if_sl.c revision 1.99
1 /* $NetBSD: if_sl.c,v 1.99 2006/07/08 18:32:53 tsutsui 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 1.99 2006/07/08 18:32:53 tsutsui 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, struct tty *tp) 305 { 306 struct proc *p = curproc; /* XXX */ 307 struct sl_softc *sc; 308 int error; 309 int s; 310 311 if ((error = kauth_authorize_generic(p->p_cred, KAUTH_GENERIC_ISSUSER, 312 &p->p_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) 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, struct lwp *l) 433 { 434 struct sl_softc *sc = (struct sl_softc *)tp->t_sc; 435 436 switch (cmd) { 437 case SLIOCGUNIT: 438 *(int *)data = sc->sc_unit; /* XXX */ 439 break; 440 441 default: 442 return EPASSTHROUGH; 443 } 444 return 0; 445 } 446 447 /* 448 * Queue a packet. Start transmission if not active. 449 * Compression happens in slintr(); if we do it here, IP TOS 450 * will cause us to not compress "background" packets, because 451 * ordering gets trashed. It can be done for all packets in slintr(). 452 */ 453 static int 454 sloutput(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst, 455 struct rtentry *rtp) 456 { 457 struct sl_softc *sc = ifp->if_softc; 458 struct ip *ip; 459 struct ifqueue *ifq = NULL; 460 int s, error; 461 ALTQ_DECL(struct altq_pktattr pktattr;) 462 463 IFQ_CLASSIFY(&ifp->if_snd, m, dst->sa_family, &pktattr); 464 465 /* 466 * `Cannot happen' (see slioctl). Someday we will extend 467 * the line protocol to support other address families. 468 */ 469 if (dst->sa_family != AF_INET) { 470 printf("%s: af%d not supported\n", sc->sc_if.if_xname, 471 dst->sa_family); 472 m_freem(m); 473 sc->sc_if.if_noproto++; 474 return EAFNOSUPPORT; 475 } 476 477 if (sc->sc_ttyp == NULL) { 478 m_freem(m); 479 return ENETDOWN; /* sort of */ 480 } 481 if ((sc->sc_ttyp->t_state & TS_CARR_ON) == 0 && 482 (sc->sc_ttyp->t_cflag & CLOCAL) == 0) { 483 m_freem(m); 484 printf("%s: no carrier and not local\n", sc->sc_if.if_xname); 485 return EHOSTUNREACH; 486 } 487 ip = mtod(m, struct ip *); 488 #ifdef INET 489 if (sc->sc_if.if_flags & SC_NOICMP && ip->ip_p == IPPROTO_ICMP) { 490 m_freem(m); 491 return ENETRESET; /* XXX ? */ 492 } 493 #endif 494 495 s = spltty(); 496 if (sc->sc_oqlen && sc->sc_ttyp->t_outq.c_cc == sc->sc_oqlen) { 497 struct bintime bt; 498 499 /* if output's been stalled for too long, and restart */ 500 getbinuptime(&bt); 501 bintime_sub(&bt, &sc->sc_lastpacket); 502 if (bt.sec > 0) { 503 sc->sc_otimeout++; 504 slstart(sc->sc_ttyp); 505 } 506 } 507 splx(s); 508 509 s = splnet(); 510 #ifdef INET 511 if ((ip->ip_tos & IPTOS_LOWDELAY) != 0) 512 ifq = &sc->sc_fastq; 513 #endif 514 if ((error = ifq_enqueue2(ifp, ifq, m ALTQ_COMMA 515 ALTQ_DECL(&pktattr))) != 0) { 516 splx(s); 517 return error; 518 } 519 getbinuptime(&sc->sc_lastpacket); 520 splx(s); 521 522 s = spltty(); 523 if ((sc->sc_oqlen = sc->sc_ttyp->t_outq.c_cc) == 0) 524 slstart(sc->sc_ttyp); 525 splx(s); 526 527 return 0; 528 } 529 530 /* 531 * Start output on interface. Get another datagram 532 * to send from the interface queue and map it to 533 * the interface before starting output. 534 */ 535 static int 536 slstart(struct tty *tp) 537 { 538 struct sl_softc *sc = tp->t_sc; 539 540 /* 541 * If there is more in the output queue, just send it now. 542 * We are being called in lieu of ttstart and must do what 543 * it would. 544 */ 545 if (tp->t_outq.c_cc != 0) { 546 (*tp->t_oproc)(tp); 547 if (tp->t_outq.c_cc > SLIP_HIWAT) 548 return 0; 549 } 550 551 /* 552 * This happens briefly when the line shuts down. 553 */ 554 if (sc == NULL) 555 return 0; 556 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 557 softintr_schedule(sc->sc_si); 558 #else 559 { 560 int s = splhigh(); 561 schednetisr(NETISR_SLIP); 562 splx(s); 563 } 564 #endif 565 return 0; 566 } 567 568 /* 569 * Copy data buffer to mbuf chain; add ifnet pointer. 570 */ 571 static struct mbuf * 572 sl_btom(struct sl_softc *sc, int len) 573 { 574 struct mbuf *m; 575 576 /* 577 * Allocate a new input buffer and swap. 578 */ 579 m = sc->sc_mbuf; 580 MGETHDR(sc->sc_mbuf, M_DONTWAIT, MT_DATA); 581 if (sc->sc_mbuf == NULL) { 582 sc->sc_mbuf = m; 583 return NULL; 584 } 585 MCLGET(sc->sc_mbuf, M_DONTWAIT); 586 if ((sc->sc_mbuf->m_flags & M_EXT) == 0) { 587 m_freem(sc->sc_mbuf); 588 sc->sc_mbuf = m; 589 return NULL; 590 } 591 sc->sc_ep = (u_char *)sc->sc_mbuf->m_ext.ext_buf + 592 sc->sc_mbuf->m_ext.ext_size; 593 594 m->m_data = sc->sc_pktstart; 595 596 m->m_pkthdr.len = m->m_len = len; 597 m->m_pkthdr.rcvif = &sc->sc_if; 598 return m; 599 } 600 601 /* 602 * tty interface receiver interrupt. 603 */ 604 static int 605 slinput(int c, struct tty *tp) 606 { 607 struct sl_softc *sc; 608 struct mbuf *m; 609 int len; 610 611 tk_nin++; 612 sc = (struct sl_softc *)tp->t_sc; 613 if (sc == NULL) 614 return 0; 615 if ((c & TTY_ERRORMASK) || ((tp->t_state & TS_CARR_ON) == 0 && 616 (tp->t_cflag & CLOCAL) == 0)) { 617 sc->sc_flags |= SC_ERROR; 618 return 0; 619 } 620 c &= TTY_CHARMASK; 621 622 ++sc->sc_if.if_ibytes; 623 624 if (sc->sc_if.if_flags & IFF_DEBUG) { 625 if (c == ABT_ESC) { 626 /* 627 * If we have a previous abort, see whether 628 * this one is within the time limit. 629 */ 630 if (sc->sc_abortcount && 631 time_second >= sc->sc_starttime + ABT_WINDOW) 632 sc->sc_abortcount = 0; 633 /* 634 * If we see an abort after "idle" time, count it; 635 * record when the first abort escape arrived. 636 */ 637 if (time_second >= sc->sc_lasttime + ABT_IDLE) { 638 if (++sc->sc_abortcount == 1) 639 sc->sc_starttime = time_second; 640 if (sc->sc_abortcount >= ABT_COUNT) { 641 slclose(tp, 0); 642 return 0; 643 } 644 } 645 } else 646 sc->sc_abortcount = 0; 647 sc->sc_lasttime = time_second; 648 } 649 650 switch (c) { 651 652 case TRANS_FRAME_ESCAPE: 653 if (sc->sc_escape) 654 c = FRAME_ESCAPE; 655 break; 656 657 case TRANS_FRAME_END: 658 if (sc->sc_escape) 659 c = FRAME_END; 660 break; 661 662 case FRAME_ESCAPE: 663 sc->sc_escape = 1; 664 return 0; 665 666 case FRAME_END: 667 if (sc->sc_flags & SC_ERROR) { 668 sc->sc_flags &= ~SC_ERROR; 669 goto newpack; 670 } 671 len = sc->sc_mp - sc->sc_pktstart; 672 if (len < 3) 673 /* less than min length packet - ignore */ 674 goto newpack; 675 676 m = sl_btom(sc, len); 677 if (m == NULL) 678 goto error; 679 680 IF_ENQUEUE(&sc->sc_inq, m); 681 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS 682 softintr_schedule(sc->sc_si); 683 #else 684 { 685 int s = splhigh(); 686 schednetisr(NETISR_SLIP); 687 splx(s); 688 } 689 #endif 690 goto newpack; 691 } 692 if (sc->sc_mp < sc->sc_ep) { 693 *sc->sc_mp++ = c; 694 sc->sc_escape = 0; 695 return 0; 696 } 697 698 /* can't put lower; would miss an extra frame */ 699 sc->sc_flags |= SC_ERROR; 700 701 error: 702 sc->sc_if.if_ierrors++; 703 newpack: 704 sc->sc_mp = sc->sc_pktstart = (u_char *)sc->sc_mbuf->m_ext.ext_buf + 705 BUFOFFSET; 706 sc->sc_escape = 0; 707 708 return 0; 709 } 710 711 #ifndef __HAVE_GENERIC_SOFT_INTERRUPTS 712 void 713 slnetisr(void) 714 { 715 struct sl_softc *sc; 716 717 LIST_FOREACH(sc, &sl_softc_list, sc_iflist) { 718 if (sc->sc_ttyp == NULL) 719 continue; 720 slintr(sc); 721 } 722 } 723 #endif 724 725 static void 726 slintr(void *arg) 727 { 728 struct sl_softc *sc = arg; 729 struct tty *tp = sc->sc_ttyp; 730 struct mbuf *m; 731 int s, len; 732 u_char *pktstart; 733 #ifdef INET 734 u_char c; 735 #endif 736 #if NBPFILTER > 0 737 u_char chdr[CHDR_LEN]; 738 #endif 739 740 KASSERT(tp != NULL); 741 742 /* 743 * Output processing loop. 744 */ 745 for (;;) { 746 #ifdef INET 747 struct ip *ip; 748 #endif 749 struct mbuf *m2; 750 #if NBPFILTER > 0 751 struct mbuf *bpf_m; 752 #endif 753 754 /* 755 * Do not remove the packet from the queue if it 756 * doesn't look like it will fit into the current 757 * serial output queue. With a packet full of 758 * escapes, this could be as bad as MTU*2+2. 759 */ 760 s = spltty(); 761 if (tp->t_outq.c_cn - tp->t_outq.c_cc < 762 2 * sc->sc_if.if_mtu + 2) { 763 splx(s); 764 break; 765 } 766 splx(s); 767 768 /* 769 * Get a packet and send it to the interface. 770 */ 771 s = splnet(); 772 IF_DEQUEUE(&sc->sc_fastq, m); 773 if (m) 774 sc->sc_if.if_omcasts++; /* XXX */ 775 else 776 IFQ_DEQUEUE(&sc->sc_if.if_snd, m); 777 splx(s); 778 779 if (m == NULL) 780 break; 781 782 /* 783 * We do the header compression here rather than in 784 * sloutput() because the packets will be out of order 785 * if we are using TOS queueing, and the connection 786 * ID compression will get munged when this happens. 787 */ 788 #if NBPFILTER > 0 789 if (sc->sc_if.if_bpf) { 790 /* 791 * We need to save the TCP/IP header before 792 * it's compressed. To avoid complicated 793 * code, we just make a deep copy of the 794 * entire packet (since this is a serial 795 * line, packets should be short and/or the 796 * copy should be negligible cost compared 797 * to the packet transmission time). 798 */ 799 bpf_m = m_dup(m, 0, M_COPYALL, M_DONTWAIT); 800 } else 801 bpf_m = NULL; 802 #endif 803 #ifdef INET 804 if ((ip = mtod(m, struct ip *))->ip_p == IPPROTO_TCP) { 805 if (sc->sc_if.if_flags & SC_COMPRESS) 806 *mtod(m, u_char *) |= 807 sl_compress_tcp(m, ip, &sc->sc_comp, 1); 808 } 809 #endif 810 #if NBPFILTER > 0 811 if (sc->sc_if.if_bpf && bpf_m != NULL) 812 bpf_mtap_sl_out(sc->sc_if.if_bpf, mtod(m, u_char *), 813 bpf_m); 814 #endif 815 getbinuptime(&sc->sc_lastpacket); 816 817 s = spltty(); 818 819 /* 820 * The extra FRAME_END will start up a new packet, 821 * and thus will flush any accumulated garbage. We 822 * do this whenever the line may have been idle for 823 * some time. 824 */ 825 if (tp->t_outq.c_cc == 0) { 826 sc->sc_if.if_obytes++; 827 (void)putc(FRAME_END, &tp->t_outq); 828 } 829 830 while (m) { 831 u_char *bp, *cp, *ep; 832 833 bp = cp = mtod(m, u_char *); 834 ep = cp + m->m_len; 835 while (cp < ep) { 836 /* 837 * Find out how many bytes in the 838 * string we can handle without 839 * doing something special. 840 */ 841 while (cp < ep) { 842 switch (*cp++) { 843 case FRAME_ESCAPE: 844 case FRAME_END: 845 cp--; 846 goto out; 847 } 848 } 849 out: 850 if (cp > bp) { 851 /* 852 * Put N characters at once 853 * into the tty output queue. 854 */ 855 if (b_to_q(bp, cp - bp, &tp->t_outq)) 856 break; 857 sc->sc_if.if_obytes += cp - bp; 858 } 859 /* 860 * If there are characters left in 861 * the mbuf, the first one must be 862 * special.. Put it out in a different 863 * form. 864 */ 865 if (cp < ep) { 866 if (putc(FRAME_ESCAPE, &tp->t_outq)) 867 break; 868 if (putc(*cp++ == FRAME_ESCAPE ? 869 TRANS_FRAME_ESCAPE : 870 TRANS_FRAME_END, 871 &tp->t_outq)) { 872 (void)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 getbinuptime(&sc->sc_lastpacket); 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 21:09:56 GMT 2025