if_sl.c revision 1.97
1/* $NetBSD: if_sl.c,v 1.97 2006/05/14 21:19:33 elad 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 1.97 2006/05/14 21:19:33 elad 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 */ 189 190#ifndef __HAVE_GENERIC_SOFT_INTERRUPTS 191void slnetisr(void); 192#endif 193static void slintr(void *); 194 195static int slinit(struct sl_softc *); 196static struct mbuf *sl_btom(struct sl_softc *, int); 197 198static int slclose(struct tty *, int); 199static int slinput(int, struct tty *); 200static int slioctl(struct ifnet *, u_long, caddr_t); 201static int slopen(dev_t, struct tty *); 202static int sloutput(struct ifnet *, struct mbuf *, struct sockaddr *, 203 struct rtentry *); 204static int slstart(struct tty *); 205static int sltioctl(struct tty *, u_long, caddr_t, int, struct lwp *); 206 207static struct linesw slip_disc = { 208 .l_name = "slip", 209 .l_open = slopen, 210 .l_close = slclose, 211 .l_read = ttyerrio, 212 .l_write = ttyerrio, 213 .l_ioctl = sltioctl, 214 .l_rint = slinput, 215 .l_start = slstart, 216 .l_modem = nullmodem, 217 .l_poll = ttyerrpoll 218}; 219 220void slattach(void); 221 222void 223slattach(void) 224{ 225 if (ttyldisc_attach(&slip_disc) != 0) 226 panic("slattach"); 227 LIST_INIT(&sl_softc_list); 228 if_clone_attach(&sl_cloner); 229} 230 231static int 232sl_clone_create(struct if_clone *ifc, int unit) 233{ 234 struct sl_softc *sc; 235 236 MALLOC(sc, struct sl_softc *, sizeof(*sc), M_DEVBUF, M_WAIT|M_ZERO); 237 sc->sc_unit = unit; 238 (void)snprintf(sc->sc_if.if_xname, sizeof(sc->sc_if.if_xname), 239 "%s%d", ifc->ifc_name, unit); 240 sc->sc_if.if_softc = sc; 241 sc->sc_if.if_mtu = SLMTU; 242 sc->sc_if.if_flags = IFF_POINTOPOINT | SC_AUTOCOMP | IFF_MULTICAST; 243 sc->sc_if.if_type = IFT_SLIP; 244 sc->sc_if.if_ioctl = slioctl; 245 sc->sc_if.if_output = sloutput; 246 sc->sc_if.if_dlt = DLT_SLIP; 247 sc->sc_fastq.ifq_maxlen = 32; 248 IFQ_SET_READY(&sc->sc_if.if_snd); 249 if_attach(&sc->sc_if); 250 if_alloc_sadl(&sc->sc_if); 251#if NBPFILTER > 0 252 bpfattach(&sc->sc_if, DLT_SLIP, SLIP_HDRLEN); 253#endif 254 LIST_INSERT_HEAD(&sl_softc_list, sc, sc_iflist); 255 return 0; 256} 257 258static int 259sl_clone_destroy(struct ifnet *ifp) 260{ 261 struct sl_softc *sc = (struct sl_softc *)ifp->if_softc; 262 263 if (sc->sc_ttyp != NULL) 264 return EBUSY; /* Not removing it */ 265 266 LIST_REMOVE(sc, sc_iflist); 267 268#if NBPFILTER > 0 269 bpfdetach(ifp); 270#endif 271 if_detach(ifp); 272 273 FREE(sc, M_DEVBUF); 274 return 0; 275} 276 277static int 278slinit(struct sl_softc *sc) 279{ 280 281 if (sc->sc_mbuf == NULL) { 282 sc->sc_mbuf = m_gethdr(M_WAIT, MT_DATA); 283 m_clget(sc->sc_mbuf, M_WAIT); 284 } 285 sc->sc_ep = (u_char *) sc->sc_mbuf->m_ext.ext_buf + 286 sc->sc_mbuf->m_ext.ext_size; 287 sc->sc_mp = sc->sc_pktstart = (u_char *) sc->sc_mbuf->m_ext.ext_buf + 288 BUFOFFSET; 289 290#ifdef INET 291 sl_compress_init(&sc->sc_comp); 292#endif 293 294 return (1); 295} 296 297/* 298 * Line specific open routine. 299 * Attach the given tty to the first available sl unit. 300 */ 301/* ARGSUSED */ 302static int 303slopen(dev_t dev, struct tty *tp) 304{ 305 struct proc *p = curproc; /* XXX */ 306 struct sl_softc *sc; 307 int error; 308 int s; 309 310 if ((error = kauth_authorize_generic(p->p_cred, KAUTH_GENERIC_ISSUSER, &p->p_acflag)) != 0) 311 return (error); 312 313 if (tp->t_linesw == &slip_disc) 314 return (0); 315 316 LIST_FOREACH(sc, &sl_softc_list, sc_iflist) 317 if (sc->sc_ttyp == NULL) { 318#ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 319 sc->sc_si = softintr_establish(IPL_SOFTNET, 320 slintr, sc); 321 if (sc->sc_si == NULL) 322 return (ENOMEM); 323#endif 324 if (slinit(sc) == 0) { 325#ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 326 softintr_disestablish(sc->sc_si); 327#endif 328 return (ENOBUFS); 329 } 330 tp->t_sc = (caddr_t)sc; 331 sc->sc_ttyp = tp; 332 sc->sc_if.if_baudrate = tp->t_ospeed; 333 s = spltty(); 334 tp->t_state |= TS_ISOPEN | TS_XCLUDE; 335 splx(s); 336 ttyflush(tp, FREAD | FWRITE); 337#ifdef __NetBSD__ 338 /* 339 * make sure tty output queue is large enough 340 * to hold a full-sized packet (including frame 341 * end, and a possible extra frame end). full-sized 342 * packet occupies a max of 2*SLMAX bytes (because 343 * of possible escapes), and add two on for frame 344 * ends. 345 */ 346 s = spltty(); 347 if (tp->t_outq.c_cn < 2*SLMAX+2) { 348 sc->sc_oldbufsize = tp->t_outq.c_cn; 349 sc->sc_oldbufquot = tp->t_outq.c_cq != 0; 350 351 clfree(&tp->t_outq); 352 error = clalloc(&tp->t_outq, 2*SLMAX+2, 0); 353 if (error) { 354 splx(s); 355#ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 356 softintr_disestablish(sc->sc_si); 357#endif 358 /* 359 * clalloc() might return -1 which 360 * is no good, so we need to return 361 * something else. 362 */ 363 return (ENOMEM); /* XXX ?! */ 364 } 365 } else 366 sc->sc_oldbufsize = sc->sc_oldbufquot = 0; 367 splx(s); 368#endif /* __NetBSD__ */ 369 return (0); 370 } 371 return (ENXIO); 372} 373 374/* 375 * Line specific close routine. 376 * Detach the tty from the sl unit. 377 */ 378static int 379slclose(struct tty *tp, int flag) 380{ 381 struct sl_softc *sc; 382 int s; 383 384 ttywflush(tp); 385 sc = tp->t_sc; 386 387 if (sc != NULL) { 388#ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 389 softintr_disestablish(sc->sc_si); 390#endif 391 s = splnet(); 392 if_down(&sc->sc_if); 393 IF_PURGE(&sc->sc_fastq); 394 splx(s); 395 396 s = spltty(); 397 ttyldisc_release(tp->t_linesw); 398 tp->t_linesw = ttyldisc_default(); 399 tp->t_state = 0; 400 401 sc->sc_ttyp = NULL; 402 tp->t_sc = NULL; 403 404 m_freem(sc->sc_mbuf); 405 sc->sc_mbuf = NULL; 406 sc->sc_ep = sc->sc_mp = sc->sc_pktstart = NULL; 407 IF_PURGE(&sc->sc_inq); 408 409 /* 410 * If necessary, install a new outq buffer of the 411 * appropriate size. 412 */ 413 if (sc->sc_oldbufsize != 0) { 414 clfree(&tp->t_outq); 415 clalloc(&tp->t_outq, sc->sc_oldbufsize, 416 sc->sc_oldbufquot); 417 } 418 splx(s); 419 } 420 421 return (0); 422} 423 424/* 425 * Line specific (tty) ioctl routine. 426 * Provide a way to get the sl unit number. 427 */ 428/* ARGSUSED */ 429static int 430sltioctl(struct tty *tp, u_long cmd, caddr_t data, int flag, struct lwp *l) 431{ 432 struct sl_softc *sc = (struct sl_softc *)tp->t_sc; 433 434 switch (cmd) { 435 case SLIOCGUNIT: 436 *(int *)data = sc->sc_unit; /* XXX */ 437 break; 438 439 default: 440 return (EPASSTHROUGH); 441 } 442 return (0); 443} 444 445/* 446 * Queue a packet. Start transmission if not active. 447 * Compression happens in slintr(); if we do it here, IP TOS 448 * will cause us to not compress "background" packets, because 449 * ordering gets trashed. It can be done for all packets in slintr(). 450 */ 451static int 452sloutput(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst, 453 struct rtentry *rtp) 454{ 455 struct sl_softc *sc = ifp->if_softc; 456 struct ip *ip; 457 struct ifqueue *ifq = NULL; 458 int s, error; 459 ALTQ_DECL(struct altq_pktattr pktattr;) 460 461 IFQ_CLASSIFY(&ifp->if_snd, m, dst->sa_family, &pktattr); 462 463 /* 464 * `Cannot happen' (see slioctl). Someday we will extend 465 * the line protocol to support other address families. 466 */ 467 if (dst->sa_family != AF_INET) { 468 printf("%s: af%d not supported\n", sc->sc_if.if_xname, 469 dst->sa_family); 470 m_freem(m); 471 sc->sc_if.if_noproto++; 472 return (EAFNOSUPPORT); 473 } 474 475 if (sc->sc_ttyp == NULL) { 476 m_freem(m); 477 return (ENETDOWN); /* sort of */ 478 } 479 if ((sc->sc_ttyp->t_state & TS_CARR_ON) == 0 && 480 (sc->sc_ttyp->t_cflag & CLOCAL) == 0) { 481 m_freem(m); 482 printf("%s: no carrier and not local\n", sc->sc_if.if_xname); 483 return (EHOSTUNREACH); 484 } 485 ip = mtod(m, struct ip *); 486#ifdef INET 487 if (sc->sc_if.if_flags & SC_NOICMP && ip->ip_p == IPPROTO_ICMP) { 488 m_freem(m); 489 return (ENETRESET); /* XXX ? */ 490 } 491#endif 492 493 s = spltty(); 494 if (sc->sc_oqlen && sc->sc_ttyp->t_outq.c_cc == sc->sc_oqlen) { 495 struct timeval tv; 496 497 /* if output's been stalled for too long, and restart */ 498 timersub(&time, &sc->sc_lastpacket, &tv); 499 if (tv.tv_sec > 0) { 500 sc->sc_otimeout++; 501 slstart(sc->sc_ttyp); 502 } 503 } 504 splx(s); 505 506 s = splnet(); 507#ifdef INET 508 if ((ip->ip_tos & IPTOS_LOWDELAY) != 0) 509 ifq = &sc->sc_fastq; 510#endif 511 if ((error = ifq_enqueue2(ifp, ifq, m ALTQ_COMMA 512 ALTQ_DECL(&pktattr))) != 0) { 513 splx(s); 514 return error; 515 } 516 sc->sc_lastpacket = time; 517 splx(s); 518 519 s = spltty(); 520 if ((sc->sc_oqlen = sc->sc_ttyp->t_outq.c_cc) == 0) 521 slstart(sc->sc_ttyp); 522 splx(s); 523 524 return (0); 525} 526 527/* 528 * Start output on interface. Get another datagram 529 * to send from the interface queue and map it to 530 * the interface before starting output. 531 */ 532static int 533slstart(struct tty *tp) 534{ 535 struct sl_softc *sc = tp->t_sc; 536 537 /* 538 * If there is more in the output queue, just send it now. 539 * We are being called in lieu of ttstart and must do what 540 * it would. 541 */ 542 if (tp->t_outq.c_cc != 0) { 543 (*tp->t_oproc)(tp); 544 if (tp->t_outq.c_cc > SLIP_HIWAT) 545 return (0); 546 } 547 548 /* 549 * This happens briefly when the line shuts down. 550 */ 551 if (sc == NULL) 552 return (0); 553#ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 554 softintr_schedule(sc->sc_si); 555#else 556 { 557 int s = splhigh(); 558 schednetisr(NETISR_SLIP); 559 splx(s); 560 } 561#endif 562 return (0); 563} 564 565/* 566 * Copy data buffer to mbuf chain; add ifnet pointer. 567 */ 568static struct mbuf * 569sl_btom(struct sl_softc *sc, int len) 570{ 571 struct mbuf *m; 572 573 /* 574 * Allocate a new input buffer and swap. 575 */ 576 m = sc->sc_mbuf; 577 MGETHDR(sc->sc_mbuf, M_DONTWAIT, MT_DATA); 578 if (sc->sc_mbuf == NULL) { 579 sc->sc_mbuf = m; 580 return (NULL); 581 } 582 MCLGET(sc->sc_mbuf, M_DONTWAIT); 583 if ((sc->sc_mbuf->m_flags & M_EXT) == 0) { 584 m_freem(sc->sc_mbuf); 585 sc->sc_mbuf = m; 586 return (NULL); 587 } 588 sc->sc_ep = (u_char *) sc->sc_mbuf->m_ext.ext_buf + 589 sc->sc_mbuf->m_ext.ext_size; 590 591 m->m_data = sc->sc_pktstart; 592 593 m->m_pkthdr.len = m->m_len = len; 594 m->m_pkthdr.rcvif = &sc->sc_if; 595 return (m); 596} 597 598/* 599 * tty interface receiver interrupt. 600 */ 601static int 602slinput(int c, struct tty *tp) 603{ 604 struct sl_softc *sc; 605 struct mbuf *m; 606 int len; 607 608 tk_nin++; 609 sc = (struct sl_softc *)tp->t_sc; 610 if (sc == NULL) 611 return (0); 612 if ((c & TTY_ERRORMASK) || ((tp->t_state & TS_CARR_ON) == 0 && 613 (tp->t_cflag & CLOCAL) == 0)) { 614 sc->sc_flags |= SC_ERROR; 615 return (0); 616 } 617 c &= TTY_CHARMASK; 618 619 ++sc->sc_if.if_ibytes; 620 621 if (sc->sc_if.if_flags & IFF_DEBUG) { 622 if (c == ABT_ESC) { 623 /* 624 * If we have a previous abort, see whether 625 * this one is within the time limit. 626 */ 627 if (sc->sc_abortcount && 628 time.tv_sec >= sc->sc_starttime + ABT_WINDOW) 629 sc->sc_abortcount = 0; 630 /* 631 * If we see an abort after "idle" time, count it; 632 * record when the first abort escape arrived. 633 */ 634 if (time.tv_sec >= sc->sc_lasttime + ABT_IDLE) { 635 if (++sc->sc_abortcount == 1) 636 sc->sc_starttime = time.tv_sec; 637 if (sc->sc_abortcount >= ABT_COUNT) { 638 slclose(tp, 0); 639 return (0); 640 } 641 } 642 } else 643 sc->sc_abortcount = 0; 644 sc->sc_lasttime = time.tv_sec; 645 } 646 647 switch (c) { 648 649 case TRANS_FRAME_ESCAPE: 650 if (sc->sc_escape) 651 c = FRAME_ESCAPE; 652 break; 653 654 case TRANS_FRAME_END: 655 if (sc->sc_escape) 656 c = FRAME_END; 657 break; 658 659 case FRAME_ESCAPE: 660 sc->sc_escape = 1; 661 return (0); 662 663 case FRAME_END: 664 if(sc->sc_flags & SC_ERROR) { 665 sc->sc_flags &= ~SC_ERROR; 666 goto newpack; 667 } 668 len = sc->sc_mp - sc->sc_pktstart; 669 if (len < 3) 670 /* less than min length packet - ignore */ 671 goto newpack; 672 673 m = sl_btom(sc, len); 674 if (m == NULL) 675 goto error; 676 677 IF_ENQUEUE(&sc->sc_inq, m); 678#ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 679 softintr_schedule(sc->sc_si); 680#else 681 { 682 int s = splhigh(); 683 schednetisr(NETISR_SLIP); 684 splx(s); 685 } 686#endif 687 goto newpack; 688 } 689 if (sc->sc_mp < sc->sc_ep) { 690 *sc->sc_mp++ = c; 691 sc->sc_escape = 0; 692 return (0); 693 } 694 695 /* can't put lower; would miss an extra frame */ 696 sc->sc_flags |= SC_ERROR; 697 698error: 699 sc->sc_if.if_ierrors++; 700newpack: 701 sc->sc_mp = sc->sc_pktstart = (u_char *) sc->sc_mbuf->m_ext.ext_buf + 702 BUFOFFSET; 703 sc->sc_escape = 0; 704 705 return (0); 706} 707 708#ifndef __HAVE_GENERIC_SOFT_INTERRUPTS 709void 710slnetisr(void) 711{ 712 struct sl_softc *sc; 713 714 LIST_FOREACH(sc, &sl_softc_list, sc_iflist) { 715 if (sc->sc_ttyp == NULL) 716 continue; 717 slintr(sc); 718 } 719} 720#endif 721 722static void 723slintr(void *arg) 724{ 725 struct sl_softc *sc = arg; 726 struct tty *tp = sc->sc_ttyp; 727 struct mbuf *m; 728 int s, len; 729 u_char *pktstart; 730#ifdef INET 731 u_char c; 732#endif 733#if NBPFILTER > 0 734 u_char chdr[CHDR_LEN]; 735#endif 736 737 KASSERT(tp != NULL); 738 739 /* 740 * Output processing loop. 741 */ 742 for (;;) { 743#ifdef INET 744 struct ip *ip; 745#endif 746 struct mbuf *m2; 747#if NBPFILTER > 0 748 struct mbuf *bpf_m; 749#endif 750 751 /* 752 * Do not remove the packet from the queue if it 753 * doesn't look like it will fit into the current 754 * serial output queue. With a packet full of 755 * escapes, this could be as bad as MTU*2+2. 756 */ 757 s = spltty(); 758 if (tp->t_outq.c_cn - tp->t_outq.c_cc < 759 2*sc->sc_if.if_mtu+2) { 760 splx(s); 761 break; 762 } 763 splx(s); 764 765 /* 766 * Get a packet and send it to the interface. 767 */ 768 s = splnet(); 769 IF_DEQUEUE(&sc->sc_fastq, m); 770 if (m) 771 sc->sc_if.if_omcasts++; /* XXX */ 772 else 773 IFQ_DEQUEUE(&sc->sc_if.if_snd, m); 774 splx(s); 775 776 if (m == NULL) 777 break; 778 779 /* 780 * We do the header compression here rather than in 781 * sloutput() because the packets will be out of order 782 * if we are using TOS queueing, and the connection 783 * ID compression will get munged when this happens. 784 */ 785#if NBPFILTER > 0 786 if (sc->sc_if.if_bpf) { 787 /* 788 * We need to save the TCP/IP header before 789 * it's compressed. To avoid complicated 790 * code, we just make a deep copy of the 791 * entire packet (since this is a serial 792 * line, packets should be short and/or the 793 * copy should be negligible cost compared 794 * to the packet transmission time). 795 */ 796 bpf_m = m_dup(m, 0, M_COPYALL, M_DONTWAIT); 797 } else 798 bpf_m = NULL; 799#endif 800#ifdef INET 801 if ((ip = mtod(m, struct ip *))->ip_p == IPPROTO_TCP) { 802 if (sc->sc_if.if_flags & SC_COMPRESS) 803 *mtod(m, u_char *) |= 804 sl_compress_tcp(m, ip, 805 &sc->sc_comp, 1); 806 } 807#endif 808#if NBPFILTER > 0 809 if (sc->sc_if.if_bpf && bpf_m != NULL) 810 bpf_mtap_sl_out(sc->sc_if.if_bpf, mtod(m, u_char *), 811 bpf_m); 812#endif 813 sc->sc_lastpacket = time; 814 815 s = spltty(); 816 817 /* 818 * The extra FRAME_END will start up a new packet, 819 * and thus will flush any accumulated garbage. We 820 * do this whenever the line may have been idle for 821 * some time. 822 */ 823 if (tp->t_outq.c_cc == 0) { 824 sc->sc_if.if_obytes++; 825 (void) putc(FRAME_END, &tp->t_outq); 826 } 827 828 while (m) { 829 u_char *bp, *cp, *ep; 830 831 bp = cp = mtod(m, u_char *); 832 ep = cp + m->m_len; 833 while (cp < ep) { 834 /* 835 * Find out how many bytes in the 836 * string we can handle without 837 * doing something special. 838 */ 839 while (cp < ep) { 840 switch (*cp++) { 841 case FRAME_ESCAPE: 842 case FRAME_END: 843 cp--; 844 goto out; 845 } 846 } 847 out: 848 if (cp > bp) { 849 /* 850 * Put N characters at once 851 * into the tty output queue. 852 */ 853 if (b_to_q(bp, cp - bp, 854 &tp->t_outq)) 855 break; 856 sc->sc_if.if_obytes += cp - bp; 857 } 858 /* 859 * If there are characters left in 860 * the mbuf, the first one must be 861 * special.. Put it out in a different 862 * form. 863 */ 864 if (cp < ep) { 865 if (putc(FRAME_ESCAPE, 866 &tp->t_outq)) 867 break; 868 if (putc(*cp++ == FRAME_ESCAPE ? 869 TRANS_FRAME_ESCAPE : 870 TRANS_FRAME_END, 871 &tp->t_outq)) { 872 (void) 873 unputc(&tp->t_outq); 874 break; 875 } 876 sc->sc_if.if_obytes += 2; 877 } 878 bp = cp; 879 } 880 MFREE(m, m2); 881 m = m2; 882 } 883 884 if (putc(FRAME_END, &tp->t_outq)) { 885 /* 886 * Not enough room. Remove a char to make 887 * room and end the packet normally. If 888 * you get many collisions (more than one 889 * or two a day), you probably do not have 890 * enough clists and you should increase 891 * "nclist" in param.c 892 */ 893 (void) unputc(&tp->t_outq); 894 (void) putc(FRAME_END, &tp->t_outq); 895 sc->sc_if.if_collisions++; 896 } else { 897 sc->sc_if.if_obytes++; 898 sc->sc_if.if_opackets++; 899 } 900 901 /* 902 * We now have characters in the output queue, 903 * kick the serial port. 904 */ 905 (*tp->t_oproc)(tp); 906 splx(s); 907 } 908 909 /* 910 * Input processing loop. 911 */ 912 for (;;) { 913 s = spltty(); 914 IF_DEQUEUE(&sc->sc_inq, m); 915 splx(s); 916 if (m == NULL) 917 break; 918 pktstart = mtod(m, u_char *); 919 len = m->m_pkthdr.len; 920#if NBPFILTER > 0 921 if (sc->sc_if.if_bpf) { 922 /* 923 * Save the compressed header, so we 924 * can tack it on later. Note that we 925 * will end up copying garbage in some 926 * cases but this is okay. We remember 927 * where the buffer started so we can 928 * compute the new header length. 929 */ 930 memcpy(chdr, pktstart, CHDR_LEN); 931 } 932#endif /* NBPFILTER > 0 */ 933#ifdef INET 934 if ((c = (*pktstart & 0xf0)) != (IPVERSION << 4)) { 935 if (c & 0x80) 936 c = TYPE_COMPRESSED_TCP; 937 else if (c == TYPE_UNCOMPRESSED_TCP) 938 *pktstart &= 0x4f; /* XXX */ 939 /* 940 * We've got something that's not an IP 941 * packet. If compression is enabled, 942 * try to decompress it. Otherwise, if 943 * `auto-enable' compression is on and 944 * it's a reasonable packet, decompress 945 * it and then enable compression. 946 * Otherwise, drop it. 947 */ 948 if (sc->sc_if.if_flags & SC_COMPRESS) { 949 len = sl_uncompress_tcp(&pktstart, len, 950 (u_int)c, &sc->sc_comp); 951 if (len <= 0) { 952 m_freem(m); 953 continue; 954 } 955 } else if ((sc->sc_if.if_flags & SC_AUTOCOMP) && 956 c == TYPE_UNCOMPRESSED_TCP && len >= 40) { 957 len = sl_uncompress_tcp(&pktstart, len, 958 (u_int)c, &sc->sc_comp); 959 if (len <= 0) { 960 m_freem(m); 961 continue; 962 } 963 sc->sc_if.if_flags |= SC_COMPRESS; 964 } else { 965 m_freem(m); 966 continue; 967 } 968 } 969#endif 970 m->m_data = (caddr_t) pktstart; 971 m->m_pkthdr.len = m->m_len = len; 972#if NBPFILTER > 0 973 if (sc->sc_if.if_bpf) { 974 bpf_mtap_sl_in(sc->sc_if.if_bpf, chdr, &m); 975 if (m == NULL) 976 continue; 977 } 978#endif /* NBPFILTER > 0 */ 979 /* 980 * If the packet will fit into a single 981 * header mbuf, copy it into one, to save 982 * memory. 983 */ 984 if (m->m_pkthdr.len < MHLEN) { 985 struct mbuf *n; 986 int pktlen; 987 988 MGETHDR(n, M_DONTWAIT, MT_DATA); 989 pktlen = m->m_pkthdr.len; 990 M_MOVE_PKTHDR(n, m); 991 memcpy(mtod(n, caddr_t), mtod(m, caddr_t), pktlen); 992 n->m_len = m->m_len; 993 m_freem(m); 994 m = n; 995 } 996 997 sc->sc_if.if_ipackets++; 998 sc->sc_lastpacket = time; 999 1000#ifdef INET 1001 s = splnet(); 1002 if (IF_QFULL(&ipintrq)) { 1003 IF_DROP(&ipintrq); 1004 sc->sc_if.if_ierrors++; 1005 sc->sc_if.if_iqdrops++; 1006 m_freem(m); 1007 } else { 1008 IF_ENQUEUE(&ipintrq, m); 1009 schednetisr(NETISR_IP); 1010 } 1011 splx(s); 1012#endif 1013 } 1014} 1015 1016/* 1017 * Process an ioctl request. 1018 */ 1019static int 1020slioctl(struct ifnet *ifp, u_long cmd, caddr_t data) 1021{ 1022 struct ifaddr *ifa = (struct ifaddr *)data; 1023 struct ifreq *ifr = (struct ifreq *)data; 1024 int s = splnet(), error = 0; 1025 struct sl_softc *sc = ifp->if_softc; 1026 struct ppp_stats *psp; 1027 struct ppp_comp_stats *pcp; 1028 1029 switch (cmd) { 1030 1031 case SIOCSIFADDR: 1032 if (ifa->ifa_addr->sa_family == AF_INET) 1033 ifp->if_flags |= IFF_UP; 1034 else 1035 error = EAFNOSUPPORT; 1036 break; 1037 1038 case SIOCSIFDSTADDR: 1039 if (ifa->ifa_addr->sa_family != AF_INET) 1040 error = EAFNOSUPPORT; 1041 break; 1042 1043 case SIOCSIFMTU: 1044 if ((ifr->ifr_mtu < 3) || (ifr->ifr_mtu > SLMAX)) { 1045 error = EINVAL; 1046 break; 1047 } 1048 sc->sc_if.if_mtu = ifr->ifr_mtu; 1049 break; 1050 1051 case SIOCGIFMTU: 1052 ifr->ifr_mtu = sc->sc_if.if_mtu; 1053 break; 1054 1055 case SIOCADDMULTI: 1056 case SIOCDELMULTI: 1057 if (ifr == 0) { 1058 error = EAFNOSUPPORT; /* XXX */ 1059 break; 1060 } 1061 switch (ifr->ifr_addr.sa_family) { 1062 1063#ifdef INET 1064 case AF_INET: 1065 break; 1066#endif 1067 1068 default: 1069 error = EAFNOSUPPORT; 1070 break; 1071 } 1072 break; 1073 1074 case SIOCGPPPSTATS: 1075 psp = &((struct ifpppstatsreq *) data)->stats; 1076 (void)memset(psp, 0, sizeof(*psp)); 1077 psp->p.ppp_ibytes = sc->sc_if.if_ibytes; 1078 psp->p.ppp_ipackets = sc->sc_if.if_ipackets; 1079 psp->p.ppp_ierrors = sc->sc_if.if_ierrors; 1080 psp->p.ppp_obytes = sc->sc_if.if_obytes; 1081 psp->p.ppp_opackets = sc->sc_if.if_opackets; 1082 psp->p.ppp_oerrors = sc->sc_if.if_oerrors; 1083#ifdef INET 1084 psp->vj.vjs_packets = sc->sc_comp.sls_packets; 1085 psp->vj.vjs_compressed = sc->sc_comp.sls_compressed; 1086 psp->vj.vjs_searches = sc->sc_comp.sls_searches; 1087 psp->vj.vjs_misses = sc->sc_comp.sls_misses; 1088 psp->vj.vjs_uncompressedin = sc->sc_comp.sls_uncompressedin; 1089 psp->vj.vjs_compressedin = sc->sc_comp.sls_compressedin; 1090 psp->vj.vjs_errorin = sc->sc_comp.sls_errorin; 1091 psp->vj.vjs_tossed = sc->sc_comp.sls_tossed; 1092#endif 1093 break; 1094 1095 case SIOCGPPPCSTATS: 1096 pcp = &((struct ifpppcstatsreq *) data)->stats; 1097 (void)memset(pcp, 0, sizeof(*pcp)); 1098 break; 1099 1100 default: 1101 error = EINVAL; 1102 } 1103 splx(s); 1104 return (error); 1105} 1106