if_sl.c revision 1.123
1/* $NetBSD: if_sl.c,v 1.123 2016/04/28 00:16:56 ozaki-r 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 1.123 2016/04/28 00:16:56 ozaki-r Exp $"); 64 65#ifdef _KERNEL_OPT 66#include "opt_inet.h" 67#endif 68 69#include <sys/param.h> 70#include <sys/proc.h> 71#include <sys/malloc.h> 72#include <sys/mbuf.h> 73#include <sys/buf.h> 74#include <sys/dkstat.h> 75#include <sys/socket.h> 76#include <sys/ioctl.h> 77#include <sys/file.h> 78#include <sys/conf.h> 79#include <sys/tty.h> 80#include <sys/kernel.h> 81#include <sys/socketvar.h> 82#if __NetBSD__ 83#include <sys/systm.h> 84#include <sys/kauth.h> 85#endif 86#include <sys/cpu.h> 87#include <sys/intr.h> 88 89#include <net/if.h> 90#include <net/if_types.h> 91#include <net/netisr.h> 92#include <net/route.h> 93 94#ifdef INET 95#include <netinet/in.h> 96#include <netinet/in_systm.h> 97#include <netinet/in_var.h> 98#include <netinet/ip.h> 99#endif 100 101#include <net/slcompress.h> 102#include <net/if_slvar.h> 103#include <net/slip.h> 104#include <net/ppp_defs.h> 105#include <net/if_ppp.h> 106 107#include <sys/time.h> 108#include <net/bpf.h> 109 110#include "ioconf.h" 111 112/* 113 * SLMAX is a hard limit on input packet size. To simplify the code 114 * and improve performance, we require that packets fit in an mbuf 115 * cluster, and if we get a compressed packet, there's enough extra 116 * room to expand the header into a max length tcp/ip header (128 117 * bytes). So, SLMAX can be at most 118 * MCLBYTES - 128 119 * 120 * SLMTU is a hard limit on output packet size. To insure good 121 * interactive response, SLMTU wants to be the smallest size that 122 * amortizes the header cost. (Remember that even with 123 * type-of-service queuing, we have to wait for any in-progress 124 * packet to finish. I.e., we wait, on the average, 1/2 * mtu / 125 * cps, where cps is the line speed in characters per second. 126 * E.g., 533ms wait for a 1024 byte MTU on a 9600 baud line. The 127 * average compressed header size is 6-8 bytes so any MTU > 90 128 * bytes will give us 90% of the line bandwidth. A 100ms wait is 129 * tolerable (500ms is not), so want an MTU around 296. (Since TCP 130 * will send 256 byte segments (to allow for 40 byte headers), the 131 * typical packet size on the wire will be around 260 bytes). In 132 * 4.3tahoe+ systems, we can set an MTU in a route so we do that & 133 * leave the interface MTU relatively high (so we don't IP fragment 134 * when acting as a gateway to someone using a stupid MTU). 135 * 136 * Similar considerations apply to SLIP_HIWAT: It's the amount of 137 * data that will be queued 'downstream' of us (i.e., in clists 138 * waiting to be picked up by the tty output interrupt). If we 139 * queue a lot of data downstream, it's immune to our t.o.s. queuing. 140 * E.g., if SLIP_HIWAT is 1024, the interactive traffic in mixed 141 * telnet/ftp will see a 1 sec wait, independent of the mtu (the 142 * wait is dependent on the ftp window size but that's typically 143 * 1k - 4k). So, we want SLIP_HIWAT just big enough to amortize 144 * the cost (in idle time on the wire) of the tty driver running 145 * off the end of its clists & having to call back slstart for a 146 * new packet. For a tty interface with any buffering at all, this 147 * cost will be zero. Even with a totally brain dead interface (like 148 * the one on a typical workstation), the cost will be <= 1 character 149 * time. So, setting SLIP_HIWAT to ~100 guarantees that we'll lose 150 * at most 1% while maintaining good interactive response. 151 */ 152#define BUFOFFSET (128+sizeof(struct ifnet **)+SLIP_HDRLEN) 153#define SLMAX (MCLBYTES - BUFOFFSET) 154#define SLBUFSIZE (SLMAX + BUFOFFSET) 155#ifndef SLMTU 156#define SLMTU 296 157#endif 158#if (SLMTU < 3) 159#error SLMTU way too small. 160#endif 161#define SLIP_HIWAT roundup(50, TTROUND) 162#ifndef __NetBSD__ /* XXX - cgd */ 163#define CLISTRESERVE 1024 /* Can't let clists get too low */ 164#endif /* !__NetBSD__ */ 165 166/* 167 * SLIP ABORT ESCAPE MECHANISM: 168 * (inspired by HAYES modem escape arrangement) 169 * 1sec escape 1sec escape 1sec escape { 1sec escape 1sec escape } 170 * within window time signals a "soft" exit from slip mode by remote end 171 * if the IFF_DEBUG flag is on. 172 */ 173#define ABT_ESC '\033' /* can't be t_intr - distant host must know it*/ 174#define ABT_IDLE 1 /* in seconds - idle before an escape */ 175#define ABT_COUNT 3 /* count of escapes for abort */ 176#define ABT_WINDOW (ABT_COUNT*2+2) /* in seconds - time to count */ 177 178static int sl_clone_create(struct if_clone *, int); 179static int sl_clone_destroy(struct ifnet *); 180 181static LIST_HEAD(, sl_softc) sl_softc_list; 182 183struct if_clone sl_cloner = 184 IF_CLONE_INITIALIZER("sl", sl_clone_create, sl_clone_destroy); 185 186#define FRAME_END 0xc0 /* Frame End */ 187#define FRAME_ESCAPE 0xdb /* Frame Esc */ 188#define TRANS_FRAME_END 0xdc /* transposed frame end */ 189#define TRANS_FRAME_ESCAPE 0xdd /* transposed frame esc */ 190 191static void slintr(void *); 192 193static int slinit(struct sl_softc *); 194static struct mbuf *sl_btom(struct sl_softc *, int); 195 196static int slclose(struct tty *, int); 197static int slinput(int, struct tty *); 198static int slioctl(struct ifnet *, u_long, void *); 199static int slopen(dev_t, struct tty *); 200static int sloutput(struct ifnet *, struct mbuf *, const struct sockaddr *, 201 const struct rtentry *); 202static int slstart(struct tty *); 203static int sltioctl(struct tty *, u_long, void *, int, struct lwp *); 204 205static struct linesw slip_disc = { 206 .l_name = "slip", 207 .l_open = slopen, 208 .l_close = slclose, 209 .l_read = ttyerrio, 210 .l_write = ttyerrio, 211 .l_ioctl = sltioctl, 212 .l_rint = slinput, 213 .l_start = slstart, 214 .l_modem = nullmodem, 215 .l_poll = ttyerrpoll 216}; 217 218void 219slattach(int n __unused) 220{ 221 222 if (ttyldisc_attach(&slip_disc) != 0) 223 panic("slattach"); 224 LIST_INIT(&sl_softc_list); 225 if_clone_attach(&sl_cloner); 226} 227 228static int 229sl_clone_create(struct if_clone *ifc, int unit) 230{ 231 struct sl_softc *sc; 232 233 sc = malloc(sizeof(*sc), M_DEVBUF, M_WAIT|M_ZERO); 234 sc->sc_unit = unit; 235 if_initname(&sc->sc_if, ifc->ifc_name, unit); 236 sc->sc_if.if_softc = sc; 237 sc->sc_if.if_mtu = SLMTU; 238 sc->sc_if.if_flags = IFF_POINTOPOINT | SC_AUTOCOMP | IFF_MULTICAST; 239 sc->sc_if.if_type = IFT_SLIP; 240 sc->sc_if.if_ioctl = slioctl; 241 sc->sc_if.if_output = sloutput; 242 sc->sc_if.if_dlt = DLT_SLIP; 243 sc->sc_fastq.ifq_maxlen = 32; 244 IFQ_SET_READY(&sc->sc_if.if_snd); 245 if_attach(&sc->sc_if); 246 if_alloc_sadl(&sc->sc_if); 247 bpf_attach(&sc->sc_if, DLT_SLIP, SLIP_HDRLEN); 248 LIST_INSERT_HEAD(&sl_softc_list, sc, sc_iflist); 249 return 0; 250} 251 252static int 253sl_clone_destroy(struct ifnet *ifp) 254{ 255 struct sl_softc *sc = (struct sl_softc *)ifp->if_softc; 256 257 if (sc->sc_ttyp != NULL) 258 return EBUSY; /* Not removing it */ 259 260 LIST_REMOVE(sc, sc_iflist); 261 262 bpf_detach(ifp); 263 if_detach(ifp); 264 265 free(sc, M_DEVBUF); 266 return 0; 267} 268 269static int 270slinit(struct sl_softc *sc) 271{ 272 273 if (sc->sc_mbuf == NULL) { 274 sc->sc_mbuf = m_gethdr(M_WAIT, MT_DATA); 275 m_clget(sc->sc_mbuf, M_WAIT); 276 } 277 sc->sc_ep = (u_char *)sc->sc_mbuf->m_ext.ext_buf + 278 sc->sc_mbuf->m_ext.ext_size; 279 sc->sc_mp = sc->sc_pktstart = (u_char *)sc->sc_mbuf->m_ext.ext_buf + 280 BUFOFFSET; 281 282#ifdef INET 283 sl_compress_init(&sc->sc_comp); 284#endif 285 286 return 1; 287} 288 289/* 290 * Line specific open routine. 291 * Attach the given tty to the first available sl unit. 292 */ 293/* ARGSUSED */ 294static int 295slopen(dev_t dev, struct tty *tp) 296{ 297 struct lwp *l = curlwp; /* XXX */ 298 struct sl_softc *sc; 299 int error; 300 301 error = kauth_authorize_network(l->l_cred, KAUTH_NETWORK_INTERFACE_SLIP, 302 KAUTH_REQ_NETWORK_INTERFACE_SLIP_ADD, NULL, NULL, NULL); 303 if (error) 304 return error; 305 306 if (tp->t_linesw == &slip_disc) 307 return 0; 308 309 LIST_FOREACH(sc, &sl_softc_list, sc_iflist) 310 if (sc->sc_ttyp == NULL) { 311 sc->sc_si = softint_establish(SOFTINT_NET, 312 slintr, sc); 313 if (sc->sc_si == NULL) 314 return ENOMEM; 315 if (slinit(sc) == 0) { 316 softint_disestablish(sc->sc_si); 317 return ENOBUFS; 318 } 319 tp->t_sc = (void *)sc; 320 sc->sc_ttyp = tp; 321 sc->sc_if.if_baudrate = tp->t_ospeed; 322 mutex_spin_enter(&tty_lock); 323 tp->t_state |= TS_ISOPEN | TS_XCLUDE; 324 ttyflush(tp, FREAD | FWRITE); 325 /* 326 * make sure tty output queue is large enough 327 * to hold a full-sized packet (including frame 328 * end, and a possible extra frame end). full-sized 329 * packet occupies a max of 2*SLMAX bytes (because 330 * of possible escapes), and add two on for frame 331 * ends. 332 */ 333 if (tp->t_outq.c_cn < 2 * SLMAX + 2) { 334 sc->sc_oldbufsize = tp->t_outq.c_cn; 335 sc->sc_oldbufquot = tp->t_outq.c_cq != 0; 336 337 clfree(&tp->t_outq); 338 mutex_spin_exit(&tty_lock); 339 error = clalloc(&tp->t_outq, 2 * SLMAX + 2, 0); 340 if (error) { 341 softint_disestablish(sc->sc_si); 342 /* 343 * clalloc() might return -1 which 344 * is no good, so we need to return 345 * something else. 346 */ 347 return ENOMEM; /* XXX ?! */ 348 } 349 } else { 350 sc->sc_oldbufsize = sc->sc_oldbufquot = 0; 351 mutex_spin_exit(&tty_lock); 352 } 353 return 0; 354 } 355 return ENXIO; 356} 357 358/* 359 * Line specific close routine. 360 * Detach the tty from the sl unit. 361 */ 362static int 363slclose(struct tty *tp, int flag) 364{ 365 struct sl_softc *sc; 366 int s; 367 368 ttywflush(tp); 369 sc = tp->t_sc; 370 371 if (sc != NULL) { 372 softint_disestablish(sc->sc_si); 373 s = splnet(); 374 if_down(&sc->sc_if); 375 IF_PURGE(&sc->sc_fastq); 376 splx(s); 377 378 s = spltty(); 379 ttyldisc_release(tp->t_linesw); 380 tp->t_linesw = ttyldisc_default(); 381 tp->t_state = 0; 382 383 sc->sc_ttyp = NULL; 384 tp->t_sc = NULL; 385 386 m_freem(sc->sc_mbuf); 387 sc->sc_mbuf = NULL; 388 sc->sc_ep = sc->sc_mp = sc->sc_pktstart = NULL; 389 IF_PURGE(&sc->sc_inq); 390 391 /* 392 * If necessary, install a new outq buffer of the 393 * appropriate size. 394 */ 395 if (sc->sc_oldbufsize != 0) { 396 clfree(&tp->t_outq); 397 clalloc(&tp->t_outq, sc->sc_oldbufsize, 398 sc->sc_oldbufquot); 399 } 400 splx(s); 401 } 402 403 return 0; 404} 405 406/* 407 * Line specific (tty) ioctl routine. 408 * Provide a way to get the sl unit number. 409 */ 410/* ARGSUSED */ 411static int 412sltioctl(struct tty *tp, u_long cmd, void *data, int flag, 413 struct lwp *l) 414{ 415 struct sl_softc *sc = (struct sl_softc *)tp->t_sc; 416 417 switch (cmd) { 418 case SLIOCGUNIT: 419 *(int *)data = sc->sc_unit; /* XXX */ 420 break; 421 422 default: 423 return EPASSTHROUGH; 424 } 425 return 0; 426} 427 428/* 429 * Queue a packet. Start transmission if not active. 430 * Compression happens in slintr(); if we do it here, IP TOS 431 * will cause us to not compress "background" packets, because 432 * ordering gets trashed. It can be done for all packets in slintr(). 433 */ 434static int 435sloutput(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst, 436 const struct rtentry *rtp) 437{ 438 struct sl_softc *sc = ifp->if_softc; 439 struct ip *ip; 440 struct ifqueue *ifq = NULL; 441 int s, error; 442 443 IFQ_CLASSIFY(&ifp->if_snd, m, dst->sa_family); 444 445 /* 446 * `Cannot happen' (see slioctl). Someday we will extend 447 * the line protocol to support other address families. 448 */ 449 if (dst->sa_family != AF_INET) { 450 printf("%s: af%d not supported\n", sc->sc_if.if_xname, 451 dst->sa_family); 452 m_freem(m); 453 sc->sc_if.if_noproto++; 454 return EAFNOSUPPORT; 455 } 456 457 if (sc->sc_ttyp == NULL) { 458 m_freem(m); 459 return ENETDOWN; /* sort of */ 460 } 461 if ((sc->sc_ttyp->t_state & TS_CARR_ON) == 0 && 462 (sc->sc_ttyp->t_cflag & CLOCAL) == 0) { 463 m_freem(m); 464 printf("%s: no carrier and not local\n", sc->sc_if.if_xname); 465 return EHOSTUNREACH; 466 } 467 ip = mtod(m, struct ip *); 468#ifdef INET 469 if (sc->sc_if.if_flags & SC_NOICMP && ip->ip_p == IPPROTO_ICMP) { 470 m_freem(m); 471 return ENETRESET; /* XXX ? */ 472 } 473#endif 474 475 s = spltty(); 476 if (sc->sc_oqlen && sc->sc_ttyp->t_outq.c_cc == sc->sc_oqlen) { 477 struct bintime bt; 478 479 /* if output's been stalled for too long, and restart */ 480 getbinuptime(&bt); 481 bintime_sub(&bt, &sc->sc_lastpacket); 482 if (bt.sec > 0) { 483 sc->sc_otimeout++; 484 slstart(sc->sc_ttyp); 485 } 486 } 487 splx(s); 488 489 s = splnet(); 490#ifdef INET 491 if ((ip->ip_tos & IPTOS_LOWDELAY) != 0) 492 ifq = &sc->sc_fastq; 493#endif 494 if ((error = ifq_enqueue2(ifp, ifq, m)) != 0) { 495 splx(s); 496 return error; 497 } 498 getbinuptime(&sc->sc_lastpacket); 499 splx(s); 500 501 s = spltty(); 502 if ((sc->sc_oqlen = sc->sc_ttyp->t_outq.c_cc) == 0) 503 slstart(sc->sc_ttyp); 504 splx(s); 505 506 return 0; 507} 508 509/* 510 * Start output on interface. Get another datagram 511 * to send from the interface queue and map it to 512 * the interface before starting output. 513 */ 514static int 515slstart(struct tty *tp) 516{ 517 struct sl_softc *sc = tp->t_sc; 518 519 /* 520 * If there is more in the output queue, just send it now. 521 * We are being called in lieu of ttstart and must do what 522 * it would. 523 */ 524 if (tp->t_outq.c_cc != 0) { 525 (*tp->t_oproc)(tp); 526 if (tp->t_outq.c_cc > SLIP_HIWAT) 527 return 0; 528 } 529 530 /* 531 * This happens briefly when the line shuts down. 532 */ 533 if (sc == NULL) 534 return 0; 535 softint_schedule(sc->sc_si); 536 return 0; 537} 538 539/* 540 * Copy data buffer to mbuf chain; add ifnet pointer. 541 */ 542static struct mbuf * 543sl_btom(struct sl_softc *sc, int len) 544{ 545 struct mbuf *m; 546 547 /* 548 * Allocate a new input buffer and swap. 549 */ 550 m = sc->sc_mbuf; 551 MGETHDR(sc->sc_mbuf, M_DONTWAIT, MT_DATA); 552 if (sc->sc_mbuf == NULL) { 553 sc->sc_mbuf = m; 554 return NULL; 555 } 556 MCLGET(sc->sc_mbuf, M_DONTWAIT); 557 if ((sc->sc_mbuf->m_flags & M_EXT) == 0) { 558 m_freem(sc->sc_mbuf); 559 sc->sc_mbuf = m; 560 return NULL; 561 } 562 sc->sc_ep = (u_char *)sc->sc_mbuf->m_ext.ext_buf + 563 sc->sc_mbuf->m_ext.ext_size; 564 565 m->m_data = sc->sc_pktstart; 566 567 m->m_pkthdr.len = m->m_len = len; 568 m->m_pkthdr.rcvif = &sc->sc_if; 569 return m; 570} 571 572/* 573 * tty interface receiver interrupt. 574 */ 575static int 576slinput(int c, struct tty *tp) 577{ 578 struct sl_softc *sc; 579 struct mbuf *m; 580 int len; 581 582 tk_nin++; 583 sc = (struct sl_softc *)tp->t_sc; 584 if (sc == NULL) 585 return 0; 586 if ((c & TTY_ERRORMASK) || ((tp->t_state & TS_CARR_ON) == 0 && 587 (tp->t_cflag & CLOCAL) == 0)) { 588 sc->sc_flags |= SC_ERROR; 589 return 0; 590 } 591 c &= TTY_CHARMASK; 592 593 ++sc->sc_if.if_ibytes; 594 595 if (sc->sc_if.if_flags & IFF_DEBUG) { 596 if (c == ABT_ESC) { 597 /* 598 * If we have a previous abort, see whether 599 * this one is within the time limit. 600 */ 601 if (sc->sc_abortcount && 602 time_second >= sc->sc_starttime + ABT_WINDOW) 603 sc->sc_abortcount = 0; 604 /* 605 * If we see an abort after "idle" time, count it; 606 * record when the first abort escape arrived. 607 */ 608 if (time_second >= sc->sc_lasttime + ABT_IDLE) { 609 if (++sc->sc_abortcount == 1) 610 sc->sc_starttime = time_second; 611 if (sc->sc_abortcount >= ABT_COUNT) { 612 slclose(tp, 0); 613 return 0; 614 } 615 } 616 } else 617 sc->sc_abortcount = 0; 618 sc->sc_lasttime = time_second; 619 } 620 621 switch (c) { 622 623 case TRANS_FRAME_ESCAPE: 624 if (sc->sc_escape) 625 c = FRAME_ESCAPE; 626 break; 627 628 case TRANS_FRAME_END: 629 if (sc->sc_escape) 630 c = FRAME_END; 631 break; 632 633 case FRAME_ESCAPE: 634 sc->sc_escape = 1; 635 return 0; 636 637 case FRAME_END: 638 if (sc->sc_flags & SC_ERROR) { 639 sc->sc_flags &= ~SC_ERROR; 640 goto newpack; 641 } 642 len = sc->sc_mp - sc->sc_pktstart; 643 if (len < 3) 644 /* less than min length packet - ignore */ 645 goto newpack; 646 647 m = sl_btom(sc, len); 648 if (m == NULL) 649 goto error; 650 651 IF_ENQUEUE(&sc->sc_inq, m); 652 softint_schedule(sc->sc_si); 653 goto newpack; 654 } 655 if (sc->sc_mp < sc->sc_ep) { 656 *sc->sc_mp++ = c; 657 sc->sc_escape = 0; 658 return 0; 659 } 660 661 /* can't put lower; would miss an extra frame */ 662 sc->sc_flags |= SC_ERROR; 663 664error: 665 sc->sc_if.if_ierrors++; 666newpack: 667 sc->sc_mp = sc->sc_pktstart = (u_char *)sc->sc_mbuf->m_ext.ext_buf + 668 BUFOFFSET; 669 sc->sc_escape = 0; 670 671 return 0; 672} 673 674static void 675slintr(void *arg) 676{ 677 struct sl_softc *sc = arg; 678 struct tty *tp = sc->sc_ttyp; 679 struct mbuf *m; 680 int s, len; 681 u_char *pktstart; 682#ifdef INET 683 u_char c; 684#endif 685 u_char chdr[CHDR_LEN]; 686 687 KASSERT(tp != NULL); 688 689 /* 690 * Output processing loop. 691 */ 692 mutex_enter(softnet_lock); 693 for (;;) { 694#ifdef INET 695 struct ip *ip; 696#endif 697 struct mbuf *m2; 698 struct mbuf *bpf_m; 699 700 /* 701 * Do not remove the packet from the queue if it 702 * doesn't look like it will fit into the current 703 * serial output queue. With a packet full of 704 * escapes, this could be as bad as MTU*2+2. 705 */ 706 s = spltty(); 707 if (tp->t_outq.c_cn - tp->t_outq.c_cc < 708 2 * sc->sc_if.if_mtu + 2) { 709 splx(s); 710 break; 711 } 712 splx(s); 713 714 /* 715 * Get a packet and send it to the interface. 716 */ 717 s = splnet(); 718 IF_DEQUEUE(&sc->sc_fastq, m); 719 if (m) 720 sc->sc_if.if_omcasts++; /* XXX */ 721 else 722 IFQ_DEQUEUE(&sc->sc_if.if_snd, m); 723 splx(s); 724 725 if (m == NULL) 726 break; 727 728 /* 729 * We do the header compression here rather than in 730 * sloutput() because the packets will be out of order 731 * if we are using TOS queueing, and the connection 732 * ID compression will get munged when this happens. 733 */ 734 if (sc->sc_if.if_bpf) { 735 /* 736 * We need to save the TCP/IP header before 737 * it's compressed. To avoid complicated 738 * code, we just make a deep copy of the 739 * entire packet (since this is a serial 740 * line, packets should be short and/or the 741 * copy should be negligible cost compared 742 * to the packet transmission time). 743 */ 744 bpf_m = m_dup(m, 0, M_COPYALL, M_DONTWAIT); 745 } else 746 bpf_m = NULL; 747#ifdef INET 748 if ((ip = mtod(m, struct ip *))->ip_p == IPPROTO_TCP) { 749 if (sc->sc_if.if_flags & SC_COMPRESS) 750 *mtod(m, u_char *) |= 751 sl_compress_tcp(m, ip, &sc->sc_comp, 1); 752 } 753#endif 754 if (bpf_m) 755 bpf_mtap_sl_out(&sc->sc_if, mtod(m, u_char *), bpf_m); 756 getbinuptime(&sc->sc_lastpacket); 757 758 s = spltty(); 759 760 /* 761 * The extra FRAME_END will start up a new packet, 762 * and thus will flush any accumulated garbage. We 763 * do this whenever the line may have been idle for 764 * some time. 765 */ 766 if (tp->t_outq.c_cc == 0) { 767 sc->sc_if.if_obytes++; 768 (void)putc(FRAME_END, &tp->t_outq); 769 } 770 771 while (m) { 772 u_char *bp, *cp, *ep; 773 774 bp = cp = mtod(m, u_char *); 775 ep = cp + m->m_len; 776 while (cp < ep) { 777 /* 778 * Find out how many bytes in the 779 * string we can handle without 780 * doing something special. 781 */ 782 while (cp < ep) { 783 switch (*cp++) { 784 case FRAME_ESCAPE: 785 case FRAME_END: 786 cp--; 787 goto out; 788 } 789 } 790 out: 791 if (cp > bp) { 792 /* 793 * Put N characters at once 794 * into the tty output queue. 795 */ 796 if (b_to_q(bp, cp - bp, &tp->t_outq)) 797 break; 798 sc->sc_if.if_obytes += cp - bp; 799 } 800 /* 801 * If there are characters left in 802 * the mbuf, the first one must be 803 * special.. Put it out in a different 804 * form. 805 */ 806 if (cp < ep) { 807 if (putc(FRAME_ESCAPE, &tp->t_outq)) 808 break; 809 if (putc(*cp++ == FRAME_ESCAPE ? 810 TRANS_FRAME_ESCAPE : 811 TRANS_FRAME_END, 812 &tp->t_outq)) { 813 (void)unputc(&tp->t_outq); 814 break; 815 } 816 sc->sc_if.if_obytes += 2; 817 } 818 bp = cp; 819 } 820 MFREE(m, m2); 821 m = m2; 822 } 823 824 if (putc(FRAME_END, &tp->t_outq)) { 825 /* 826 * Not enough room. Remove a char to make 827 * room and end the packet normally. If 828 * you get many collisions (more than one 829 * or two a day), you probably do not have 830 * enough clists and you should increase 831 * "nclist" in param.c 832 */ 833 (void)unputc(&tp->t_outq); 834 (void)putc(FRAME_END, &tp->t_outq); 835 sc->sc_if.if_collisions++; 836 } else { 837 sc->sc_if.if_obytes++; 838 sc->sc_if.if_opackets++; 839 } 840 841 /* 842 * We now have characters in the output queue, 843 * kick the serial port. 844 */ 845 (*tp->t_oproc)(tp); 846 splx(s); 847 } 848 849 /* 850 * Input processing loop. 851 */ 852 for (;;) { 853 s = spltty(); 854 IF_DEQUEUE(&sc->sc_inq, m); 855 splx(s); 856 if (m == NULL) 857 break; 858 pktstart = mtod(m, u_char *); 859 len = m->m_pkthdr.len; 860 if (sc->sc_if.if_bpf) { 861 /* 862 * Save the compressed header, so we 863 * can tack it on later. Note that we 864 * will end up copying garbage in some 865 * cases but this is okay. We remember 866 * where the buffer started so we can 867 * compute the new header length. 868 */ 869 memcpy(chdr, pktstart, CHDR_LEN); 870 } 871#ifdef INET 872 if ((c = (*pktstart & 0xf0)) != (IPVERSION << 4)) { 873 if (c & 0x80) 874 c = TYPE_COMPRESSED_TCP; 875 else if (c == TYPE_UNCOMPRESSED_TCP) 876 *pktstart &= 0x4f; /* XXX */ 877 /* 878 * We've got something that's not an IP 879 * packet. If compression is enabled, 880 * try to decompress it. Otherwise, if 881 * `auto-enable' compression is on and 882 * it's a reasonable packet, decompress 883 * it and then enable compression. 884 * Otherwise, drop it. 885 */ 886 if (sc->sc_if.if_flags & SC_COMPRESS) { 887 len = sl_uncompress_tcp(&pktstart, len, 888 (u_int)c, &sc->sc_comp); 889 if (len <= 0) { 890 m_freem(m); 891 continue; 892 } 893 } else if ((sc->sc_if.if_flags & SC_AUTOCOMP) && 894 c == TYPE_UNCOMPRESSED_TCP && len >= 40) { 895 len = sl_uncompress_tcp(&pktstart, len, 896 (u_int)c, &sc->sc_comp); 897 if (len <= 0) { 898 m_freem(m); 899 continue; 900 } 901 sc->sc_if.if_flags |= SC_COMPRESS; 902 } else { 903 m_freem(m); 904 continue; 905 } 906 } 907#endif 908 m->m_data = (void *) pktstart; 909 m->m_pkthdr.len = m->m_len = len; 910 if (sc->sc_if.if_bpf) { 911 bpf_mtap_sl_in(&sc->sc_if, chdr, &m); 912 if (m == NULL) 913 continue; 914 } 915 /* 916 * If the packet will fit into a single 917 * header mbuf, copy it into one, to save 918 * memory. 919 */ 920 if (m->m_pkthdr.len < MHLEN) { 921 struct mbuf *n; 922 int pktlen; 923 924 MGETHDR(n, M_DONTWAIT, MT_DATA); 925 pktlen = m->m_pkthdr.len; 926 M_MOVE_PKTHDR(n, m); 927 memcpy(mtod(n, void *), mtod(m, void *), pktlen); 928 n->m_len = m->m_len; 929 m_freem(m); 930 m = n; 931 } 932 933 sc->sc_if.if_ipackets++; 934 getbinuptime(&sc->sc_lastpacket); 935 936#ifdef INET 937 s = splnet(); 938 if (__predict_false(!pktq_enqueue(ip_pktq, m, 0))) { 939 sc->sc_if.if_ierrors++; 940 sc->sc_if.if_iqdrops++; 941 m_freem(m); 942 } 943 splx(s); 944#endif 945 } 946 mutex_exit(softnet_lock); 947} 948 949/* 950 * Process an ioctl request. 951 */ 952static int 953slioctl(struct ifnet *ifp, u_long cmd, void *data) 954{ 955 struct ifaddr *ifa = (struct ifaddr *)data; 956 struct ifreq *ifr = (struct ifreq *)data; 957 int s = splnet(), error = 0; 958 struct sl_softc *sc = ifp->if_softc; 959 struct ppp_stats *psp; 960 struct ppp_comp_stats *pcp; 961 962 switch (cmd) { 963 964 case SIOCINITIFADDR: 965 if (ifa->ifa_addr->sa_family == AF_INET) 966 ifp->if_flags |= IFF_UP; 967 else 968 error = EAFNOSUPPORT; 969 break; 970 971 case SIOCSIFDSTADDR: 972 if (ifa->ifa_addr->sa_family != AF_INET) 973 error = EAFNOSUPPORT; 974 break; 975 976 case SIOCSIFMTU: 977 if ((ifr->ifr_mtu < 3) || (ifr->ifr_mtu > SLMAX)) { 978 error = EINVAL; 979 break; 980 } 981 /*FALLTHROUGH*/ 982 case SIOCGIFMTU: 983 if ((error = ifioctl_common(&sc->sc_if, cmd, data)) == ENETRESET) 984 error = 0; 985 break; 986 987 case SIOCADDMULTI: 988 case SIOCDELMULTI: 989 if (ifr == 0) { 990 error = EAFNOSUPPORT; /* XXX */ 991 break; 992 } 993 switch (ifreq_getaddr(cmd, ifr)->sa_family) { 994 995#ifdef INET 996 case AF_INET: 997 break; 998#endif 999 1000 default: 1001 error = EAFNOSUPPORT; 1002 break; 1003 } 1004 break; 1005 1006 case SIOCGPPPSTATS: 1007 psp = &((struct ifpppstatsreq *) data)->stats; 1008 (void)memset(psp, 0, sizeof(*psp)); 1009 psp->p.ppp_ibytes = sc->sc_if.if_ibytes; 1010 psp->p.ppp_ipackets = sc->sc_if.if_ipackets; 1011 psp->p.ppp_ierrors = sc->sc_if.if_ierrors; 1012 psp->p.ppp_obytes = sc->sc_if.if_obytes; 1013 psp->p.ppp_opackets = sc->sc_if.if_opackets; 1014 psp->p.ppp_oerrors = sc->sc_if.if_oerrors; 1015#ifdef INET 1016 psp->vj.vjs_packets = sc->sc_comp.sls_packets; 1017 psp->vj.vjs_compressed = sc->sc_comp.sls_compressed; 1018 psp->vj.vjs_searches = sc->sc_comp.sls_searches; 1019 psp->vj.vjs_misses = sc->sc_comp.sls_misses; 1020 psp->vj.vjs_uncompressedin = sc->sc_comp.sls_uncompressedin; 1021 psp->vj.vjs_compressedin = sc->sc_comp.sls_compressedin; 1022 psp->vj.vjs_errorin = sc->sc_comp.sls_errorin; 1023 psp->vj.vjs_tossed = sc->sc_comp.sls_tossed; 1024#endif 1025 break; 1026 1027 case SIOCGPPPCSTATS: 1028 pcp = &((struct ifpppcstatsreq *) data)->stats; 1029 (void)memset(pcp, 0, sizeof(*pcp)); 1030 break; 1031 1032 default: 1033 error = ifioctl_common(ifp, cmd, data); 1034 break; 1035 } 1036 splx(s); 1037 return error; 1038} 1039