1 /* $NetBSD: if_sl.c,v 1.101 2006/10/12 01:32:28 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 1.101 2006/10/12 01:32:28 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 #include <sys/kauth.h> 83 #endif 84 85 #include <machine/cpu.h> 86 #include <machine/intr.h> 87 88 #include <net/if.h> 89 #include <net/if_types.h> 90 #include <net/netisr.h> 91 #include <net/route.h> 92 93 #ifdef INET 94 #include <netinet/in.h> 95 #include <netinet/in_systm.h> 96 #include <netinet/in_var.h> 97 #include <netinet/ip.h> 98 #endif 99 100 #include <net/slcompress.h> 101 #include <net/if_slvar.h> 102 #include <net/slip.h> 103 #include <net/ppp_defs.h> 104 #include <net/if_ppp.h> 105 106 #if NBPFILTER > 0 107 #include <sys/time.h> 108 #include <net/bpf.h> 109 #endif 110 111 /* 112 * SLMAX is a hard limit on input packet size. To simplify the code 113 * and improve performance, we require that packets fit in an mbuf 114 * cluster, and if we get a compressed packet, there's enough extra 115 * room to expand the header into a max length tcp/ip header (128 116 * bytes). So, SLMAX can be at most 117 * MCLBYTES - 128 118 * 119 * SLMTU is a hard limit on output packet size. To insure good 120 * interactive response, SLMTU wants to be the smallest size that 121 * amortizes the header cost. (Remember that even with 122 * type-of-service queuing, we have to wait for any in-progress 123 * packet to finish. I.e., we wait, on the average, 1/2 * mtu / 124 * cps, where cps is the line speed in characters per second. 125 * E.g., 533ms wait for a 1024 byte MTU on a 9600 baud line. The 126 * average compressed header size is 6-8 bytes so any MTU > 90 127 * bytes will give us 90% of the line bandwidth. A 100ms wait is 128 * tolerable (500ms is not), so want an MTU around 296. (Since TCP 129 * will send 256 byte segments (to allow for 40 byte headers), the 130 * typical packet size on the wire will be around 260 bytes). In 131 * 4.3tahoe+ systems, we can set an MTU in a route so we do that & 132 * leave the interface MTU relatively high (so we don't IP fragment 133 * when acting as a gateway to someone using a stupid MTU). 134 * 135 * Similar considerations apply to SLIP_HIWAT: It's the amount of 136 * data that will be queued 'downstream' of us (i.e., in clists 137 * waiting to be picked up by the tty output interrupt). If we 138 * queue a lot of data downstream, it's immune to our t.o.s. queuing. 139 * E.g., if SLIP_HIWAT is 1024, the interactive traffic in mixed 140 * telnet/ftp will see a 1 sec wait, independent of the mtu (the 141 * wait is dependent on the ftp window size but that's typically 142 * 1k - 4k). So, we want SLIP_HIWAT just big enough to amortize 143 * the cost (in idle time on the wire) of the tty driver running 144 * off the end of its clists & having to call back slstart for a 145 * new packet. For a tty interface with any buffering at all, this 146 * cost will be zero. Even with a totally brain dead interface (like 147 * the one on a typical workstation), the cost will be <= 1 character 148 * time. So, setting SLIP_HIWAT to ~100 guarantees that we'll lose 149 * at most 1% while maintaining good interactive response. 150 */ 151 #define BUFOFFSET (128+sizeof(struct ifnet **)+SLIP_HDRLEN) 152 #define SLMAX (MCLBYTES - BUFOFFSET) 153 #define SLBUFSIZE (SLMAX + BUFOFFSET) 154 #ifndef SLMTU 155 #define SLMTU 296 156 #endif 157 #if (SLMTU < 3) 158 #error SLMTU way too small. 159 #endif 160 #define SLIP_HIWAT roundup(50,CBSIZE) 161 #ifndef __NetBSD__ /* XXX - cgd */ 162 #define CLISTRESERVE 1024 /* Can't let clists get too low */ 163 #endif /* !__NetBSD__ */ 164 165 /* 166 * SLIP ABORT ESCAPE MECHANISM: 167 * (inspired by HAYES modem escape arrangement) 168 * 1sec escape 1sec escape 1sec escape { 1sec escape 1sec escape } 169 * within window time signals a "soft" exit from slip mode by remote end 170 * if the IFF_DEBUG flag is on. 171 */ 172 #define ABT_ESC '\033' /* can't be t_intr - distant host must know it*/ 173 #define ABT_IDLE 1 /* in seconds - idle before an escape */ 174 #define ABT_COUNT 3 /* count of escapes for abort */ 175 #define ABT_WINDOW (ABT_COUNT*2+2) /* in seconds - time to count */ 176 177 static int sl_clone_create(struct if_clone *, int); 178 static int sl_clone_destroy(struct ifnet *); 179 180 static LIST_HEAD(, sl_softc) sl_softc_list; 181 182 struct if_clone sl_cloner = 183 IF_CLONE_INITIALIZER("sl", sl_clone_create, sl_clone_destroy); 184 185 #define FRAME_END 0xc0 /* Frame End */ 186 #define FRAME_ESCAPE 0xdb /* Frame Esc */ 187 #define TRANS_FRAME_END 0xdc /* transposed frame end */ 188 #define TRANS_FRAME_ESCAPE 0xdd /* transposed frame esc */ 189 190 #ifndef __HAVE_GENERIC_SOFT_INTERRUPTS 191 void slnetisr(void); 192 #endif 193 static void slintr(void *); 194 195 static int slinit(struct sl_softc *); 196 static struct mbuf *sl_btom(struct sl_softc *, int); 197 198 static int slclose(struct tty *, int); 199 static int slinput(int, struct tty *); 200 static int slioctl(struct ifnet *, u_long, caddr_t); 201 static int slopen(dev_t, struct tty *); 202 static int sloutput(struct ifnet *, struct mbuf *, struct sockaddr *, 203 struct rtentry *); 204 static int slstart(struct tty *); 205 static int sltioctl(struct tty *, u_long, caddr_t, int, struct lwp *); 206 207 static struct linesw slip_disc = { 208 .l_name = "slip", 209 .l_open = slopen, 210 .l_close = slclose, 211 .l_read = ttyerrio, 212 .l_write = ttyerrio, 213 .l_ioctl = sltioctl, 214 .l_rint = slinput, 215 .l_start = slstart, 216 .l_modem = nullmodem, 217 .l_poll = ttyerrpoll 218 }; 219 220 void slattach(void); 221 222 void 223 slattach(void) 224 { 225 226 if (ttyldisc_attach(&slip_disc) != 0) 227 panic("slattach"); 228 LIST_INIT(&sl_softc_list); 229 if_clone_attach(&sl_cloner); 230 } 231 232 static int 233 sl_clone_create(struct if_clone *ifc, int unit) 234 { 235 struct sl_softc *sc; 236 237 MALLOC(sc, struct sl_softc *, sizeof(*sc), M_DEVBUF, M_WAIT|M_ZERO); 238 sc->sc_unit = unit; 239 (void)snprintf(sc->sc_if.if_xname, sizeof(sc->sc_if.if_xname), 240 "%s%d", ifc->ifc_name, unit); 241 sc->sc_if.if_softc = sc; 242 sc->sc_if.if_mtu = SLMTU; 243 sc->sc_if.if_flags = IFF_POINTOPOINT | SC_AUTOCOMP | IFF_MULTICAST; 244 sc->sc_if.if_type = IFT_SLIP; 245 sc->sc_if.if_ioctl = slioctl; 246 sc->sc_if.if_output = sloutput; 247 sc->sc_if.if_dlt = DLT_SLIP; 248 sc->sc_fastq.ifq_maxlen = 32; 249 IFQ_SET_READY(&sc->sc_if.if_snd); 250 if_attach(&sc->sc_if); 251 if_alloc_sadl(&sc->sc_if); 252 #if NBPFILTER > 0 253 bpfattach(&sc->sc_if, DLT_SLIP, SLIP_HDRLEN); 254 #endif 255 LIST_INSERT_HEAD(&sl_softc_list, sc, sc_iflist); 256 return 0; 257 } 258 259 static int 260 sl_clone_destroy(struct ifnet *ifp) 261 { 262 struct sl_softc *sc = (struct sl_softc *)ifp->if_softc; 263 264 if (sc->sc_ttyp != NULL) 265 return EBUSY; /* Not removing it */ 266 267 LIST_REMOVE(sc, sc_iflist); 268 269 #if NBPFILTER > 0 270 bpfdetach(ifp); 271 #endif 272 if_detach(ifp); 273 274 FREE(sc, M_DEVBUF); 275 return 0; 276 } 277 278 static int 279 slinit(struct sl_softc *sc) 280 { 281 282 if (sc->sc_mbuf == NULL) { 283 sc->sc_mbuf = m_gethdr(M_WAIT, MT_DATA); 284 m_clget(sc->sc_mbuf, M_WAIT); 285 } 286 sc->sc_ep = (u_char *)sc->sc_mbuf->m_ext.ext_buf + 287 sc->sc_mbuf->m_ext.ext_size; 288 sc->sc_mp = sc->sc_pktstart = (u_char *)sc->sc_mbuf->m_ext.ext_buf + 289 BUFOFFSET; 290 291 #ifdef INET 292 sl_compress_init(&sc->sc_comp); 293 #endif 294 295 return 1; 296 } 297 298 /* 299 * Line specific open routine. 300 * Attach the given tty to the first available sl unit. 301 */ 302 /* ARGSUSED */ 303 static int 304 slopen(dev_t dev __unused, struct tty *tp) 305 { 306 struct lwp *l = curlwp; /* XXX */ 307 struct sl_softc *sc; 308 int error; 309 int s; 310 311 if ((error = kauth_authorize_generic(l->l_cred, KAUTH_GENERIC_ISSUSER, 312 &l->l_acflag)) != 0) 313 return error; 314 315 if (tp->t_linesw == &slip_disc) 316 return 0; 317 318 LIST_FOREACH(sc, &sl_softc_list, sc_iflist) 319 if (sc->sc_ttyp == NULL) { 320 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 321 sc->sc_si = softintr_establish(IPL_SOFTNET, 322 slintr, sc); 323 if (sc->sc_si == NULL) 324 return ENOMEM; 325 #endif 326 if (slinit(sc) == 0) { 327 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 328 softintr_disestablish(sc->sc_si); 329 #endif 330 return ENOBUFS; 331 } 332 tp->t_sc = (caddr_t)sc; 333 sc->sc_ttyp = tp; 334 sc->sc_if.if_baudrate = tp->t_ospeed; 335 s = spltty(); 336 tp->t_state |= TS_ISOPEN | TS_XCLUDE; 337 splx(s); 338 ttyflush(tp, FREAD | FWRITE); 339 #ifdef __NetBSD__ 340 /* 341 * make sure tty output queue is large enough 342 * to hold a full-sized packet (including frame 343 * end, and a possible extra frame end). full-sized 344 * packet occupies a max of 2*SLMAX bytes (because 345 * of possible escapes), and add two on for frame 346 * ends. 347 */ 348 s = spltty(); 349 if (tp->t_outq.c_cn < 2 * SLMAX + 2) { 350 sc->sc_oldbufsize = tp->t_outq.c_cn; 351 sc->sc_oldbufquot = tp->t_outq.c_cq != 0; 352 353 clfree(&tp->t_outq); 354 error = clalloc(&tp->t_outq, 2 * SLMAX + 2, 0); 355 if (error) { 356 splx(s); 357 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 358 softintr_disestablish(sc->sc_si); 359 #endif 360 /* 361 * clalloc() might return -1 which 362 * is no good, so we need to return 363 * something else. 364 */ 365 return ENOMEM; /* XXX ?! */ 366 } 367 } else 368 sc->sc_oldbufsize = sc->sc_oldbufquot = 0; 369 splx(s); 370 #endif /* __NetBSD__ */ 371 return 0; 372 } 373 return ENXIO; 374 } 375 376 /* 377 * Line specific close routine. 378 * Detach the tty from the sl unit. 379 */ 380 static int 381 slclose(struct tty *tp, int flag __unused) 382 { 383 struct sl_softc *sc; 384 int s; 385 386 ttywflush(tp); 387 sc = tp->t_sc; 388 389 if (sc != NULL) { 390 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 391 softintr_disestablish(sc->sc_si); 392 #endif 393 s = splnet(); 394 if_down(&sc->sc_if); 395 IF_PURGE(&sc->sc_fastq); 396 splx(s); 397 398 s = spltty(); 399 ttyldisc_release(tp->t_linesw); 400 tp->t_linesw = ttyldisc_default(); 401 tp->t_state = 0; 402 403 sc->sc_ttyp = NULL; 404 tp->t_sc = NULL; 405 406 m_freem(sc->sc_mbuf); 407 sc->sc_mbuf = NULL; 408 sc->sc_ep = sc->sc_mp = sc->sc_pktstart = NULL; 409 IF_PURGE(&sc->sc_inq); 410 411 /* 412 * If necessary, install a new outq buffer of the 413 * appropriate size. 414 */ 415 if (sc->sc_oldbufsize != 0) { 416 clfree(&tp->t_outq); 417 clalloc(&tp->t_outq, sc->sc_oldbufsize, 418 sc->sc_oldbufquot); 419 } 420 splx(s); 421 } 422 423 return 0; 424 } 425 426 /* 427 * Line specific (tty) ioctl routine. 428 * Provide a way to get the sl unit number. 429 */ 430 /* ARGSUSED */ 431 static int 432 sltioctl(struct tty *tp, u_long cmd, caddr_t data, int flag __unused, 433 struct lwp *l __unused) 434 { 435 struct sl_softc *sc = (struct sl_softc *)tp->t_sc; 436 437 switch (cmd) { 438 case SLIOCGUNIT: 439 *(int *)data = sc->sc_unit; /* XXX */ 440 break; 441 442 default: 443 return EPASSTHROUGH; 444 } 445 return 0; 446 } 447 448 /* 449 * Queue a packet. Start transmission if not active. 450 * Compression happens in slintr(); if we do it here, IP TOS 451 * will cause us to not compress "background" packets, because 452 * ordering gets trashed. It can be done for all packets in slintr(). 453 */ 454 static int 455 sloutput(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst, 456 struct rtentry *rtp __unused) 457 { 458 struct sl_softc *sc = ifp->if_softc; 459 struct ip *ip; 460 struct ifqueue *ifq = NULL; 461 int s, error; 462 ALTQ_DECL(struct altq_pktattr pktattr;) 463 464 IFQ_CLASSIFY(&ifp->if_snd, m, dst->sa_family, &pktattr); 465 466 /* 467 * `Cannot happen' (see slioctl). Someday we will extend 468 * the line protocol to support other address families. 469 */ 470 if (dst->sa_family != AF_INET) { 471 printf("%s: af%d not supported\n", sc->sc_if.if_xname, 472 dst->sa_family); 473 m_freem(m); 474 sc->sc_if.if_noproto++; 475 return EAFNOSUPPORT; 476 } 477 478 if (sc->sc_ttyp == NULL) { 479 m_freem(m); 480 return ENETDOWN; /* sort of */ 481 } 482 if ((sc->sc_ttyp->t_state & TS_CARR_ON) == 0 && 483 (sc->sc_ttyp->t_cflag & CLOCAL) == 0) { 484 m_freem(m); 485 printf("%s: no carrier and not local\n", sc->sc_if.if_xname); 486 return EHOSTUNREACH; 487 } 488 ip = mtod(m, struct ip *); 489 #ifdef INET 490 if (sc->sc_if.if_flags & SC_NOICMP && ip->ip_p == IPPROTO_ICMP) { 491 m_freem(m); 492 return ENETRESET; /* XXX ? */ 493 } 494 #endif 495 496 s = spltty(); 497 if (sc->sc_oqlen && sc->sc_ttyp->t_outq.c_cc == sc->sc_oqlen) { 498 struct bintime bt; 499 500 /* if output's been stalled for too long, and restart */ 501 getbinuptime(&bt); 502 bintime_sub(&bt, &sc->sc_lastpacket); 503 if (bt.sec > 0) { 504 sc->sc_otimeout++; 505 slstart(sc->sc_ttyp); 506 } 507 } 508 splx(s); 509 510 s = splnet(); 511 #ifdef INET 512 if ((ip->ip_tos & IPTOS_LOWDELAY) != 0) 513 ifq = &sc->sc_fastq; 514 #endif 515 if ((error = ifq_enqueue2(ifp, ifq, m ALTQ_COMMA 516 ALTQ_DECL(&pktattr))) != 0) { 517 splx(s); 518 return error; 519 } 520 getbinuptime(&sc->sc_lastpacket); 521 splx(s); 522 523 s = spltty(); 524 if ((sc->sc_oqlen = sc->sc_ttyp->t_outq.c_cc) == 0) 525 slstart(sc->sc_ttyp); 526 splx(s); 527 528 return 0; 529 } 530 531 /* 532 * Start output on interface. Get another datagram 533 * to send from the interface queue and map it to 534 * the interface before starting output. 535 */ 536 static int 537 slstart(struct tty *tp) 538 { 539 struct sl_softc *sc = tp->t_sc; 540 541 /* 542 * If there is more in the output queue, just send it now. 543 * We are being called in lieu of ttstart and must do what 544 * it would. 545 */ 546 if (tp->t_outq.c_cc != 0) { 547 (*tp->t_oproc)(tp); 548 if (tp->t_outq.c_cc > SLIP_HIWAT) 549 return 0; 550 } 551 552 /* 553 * This happens briefly when the line shuts down. 554 */ 555 if (sc == NULL) 556 return 0; 557 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 558 softintr_schedule(sc->sc_si); 559 #else 560 { 561 int s = splhigh(); 562 schednetisr(NETISR_SLIP); 563 splx(s); 564 } 565 #endif 566 return 0; 567 } 568 569 /* 570 * Copy data buffer to mbuf chain; add ifnet pointer. 571 */ 572 static struct mbuf * 573 sl_btom(struct sl_softc *sc, int len) 574 { 575 struct mbuf *m; 576 577 /* 578 * Allocate a new input buffer and swap. 579 */ 580 m = sc->sc_mbuf; 581 MGETHDR(sc->sc_mbuf, M_DONTWAIT, MT_DATA); 582 if (sc->sc_mbuf == NULL) { 583 sc->sc_mbuf = m; 584 return NULL; 585 } 586 MCLGET(sc->sc_mbuf, M_DONTWAIT); 587 if ((sc->sc_mbuf->m_flags & M_EXT) == 0) { 588 m_freem(sc->sc_mbuf); 589 sc->sc_mbuf = m; 590 return NULL; 591 } 592 sc->sc_ep = (u_char *)sc->sc_mbuf->m_ext.ext_buf + 593 sc->sc_mbuf->m_ext.ext_size; 594 595 m->m_data = sc->sc_pktstart; 596 597 m->m_pkthdr.len = m->m_len = len; 598 m->m_pkthdr.rcvif = &sc->sc_if; 599 return m; 600 } 601 602 /* 603 * tty interface receiver interrupt. 604 */ 605 static int 606 slinput(int c, struct tty *tp) 607 { 608 struct sl_softc *sc; 609 struct mbuf *m; 610 int len; 611 612 tk_nin++; 613 sc = (struct sl_softc *)tp->t_sc; 614 if (sc == NULL) 615 return 0; 616 if ((c & TTY_ERRORMASK) || ((tp->t_state & TS_CARR_ON) == 0 && 617 (tp->t_cflag & CLOCAL) == 0)) { 618 sc->sc_flags |= SC_ERROR; 619 return 0; 620 } 621 c &= TTY_CHARMASK; 622 623 ++sc->sc_if.if_ibytes; 624 625 if (sc->sc_if.if_flags & IFF_DEBUG) { 626 if (c == ABT_ESC) { 627 /* 628 * If we have a previous abort, see whether 629 * this one is within the time limit. 630 */ 631 if (sc->sc_abortcount && 632 time_second >= sc->sc_starttime + ABT_WINDOW) 633 sc->sc_abortcount = 0; 634 /* 635 * If we see an abort after "idle" time, count it; 636 * record when the first abort escape arrived. 637 */ 638 if (time_second >= sc->sc_lasttime + ABT_IDLE) { 639 if (++sc->sc_abortcount == 1) 640 sc->sc_starttime = time_second; 641 if (sc->sc_abortcount >= ABT_COUNT) { 642 slclose(tp, 0); 643 return 0; 644 } 645 } 646 } else 647 sc->sc_abortcount = 0; 648 sc->sc_lasttime = time_second; 649 } 650 651 switch (c) { 652 653 case TRANS_FRAME_ESCAPE: 654 if (sc->sc_escape) 655 c = FRAME_ESCAPE; 656 break; 657 658 case TRANS_FRAME_END: 659 if (sc->sc_escape) 660 c = FRAME_END; 661 break; 662 663 case FRAME_ESCAPE: 664 sc->sc_escape = 1; 665 return 0; 666 667 case FRAME_END: 668 if (sc->sc_flags & SC_ERROR) { 669 sc->sc_flags &= ~SC_ERROR; 670 goto newpack; 671 } 672 len = sc->sc_mp - sc->sc_pktstart; 673 if (len < 3) 674 /* less than min length packet - ignore */ 675 goto newpack; 676 677 m = sl_btom(sc, len); 678 if (m == NULL) 679 goto error; 680 681 IF_ENQUEUE(&sc->sc_inq, m); 682 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 683 softintr_schedule(sc->sc_si); 684 #else 685 { 686 int s = splhigh(); 687 schednetisr(NETISR_SLIP); 688 splx(s); 689 } 690 #endif 691 goto newpack; 692 } 693 if (sc->sc_mp < sc->sc_ep) { 694 *sc->sc_mp++ = c; 695 sc->sc_escape = 0; 696 return 0; 697 } 698 699 /* can't put lower; would miss an extra frame */ 700 sc->sc_flags |= SC_ERROR; 701 702 error: 703 sc->sc_if.if_ierrors++; 704 newpack: 705 sc->sc_mp = sc->sc_pktstart = (u_char *)sc->sc_mbuf->m_ext.ext_buf + 706 BUFOFFSET; 707 sc->sc_escape = 0; 708 709 return 0; 710 } 711 712 #ifndef __HAVE_GENERIC_SOFT_INTERRUPTS 713 void 714 slnetisr(void) 715 { 716 struct sl_softc *sc; 717 718 LIST_FOREACH(sc, &sl_softc_list, sc_iflist) { 719 if (sc->sc_ttyp == NULL) 720 continue; 721 slintr(sc); 722 } 723 } 724 #endif 725 726 static void 727 slintr(void *arg) 728 { 729 struct sl_softc *sc = arg; 730 struct tty *tp = sc->sc_ttyp; 731 struct mbuf *m; 732 int s, len; 733 u_char *pktstart; 734 #ifdef INET 735 u_char c; 736 #endif 737 #if NBPFILTER > 0 738 u_char chdr[CHDR_LEN]; 739 #endif 740 741 KASSERT(tp != NULL); 742 743 /* 744 * Output processing loop. 745 */ 746 for (;;) { 747 #ifdef INET 748 struct ip *ip; 749 #endif 750 struct mbuf *m2; 751 #if NBPFILTER > 0 752 struct mbuf *bpf_m; 753 #endif 754 755 /* 756 * Do not remove the packet from the queue if it 757 * doesn't look like it will fit into the current 758 * serial output queue. With a packet full of 759 * escapes, this could be as bad as MTU*2+2. 760 */ 761 s = spltty(); 762 if (tp->t_outq.c_cn - tp->t_outq.c_cc < 763 2 * sc->sc_if.if_mtu + 2) { 764 splx(s); 765 break; 766 } 767 splx(s); 768 769 /* 770 * Get a packet and send it to the interface. 771 */ 772 s = splnet(); 773 IF_DEQUEUE(&sc->sc_fastq, m); 774 if (m) 775 sc->sc_if.if_omcasts++; /* XXX */ 776 else 777 IFQ_DEQUEUE(&sc->sc_if.if_snd, m); 778 splx(s); 779 780 if (m == NULL) 781 break; 782 783 /* 784 * We do the header compression here rather than in 785 * sloutput() because the packets will be out of order 786 * if we are using TOS queueing, and the connection 787 * ID compression will get munged when this happens. 788 */ 789 #if NBPFILTER > 0 790 if (sc->sc_if.if_bpf) { 791 /* 792 * We need to save the TCP/IP header before 793 * it's compressed. To avoid complicated 794 * code, we just make a deep copy of the 795 * entire packet (since this is a serial 796 * line, packets should be short and/or the 797 * copy should be negligible cost compared 798 * to the packet transmission time). 799 */ 800 bpf_m = m_dup(m, 0, M_COPYALL, M_DONTWAIT); 801 } else 802 bpf_m = NULL; 803 #endif 804 #ifdef INET 805 if ((ip = mtod(m, struct ip *))->ip_p == IPPROTO_TCP) { 806 if (sc->sc_if.if_flags & SC_COMPRESS) 807 *mtod(m, u_char *) |= 808 sl_compress_tcp(m, ip, &sc->sc_comp, 1); 809 } 810 #endif 811 #if NBPFILTER > 0 812 if (sc->sc_if.if_bpf && bpf_m != NULL) 813 bpf_mtap_sl_out(sc->sc_if.if_bpf, mtod(m, u_char *), 814 bpf_m); 815 #endif 816 getbinuptime(&sc->sc_lastpacket); 817 818 s = spltty(); 819 820 /* 821 * The extra FRAME_END will start up a new packet, 822 * and thus will flush any accumulated garbage. We 823 * do this whenever the line may have been idle for 824 * some time. 825 */ 826 if (tp->t_outq.c_cc == 0) { 827 sc->sc_if.if_obytes++; 828 (void)putc(FRAME_END, &tp->t_outq); 829 } 830 831 while (m) { 832 u_char *bp, *cp, *ep; 833 834 bp = cp = mtod(m, u_char *); 835 ep = cp + m->m_len; 836 while (cp < ep) { 837 /* 838 * Find out how many bytes in the 839 * string we can handle without 840 * doing something special. 841 */ 842 while (cp < ep) { 843 switch (*cp++) { 844 case FRAME_ESCAPE: 845 case FRAME_END: 846 cp--; 847 goto out; 848 } 849 } 850 out: 851 if (cp > bp) { 852 /* 853 * Put N characters at once 854 * into the tty output queue. 855 */ 856 if (b_to_q(bp, cp - bp, &tp->t_outq)) 857 break; 858 sc->sc_if.if_obytes += cp - bp; 859 } 860 /* 861 * If there are characters left in 862 * the mbuf, the first one must be 863 * special.. Put it out in a different 864 * form. 865 */ 866 if (cp < ep) { 867 if (putc(FRAME_ESCAPE, &tp->t_outq)) 868 break; 869 if (putc(*cp++ == FRAME_ESCAPE ? 870 TRANS_FRAME_ESCAPE : 871 TRANS_FRAME_END, 872 &tp->t_outq)) { 873 (void)unputc(&tp->t_outq); 874 break; 875 } 876 sc->sc_if.if_obytes += 2; 877 } 878 bp = cp; 879 } 880 MFREE(m, m2); 881 m = m2; 882 } 883 884 if (putc(FRAME_END, &tp->t_outq)) { 885 /* 886 * Not enough room. Remove a char to make 887 * room and end the packet normally. If 888 * you get many collisions (more than one 889 * or two a day), you probably do not have 890 * enough clists and you should increase 891 * "nclist" in param.c 892 */ 893 (void)unputc(&tp->t_outq); 894 (void)putc(FRAME_END, &tp->t_outq); 895 sc->sc_if.if_collisions++; 896 } else { 897 sc->sc_if.if_obytes++; 898 sc->sc_if.if_opackets++; 899 } 900 901 /* 902 * We now have characters in the output queue, 903 * kick the serial port. 904 */ 905 (*tp->t_oproc)(tp); 906 splx(s); 907 } 908 909 /* 910 * Input processing loop. 911 */ 912 for (;;) { 913 s = spltty(); 914 IF_DEQUEUE(&sc->sc_inq, m); 915 splx(s); 916 if (m == NULL) 917 break; 918 pktstart = mtod(m, u_char *); 919 len = m->m_pkthdr.len; 920 #if NBPFILTER > 0 921 if (sc->sc_if.if_bpf) { 922 /* 923 * Save the compressed header, so we 924 * can tack it on later. Note that we 925 * will end up copying garbage in some 926 * cases but this is okay. We remember 927 * where the buffer started so we can 928 * compute the new header length. 929 */ 930 memcpy(chdr, pktstart, CHDR_LEN); 931 } 932 #endif /* NBPFILTER > 0 */ 933 #ifdef INET 934 if ((c = (*pktstart & 0xf0)) != (IPVERSION << 4)) { 935 if (c & 0x80) 936 c = TYPE_COMPRESSED_TCP; 937 else if (c == TYPE_UNCOMPRESSED_TCP) 938 *pktstart &= 0x4f; /* XXX */ 939 /* 940 * We've got something that's not an IP 941 * packet. If compression is enabled, 942 * try to decompress it. Otherwise, if 943 * `auto-enable' compression is on and 944 * it's a reasonable packet, decompress 945 * it and then enable compression. 946 * Otherwise, drop it. 947 */ 948 if (sc->sc_if.if_flags & SC_COMPRESS) { 949 len = sl_uncompress_tcp(&pktstart, len, 950 (u_int)c, &sc->sc_comp); 951 if (len <= 0) { 952 m_freem(m); 953 continue; 954 } 955 } else if ((sc->sc_if.if_flags & SC_AUTOCOMP) && 956 c == TYPE_UNCOMPRESSED_TCP && len >= 40) { 957 len = sl_uncompress_tcp(&pktstart, len, 958 (u_int)c, &sc->sc_comp); 959 if (len <= 0) { 960 m_freem(m); 961 continue; 962 } 963 sc->sc_if.if_flags |= SC_COMPRESS; 964 } else { 965 m_freem(m); 966 continue; 967 } 968 } 969 #endif 970 m->m_data = (caddr_t) pktstart; 971 m->m_pkthdr.len = m->m_len = len; 972 #if NBPFILTER > 0 973 if (sc->sc_if.if_bpf) { 974 bpf_mtap_sl_in(sc->sc_if.if_bpf, chdr, &m); 975 if (m == NULL) 976 continue; 977 } 978 #endif /* NBPFILTER > 0 */ 979 /* 980 * If the packet will fit into a single 981 * header mbuf, copy it into one, to save 982 * memory. 983 */ 984 if (m->m_pkthdr.len < MHLEN) { 985 struct mbuf *n; 986 int pktlen; 987 988 MGETHDR(n, M_DONTWAIT, MT_DATA); 989 pktlen = m->m_pkthdr.len; 990 M_MOVE_PKTHDR(n, m); 991 memcpy(mtod(n, caddr_t), mtod(m, caddr_t), pktlen); 992 n->m_len = m->m_len; 993 m_freem(m); 994 m = n; 995 } 996 997 sc->sc_if.if_ipackets++; 998 getbinuptime(&sc->sc_lastpacket); 999 1000 #ifdef INET 1001 s = splnet(); 1002 if (IF_QFULL(&ipintrq)) { 1003 IF_DROP(&ipintrq); 1004 sc->sc_if.if_ierrors++; 1005 sc->sc_if.if_iqdrops++; 1006 m_freem(m); 1007 } else { 1008 IF_ENQUEUE(&ipintrq, m); 1009 schednetisr(NETISR_IP); 1010 } 1011 splx(s); 1012 #endif 1013 } 1014 } 1015 1016 /* 1017 * Process an ioctl request. 1018 */ 1019 static int 1020 slioctl(struct ifnet *ifp, u_long cmd, caddr_t data) 1021 { 1022 struct ifaddr *ifa = (struct ifaddr *)data; 1023 struct ifreq *ifr = (struct ifreq *)data; 1024 int s = splnet(), error = 0; 1025 struct sl_softc *sc = ifp->if_softc; 1026 struct ppp_stats *psp; 1027 struct ppp_comp_stats *pcp; 1028 1029 switch (cmd) { 1030 1031 case SIOCSIFADDR: 1032 if (ifa->ifa_addr->sa_family == AF_INET) 1033 ifp->if_flags |= IFF_UP; 1034 else 1035 error = EAFNOSUPPORT; 1036 break; 1037 1038 case SIOCSIFDSTADDR: 1039 if (ifa->ifa_addr->sa_family != AF_INET) 1040 error = EAFNOSUPPORT; 1041 break; 1042 1043 case SIOCSIFMTU: 1044 if ((ifr->ifr_mtu < 3) || (ifr->ifr_mtu > SLMAX)) { 1045 error = EINVAL; 1046 break; 1047 } 1048 sc->sc_if.if_mtu = ifr->ifr_mtu; 1049 break; 1050 1051 case SIOCGIFMTU: 1052 ifr->ifr_mtu = sc->sc_if.if_mtu; 1053 break; 1054 1055 case SIOCADDMULTI: 1056 case SIOCDELMULTI: 1057 if (ifr == 0) { 1058 error = EAFNOSUPPORT; /* XXX */ 1059 break; 1060 } 1061 switch (ifr->ifr_addr.sa_family) { 1062 1063 #ifdef INET 1064 case AF_INET: 1065 break; 1066 #endif 1067 1068 default: 1069 error = EAFNOSUPPORT; 1070 break; 1071 } 1072 break; 1073 1074 case SIOCGPPPSTATS: 1075 psp = &((struct ifpppstatsreq *) data)->stats; 1076 (void)memset(psp, 0, sizeof(*psp)); 1077 psp->p.ppp_ibytes = sc->sc_if.if_ibytes; 1078 psp->p.ppp_ipackets = sc->sc_if.if_ipackets; 1079 psp->p.ppp_ierrors = sc->sc_if.if_ierrors; 1080 psp->p.ppp_obytes = sc->sc_if.if_obytes; 1081 psp->p.ppp_opackets = sc->sc_if.if_opackets; 1082 psp->p.ppp_oerrors = sc->sc_if.if_oerrors; 1083 #ifdef INET 1084 psp->vj.vjs_packets = sc->sc_comp.sls_packets; 1085 psp->vj.vjs_compressed = sc->sc_comp.sls_compressed; 1086 psp->vj.vjs_searches = sc->sc_comp.sls_searches; 1087 psp->vj.vjs_misses = sc->sc_comp.sls_misses; 1088 psp->vj.vjs_uncompressedin = sc->sc_comp.sls_uncompressedin; 1089 psp->vj.vjs_compressedin = sc->sc_comp.sls_compressedin; 1090 psp->vj.vjs_errorin = sc->sc_comp.sls_errorin; 1091 psp->vj.vjs_tossed = sc->sc_comp.sls_tossed; 1092 #endif 1093 break; 1094 1095 case SIOCGPPPCSTATS: 1096 pcp = &((struct ifpppcstatsreq *) data)->stats; 1097 (void)memset(pcp, 0, sizeof(*pcp)); 1098 break; 1099 1100 default: 1101 error = EINVAL; 1102 } 1103 splx(s); 1104 return error; 1105 } 1106