1 /* $NetBSD: if_sl.c,v 1.109 2007/11/10 18:29:36 ad 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 1.109 2007/11/10 18:29:36 ad 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 #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 #if NBPFILTER > 0 106 #include <sys/time.h> 107 #include <net/bpf.h> 108 #endif 109 110 /* 111 * SLMAX is a hard limit on input packet size. To simplify the code 112 * and improve performance, we require that packets fit in an mbuf 113 * cluster, and if we get a compressed packet, there's enough extra 114 * room to expand the header into a max length tcp/ip header (128 115 * bytes). So, SLMAX can be at most 116 * MCLBYTES - 128 117 * 118 * SLMTU is a hard limit on output packet size. To insure good 119 * interactive response, SLMTU wants to be the smallest size that 120 * amortizes the header cost. (Remember that even with 121 * type-of-service queuing, we have to wait for any in-progress 122 * packet to finish. I.e., we wait, on the average, 1/2 * mtu / 123 * cps, where cps is the line speed in characters per second. 124 * E.g., 533ms wait for a 1024 byte MTU on a 9600 baud line. The 125 * average compressed header size is 6-8 bytes so any MTU > 90 126 * bytes will give us 90% of the line bandwidth. A 100ms wait is 127 * tolerable (500ms is not), so want an MTU around 296. (Since TCP 128 * will send 256 byte segments (to allow for 40 byte headers), the 129 * typical packet size on the wire will be around 260 bytes). In 130 * 4.3tahoe+ systems, we can set an MTU in a route so we do that & 131 * leave the interface MTU relatively high (so we don't IP fragment 132 * when acting as a gateway to someone using a stupid MTU). 133 * 134 * Similar considerations apply to SLIP_HIWAT: It's the amount of 135 * data that will be queued 'downstream' of us (i.e., in clists 136 * waiting to be picked up by the tty output interrupt). If we 137 * queue a lot of data downstream, it's immune to our t.o.s. queuing. 138 * E.g., if SLIP_HIWAT is 1024, the interactive traffic in mixed 139 * telnet/ftp will see a 1 sec wait, independent of the mtu (the 140 * wait is dependent on the ftp window size but that's typically 141 * 1k - 4k). So, we want SLIP_HIWAT just big enough to amortize 142 * the cost (in idle time on the wire) of the tty driver running 143 * off the end of its clists & having to call back slstart for a 144 * new packet. For a tty interface with any buffering at all, this 145 * cost will be zero. Even with a totally brain dead interface (like 146 * the one on a typical workstation), the cost will be <= 1 character 147 * time. So, setting SLIP_HIWAT to ~100 guarantees that we'll lose 148 * at most 1% while maintaining good interactive response. 149 */ 150 #define BUFOFFSET (128+sizeof(struct ifnet **)+SLIP_HDRLEN) 151 #define SLMAX (MCLBYTES - BUFOFFSET) 152 #define SLBUFSIZE (SLMAX + BUFOFFSET) 153 #ifndef SLMTU 154 #define SLMTU 296 155 #endif 156 #if (SLMTU < 3) 157 #error SLMTU way too small. 158 #endif 159 #define SLIP_HIWAT roundup(50,CBSIZE) 160 #ifndef __NetBSD__ /* XXX - cgd */ 161 #define CLISTRESERVE 1024 /* Can't let clists get too low */ 162 #endif /* !__NetBSD__ */ 163 164 /* 165 * SLIP ABORT ESCAPE MECHANISM: 166 * (inspired by HAYES modem escape arrangement) 167 * 1sec escape 1sec escape 1sec escape { 1sec escape 1sec escape } 168 * within window time signals a "soft" exit from slip mode by remote end 169 * if the IFF_DEBUG flag is on. 170 */ 171 #define ABT_ESC '\033' /* can't be t_intr - distant host must know it*/ 172 #define ABT_IDLE 1 /* in seconds - idle before an escape */ 173 #define ABT_COUNT 3 /* count of escapes for abort */ 174 #define ABT_WINDOW (ABT_COUNT*2+2) /* in seconds - time to count */ 175 176 static int sl_clone_create(struct if_clone *, int); 177 static int sl_clone_destroy(struct ifnet *); 178 179 static LIST_HEAD(, sl_softc) sl_softc_list; 180 181 struct if_clone sl_cloner = 182 IF_CLONE_INITIALIZER("sl", sl_clone_create, sl_clone_destroy); 183 184 #define FRAME_END 0xc0 /* Frame End */ 185 #define FRAME_ESCAPE 0xdb /* Frame Esc */ 186 #define TRANS_FRAME_END 0xdc /* transposed frame end */ 187 #define TRANS_FRAME_ESCAPE 0xdd /* transposed frame esc */ 188 189 static void slintr(void *); 190 191 static int slinit(struct sl_softc *); 192 static struct mbuf *sl_btom(struct sl_softc *, int); 193 194 static int slclose(struct tty *, int); 195 static int slinput(int, struct tty *); 196 static int slioctl(struct ifnet *, u_long, void *); 197 static int slopen(dev_t, struct tty *); 198 static int sloutput(struct ifnet *, struct mbuf *, const struct sockaddr *, 199 struct rtentry *); 200 static int slstart(struct tty *); 201 static int sltioctl(struct tty *, u_long, void *, int, struct lwp *); 202 203 static struct linesw slip_disc = { 204 .l_name = "slip", 205 .l_open = slopen, 206 .l_close = slclose, 207 .l_read = ttyerrio, 208 .l_write = ttyerrio, 209 .l_ioctl = sltioctl, 210 .l_rint = slinput, 211 .l_start = slstart, 212 .l_modem = nullmodem, 213 .l_poll = ttyerrpoll 214 }; 215 216 void slattach(void); 217 218 void 219 slattach(void) 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 } 227 228 static int 229 sl_clone_create(struct if_clone *ifc, int unit) 230 { 231 struct sl_softc *sc; 232 233 MALLOC(sc, struct sl_softc *, sizeof(*sc), M_DEVBUF, M_WAIT|M_ZERO); 234 sc->sc_unit = unit; 235 (void)snprintf(sc->sc_if.if_xname, sizeof(sc->sc_if.if_xname), 236 "%s%d", ifc->ifc_name, unit); 237 sc->sc_if.if_softc = sc; 238 sc->sc_if.if_mtu = SLMTU; 239 sc->sc_if.if_flags = IFF_POINTOPOINT | SC_AUTOCOMP | IFF_MULTICAST; 240 sc->sc_if.if_type = IFT_SLIP; 241 sc->sc_if.if_ioctl = slioctl; 242 sc->sc_if.if_output = sloutput; 243 sc->sc_if.if_dlt = DLT_SLIP; 244 sc->sc_fastq.ifq_maxlen = 32; 245 IFQ_SET_READY(&sc->sc_if.if_snd); 246 if_attach(&sc->sc_if); 247 if_alloc_sadl(&sc->sc_if); 248 #if NBPFILTER > 0 249 bpfattach(&sc->sc_if, DLT_SLIP, SLIP_HDRLEN); 250 #endif 251 LIST_INSERT_HEAD(&sl_softc_list, sc, sc_iflist); 252 return 0; 253 } 254 255 static int 256 sl_clone_destroy(struct ifnet *ifp) 257 { 258 struct sl_softc *sc = (struct sl_softc *)ifp->if_softc; 259 260 if (sc->sc_ttyp != NULL) 261 return EBUSY; /* Not removing it */ 262 263 LIST_REMOVE(sc, sc_iflist); 264 265 #if NBPFILTER > 0 266 bpfdetach(ifp); 267 #endif 268 if_detach(ifp); 269 270 FREE(sc, M_DEVBUF); 271 return 0; 272 } 273 274 static int 275 slinit(struct sl_softc *sc) 276 { 277 278 if (sc->sc_mbuf == NULL) { 279 sc->sc_mbuf = m_gethdr(M_WAIT, MT_DATA); 280 m_clget(sc->sc_mbuf, M_WAIT); 281 } 282 sc->sc_ep = (u_char *)sc->sc_mbuf->m_ext.ext_buf + 283 sc->sc_mbuf->m_ext.ext_size; 284 sc->sc_mp = sc->sc_pktstart = (u_char *)sc->sc_mbuf->m_ext.ext_buf + 285 BUFOFFSET; 286 287 #ifdef INET 288 sl_compress_init(&sc->sc_comp); 289 #endif 290 291 return 1; 292 } 293 294 /* 295 * Line specific open routine. 296 * Attach the given tty to the first available sl unit. 297 */ 298 /* ARGSUSED */ 299 static int 300 slopen(dev_t dev, struct tty *tp) 301 { 302 struct lwp *l = curlwp; /* XXX */ 303 struct sl_softc *sc; 304 int error; 305 306 if ((error = kauth_authorize_generic(l->l_cred, KAUTH_GENERIC_ISSUSER, 307 NULL)) != 0) 308 return error; 309 310 if (tp->t_linesw == &slip_disc) 311 return 0; 312 313 LIST_FOREACH(sc, &sl_softc_list, sc_iflist) 314 if (sc->sc_ttyp == NULL) { 315 sc->sc_si = softint_establish(SOFTINT_NET, 316 slintr, sc); 317 if (sc->sc_si == NULL) 318 return ENOMEM; 319 if (slinit(sc) == 0) { 320 softint_disestablish(sc->sc_si); 321 return ENOBUFS; 322 } 323 tp->t_sc = (void *)sc; 324 sc->sc_ttyp = tp; 325 sc->sc_if.if_baudrate = tp->t_ospeed; 326 mutex_spin_enter(&tty_lock); 327 tp->t_state |= TS_ISOPEN | TS_XCLUDE; 328 ttyflush(tp, FREAD | FWRITE); 329 /* 330 * make sure tty output queue is large enough 331 * to hold a full-sized packet (including frame 332 * end, and a possible extra frame end). full-sized 333 * packet occupies a max of 2*SLMAX bytes (because 334 * of possible escapes), and add two on for frame 335 * ends. 336 */ 337 if (tp->t_outq.c_cn < 2 * SLMAX + 2) { 338 sc->sc_oldbufsize = tp->t_outq.c_cn; 339 sc->sc_oldbufquot = tp->t_outq.c_cq != 0; 340 341 clfree(&tp->t_outq); 342 mutex_spin_exit(&tty_lock); 343 error = clalloc(&tp->t_outq, 2 * SLMAX + 2, 0); 344 if (error) { 345 softint_disestablish(sc->sc_si); 346 /* 347 * clalloc() might return -1 which 348 * is no good, so we need to return 349 * something else. 350 */ 351 return ENOMEM; /* XXX ?! */ 352 } 353 } else { 354 sc->sc_oldbufsize = sc->sc_oldbufquot = 0; 355 mutex_spin_exit(&tty_lock); 356 } 357 return 0; 358 } 359 return ENXIO; 360 } 361 362 /* 363 * Line specific close routine. 364 * Detach the tty from the sl unit. 365 */ 366 static int 367 slclose(struct tty *tp, int flag) 368 { 369 struct sl_softc *sc; 370 int s; 371 372 ttywflush(tp); 373 sc = tp->t_sc; 374 375 if (sc != NULL) { 376 softint_disestablish(sc->sc_si); 377 s = splnet(); 378 if_down(&sc->sc_if); 379 IF_PURGE(&sc->sc_fastq); 380 splx(s); 381 382 s = spltty(); 383 ttyldisc_release(tp->t_linesw); 384 tp->t_linesw = ttyldisc_default(); 385 tp->t_state = 0; 386 387 sc->sc_ttyp = NULL; 388 tp->t_sc = NULL; 389 390 m_freem(sc->sc_mbuf); 391 sc->sc_mbuf = NULL; 392 sc->sc_ep = sc->sc_mp = sc->sc_pktstart = NULL; 393 IF_PURGE(&sc->sc_inq); 394 395 /* 396 * If necessary, install a new outq buffer of the 397 * appropriate size. 398 */ 399 if (sc->sc_oldbufsize != 0) { 400 clfree(&tp->t_outq); 401 clalloc(&tp->t_outq, sc->sc_oldbufsize, 402 sc->sc_oldbufquot); 403 } 404 splx(s); 405 } 406 407 return 0; 408 } 409 410 /* 411 * Line specific (tty) ioctl routine. 412 * Provide a way to get the sl unit number. 413 */ 414 /* ARGSUSED */ 415 static int 416 sltioctl(struct tty *tp, u_long cmd, void *data, int flag, 417 struct lwp *l) 418 { 419 struct sl_softc *sc = (struct sl_softc *)tp->t_sc; 420 421 switch (cmd) { 422 case SLIOCGUNIT: 423 *(int *)data = sc->sc_unit; /* XXX */ 424 break; 425 426 default: 427 return EPASSTHROUGH; 428 } 429 return 0; 430 } 431 432 /* 433 * Queue a packet. Start transmission if not active. 434 * Compression happens in slintr(); if we do it here, IP TOS 435 * will cause us to not compress "background" packets, because 436 * ordering gets trashed. It can be done for all packets in slintr(). 437 */ 438 static int 439 sloutput(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst, 440 struct rtentry *rtp) 441 { 442 struct sl_softc *sc = ifp->if_softc; 443 struct ip *ip; 444 struct ifqueue *ifq = NULL; 445 int s, error; 446 ALTQ_DECL(struct altq_pktattr pktattr;) 447 448 IFQ_CLASSIFY(&ifp->if_snd, m, dst->sa_family, &pktattr); 449 450 /* 451 * `Cannot happen' (see slioctl). Someday we will extend 452 * the line protocol to support other address families. 453 */ 454 if (dst->sa_family != AF_INET) { 455 printf("%s: af%d not supported\n", sc->sc_if.if_xname, 456 dst->sa_family); 457 m_freem(m); 458 sc->sc_if.if_noproto++; 459 return EAFNOSUPPORT; 460 } 461 462 if (sc->sc_ttyp == NULL) { 463 m_freem(m); 464 return ENETDOWN; /* sort of */ 465 } 466 if ((sc->sc_ttyp->t_state & TS_CARR_ON) == 0 && 467 (sc->sc_ttyp->t_cflag & CLOCAL) == 0) { 468 m_freem(m); 469 printf("%s: no carrier and not local\n", sc->sc_if.if_xname); 470 return EHOSTUNREACH; 471 } 472 ip = mtod(m, struct ip *); 473 #ifdef INET 474 if (sc->sc_if.if_flags & SC_NOICMP && ip->ip_p == IPPROTO_ICMP) { 475 m_freem(m); 476 return ENETRESET; /* XXX ? */ 477 } 478 #endif 479 480 s = spltty(); 481 if (sc->sc_oqlen && sc->sc_ttyp->t_outq.c_cc == sc->sc_oqlen) { 482 struct bintime bt; 483 484 /* if output's been stalled for too long, and restart */ 485 getbinuptime(&bt); 486 bintime_sub(&bt, &sc->sc_lastpacket); 487 if (bt.sec > 0) { 488 sc->sc_otimeout++; 489 slstart(sc->sc_ttyp); 490 } 491 } 492 splx(s); 493 494 s = splnet(); 495 #ifdef INET 496 if ((ip->ip_tos & IPTOS_LOWDELAY) != 0) 497 ifq = &sc->sc_fastq; 498 #endif 499 if ((error = ifq_enqueue2(ifp, ifq, m ALTQ_COMMA 500 ALTQ_DECL(&pktattr))) != 0) { 501 splx(s); 502 return error; 503 } 504 getbinuptime(&sc->sc_lastpacket); 505 splx(s); 506 507 s = spltty(); 508 if ((sc->sc_oqlen = sc->sc_ttyp->t_outq.c_cc) == 0) 509 slstart(sc->sc_ttyp); 510 splx(s); 511 512 return 0; 513 } 514 515 /* 516 * Start output on interface. Get another datagram 517 * to send from the interface queue and map it to 518 * the interface before starting output. 519 */ 520 static int 521 slstart(struct tty *tp) 522 { 523 struct sl_softc *sc = tp->t_sc; 524 525 /* 526 * If there is more in the output queue, just send it now. 527 * We are being called in lieu of ttstart and must do what 528 * it would. 529 */ 530 if (tp->t_outq.c_cc != 0) { 531 (*tp->t_oproc)(tp); 532 if (tp->t_outq.c_cc > SLIP_HIWAT) 533 return 0; 534 } 535 536 /* 537 * This happens briefly when the line shuts down. 538 */ 539 if (sc == NULL) 540 return 0; 541 softint_schedule(sc->sc_si); 542 return 0; 543 } 544 545 /* 546 * Copy data buffer to mbuf chain; add ifnet pointer. 547 */ 548 static struct mbuf * 549 sl_btom(struct sl_softc *sc, int len) 550 { 551 struct mbuf *m; 552 553 /* 554 * Allocate a new input buffer and swap. 555 */ 556 m = sc->sc_mbuf; 557 MGETHDR(sc->sc_mbuf, M_DONTWAIT, MT_DATA); 558 if (sc->sc_mbuf == NULL) { 559 sc->sc_mbuf = m; 560 return NULL; 561 } 562 MCLGET(sc->sc_mbuf, M_DONTWAIT); 563 if ((sc->sc_mbuf->m_flags & M_EXT) == 0) { 564 m_freem(sc->sc_mbuf); 565 sc->sc_mbuf = m; 566 return NULL; 567 } 568 sc->sc_ep = (u_char *)sc->sc_mbuf->m_ext.ext_buf + 569 sc->sc_mbuf->m_ext.ext_size; 570 571 m->m_data = sc->sc_pktstart; 572 573 m->m_pkthdr.len = m->m_len = len; 574 m->m_pkthdr.rcvif = &sc->sc_if; 575 return m; 576 } 577 578 /* 579 * tty interface receiver interrupt. 580 */ 581 static int 582 slinput(int c, struct tty *tp) 583 { 584 struct sl_softc *sc; 585 struct mbuf *m; 586 int len; 587 588 tk_nin++; 589 sc = (struct sl_softc *)tp->t_sc; 590 if (sc == NULL) 591 return 0; 592 if ((c & TTY_ERRORMASK) || ((tp->t_state & TS_CARR_ON) == 0 && 593 (tp->t_cflag & CLOCAL) == 0)) { 594 sc->sc_flags |= SC_ERROR; 595 return 0; 596 } 597 c &= TTY_CHARMASK; 598 599 ++sc->sc_if.if_ibytes; 600 601 if (sc->sc_if.if_flags & IFF_DEBUG) { 602 if (c == ABT_ESC) { 603 /* 604 * If we have a previous abort, see whether 605 * this one is within the time limit. 606 */ 607 if (sc->sc_abortcount && 608 time_second >= sc->sc_starttime + ABT_WINDOW) 609 sc->sc_abortcount = 0; 610 /* 611 * If we see an abort after "idle" time, count it; 612 * record when the first abort escape arrived. 613 */ 614 if (time_second >= sc->sc_lasttime + ABT_IDLE) { 615 if (++sc->sc_abortcount == 1) 616 sc->sc_starttime = time_second; 617 if (sc->sc_abortcount >= ABT_COUNT) { 618 slclose(tp, 0); 619 return 0; 620 } 621 } 622 } else 623 sc->sc_abortcount = 0; 624 sc->sc_lasttime = time_second; 625 } 626 627 switch (c) { 628 629 case TRANS_FRAME_ESCAPE: 630 if (sc->sc_escape) 631 c = FRAME_ESCAPE; 632 break; 633 634 case TRANS_FRAME_END: 635 if (sc->sc_escape) 636 c = FRAME_END; 637 break; 638 639 case FRAME_ESCAPE: 640 sc->sc_escape = 1; 641 return 0; 642 643 case FRAME_END: 644 if (sc->sc_flags & SC_ERROR) { 645 sc->sc_flags &= ~SC_ERROR; 646 goto newpack; 647 } 648 len = sc->sc_mp - sc->sc_pktstart; 649 if (len < 3) 650 /* less than min length packet - ignore */ 651 goto newpack; 652 653 m = sl_btom(sc, len); 654 if (m == NULL) 655 goto error; 656 657 IF_ENQUEUE(&sc->sc_inq, m); 658 softint_schedule(sc->sc_si); 659 goto newpack; 660 } 661 if (sc->sc_mp < sc->sc_ep) { 662 *sc->sc_mp++ = c; 663 sc->sc_escape = 0; 664 return 0; 665 } 666 667 /* can't put lower; would miss an extra frame */ 668 sc->sc_flags |= SC_ERROR; 669 670 error: 671 sc->sc_if.if_ierrors++; 672 newpack: 673 sc->sc_mp = sc->sc_pktstart = (u_char *)sc->sc_mbuf->m_ext.ext_buf + 674 BUFOFFSET; 675 sc->sc_escape = 0; 676 677 return 0; 678 } 679 680 static void 681 slintr(void *arg) 682 { 683 struct sl_softc *sc = arg; 684 struct tty *tp = sc->sc_ttyp; 685 struct mbuf *m; 686 int s, len; 687 u_char *pktstart; 688 #ifdef INET 689 u_char c; 690 #endif 691 #if NBPFILTER > 0 692 u_char chdr[CHDR_LEN]; 693 #endif 694 695 KASSERT(tp != NULL); 696 697 /* 698 * Output processing loop. 699 */ 700 for (;;) { 701 #ifdef INET 702 struct ip *ip; 703 #endif 704 struct mbuf *m2; 705 #if NBPFILTER > 0 706 struct mbuf *bpf_m; 707 #endif 708 709 /* 710 * Do not remove the packet from the queue if it 711 * doesn't look like it will fit into the current 712 * serial output queue. With a packet full of 713 * escapes, this could be as bad as MTU*2+2. 714 */ 715 s = spltty(); 716 if (tp->t_outq.c_cn - tp->t_outq.c_cc < 717 2 * sc->sc_if.if_mtu + 2) { 718 splx(s); 719 break; 720 } 721 splx(s); 722 723 /* 724 * Get a packet and send it to the interface. 725 */ 726 s = splnet(); 727 IF_DEQUEUE(&sc->sc_fastq, m); 728 if (m) 729 sc->sc_if.if_omcasts++; /* XXX */ 730 else 731 IFQ_DEQUEUE(&sc->sc_if.if_snd, m); 732 splx(s); 733 734 if (m == NULL) 735 break; 736 737 /* 738 * We do the header compression here rather than in 739 * sloutput() because the packets will be out of order 740 * if we are using TOS queueing, and the connection 741 * ID compression will get munged when this happens. 742 */ 743 #if NBPFILTER > 0 744 if (sc->sc_if.if_bpf) { 745 /* 746 * We need to save the TCP/IP header before 747 * it's compressed. To avoid complicated 748 * code, we just make a deep copy of the 749 * entire packet (since this is a serial 750 * line, packets should be short and/or the 751 * copy should be negligible cost compared 752 * to the packet transmission time). 753 */ 754 bpf_m = m_dup(m, 0, M_COPYALL, M_DONTWAIT); 755 } else 756 bpf_m = NULL; 757 #endif 758 #ifdef INET 759 if ((ip = mtod(m, struct ip *))->ip_p == IPPROTO_TCP) { 760 if (sc->sc_if.if_flags & SC_COMPRESS) 761 *mtod(m, u_char *) |= 762 sl_compress_tcp(m, ip, &sc->sc_comp, 1); 763 } 764 #endif 765 #if NBPFILTER > 0 766 if (sc->sc_if.if_bpf && bpf_m != NULL) 767 bpf_mtap_sl_out(sc->sc_if.if_bpf, mtod(m, u_char *), 768 bpf_m); 769 #endif 770 getbinuptime(&sc->sc_lastpacket); 771 772 s = spltty(); 773 774 /* 775 * The extra FRAME_END will start up a new packet, 776 * and thus will flush any accumulated garbage. We 777 * do this whenever the line may have been idle for 778 * some time. 779 */ 780 if (tp->t_outq.c_cc == 0) { 781 sc->sc_if.if_obytes++; 782 (void)putc(FRAME_END, &tp->t_outq); 783 } 784 785 while (m) { 786 u_char *bp, *cp, *ep; 787 788 bp = cp = mtod(m, u_char *); 789 ep = cp + m->m_len; 790 while (cp < ep) { 791 /* 792 * Find out how many bytes in the 793 * string we can handle without 794 * doing something special. 795 */ 796 while (cp < ep) { 797 switch (*cp++) { 798 case FRAME_ESCAPE: 799 case FRAME_END: 800 cp--; 801 goto out; 802 } 803 } 804 out: 805 if (cp > bp) { 806 /* 807 * Put N characters at once 808 * into the tty output queue. 809 */ 810 if (b_to_q(bp, cp - bp, &tp->t_outq)) 811 break; 812 sc->sc_if.if_obytes += cp - bp; 813 } 814 /* 815 * If there are characters left in 816 * the mbuf, the first one must be 817 * special.. Put it out in a different 818 * form. 819 */ 820 if (cp < ep) { 821 if (putc(FRAME_ESCAPE, &tp->t_outq)) 822 break; 823 if (putc(*cp++ == FRAME_ESCAPE ? 824 TRANS_FRAME_ESCAPE : 825 TRANS_FRAME_END, 826 &tp->t_outq)) { 827 (void)unputc(&tp->t_outq); 828 break; 829 } 830 sc->sc_if.if_obytes += 2; 831 } 832 bp = cp; 833 } 834 MFREE(m, m2); 835 m = m2; 836 } 837 838 if (putc(FRAME_END, &tp->t_outq)) { 839 /* 840 * Not enough room. Remove a char to make 841 * room and end the packet normally. If 842 * you get many collisions (more than one 843 * or two a day), you probably do not have 844 * enough clists and you should increase 845 * "nclist" in param.c 846 */ 847 (void)unputc(&tp->t_outq); 848 (void)putc(FRAME_END, &tp->t_outq); 849 sc->sc_if.if_collisions++; 850 } else { 851 sc->sc_if.if_obytes++; 852 sc->sc_if.if_opackets++; 853 } 854 855 /* 856 * We now have characters in the output queue, 857 * kick the serial port. 858 */ 859 (*tp->t_oproc)(tp); 860 splx(s); 861 } 862 863 /* 864 * Input processing loop. 865 */ 866 for (;;) { 867 s = spltty(); 868 IF_DEQUEUE(&sc->sc_inq, m); 869 splx(s); 870 if (m == NULL) 871 break; 872 pktstart = mtod(m, u_char *); 873 len = m->m_pkthdr.len; 874 #if NBPFILTER > 0 875 if (sc->sc_if.if_bpf) { 876 /* 877 * Save the compressed header, so we 878 * can tack it on later. Note that we 879 * will end up copying garbage in some 880 * cases but this is okay. We remember 881 * where the buffer started so we can 882 * compute the new header length. 883 */ 884 memcpy(chdr, pktstart, CHDR_LEN); 885 } 886 #endif /* NBPFILTER > 0 */ 887 #ifdef INET 888 if ((c = (*pktstart & 0xf0)) != (IPVERSION << 4)) { 889 if (c & 0x80) 890 c = TYPE_COMPRESSED_TCP; 891 else if (c == TYPE_UNCOMPRESSED_TCP) 892 *pktstart &= 0x4f; /* XXX */ 893 /* 894 * We've got something that's not an IP 895 * packet. If compression is enabled, 896 * try to decompress it. Otherwise, if 897 * `auto-enable' compression is on and 898 * it's a reasonable packet, decompress 899 * it and then enable compression. 900 * Otherwise, drop it. 901 */ 902 if (sc->sc_if.if_flags & SC_COMPRESS) { 903 len = sl_uncompress_tcp(&pktstart, len, 904 (u_int)c, &sc->sc_comp); 905 if (len <= 0) { 906 m_freem(m); 907 continue; 908 } 909 } else if ((sc->sc_if.if_flags & SC_AUTOCOMP) && 910 c == TYPE_UNCOMPRESSED_TCP && len >= 40) { 911 len = sl_uncompress_tcp(&pktstart, len, 912 (u_int)c, &sc->sc_comp); 913 if (len <= 0) { 914 m_freem(m); 915 continue; 916 } 917 sc->sc_if.if_flags |= SC_COMPRESS; 918 } else { 919 m_freem(m); 920 continue; 921 } 922 } 923 #endif 924 m->m_data = (void *) pktstart; 925 m->m_pkthdr.len = m->m_len = len; 926 #if NBPFILTER > 0 927 if (sc->sc_if.if_bpf) { 928 bpf_mtap_sl_in(sc->sc_if.if_bpf, chdr, &m); 929 if (m == NULL) 930 continue; 931 } 932 #endif /* NBPFILTER > 0 */ 933 /* 934 * If the packet will fit into a single 935 * header mbuf, copy it into one, to save 936 * memory. 937 */ 938 if (m->m_pkthdr.len < MHLEN) { 939 struct mbuf *n; 940 int pktlen; 941 942 MGETHDR(n, M_DONTWAIT, MT_DATA); 943 pktlen = m->m_pkthdr.len; 944 M_MOVE_PKTHDR(n, m); 945 memcpy(mtod(n, void *), mtod(m, void *), pktlen); 946 n->m_len = m->m_len; 947 m_freem(m); 948 m = n; 949 } 950 951 sc->sc_if.if_ipackets++; 952 getbinuptime(&sc->sc_lastpacket); 953 954 #ifdef INET 955 s = splnet(); 956 if (IF_QFULL(&ipintrq)) { 957 IF_DROP(&ipintrq); 958 sc->sc_if.if_ierrors++; 959 sc->sc_if.if_iqdrops++; 960 m_freem(m); 961 } else { 962 IF_ENQUEUE(&ipintrq, m); 963 schednetisr(NETISR_IP); 964 } 965 splx(s); 966 #endif 967 } 968 } 969 970 /* 971 * Process an ioctl request. 972 */ 973 static int 974 slioctl(struct ifnet *ifp, u_long cmd, void *data) 975 { 976 struct ifaddr *ifa = (struct ifaddr *)data; 977 struct ifreq *ifr = (struct ifreq *)data; 978 int s = splnet(), error = 0; 979 struct sl_softc *sc = ifp->if_softc; 980 struct ppp_stats *psp; 981 struct ppp_comp_stats *pcp; 982 983 switch (cmd) { 984 985 case SIOCSIFADDR: 986 if (ifa->ifa_addr->sa_family == AF_INET) 987 ifp->if_flags |= IFF_UP; 988 else 989 error = EAFNOSUPPORT; 990 break; 991 992 case SIOCSIFDSTADDR: 993 if (ifa->ifa_addr->sa_family != AF_INET) 994 error = EAFNOSUPPORT; 995 break; 996 997 case SIOCSIFMTU: 998 if ((ifr->ifr_mtu < 3) || (ifr->ifr_mtu > SLMAX)) { 999 error = EINVAL; 1000 break; 1001 } 1002 sc->sc_if.if_mtu = ifr->ifr_mtu; 1003 break; 1004 1005 case SIOCGIFMTU: 1006 ifr->ifr_mtu = sc->sc_if.if_mtu; 1007 break; 1008 1009 case SIOCADDMULTI: 1010 case SIOCDELMULTI: 1011 if (ifr == 0) { 1012 error = EAFNOSUPPORT; /* XXX */ 1013 break; 1014 } 1015 switch (ifreq_getaddr(cmd, ifr)->sa_family) { 1016 1017 #ifdef INET 1018 case AF_INET: 1019 break; 1020 #endif 1021 1022 default: 1023 error = EAFNOSUPPORT; 1024 break; 1025 } 1026 break; 1027 1028 case SIOCGPPPSTATS: 1029 psp = &((struct ifpppstatsreq *) data)->stats; 1030 (void)memset(psp, 0, sizeof(*psp)); 1031 psp->p.ppp_ibytes = sc->sc_if.if_ibytes; 1032 psp->p.ppp_ipackets = sc->sc_if.if_ipackets; 1033 psp->p.ppp_ierrors = sc->sc_if.if_ierrors; 1034 psp->p.ppp_obytes = sc->sc_if.if_obytes; 1035 psp->p.ppp_opackets = sc->sc_if.if_opackets; 1036 psp->p.ppp_oerrors = sc->sc_if.if_oerrors; 1037 #ifdef INET 1038 psp->vj.vjs_packets = sc->sc_comp.sls_packets; 1039 psp->vj.vjs_compressed = sc->sc_comp.sls_compressed; 1040 psp->vj.vjs_searches = sc->sc_comp.sls_searches; 1041 psp->vj.vjs_misses = sc->sc_comp.sls_misses; 1042 psp->vj.vjs_uncompressedin = sc->sc_comp.sls_uncompressedin; 1043 psp->vj.vjs_compressedin = sc->sc_comp.sls_compressedin; 1044 psp->vj.vjs_errorin = sc->sc_comp.sls_errorin; 1045 psp->vj.vjs_tossed = sc->sc_comp.sls_tossed; 1046 #endif 1047 break; 1048 1049 case SIOCGPPPCSTATS: 1050 pcp = &((struct ifpppcstatsreq *) data)->stats; 1051 (void)memset(pcp, 0, sizeof(*pcp)); 1052 break; 1053 1054 default: 1055 error = EINVAL; 1056 } 1057 splx(s); 1058 return error; 1059 } 1060