if_sl.c revision 1.107
1/* $NetBSD: if_sl.c,v 1.107 2007/09/01 04:32:50 dyoung 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 1.107 2007/09/01 04:32:50 dyoung 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#if __NetBSD__ 81#include <sys/systm.h> 82#include <sys/kauth.h> 83#endif 84 85#include <machine/cpu.h> 86#include <machine/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 int s; 307 308 if ((error = kauth_authorize_generic(l->l_cred, KAUTH_GENERIC_ISSUSER, 309 NULL)) != 0) 310 return error; 311 312 if (tp->t_linesw == &slip_disc) 313 return 0; 314 315 LIST_FOREACH(sc, &sl_softc_list, sc_iflist) 316 if (sc->sc_ttyp == NULL) { 317 sc->sc_si = softintr_establish(IPL_SOFTNET, 318 slintr, sc); 319 if (sc->sc_si == NULL) 320 return ENOMEM; 321 if (slinit(sc) == 0) { 322 softintr_disestablish(sc->sc_si); 323 return ENOBUFS; 324 } 325 tp->t_sc = (void *)sc; 326 sc->sc_ttyp = tp; 327 sc->sc_if.if_baudrate = tp->t_ospeed; 328 s = spltty(); 329 tp->t_state |= TS_ISOPEN | TS_XCLUDE; 330 splx(s); 331 ttyflush(tp, FREAD | FWRITE); 332#ifdef __NetBSD__ 333 /* 334 * make sure tty output queue is large enough 335 * to hold a full-sized packet (including frame 336 * end, and a possible extra frame end). full-sized 337 * packet occupies a max of 2*SLMAX bytes (because 338 * of possible escapes), and add two on for frame 339 * ends. 340 */ 341 s = spltty(); 342 if (tp->t_outq.c_cn < 2 * SLMAX + 2) { 343 sc->sc_oldbufsize = tp->t_outq.c_cn; 344 sc->sc_oldbufquot = tp->t_outq.c_cq != 0; 345 346 clfree(&tp->t_outq); 347 error = clalloc(&tp->t_outq, 2 * SLMAX + 2, 0); 348 if (error) { 349 splx(s); 350 softintr_disestablish(sc->sc_si); 351 /* 352 * clalloc() might return -1 which 353 * is no good, so we need to return 354 * something else. 355 */ 356 return ENOMEM; /* XXX ?! */ 357 } 358 } else 359 sc->sc_oldbufsize = sc->sc_oldbufquot = 0; 360 splx(s); 361#endif /* __NetBSD__ */ 362 return 0; 363 } 364 return ENXIO; 365} 366 367/* 368 * Line specific close routine. 369 * Detach the tty from the sl unit. 370 */ 371static int 372slclose(struct tty *tp, int flag) 373{ 374 struct sl_softc *sc; 375 int s; 376 377 ttywflush(tp); 378 sc = tp->t_sc; 379 380 if (sc != NULL) { 381 softintr_disestablish(sc->sc_si); 382 s = splnet(); 383 if_down(&sc->sc_if); 384 IF_PURGE(&sc->sc_fastq); 385 splx(s); 386 387 s = spltty(); 388 ttyldisc_release(tp->t_linesw); 389 tp->t_linesw = ttyldisc_default(); 390 tp->t_state = 0; 391 392 sc->sc_ttyp = NULL; 393 tp->t_sc = NULL; 394 395 m_freem(sc->sc_mbuf); 396 sc->sc_mbuf = NULL; 397 sc->sc_ep = sc->sc_mp = sc->sc_pktstart = NULL; 398 IF_PURGE(&sc->sc_inq); 399 400 /* 401 * If necessary, install a new outq buffer of the 402 * appropriate size. 403 */ 404 if (sc->sc_oldbufsize != 0) { 405 clfree(&tp->t_outq); 406 clalloc(&tp->t_outq, sc->sc_oldbufsize, 407 sc->sc_oldbufquot); 408 } 409 splx(s); 410 } 411 412 return 0; 413} 414 415/* 416 * Line specific (tty) ioctl routine. 417 * Provide a way to get the sl unit number. 418 */ 419/* ARGSUSED */ 420static int 421sltioctl(struct tty *tp, u_long cmd, void *data, int flag, 422 struct lwp *l) 423{ 424 struct sl_softc *sc = (struct sl_softc *)tp->t_sc; 425 426 switch (cmd) { 427 case SLIOCGUNIT: 428 *(int *)data = sc->sc_unit; /* XXX */ 429 break; 430 431 default: 432 return EPASSTHROUGH; 433 } 434 return 0; 435} 436 437/* 438 * Queue a packet. Start transmission if not active. 439 * Compression happens in slintr(); if we do it here, IP TOS 440 * will cause us to not compress "background" packets, because 441 * ordering gets trashed. It can be done for all packets in slintr(). 442 */ 443static int 444sloutput(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst, 445 struct rtentry *rtp) 446{ 447 struct sl_softc *sc = ifp->if_softc; 448 struct ip *ip; 449 struct ifqueue *ifq = NULL; 450 int s, error; 451 ALTQ_DECL(struct altq_pktattr pktattr;) 452 453 IFQ_CLASSIFY(&ifp->if_snd, m, dst->sa_family, &pktattr); 454 455 /* 456 * `Cannot happen' (see slioctl). Someday we will extend 457 * the line protocol to support other address families. 458 */ 459 if (dst->sa_family != AF_INET) { 460 printf("%s: af%d not supported\n", sc->sc_if.if_xname, 461 dst->sa_family); 462 m_freem(m); 463 sc->sc_if.if_noproto++; 464 return EAFNOSUPPORT; 465 } 466 467 if (sc->sc_ttyp == NULL) { 468 m_freem(m); 469 return ENETDOWN; /* sort of */ 470 } 471 if ((sc->sc_ttyp->t_state & TS_CARR_ON) == 0 && 472 (sc->sc_ttyp->t_cflag & CLOCAL) == 0) { 473 m_freem(m); 474 printf("%s: no carrier and not local\n", sc->sc_if.if_xname); 475 return EHOSTUNREACH; 476 } 477 ip = mtod(m, struct ip *); 478#ifdef INET 479 if (sc->sc_if.if_flags & SC_NOICMP && ip->ip_p == IPPROTO_ICMP) { 480 m_freem(m); 481 return ENETRESET; /* XXX ? */ 482 } 483#endif 484 485 s = spltty(); 486 if (sc->sc_oqlen && sc->sc_ttyp->t_outq.c_cc == sc->sc_oqlen) { 487 struct bintime bt; 488 489 /* if output's been stalled for too long, and restart */ 490 getbinuptime(&bt); 491 bintime_sub(&bt, &sc->sc_lastpacket); 492 if (bt.sec > 0) { 493 sc->sc_otimeout++; 494 slstart(sc->sc_ttyp); 495 } 496 } 497 splx(s); 498 499 s = splnet(); 500#ifdef INET 501 if ((ip->ip_tos & IPTOS_LOWDELAY) != 0) 502 ifq = &sc->sc_fastq; 503#endif 504 if ((error = ifq_enqueue2(ifp, ifq, m ALTQ_COMMA 505 ALTQ_DECL(&pktattr))) != 0) { 506 splx(s); 507 return error; 508 } 509 getbinuptime(&sc->sc_lastpacket); 510 splx(s); 511 512 s = spltty(); 513 if ((sc->sc_oqlen = sc->sc_ttyp->t_outq.c_cc) == 0) 514 slstart(sc->sc_ttyp); 515 splx(s); 516 517 return 0; 518} 519 520/* 521 * Start output on interface. Get another datagram 522 * to send from the interface queue and map it to 523 * the interface before starting output. 524 */ 525static int 526slstart(struct tty *tp) 527{ 528 struct sl_softc *sc = tp->t_sc; 529 530 /* 531 * If there is more in the output queue, just send it now. 532 * We are being called in lieu of ttstart and must do what 533 * it would. 534 */ 535 if (tp->t_outq.c_cc != 0) { 536 (*tp->t_oproc)(tp); 537 if (tp->t_outq.c_cc > SLIP_HIWAT) 538 return 0; 539 } 540 541 /* 542 * This happens briefly when the line shuts down. 543 */ 544 if (sc == NULL) 545 return 0; 546 softintr_schedule(sc->sc_si); 547 return 0; 548} 549 550/* 551 * Copy data buffer to mbuf chain; add ifnet pointer. 552 */ 553static struct mbuf * 554sl_btom(struct sl_softc *sc, int len) 555{ 556 struct mbuf *m; 557 558 /* 559 * Allocate a new input buffer and swap. 560 */ 561 m = sc->sc_mbuf; 562 MGETHDR(sc->sc_mbuf, M_DONTWAIT, MT_DATA); 563 if (sc->sc_mbuf == NULL) { 564 sc->sc_mbuf = m; 565 return NULL; 566 } 567 MCLGET(sc->sc_mbuf, M_DONTWAIT); 568 if ((sc->sc_mbuf->m_flags & M_EXT) == 0) { 569 m_freem(sc->sc_mbuf); 570 sc->sc_mbuf = m; 571 return NULL; 572 } 573 sc->sc_ep = (u_char *)sc->sc_mbuf->m_ext.ext_buf + 574 sc->sc_mbuf->m_ext.ext_size; 575 576 m->m_data = sc->sc_pktstart; 577 578 m->m_pkthdr.len = m->m_len = len; 579 m->m_pkthdr.rcvif = &sc->sc_if; 580 return m; 581} 582 583/* 584 * tty interface receiver interrupt. 585 */ 586static int 587slinput(int c, struct tty *tp) 588{ 589 struct sl_softc *sc; 590 struct mbuf *m; 591 int len; 592 593 tk_nin++; 594 sc = (struct sl_softc *)tp->t_sc; 595 if (sc == NULL) 596 return 0; 597 if ((c & TTY_ERRORMASK) || ((tp->t_state & TS_CARR_ON) == 0 && 598 (tp->t_cflag & CLOCAL) == 0)) { 599 sc->sc_flags |= SC_ERROR; 600 return 0; 601 } 602 c &= TTY_CHARMASK; 603 604 ++sc->sc_if.if_ibytes; 605 606 if (sc->sc_if.if_flags & IFF_DEBUG) { 607 if (c == ABT_ESC) { 608 /* 609 * If we have a previous abort, see whether 610 * this one is within the time limit. 611 */ 612 if (sc->sc_abortcount && 613 time_second >= sc->sc_starttime + ABT_WINDOW) 614 sc->sc_abortcount = 0; 615 /* 616 * If we see an abort after "idle" time, count it; 617 * record when the first abort escape arrived. 618 */ 619 if (time_second >= sc->sc_lasttime + ABT_IDLE) { 620 if (++sc->sc_abortcount == 1) 621 sc->sc_starttime = time_second; 622 if (sc->sc_abortcount >= ABT_COUNT) { 623 slclose(tp, 0); 624 return 0; 625 } 626 } 627 } else 628 sc->sc_abortcount = 0; 629 sc->sc_lasttime = time_second; 630 } 631 632 switch (c) { 633 634 case TRANS_FRAME_ESCAPE: 635 if (sc->sc_escape) 636 c = FRAME_ESCAPE; 637 break; 638 639 case TRANS_FRAME_END: 640 if (sc->sc_escape) 641 c = FRAME_END; 642 break; 643 644 case FRAME_ESCAPE: 645 sc->sc_escape = 1; 646 return 0; 647 648 case FRAME_END: 649 if (sc->sc_flags & SC_ERROR) { 650 sc->sc_flags &= ~SC_ERROR; 651 goto newpack; 652 } 653 len = sc->sc_mp - sc->sc_pktstart; 654 if (len < 3) 655 /* less than min length packet - ignore */ 656 goto newpack; 657 658 m = sl_btom(sc, len); 659 if (m == NULL) 660 goto error; 661 662 IF_ENQUEUE(&sc->sc_inq, m); 663 softintr_schedule(sc->sc_si); 664 goto newpack; 665 } 666 if (sc->sc_mp < sc->sc_ep) { 667 *sc->sc_mp++ = c; 668 sc->sc_escape = 0; 669 return 0; 670 } 671 672 /* can't put lower; would miss an extra frame */ 673 sc->sc_flags |= SC_ERROR; 674 675error: 676 sc->sc_if.if_ierrors++; 677newpack: 678 sc->sc_mp = sc->sc_pktstart = (u_char *)sc->sc_mbuf->m_ext.ext_buf + 679 BUFOFFSET; 680 sc->sc_escape = 0; 681 682 return 0; 683} 684 685static void 686slintr(void *arg) 687{ 688 struct sl_softc *sc = arg; 689 struct tty *tp = sc->sc_ttyp; 690 struct mbuf *m; 691 int s, len; 692 u_char *pktstart; 693#ifdef INET 694 u_char c; 695#endif 696#if NBPFILTER > 0 697 u_char chdr[CHDR_LEN]; 698#endif 699 700 KASSERT(tp != NULL); 701 702 /* 703 * Output processing loop. 704 */ 705 for (;;) { 706#ifdef INET 707 struct ip *ip; 708#endif 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#ifdef INET 764 if ((ip = mtod(m, struct ip *))->ip_p == IPPROTO_TCP) { 765 if (sc->sc_if.if_flags & SC_COMPRESS) 766 *mtod(m, u_char *) |= 767 sl_compress_tcp(m, ip, &sc->sc_comp, 1); 768 } 769#endif 770#if NBPFILTER > 0 771 if (sc->sc_if.if_bpf && bpf_m != NULL) 772 bpf_mtap_sl_out(sc->sc_if.if_bpf, mtod(m, u_char *), 773 bpf_m); 774#endif 775 getbinuptime(&sc->sc_lastpacket); 776 777 s = spltty(); 778 779 /* 780 * The extra FRAME_END will start up a new packet, 781 * and thus will flush any accumulated garbage. We 782 * do this whenever the line may have been idle for 783 * some time. 784 */ 785 if (tp->t_outq.c_cc == 0) { 786 sc->sc_if.if_obytes++; 787 (void)putc(FRAME_END, &tp->t_outq); 788 } 789 790 while (m) { 791 u_char *bp, *cp, *ep; 792 793 bp = cp = mtod(m, u_char *); 794 ep = cp + m->m_len; 795 while (cp < ep) { 796 /* 797 * Find out how many bytes in the 798 * string we can handle without 799 * doing something special. 800 */ 801 while (cp < ep) { 802 switch (*cp++) { 803 case FRAME_ESCAPE: 804 case FRAME_END: 805 cp--; 806 goto out; 807 } 808 } 809 out: 810 if (cp > bp) { 811 /* 812 * Put N characters at once 813 * into the tty output queue. 814 */ 815 if (b_to_q(bp, cp - bp, &tp->t_outq)) 816 break; 817 sc->sc_if.if_obytes += cp - bp; 818 } 819 /* 820 * If there are characters left in 821 * the mbuf, the first one must be 822 * special.. Put it out in a different 823 * form. 824 */ 825 if (cp < ep) { 826 if (putc(FRAME_ESCAPE, &tp->t_outq)) 827 break; 828 if (putc(*cp++ == FRAME_ESCAPE ? 829 TRANS_FRAME_ESCAPE : 830 TRANS_FRAME_END, 831 &tp->t_outq)) { 832 (void)unputc(&tp->t_outq); 833 break; 834 } 835 sc->sc_if.if_obytes += 2; 836 } 837 bp = cp; 838 } 839 MFREE(m, m2); 840 m = m2; 841 } 842 843 if (putc(FRAME_END, &tp->t_outq)) { 844 /* 845 * Not enough room. Remove a char to make 846 * room and end the packet normally. If 847 * you get many collisions (more than one 848 * or two a day), you probably do not have 849 * enough clists and you should increase 850 * "nclist" in param.c 851 */ 852 (void)unputc(&tp->t_outq); 853 (void)putc(FRAME_END, &tp->t_outq); 854 sc->sc_if.if_collisions++; 855 } else { 856 sc->sc_if.if_obytes++; 857 sc->sc_if.if_opackets++; 858 } 859 860 /* 861 * We now have characters in the output queue, 862 * kick the serial port. 863 */ 864 (*tp->t_oproc)(tp); 865 splx(s); 866 } 867 868 /* 869 * Input processing loop. 870 */ 871 for (;;) { 872 s = spltty(); 873 IF_DEQUEUE(&sc->sc_inq, m); 874 splx(s); 875 if (m == NULL) 876 break; 877 pktstart = mtod(m, u_char *); 878 len = m->m_pkthdr.len; 879#if NBPFILTER > 0 880 if (sc->sc_if.if_bpf) { 881 /* 882 * Save the compressed header, so we 883 * can tack it on later. Note that we 884 * will end up copying garbage in some 885 * cases but this is okay. We remember 886 * where the buffer started so we can 887 * compute the new header length. 888 */ 889 memcpy(chdr, pktstart, CHDR_LEN); 890 } 891#endif /* NBPFILTER > 0 */ 892#ifdef INET 893 if ((c = (*pktstart & 0xf0)) != (IPVERSION << 4)) { 894 if (c & 0x80) 895 c = TYPE_COMPRESSED_TCP; 896 else if (c == TYPE_UNCOMPRESSED_TCP) 897 *pktstart &= 0x4f; /* XXX */ 898 /* 899 * We've got something that's not an IP 900 * packet. If compression is enabled, 901 * try to decompress it. Otherwise, if 902 * `auto-enable' compression is on and 903 * it's a reasonable packet, decompress 904 * it and then enable compression. 905 * Otherwise, drop it. 906 */ 907 if (sc->sc_if.if_flags & SC_COMPRESS) { 908 len = sl_uncompress_tcp(&pktstart, len, 909 (u_int)c, &sc->sc_comp); 910 if (len <= 0) { 911 m_freem(m); 912 continue; 913 } 914 } else if ((sc->sc_if.if_flags & SC_AUTOCOMP) && 915 c == TYPE_UNCOMPRESSED_TCP && len >= 40) { 916 len = sl_uncompress_tcp(&pktstart, len, 917 (u_int)c, &sc->sc_comp); 918 if (len <= 0) { 919 m_freem(m); 920 continue; 921 } 922 sc->sc_if.if_flags |= SC_COMPRESS; 923 } else { 924 m_freem(m); 925 continue; 926 } 927 } 928#endif 929 m->m_data = (void *) pktstart; 930 m->m_pkthdr.len = m->m_len = len; 931#if NBPFILTER > 0 932 if (sc->sc_if.if_bpf) { 933 bpf_mtap_sl_in(sc->sc_if.if_bpf, chdr, &m); 934 if (m == NULL) 935 continue; 936 } 937#endif /* NBPFILTER > 0 */ 938 /* 939 * If the packet will fit into a single 940 * header mbuf, copy it into one, to save 941 * memory. 942 */ 943 if (m->m_pkthdr.len < MHLEN) { 944 struct mbuf *n; 945 int pktlen; 946 947 MGETHDR(n, M_DONTWAIT, MT_DATA); 948 pktlen = m->m_pkthdr.len; 949 M_MOVE_PKTHDR(n, m); 950 memcpy(mtod(n, void *), mtod(m, void *), pktlen); 951 n->m_len = m->m_len; 952 m_freem(m); 953 m = n; 954 } 955 956 sc->sc_if.if_ipackets++; 957 getbinuptime(&sc->sc_lastpacket); 958 959#ifdef INET 960 s = splnet(); 961 if (IF_QFULL(&ipintrq)) { 962 IF_DROP(&ipintrq); 963 sc->sc_if.if_ierrors++; 964 sc->sc_if.if_iqdrops++; 965 m_freem(m); 966 } else { 967 IF_ENQUEUE(&ipintrq, m); 968 schednetisr(NETISR_IP); 969 } 970 splx(s); 971#endif 972 } 973} 974 975/* 976 * Process an ioctl request. 977 */ 978static int 979slioctl(struct ifnet *ifp, u_long cmd, void *data) 980{ 981 struct ifaddr *ifa = (struct ifaddr *)data; 982 struct ifreq *ifr = (struct ifreq *)data; 983 int s = splnet(), error = 0; 984 struct sl_softc *sc = ifp->if_softc; 985 struct ppp_stats *psp; 986 struct ppp_comp_stats *pcp; 987 988 switch (cmd) { 989 990 case SIOCSIFADDR: 991 if (ifa->ifa_addr->sa_family == AF_INET) 992 ifp->if_flags |= IFF_UP; 993 else 994 error = EAFNOSUPPORT; 995 break; 996 997 case SIOCSIFDSTADDR: 998 if (ifa->ifa_addr->sa_family != AF_INET) 999 error = EAFNOSUPPORT; 1000 break; 1001 1002 case SIOCSIFMTU: 1003 if ((ifr->ifr_mtu < 3) || (ifr->ifr_mtu > SLMAX)) { 1004 error = EINVAL; 1005 break; 1006 } 1007 sc->sc_if.if_mtu = ifr->ifr_mtu; 1008 break; 1009 1010 case SIOCGIFMTU: 1011 ifr->ifr_mtu = sc->sc_if.if_mtu; 1012 break; 1013 1014 case SIOCADDMULTI: 1015 case SIOCDELMULTI: 1016 if (ifr == 0) { 1017 error = EAFNOSUPPORT; /* XXX */ 1018 break; 1019 } 1020 switch (ifreq_getaddr(cmd, ifr)->sa_family) { 1021 1022#ifdef INET 1023 case AF_INET: 1024 break; 1025#endif 1026 1027 default: 1028 error = EAFNOSUPPORT; 1029 break; 1030 } 1031 break; 1032 1033 case SIOCGPPPSTATS: 1034 psp = &((struct ifpppstatsreq *) data)->stats; 1035 (void)memset(psp, 0, sizeof(*psp)); 1036 psp->p.ppp_ibytes = sc->sc_if.if_ibytes; 1037 psp->p.ppp_ipackets = sc->sc_if.if_ipackets; 1038 psp->p.ppp_ierrors = sc->sc_if.if_ierrors; 1039 psp->p.ppp_obytes = sc->sc_if.if_obytes; 1040 psp->p.ppp_opackets = sc->sc_if.if_opackets; 1041 psp->p.ppp_oerrors = sc->sc_if.if_oerrors; 1042#ifdef INET 1043 psp->vj.vjs_packets = sc->sc_comp.sls_packets; 1044 psp->vj.vjs_compressed = sc->sc_comp.sls_compressed; 1045 psp->vj.vjs_searches = sc->sc_comp.sls_searches; 1046 psp->vj.vjs_misses = sc->sc_comp.sls_misses; 1047 psp->vj.vjs_uncompressedin = sc->sc_comp.sls_uncompressedin; 1048 psp->vj.vjs_compressedin = sc->sc_comp.sls_compressedin; 1049 psp->vj.vjs_errorin = sc->sc_comp.sls_errorin; 1050 psp->vj.vjs_tossed = sc->sc_comp.sls_tossed; 1051#endif 1052 break; 1053 1054 case SIOCGPPPCSTATS: 1055 pcp = &((struct ifpppcstatsreq *) data)->stats; 1056 (void)memset(pcp, 0, sizeof(*pcp)); 1057 break; 1058 1059 default: 1060 error = EINVAL; 1061 } 1062 splx(s); 1063 return error; 1064} 1065