if_sl.c revision 1.96
1 /* $NetBSD: if_sl.c,v 1.96 2006/03/02 17:20:07 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 (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 1.96 2006/03/02 17:20:07 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 #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 #ifndef __HAVE_GENERIC_SOFT_INTERRUPTS 190 void slnetisr(void); 191 #endif 192 static void slintr(void *); 193 194 static int slinit(struct sl_softc *); 195 static struct mbuf *sl_btom(struct sl_softc *, int); 196 197 static int slclose(struct tty *, int); 198 static int slinput(int, struct tty *); 199 static int slioctl(struct ifnet *, u_long, caddr_t); 200 static int slopen(dev_t, struct tty *); 201 static int sloutput(struct ifnet *, struct mbuf *, struct sockaddr *, 202 struct rtentry *); 203 static int slstart(struct tty *); 204 static int sltioctl(struct tty *, u_long, caddr_t, int, struct lwp *); 205 206 static struct linesw slip_disc = { 207 .l_name = "slip", 208 .l_open = slopen, 209 .l_close = slclose, 210 .l_read = ttyerrio, 211 .l_write = ttyerrio, 212 .l_ioctl = sltioctl, 213 .l_rint = slinput, 214 .l_start = slstart, 215 .l_modem = nullmodem, 216 .l_poll = ttyerrpoll 217 }; 218 219 void slattach(void); 220 221 void 222 slattach(void) 223 { 224 if (ttyldisc_attach(&slip_disc) != 0) 225 panic("slattach"); 226 LIST_INIT(&sl_softc_list); 227 if_clone_attach(&sl_cloner); 228 } 229 230 static int 231 sl_clone_create(struct if_clone *ifc, int unit) 232 { 233 struct sl_softc *sc; 234 235 MALLOC(sc, struct sl_softc *, sizeof(*sc), M_DEVBUF, M_WAIT|M_ZERO); 236 sc->sc_unit = unit; 237 (void)snprintf(sc->sc_if.if_xname, sizeof(sc->sc_if.if_xname), 238 "%s%d", ifc->ifc_name, unit); 239 sc->sc_if.if_softc = sc; 240 sc->sc_if.if_mtu = SLMTU; 241 sc->sc_if.if_flags = IFF_POINTOPOINT | SC_AUTOCOMP | IFF_MULTICAST; 242 sc->sc_if.if_type = IFT_SLIP; 243 sc->sc_if.if_ioctl = slioctl; 244 sc->sc_if.if_output = sloutput; 245 sc->sc_if.if_dlt = DLT_SLIP; 246 sc->sc_fastq.ifq_maxlen = 32; 247 IFQ_SET_READY(&sc->sc_if.if_snd); 248 if_attach(&sc->sc_if); 249 if_alloc_sadl(&sc->sc_if); 250 #if NBPFILTER > 0 251 bpfattach(&sc->sc_if, DLT_SLIP, SLIP_HDRLEN); 252 #endif 253 LIST_INSERT_HEAD(&sl_softc_list, sc, sc_iflist); 254 return 0; 255 } 256 257 static int 258 sl_clone_destroy(struct ifnet *ifp) 259 { 260 struct sl_softc *sc = (struct sl_softc *)ifp->if_softc; 261 262 if (sc->sc_ttyp != NULL) 263 return EBUSY; /* Not removing it */ 264 265 LIST_REMOVE(sc, sc_iflist); 266 267 #if NBPFILTER > 0 268 bpfdetach(ifp); 269 #endif 270 if_detach(ifp); 271 272 FREE(sc, M_DEVBUF); 273 return 0; 274 } 275 276 static int 277 slinit(struct sl_softc *sc) 278 { 279 280 if (sc->sc_mbuf == NULL) { 281 sc->sc_mbuf = m_gethdr(M_WAIT, MT_DATA); 282 m_clget(sc->sc_mbuf, M_WAIT); 283 } 284 sc->sc_ep = (u_char *) sc->sc_mbuf->m_ext.ext_buf + 285 sc->sc_mbuf->m_ext.ext_size; 286 sc->sc_mp = sc->sc_pktstart = (u_char *) sc->sc_mbuf->m_ext.ext_buf + 287 BUFOFFSET; 288 289 #ifdef INET 290 sl_compress_init(&sc->sc_comp); 291 #endif 292 293 return (1); 294 } 295 296 /* 297 * Line specific open routine. 298 * Attach the given tty to the first available sl unit. 299 */ 300 /* ARGSUSED */ 301 static int 302 slopen(dev_t dev, struct tty *tp) 303 { 304 struct proc *p = curproc; /* XXX */ 305 struct sl_softc *sc; 306 int error; 307 int s; 308 309 if ((error = suser(p->p_ucred, &p->p_acflag)) != 0) 310 return (error); 311 312 if (tp->t_linesw == &slip_disc) 313 return (0); 314 315 LIST_FOREACH(sc, &sl_softc_list, sc_iflist) 316 if (sc->sc_ttyp == NULL) { 317 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 318 sc->sc_si = softintr_establish(IPL_SOFTNET, 319 slintr, sc); 320 if (sc->sc_si == NULL) 321 return (ENOMEM); 322 #endif 323 if (slinit(sc) == 0) { 324 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 325 softintr_disestablish(sc->sc_si); 326 #endif 327 return (ENOBUFS); 328 } 329 tp->t_sc = (caddr_t)sc; 330 sc->sc_ttyp = tp; 331 sc->sc_if.if_baudrate = tp->t_ospeed; 332 s = spltty(); 333 tp->t_state |= TS_ISOPEN | TS_XCLUDE; 334 splx(s); 335 ttyflush(tp, FREAD | FWRITE); 336 #ifdef __NetBSD__ 337 /* 338 * make sure tty output queue is large enough 339 * to hold a full-sized packet (including frame 340 * end, and a possible extra frame end). full-sized 341 * packet occupies a max of 2*SLMAX bytes (because 342 * of possible escapes), and add two on for frame 343 * ends. 344 */ 345 s = spltty(); 346 if (tp->t_outq.c_cn < 2*SLMAX+2) { 347 sc->sc_oldbufsize = tp->t_outq.c_cn; 348 sc->sc_oldbufquot = tp->t_outq.c_cq != 0; 349 350 clfree(&tp->t_outq); 351 error = clalloc(&tp->t_outq, 2*SLMAX+2, 0); 352 if (error) { 353 splx(s); 354 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 355 softintr_disestablish(sc->sc_si); 356 #endif 357 /* 358 * clalloc() might return -1 which 359 * is no good, so we need to return 360 * something else. 361 */ 362 return (ENOMEM); /* XXX ?! */ 363 } 364 } else 365 sc->sc_oldbufsize = sc->sc_oldbufquot = 0; 366 splx(s); 367 #endif /* __NetBSD__ */ 368 return (0); 369 } 370 return (ENXIO); 371 } 372 373 /* 374 * Line specific close routine. 375 * Detach the tty from the sl unit. 376 */ 377 static int 378 slclose(struct tty *tp, int flag) 379 { 380 struct sl_softc *sc; 381 int s; 382 383 ttywflush(tp); 384 sc = tp->t_sc; 385 386 if (sc != NULL) { 387 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 388 softintr_disestablish(sc->sc_si); 389 #endif 390 s = splnet(); 391 if_down(&sc->sc_if); 392 IF_PURGE(&sc->sc_fastq); 393 splx(s); 394 395 s = spltty(); 396 ttyldisc_release(tp->t_linesw); 397 tp->t_linesw = ttyldisc_default(); 398 tp->t_state = 0; 399 400 sc->sc_ttyp = NULL; 401 tp->t_sc = NULL; 402 403 m_freem(sc->sc_mbuf); 404 sc->sc_mbuf = NULL; 405 sc->sc_ep = sc->sc_mp = sc->sc_pktstart = NULL; 406 IF_PURGE(&sc->sc_inq); 407 408 /* 409 * If necessary, install a new outq buffer of the 410 * appropriate size. 411 */ 412 if (sc->sc_oldbufsize != 0) { 413 clfree(&tp->t_outq); 414 clalloc(&tp->t_outq, sc->sc_oldbufsize, 415 sc->sc_oldbufquot); 416 } 417 splx(s); 418 } 419 420 return (0); 421 } 422 423 /* 424 * Line specific (tty) ioctl routine. 425 * Provide a way to get the sl unit number. 426 */ 427 /* ARGSUSED */ 428 static int 429 sltioctl(struct tty *tp, u_long cmd, caddr_t data, int flag, struct lwp *l) 430 { 431 struct sl_softc *sc = (struct sl_softc *)tp->t_sc; 432 433 switch (cmd) { 434 case SLIOCGUNIT: 435 *(int *)data = sc->sc_unit; /* XXX */ 436 break; 437 438 default: 439 return (EPASSTHROUGH); 440 } 441 return (0); 442 } 443 444 /* 445 * Queue a packet. Start transmission if not active. 446 * Compression happens in slintr(); if we do it here, IP TOS 447 * will cause us to not compress "background" packets, because 448 * ordering gets trashed. It can be done for all packets in slintr(). 449 */ 450 static int 451 sloutput(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst, 452 struct rtentry *rtp) 453 { 454 struct sl_softc *sc = ifp->if_softc; 455 struct ip *ip; 456 struct ifqueue *ifq = NULL; 457 int s, error; 458 ALTQ_DECL(struct altq_pktattr pktattr;) 459 460 IFQ_CLASSIFY(&ifp->if_snd, m, dst->sa_family, &pktattr); 461 462 /* 463 * `Cannot happen' (see slioctl). Someday we will extend 464 * the line protocol to support other address families. 465 */ 466 if (dst->sa_family != AF_INET) { 467 printf("%s: af%d not supported\n", sc->sc_if.if_xname, 468 dst->sa_family); 469 m_freem(m); 470 sc->sc_if.if_noproto++; 471 return (EAFNOSUPPORT); 472 } 473 474 if (sc->sc_ttyp == NULL) { 475 m_freem(m); 476 return (ENETDOWN); /* sort of */ 477 } 478 if ((sc->sc_ttyp->t_state & TS_CARR_ON) == 0 && 479 (sc->sc_ttyp->t_cflag & CLOCAL) == 0) { 480 m_freem(m); 481 printf("%s: no carrier and not local\n", sc->sc_if.if_xname); 482 return (EHOSTUNREACH); 483 } 484 ip = mtod(m, struct ip *); 485 #ifdef INET 486 if (sc->sc_if.if_flags & SC_NOICMP && ip->ip_p == IPPROTO_ICMP) { 487 m_freem(m); 488 return (ENETRESET); /* XXX ? */ 489 } 490 #endif 491 492 s = spltty(); 493 if (sc->sc_oqlen && sc->sc_ttyp->t_outq.c_cc == sc->sc_oqlen) { 494 struct timeval tv; 495 496 /* if output's been stalled for too long, and restart */ 497 timersub(&time, &sc->sc_lastpacket, &tv); 498 if (tv.tv_sec > 0) { 499 sc->sc_otimeout++; 500 slstart(sc->sc_ttyp); 501 } 502 } 503 splx(s); 504 505 s = splnet(); 506 #ifdef INET 507 if ((ip->ip_tos & IPTOS_LOWDELAY) != 0) 508 ifq = &sc->sc_fastq; 509 #endif 510 if ((error = ifq_enqueue2(ifp, ifq, m ALTQ_COMMA 511 ALTQ_DECL(&pktattr))) != 0) { 512 splx(s); 513 return error; 514 } 515 sc->sc_lastpacket = time; 516 splx(s); 517 518 s = spltty(); 519 if ((sc->sc_oqlen = sc->sc_ttyp->t_outq.c_cc) == 0) 520 slstart(sc->sc_ttyp); 521 splx(s); 522 523 return (0); 524 } 525 526 /* 527 * Start output on interface. Get another datagram 528 * to send from the interface queue and map it to 529 * the interface before starting output. 530 */ 531 static int 532 slstart(struct tty *tp) 533 { 534 struct sl_softc *sc = tp->t_sc; 535 536 /* 537 * If there is more in the output queue, just send it now. 538 * We are being called in lieu of ttstart and must do what 539 * it would. 540 */ 541 if (tp->t_outq.c_cc != 0) { 542 (*tp->t_oproc)(tp); 543 if (tp->t_outq.c_cc > SLIP_HIWAT) 544 return (0); 545 } 546 547 /* 548 * This happens briefly when the line shuts down. 549 */ 550 if (sc == NULL) 551 return (0); 552 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 553 softintr_schedule(sc->sc_si); 554 #else 555 { 556 int s = splhigh(); 557 schednetisr(NETISR_SLIP); 558 splx(s); 559 } 560 #endif 561 return (0); 562 } 563 564 /* 565 * Copy data buffer to mbuf chain; add ifnet pointer. 566 */ 567 static struct mbuf * 568 sl_btom(struct sl_softc *sc, int len) 569 { 570 struct mbuf *m; 571 572 /* 573 * Allocate a new input buffer and swap. 574 */ 575 m = sc->sc_mbuf; 576 MGETHDR(sc->sc_mbuf, M_DONTWAIT, MT_DATA); 577 if (sc->sc_mbuf == NULL) { 578 sc->sc_mbuf = m; 579 return (NULL); 580 } 581 MCLGET(sc->sc_mbuf, M_DONTWAIT); 582 if ((sc->sc_mbuf->m_flags & M_EXT) == 0) { 583 m_freem(sc->sc_mbuf); 584 sc->sc_mbuf = m; 585 return (NULL); 586 } 587 sc->sc_ep = (u_char *) sc->sc_mbuf->m_ext.ext_buf + 588 sc->sc_mbuf->m_ext.ext_size; 589 590 m->m_data = sc->sc_pktstart; 591 592 m->m_pkthdr.len = m->m_len = len; 593 m->m_pkthdr.rcvif = &sc->sc_if; 594 return (m); 595 } 596 597 /* 598 * tty interface receiver interrupt. 599 */ 600 static int 601 slinput(int c, struct tty *tp) 602 { 603 struct sl_softc *sc; 604 struct mbuf *m; 605 int len; 606 607 tk_nin++; 608 sc = (struct sl_softc *)tp->t_sc; 609 if (sc == NULL) 610 return (0); 611 if ((c & TTY_ERRORMASK) || ((tp->t_state & TS_CARR_ON) == 0 && 612 (tp->t_cflag & CLOCAL) == 0)) { 613 sc->sc_flags |= SC_ERROR; 614 return (0); 615 } 616 c &= TTY_CHARMASK; 617 618 ++sc->sc_if.if_ibytes; 619 620 if (sc->sc_if.if_flags & IFF_DEBUG) { 621 if (c == ABT_ESC) { 622 /* 623 * If we have a previous abort, see whether 624 * this one is within the time limit. 625 */ 626 if (sc->sc_abortcount && 627 time.tv_sec >= sc->sc_starttime + ABT_WINDOW) 628 sc->sc_abortcount = 0; 629 /* 630 * If we see an abort after "idle" time, count it; 631 * record when the first abort escape arrived. 632 */ 633 if (time.tv_sec >= sc->sc_lasttime + ABT_IDLE) { 634 if (++sc->sc_abortcount == 1) 635 sc->sc_starttime = time.tv_sec; 636 if (sc->sc_abortcount >= ABT_COUNT) { 637 slclose(tp, 0); 638 return (0); 639 } 640 } 641 } else 642 sc->sc_abortcount = 0; 643 sc->sc_lasttime = time.tv_sec; 644 } 645 646 switch (c) { 647 648 case TRANS_FRAME_ESCAPE: 649 if (sc->sc_escape) 650 c = FRAME_ESCAPE; 651 break; 652 653 case TRANS_FRAME_END: 654 if (sc->sc_escape) 655 c = FRAME_END; 656 break; 657 658 case FRAME_ESCAPE: 659 sc->sc_escape = 1; 660 return (0); 661 662 case FRAME_END: 663 if(sc->sc_flags & SC_ERROR) { 664 sc->sc_flags &= ~SC_ERROR; 665 goto newpack; 666 } 667 len = sc->sc_mp - sc->sc_pktstart; 668 if (len < 3) 669 /* less than min length packet - ignore */ 670 goto newpack; 671 672 m = sl_btom(sc, len); 673 if (m == NULL) 674 goto error; 675 676 IF_ENQUEUE(&sc->sc_inq, m); 677 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 678 softintr_schedule(sc->sc_si); 679 #else 680 { 681 int s = splhigh(); 682 schednetisr(NETISR_SLIP); 683 splx(s); 684 } 685 #endif 686 goto newpack; 687 } 688 if (sc->sc_mp < sc->sc_ep) { 689 *sc->sc_mp++ = c; 690 sc->sc_escape = 0; 691 return (0); 692 } 693 694 /* can't put lower; would miss an extra frame */ 695 sc->sc_flags |= SC_ERROR; 696 697 error: 698 sc->sc_if.if_ierrors++; 699 newpack: 700 sc->sc_mp = sc->sc_pktstart = (u_char *) sc->sc_mbuf->m_ext.ext_buf + 701 BUFOFFSET; 702 sc->sc_escape = 0; 703 704 return (0); 705 } 706 707 #ifndef __HAVE_GENERIC_SOFT_INTERRUPTS 708 void 709 slnetisr(void) 710 { 711 struct sl_softc *sc; 712 713 LIST_FOREACH(sc, &sl_softc_list, sc_iflist) { 714 if (sc->sc_ttyp == NULL) 715 continue; 716 slintr(sc); 717 } 718 } 719 #endif 720 721 static void 722 slintr(void *arg) 723 { 724 struct sl_softc *sc = arg; 725 struct tty *tp = sc->sc_ttyp; 726 struct mbuf *m; 727 int s, len; 728 u_char *pktstart; 729 #ifdef INET 730 u_char c; 731 #endif 732 #if NBPFILTER > 0 733 u_char chdr[CHDR_LEN]; 734 #endif 735 736 KASSERT(tp != NULL); 737 738 /* 739 * Output processing loop. 740 */ 741 for (;;) { 742 #ifdef INET 743 struct ip *ip; 744 #endif 745 struct mbuf *m2; 746 #if NBPFILTER > 0 747 struct mbuf *bpf_m; 748 #endif 749 750 /* 751 * Do not remove the packet from the queue if it 752 * doesn't look like it will fit into the current 753 * serial output queue. With a packet full of 754 * escapes, this could be as bad as MTU*2+2. 755 */ 756 s = spltty(); 757 if (tp->t_outq.c_cn - tp->t_outq.c_cc < 758 2*sc->sc_if.if_mtu+2) { 759 splx(s); 760 break; 761 } 762 splx(s); 763 764 /* 765 * Get a packet and send it to the interface. 766 */ 767 s = splnet(); 768 IF_DEQUEUE(&sc->sc_fastq, m); 769 if (m) 770 sc->sc_if.if_omcasts++; /* XXX */ 771 else 772 IFQ_DEQUEUE(&sc->sc_if.if_snd, m); 773 splx(s); 774 775 if (m == NULL) 776 break; 777 778 /* 779 * We do the header compression here rather than in 780 * sloutput() because the packets will be out of order 781 * if we are using TOS queueing, and the connection 782 * ID compression will get munged when this happens. 783 */ 784 #if NBPFILTER > 0 785 if (sc->sc_if.if_bpf) { 786 /* 787 * We need to save the TCP/IP header before 788 * it's compressed. To avoid complicated 789 * code, we just make a deep copy of the 790 * entire packet (since this is a serial 791 * line, packets should be short and/or the 792 * copy should be negligible cost compared 793 * to the packet transmission time). 794 */ 795 bpf_m = m_dup(m, 0, M_COPYALL, M_DONTWAIT); 796 } else 797 bpf_m = NULL; 798 #endif 799 #ifdef INET 800 if ((ip = mtod(m, struct ip *))->ip_p == IPPROTO_TCP) { 801 if (sc->sc_if.if_flags & SC_COMPRESS) 802 *mtod(m, u_char *) |= 803 sl_compress_tcp(m, ip, 804 &sc->sc_comp, 1); 805 } 806 #endif 807 #if NBPFILTER > 0 808 if (sc->sc_if.if_bpf && bpf_m != NULL) 809 bpf_mtap_sl_out(sc->sc_if.if_bpf, mtod(m, u_char *), 810 bpf_m); 811 #endif 812 sc->sc_lastpacket = time; 813 814 s = spltty(); 815 816 /* 817 * The extra FRAME_END will start up a new packet, 818 * and thus will flush any accumulated garbage. We 819 * do this whenever the line may have been idle for 820 * some time. 821 */ 822 if (tp->t_outq.c_cc == 0) { 823 sc->sc_if.if_obytes++; 824 (void) putc(FRAME_END, &tp->t_outq); 825 } 826 827 while (m) { 828 u_char *bp, *cp, *ep; 829 830 bp = cp = mtod(m, u_char *); 831 ep = cp + m->m_len; 832 while (cp < ep) { 833 /* 834 * Find out how many bytes in the 835 * string we can handle without 836 * doing something special. 837 */ 838 while (cp < ep) { 839 switch (*cp++) { 840 case FRAME_ESCAPE: 841 case FRAME_END: 842 cp--; 843 goto out; 844 } 845 } 846 out: 847 if (cp > bp) { 848 /* 849 * Put N characters at once 850 * into the tty output queue. 851 */ 852 if (b_to_q(bp, cp - bp, 853 &tp->t_outq)) 854 break; 855 sc->sc_if.if_obytes += cp - bp; 856 } 857 /* 858 * If there are characters left in 859 * the mbuf, the first one must be 860 * special.. Put it out in a different 861 * form. 862 */ 863 if (cp < ep) { 864 if (putc(FRAME_ESCAPE, 865 &tp->t_outq)) 866 break; 867 if (putc(*cp++ == FRAME_ESCAPE ? 868 TRANS_FRAME_ESCAPE : 869 TRANS_FRAME_END, 870 &tp->t_outq)) { 871 (void) 872 unputc(&tp->t_outq); 873 break; 874 } 875 sc->sc_if.if_obytes += 2; 876 } 877 bp = cp; 878 } 879 MFREE(m, m2); 880 m = m2; 881 } 882 883 if (putc(FRAME_END, &tp->t_outq)) { 884 /* 885 * Not enough room. Remove a char to make 886 * room and end the packet normally. If 887 * you get many collisions (more than one 888 * or two a day), you probably do not have 889 * enough clists and you should increase 890 * "nclist" in param.c 891 */ 892 (void) unputc(&tp->t_outq); 893 (void) putc(FRAME_END, &tp->t_outq); 894 sc->sc_if.if_collisions++; 895 } else { 896 sc->sc_if.if_obytes++; 897 sc->sc_if.if_opackets++; 898 } 899 900 /* 901 * We now have characters in the output queue, 902 * kick the serial port. 903 */ 904 (*tp->t_oproc)(tp); 905 splx(s); 906 } 907 908 /* 909 * Input processing loop. 910 */ 911 for (;;) { 912 s = spltty(); 913 IF_DEQUEUE(&sc->sc_inq, m); 914 splx(s); 915 if (m == NULL) 916 break; 917 pktstart = mtod(m, u_char *); 918 len = m->m_pkthdr.len; 919 #if NBPFILTER > 0 920 if (sc->sc_if.if_bpf) { 921 /* 922 * Save the compressed header, so we 923 * can tack it on later. Note that we 924 * will end up copying garbage in some 925 * cases but this is okay. We remember 926 * where the buffer started so we can 927 * compute the new header length. 928 */ 929 memcpy(chdr, pktstart, CHDR_LEN); 930 } 931 #endif /* NBPFILTER > 0 */ 932 #ifdef INET 933 if ((c = (*pktstart & 0xf0)) != (IPVERSION << 4)) { 934 if (c & 0x80) 935 c = TYPE_COMPRESSED_TCP; 936 else if (c == TYPE_UNCOMPRESSED_TCP) 937 *pktstart &= 0x4f; /* XXX */ 938 /* 939 * We've got something that's not an IP 940 * packet. If compression is enabled, 941 * try to decompress it. Otherwise, if 942 * `auto-enable' compression is on and 943 * it's a reasonable packet, decompress 944 * it and then enable compression. 945 * Otherwise, drop it. 946 */ 947 if (sc->sc_if.if_flags & SC_COMPRESS) { 948 len = sl_uncompress_tcp(&pktstart, len, 949 (u_int)c, &sc->sc_comp); 950 if (len <= 0) { 951 m_freem(m); 952 continue; 953 } 954 } else if ((sc->sc_if.if_flags & SC_AUTOCOMP) && 955 c == TYPE_UNCOMPRESSED_TCP && len >= 40) { 956 len = sl_uncompress_tcp(&pktstart, len, 957 (u_int)c, &sc->sc_comp); 958 if (len <= 0) { 959 m_freem(m); 960 continue; 961 } 962 sc->sc_if.if_flags |= SC_COMPRESS; 963 } else { 964 m_freem(m); 965 continue; 966 } 967 } 968 #endif 969 m->m_data = (caddr_t) pktstart; 970 m->m_pkthdr.len = m->m_len = len; 971 #if NBPFILTER > 0 972 if (sc->sc_if.if_bpf) { 973 bpf_mtap_sl_in(sc->sc_if.if_bpf, chdr, &m); 974 if (m == NULL) 975 continue; 976 } 977 #endif /* NBPFILTER > 0 */ 978 /* 979 * If the packet will fit into a single 980 * header mbuf, copy it into one, to save 981 * memory. 982 */ 983 if (m->m_pkthdr.len < MHLEN) { 984 struct mbuf *n; 985 int pktlen; 986 987 MGETHDR(n, M_DONTWAIT, MT_DATA); 988 pktlen = m->m_pkthdr.len; 989 M_MOVE_PKTHDR(n, m); 990 memcpy(mtod(n, caddr_t), mtod(m, caddr_t), pktlen); 991 n->m_len = m->m_len; 992 m_freem(m); 993 m = n; 994 } 995 996 sc->sc_if.if_ipackets++; 997 sc->sc_lastpacket = time; 998 999 #ifdef INET 1000 s = splnet(); 1001 if (IF_QFULL(&ipintrq)) { 1002 IF_DROP(&ipintrq); 1003 sc->sc_if.if_ierrors++; 1004 sc->sc_if.if_iqdrops++; 1005 m_freem(m); 1006 } else { 1007 IF_ENQUEUE(&ipintrq, m); 1008 schednetisr(NETISR_IP); 1009 } 1010 splx(s); 1011 #endif 1012 } 1013 } 1014 1015 /* 1016 * Process an ioctl request. 1017 */ 1018 static int 1019 slioctl(struct ifnet *ifp, u_long cmd, caddr_t data) 1020 { 1021 struct ifaddr *ifa = (struct ifaddr *)data; 1022 struct ifreq *ifr = (struct ifreq *)data; 1023 int s = splnet(), error = 0; 1024 struct sl_softc *sc = ifp->if_softc; 1025 struct ppp_stats *psp; 1026 struct ppp_comp_stats *pcp; 1027 1028 switch (cmd) { 1029 1030 case SIOCSIFADDR: 1031 if (ifa->ifa_addr->sa_family == AF_INET) 1032 ifp->if_flags |= IFF_UP; 1033 else 1034 error = EAFNOSUPPORT; 1035 break; 1036 1037 case SIOCSIFDSTADDR: 1038 if (ifa->ifa_addr->sa_family != AF_INET) 1039 error = EAFNOSUPPORT; 1040 break; 1041 1042 case SIOCSIFMTU: 1043 if ((ifr->ifr_mtu < 3) || (ifr->ifr_mtu > SLMAX)) { 1044 error = EINVAL; 1045 break; 1046 } 1047 sc->sc_if.if_mtu = ifr->ifr_mtu; 1048 break; 1049 1050 case SIOCGIFMTU: 1051 ifr->ifr_mtu = sc->sc_if.if_mtu; 1052 break; 1053 1054 case SIOCADDMULTI: 1055 case SIOCDELMULTI: 1056 if (ifr == 0) { 1057 error = EAFNOSUPPORT; /* XXX */ 1058 break; 1059 } 1060 switch (ifr->ifr_addr.sa_family) { 1061 1062 #ifdef INET 1063 case AF_INET: 1064 break; 1065 #endif 1066 1067 default: 1068 error = EAFNOSUPPORT; 1069 break; 1070 } 1071 break; 1072 1073 case SIOCGPPPSTATS: 1074 psp = &((struct ifpppstatsreq *) data)->stats; 1075 (void)memset(psp, 0, sizeof(*psp)); 1076 psp->p.ppp_ibytes = sc->sc_if.if_ibytes; 1077 psp->p.ppp_ipackets = sc->sc_if.if_ipackets; 1078 psp->p.ppp_ierrors = sc->sc_if.if_ierrors; 1079 psp->p.ppp_obytes = sc->sc_if.if_obytes; 1080 psp->p.ppp_opackets = sc->sc_if.if_opackets; 1081 psp->p.ppp_oerrors = sc->sc_if.if_oerrors; 1082 #ifdef INET 1083 psp->vj.vjs_packets = sc->sc_comp.sls_packets; 1084 psp->vj.vjs_compressed = sc->sc_comp.sls_compressed; 1085 psp->vj.vjs_searches = sc->sc_comp.sls_searches; 1086 psp->vj.vjs_misses = sc->sc_comp.sls_misses; 1087 psp->vj.vjs_uncompressedin = sc->sc_comp.sls_uncompressedin; 1088 psp->vj.vjs_compressedin = sc->sc_comp.sls_compressedin; 1089 psp->vj.vjs_errorin = sc->sc_comp.sls_errorin; 1090 psp->vj.vjs_tossed = sc->sc_comp.sls_tossed; 1091 #endif 1092 break; 1093 1094 case SIOCGPPPCSTATS: 1095 pcp = &((struct ifpppcstatsreq *) data)->stats; 1096 (void)memset(pcp, 0, sizeof(*pcp)); 1097 break; 1098 1099 default: 1100 error = EINVAL; 1101 } 1102 splx(s); 1103 return (error); 1104 } 1105
Indexes created Mon Sep 29 03:10:08 GMT 2025