1 /* $NetBSD: if_sl.c,v 1.86 2004/08/19 20:58:24 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 1.86 2004/08/19 20:58:24 christos Exp $"); 64 65 #include "sl.h" 66 #if NSL > 0 67 68 #include "opt_inet.h" 69 #include "bpfilter.h" 70 71 #include <sys/param.h> 72 #include <sys/proc.h> 73 #include <sys/malloc.h> 74 #include <sys/mbuf.h> 75 #include <sys/buf.h> 76 #include <sys/dkstat.h> 77 #include <sys/socket.h> 78 #include <sys/ioctl.h> 79 #include <sys/file.h> 80 #include <sys/conf.h> 81 #include <sys/tty.h> 82 #include <sys/kernel.h> 83 #if __NetBSD__ 84 #include <sys/systm.h> 85 #endif 86 87 #include <machine/cpu.h> 88 #include <machine/intr.h> 89 90 #include <net/if.h> 91 #include <net/if_types.h> 92 #include <net/netisr.h> 93 #include <net/route.h> 94 95 #ifdef INET 96 #include <netinet/in.h> 97 #include <netinet/in_systm.h> 98 #include <netinet/in_var.h> 99 #include <netinet/ip.h> 100 #else 101 #error Slip without inet? 102 #endif 103 104 #include <net/slcompress.h> 105 #include <net/if_slvar.h> 106 #include <net/slip.h> 107 108 #if NBPFILTER > 0 109 #include <sys/time.h> 110 #include <net/bpf.h> 111 #endif 112 113 /* 114 * SLMAX is a hard limit on input packet size. To simplify the code 115 * and improve performance, we require that packets fit in an mbuf 116 * cluster, and if we get a compressed packet, there's enough extra 117 * room to expand the header into a max length tcp/ip header (128 118 * bytes). So, SLMAX can be at most 119 * MCLBYTES - 128 120 * 121 * SLMTU is a hard limit on output packet size. To insure good 122 * interactive response, SLMTU wants to be the smallest size that 123 * amortizes the header cost. (Remember that even with 124 * type-of-service queuing, we have to wait for any in-progress 125 * packet to finish. I.e., we wait, on the average, 1/2 * mtu / 126 * cps, where cps is the line speed in characters per second. 127 * E.g., 533ms wait for a 1024 byte MTU on a 9600 baud line. The 128 * average compressed header size is 6-8 bytes so any MTU > 90 129 * bytes will give us 90% of the line bandwidth. A 100ms wait is 130 * tolerable (500ms is not), so want an MTU around 296. (Since TCP 131 * will send 256 byte segments (to allow for 40 byte headers), the 132 * typical packet size on the wire will be around 260 bytes). In 133 * 4.3tahoe+ systems, we can set an MTU in a route so we do that & 134 * leave the interface MTU relatively high (so we don't IP fragment 135 * when acting as a gateway to someone using a stupid MTU). 136 * 137 * Similar considerations apply to SLIP_HIWAT: It's the amount of 138 * data that will be queued 'downstream' of us (i.e., in clists 139 * waiting to be picked up by the tty output interrupt). If we 140 * queue a lot of data downstream, it's immune to our t.o.s. queuing. 141 * E.g., if SLIP_HIWAT is 1024, the interactive traffic in mixed 142 * telnet/ftp will see a 1 sec wait, independent of the mtu (the 143 * wait is dependent on the ftp window size but that's typically 144 * 1k - 4k). So, we want SLIP_HIWAT just big enough to amortize 145 * the cost (in idle time on the wire) of the tty driver running 146 * off the end of its clists & having to call back slstart for a 147 * new packet. For a tty interface with any buffering at all, this 148 * cost will be zero. Even with a totally brain dead interface (like 149 * the one on a typical workstation), the cost will be <= 1 character 150 * time. So, setting SLIP_HIWAT to ~100 guarantees that we'll lose 151 * at most 1% while maintaining good interactive response. 152 */ 153 #define BUFOFFSET (128+sizeof(struct ifnet **)+SLIP_HDRLEN) 154 #define SLMAX (MCLBYTES - BUFOFFSET) 155 #define SLBUFSIZE (SLMAX + BUFOFFSET) 156 #ifndef SLMTU 157 #define SLMTU 296 158 #endif 159 #if (SLMTU < 3) 160 #error SLMTU way too small. 161 #endif 162 #define SLIP_HIWAT roundup(50,CBSIZE) 163 #ifndef __NetBSD__ /* XXX - cgd */ 164 #define CLISTRESERVE 1024 /* Can't let clists get too low */ 165 #endif /* !__NetBSD__ */ 166 167 /* 168 * SLIP ABORT ESCAPE MECHANISM: 169 * (inspired by HAYES modem escape arrangement) 170 * 1sec escape 1sec escape 1sec escape { 1sec escape 1sec escape } 171 * within window time signals a "soft" exit from slip mode by remote end 172 * if the IFF_DEBUG flag is on. 173 */ 174 #define ABT_ESC '\033' /* can't be t_intr - distant host must know it*/ 175 #define ABT_IDLE 1 /* in seconds - idle before an escape */ 176 #define ABT_COUNT 3 /* count of escapes for abort */ 177 #define ABT_WINDOW (ABT_COUNT*2+2) /* in seconds - time to count */ 178 179 struct sl_softc sl_softc[NSL]; 180 181 #define FRAME_END 0xc0 /* Frame End */ 182 #define FRAME_ESCAPE 0xdb /* Frame Esc */ 183 #define TRANS_FRAME_END 0xdc /* transposed frame end */ 184 #define TRANS_FRAME_ESCAPE 0xdd /* transposed frame esc */ 185 186 #ifndef __HAVE_GENERIC_SOFT_INTERRUPTS 187 void slnetisr(void); 188 #endif 189 void slintr(void *); 190 191 static int slinit __P((struct sl_softc *)); 192 static struct mbuf *sl_btom __P((struct sl_softc *, int)); 193 194 /* 195 * Called from boot code to establish sl interfaces. 196 */ 197 void 198 slattach() 199 { 200 struct sl_softc *sc; 201 int i = 0; 202 203 for (sc = sl_softc; i < NSL; sc++) { 204 sc->sc_unit = i; /* XXX */ 205 snprintf(sc->sc_if.if_xname, sizeof(sc->sc_if.if_xname), 206 "sl%d", i++); 207 sc->sc_if.if_softc = sc; 208 sc->sc_if.if_mtu = SLMTU; 209 sc->sc_if.if_flags = 210 IFF_POINTOPOINT | SC_AUTOCOMP | IFF_MULTICAST; 211 sc->sc_if.if_type = IFT_SLIP; 212 sc->sc_if.if_ioctl = slioctl; 213 sc->sc_if.if_output = sloutput; 214 sc->sc_if.if_dlt = DLT_SLIP; 215 sc->sc_fastq.ifq_maxlen = 32; 216 IFQ_SET_READY(&sc->sc_if.if_snd); 217 if_attach(&sc->sc_if); 218 if_alloc_sadl(&sc->sc_if); 219 #if NBPFILTER > 0 220 bpfattach(&sc->sc_if, DLT_SLIP, SLIP_HDRLEN); 221 #endif 222 } 223 } 224 225 static int 226 slinit(sc) 227 struct sl_softc *sc; 228 { 229 230 if (sc->sc_mbuf == NULL) { 231 sc->sc_mbuf = m_gethdr(M_WAIT, MT_DATA); 232 m_clget(sc->sc_mbuf, M_WAIT); 233 } 234 sc->sc_ep = (u_char *) sc->sc_mbuf->m_ext.ext_buf + 235 sc->sc_mbuf->m_ext.ext_size; 236 sc->sc_mp = sc->sc_pktstart = (u_char *) sc->sc_mbuf->m_ext.ext_buf + 237 BUFOFFSET; 238 239 sl_compress_init(&sc->sc_comp); 240 241 return (1); 242 } 243 244 /* 245 * Line specific open routine. 246 * Attach the given tty to the first available sl unit. 247 */ 248 /* ARGSUSED */ 249 int 250 slopen(dev, tp) 251 dev_t dev; 252 struct tty *tp; 253 { 254 struct proc *p = curproc; /* XXX */ 255 struct sl_softc *sc; 256 int nsl; 257 int error; 258 int s; 259 260 if ((error = suser(p->p_ucred, &p->p_acflag)) != 0) 261 return (error); 262 263 if (tp->t_linesw->l_no == SLIPDISC) 264 return (0); 265 266 for (nsl = NSL, sc = sl_softc; --nsl >= 0; sc++) 267 if (sc->sc_ttyp == NULL) { 268 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 269 sc->sc_si = softintr_establish(IPL_SOFTNET, 270 slintr, sc); 271 if (sc->sc_si == NULL) 272 return (ENOMEM); 273 #endif 274 if (slinit(sc) == 0) { 275 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 276 softintr_disestablish(sc->sc_si); 277 #endif 278 return (ENOBUFS); 279 } 280 tp->t_sc = (caddr_t)sc; 281 sc->sc_ttyp = tp; 282 sc->sc_if.if_baudrate = tp->t_ospeed; 283 s = spltty(); 284 tp->t_state |= TS_ISOPEN | TS_XCLUDE; 285 splx(s); 286 ttyflush(tp, FREAD | FWRITE); 287 #ifdef __NetBSD__ 288 /* 289 * make sure tty output queue is large enough 290 * to hold a full-sized packet (including frame 291 * end, and a possible extra frame end). full-sized 292 * packet occupies a max of 2*SLMAX bytes (because 293 * of possible escapes), and add two on for frame 294 * ends. 295 */ 296 s = spltty(); 297 if (tp->t_outq.c_cn < 2*SLMAX+2) { 298 sc->sc_oldbufsize = tp->t_outq.c_cn; 299 sc->sc_oldbufquot = tp->t_outq.c_cq != 0; 300 301 clfree(&tp->t_outq); 302 error = clalloc(&tp->t_outq, 2*SLMAX+2, 0); 303 if (error) { 304 splx(s); 305 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 306 softintr_disestablish(sc->sc_si); 307 #endif 308 /* 309 * clalloc() might return -1 which 310 * is no good, so we need to return 311 * something else. 312 */ 313 return (ENOMEM); /* XXX ?! */ 314 } 315 } else 316 sc->sc_oldbufsize = sc->sc_oldbufquot = 0; 317 splx(s); 318 #endif /* __NetBSD__ */ 319 return (0); 320 } 321 return (ENXIO); 322 } 323 324 /* 325 * Line specific close routine. 326 * Detach the tty from the sl unit. 327 */ 328 void 329 slclose(tp) 330 struct tty *tp; 331 { 332 struct sl_softc *sc; 333 int s; 334 335 ttywflush(tp); 336 sc = tp->t_sc; 337 338 if (sc != NULL) { 339 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 340 softintr_disestablish(sc->sc_si); 341 #endif 342 s = splnet(); 343 if_down(&sc->sc_if); 344 IF_PURGE(&sc->sc_fastq); 345 splx(s); 346 347 s = spltty(); 348 tp->t_linesw = linesw[0]; /* default line disc. */ 349 tp->t_state = 0; 350 351 sc->sc_ttyp = NULL; 352 tp->t_sc = NULL; 353 354 m_freem(sc->sc_mbuf); 355 sc->sc_mbuf = NULL; 356 sc->sc_ep = sc->sc_mp = sc->sc_pktstart = NULL; 357 IF_PURGE(&sc->sc_inq); 358 359 /* 360 * If necessary, install a new outq buffer of the 361 * appropriate size. 362 */ 363 if (sc->sc_oldbufsize != 0) { 364 clfree(&tp->t_outq); 365 clalloc(&tp->t_outq, sc->sc_oldbufsize, 366 sc->sc_oldbufquot); 367 } 368 splx(s); 369 } 370 } 371 372 /* 373 * Line specific (tty) ioctl routine. 374 * Provide a way to get the sl unit number. 375 */ 376 /* ARGSUSED */ 377 int 378 sltioctl(tp, cmd, data, flag) 379 struct tty *tp; 380 u_long cmd; 381 caddr_t data; 382 int flag; 383 { 384 struct sl_softc *sc = (struct sl_softc *)tp->t_sc; 385 386 switch (cmd) { 387 case SLIOCGUNIT: 388 *(int *)data = sc->sc_unit; /* XXX */ 389 break; 390 391 default: 392 return (EPASSTHROUGH); 393 } 394 return (0); 395 } 396 397 /* 398 * Queue a packet. Start transmission if not active. 399 * Compression happens in slintr(); if we do it here, IP TOS 400 * will cause us to not compress "background" packets, because 401 * ordering gets trashed. It can be done for all packets in slintr(). 402 */ 403 int 404 sloutput(ifp, m, dst, rtp) 405 struct ifnet *ifp; 406 struct mbuf *m; 407 struct sockaddr *dst; 408 struct rtentry *rtp; 409 { 410 struct sl_softc *sc = ifp->if_softc; 411 struct ip *ip; 412 int s, error; 413 ALTQ_DECL(struct altq_pktattr pktattr;) 414 415 IFQ_CLASSIFY(&ifp->if_snd, m, dst->sa_family, &pktattr); 416 417 /* 418 * `Cannot happen' (see slioctl). Someday we will extend 419 * the line protocol to support other address families. 420 */ 421 if (dst->sa_family != AF_INET) { 422 printf("%s: af%d not supported\n", sc->sc_if.if_xname, 423 dst->sa_family); 424 m_freem(m); 425 sc->sc_if.if_noproto++; 426 return (EAFNOSUPPORT); 427 } 428 429 if (sc->sc_ttyp == NULL) { 430 m_freem(m); 431 return (ENETDOWN); /* sort of */ 432 } 433 if ((sc->sc_ttyp->t_state & TS_CARR_ON) == 0 && 434 (sc->sc_ttyp->t_cflag & CLOCAL) == 0) { 435 m_freem(m); 436 printf("%s: no carrier and not local\n", sc->sc_if.if_xname); 437 return (EHOSTUNREACH); 438 } 439 ip = mtod(m, struct ip *); 440 if (sc->sc_if.if_flags & SC_NOICMP && ip->ip_p == IPPROTO_ICMP) { 441 m_freem(m); 442 return (ENETRESET); /* XXX ? */ 443 } 444 445 s = spltty(); 446 if (sc->sc_oqlen && sc->sc_ttyp->t_outq.c_cc == sc->sc_oqlen) { 447 struct timeval tv; 448 449 /* if output's been stalled for too long, and restart */ 450 timersub(&time, &sc->sc_lastpacket, &tv); 451 if (tv.tv_sec > 0) { 452 sc->sc_otimeout++; 453 slstart(sc->sc_ttyp); 454 } 455 } 456 splx(s); 457 458 s = splnet(); 459 if ((ip->ip_tos & IPTOS_LOWDELAY) != 0 460 #ifdef ALTQ 461 && ALTQ_IS_ENABLED(&ifp->if_snd) == 0 462 #endif 463 ) { 464 if (IF_QFULL(&sc->sc_fastq)) { 465 IF_DROP(&sc->sc_fastq); 466 m_freem(m); 467 error = ENOBUFS; 468 } else { 469 IF_ENQUEUE(&sc->sc_fastq, m); 470 error = 0; 471 } 472 } else 473 IFQ_ENQUEUE(&ifp->if_snd, m, &pktattr, error); 474 if (error) { 475 splx(s); 476 ifp->if_oerrors++; 477 return (error); 478 } 479 sc->sc_lastpacket = time; 480 splx(s); 481 482 s = spltty(); 483 if ((sc->sc_oqlen = sc->sc_ttyp->t_outq.c_cc) == 0) 484 slstart(sc->sc_ttyp); 485 splx(s); 486 487 return (0); 488 } 489 490 /* 491 * Start output on interface. Get another datagram 492 * to send from the interface queue and map it to 493 * the interface before starting output. 494 */ 495 void 496 slstart(tp) 497 struct tty *tp; 498 { 499 struct sl_softc *sc = tp->t_sc; 500 501 /* 502 * If there is more in the output queue, just send it now. 503 * We are being called in lieu of ttstart and must do what 504 * it would. 505 */ 506 if (tp->t_outq.c_cc != 0) { 507 (*tp->t_oproc)(tp); 508 if (tp->t_outq.c_cc > SLIP_HIWAT) 509 return; 510 } 511 512 /* 513 * This happens briefly when the line shuts down. 514 */ 515 if (sc == NULL) 516 return; 517 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 518 softintr_schedule(sc->sc_si); 519 #else 520 { 521 int s = splhigh(); 522 schednetisr(NETISR_SLIP); 523 splx(s); 524 } 525 #endif 526 } 527 528 /* 529 * Copy data buffer to mbuf chain; add ifnet pointer. 530 */ 531 static struct mbuf * 532 sl_btom(sc, len) 533 struct sl_softc *sc; 534 int len; 535 { 536 struct mbuf *m; 537 538 /* 539 * Allocate a new input buffer and swap. 540 */ 541 m = sc->sc_mbuf; 542 MGETHDR(sc->sc_mbuf, M_DONTWAIT, MT_DATA); 543 if (sc->sc_mbuf == NULL) { 544 sc->sc_mbuf = m; 545 return (NULL); 546 } 547 MCLGET(sc->sc_mbuf, M_DONTWAIT); 548 if ((sc->sc_mbuf->m_flags & M_EXT) == 0) { 549 m_freem(sc->sc_mbuf); 550 sc->sc_mbuf = m; 551 return (NULL); 552 } 553 sc->sc_ep = (u_char *) sc->sc_mbuf->m_ext.ext_buf + 554 sc->sc_mbuf->m_ext.ext_size; 555 556 m->m_data = sc->sc_pktstart; 557 558 m->m_pkthdr.len = m->m_len = len; 559 m->m_pkthdr.rcvif = &sc->sc_if; 560 return (m); 561 } 562 563 /* 564 * tty interface receiver interrupt. 565 */ 566 void 567 slinput(c, tp) 568 int c; 569 struct tty *tp; 570 { 571 struct sl_softc *sc; 572 struct mbuf *m; 573 int len; 574 575 tk_nin++; 576 sc = (struct sl_softc *)tp->t_sc; 577 if (sc == NULL) 578 return; 579 if ((c & TTY_ERRORMASK) || ((tp->t_state & TS_CARR_ON) == 0 && 580 (tp->t_cflag & CLOCAL) == 0)) { 581 sc->sc_flags |= SC_ERROR; 582 return; 583 } 584 c &= TTY_CHARMASK; 585 586 ++sc->sc_if.if_ibytes; 587 588 if (sc->sc_if.if_flags & IFF_DEBUG) { 589 if (c == ABT_ESC) { 590 /* 591 * If we have a previous abort, see whether 592 * this one is within the time limit. 593 */ 594 if (sc->sc_abortcount && 595 time.tv_sec >= sc->sc_starttime + ABT_WINDOW) 596 sc->sc_abortcount = 0; 597 /* 598 * If we see an abort after "idle" time, count it; 599 * record when the first abort escape arrived. 600 */ 601 if (time.tv_sec >= sc->sc_lasttime + ABT_IDLE) { 602 if (++sc->sc_abortcount == 1) 603 sc->sc_starttime = time.tv_sec; 604 if (sc->sc_abortcount >= ABT_COUNT) { 605 slclose(tp); 606 return; 607 } 608 } 609 } else 610 sc->sc_abortcount = 0; 611 sc->sc_lasttime = time.tv_sec; 612 } 613 614 switch (c) { 615 616 case TRANS_FRAME_ESCAPE: 617 if (sc->sc_escape) 618 c = FRAME_ESCAPE; 619 break; 620 621 case TRANS_FRAME_END: 622 if (sc->sc_escape) 623 c = FRAME_END; 624 break; 625 626 case FRAME_ESCAPE: 627 sc->sc_escape = 1; 628 return; 629 630 case FRAME_END: 631 if(sc->sc_flags & SC_ERROR) { 632 sc->sc_flags &= ~SC_ERROR; 633 goto newpack; 634 } 635 len = sc->sc_mp - sc->sc_pktstart; 636 if (len < 3) 637 /* less than min length packet - ignore */ 638 goto newpack; 639 640 m = sl_btom(sc, len); 641 if (m == NULL) 642 goto error; 643 644 IF_ENQUEUE(&sc->sc_inq, m); 645 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 646 softintr_schedule(sc->sc_si); 647 #else 648 { 649 int s = splhigh(); 650 schednetisr(NETISR_SLIP); 651 splx(s); 652 } 653 #endif 654 goto newpack; 655 } 656 if (sc->sc_mp < sc->sc_ep) { 657 *sc->sc_mp++ = c; 658 sc->sc_escape = 0; 659 return; 660 } 661 662 /* can't put lower; would miss an extra frame */ 663 sc->sc_flags |= SC_ERROR; 664 665 error: 666 sc->sc_if.if_ierrors++; 667 newpack: 668 sc->sc_mp = sc->sc_pktstart = (u_char *) sc->sc_mbuf->m_ext.ext_buf + 669 BUFOFFSET; 670 sc->sc_escape = 0; 671 } 672 673 #ifndef __HAVE_GENERIC_SOFT_INTERRUPTS 674 void 675 slnetisr(void) 676 { 677 struct sl_softc *sc; 678 int i; 679 680 for (i = 0; i < NSL; i++) { 681 sc = &sl_softc[i]; 682 if (sc->sc_ttyp == NULL) 683 continue; 684 slintr(sc); 685 } 686 } 687 #endif 688 689 void 690 slintr(void *arg) 691 { 692 struct sl_softc *sc = arg; 693 struct tty *tp = sc->sc_ttyp; 694 struct mbuf *m; 695 int s, len; 696 u_char *pktstart, c; 697 #if NBPFILTER > 0 698 u_char chdr[CHDR_LEN]; 699 #endif 700 701 KASSERT(tp != NULL); 702 703 /* 704 * Output processing loop. 705 */ 706 for (;;) { 707 struct ip *ip; 708 struct mbuf *m2; 709 #if NBPFILTER > 0 710 struct mbuf *bpf_m; 711 #endif 712 713 /* 714 * Do not remove the packet from the queue if it 715 * doesn't look like it will fit into the current 716 * serial output queue. With a packet full of 717 * escapes, this could be as bad as MTU*2+2. 718 */ 719 s = spltty(); 720 if (tp->t_outq.c_cn - tp->t_outq.c_cc < 721 2*sc->sc_if.if_mtu+2) { 722 splx(s); 723 break; 724 } 725 splx(s); 726 727 /* 728 * Get a packet and send it to the interface. 729 */ 730 s = splnet(); 731 IF_DEQUEUE(&sc->sc_fastq, m); 732 if (m) 733 sc->sc_if.if_omcasts++; /* XXX */ 734 else 735 IFQ_DEQUEUE(&sc->sc_if.if_snd, m); 736 splx(s); 737 738 if (m == NULL) 739 break; 740 741 /* 742 * We do the header compression here rather than in 743 * sloutput() because the packets will be out of order 744 * if we are using TOS queueing, and the connection 745 * ID compression will get munged when this happens. 746 */ 747 #if NBPFILTER > 0 748 if (sc->sc_if.if_bpf) { 749 /* 750 * We need to save the TCP/IP header before 751 * it's compressed. To avoid complicated 752 * code, we just make a deep copy of the 753 * entire packet (since this is a serial 754 * line, packets should be short and/or the 755 * copy should be negligible cost compared 756 * to the packet transmission time). 757 */ 758 bpf_m = m_dup(m, 0, M_COPYALL, M_DONTWAIT); 759 } else 760 bpf_m = NULL; 761 #endif 762 if ((ip = mtod(m, struct ip *))->ip_p == IPPROTO_TCP) { 763 if (sc->sc_if.if_flags & SC_COMPRESS) 764 *mtod(m, u_char *) |= 765 sl_compress_tcp(m, ip, 766 &sc->sc_comp, 1); 767 } 768 #if NBPFILTER > 0 769 if (sc->sc_if.if_bpf && bpf_m != NULL) 770 bpf_mtap_sl_out(sc->sc_if.if_bpf, mtod(m, u_char *), 771 bpf_m); 772 #endif 773 sc->sc_lastpacket = time; 774 775 s = spltty(); 776 777 /* 778 * The extra FRAME_END will start up a new packet, 779 * and thus will flush any accumulated garbage. We 780 * do this whenever the line may have been idle for 781 * some time. 782 */ 783 if (tp->t_outq.c_cc == 0) { 784 sc->sc_if.if_obytes++; 785 (void) putc(FRAME_END, &tp->t_outq); 786 } 787 788 while (m) { 789 u_char *bp, *cp, *ep; 790 791 bp = cp = mtod(m, u_char *); 792 ep = cp + m->m_len; 793 while (cp < ep) { 794 /* 795 * Find out how many bytes in the 796 * string we can handle without 797 * doing something special. 798 */ 799 while (cp < ep) { 800 switch (*cp++) { 801 case FRAME_ESCAPE: 802 case FRAME_END: 803 cp--; 804 goto out; 805 } 806 } 807 out: 808 if (cp > bp) { 809 /* 810 * Put N characters at once 811 * into the tty output queue. 812 */ 813 if (b_to_q(bp, cp - bp, 814 &tp->t_outq)) 815 break; 816 sc->sc_if.if_obytes += cp - bp; 817 } 818 /* 819 * If there are characters left in 820 * the mbuf, the first one must be 821 * special.. Put it out in a different 822 * form. 823 */ 824 if (cp < ep) { 825 if (putc(FRAME_ESCAPE, 826 &tp->t_outq)) 827 break; 828 if (putc(*cp++ == FRAME_ESCAPE ? 829 TRANS_FRAME_ESCAPE : 830 TRANS_FRAME_END, 831 &tp->t_outq)) { 832 (void) 833 unputc(&tp->t_outq); 834 break; 835 } 836 sc->sc_if.if_obytes += 2; 837 } 838 bp = cp; 839 } 840 MFREE(m, m2); 841 m = m2; 842 } 843 844 if (putc(FRAME_END, &tp->t_outq)) { 845 /* 846 * Not enough room. Remove a char to make 847 * room and end the packet normally. If 848 * you get many collisions (more than one 849 * or two a day), you probably do not have 850 * enough clists and you should increase 851 * "nclist" in param.c 852 */ 853 (void) unputc(&tp->t_outq); 854 (void) putc(FRAME_END, &tp->t_outq); 855 sc->sc_if.if_collisions++; 856 } else { 857 sc->sc_if.if_obytes++; 858 sc->sc_if.if_opackets++; 859 } 860 861 /* 862 * We now have characters in the output queue, 863 * kick the serial port. 864 */ 865 (*tp->t_oproc)(tp); 866 splx(s); 867 } 868 869 /* 870 * Input processing loop. 871 */ 872 for (;;) { 873 s = spltty(); 874 IF_DEQUEUE(&sc->sc_inq, m); 875 splx(s); 876 if (m == NULL) 877 break; 878 pktstart = mtod(m, u_char *); 879 len = m->m_pkthdr.len; 880 #if NBPFILTER > 0 881 if (sc->sc_if.if_bpf) { 882 /* 883 * Save the compressed header, so we 884 * can tack it on later. Note that we 885 * will end up copying garbage in some 886 * cases but this is okay. We remember 887 * where the buffer started so we can 888 * compute the new header length. 889 */ 890 memcpy(chdr, pktstart, CHDR_LEN); 891 } 892 #endif /* NBPFILTER > 0 */ 893 if ((c = (*pktstart & 0xf0)) != (IPVERSION << 4)) { 894 if (c & 0x80) 895 c = TYPE_COMPRESSED_TCP; 896 else if (c == TYPE_UNCOMPRESSED_TCP) 897 *pktstart &= 0x4f; /* XXX */ 898 /* 899 * We've got something that's not an IP 900 * packet. If compression is enabled, 901 * try to decompress it. Otherwise, if 902 * `auto-enable' compression is on and 903 * it's a reasonable packet, decompress 904 * it and then enable compression. 905 * Otherwise, drop it. 906 */ 907 if (sc->sc_if.if_flags & SC_COMPRESS) { 908 len = sl_uncompress_tcp(&pktstart, len, 909 (u_int)c, &sc->sc_comp); 910 if (len <= 0) { 911 m_freem(m); 912 continue; 913 } 914 } else if ((sc->sc_if.if_flags & SC_AUTOCOMP) && 915 c == TYPE_UNCOMPRESSED_TCP && len >= 40) { 916 len = sl_uncompress_tcp(&pktstart, len, 917 (u_int)c, &sc->sc_comp); 918 if (len <= 0) { 919 m_freem(m); 920 continue; 921 } 922 sc->sc_if.if_flags |= SC_COMPRESS; 923 } else { 924 m_freem(m); 925 continue; 926 } 927 } 928 m->m_data = (caddr_t) pktstart; 929 m->m_pkthdr.len = m->m_len = len; 930 #if NBPFILTER > 0 931 if (sc->sc_if.if_bpf) { 932 bpf_mtap_sl_in(sc->sc_if.if_bpf, chdr, &m); 933 if (m == NULL) 934 continue; 935 } 936 #endif /* NBPFILTER > 0 */ 937 /* 938 * If the packet will fit into a single 939 * header mbuf, copy it into one, to save 940 * memory. 941 */ 942 if (m->m_pkthdr.len < MHLEN) { 943 struct mbuf *n; 944 945 MGETHDR(n, M_DONTWAIT, MT_DATA); 946 M_COPY_PKTHDR(n, m); 947 memcpy(mtod(n, caddr_t), mtod(m, caddr_t), 948 m->m_pkthdr.len); 949 n->m_len = m->m_len; 950 m_freem(m); 951 m = n; 952 } 953 954 sc->sc_if.if_ipackets++; 955 sc->sc_lastpacket = time; 956 957 s = splnet(); 958 if (IF_QFULL(&ipintrq)) { 959 IF_DROP(&ipintrq); 960 sc->sc_if.if_ierrors++; 961 sc->sc_if.if_iqdrops++; 962 m_freem(m); 963 } else { 964 IF_ENQUEUE(&ipintrq, m); 965 schednetisr(NETISR_IP); 966 } 967 splx(s); 968 } 969 } 970 971 /* 972 * Process an ioctl request. 973 */ 974 int 975 slioctl(ifp, cmd, data) 976 struct ifnet *ifp; 977 u_long cmd; 978 caddr_t data; 979 { 980 struct ifaddr *ifa = (struct ifaddr *)data; 981 struct ifreq *ifr = (struct ifreq *)data; 982 int s = splnet(), error = 0; 983 struct sl_softc *sc = ifp->if_softc; 984 985 switch (cmd) { 986 987 case SIOCSIFADDR: 988 if (ifa->ifa_addr->sa_family == AF_INET) 989 ifp->if_flags |= IFF_UP; 990 else 991 error = EAFNOSUPPORT; 992 break; 993 994 case SIOCSIFDSTADDR: 995 if (ifa->ifa_addr->sa_family != AF_INET) 996 error = EAFNOSUPPORT; 997 break; 998 999 case SIOCSIFMTU: 1000 if ((ifr->ifr_mtu < 3) || (ifr->ifr_mtu > SLMAX)) { 1001 error = EINVAL; 1002 break; 1003 } 1004 sc->sc_if.if_mtu = ifr->ifr_mtu; 1005 break; 1006 1007 case SIOCGIFMTU: 1008 ifr->ifr_mtu = sc->sc_if.if_mtu; 1009 break; 1010 1011 case SIOCADDMULTI: 1012 case SIOCDELMULTI: 1013 if (ifr == 0) { 1014 error = EAFNOSUPPORT; /* XXX */ 1015 break; 1016 } 1017 switch (ifr->ifr_addr.sa_family) { 1018 1019 #ifdef INET 1020 case AF_INET: 1021 break; 1022 #endif 1023 1024 default: 1025 error = EAFNOSUPPORT; 1026 break; 1027 } 1028 break; 1029 1030 default: 1031 error = EINVAL; 1032 } 1033 splx(s); 1034 return (error); 1035 } 1036 #endif 1037