1 /* $NetBSD: if_sl.c,v 1.90 2004/12/06 02:59:23 christos 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 1.90 2004/12/06 02:59:23 christos 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 #endif 83 84 #include <machine/cpu.h> 85 #include <machine/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> 102 103 #if NBPFILTER > 0 104 #include <sys/time.h> 105 #include <net/bpf.h> 106 #endif 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,CBSIZE) 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 */ 173 174 static int sl_clone_create(struct if_clone *, int); 175 static int sl_clone_destroy(struct ifnet *); 176 177 static LIST_HEAD(, sl_softc) sl_softc_list; 178 179 struct 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 */ 186 187 #ifndef __HAVE_GENERIC_SOFT_INTERRUPTS 188 void slnetisr(void); 189 #endif 190 void slintr(void *); 191 192 static int slinit __P((struct sl_softc *)); 193 static struct mbuf *sl_btom __P((struct sl_softc *, int)); 194 195 void 196 slattach(void) 197 { 198 LIST_INIT(&sl_softc_list); 199 if_clone_attach(&sl_cloner); 200 } 201 202 static int 203 sl_clone_create(struct if_clone *ifc, int unit) 204 { 205 struct sl_softc *sc; 206 207 MALLOC(sc, struct sl_softc *, sizeof(*sc), M_DEVBUF, M_WAIT|M_ZERO); 208 sc->sc_unit = unit; 209 (void)snprintf(sc->sc_if.if_xname, sizeof(sc->sc_if.if_xname), 210 "%s%d", ifc->ifc_name, unit); 211 sc->sc_if.if_softc = sc; 212 sc->sc_if.if_mtu = SLMTU; 213 sc->sc_if.if_flags = IFF_POINTOPOINT | SC_AUTOCOMP | IFF_MULTICAST; 214 sc->sc_if.if_type = IFT_SLIP; 215 sc->sc_if.if_ioctl = slioctl; 216 sc->sc_if.if_output = sloutput; 217 sc->sc_if.if_dlt = DLT_SLIP; 218 sc->sc_fastq.ifq_maxlen = 32; 219 IFQ_SET_READY(&sc->sc_if.if_snd); 220 if_attach(&sc->sc_if); 221 if_alloc_sadl(&sc->sc_if); 222 #if NBPFILTER > 0 223 bpfattach(&sc->sc_if, DLT_SLIP, SLIP_HDRLEN); 224 #endif 225 LIST_INSERT_HEAD(&sl_softc_list, sc, sc_iflist); 226 return 0; 227 } 228 229 static int 230 sl_clone_destroy(struct ifnet *ifp) 231 { 232 struct sl_softc *sc = (struct sl_softc *)ifp->if_softc; 233 234 if (sc->sc_ttyp != NULL) 235 return EBUSY; /* Not removing it */ 236 237 LIST_REMOVE(sc, sc_iflist); 238 239 #if NBPFILTER > 0 240 bpfdetach(ifp); 241 #endif 242 if_detach(ifp); 243 244 FREE(sc, M_DEVBUF); 245 return 0; 246 } 247 248 static int 249 slinit(sc) 250 struct sl_softc *sc; 251 { 252 253 if (sc->sc_mbuf == NULL) { 254 sc->sc_mbuf = m_gethdr(M_WAIT, MT_DATA); 255 m_clget(sc->sc_mbuf, M_WAIT); 256 } 257 sc->sc_ep = (u_char *) sc->sc_mbuf->m_ext.ext_buf + 258 sc->sc_mbuf->m_ext.ext_size; 259 sc->sc_mp = sc->sc_pktstart = (u_char *) sc->sc_mbuf->m_ext.ext_buf + 260 BUFOFFSET; 261 262 #ifdef INET 263 sl_compress_init(&sc->sc_comp); 264 #endif 265 266 return (1); 267 } 268 269 /* 270 * Line specific open routine. 271 * Attach the given tty to the first available sl unit. 272 */ 273 /* ARGSUSED */ 274 int 275 slopen(dev, tp) 276 dev_t dev; 277 struct tty *tp; 278 { 279 struct proc *p = curproc; /* XXX */ 280 struct sl_softc *sc; 281 int error; 282 int s; 283 284 if ((error = suser(p->p_ucred, &p->p_acflag)) != 0) 285 return (error); 286 287 if (tp->t_linesw->l_no == SLIPDISC) 288 return (0); 289 290 LIST_FOREACH(sc, &sl_softc_list, sc_iflist) 291 if (sc->sc_ttyp == NULL) { 292 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 293 sc->sc_si = softintr_establish(IPL_SOFTNET, 294 slintr, sc); 295 if (sc->sc_si == NULL) 296 return (ENOMEM); 297 #endif 298 if (slinit(sc) == 0) { 299 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 300 softintr_disestablish(sc->sc_si); 301 #endif 302 return (ENOBUFS); 303 } 304 tp->t_sc = (caddr_t)sc; 305 sc->sc_ttyp = tp; 306 sc->sc_if.if_baudrate = tp->t_ospeed; 307 s = spltty(); 308 tp->t_state |= TS_ISOPEN | TS_XCLUDE; 309 splx(s); 310 ttyflush(tp, FREAD | FWRITE); 311 #ifdef __NetBSD__ 312 /* 313 * make sure tty output queue is large enough 314 * to hold a full-sized packet (including frame 315 * end, and a possible extra frame end). full-sized 316 * packet occupies a max of 2*SLMAX bytes (because 317 * of possible escapes), and add two on for frame 318 * ends. 319 */ 320 s = spltty(); 321 if (tp->t_outq.c_cn < 2*SLMAX+2) { 322 sc->sc_oldbufsize = tp->t_outq.c_cn; 323 sc->sc_oldbufquot = tp->t_outq.c_cq != 0; 324 325 clfree(&tp->t_outq); 326 error = clalloc(&tp->t_outq, 2*SLMAX+2, 0); 327 if (error) { 328 splx(s); 329 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 330 softintr_disestablish(sc->sc_si); 331 #endif 332 /* 333 * clalloc() might return -1 which 334 * is no good, so we need to return 335 * something else. 336 */ 337 return (ENOMEM); /* XXX ?! */ 338 } 339 } else 340 sc->sc_oldbufsize = sc->sc_oldbufquot = 0; 341 splx(s); 342 #endif /* __NetBSD__ */ 343 return (0); 344 } 345 return (ENXIO); 346 } 347 348 /* 349 * Line specific close routine. 350 * Detach the tty from the sl unit. 351 */ 352 void 353 slclose(tp) 354 struct tty *tp; 355 { 356 struct sl_softc *sc; 357 int s; 358 359 ttywflush(tp); 360 sc = tp->t_sc; 361 362 if (sc != NULL) { 363 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 364 softintr_disestablish(sc->sc_si); 365 #endif 366 s = splnet(); 367 if_down(&sc->sc_if); 368 IF_PURGE(&sc->sc_fastq); 369 splx(s); 370 371 s = spltty(); 372 tp->t_linesw = linesw[0]; /* default line disc. */ 373 tp->t_state = 0; 374 375 sc->sc_ttyp = NULL; 376 tp->t_sc = NULL; 377 378 m_freem(sc->sc_mbuf); 379 sc->sc_mbuf = NULL; 380 sc->sc_ep = sc->sc_mp = sc->sc_pktstart = NULL; 381 IF_PURGE(&sc->sc_inq); 382 383 /* 384 * If necessary, install a new outq buffer of the 385 * appropriate size. 386 */ 387 if (sc->sc_oldbufsize != 0) { 388 clfree(&tp->t_outq); 389 clalloc(&tp->t_outq, sc->sc_oldbufsize, 390 sc->sc_oldbufquot); 391 } 392 splx(s); 393 } 394 } 395 396 /* 397 * Line specific (tty) ioctl routine. 398 * Provide a way to get the sl unit number. 399 */ 400 /* ARGSUSED */ 401 int 402 sltioctl(tp, cmd, data, flag) 403 struct tty *tp; 404 u_long cmd; 405 caddr_t data; 406 int flag; 407 { 408 struct sl_softc *sc = (struct sl_softc *)tp->t_sc; 409 410 switch (cmd) { 411 case SLIOCGUNIT: 412 *(int *)data = sc->sc_unit; /* XXX */ 413 break; 414 415 default: 416 return (EPASSTHROUGH); 417 } 418 return (0); 419 } 420 421 /* 422 * Queue a packet. Start transmission if not active. 423 * Compression happens in slintr(); if we do it here, IP TOS 424 * will cause us to not compress "background" packets, because 425 * ordering gets trashed. It can be done for all packets in slintr(). 426 */ 427 int 428 sloutput(ifp, m, dst, rtp) 429 struct ifnet *ifp; 430 struct mbuf *m; 431 struct sockaddr *dst; 432 struct rtentry *rtp; 433 { 434 struct sl_softc *sc = ifp->if_softc; 435 struct ip *ip; 436 int s, error; 437 ALTQ_DECL(struct altq_pktattr pktattr;) 438 439 IFQ_CLASSIFY(&ifp->if_snd, m, dst->sa_family, &pktattr); 440 441 /* 442 * `Cannot happen' (see slioctl). Someday we will extend 443 * the line protocol to support other address families. 444 */ 445 if (dst->sa_family != AF_INET) { 446 printf("%s: af%d not supported\n", sc->sc_if.if_xname, 447 dst->sa_family); 448 m_freem(m); 449 sc->sc_if.if_noproto++; 450 return (EAFNOSUPPORT); 451 } 452 453 if (sc->sc_ttyp == NULL) { 454 m_freem(m); 455 return (ENETDOWN); /* sort of */ 456 } 457 if ((sc->sc_ttyp->t_state & TS_CARR_ON) == 0 && 458 (sc->sc_ttyp->t_cflag & CLOCAL) == 0) { 459 m_freem(m); 460 printf("%s: no carrier and not local\n", sc->sc_if.if_xname); 461 return (EHOSTUNREACH); 462 } 463 ip = mtod(m, struct ip *); 464 #ifdef INET 465 if (sc->sc_if.if_flags & SC_NOICMP && ip->ip_p == IPPROTO_ICMP) { 466 m_freem(m); 467 return (ENETRESET); /* XXX ? */ 468 } 469 #endif 470 471 s = spltty(); 472 if (sc->sc_oqlen && sc->sc_ttyp->t_outq.c_cc == sc->sc_oqlen) { 473 struct timeval tv; 474 475 /* if output's been stalled for too long, and restart */ 476 timersub(&time, &sc->sc_lastpacket, &tv); 477 if (tv.tv_sec > 0) { 478 sc->sc_otimeout++; 479 slstart(sc->sc_ttyp); 480 } 481 } 482 splx(s); 483 484 s = splnet(); 485 #ifdef INET 486 if ((ip->ip_tos & IPTOS_LOWDELAY) != 0 487 #ifdef ALTQ 488 && ALTQ_IS_ENABLED(&ifp->if_snd) == 0 489 #endif 490 ) { 491 if (IF_QFULL(&sc->sc_fastq)) { 492 IF_DROP(&sc->sc_fastq); 493 m_freem(m); 494 error = ENOBUFS; 495 } else { 496 IF_ENQUEUE(&sc->sc_fastq, m); 497 error = 0; 498 } 499 } else 500 #endif 501 IFQ_ENQUEUE(&ifp->if_snd, m, &pktattr, error); 502 if (error) { 503 splx(s); 504 ifp->if_oerrors++; 505 return (error); 506 } 507 sc->sc_lastpacket = time; 508 splx(s); 509 510 s = spltty(); 511 if ((sc->sc_oqlen = sc->sc_ttyp->t_outq.c_cc) == 0) 512 slstart(sc->sc_ttyp); 513 splx(s); 514 515 return (0); 516 } 517 518 /* 519 * Start output on interface. Get another datagram 520 * to send from the interface queue and map it to 521 * the interface before starting output. 522 */ 523 void 524 slstart(tp) 525 struct tty *tp; 526 { 527 struct sl_softc *sc = tp->t_sc; 528 529 /* 530 * If there is more in the output queue, just send it now. 531 * We are being called in lieu of ttstart and must do what 532 * it would. 533 */ 534 if (tp->t_outq.c_cc != 0) { 535 (*tp->t_oproc)(tp); 536 if (tp->t_outq.c_cc > SLIP_HIWAT) 537 return; 538 } 539 540 /* 541 * This happens briefly when the line shuts down. 542 */ 543 if (sc == NULL) 544 return; 545 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 546 softintr_schedule(sc->sc_si); 547 #else 548 { 549 int s = splhigh(); 550 schednetisr(NETISR_SLIP); 551 splx(s); 552 } 553 #endif 554 } 555 556 /* 557 * Copy data buffer to mbuf chain; add ifnet pointer. 558 */ 559 static struct mbuf * 560 sl_btom(sc, len) 561 struct sl_softc *sc; 562 int len; 563 { 564 struct mbuf *m; 565 566 /* 567 * Allocate a new input buffer and swap. 568 */ 569 m = sc->sc_mbuf; 570 MGETHDR(sc->sc_mbuf, M_DONTWAIT, MT_DATA); 571 if (sc->sc_mbuf == NULL) { 572 sc->sc_mbuf = m; 573 return (NULL); 574 } 575 MCLGET(sc->sc_mbuf, M_DONTWAIT); 576 if ((sc->sc_mbuf->m_flags & M_EXT) == 0) { 577 m_freem(sc->sc_mbuf); 578 sc->sc_mbuf = m; 579 return (NULL); 580 } 581 sc->sc_ep = (u_char *) sc->sc_mbuf->m_ext.ext_buf + 582 sc->sc_mbuf->m_ext.ext_size; 583 584 m->m_data = sc->sc_pktstart; 585 586 m->m_pkthdr.len = m->m_len = len; 587 m->m_pkthdr.rcvif = &sc->sc_if; 588 return (m); 589 } 590 591 /* 592 * tty interface receiver interrupt. 593 */ 594 void 595 slinput(c, tp) 596 int c; 597 struct tty *tp; 598 { 599 struct sl_softc *sc; 600 struct mbuf *m; 601 int len; 602 603 tk_nin++; 604 sc = (struct sl_softc *)tp->t_sc; 605 if (sc == NULL) 606 return; 607 if ((c & TTY_ERRORMASK) || ((tp->t_state & TS_CARR_ON) == 0 && 608 (tp->t_cflag & CLOCAL) == 0)) { 609 sc->sc_flags |= SC_ERROR; 610 return; 611 } 612 c &= TTY_CHARMASK; 613 614 ++sc->sc_if.if_ibytes; 615 616 if (sc->sc_if.if_flags & IFF_DEBUG) { 617 if (c == ABT_ESC) { 618 /* 619 * If we have a previous abort, see whether 620 * this one is within the time limit. 621 */ 622 if (sc->sc_abortcount && 623 time.tv_sec >= sc->sc_starttime + ABT_WINDOW) 624 sc->sc_abortcount = 0; 625 /* 626 * If we see an abort after "idle" time, count it; 627 * record when the first abort escape arrived. 628 */ 629 if (time.tv_sec >= sc->sc_lasttime + ABT_IDLE) { 630 if (++sc->sc_abortcount == 1) 631 sc->sc_starttime = time.tv_sec; 632 if (sc->sc_abortcount >= ABT_COUNT) { 633 slclose(tp); 634 return; 635 } 636 } 637 } else 638 sc->sc_abortcount = 0; 639 sc->sc_lasttime = time.tv_sec; 640 } 641 642 switch (c) { 643 644 case TRANS_FRAME_ESCAPE: 645 if (sc->sc_escape) 646 c = FRAME_ESCAPE; 647 break; 648 649 case TRANS_FRAME_END: 650 if (sc->sc_escape) 651 c = FRAME_END; 652 break; 653 654 case FRAME_ESCAPE: 655 sc->sc_escape = 1; 656 return; 657 658 case FRAME_END: 659 if(sc->sc_flags & SC_ERROR) { 660 sc->sc_flags &= ~SC_ERROR; 661 goto newpack; 662 } 663 len = sc->sc_mp - sc->sc_pktstart; 664 if (len < 3) 665 /* less than min length packet - ignore */ 666 goto newpack; 667 668 m = sl_btom(sc, len); 669 if (m == NULL) 670 goto error; 671 672 IF_ENQUEUE(&sc->sc_inq, m); 673 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 674 softintr_schedule(sc->sc_si); 675 #else 676 { 677 int s = splhigh(); 678 schednetisr(NETISR_SLIP); 679 splx(s); 680 } 681 #endif 682 goto newpack; 683 } 684 if (sc->sc_mp < sc->sc_ep) { 685 *sc->sc_mp++ = c; 686 sc->sc_escape = 0; 687 return; 688 } 689 690 /* can't put lower; would miss an extra frame */ 691 sc->sc_flags |= SC_ERROR; 692 693 error: 694 sc->sc_if.if_ierrors++; 695 newpack: 696 sc->sc_mp = sc->sc_pktstart = (u_char *) sc->sc_mbuf->m_ext.ext_buf + 697 BUFOFFSET; 698 sc->sc_escape = 0; 699 } 700 701 #ifndef __HAVE_GENERIC_SOFT_INTERRUPTS 702 void 703 slnetisr(void) 704 { 705 struct sl_softc *sc; 706 707 LIST_FOREACH(sc, &sl_softc_list, sc_iflist) { 708 if (sc->sc_ttyp == NULL) 709 continue; 710 slintr(sc); 711 } 712 } 713 #endif 714 715 void 716 slintr(void *arg) 717 { 718 struct sl_softc *sc = arg; 719 struct tty *tp = sc->sc_ttyp; 720 struct mbuf *m; 721 int s, len; 722 u_char *pktstart; 723 #ifdef INET 724 u_char c; 725 #endif 726 #if NBPFILTER > 0 727 u_char chdr[CHDR_LEN]; 728 #endif 729 730 KASSERT(tp != NULL); 731 732 /* 733 * Output processing loop. 734 */ 735 for (;;) { 736 #ifdef INET 737 struct ip *ip; 738 #endif 739 struct mbuf *m2; 740 #if NBPFILTER > 0 741 struct mbuf *bpf_m; 742 #endif 743 744 /* 745 * Do not remove the packet from the queue if it 746 * doesn't look like it will fit into the current 747 * serial output queue. With a packet full of 748 * escapes, this could be as bad as MTU*2+2. 749 */ 750 s = spltty(); 751 if (tp->t_outq.c_cn - tp->t_outq.c_cc < 752 2*sc->sc_if.if_mtu+2) { 753 splx(s); 754 break; 755 } 756 splx(s); 757 758 /* 759 * Get a packet and send it to the interface. 760 */ 761 s = splnet(); 762 IF_DEQUEUE(&sc->sc_fastq, m); 763 if (m) 764 sc->sc_if.if_omcasts++; /* XXX */ 765 else 766 IFQ_DEQUEUE(&sc->sc_if.if_snd, m); 767 splx(s); 768 769 if (m == NULL) 770 break; 771 772 /* 773 * We do the header compression here rather than in 774 * sloutput() because the packets will be out of order 775 * if we are using TOS queueing, and the connection 776 * ID compression will get munged when this happens. 777 */ 778 #if NBPFILTER > 0 779 if (sc->sc_if.if_bpf) { 780 /* 781 * We need to save the TCP/IP header before 782 * it's compressed. To avoid complicated 783 * code, we just make a deep copy of the 784 * entire packet (since this is a serial 785 * line, packets should be short and/or the 786 * copy should be negligible cost compared 787 * to the packet transmission time). 788 */ 789 bpf_m = m_dup(m, 0, M_COPYALL, M_DONTWAIT); 790 } else 791 bpf_m = NULL; 792 #endif 793 #ifdef INET 794 if ((ip = mtod(m, struct ip *))->ip_p == IPPROTO_TCP) { 795 if (sc->sc_if.if_flags & SC_COMPRESS) 796 *mtod(m, u_char *) |= 797 sl_compress_tcp(m, ip, 798 &sc->sc_comp, 1); 799 } 800 #endif 801 #if NBPFILTER > 0 802 if (sc->sc_if.if_bpf && bpf_m != NULL) 803 bpf_mtap_sl_out(sc->sc_if.if_bpf, mtod(m, u_char *), 804 bpf_m); 805 #endif 806 sc->sc_lastpacket = time; 807 808 s = spltty(); 809 810 /* 811 * The extra FRAME_END will start up a new packet, 812 * and thus will flush any accumulated garbage. We 813 * do this whenever the line may have been idle for 814 * some time. 815 */ 816 if (tp->t_outq.c_cc == 0) { 817 sc->sc_if.if_obytes++; 818 (void) putc(FRAME_END, &tp->t_outq); 819 } 820 821 while (m) { 822 u_char *bp, *cp, *ep; 823 824 bp = cp = mtod(m, u_char *); 825 ep = cp + m->m_len; 826 while (cp < ep) { 827 /* 828 * Find out how many bytes in the 829 * string we can handle without 830 * doing something special. 831 */ 832 while (cp < ep) { 833 switch (*cp++) { 834 case FRAME_ESCAPE: 835 case FRAME_END: 836 cp--; 837 goto out; 838 } 839 } 840 out: 841 if (cp > bp) { 842 /* 843 * Put N characters at once 844 * into the tty output queue. 845 */ 846 if (b_to_q(bp, cp - bp, 847 &tp->t_outq)) 848 break; 849 sc->sc_if.if_obytes += cp - bp; 850 } 851 /* 852 * If there are characters left in 853 * the mbuf, the first one must be 854 * special.. Put it out in a different 855 * form. 856 */ 857 if (cp < ep) { 858 if (putc(FRAME_ESCAPE, 859 &tp->t_outq)) 860 break; 861 if (putc(*cp++ == FRAME_ESCAPE ? 862 TRANS_FRAME_ESCAPE : 863 TRANS_FRAME_END, 864 &tp->t_outq)) { 865 (void) 866 unputc(&tp->t_outq); 867 break; 868 } 869 sc->sc_if.if_obytes += 2; 870 } 871 bp = cp; 872 } 873 MFREE(m, m2); 874 m = m2; 875 } 876 877 if (putc(FRAME_END, &tp->t_outq)) { 878 /* 879 * Not enough room. Remove a char to make 880 * room and end the packet normally. If 881 * you get many collisions (more than one 882 * or two a day), you probably do not have 883 * enough clists and you should increase 884 * "nclist" in param.c 885 */ 886 (void) unputc(&tp->t_outq); 887 (void) putc(FRAME_END, &tp->t_outq); 888 sc->sc_if.if_collisions++; 889 } else { 890 sc->sc_if.if_obytes++; 891 sc->sc_if.if_opackets++; 892 } 893 894 /* 895 * We now have characters in the output queue, 896 * kick the serial port. 897 */ 898 (*tp->t_oproc)(tp); 899 splx(s); 900 } 901 902 /* 903 * Input processing loop. 904 */ 905 for (;;) { 906 s = spltty(); 907 IF_DEQUEUE(&sc->sc_inq, m); 908 splx(s); 909 if (m == NULL) 910 break; 911 pktstart = mtod(m, u_char *); 912 len = m->m_pkthdr.len; 913 #if NBPFILTER > 0 914 if (sc->sc_if.if_bpf) { 915 /* 916 * Save the compressed header, so we 917 * can tack it on later. Note that we 918 * will end up copying garbage in some 919 * cases but this is okay. We remember 920 * where the buffer started so we can 921 * compute the new header length. 922 */ 923 memcpy(chdr, pktstart, CHDR_LEN); 924 } 925 #endif /* NBPFILTER > 0 */ 926 #ifdef INET 927 if ((c = (*pktstart & 0xf0)) != (IPVERSION << 4)) { 928 if (c & 0x80) 929 c = TYPE_COMPRESSED_TCP; 930 else if (c == TYPE_UNCOMPRESSED_TCP) 931 *pktstart &= 0x4f; /* XXX */ 932 /* 933 * We've got something that's not an IP 934 * packet. If compression is enabled, 935 * try to decompress it. Otherwise, if 936 * `auto-enable' compression is on and 937 * it's a reasonable packet, decompress 938 * it and then enable compression. 939 * Otherwise, drop it. 940 */ 941 if (sc->sc_if.if_flags & SC_COMPRESS) { 942 len = sl_uncompress_tcp(&pktstart, len, 943 (u_int)c, &sc->sc_comp); 944 if (len <= 0) { 945 m_freem(m); 946 continue; 947 } 948 } else if ((sc->sc_if.if_flags & SC_AUTOCOMP) && 949 c == TYPE_UNCOMPRESSED_TCP && len >= 40) { 950 len = sl_uncompress_tcp(&pktstart, len, 951 (u_int)c, &sc->sc_comp); 952 if (len <= 0) { 953 m_freem(m); 954 continue; 955 } 956 sc->sc_if.if_flags |= SC_COMPRESS; 957 } else { 958 m_freem(m); 959 continue; 960 } 961 } 962 #endif 963 m->m_data = (caddr_t) pktstart; 964 m->m_pkthdr.len = m->m_len = len; 965 #if NBPFILTER > 0 966 if (sc->sc_if.if_bpf) { 967 bpf_mtap_sl_in(sc->sc_if.if_bpf, chdr, &m); 968 if (m == NULL) 969 continue; 970 } 971 #endif /* NBPFILTER > 0 */ 972 /* 973 * If the packet will fit into a single 974 * header mbuf, copy it into one, to save 975 * memory. 976 */ 977 if (m->m_pkthdr.len < MHLEN) { 978 struct mbuf *n; 979 980 MGETHDR(n, M_DONTWAIT, MT_DATA); 981 M_COPY_PKTHDR(n, m); 982 memcpy(mtod(n, caddr_t), mtod(m, caddr_t), 983 m->m_pkthdr.len); 984 n->m_len = m->m_len; 985 m_freem(m); 986 m = n; 987 } 988 989 sc->sc_if.if_ipackets++; 990 sc->sc_lastpacket = time; 991 992 #ifdef INET 993 s = splnet(); 994 if (IF_QFULL(&ipintrq)) { 995 IF_DROP(&ipintrq); 996 sc->sc_if.if_ierrors++; 997 sc->sc_if.if_iqdrops++; 998 m_freem(m); 999 } else { 1000 IF_ENQUEUE(&ipintrq, m); 1001 schednetisr(NETISR_IP); 1002 } 1003 splx(s); 1004 #endif 1005 } 1006 } 1007 1008 /* 1009 * Process an ioctl request. 1010 */ 1011 int 1012 slioctl(ifp, cmd, data) 1013 struct ifnet *ifp; 1014 u_long cmd; 1015 caddr_t data; 1016 { 1017 struct ifaddr *ifa = (struct ifaddr *)data; 1018 struct ifreq *ifr = (struct ifreq *)data; 1019 int s = splnet(), error = 0; 1020 struct sl_softc *sc = ifp->if_softc; 1021 1022 switch (cmd) { 1023 1024 case SIOCSIFADDR: 1025 if (ifa->ifa_addr->sa_family == AF_INET) 1026 ifp->if_flags |= IFF_UP; 1027 else 1028 error = EAFNOSUPPORT; 1029 break; 1030 1031 case SIOCSIFDSTADDR: 1032 if (ifa->ifa_addr->sa_family != AF_INET) 1033 error = EAFNOSUPPORT; 1034 break; 1035 1036 case SIOCSIFMTU: 1037 if ((ifr->ifr_mtu < 3) || (ifr->ifr_mtu > SLMAX)) { 1038 error = EINVAL; 1039 break; 1040 } 1041 sc->sc_if.if_mtu = ifr->ifr_mtu; 1042 break; 1043 1044 case SIOCGIFMTU: 1045 ifr->ifr_mtu = sc->sc_if.if_mtu; 1046 break; 1047 1048 case SIOCADDMULTI: 1049 case SIOCDELMULTI: 1050 if (ifr == 0) { 1051 error = EAFNOSUPPORT; /* XXX */ 1052 break; 1053 } 1054 switch (ifr->ifr_addr.sa_family) { 1055 1056 #ifdef INET 1057 case AF_INET: 1058 break; 1059 #endif 1060 1061 default: 1062 error = EAFNOSUPPORT; 1063 break; 1064 } 1065 break; 1066 1067 default: 1068 error = EINVAL; 1069 } 1070 splx(s); 1071 return (error); 1072 } 1073