if_sl.c revision 1.95
1 /* $NetBSD: if_sl.c,v 1.95 2005/12/11 23:05:25 thorpej 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 (at) seismo.ARPA 43 * seismo!rick 44 * 45 * Pounded on heavily by Chris Torek (chris (at) 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 (at) 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 1.95 2005/12/11 23:05:25 thorpej 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 static void slintr(void *); 191 192 static int slinit(struct sl_softc *); 193 static struct mbuf *sl_btom(struct sl_softc *, int); 194 195 static int slclose(struct tty *, int); 196 static int slinput(int, struct tty *); 197 static int slioctl(struct ifnet *, u_long, caddr_t); 198 static int slopen(dev_t, struct tty *); 199 static int sloutput(struct ifnet *, struct mbuf *, struct sockaddr *, 200 struct rtentry *); 201 static int slstart(struct tty *); 202 static int sltioctl(struct tty *, u_long, caddr_t, int, struct lwp *); 203 204 static struct linesw slip_disc = { 205 .l_name = "slip", 206 .l_open = slopen, 207 .l_close = slclose, 208 .l_read = ttyerrio, 209 .l_write = ttyerrio, 210 .l_ioctl = sltioctl, 211 .l_rint = slinput, 212 .l_start = slstart, 213 .l_modem = nullmodem, 214 .l_poll = ttyerrpoll 215 }; 216 217 void slattach(void); 218 219 void 220 slattach(void) 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 proc *p = curproc; /* XXX */ 303 struct sl_softc *sc; 304 int error; 305 int s; 306 307 if ((error = suser(p->p_ucred, &p->p_acflag)) != 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 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 316 sc->sc_si = softintr_establish(IPL_SOFTNET, 317 slintr, sc); 318 if (sc->sc_si == NULL) 319 return (ENOMEM); 320 #endif 321 if (slinit(sc) == 0) { 322 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 323 softintr_disestablish(sc->sc_si); 324 #endif 325 return (ENOBUFS); 326 } 327 tp->t_sc = (caddr_t)sc; 328 sc->sc_ttyp = tp; 329 sc->sc_if.if_baudrate = tp->t_ospeed; 330 s = spltty(); 331 tp->t_state |= TS_ISOPEN | TS_XCLUDE; 332 splx(s); 333 ttyflush(tp, FREAD | FWRITE); 334 #ifdef __NetBSD__ 335 /* 336 * make sure tty output queue is large enough 337 * to hold a full-sized packet (including frame 338 * end, and a possible extra frame end). full-sized 339 * packet occupies a max of 2*SLMAX bytes (because 340 * of possible escapes), and add two on for frame 341 * ends. 342 */ 343 s = spltty(); 344 if (tp->t_outq.c_cn < 2*SLMAX+2) { 345 sc->sc_oldbufsize = tp->t_outq.c_cn; 346 sc->sc_oldbufquot = tp->t_outq.c_cq != 0; 347 348 clfree(&tp->t_outq); 349 error = clalloc(&tp->t_outq, 2*SLMAX+2, 0); 350 if (error) { 351 splx(s); 352 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 353 softintr_disestablish(sc->sc_si); 354 #endif 355 /* 356 * clalloc() might return -1 which 357 * is no good, so we need to return 358 * something else. 359 */ 360 return (ENOMEM); /* XXX ?! */ 361 } 362 } else 363 sc->sc_oldbufsize = sc->sc_oldbufquot = 0; 364 splx(s); 365 #endif /* __NetBSD__ */ 366 return (0); 367 } 368 return (ENXIO); 369 } 370 371 /* 372 * Line specific close routine. 373 * Detach the tty from the sl unit. 374 */ 375 static int 376 slclose(struct tty *tp, int flag) 377 { 378 struct sl_softc *sc; 379 int s; 380 381 ttywflush(tp); 382 sc = tp->t_sc; 383 384 if (sc != NULL) { 385 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 386 softintr_disestablish(sc->sc_si); 387 #endif 388 s = splnet(); 389 if_down(&sc->sc_if); 390 IF_PURGE(&sc->sc_fastq); 391 splx(s); 392 393 s = spltty(); 394 ttyldisc_release(tp->t_linesw); 395 tp->t_linesw = ttyldisc_default(); 396 tp->t_state = 0; 397 398 sc->sc_ttyp = NULL; 399 tp->t_sc = NULL; 400 401 m_freem(sc->sc_mbuf); 402 sc->sc_mbuf = NULL; 403 sc->sc_ep = sc->sc_mp = sc->sc_pktstart = NULL; 404 IF_PURGE(&sc->sc_inq); 405 406 /* 407 * If necessary, install a new outq buffer of the 408 * appropriate size. 409 */ 410 if (sc->sc_oldbufsize != 0) { 411 clfree(&tp->t_outq); 412 clalloc(&tp->t_outq, sc->sc_oldbufsize, 413 sc->sc_oldbufquot); 414 } 415 splx(s); 416 } 417 418 return (0); 419 } 420 421 /* 422 * Line specific (tty) ioctl routine. 423 * Provide a way to get the sl unit number. 424 */ 425 /* ARGSUSED */ 426 static int 427 sltioctl(struct tty *tp, u_long cmd, caddr_t data, int flag, struct lwp *l) 428 { 429 struct sl_softc *sc = (struct sl_softc *)tp->t_sc; 430 431 switch (cmd) { 432 case SLIOCGUNIT: 433 *(int *)data = sc->sc_unit; /* XXX */ 434 break; 435 436 default: 437 return (EPASSTHROUGH); 438 } 439 return (0); 440 } 441 442 /* 443 * Queue a packet. Start transmission if not active. 444 * Compression happens in slintr(); if we do it here, IP TOS 445 * will cause us to not compress "background" packets, because 446 * ordering gets trashed. It can be done for all packets in slintr(). 447 */ 448 static int 449 sloutput(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst, 450 struct rtentry *rtp) 451 { 452 struct sl_softc *sc = ifp->if_softc; 453 struct ip *ip; 454 struct ifqueue *ifq = NULL; 455 int s, error; 456 ALTQ_DECL(struct altq_pktattr pktattr;) 457 458 IFQ_CLASSIFY(&ifp->if_snd, m, dst->sa_family, &pktattr); 459 460 /* 461 * `Cannot happen' (see slioctl). Someday we will extend 462 * the line protocol to support other address families. 463 */ 464 if (dst->sa_family != AF_INET) { 465 printf("%s: af%d not supported\n", sc->sc_if.if_xname, 466 dst->sa_family); 467 m_freem(m); 468 sc->sc_if.if_noproto++; 469 return (EAFNOSUPPORT); 470 } 471 472 if (sc->sc_ttyp == NULL) { 473 m_freem(m); 474 return (ENETDOWN); /* sort of */ 475 } 476 if ((sc->sc_ttyp->t_state & TS_CARR_ON) == 0 && 477 (sc->sc_ttyp->t_cflag & CLOCAL) == 0) { 478 m_freem(m); 479 printf("%s: no carrier and not local\n", sc->sc_if.if_xname); 480 return (EHOSTUNREACH); 481 } 482 ip = mtod(m, struct ip *); 483 #ifdef INET 484 if (sc->sc_if.if_flags & SC_NOICMP && ip->ip_p == IPPROTO_ICMP) { 485 m_freem(m); 486 return (ENETRESET); /* XXX ? */ 487 } 488 #endif 489 490 s = spltty(); 491 if (sc->sc_oqlen && sc->sc_ttyp->t_outq.c_cc == sc->sc_oqlen) { 492 struct timeval tv; 493 494 /* if output's been stalled for too long, and restart */ 495 timersub(&time, &sc->sc_lastpacket, &tv); 496 if (tv.tv_sec > 0) { 497 sc->sc_otimeout++; 498 slstart(sc->sc_ttyp); 499 } 500 } 501 splx(s); 502 503 s = splnet(); 504 #ifdef INET 505 if ((ip->ip_tos & IPTOS_LOWDELAY) != 0) 506 ifq = &sc->sc_fastq; 507 #endif 508 if ((error = ifq_enqueue2(ifp, ifq, m ALTQ_COMMA 509 ALTQ_DECL(&pktattr))) != 0) { 510 splx(s); 511 return error; 512 } 513 sc->sc_lastpacket = time; 514 splx(s); 515 516 s = spltty(); 517 if ((sc->sc_oqlen = sc->sc_ttyp->t_outq.c_cc) == 0) 518 slstart(sc->sc_ttyp); 519 splx(s); 520 521 return (0); 522 } 523 524 /* 525 * Start output on interface. Get another datagram 526 * to send from the interface queue and map it to 527 * the interface before starting output. 528 */ 529 static int 530 slstart(struct tty *tp) 531 { 532 struct sl_softc *sc = tp->t_sc; 533 534 /* 535 * If there is more in the output queue, just send it now. 536 * We are being called in lieu of ttstart and must do what 537 * it would. 538 */ 539 if (tp->t_outq.c_cc != 0) { 540 (*tp->t_oproc)(tp); 541 if (tp->t_outq.c_cc > SLIP_HIWAT) 542 return (0); 543 } 544 545 /* 546 * This happens briefly when the line shuts down. 547 */ 548 if (sc == NULL) 549 return (0); 550 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 551 softintr_schedule(sc->sc_si); 552 #else 553 { 554 int s = splhigh(); 555 schednetisr(NETISR_SLIP); 556 splx(s); 557 } 558 #endif 559 return (0); 560 } 561 562 /* 563 * Copy data buffer to mbuf chain; add ifnet pointer. 564 */ 565 static struct mbuf * 566 sl_btom(struct sl_softc *sc, int len) 567 { 568 struct mbuf *m; 569 570 /* 571 * Allocate a new input buffer and swap. 572 */ 573 m = sc->sc_mbuf; 574 MGETHDR(sc->sc_mbuf, M_DONTWAIT, MT_DATA); 575 if (sc->sc_mbuf == NULL) { 576 sc->sc_mbuf = m; 577 return (NULL); 578 } 579 MCLGET(sc->sc_mbuf, M_DONTWAIT); 580 if ((sc->sc_mbuf->m_flags & M_EXT) == 0) { 581 m_freem(sc->sc_mbuf); 582 sc->sc_mbuf = m; 583 return (NULL); 584 } 585 sc->sc_ep = (u_char *) sc->sc_mbuf->m_ext.ext_buf + 586 sc->sc_mbuf->m_ext.ext_size; 587 588 m->m_data = sc->sc_pktstart; 589 590 m->m_pkthdr.len = m->m_len = len; 591 m->m_pkthdr.rcvif = &sc->sc_if; 592 return (m); 593 } 594 595 /* 596 * tty interface receiver interrupt. 597 */ 598 static int 599 slinput(int c, struct tty *tp) 600 { 601 struct sl_softc *sc; 602 struct mbuf *m; 603 int len; 604 605 tk_nin++; 606 sc = (struct sl_softc *)tp->t_sc; 607 if (sc == NULL) 608 return (0); 609 if ((c & TTY_ERRORMASK) || ((tp->t_state & TS_CARR_ON) == 0 && 610 (tp->t_cflag & CLOCAL) == 0)) { 611 sc->sc_flags |= SC_ERROR; 612 return (0); 613 } 614 c &= TTY_CHARMASK; 615 616 ++sc->sc_if.if_ibytes; 617 618 if (sc->sc_if.if_flags & IFF_DEBUG) { 619 if (c == ABT_ESC) { 620 /* 621 * If we have a previous abort, see whether 622 * this one is within the time limit. 623 */ 624 if (sc->sc_abortcount && 625 time.tv_sec >= sc->sc_starttime + ABT_WINDOW) 626 sc->sc_abortcount = 0; 627 /* 628 * If we see an abort after "idle" time, count it; 629 * record when the first abort escape arrived. 630 */ 631 if (time.tv_sec >= sc->sc_lasttime + ABT_IDLE) { 632 if (++sc->sc_abortcount == 1) 633 sc->sc_starttime = time.tv_sec; 634 if (sc->sc_abortcount >= ABT_COUNT) { 635 slclose(tp, 0); 636 return (0); 637 } 638 } 639 } else 640 sc->sc_abortcount = 0; 641 sc->sc_lasttime = time.tv_sec; 642 } 643 644 switch (c) { 645 646 case TRANS_FRAME_ESCAPE: 647 if (sc->sc_escape) 648 c = FRAME_ESCAPE; 649 break; 650 651 case TRANS_FRAME_END: 652 if (sc->sc_escape) 653 c = FRAME_END; 654 break; 655 656 case FRAME_ESCAPE: 657 sc->sc_escape = 1; 658 return (0); 659 660 case FRAME_END: 661 if(sc->sc_flags & SC_ERROR) { 662 sc->sc_flags &= ~SC_ERROR; 663 goto newpack; 664 } 665 len = sc->sc_mp - sc->sc_pktstart; 666 if (len < 3) 667 /* less than min length packet - ignore */ 668 goto newpack; 669 670 m = sl_btom(sc, len); 671 if (m == NULL) 672 goto error; 673 674 IF_ENQUEUE(&sc->sc_inq, m); 675 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 676 softintr_schedule(sc->sc_si); 677 #else 678 { 679 int s = splhigh(); 680 schednetisr(NETISR_SLIP); 681 splx(s); 682 } 683 #endif 684 goto newpack; 685 } 686 if (sc->sc_mp < sc->sc_ep) { 687 *sc->sc_mp++ = c; 688 sc->sc_escape = 0; 689 return (0); 690 } 691 692 /* can't put lower; would miss an extra frame */ 693 sc->sc_flags |= SC_ERROR; 694 695 error: 696 sc->sc_if.if_ierrors++; 697 newpack: 698 sc->sc_mp = sc->sc_pktstart = (u_char *) sc->sc_mbuf->m_ext.ext_buf + 699 BUFOFFSET; 700 sc->sc_escape = 0; 701 702 return (0); 703 } 704 705 #ifndef __HAVE_GENERIC_SOFT_INTERRUPTS 706 void 707 slnetisr(void) 708 { 709 struct sl_softc *sc; 710 711 LIST_FOREACH(sc, &sl_softc_list, sc_iflist) { 712 if (sc->sc_ttyp == NULL) 713 continue; 714 slintr(sc); 715 } 716 } 717 #endif 718 719 static void 720 slintr(void *arg) 721 { 722 struct sl_softc *sc = arg; 723 struct tty *tp = sc->sc_ttyp; 724 struct mbuf *m; 725 int s, len; 726 u_char *pktstart; 727 #ifdef INET 728 u_char c; 729 #endif 730 #if NBPFILTER > 0 731 u_char chdr[CHDR_LEN]; 732 #endif 733 734 KASSERT(tp != NULL); 735 736 /* 737 * Output processing loop. 738 */ 739 for (;;) { 740 #ifdef INET 741 struct ip *ip; 742 #endif 743 struct mbuf *m2; 744 #if NBPFILTER > 0 745 struct mbuf *bpf_m; 746 #endif 747 748 /* 749 * Do not remove the packet from the queue if it 750 * doesn't look like it will fit into the current 751 * serial output queue. With a packet full of 752 * escapes, this could be as bad as MTU*2+2. 753 */ 754 s = spltty(); 755 if (tp->t_outq.c_cn - tp->t_outq.c_cc < 756 2*sc->sc_if.if_mtu+2) { 757 splx(s); 758 break; 759 } 760 splx(s); 761 762 /* 763 * Get a packet and send it to the interface. 764 */ 765 s = splnet(); 766 IF_DEQUEUE(&sc->sc_fastq, m); 767 if (m) 768 sc->sc_if.if_omcasts++; /* XXX */ 769 else 770 IFQ_DEQUEUE(&sc->sc_if.if_snd, m); 771 splx(s); 772 773 if (m == NULL) 774 break; 775 776 /* 777 * We do the header compression here rather than in 778 * sloutput() because the packets will be out of order 779 * if we are using TOS queueing, and the connection 780 * ID compression will get munged when this happens. 781 */ 782 #if NBPFILTER > 0 783 if (sc->sc_if.if_bpf) { 784 /* 785 * We need to save the TCP/IP header before 786 * it's compressed. To avoid complicated 787 * code, we just make a deep copy of the 788 * entire packet (since this is a serial 789 * line, packets should be short and/or the 790 * copy should be negligible cost compared 791 * to the packet transmission time). 792 */ 793 bpf_m = m_dup(m, 0, M_COPYALL, M_DONTWAIT); 794 } else 795 bpf_m = NULL; 796 #endif 797 #ifdef INET 798 if ((ip = mtod(m, struct ip *))->ip_p == IPPROTO_TCP) { 799 if (sc->sc_if.if_flags & SC_COMPRESS) 800 *mtod(m, u_char *) |= 801 sl_compress_tcp(m, ip, 802 &sc->sc_comp, 1); 803 } 804 #endif 805 #if NBPFILTER > 0 806 if (sc->sc_if.if_bpf && bpf_m != NULL) 807 bpf_mtap_sl_out(sc->sc_if.if_bpf, mtod(m, u_char *), 808 bpf_m); 809 #endif 810 sc->sc_lastpacket = time; 811 812 s = spltty(); 813 814 /* 815 * The extra FRAME_END will start up a new packet, 816 * and thus will flush any accumulated garbage. We 817 * do this whenever the line may have been idle for 818 * some time. 819 */ 820 if (tp->t_outq.c_cc == 0) { 821 sc->sc_if.if_obytes++; 822 (void) putc(FRAME_END, &tp->t_outq); 823 } 824 825 while (m) { 826 u_char *bp, *cp, *ep; 827 828 bp = cp = mtod(m, u_char *); 829 ep = cp + m->m_len; 830 while (cp < ep) { 831 /* 832 * Find out how many bytes in the 833 * string we can handle without 834 * doing something special. 835 */ 836 while (cp < ep) { 837 switch (*cp++) { 838 case FRAME_ESCAPE: 839 case FRAME_END: 840 cp--; 841 goto out; 842 } 843 } 844 out: 845 if (cp > bp) { 846 /* 847 * Put N characters at once 848 * into the tty output queue. 849 */ 850 if (b_to_q(bp, cp - bp, 851 &tp->t_outq)) 852 break; 853 sc->sc_if.if_obytes += cp - bp; 854 } 855 /* 856 * If there are characters left in 857 * the mbuf, the first one must be 858 * special.. Put it out in a different 859 * form. 860 */ 861 if (cp < ep) { 862 if (putc(FRAME_ESCAPE, 863 &tp->t_outq)) 864 break; 865 if (putc(*cp++ == FRAME_ESCAPE ? 866 TRANS_FRAME_ESCAPE : 867 TRANS_FRAME_END, 868 &tp->t_outq)) { 869 (void) 870 unputc(&tp->t_outq); 871 break; 872 } 873 sc->sc_if.if_obytes += 2; 874 } 875 bp = cp; 876 } 877 MFREE(m, m2); 878 m = m2; 879 } 880 881 if (putc(FRAME_END, &tp->t_outq)) { 882 /* 883 * Not enough room. Remove a char to make 884 * room and end the packet normally. If 885 * you get many collisions (more than one 886 * or two a day), you probably do not have 887 * enough clists and you should increase 888 * "nclist" in param.c 889 */ 890 (void) unputc(&tp->t_outq); 891 (void) putc(FRAME_END, &tp->t_outq); 892 sc->sc_if.if_collisions++; 893 } else { 894 sc->sc_if.if_obytes++; 895 sc->sc_if.if_opackets++; 896 } 897 898 /* 899 * We now have characters in the output queue, 900 * kick the serial port. 901 */ 902 (*tp->t_oproc)(tp); 903 splx(s); 904 } 905 906 /* 907 * Input processing loop. 908 */ 909 for (;;) { 910 s = spltty(); 911 IF_DEQUEUE(&sc->sc_inq, m); 912 splx(s); 913 if (m == NULL) 914 break; 915 pktstart = mtod(m, u_char *); 916 len = m->m_pkthdr.len; 917 #if NBPFILTER > 0 918 if (sc->sc_if.if_bpf) { 919 /* 920 * Save the compressed header, so we 921 * can tack it on later. Note that we 922 * will end up copying garbage in some 923 * cases but this is okay. We remember 924 * where the buffer started so we can 925 * compute the new header length. 926 */ 927 memcpy(chdr, pktstart, CHDR_LEN); 928 } 929 #endif /* NBPFILTER > 0 */ 930 #ifdef INET 931 if ((c = (*pktstart & 0xf0)) != (IPVERSION << 4)) { 932 if (c & 0x80) 933 c = TYPE_COMPRESSED_TCP; 934 else if (c == TYPE_UNCOMPRESSED_TCP) 935 *pktstart &= 0x4f; /* XXX */ 936 /* 937 * We've got something that's not an IP 938 * packet. If compression is enabled, 939 * try to decompress it. Otherwise, if 940 * `auto-enable' compression is on and 941 * it's a reasonable packet, decompress 942 * it and then enable compression. 943 * Otherwise, drop it. 944 */ 945 if (sc->sc_if.if_flags & SC_COMPRESS) { 946 len = sl_uncompress_tcp(&pktstart, len, 947 (u_int)c, &sc->sc_comp); 948 if (len <= 0) { 949 m_freem(m); 950 continue; 951 } 952 } else if ((sc->sc_if.if_flags & SC_AUTOCOMP) && 953 c == TYPE_UNCOMPRESSED_TCP && len >= 40) { 954 len = sl_uncompress_tcp(&pktstart, len, 955 (u_int)c, &sc->sc_comp); 956 if (len <= 0) { 957 m_freem(m); 958 continue; 959 } 960 sc->sc_if.if_flags |= SC_COMPRESS; 961 } else { 962 m_freem(m); 963 continue; 964 } 965 } 966 #endif 967 m->m_data = (caddr_t) pktstart; 968 m->m_pkthdr.len = m->m_len = len; 969 #if NBPFILTER > 0 970 if (sc->sc_if.if_bpf) { 971 bpf_mtap_sl_in(sc->sc_if.if_bpf, chdr, &m); 972 if (m == NULL) 973 continue; 974 } 975 #endif /* NBPFILTER > 0 */ 976 /* 977 * If the packet will fit into a single 978 * header mbuf, copy it into one, to save 979 * memory. 980 */ 981 if (m->m_pkthdr.len < MHLEN) { 982 struct mbuf *n; 983 int pktlen; 984 985 MGETHDR(n, M_DONTWAIT, MT_DATA); 986 pktlen = m->m_pkthdr.len; 987 M_MOVE_PKTHDR(n, m); 988 memcpy(mtod(n, caddr_t), mtod(m, caddr_t), pktlen); 989 n->m_len = m->m_len; 990 m_freem(m); 991 m = n; 992 } 993 994 sc->sc_if.if_ipackets++; 995 sc->sc_lastpacket = time; 996 997 #ifdef INET 998 s = splnet(); 999 if (IF_QFULL(&ipintrq)) { 1000 IF_DROP(&ipintrq); 1001 sc->sc_if.if_ierrors++; 1002 sc->sc_if.if_iqdrops++; 1003 m_freem(m); 1004 } else { 1005 IF_ENQUEUE(&ipintrq, m); 1006 schednetisr(NETISR_IP); 1007 } 1008 splx(s); 1009 #endif 1010 } 1011 } 1012 1013 /* 1014 * Process an ioctl request. 1015 */ 1016 static int 1017 slioctl(struct ifnet *ifp, u_long cmd, caddr_t data) 1018 { 1019 struct ifaddr *ifa = (struct ifaddr *)data; 1020 struct ifreq *ifr = (struct ifreq *)data; 1021 int s = splnet(), error = 0; 1022 struct sl_softc *sc = ifp->if_softc; 1023 1024 switch (cmd) { 1025 1026 case SIOCSIFADDR: 1027 if (ifa->ifa_addr->sa_family == AF_INET) 1028 ifp->if_flags |= IFF_UP; 1029 else 1030 error = EAFNOSUPPORT; 1031 break; 1032 1033 case SIOCSIFDSTADDR: 1034 if (ifa->ifa_addr->sa_family != AF_INET) 1035 error = EAFNOSUPPORT; 1036 break; 1037 1038 case SIOCSIFMTU: 1039 if ((ifr->ifr_mtu < 3) || (ifr->ifr_mtu > SLMAX)) { 1040 error = EINVAL; 1041 break; 1042 } 1043 sc->sc_if.if_mtu = ifr->ifr_mtu; 1044 break; 1045 1046 case SIOCGIFMTU: 1047 ifr->ifr_mtu = sc->sc_if.if_mtu; 1048 break; 1049 1050 case SIOCADDMULTI: 1051 case SIOCDELMULTI: 1052 if (ifr == 0) { 1053 error = EAFNOSUPPORT; /* XXX */ 1054 break; 1055 } 1056 switch (ifr->ifr_addr.sa_family) { 1057 1058 #ifdef INET 1059 case AF_INET: 1060 break; 1061 #endif 1062 1063 default: 1064 error = EAFNOSUPPORT; 1065 break; 1066 } 1067 break; 1068 1069 default: 1070 error = EINVAL; 1071 } 1072 splx(s); 1073 return (error); 1074 } 1075
Indexes created Sun Sep 28 16:09:52 GMT 2025