if_sl.c revision 1.72
1/* $NetBSD: if_sl.c,v 1.72 2001/01/17 00:30:51 thorpej 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. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 * 35 * @(#)if_sl.c 8.9 (Berkeley) 1/9/95 36 */ 37 38/* 39 * Serial Line interface 40 * 41 * Rick Adams 42 * Center for Seismic Studies 43 * 1300 N 17th Street, Suite 1450 44 * Arlington, Virginia 22209 45 * (703)276-7900 46 * rick@seismo.ARPA 47 * seismo!rick 48 * 49 * Pounded on heavily by Chris Torek (chris@mimsy.umd.edu, umcp-cs!chris). 50 * N.B.: this belongs in netinet, not net, the way it stands now. 51 * Should have a link-layer type designation, but wouldn't be 52 * backwards-compatible. 53 * 54 * Converted to 4.3BSD Beta by Chris Torek. 55 * Other changes made at Berkeley, based in part on code by Kirk Smith. 56 * W. Jolitz added slip abort. 57 * 58 * Hacked almost beyond recognition by Van Jacobson (van@helios.ee.lbl.gov). 59 * Added priority queuing for "interactive" traffic; hooks for TCP 60 * header compression; ICMP filtering (at 2400 baud, some cretin 61 * pinging you can use up all your bandwidth). Made low clist behavior 62 * more robust and slightly less likely to hang serial line. 63 * Sped up a bunch of things. 64 */ 65 66#include "sl.h" 67#if NSL > 0 68 69#include "opt_inet.h" 70#include "bpfilter.h" 71 72#include <sys/param.h> 73#include <sys/proc.h> 74#include <sys/malloc.h> 75#include <sys/mbuf.h> 76#include <sys/buf.h> 77#include <sys/dkstat.h> 78#include <sys/socket.h> 79#include <sys/ioctl.h> 80#include <sys/file.h> 81#include <sys/conf.h> 82#include <sys/tty.h> 83#include <sys/kernel.h> 84#if __NetBSD__ 85#include <sys/systm.h> 86#endif 87 88#include <machine/cpu.h> 89#ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 90#include <machine/intr.h> 91#endif 92 93#include <net/if.h> 94#include <net/if_types.h> 95#include <net/netisr.h> 96#include <net/route.h> 97 98#ifdef INET 99#include <netinet/in.h> 100#include <netinet/in_systm.h> 101#include <netinet/in_var.h> 102#include <netinet/ip.h> 103#else 104#error Slip without inet? 105#endif 106 107#include <net/slcompress.h> 108#include <net/if_slvar.h> 109#include <net/slip.h> 110 111#if NBPFILTER > 0 112#include <sys/time.h> 113#include <net/bpf.h> 114#endif 115 116/* 117 * SLMAX is a hard limit on input packet size. To simplify the code 118 * and improve performance, we require that packets fit in an mbuf 119 * cluster, and if we get a compressed packet, there's enough extra 120 * room to expand the header into a max length tcp/ip header (128 121 * bytes). So, SLMAX can be at most 122 * MCLBYTES - 128 123 * 124 * SLMTU is a hard limit on output packet size. To insure good 125 * interactive response, SLMTU wants to be the smallest size that 126 * amortizes the header cost. (Remember that even with 127 * type-of-service queuing, we have to wait for any in-progress 128 * packet to finish. I.e., we wait, on the average, 1/2 * mtu / 129 * cps, where cps is the line speed in characters per second. 130 * E.g., 533ms wait for a 1024 byte MTU on a 9600 baud line. The 131 * average compressed header size is 6-8 bytes so any MTU > 90 132 * bytes will give us 90% of the line bandwidth. A 100ms wait is 133 * tolerable (500ms is not), so want an MTU around 296. (Since TCP 134 * will send 256 byte segments (to allow for 40 byte headers), the 135 * typical packet size on the wire will be around 260 bytes). In 136 * 4.3tahoe+ systems, we can set an MTU in a route so we do that & 137 * leave the interface MTU relatively high (so we don't IP fragment 138 * when acting as a gateway to someone using a stupid MTU). 139 * 140 * Similar considerations apply to SLIP_HIWAT: It's the amount of 141 * data that will be queued 'downstream' of us (i.e., in clists 142 * waiting to be picked up by the tty output interrupt). If we 143 * queue a lot of data downstream, it's immune to our t.o.s. queuing. 144 * E.g., if SLIP_HIWAT is 1024, the interactive traffic in mixed 145 * telnet/ftp will see a 1 sec wait, independent of the mtu (the 146 * wait is dependent on the ftp window size but that's typically 147 * 1k - 4k). So, we want SLIP_HIWAT just big enough to amortize 148 * the cost (in idle time on the wire) of the tty driver running 149 * off the end of its clists & having to call back slstart for a 150 * new packet. For a tty interface with any buffering at all, this 151 * cost will be zero. Even with a totally brain dead interface (like 152 * the one on a typical workstation), the cost will be <= 1 character 153 * time. So, setting SLIP_HIWAT to ~100 guarantees that we'll lose 154 * at most 1% while maintaining good interactive response. 155 */ 156#define BUFOFFSET (128+sizeof(struct ifnet **)+SLIP_HDRLEN) 157#define SLMAX (MCLBYTES - BUFOFFSET) 158#define SLBUFSIZE (SLMAX + BUFOFFSET) 159#ifndef SLMTU 160#define SLMTU 296 161#endif 162#if (SLMTU < 3) 163#error SLMTU way too small. 164#endif 165#define SLIP_HIWAT roundup(50,CBSIZE) 166#ifndef __NetBSD__ /* XXX - cgd */ 167#define CLISTRESERVE 1024 /* Can't let clists get too low */ 168#endif /* !__NetBSD__ */ 169 170/* 171 * SLIP ABORT ESCAPE MECHANISM: 172 * (inspired by HAYES modem escape arrangement) 173 * 1sec escape 1sec escape 1sec escape { 1sec escape 1sec escape } 174 * within window time signals a "soft" exit from slip mode by remote end 175 * if the IFF_DEBUG flag is on. 176 */ 177#define ABT_ESC '\033' /* can't be t_intr - distant host must know it*/ 178#define ABT_IDLE 1 /* in seconds - idle before an escape */ 179#define ABT_COUNT 3 /* count of escapes for abort */ 180#define ABT_WINDOW (ABT_COUNT*2+2) /* in seconds - time to count */ 181 182struct sl_softc sl_softc[NSL]; 183 184#define FRAME_END 0xc0 /* Frame End */ 185#define FRAME_ESCAPE 0xdb /* Frame Esc */ 186#define TRANS_FRAME_END 0xdc /* transposed frame end */ 187#define TRANS_FRAME_ESCAPE 0xdd /* transposed frame esc */ 188 189#ifndef __HAVE_GENERIC_SOFT_INTERRUPTS 190void slnetisr(void); 191#endif 192void slintr(void *); 193 194static int slinit __P((struct sl_softc *)); 195static struct mbuf *sl_btom __P((struct sl_softc *, int)); 196 197/* 198 * Called from boot code to establish sl interfaces. 199 */ 200void 201slattach() 202{ 203 struct sl_softc *sc; 204 int i = 0; 205 206 for (sc = sl_softc; i < NSL; sc++) { 207 sc->sc_unit = i; /* XXX */ 208 sprintf(sc->sc_if.if_xname, "sl%d", i++); 209 sc->sc_if.if_softc = sc; 210 sc->sc_if.if_mtu = SLMTU; 211 sc->sc_if.if_flags = 212 IFF_POINTOPOINT | SC_AUTOCOMP | IFF_MULTICAST; 213 sc->sc_if.if_type = IFT_SLIP; 214 sc->sc_if.if_ioctl = slioctl; 215 sc->sc_if.if_output = sloutput; 216 sc->sc_if.if_dlt = DLT_SLIP; 217 sc->sc_fastq.ifq_maxlen = 32; 218 IFQ_SET_READY(&sc->sc_if.if_snd); 219 if_attach(&sc->sc_if); 220 if_alloc_sadl(&sc->sc_if); 221#if NBPFILTER > 0 222 bpfattach(&sc->sc_if, DLT_SLIP, SLIP_HDRLEN); 223#endif 224 } 225} 226 227static int 228slinit(sc) 229 struct sl_softc *sc; 230{ 231 232 if (sc->sc_mbuf == NULL) { 233 MGETHDR(sc->sc_mbuf, M_WAIT, MT_DATA); 234 MCLGET(sc->sc_mbuf, M_WAIT); 235 } 236 sc->sc_ep = (u_char *) sc->sc_mbuf->m_ext.ext_buf + 237 sc->sc_mbuf->m_ext.ext_size; 238 sc->sc_mp = sc->sc_pktstart = (u_char *) sc->sc_mbuf->m_ext.ext_buf + 239 BUFOFFSET; 240 241 sl_compress_init(&sc->sc_comp); 242 243 return (1); 244} 245 246/* 247 * Line specific open routine. 248 * Attach the given tty to the first available sl unit. 249 */ 250/* ARGSUSED */ 251int 252slopen(dev, tp) 253 dev_t dev; 254 struct tty *tp; 255{ 256 struct proc *p = curproc; /* XXX */ 257 struct sl_softc *sc; 258 int nsl; 259 int error; 260 int s; 261 262 if ((error = suser(p->p_ucred, &p->p_acflag)) != 0) 263 return (error); 264 265 if (tp->t_linesw && (tp->t_linesw->l_no == SLIPDISC)) 266 return (0); 267 268 for (nsl = NSL, sc = sl_softc; --nsl >= 0; sc++) 269 if (sc->sc_ttyp == NULL) { 270#ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 271 sc->sc_si = softintr_establish(IPL_SOFTNET, 272 slintr, sc); 273 if (sc->sc_si == NULL) 274 return (ENOMEM); 275#endif 276 if (slinit(sc) == 0) { 277#ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 278 softintr_disestablish(sc->sc_si); 279#endif 280 return (ENOBUFS); 281 } 282 tp->t_sc = (caddr_t)sc; 283 sc->sc_ttyp = tp; 284 sc->sc_if.if_baudrate = tp->t_ospeed; 285 s = spltty(); 286 tp->t_state |= TS_ISOPEN | TS_XCLUDE; 287 splx(s); 288 ttyflush(tp, FREAD | FWRITE); 289#ifdef __NetBSD__ 290 /* 291 * make sure tty output queue is large enough 292 * to hold a full-sized packet (including frame 293 * end, and a possible extra frame end). full-sized 294 * packet occupies a max of 2*SLMAX bytes (because 295 * of possible escapes), and add two on for frame 296 * ends. 297 */ 298 s = spltty(); 299 if (tp->t_outq.c_cn < 2*SLMAX+2) { 300 sc->sc_oldbufsize = tp->t_outq.c_cn; 301 sc->sc_oldbufquot = tp->t_outq.c_cq != 0; 302 303 clfree(&tp->t_outq); 304 error = clalloc(&tp->t_outq, 2*SLMAX+2, 0); 305 if (error) { 306 splx(s); 307#ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 308 softintr_disestablish(sc->sc_si); 309#endif 310 return(error); 311 } 312 } else 313 sc->sc_oldbufsize = sc->sc_oldbufquot = 0; 314 splx(s); 315#endif /* __NetBSD__ */ 316 return (0); 317 } 318 return (ENXIO); 319} 320 321/* 322 * Line specific close routine. 323 * Detach the tty from the sl unit. 324 */ 325void 326slclose(tp) 327 struct tty *tp; 328{ 329 struct sl_softc *sc; 330 int s; 331 332 ttywflush(tp); 333 sc = tp->t_sc; 334 335 if (sc != NULL) { 336#ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 337 softintr_disestablish(sc->sc_si); 338#endif 339 s = splnet(); 340 if_down(&sc->sc_if); 341 IF_PURGE(&sc->sc_fastq); 342 splx(s); 343 344 s = spltty(); 345 tp->t_linesw = linesw[0]; /* default line disc. */ 346 tp->t_state = 0; 347 348 sc->sc_ttyp = NULL; 349 tp->t_sc = NULL; 350 351 m_freem(sc->sc_mbuf); 352 sc->sc_mbuf = NULL; 353 sc->sc_ep = sc->sc_mp = sc->sc_pktstart = NULL; 354 IF_PURGE(&sc->sc_inq); 355 356 /* 357 * If necessary, install a new outq buffer of the 358 * appropriate size. 359 */ 360 if (sc->sc_oldbufsize != 0) { 361 clfree(&tp->t_outq); 362 clalloc(&tp->t_outq, sc->sc_oldbufsize, 363 sc->sc_oldbufquot); 364 } 365 splx(s); 366 } 367} 368 369/* 370 * Line specific (tty) ioctl routine. 371 * Provide a way to get the sl unit number. 372 */ 373/* ARGSUSED */ 374int 375sltioctl(tp, cmd, data, flag) 376 struct tty *tp; 377 u_long cmd; 378 caddr_t data; 379 int flag; 380{ 381 struct sl_softc *sc = (struct sl_softc *)tp->t_sc; 382 383 switch (cmd) { 384 case SLIOCGUNIT: 385 *(int *)data = sc->sc_unit; /* XXX */ 386 break; 387 388 default: 389 return (-1); 390 } 391 return (0); 392} 393 394/* 395 * Queue a packet. Start transmission if not active. 396 * Compression happens in slintr(); if we do it here, IP TOS 397 * will cause us to not compress "background" packets, because 398 * ordering gets trashed. It can be done for all packets in slintr(). 399 */ 400int 401sloutput(ifp, m, dst, rtp) 402 struct ifnet *ifp; 403 struct mbuf *m; 404 struct sockaddr *dst; 405 struct rtentry *rtp; 406{ 407 struct sl_softc *sc = ifp->if_softc; 408 struct ip *ip; 409 int s, error; 410 ALTQ_DECL(struct altq_pktattr pktattr;) 411 412 IFQ_CLASSIFY(&ifp->if_snd, m, dst->sa_family, &pktattr); 413 414 /* 415 * `Cannot happen' (see slioctl). Someday we will extend 416 * the line protocol to support other address families. 417 */ 418 if (dst->sa_family != AF_INET) { 419 printf("%s: af%d not supported\n", sc->sc_if.if_xname, 420 dst->sa_family); 421 m_freem(m); 422 sc->sc_if.if_noproto++; 423 return (EAFNOSUPPORT); 424 } 425 426 if (sc->sc_ttyp == NULL) { 427 m_freem(m); 428 return (ENETDOWN); /* sort of */ 429 } 430 if ((sc->sc_ttyp->t_state & TS_CARR_ON) == 0 && 431 (sc->sc_ttyp->t_cflag & CLOCAL) == 0) { 432 m_freem(m); 433 printf("%s: no carrier and not local\n", sc->sc_if.if_xname); 434 return (EHOSTUNREACH); 435 } 436 ip = mtod(m, struct ip *); 437 if (sc->sc_if.if_flags & SC_NOICMP && ip->ip_p == IPPROTO_ICMP) { 438 m_freem(m); 439 return (ENETRESET); /* XXX ? */ 440 } 441 442 s = spltty(); 443 if (sc->sc_oqlen && sc->sc_ttyp->t_outq.c_cc == sc->sc_oqlen) { 444 struct timeval tv; 445 446 /* if output's been stalled for too long, and restart */ 447 timersub(&time, &sc->sc_if.if_lastchange, &tv); 448 if (tv.tv_sec > 0) { 449 sc->sc_otimeout++; 450 slstart(sc->sc_ttyp); 451 } 452 } 453 splx(s); 454 455 s = splnet(); 456 if ((ip->ip_tos & IPTOS_LOWDELAY) != 0 457#ifdef ALTQ 458 && ALTQ_IS_ENABLED(&ifp->if_snd) == 0 459#endif 460 ) { 461 if (IF_QFULL(&sc->sc_fastq)) { 462 IF_DROP(&sc->sc_fastq); 463 m_freem(m); 464 error = ENOBUFS; 465 } else { 466 IF_ENQUEUE(&sc->sc_fastq, m); 467 error = 0; 468 } 469 } else 470 IFQ_ENQUEUE(&ifp->if_snd, m, &pktattr, error); 471 if (error) { 472 splx(s); 473 ifp->if_oerrors++; 474 return (error); 475 } 476 sc->sc_if.if_lastchange = time; 477 splx(s); 478 479 s = spltty(); 480 if ((sc->sc_oqlen = sc->sc_ttyp->t_outq.c_cc) == 0) 481 slstart(sc->sc_ttyp); 482 splx(s); 483 484 return (0); 485} 486 487/* 488 * Start output on interface. Get another datagram 489 * to send from the interface queue and map it to 490 * the interface before starting output. 491 */ 492void 493slstart(tp) 494 struct tty *tp; 495{ 496 struct sl_softc *sc = tp->t_sc; 497 498 /* 499 * If there is more in the output queue, just send it now. 500 * We are being called in lieu of ttstart and must do what 501 * it would. 502 */ 503 if (tp->t_outq.c_cc != 0) { 504 (*tp->t_oproc)(tp); 505 if (tp->t_outq.c_cc > SLIP_HIWAT) 506 return; 507 } 508 509 /* 510 * This happens briefly when the line shuts down. 511 */ 512 if (sc == NULL) 513 return; 514#ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 515 softintr_schedule(sc->sc_si); 516#else 517 { 518 int s = splimp(); 519 schednetisr(NETISR_SLIP); 520 splx(s); 521 } 522#endif 523} 524 525/* 526 * Copy data buffer to mbuf chain; add ifnet pointer. 527 */ 528static struct mbuf * 529sl_btom(sc, len) 530 struct sl_softc *sc; 531 int len; 532{ 533 struct mbuf *m; 534 535 MGETHDR(m, M_DONTWAIT, MT_DATA); 536 if (m == NULL) 537 return (NULL); 538 539 /* 540 * Allocate a new input buffer and swap. 541 */ 542 m = sc->sc_mbuf; 543 MGETHDR(sc->sc_mbuf, M_DONTWAIT, MT_DATA); 544 if (sc->sc_mbuf == NULL) { 545 sc->sc_mbuf = m; 546 return (NULL); 547 } 548 MCLGET(sc->sc_mbuf, M_DONTWAIT); 549 if ((sc->sc_mbuf->m_flags & M_EXT) == 0) { 550 m_freem(sc->sc_mbuf); 551 sc->sc_mbuf = m; 552 return (NULL); 553 } 554 sc->sc_ep = (u_char *) sc->sc_mbuf->m_ext.ext_buf + 555 sc->sc_mbuf->m_ext.ext_size; 556 557 m->m_data = sc->sc_pktstart; 558 559 m->m_pkthdr.len = m->m_len = len; 560 m->m_pkthdr.rcvif = &sc->sc_if; 561 return (m); 562} 563 564/* 565 * tty interface receiver interrupt. 566 */ 567void 568slinput(c, tp) 569 int c; 570 struct tty *tp; 571{ 572 struct sl_softc *sc; 573 struct mbuf *m; 574 int len; 575 576 tk_nin++; 577 sc = (struct sl_softc *)tp->t_sc; 578 if (sc == NULL) 579 return; 580 if ((c & TTY_ERRORMASK) || ((tp->t_state & TS_CARR_ON) == 0 && 581 (tp->t_cflag & CLOCAL) == 0)) { 582 sc->sc_flags |= SC_ERROR; 583 return; 584 } 585 c &= TTY_CHARMASK; 586 587 ++sc->sc_if.if_ibytes; 588 589 if (sc->sc_if.if_flags & IFF_DEBUG) { 590 if (c == ABT_ESC) { 591 /* 592 * If we have a previous abort, see whether 593 * this one is within the time limit. 594 */ 595 if (sc->sc_abortcount && 596 time.tv_sec >= sc->sc_starttime + ABT_WINDOW) 597 sc->sc_abortcount = 0; 598 /* 599 * If we see an abort after "idle" time, count it; 600 * record when the first abort escape arrived. 601 */ 602 if (time.tv_sec >= sc->sc_lasttime + ABT_IDLE) { 603 if (++sc->sc_abortcount == 1) 604 sc->sc_starttime = time.tv_sec; 605 if (sc->sc_abortcount >= ABT_COUNT) { 606 slclose(tp); 607 return; 608 } 609 } 610 } else 611 sc->sc_abortcount = 0; 612 sc->sc_lasttime = time.tv_sec; 613 } 614 615 switch (c) { 616 617 case TRANS_FRAME_ESCAPE: 618 if (sc->sc_escape) 619 c = FRAME_ESCAPE; 620 break; 621 622 case TRANS_FRAME_END: 623 if (sc->sc_escape) 624 c = FRAME_END; 625 break; 626 627 case FRAME_ESCAPE: 628 sc->sc_escape = 1; 629 return; 630 631 case FRAME_END: 632 if(sc->sc_flags & SC_ERROR) { 633 sc->sc_flags &= ~SC_ERROR; 634 goto newpack; 635 } 636 len = sc->sc_mp - sc->sc_pktstart; 637 if (len < 3) 638 /* less than min length packet - ignore */ 639 goto newpack; 640 641 m = sl_btom(sc, len); 642 if (m == NULL) 643 goto error; 644 645 IF_ENQUEUE(&sc->sc_inq, m); 646#ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 647 softintr_schedule(sc->sc_si); 648#else 649 { 650 int s = splimp(); 651 schednetisr(NETISR_SLIP); 652 splx(s); 653 } 654#endif 655 goto newpack; 656 } 657 if (sc->sc_mp < sc->sc_ep) { 658 *sc->sc_mp++ = c; 659 sc->sc_escape = 0; 660 return; 661 } 662 663 /* can't put lower; would miss an extra frame */ 664 sc->sc_flags |= SC_ERROR; 665 666error: 667 sc->sc_if.if_ierrors++; 668newpack: 669 sc->sc_mp = sc->sc_pktstart = (u_char *) sc->sc_mbuf->m_ext.ext_buf + 670 BUFOFFSET; 671 sc->sc_escape = 0; 672} 673 674#ifndef __HAVE_GENERIC_SOFT_INTERRUPTS 675void 676slnetisr(void) 677{ 678 struct sl_softc *sc; 679 int i; 680 681 for (i = 0; i < NSL; i++) { 682 sc = &sl_softc[i]; 683 if (sc->sc_ttyp == NULL) 684 continue; 685 slintr(sc); 686 } 687} 688#endif 689 690void 691slintr(void *arg) 692{ 693 struct sl_softc *sc = arg; 694 struct tty *tp = sc->sc_ttyp; 695 struct mbuf *m; 696 int s, len; 697 u_char *pktstart, c; 698#if NBPFILTER > 0 699 u_char chdr[CHDR_LEN]; 700#endif 701 702 KASSERT(tp != NULL); 703 704 /* 705 * Output processing loop. 706 */ 707 for (;;) { 708 struct ip *ip; 709 struct mbuf *m2; 710#if NBPFILTER > 0 711 struct mbuf *bpf_m; 712#endif 713 714 /* 715 * Do not remove the packet from the queue if it 716 * doesn't look like it will fit into the current 717 * serial output queue. With a packet full of 718 * escapes, this could be as bad as MTU*2+2. 719 */ 720 s = spltty(); 721 if (tp->t_outq.c_cn - tp->t_outq.c_cc < 722 2*sc->sc_if.if_mtu+2) { 723 splx(s); 724 break; 725 } 726 splx(s); 727 728 /* 729 * Get a packet and send it to the interface. 730 */ 731 s = splnet(); 732 IF_DEQUEUE(&sc->sc_fastq, m); 733 if (m) 734 sc->sc_if.if_omcasts++; /* XXX */ 735 else 736 IFQ_DEQUEUE(&sc->sc_if.if_snd, m); 737 splx(s); 738 739 if (m == NULL) 740 break; 741 742 /* 743 * We do the header compression here rather than in 744 * sloutput() because the packets will be out of order 745 * if we are using TOS queueing, and the connection 746 * ID compression will get munged when this happens. 747 */ 748#if NBPFILTER > 0 749 if (sc->sc_if.if_bpf) { 750 /* 751 * We need to save the TCP/IP header before 752 * it's compressed. To avoid complicated 753 * code, we just make a deep copy of the 754 * entire packet (since this is a serial 755 * line, packets should be short and/or the 756 * copy should be negligible cost compared 757 * to the packet transmission time). 758 */ 759 bpf_m = m_dup(m, 0, M_COPYALL, M_DONTWAIT); 760 } else 761 bpf_m = NULL; 762#endif 763 if ((ip = mtod(m, struct ip *))->ip_p == IPPROTO_TCP) { 764 if (sc->sc_if.if_flags & SC_COMPRESS) 765 *mtod(m, u_char *) |= 766 sl_compress_tcp(m, ip, 767 &sc->sc_comp, 1); 768 } 769#if NBPFILTER > 0 770 if (sc->sc_if.if_bpf && bpf_m != NULL) { 771 /* 772 * Put the SLIP pseudo-"link header" in 773 * place. The compressed header is now 774 * at the beginning of the mbuf. 775 */ 776 struct mbuf n; 777 u_char *hp; 778 779 n.m_next = bpf_m; 780 n.m_data = n.m_dat; 781 n.m_len = SLIP_HDRLEN; 782 783 hp = mtod(&n, u_char *); 784 785 hp[SLX_DIR] = SLIPDIR_OUT; 786 memcpy(&hp[SLX_CHDR], mtod(m, caddr_t), 787 CHDR_LEN); 788 789 s = splnet(); 790 bpf_mtap(sc->sc_if.if_bpf, &n); 791 splx(s); 792 m_freem(bpf_m); 793 } 794#endif 795 sc->sc_if.if_lastchange = time; 796 797 s = spltty(); 798 799 /* 800 * The extra FRAME_END will start up a new packet, 801 * and thus will flush any accumulated garbage. We 802 * do this whenever the line may have been idle for 803 * some time. 804 */ 805 if (tp->t_outq.c_cc == 0) { 806 sc->sc_if.if_obytes++; 807 (void) putc(FRAME_END, &tp->t_outq); 808 } 809 810 while (m) { 811 u_char *bp, *cp, *ep; 812 813 bp = cp = mtod(m, u_char *); 814 ep = cp + m->m_len; 815 while (cp < ep) { 816 /* 817 * Find out how many bytes in the 818 * string we can handle without 819 * doing something special. 820 */ 821 while (cp < ep) { 822 switch (*cp++) { 823 case FRAME_ESCAPE: 824 case FRAME_END: 825 cp--; 826 goto out; 827 } 828 } 829 out: 830 if (cp > bp) { 831 /* 832 * Put N characters at once 833 * into the tty output queue. 834 */ 835 if (b_to_q(bp, cp - bp, 836 &tp->t_outq)) 837 break; 838 sc->sc_if.if_obytes += cp - bp; 839 } 840 /* 841 * If there are characters left in 842 * the mbuf, the first one must be 843 * special.. Put it out in a different 844 * form. 845 */ 846 if (cp < ep) { 847 if (putc(FRAME_ESCAPE, 848 &tp->t_outq)) 849 break; 850 if (putc(*cp++ == FRAME_ESCAPE ? 851 TRANS_FRAME_ESCAPE : 852 TRANS_FRAME_END, 853 &tp->t_outq)) { 854 (void) 855 unputc(&tp->t_outq); 856 break; 857 } 858 sc->sc_if.if_obytes += 2; 859 } 860 } 861 MFREE(m, m2); 862 m = m2; 863 } 864 865 if (putc(FRAME_END, &tp->t_outq)) { 866 /* 867 * Not enough room. Remove a char to make 868 * room and end the packet normally. If 869 * you get many collisions (more than one 870 * or two a day), you probably do not have 871 * enough clists and you should increase 872 * "nclist" in param.c 873 */ 874 (void) unputc(&tp->t_outq); 875 (void) putc(FRAME_END, &tp->t_outq); 876 sc->sc_if.if_collisions++; 877 } else { 878 sc->sc_if.if_obytes++; 879 sc->sc_if.if_opackets++; 880 } 881 882 /* 883 * We now have characters in the output queue, 884 * kick the serial port. 885 */ 886 (*tp->t_oproc)(tp); 887 splx(s); 888 } 889 890 /* 891 * Input processing loop. 892 */ 893 for (;;) { 894 s = spltty(); 895 IF_DEQUEUE(&sc->sc_inq, m); 896 splx(s); 897 if (m == NULL) 898 break; 899 pktstart = mtod(m, u_char *); 900 len = m->m_pkthdr.len; 901#if NBPFILTER > 0 902 if (sc->sc_if.if_bpf) { 903 /* 904 * Save the compressed header, so we 905 * can tack it on later. Note that we 906 * will end up copying garbage in some 907 * cases but this is okay. We remember 908 * where the buffer started so we can 909 * compute the new header length. 910 */ 911 memcpy(chdr, pktstart, CHDR_LEN); 912 } 913#endif /* NBPFILTER > 0 */ 914 if ((c = (*pktstart & 0xf0)) != (IPVERSION << 4)) { 915 if (c & 0x80) 916 c = TYPE_COMPRESSED_TCP; 917 else if (c == TYPE_UNCOMPRESSED_TCP) 918 *pktstart &= 0x4f; /* XXX */ 919 /* 920 * We've got something that's not an IP 921 * packet. If compression is enabled, 922 * try to decompress it. Otherwise, if 923 * `auto-enable' compression is on and 924 * it's a reasonable packet, decompress 925 * it and then enable compression. 926 * Otherwise, drop it. 927 */ 928 if (sc->sc_if.if_flags & SC_COMPRESS) { 929 len = sl_uncompress_tcp(&pktstart, len, 930 (u_int)c, &sc->sc_comp); 931 if (len <= 0) { 932 m_freem(m); 933 continue; 934 } 935 } else if ((sc->sc_if.if_flags & SC_AUTOCOMP) && 936 c == TYPE_UNCOMPRESSED_TCP && len >= 40) { 937 len = sl_uncompress_tcp(&pktstart, len, 938 (u_int)c, &sc->sc_comp); 939 if (len <= 0) { 940 m_freem(m); 941 continue; 942 } 943 sc->sc_if.if_flags |= SC_COMPRESS; 944 } else { 945 m_freem(m); 946 continue; 947 } 948 } 949 m->m_data = (caddr_t) pktstart; 950 m->m_pkthdr.len = m->m_len = len; 951#if NBPFILTER > 0 952 if (sc->sc_if.if_bpf) { 953 /* 954 * Put the SLIP pseudo-"link header" in place. 955 * Note this M_PREPEND() should bever fail, 956 * since we know we always have enough space 957 * in the input buffer. 958 */ 959 u_char *hp; 960 961 M_PREPEND(m, SLIP_HDRLEN, M_DONTWAIT); 962 if (m == NULL) 963 continue; 964 965 hp = mtod(m, u_char *); 966 hp[SLX_DIR] = SLIPDIR_IN; 967 memcpy(&hp[SLX_CHDR], chdr, CHDR_LEN); 968 969 s = splnet(); 970 bpf_mtap(sc->sc_if.if_bpf, m); 971 splx(s); 972 973 m_adj(m, SLIP_HDRLEN); 974 } 975#endif /* NBPFILTER > 0 */ 976 /* 977 * If the packet will fit into a single 978 * header mbuf, copy it into one, to save 979 * memory. 980 */ 981 if (m->m_pkthdr.len < MHLEN) { 982 struct mbuf *n; 983 984 MGETHDR(n, M_DONTWAIT, MT_DATA); 985 M_COPY_PKTHDR(n, m); 986 memcpy(mtod(n, caddr_t), mtod(m, caddr_t), 987 m->m_pkthdr.len); 988 n->m_len = m->m_len; 989 m_freem(m); 990 m = n; 991 } 992 993 sc->sc_if.if_ipackets++; 994 sc->sc_if.if_lastchange = time; 995 996 s = splimp(); 997 if (IF_QFULL(&ipintrq)) { 998 IF_DROP(&ipintrq); 999 sc->sc_if.if_ierrors++; 1000 sc->sc_if.if_iqdrops++; 1001 m_freem(m); 1002 } else { 1003 IF_ENQUEUE(&ipintrq, m); 1004 schednetisr(NETISR_IP); 1005 } 1006 splx(s); 1007 } 1008} 1009 1010/* 1011 * Process an ioctl request. 1012 */ 1013int 1014slioctl(ifp, cmd, data) 1015 struct ifnet *ifp; 1016 u_long cmd; 1017 caddr_t data; 1018{ 1019 struct ifaddr *ifa = (struct ifaddr *)data; 1020 struct ifreq *ifr = (struct ifreq *)data; 1021 int s = splnet(), error = 0; 1022 struct sl_softc *sc = ifp->if_softc; 1023 1024 switch (cmd) { 1025 1026 case SIOCSIFADDR: 1027 if (ifa->ifa_addr->sa_family == AF_INET) 1028 ifp->if_flags |= IFF_UP; 1029 else 1030 error = EAFNOSUPPORT; 1031 break; 1032 1033 case SIOCSIFDSTADDR: 1034 if (ifa->ifa_addr->sa_family != AF_INET) 1035 error = EAFNOSUPPORT; 1036 break; 1037 1038 case SIOCSIFMTU: 1039 if ((ifr->ifr_mtu < 3) || (ifr->ifr_mtu > SLMAX)) { 1040 error = EINVAL; 1041 break; 1042 } 1043 sc->sc_if.if_mtu = ifr->ifr_mtu; 1044 break; 1045 1046 case SIOCGIFMTU: 1047 ifr->ifr_mtu = sc->sc_if.if_mtu; 1048 break; 1049 1050 case SIOCADDMULTI: 1051 case SIOCDELMULTI: 1052 if (ifr == 0) { 1053 error = EAFNOSUPPORT; /* XXX */ 1054 break; 1055 } 1056 switch (ifr->ifr_addr.sa_family) { 1057 1058#ifdef INET 1059 case AF_INET: 1060 break; 1061#endif 1062 1063 default: 1064 error = EAFNOSUPPORT; 1065 break; 1066 } 1067 break; 1068 1069 default: 1070 error = EINVAL; 1071 } 1072 splx(s); 1073 return (error); 1074} 1075#endif 1076