1 /* $NetBSD: if_sl.c,v 1.116 2010/01/19 22:08:01 pooka 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 1.116 2010/01/19 22:08:01 pooka Exp $"); 64 65 #include "opt_inet.h" 66 67 #include <sys/param.h> 68 #include <sys/proc.h> 69 #include <sys/malloc.h> 70 #include <sys/mbuf.h> 71 #include <sys/buf.h> 72 #include <sys/dkstat.h> 73 #include <sys/socket.h> 74 #include <sys/ioctl.h> 75 #include <sys/file.h> 76 #include <sys/conf.h> 77 #include <sys/tty.h> 78 #include <sys/kernel.h> 79 #include <sys/socketvar.h> 80 #if __NetBSD__ 81 #include <sys/systm.h> 82 #include <sys/kauth.h> 83 #endif 84 #include <sys/cpu.h> 85 #include <sys/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 #include <sys/time.h> 106 #include <net/bpf.h> 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 static void slintr(void *); 188 189 static int slinit(struct sl_softc *); 190 static struct mbuf *sl_btom(struct sl_softc *, int); 191 192 static int slclose(struct tty *, int); 193 static int slinput(int, struct tty *); 194 static int slioctl(struct ifnet *, u_long, void *); 195 static int slopen(dev_t, struct tty *); 196 static int sloutput(struct ifnet *, struct mbuf *, const struct sockaddr *, 197 struct rtentry *); 198 static int slstart(struct tty *); 199 static int sltioctl(struct tty *, u_long, void *, int, struct lwp *); 200 201 static struct linesw slip_disc = { 202 .l_name = "slip", 203 .l_open = slopen, 204 .l_close = slclose, 205 .l_read = ttyerrio, 206 .l_write = ttyerrio, 207 .l_ioctl = sltioctl, 208 .l_rint = slinput, 209 .l_start = slstart, 210 .l_modem = nullmodem, 211 .l_poll = ttyerrpoll 212 }; 213 214 void slattach(void); 215 216 void 217 slattach(void) 218 { 219 220 if (ttyldisc_attach(&slip_disc) != 0) 221 panic("slattach"); 222 LIST_INIT(&sl_softc_list); 223 if_clone_attach(&sl_cloner); 224 } 225 226 static int 227 sl_clone_create(struct if_clone *ifc, int unit) 228 { 229 struct sl_softc *sc; 230 231 sc = malloc(sizeof(*sc), M_DEVBUF, M_WAIT|M_ZERO); 232 sc->sc_unit = unit; 233 if_initname(&sc->sc_if, ifc->ifc_name, unit); 234 sc->sc_if.if_softc = sc; 235 sc->sc_if.if_mtu = SLMTU; 236 sc->sc_if.if_flags = IFF_POINTOPOINT | SC_AUTOCOMP | IFF_MULTICAST; 237 sc->sc_if.if_type = IFT_SLIP; 238 sc->sc_if.if_ioctl = slioctl; 239 sc->sc_if.if_output = sloutput; 240 sc->sc_if.if_dlt = DLT_SLIP; 241 sc->sc_fastq.ifq_maxlen = 32; 242 IFQ_SET_READY(&sc->sc_if.if_snd); 243 if_attach(&sc->sc_if); 244 if_alloc_sadl(&sc->sc_if); 245 bpf_ops->bpf_attach(&sc->sc_if, DLT_SLIP, SLIP_HDRLEN, 246 &sc->sc_if.if_bpf); 247 LIST_INSERT_HEAD(&sl_softc_list, sc, sc_iflist); 248 return 0; 249 } 250 251 static int 252 sl_clone_destroy(struct ifnet *ifp) 253 { 254 struct sl_softc *sc = (struct sl_softc *)ifp->if_softc; 255 256 if (sc->sc_ttyp != NULL) 257 return EBUSY; /* Not removing it */ 258 259 LIST_REMOVE(sc, sc_iflist); 260 261 bpf_ops->bpf_detach(ifp); 262 if_detach(ifp); 263 264 free(sc, M_DEVBUF); 265 return 0; 266 } 267 268 static int 269 slinit(struct sl_softc *sc) 270 { 271 272 if (sc->sc_mbuf == NULL) { 273 sc->sc_mbuf = m_gethdr(M_WAIT, MT_DATA); 274 m_clget(sc->sc_mbuf, M_WAIT); 275 } 276 sc->sc_ep = (u_char *)sc->sc_mbuf->m_ext.ext_buf + 277 sc->sc_mbuf->m_ext.ext_size; 278 sc->sc_mp = sc->sc_pktstart = (u_char *)sc->sc_mbuf->m_ext.ext_buf + 279 BUFOFFSET; 280 281 #ifdef INET 282 sl_compress_init(&sc->sc_comp); 283 #endif 284 285 return 1; 286 } 287 288 /* 289 * Line specific open routine. 290 * Attach the given tty to the first available sl unit. 291 */ 292 /* ARGSUSED */ 293 static int 294 slopen(dev_t dev, struct tty *tp) 295 { 296 struct lwp *l = curlwp; /* XXX */ 297 struct sl_softc *sc; 298 int error; 299 300 error = kauth_authorize_network(l->l_cred, KAUTH_NETWORK_INTERFACE_SLIP, 301 KAUTH_REQ_NETWORK_INTERFACE_SLIP_ADD, NULL, NULL, NULL); 302 if (error) 303 return error; 304 305 if (tp->t_linesw == &slip_disc) 306 return 0; 307 308 LIST_FOREACH(sc, &sl_softc_list, sc_iflist) 309 if (sc->sc_ttyp == NULL) { 310 sc->sc_si = softint_establish(SOFTINT_NET, 311 slintr, sc); 312 if (sc->sc_si == NULL) 313 return ENOMEM; 314 if (slinit(sc) == 0) { 315 softint_disestablish(sc->sc_si); 316 return ENOBUFS; 317 } 318 tp->t_sc = (void *)sc; 319 sc->sc_ttyp = tp; 320 sc->sc_if.if_baudrate = tp->t_ospeed; 321 mutex_spin_enter(&tty_lock); 322 tp->t_state |= TS_ISOPEN | TS_XCLUDE; 323 ttyflush(tp, FREAD | FWRITE); 324 /* 325 * make sure tty output queue is large enough 326 * to hold a full-sized packet (including frame 327 * end, and a possible extra frame end). full-sized 328 * packet occupies a max of 2*SLMAX bytes (because 329 * of possible escapes), and add two on for frame 330 * ends. 331 */ 332 if (tp->t_outq.c_cn < 2 * SLMAX + 2) { 333 sc->sc_oldbufsize = tp->t_outq.c_cn; 334 sc->sc_oldbufquot = tp->t_outq.c_cq != 0; 335 336 clfree(&tp->t_outq); 337 mutex_spin_exit(&tty_lock); 338 error = clalloc(&tp->t_outq, 2 * SLMAX + 2, 0); 339 if (error) { 340 softint_disestablish(sc->sc_si); 341 /* 342 * clalloc() might return -1 which 343 * is no good, so we need to return 344 * something else. 345 */ 346 return ENOMEM; /* XXX ?! */ 347 } 348 } else { 349 sc->sc_oldbufsize = sc->sc_oldbufquot = 0; 350 mutex_spin_exit(&tty_lock); 351 } 352 return 0; 353 } 354 return ENXIO; 355 } 356 357 /* 358 * Line specific close routine. 359 * Detach the tty from the sl unit. 360 */ 361 static int 362 slclose(struct tty *tp, int flag) 363 { 364 struct sl_softc *sc; 365 int s; 366 367 ttywflush(tp); 368 sc = tp->t_sc; 369 370 if (sc != NULL) { 371 softint_disestablish(sc->sc_si); 372 s = splnet(); 373 if_down(&sc->sc_if); 374 IF_PURGE(&sc->sc_fastq); 375 splx(s); 376 377 s = spltty(); 378 ttyldisc_release(tp->t_linesw); 379 tp->t_linesw = ttyldisc_default(); 380 tp->t_state = 0; 381 382 sc->sc_ttyp = NULL; 383 tp->t_sc = NULL; 384 385 m_freem(sc->sc_mbuf); 386 sc->sc_mbuf = NULL; 387 sc->sc_ep = sc->sc_mp = sc->sc_pktstart = NULL; 388 IF_PURGE(&sc->sc_inq); 389 390 /* 391 * If necessary, install a new outq buffer of the 392 * appropriate size. 393 */ 394 if (sc->sc_oldbufsize != 0) { 395 clfree(&tp->t_outq); 396 clalloc(&tp->t_outq, sc->sc_oldbufsize, 397 sc->sc_oldbufquot); 398 } 399 splx(s); 400 } 401 402 return 0; 403 } 404 405 /* 406 * Line specific (tty) ioctl routine. 407 * Provide a way to get the sl unit number. 408 */ 409 /* ARGSUSED */ 410 static int 411 sltioctl(struct tty *tp, u_long cmd, void *data, int flag, 412 struct lwp *l) 413 { 414 struct sl_softc *sc = (struct sl_softc *)tp->t_sc; 415 416 switch (cmd) { 417 case SLIOCGUNIT: 418 *(int *)data = sc->sc_unit; /* XXX */ 419 break; 420 421 default: 422 return EPASSTHROUGH; 423 } 424 return 0; 425 } 426 427 /* 428 * Queue a packet. Start transmission if not active. 429 * Compression happens in slintr(); if we do it here, IP TOS 430 * will cause us to not compress "background" packets, because 431 * ordering gets trashed. It can be done for all packets in slintr(). 432 */ 433 static int 434 sloutput(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst, 435 struct rtentry *rtp) 436 { 437 struct sl_softc *sc = ifp->if_softc; 438 struct ip *ip; 439 struct ifqueue *ifq = NULL; 440 int s, error; 441 ALTQ_DECL(struct altq_pktattr pktattr;) 442 443 IFQ_CLASSIFY(&ifp->if_snd, m, dst->sa_family, &pktattr); 444 445 /* 446 * `Cannot happen' (see slioctl). Someday we will extend 447 * the line protocol to support other address families. 448 */ 449 if (dst->sa_family != AF_INET) { 450 printf("%s: af%d not supported\n", sc->sc_if.if_xname, 451 dst->sa_family); 452 m_freem(m); 453 sc->sc_if.if_noproto++; 454 return EAFNOSUPPORT; 455 } 456 457 if (sc->sc_ttyp == NULL) { 458 m_freem(m); 459 return ENETDOWN; /* sort of */ 460 } 461 if ((sc->sc_ttyp->t_state & TS_CARR_ON) == 0 && 462 (sc->sc_ttyp->t_cflag & CLOCAL) == 0) { 463 m_freem(m); 464 printf("%s: no carrier and not local\n", sc->sc_if.if_xname); 465 return EHOSTUNREACH; 466 } 467 ip = mtod(m, struct ip *); 468 #ifdef INET 469 if (sc->sc_if.if_flags & SC_NOICMP && ip->ip_p == IPPROTO_ICMP) { 470 m_freem(m); 471 return ENETRESET; /* XXX ? */ 472 } 473 #endif 474 475 s = spltty(); 476 if (sc->sc_oqlen && sc->sc_ttyp->t_outq.c_cc == sc->sc_oqlen) { 477 struct bintime bt; 478 479 /* if output's been stalled for too long, and restart */ 480 getbinuptime(&bt); 481 bintime_sub(&bt, &sc->sc_lastpacket); 482 if (bt.sec > 0) { 483 sc->sc_otimeout++; 484 slstart(sc->sc_ttyp); 485 } 486 } 487 splx(s); 488 489 s = splnet(); 490 #ifdef INET 491 if ((ip->ip_tos & IPTOS_LOWDELAY) != 0) 492 ifq = &sc->sc_fastq; 493 #endif 494 if ((error = ifq_enqueue2(ifp, ifq, m ALTQ_COMMA 495 ALTQ_DECL(&pktattr))) != 0) { 496 splx(s); 497 return error; 498 } 499 getbinuptime(&sc->sc_lastpacket); 500 splx(s); 501 502 s = spltty(); 503 if ((sc->sc_oqlen = sc->sc_ttyp->t_outq.c_cc) == 0) 504 slstart(sc->sc_ttyp); 505 splx(s); 506 507 return 0; 508 } 509 510 /* 511 * Start output on interface. Get another datagram 512 * to send from the interface queue and map it to 513 * the interface before starting output. 514 */ 515 static int 516 slstart(struct tty *tp) 517 { 518 struct sl_softc *sc = tp->t_sc; 519 520 /* 521 * If there is more in the output queue, just send it now. 522 * We are being called in lieu of ttstart and must do what 523 * it would. 524 */ 525 if (tp->t_outq.c_cc != 0) { 526 (*tp->t_oproc)(tp); 527 if (tp->t_outq.c_cc > SLIP_HIWAT) 528 return 0; 529 } 530 531 /* 532 * This happens briefly when the line shuts down. 533 */ 534 if (sc == NULL) 535 return 0; 536 softint_schedule(sc->sc_si); 537 return 0; 538 } 539 540 /* 541 * Copy data buffer to mbuf chain; add ifnet pointer. 542 */ 543 static struct mbuf * 544 sl_btom(struct sl_softc *sc, int len) 545 { 546 struct mbuf *m; 547 548 /* 549 * Allocate a new input buffer and swap. 550 */ 551 m = sc->sc_mbuf; 552 MGETHDR(sc->sc_mbuf, M_DONTWAIT, MT_DATA); 553 if (sc->sc_mbuf == NULL) { 554 sc->sc_mbuf = m; 555 return NULL; 556 } 557 MCLGET(sc->sc_mbuf, M_DONTWAIT); 558 if ((sc->sc_mbuf->m_flags & M_EXT) == 0) { 559 m_freem(sc->sc_mbuf); 560 sc->sc_mbuf = m; 561 return NULL; 562 } 563 sc->sc_ep = (u_char *)sc->sc_mbuf->m_ext.ext_buf + 564 sc->sc_mbuf->m_ext.ext_size; 565 566 m->m_data = sc->sc_pktstart; 567 568 m->m_pkthdr.len = m->m_len = len; 569 m->m_pkthdr.rcvif = &sc->sc_if; 570 return m; 571 } 572 573 /* 574 * tty interface receiver interrupt. 575 */ 576 static int 577 slinput(int c, struct tty *tp) 578 { 579 struct sl_softc *sc; 580 struct mbuf *m; 581 int len; 582 583 tk_nin++; 584 sc = (struct sl_softc *)tp->t_sc; 585 if (sc == NULL) 586 return 0; 587 if ((c & TTY_ERRORMASK) || ((tp->t_state & TS_CARR_ON) == 0 && 588 (tp->t_cflag & CLOCAL) == 0)) { 589 sc->sc_flags |= SC_ERROR; 590 return 0; 591 } 592 c &= TTY_CHARMASK; 593 594 ++sc->sc_if.if_ibytes; 595 596 if (sc->sc_if.if_flags & IFF_DEBUG) { 597 if (c == ABT_ESC) { 598 /* 599 * If we have a previous abort, see whether 600 * this one is within the time limit. 601 */ 602 if (sc->sc_abortcount && 603 time_second >= sc->sc_starttime + ABT_WINDOW) 604 sc->sc_abortcount = 0; 605 /* 606 * If we see an abort after "idle" time, count it; 607 * record when the first abort escape arrived. 608 */ 609 if (time_second >= sc->sc_lasttime + ABT_IDLE) { 610 if (++sc->sc_abortcount == 1) 611 sc->sc_starttime = time_second; 612 if (sc->sc_abortcount >= ABT_COUNT) { 613 slclose(tp, 0); 614 return 0; 615 } 616 } 617 } else 618 sc->sc_abortcount = 0; 619 sc->sc_lasttime = time_second; 620 } 621 622 switch (c) { 623 624 case TRANS_FRAME_ESCAPE: 625 if (sc->sc_escape) 626 c = FRAME_ESCAPE; 627 break; 628 629 case TRANS_FRAME_END: 630 if (sc->sc_escape) 631 c = FRAME_END; 632 break; 633 634 case FRAME_ESCAPE: 635 sc->sc_escape = 1; 636 return 0; 637 638 case FRAME_END: 639 if (sc->sc_flags & SC_ERROR) { 640 sc->sc_flags &= ~SC_ERROR; 641 goto newpack; 642 } 643 len = sc->sc_mp - sc->sc_pktstart; 644 if (len < 3) 645 /* less than min length packet - ignore */ 646 goto newpack; 647 648 m = sl_btom(sc, len); 649 if (m == NULL) 650 goto error; 651 652 IF_ENQUEUE(&sc->sc_inq, m); 653 softint_schedule(sc->sc_si); 654 goto newpack; 655 } 656 if (sc->sc_mp < sc->sc_ep) { 657 *sc->sc_mp++ = c; 658 sc->sc_escape = 0; 659 return 0; 660 } 661 662 /* can't put lower; would miss an extra frame */ 663 sc->sc_flags |= SC_ERROR; 664 665 error: 666 sc->sc_if.if_ierrors++; 667 newpack: 668 sc->sc_mp = sc->sc_pktstart = (u_char *)sc->sc_mbuf->m_ext.ext_buf + 669 BUFOFFSET; 670 sc->sc_escape = 0; 671 672 return 0; 673 } 674 675 static void 676 slintr(void *arg) 677 { 678 struct sl_softc *sc = arg; 679 struct tty *tp = sc->sc_ttyp; 680 struct mbuf *m; 681 int s, len; 682 u_char *pktstart; 683 #ifdef INET 684 u_char c; 685 #endif 686 u_char chdr[CHDR_LEN]; 687 688 KASSERT(tp != NULL); 689 690 /* 691 * Output processing loop. 692 */ 693 mutex_enter(softnet_lock); 694 for (;;) { 695 #ifdef INET 696 struct ip *ip; 697 #endif 698 struct mbuf *m2; 699 struct mbuf *bpf_m; 700 701 /* 702 * Do not remove the packet from the queue if it 703 * doesn't look like it will fit into the current 704 * serial output queue. With a packet full of 705 * escapes, this could be as bad as MTU*2+2. 706 */ 707 s = spltty(); 708 if (tp->t_outq.c_cn - tp->t_outq.c_cc < 709 2 * sc->sc_if.if_mtu + 2) { 710 splx(s); 711 break; 712 } 713 splx(s); 714 715 /* 716 * Get a packet and send it to the interface. 717 */ 718 s = splnet(); 719 IF_DEQUEUE(&sc->sc_fastq, m); 720 if (m) 721 sc->sc_if.if_omcasts++; /* XXX */ 722 else 723 IFQ_DEQUEUE(&sc->sc_if.if_snd, m); 724 splx(s); 725 726 if (m == NULL) 727 break; 728 729 /* 730 * We do the header compression here rather than in 731 * sloutput() because the packets will be out of order 732 * if we are using TOS queueing, and the connection 733 * ID compression will get munged when this happens. 734 */ 735 if (sc->sc_if.if_bpf) { 736 /* 737 * We need to save the TCP/IP header before 738 * it's compressed. To avoid complicated 739 * code, we just make a deep copy of the 740 * entire packet (since this is a serial 741 * line, packets should be short and/or the 742 * copy should be negligible cost compared 743 * to the packet transmission time). 744 */ 745 bpf_m = m_dup(m, 0, M_COPYALL, M_DONTWAIT); 746 } else 747 bpf_m = NULL; 748 #ifdef INET 749 if ((ip = mtod(m, struct ip *))->ip_p == IPPROTO_TCP) { 750 if (sc->sc_if.if_flags & SC_COMPRESS) 751 *mtod(m, u_char *) |= 752 sl_compress_tcp(m, ip, &sc->sc_comp, 1); 753 } 754 #endif 755 if (sc->sc_if.if_bpf && bpf_m != NULL) 756 bpf_ops->bpf_mtap_sl_out(sc->sc_if.if_bpf, mtod(m, u_char *), bpf_m); 757 getbinuptime(&sc->sc_lastpacket); 758 759 s = spltty(); 760 761 /* 762 * The extra FRAME_END will start up a new packet, 763 * and thus will flush any accumulated garbage. We 764 * do this whenever the line may have been idle for 765 * some time. 766 */ 767 if (tp->t_outq.c_cc == 0) { 768 sc->sc_if.if_obytes++; 769 (void)putc(FRAME_END, &tp->t_outq); 770 } 771 772 while (m) { 773 u_char *bp, *cp, *ep; 774 775 bp = cp = mtod(m, u_char *); 776 ep = cp + m->m_len; 777 while (cp < ep) { 778 /* 779 * Find out how many bytes in the 780 * string we can handle without 781 * doing something special. 782 */ 783 while (cp < ep) { 784 switch (*cp++) { 785 case FRAME_ESCAPE: 786 case FRAME_END: 787 cp--; 788 goto out; 789 } 790 } 791 out: 792 if (cp > bp) { 793 /* 794 * Put N characters at once 795 * into the tty output queue. 796 */ 797 if (b_to_q(bp, cp - bp, &tp->t_outq)) 798 break; 799 sc->sc_if.if_obytes += cp - bp; 800 } 801 /* 802 * If there are characters left in 803 * the mbuf, the first one must be 804 * special.. Put it out in a different 805 * form. 806 */ 807 if (cp < ep) { 808 if (putc(FRAME_ESCAPE, &tp->t_outq)) 809 break; 810 if (putc(*cp++ == FRAME_ESCAPE ? 811 TRANS_FRAME_ESCAPE : 812 TRANS_FRAME_END, 813 &tp->t_outq)) { 814 (void)unputc(&tp->t_outq); 815 break; 816 } 817 sc->sc_if.if_obytes += 2; 818 } 819 bp = cp; 820 } 821 MFREE(m, m2); 822 m = m2; 823 } 824 825 if (putc(FRAME_END, &tp->t_outq)) { 826 /* 827 * Not enough room. Remove a char to make 828 * room and end the packet normally. If 829 * you get many collisions (more than one 830 * or two a day), you probably do not have 831 * enough clists and you should increase 832 * "nclist" in param.c 833 */ 834 (void)unputc(&tp->t_outq); 835 (void)putc(FRAME_END, &tp->t_outq); 836 sc->sc_if.if_collisions++; 837 } else { 838 sc->sc_if.if_obytes++; 839 sc->sc_if.if_opackets++; 840 } 841 842 /* 843 * We now have characters in the output queue, 844 * kick the serial port. 845 */ 846 (*tp->t_oproc)(tp); 847 splx(s); 848 } 849 850 /* 851 * Input processing loop. 852 */ 853 for (;;) { 854 s = spltty(); 855 IF_DEQUEUE(&sc->sc_inq, m); 856 splx(s); 857 if (m == NULL) 858 break; 859 pktstart = mtod(m, u_char *); 860 len = m->m_pkthdr.len; 861 if (sc->sc_if.if_bpf) { 862 /* 863 * Save the compressed header, so we 864 * can tack it on later. Note that we 865 * will end up copying garbage in some 866 * cases but this is okay. We remember 867 * where the buffer started so we can 868 * compute the new header length. 869 */ 870 memcpy(chdr, pktstart, CHDR_LEN); 871 } 872 #ifdef INET 873 if ((c = (*pktstart & 0xf0)) != (IPVERSION << 4)) { 874 if (c & 0x80) 875 c = TYPE_COMPRESSED_TCP; 876 else if (c == TYPE_UNCOMPRESSED_TCP) 877 *pktstart &= 0x4f; /* XXX */ 878 /* 879 * We've got something that's not an IP 880 * packet. If compression is enabled, 881 * try to decompress it. Otherwise, if 882 * `auto-enable' compression is on and 883 * it's a reasonable packet, decompress 884 * it and then enable compression. 885 * Otherwise, drop it. 886 */ 887 if (sc->sc_if.if_flags & SC_COMPRESS) { 888 len = sl_uncompress_tcp(&pktstart, len, 889 (u_int)c, &sc->sc_comp); 890 if (len <= 0) { 891 m_freem(m); 892 continue; 893 } 894 } else if ((sc->sc_if.if_flags & SC_AUTOCOMP) && 895 c == TYPE_UNCOMPRESSED_TCP && len >= 40) { 896 len = sl_uncompress_tcp(&pktstart, len, 897 (u_int)c, &sc->sc_comp); 898 if (len <= 0) { 899 m_freem(m); 900 continue; 901 } 902 sc->sc_if.if_flags |= SC_COMPRESS; 903 } else { 904 m_freem(m); 905 continue; 906 } 907 } 908 #endif 909 m->m_data = (void *) pktstart; 910 m->m_pkthdr.len = m->m_len = len; 911 if (sc->sc_if.if_bpf) { 912 bpf_ops->bpf_mtap_sl_in(sc->sc_if.if_bpf, chdr, &m); 913 if (m == NULL) 914 continue; 915 } 916 /* 917 * If the packet will fit into a single 918 * header mbuf, copy it into one, to save 919 * memory. 920 */ 921 if (m->m_pkthdr.len < MHLEN) { 922 struct mbuf *n; 923 int pktlen; 924 925 MGETHDR(n, M_DONTWAIT, MT_DATA); 926 pktlen = m->m_pkthdr.len; 927 M_MOVE_PKTHDR(n, m); 928 memcpy(mtod(n, void *), mtod(m, void *), pktlen); 929 n->m_len = m->m_len; 930 m_freem(m); 931 m = n; 932 } 933 934 sc->sc_if.if_ipackets++; 935 getbinuptime(&sc->sc_lastpacket); 936 937 #ifdef INET 938 s = splnet(); 939 if (IF_QFULL(&ipintrq)) { 940 IF_DROP(&ipintrq); 941 sc->sc_if.if_ierrors++; 942 sc->sc_if.if_iqdrops++; 943 m_freem(m); 944 } else { 945 IF_ENQUEUE(&ipintrq, m); 946 schednetisr(NETISR_IP); 947 } 948 splx(s); 949 #endif 950 } 951 mutex_exit(softnet_lock); 952 } 953 954 /* 955 * Process an ioctl request. 956 */ 957 static int 958 slioctl(struct ifnet *ifp, u_long cmd, void *data) 959 { 960 struct ifaddr *ifa = (struct ifaddr *)data; 961 struct ifreq *ifr = (struct ifreq *)data; 962 int s = splnet(), error = 0; 963 struct sl_softc *sc = ifp->if_softc; 964 struct ppp_stats *psp; 965 struct ppp_comp_stats *pcp; 966 967 switch (cmd) { 968 969 case SIOCINITIFADDR: 970 if (ifa->ifa_addr->sa_family == AF_INET) 971 ifp->if_flags |= IFF_UP; 972 else 973 error = EAFNOSUPPORT; 974 break; 975 976 case SIOCSIFDSTADDR: 977 if (ifa->ifa_addr->sa_family != AF_INET) 978 error = EAFNOSUPPORT; 979 break; 980 981 case SIOCSIFMTU: 982 if ((ifr->ifr_mtu < 3) || (ifr->ifr_mtu > SLMAX)) { 983 error = EINVAL; 984 break; 985 } 986 /*FALLTHROUGH*/ 987 case SIOCGIFMTU: 988 if ((error = ifioctl_common(&sc->sc_if, cmd, data)) == ENETRESET) 989 error = 0; 990 break; 991 992 case SIOCADDMULTI: 993 case SIOCDELMULTI: 994 if (ifr == 0) { 995 error = EAFNOSUPPORT; /* XXX */ 996 break; 997 } 998 switch (ifreq_getaddr(cmd, ifr)->sa_family) { 999 1000 #ifdef INET 1001 case AF_INET: 1002 break; 1003 #endif 1004 1005 default: 1006 error = EAFNOSUPPORT; 1007 break; 1008 } 1009 break; 1010 1011 case SIOCGPPPSTATS: 1012 psp = &((struct ifpppstatsreq *) data)->stats; 1013 (void)memset(psp, 0, sizeof(*psp)); 1014 psp->p.ppp_ibytes = sc->sc_if.if_ibytes; 1015 psp->p.ppp_ipackets = sc->sc_if.if_ipackets; 1016 psp->p.ppp_ierrors = sc->sc_if.if_ierrors; 1017 psp->p.ppp_obytes = sc->sc_if.if_obytes; 1018 psp->p.ppp_opackets = sc->sc_if.if_opackets; 1019 psp->p.ppp_oerrors = sc->sc_if.if_oerrors; 1020 #ifdef INET 1021 psp->vj.vjs_packets = sc->sc_comp.sls_packets; 1022 psp->vj.vjs_compressed = sc->sc_comp.sls_compressed; 1023 psp->vj.vjs_searches = sc->sc_comp.sls_searches; 1024 psp->vj.vjs_misses = sc->sc_comp.sls_misses; 1025 psp->vj.vjs_uncompressedin = sc->sc_comp.sls_uncompressedin; 1026 psp->vj.vjs_compressedin = sc->sc_comp.sls_compressedin; 1027 psp->vj.vjs_errorin = sc->sc_comp.sls_errorin; 1028 psp->vj.vjs_tossed = sc->sc_comp.sls_tossed; 1029 #endif 1030 break; 1031 1032 case SIOCGPPPCSTATS: 1033 pcp = &((struct ifpppcstatsreq *) data)->stats; 1034 (void)memset(pcp, 0, sizeof(*pcp)); 1035 break; 1036 1037 default: 1038 error = ifioctl_common(ifp, cmd, data); 1039 break; 1040 } 1041 splx(s); 1042 return error; 1043 } 1044