 */ 745#if NBPFILTER > 0 746 if (sc->sc_if.if_bpf) { 747 /* 748 * We need to save the TCP/IP header before 749 * it's compressed. To avoid complicated 750 * code, we just make a deep copy of the 751 * entire packet (since this is a serial 752 * line, packets should be short and/or the 753 * copy should be negligible cost compared 754 * to the packet transmission time). 755 */ 756 bpf_m = m_dup(m, 0, M_COPYALL, M_DONTWAIT); 757 } else 758 bpf_m = NULL; 759#endif 760#ifdef INET 761 if ((ip = mtod(m, struct ip *))->ip_p == IPPROTO_TCP) { 762 if (sc->sc_if.if_flags & SC_COMPRESS) 763 *mtod(m, u_char *) |= 764 sl_compress_tcp(m, ip, &sc->sc_comp, 1); 765 } 766#endif 767#if NBPFILTER > 0 768 if (sc->sc_if.if_bpf && bpf_m != NULL) 769 bpf_mtap_sl_out(sc->sc_if.if_bpf, mtod(m, u_char *), 770 bpf_m); 771#endif 772 getbinuptime(&sc->sc_lastpacket); 773 774 s = spltty(); 775 776 /* 777 * The extra FRAME_END will start up a new packet, 778 * and thus will flush any accumulated garbage. We 779 * do this whenever the line may have been idle for 780 * some time. 781 */ 782 if (tp->t_outq.c_cc == 0) { 783 sc->sc_if.if_obytes++; 784 (void)putc(FRAME_END, &tp->t_outq); 785 } 786 787 while (m) { 788 u_char *bp, *cp, *ep; 789 790 bp = cp = mtod(m, u_char *); 791 ep = cp + m->m_len; 792 while (cp < ep) { 793 /* 794 * Find out how many bytes in the 795 * string we can handle without 796 * doing something special. 797 */ 798 while (cp < ep) { 799 switch (*cp++) { 800 case FRAME_ESCAPE: 801 case FRAME_END: 802 cp--; 803 goto out; 804 } 805 } 806 out: 807 if (cp > bp) { 808 /* 809 * Put N characters at once 810 * into the tty output queue. 811 */ 812 if (b_to_q(bp, cp - bp, &tp->t_outq)) 813 break; 814 sc->sc_if.if_obytes += cp - bp; 815 } 816 /* 817 * If there are characters left in 818 * the mbuf, the first one must be 819 * special.. Put it out in a different 820 * form. 821 */ 822 if (cp < ep) { 823 if (putc(FRAME_ESCAPE, &tp->t_outq)) 824 break; 825 if (putc(*cp++ == FRAME_ESCAPE ? 826 TRANS_FRAME_ESCAPE : 827 TRANS_FRAME_END, 828 &tp->t_outq)) { 829 (void)unputc(&tp->t_outq); 830 break; 831 } 832 sc->sc_if.if_obytes += 2; 833 } 834 bp = cp; 835 } 836 MFREE(m, m2); 837 m = m2; 838 } 839 840 if (putc(FRAME_END, &tp->t_outq)) { 841 /* 842 * Not enough room. Remove a char to make 843 * room and end the packet normally. If 844 * you get many collisions (more than one 845 * or two a day), you probably do not have 846 * enough clists and you should increase 847 * "nclist" in param.c 848 */ 849 (void)unputc(&tp->t_outq); 850 (void)putc(FRAME_END, &tp->t_outq); 851 sc->sc_if.if_collisions++; 852 } else { 853 sc->sc_if.if_obytes++; 854 sc->sc_if.if_opackets++; 855 } 856 857 /* 858 * We now have characters in the output queue, 859 * kick the serial port. 860 */ 861 (*tp->t_oproc)(tp); 862 splx(s); 863 } 864 865 /* 866 * Input processing loop. 867 */ 868 for (;;) { 869 s = spltty(); 870 IF_DEQUEUE(&sc->sc_inq, m); 871 splx(s); 872 if (m == NULL) 873 break; 874 pktstart = mtod(m, u_char *); 875 len = m->m_pkthdr.len; 876#if NBPFILTER > 0 877 if (sc->sc_if.if_bpf) { 878 /* 879 * Save the compressed header, so we 880 * can tack it on later. Note that we 881 * will end up copying garbage in some 882 * cases but this is okay. We remember 883 * where the buffer started so we can 884 * compute the new header length. 885 */ 886 memcpy(chdr, pktstart, CHDR_LEN); 887 } 888#endif /* NBPFILTER > 0 */ 889#ifdef INET 890 if ((c = (*pktstart & 0xf0)) != (IPVERSION << 4)) { 891 if (c & 0x80) 892 c = TYPE_COMPRESSED_TCP; 893 else if (c == TYPE_UNCOMPRESSED_TCP) 894 *pktstart &= 0x4f; /* XXX */ 895 /* 896 * We've got something that's not an IP 897 * packet. If compression is enabled, 898 * try to decompress it. Otherwise, if 899 * `auto-enable' compression is on and 900 * it's a reasonable packet, decompress 901 * it and then enable compression. 902 * Otherwise, drop it. 903 */ 904 if (sc->sc_if.if_flags & SC_COMPRESS) { 905 len = sl_uncompress_tcp(&pktstart, len, 906 (u_int)c, &sc->sc_comp); 907 if (len <= 0) { 908 m_freem(m); 909 continue; 910 } 911 } else if ((sc->sc_if.if_flags & SC_AUTOCOMP) && 912 c == TYPE_UNCOMPRESSED_TCP && len >= 40) { 913 len = sl_uncompress_tcp(&pktstart, len, 914 (u_int)c, &sc->sc_comp); 915 if (len <= 0) { 916 m_freem(m); 917 continue; 918 } 919 sc->sc_if.if_flags |= SC_COMPRESS; 920 } else { 921 m_freem(m); 922 continue; 923 } 924 } 925#endif 926 m->m_data = (void *) pktstart; 927 m->m_pkthdr.len = m->m_len = len; 928#if NBPFILTER > 0 929 if (sc->sc_if.if_bpf) { 930 bpf_mtap_sl_in(sc->sc_if.if_bpf, chdr, &m); 931 if (m == NULL) 932 continue; 933 } 934#endif /* NBPFILTER > 0 */ 935 /* 936 * If the packet will fit into a single 937 * header mbuf, copy it into one, to save 938 * memory. 939 */ 940 if (m->m_pkthdr.len < MHLEN) { 941 struct mbuf *n; 942 int pktlen; 943 944 MGETHDR(n, M_DONTWAIT, MT_DATA); 945 pktlen = m->m_pkthdr.len; 946 M_MOVE_PKTHDR(n, m); 947 memcpy(mtod(n, void *), mtod(m, void *), pktlen); 948 n->m_len = m->m_len; 949 m_freem(m); 950 m = n; 951 } 952 953 sc->sc_if.if_ipackets++; 954 getbinuptime(&sc->sc_lastpacket); 955 956#ifdef INET 957 s = splnet(); 958 if (IF_QFULL(&ipintrq)) { 959 IF_DROP(&ipintrq); 960 sc->sc_if.if_ierrors++; 961 sc->sc_if.if_iqdrops++; 962 m_freem(m); 963 } else { 964 IF_ENQUEUE(&ipintrq, m); 965 schednetisr(NETISR_IP); 966 } 967 splx(s); 968#endif 969 } 970 mutex_exit(softnet_lock); 971} 972 973/* 974 * Process an ioctl request. 975 */ 976static int 977slioctl(struct ifnet *ifp, u_long cmd, void *data) 978{ 979 struct ifaddr *ifa = (struct ifaddr *)data; 980 struct ifreq *ifr = (struct ifreq *)data; 981 int s = splnet(), error = 0; 982 struct sl_softc *sc = ifp->if_softc; 983 struct ppp_stats *psp; 984 struct ppp_comp_stats *pcp; 985 986 switch (cmd) { 987 988 case SIOCSIFADDR: 989 if (ifa->ifa_addr->sa_family == AF_INET) 990 ifp->if_flags |= IFF_UP; 991 else 992 error = EAFNOSUPPORT; 993 break; 994 995 case SIOCSIFDSTADDR: 996 if (ifa->ifa_addr->sa_family != AF_INET) 997 error = EAFNOSUPPORT; 998 break; 999 1000 case SIOCSIFMTU: 1001 if ((ifr->ifr_mtu < 3) || (ifr->ifr_mtu > SLMAX)) { 1002 error = EINVAL; 1003 break; 1004 } 1005 /*FALLTHROUGH*/ 1006 case SIOCGIFMTU: 1007 if ((error = ifioctl_common(&sc->sc_if, cmd, data)) == ENETRESET) 1008 error = 0; 1009 break; 1010 1011 case SIOCADDMULTI: 1012 case SIOCDELMULTI: 1013 if (ifr == 0) { 1014 error = EAFNOSUPPORT; /* XXX */ 1015 break; 1016 } 1017 switch (ifreq_getaddr(cmd, ifr)->sa_family) { 1018 1019#ifdef INET 1020 case AF_INET: 1021 break; 1022#endif 1023 1024 default: 1025 error = EAFNOSUPPORT; 1026 break; 1027 } 1028 break; 1029 1030 case SIOCGPPPSTATS: 1031 psp = &((struct ifpppstatsreq *) data)->stats; 1032 (void)memset(psp, 0, sizeof(*psp)); 1033 psp->p.ppp_ibytes = sc->sc_if.if_ibytes; 1034 psp->p.ppp_ipackets = sc->sc_if.if_ipackets; 1035 psp->p.ppp_ierrors = sc->sc_if.if_ierrors; 1036 psp->p.ppp_obytes = sc->sc_if.if_obytes; 1037 psp->p.ppp_opackets = sc->sc_if.if_opackets; 1038 psp->p.ppp_oerrors = sc->sc_if.if_oerrors; 1039#ifdef INET 1040 psp->vj.vjs_packets = sc->sc_comp.sls_packets; 1041 psp->vj.vjs_compressed = sc->sc_comp.sls_compressed; 1042 psp->vj.vjs_searches = sc->sc_comp.sls_searches; 1043 psp->vj.vjs_misses = sc->sc_comp.sls_misses; 1044 psp->vj.vjs_uncompressedin = sc->sc_comp.sls_uncompressedin; 1045 psp->vj.vjs_compressedin = sc->sc_comp.sls_compressedin; 1046 psp->vj.vjs_errorin = sc->sc_comp.sls_errorin; 1047 psp->vj.vjs_tossed = sc->sc_comp.sls_tossed; 1048#endif 1049 break; 1050 1051 case SIOCGPPPCSTATS: 1052 pcp = &((struct ifpppcstatsreq *) data)->stats; 1053 (void)memset(pcp, 0, sizeof(*pcp)); 1054 break; 1055 1056 default: 1057 error = EINVAL; 1058 } 1059 splx(s); 1060 return error; 1061} 1062