1/* $NetBSD: if_sl.c,v 1.117 2010/04/05 07:22:23 joerg 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 1.117 2010/04/05 07:22:23 joerg Exp $"); 64 65#include "opt_inet.h" 66 67#include <sys/param.h> 68#include <sys/proc.h> 69#include <sys/malloc.h> 70#include <sys/mbuf.h> 71#include <sys/buf.h> 72#include <sys/dkstat.h> 73#include <sys/socket.h> 74#include <sys/ioctl.h> 75#include <sys/file.h> 76#include <sys/conf.h> 77#include <sys/tty.h> 78#include <sys/kernel.h> 79#include <sys/socketvar.h> 80#if __NetBSD__ 81#include <sys/systm.h> 82#include <sys/kauth.h> 83#endif 84#include <sys/cpu.h> 85#include <sys/intr.h> 86 87#include <net/if.h> 88#include <net/if_types.h> 89#include <net/netisr.h> 90#include <net/route.h> 91 92#ifdef INET 93#include <netinet/in.h> 94#include <netinet/in_systm.h> 95#include <netinet/in_var.h> 96#include <netinet/ip.h> 97#endif 98 99#include <net/slcompress.h> 100#include <net/if_slvar.h> 101#include <net/slip.h> 102#include <net/ppp_defs.h> 103#include <net/if_ppp.h> 104 105#include <sys/time.h> 106#include <net/bpf.h> 107 108/* 109 * SLMAX is a hard limit on input packet size. To simplify the code 110 * and improve performance, we require that packets fit in an mbuf 111 * cluster, and if we get a compressed packet, there's enough extra 112 * room to expand the header into a max length tcp/ip header (128 113 * bytes). So, SLMAX can be at most 114 * MCLBYTES - 128 115 * 116 * SLMTU is a hard limit on output packet size. To insure good 117 * interactive response, SLMTU wants to be the smallest size that 118 * amortizes the header cost. (Remember that even with 119 * type-of-service queuing, we have to wait for any in-progress 120 * packet to finish. I.e., we wait, on the average, 1/2 * mtu / 121 * cps, where cps is the line speed in characters per second. 122 * E.g., 533ms wait for a 1024 byte MTU on a 9600 baud line. The 123 * average compressed header size is 6-8 bytes so any MTU > 90 124 * bytes will give us 90% of the line bandwidth. A 100ms wait is 125 * tolerable (500ms is not), so want an MTU around 296. (Since TCP 126 * will send 256 byte segments (to allow for 40 byte headers), the 127 * typical packet size on the wire will be around 260 bytes). In 128 * 4.3tahoe+ systems, we can set an MTU in a route so we do that & 129 * leave the interface MTU relatively high (so we don't IP fragment 130 * when acting as a gateway to someone using a stupid MTU). 131 * 132 * Similar considerations apply to SLIP_HIWAT: It's the amount of 133 * data that will be queued 'downstream' of us (i.e., in clists 134 * waiting to be picked up by the tty output interrupt). If we 135 * queue a lot of data downstream, it's immune to our t.o.s. queuing. 136 * E.g., if SLIP_HIWAT is 1024, the interactive traffic in mixed 137 * telnet/ftp will see a 1 sec wait, independent of the mtu (the 138 * wait is dependent on the ftp window size but that's typically 139 * 1k - 4k). So, we want SLIP_HIWAT just big enough to amortize 140 * the cost (in idle time on the wire) of the tty driver running 141 * off the end of its clists & having to call back slstart for a 142 * new packet. For a tty interface with any buffering at all, this 143 * cost will be zero. Even with a totally brain dead interface (like 144 * the one on a typical workstation), the cost will be <= 1 character 145 * time. So, setting SLIP_HIWAT to ~100 guarantees that we'll lose 146 * at most 1% while maintaining good interactive response. 147 */ 148#define BUFOFFSET (128+sizeof(struct ifnet **)+SLIP_HDRLEN) 149#define SLMAX (MCLBYTES - BUFOFFSET) 150#define SLBUFSIZE (SLMAX + BUFOFFSET) 151#ifndef SLMTU 152#define SLMTU 296 153#endif 154#if (SLMTU < 3) 155#error SLMTU way too small. 156#endif 157#define SLIP_HIWAT roundup(50, TTROUND) 158#ifndef __NetBSD__ /* XXX - cgd */ 159#define CLISTRESERVE 1024 /* Can't let clists get too low */ 160#endif /* !__NetBSD__ */ 161 162/* 163 * SLIP ABORT ESCAPE MECHANISM: 164 * (inspired by HAYES modem escape arrangement) 165 * 1sec escape 1sec escape 1sec escape { 1sec escape 1sec escape } 166 * within window time signals a "soft" exit from slip mode by remote end 167 * if the IFF_DEBUG flag is on. 168 */ 169#define ABT_ESC '\033' /* can't be t_intr - distant host must know it*/ 170#define ABT_IDLE 1 /* in seconds - idle before an escape */ 171#define ABT_COUNT 3 /* count of escapes for abort */ 172#define ABT_WINDOW (ABT_COUNT*2+2) /* in seconds - time to count */ 173 174static int sl_clone_create(struct if_clone *, int); 175static int sl_clone_destroy(struct ifnet *); 176 177static LIST_HEAD(, sl_softc) sl_softc_list; 178 179struct if_clone sl_cloner = 180 IF_CLONE_INITIALIZER("sl", sl_clone_create, sl_clone_destroy); 181 182#define FRAME_END 0xc0 /* Frame End */ 183#define FRAME_ESCAPE 0xdb /* Frame Esc */ 184#define TRANS_FRAME_END 0xdc /* transposed frame end */ 185#define TRANS_FRAME_ESCAPE 0xdd /* transposed frame esc */ 186 187static void slintr(void *); 188 189static int slinit(struct sl_softc *); 190static struct mbuf *sl_btom(struct sl_softc *, int); 191 192static int slclose(struct tty *, int); 193static int slinput(int, struct tty *); 194static int slioctl(struct ifnet *, u_long, void *); 195static int slopen(dev_t, struct tty *); 196static int sloutput(struct ifnet *, struct mbuf *, const struct sockaddr *, 197 struct rtentry *); 198static int slstart(struct tty *); 199static int sltioctl(struct tty *, u_long, void *, int, struct lwp *); 200 201static struct linesw slip_disc = { 202 .l_name = "slip", 203 .l_open = slopen, 204 .l_close = slclose, 205 .l_read = ttyerrio, 206 .l_write = ttyerrio, 207 .l_ioctl = sltioctl, 208 .l_rint = slinput, 209 .l_start = slstart, 210 .l_modem = nullmodem, 211 .l_poll = ttyerrpoll 212}; 213 214void slattach(void); 215 216void 217slattach(void) 218{ 219 220 if (ttyldisc_attach(&slip_disc) != 0) 221 panic("slattach"); 222 LIST_INIT(&sl_softc_list); 223 if_clone_attach(&sl_cloner); 224} 225 226static int 227sl_clone_create(struct if_clone *ifc, int unit) 228{ 229 struct sl_softc *sc; 230 231 sc = malloc(sizeof(*sc), M_DEVBUF, M_WAIT|M_ZERO); 232 sc->sc_unit = unit; 233 if_initname(&sc->sc_if, ifc->ifc_name, unit); 234 sc->sc_if.if_softc = sc; 235 sc->sc_if.if_mtu = SLMTU; 236 sc->sc_if.if_flags = IFF_POINTOPOINT | SC_AUTOCOMP | IFF_MULTICAST; 237 sc->sc_if.if_type = IFT_SLIP; 238 sc->sc_if.if_ioctl = slioctl; 239 sc->sc_if.if_output = sloutput; 240 sc->sc_if.if_dlt = DLT_SLIP; 241 sc->sc_fastq.ifq_maxlen = 32; 242 IFQ_SET_READY(&sc->sc_if.if_snd); 243 if_attach(&sc->sc_if); 244 if_alloc_sadl(&sc->sc_if); 245 bpf_attach(&sc->sc_if, DLT_SLIP, SLIP_HDRLEN); 246 LIST_INSERT_HEAD(&sl_softc_list, sc, sc_iflist); 247 return 0; 248} 249 250static int 251sl_clone_destroy(struct ifnet *ifp) 252{ 253 struct sl_softc *sc = (struct sl_softc *)ifp->if_softc; 254 255 if (sc->sc_ttyp != NULL) 256 return EBUSY; /* Not removing it */ 257 258 LIST_REMOVE(sc, sc_iflist); 259 260 bpf_detach(ifp); 261 if_detach(ifp); 262 263 free(sc, M_DEVBUF); 264 return 0; 265} 266 267static int 268slinit(struct sl_softc *sc) 269{ 270 271 if (sc->sc_mbuf == NULL) { 272 sc->sc_mbuf = m_gethdr(M_WAIT, MT_DATA); 273 m_clget(sc->sc_mbuf, M_WAIT); 274 } 275 sc->sc_ep = (u_char *)sc->sc_mbuf->m_ext.ext_buf + 276 sc->sc_mbuf->m_ext.ext_size; 277 sc->sc_mp = sc->sc_pktstart = (u_char *)sc->sc_mbuf->m_ext.ext_buf + 278 BUFOFFSET; 279 280#ifdef INET 281 sl_compress_init(&sc->sc_comp); 282#endif 283 284 return 1; 285} 286 287/* 288 * Line specific open routine. 289 * Attach the given tty to the first available sl unit. 290 */ 291/* ARGSUSED */ 292static int 293slopen(dev_t dev, struct tty *tp) 294{ 295 struct lwp *l = curlwp; /* XXX */ 296 struct sl_softc *sc; 297 int error; 298 299 error = kauth_authorize_network(l->l_cred, KAUTH_NETWORK_INTERFACE_SLIP, 300 KAUTH_REQ_NETWORK_INTERFACE_SLIP_ADD, NULL, NULL, NULL); 301 if (error) 302 return error; 303 304 if (tp->t_linesw == &slip_disc) 305 return 0; 306 307 LIST_FOREACH(sc, &sl_softc_list, sc_iflist) 308 if (sc->sc_ttyp == NULL) { 309 sc->sc_si = softint_establish(SOFTINT_NET, 310 slintr, sc); 311 if (sc->sc_si == NULL) 312 return ENOMEM; 313 if (slinit(sc) == 0) { 314 softint_disestablish(sc->sc_si); 315 return ENOBUFS; 316 } 317 tp->t_sc = (void *)sc; 318 sc->sc_ttyp = tp; 319 sc->sc_if.if_baudrate = tp->t_ospeed; 320 mutex_spin_enter(&tty_lock); 321 tp->t_state |= TS_ISOPEN | TS_XCLUDE; 322 ttyflush(tp, FREAD | FWRITE); 323 /* 324 * make sure tty output queue is large enough 325 * to hold a full-sized packet (including frame 326 * end, and a possible extra frame end). full-sized 327 * packet occupies a max of 2*SLMAX bytes (because 328 * of possible escapes), and add two on for frame 329 * ends. 330 */ 331 if (tp->t_outq.c_cn < 2 * SLMAX + 2) { 332 sc->sc_oldbufsize = tp->t_outq.c_cn; 333 sc->sc_oldbufquot = tp->t_outq.c_cq != 0; 334 335 clfree(&tp->t_outq); 336 mutex_spin_exit(&tty_lock); 337 error = clalloc(&tp->t_outq, 2 * SLMAX + 2, 0); 338 if (error) { 339 softint_disestablish(sc->sc_si); 340 /* 341 * clalloc() might return -1 which 342 * is no good, so we need to return 343 * something else. 344 */ 345 return ENOMEM; /* XXX ?! */ 346 } 347 } else { 348 sc->sc_oldbufsize = sc->sc_oldbufquot = 0; 349 mutex_spin_exit(&tty_lock); 350 } 351 return 0; 352 } 353 return ENXIO; 354} 355 356/* 357 * Line specific close routine. 358 * Detach the tty from the sl unit. 359 */ 360static int 361slclose(struct tty *tp, int flag) 362{ 363 struct sl_softc *sc; 364 int s; 365 366 ttywflush(tp); 367 sc = tp->t_sc; 368 369 if (sc != NULL) { 370 softint_disestablish(sc->sc_si); 371 s = splnet(); 372 if_down(&sc->sc_if); 373 IF_PURGE(&sc->sc_fastq); 374 splx(s); 375 376 s = spltty(); 377 ttyldisc_release(tp->t_linesw); 378 tp->t_linesw = ttyldisc_default(); 379 tp->t_state = 0; 380 381 sc->sc_ttyp = NULL; 382 tp->t_sc = NULL; 383 384 m_freem(sc->sc_mbuf); 385 sc->sc_mbuf = NULL; 386 sc->sc_ep = sc->sc_mp = sc->sc_pktstart = NULL; 387 IF_PURGE(&sc->sc_inq); 388 389 /* 390 * If necessary, install a new outq buffer of the 391 * appropriate size. 392 */ 393 if (sc->sc_oldbufsize != 0) { 394 clfree(&tp->t_outq); 395 clalloc(&tp->t_outq, sc->sc_oldbufsize, 396 sc->sc_oldbufquot); 397 } 398 splx(s); 399 } 400 401 return 0; 402} 403 404/* 405 * Line specific (tty) ioctl routine. 406 * Provide a way to get the sl unit number. 407 */ 408/* ARGSUSED */ 409static int 410sltioctl(struct tty *tp, u_long cmd, void *data, int flag, 411 struct lwp *l) 412{ 413 struct sl_softc *sc = (struct sl_softc *)tp->t_sc; 414 415 switch (cmd) { 416 case SLIOCGUNIT: 417 *(int *)data = sc->sc_unit; /* XXX */ 418 break; 419 420 default: 421 return EPASSTHROUGH; 422 } 423 return 0; 424} 425 426/* 427 * Queue a packet. Start transmission if not active. 428 * Compression happens in slintr(); if we do it here, IP TOS 429 * will cause us to not compress "background" packets, because 430 * ordering gets trashed. It can be done for all packets in slintr(). 431 */ 432static int 433sloutput(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst, 434 struct rtentry *rtp) 435{ 436 struct sl_softc *sc = ifp->if_softc; 437 struct ip *ip; 438 struct ifqueue *ifq = NULL; 439 int s, error; 440 ALTQ_DECL(struct altq_pktattr pktattr;) 441 442 IFQ_CLASSIFY(&ifp->if_snd, m, dst->sa_family, &pktattr); 443 444 /* 445 * `Cannot happen' (see slioctl). Someday we will extend 446 * the line protocol to support other address families. 447 */ 448 if (dst->sa_family != AF_INET) { 449 printf("%s: af%d not supported\n", sc->sc_if.if_xname, 450 dst->sa_family); 451 m_freem(m); 452 sc->sc_if.if_noproto++; 453 return EAFNOSUPPORT; 454 } 455 456 if (sc->sc_ttyp == NULL) { 457 m_freem(m); 458 return ENETDOWN; /* sort of */ 459 } 460 if ((sc->sc_ttyp->t_state & TS_CARR_ON) == 0 && 461 (sc->sc_ttyp->t_cflag & CLOCAL) == 0) { 462 m_freem(m); 463 printf("%s: no carrier and not local\n", sc->sc_if.if_xname); 464 return EHOSTUNREACH; 465 } 466 ip = mtod(m, struct ip *); 467#ifdef INET 468 if (sc->sc_if.if_flags & SC_NOICMP && ip->ip_p == IPPROTO_ICMP) { 469 m_freem(m); 470 return ENETRESET; /* XXX ? */ 471 } 472#endif 473 474 s = spltty(); 475 if (sc->sc_oqlen && sc->sc_ttyp->t_outq.c_cc == sc->sc_oqlen) { 476 struct bintime bt; 477 478 /* if output's been stalled for too long, and restart */ 479 getbinuptime(&bt); 480 bintime_sub(&bt, &sc->sc_lastpacket); 481 if (bt.sec > 0) { 482 sc->sc_otimeout++; 483 slstart(sc->sc_ttyp); 484 } 485 } 486 splx(s); 487 488 s = splnet(); 489#ifdef INET 490 if ((ip->ip_tos & IPTOS_LOWDELAY) != 0) 491 ifq = &sc->sc_fastq; 492#endif 493 if ((error = ifq_enqueue2(ifp, ifq, m ALTQ_COMMA 494 ALTQ_DECL(&pktattr))) != 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 (IF_QFULL(&ipintrq)) { 939 IF_DROP(&ipintrq); 940 sc->sc_if.if_ierrors++; 941 sc->sc_if.if_iqdrops++; 942 m_freem(m); 943 } else { 944 IF_ENQUEUE(&ipintrq, m); 945 schednetisr(NETISR_IP); 946 } 947 splx(s); 948#endif 949 } 950 mutex_exit(softnet_lock); 951} 952 953/* 954 * Process an ioctl request. 955 */ 956static int 957slioctl(struct ifnet *ifp, u_long cmd, void *data) 958{ 959 struct ifaddr *ifa = (struct ifaddr *)data; 960 struct ifreq *ifr = (struct ifreq *)data; 961 int s = splnet(), error = 0; 962 struct sl_softc *sc = ifp->if_softc; 963 struct ppp_stats *psp; 964 struct ppp_comp_stats *pcp; 965 966 switch (cmd) { 967 968 case SIOCINITIFADDR: 969 if (ifa->ifa_addr->sa_family == AF_INET) 970 ifp->if_flags |= IFF_UP; 971 else 972 error = EAFNOSUPPORT; 973 break; 974 975 case SIOCSIFDSTADDR: 976 if (ifa->ifa_addr->sa_family != AF_INET) 977 error = EAFNOSUPPORT; 978 break; 979 980 case SIOCSIFMTU: 981 if ((ifr->ifr_mtu < 3) || (ifr->ifr_mtu > SLMAX)) { 982 error = EINVAL; 983 break; 984 } 985 /*FALLTHROUGH*/ 986 case SIOCGIFMTU: 987 if ((error = ifioctl_common(&sc->sc_if, cmd, data)) == ENETRESET) 988 error = 0; 989 break; 990 991 case SIOCADDMULTI: 992 case SIOCDELMULTI: 993 if (ifr == 0) { 994 error = EAFNOSUPPORT; /* XXX */ 995 break; 996 } 997 switch (ifreq_getaddr(cmd, ifr)->sa_family) { 998 999#ifdef INET 1000 case AF_INET: 1001 break; 1002#endif 1003 1004 default: 1005 error = EAFNOSUPPORT; 1006 break; 1007 } 1008 break; 1009 1010 case SIOCGPPPSTATS: 1011 psp = &((struct ifpppstatsreq *) data)->stats; 1012 (void)memset(psp, 0, sizeof(*psp)); 1013 psp->p.ppp_ibytes = sc->sc_if.if_ibytes; 1014 psp->p.ppp_ipackets = sc->sc_if.if_ipackets; 1015 psp->p.ppp_ierrors = sc->sc_if.if_ierrors; 1016 psp->p.ppp_obytes = sc->sc_if.if_obytes; 1017 psp->p.ppp_opackets = sc->sc_if.if_opackets; 1018 psp->p.ppp_oerrors = sc->sc_if.if_oerrors; 1019#ifdef INET 1020 psp->vj.vjs_packets = sc->sc_comp.sls_packets; 1021 psp->vj.vjs_compressed = sc->sc_comp.sls_compressed; 1022 psp->vj.vjs_searches = sc->sc_comp.sls_searches; 1023 psp->vj.vjs_misses = sc->sc_comp.sls_misses; 1024 psp->vj.vjs_uncompressedin = sc->sc_comp.sls_uncompressedin; 1025 psp->vj.vjs_compressedin = sc->sc_comp.sls_compressedin; 1026 psp->vj.vjs_errorin = sc->sc_comp.sls_errorin; 1027 psp->vj.vjs_tossed = sc->sc_comp.sls_tossed; 1028#endif 1029 break; 1030 1031 case SIOCGPPPCSTATS: 1032 pcp = &((struct ifpppcstatsreq *) data)->stats; 1033 (void)memset(pcp, 0, sizeof(*pcp)); 1034 break; 1035 1036 default: 1037 error = ifioctl_common(ifp, cmd, data); 1038 break; 1039 } 1040 splx(s); 1041 return error; 1042} 1043