Annotation of sys/net/if_sl.c, Revision 1.1
1.1 ! nbrk 1: /* $OpenBSD: if_sl.c,v 1.32 2006/03/25 22:41:47 djm Exp $ */
! 2: /* $NetBSD: if_sl.c,v 1.39.4.1 1996/06/02 16:26:31 thorpej Exp $ */
! 3:
! 4: /*
! 5: * Copyright (c) 1987, 1989, 1992, 1993
! 6: * The Regents of the University of California. All rights reserved.
! 7: *
! 8: * Redistribution and use in source and binary forms, with or without
! 9: * modification, are permitted provided that the following conditions
! 10: * are met:
! 11: * 1. Redistributions of source code must retain the above copyright
! 12: * notice, this list of conditions and the following disclaimer.
! 13: * 2. Redistributions in binary form must reproduce the above copyright
! 14: * notice, this list of conditions and the following disclaimer in the
! 15: * documentation and/or other materials provided with the distribution.
! 16: * 3. Neither the name of the University nor the names of its contributors
! 17: * may be used to endorse or promote products derived from this software
! 18: * without specific prior written permission.
! 19: *
! 20: * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
! 21: * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
! 22: * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
! 23: * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
! 24: * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
! 25: * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
! 26: * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
! 27: * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
! 28: * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
! 29: * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
! 30: * SUCH DAMAGE.
! 31: *
! 32: * @(#)if_sl.c 8.6 (Berkeley) 2/1/94
! 33: */
! 34:
! 35: /*
! 36: * Serial Line interface
! 37: *
! 38: * Rick Adams
! 39: * Center for Seismic Studies
! 40: * 1300 N 17th Street, Suite 1450
! 41: * Arlington, Virginia 22209
! 42: * (703)276-7900
! 43: * rick@seismo.ARPA
! 44: * seismo!rick
! 45: *
! 46: * Pounded on heavily by Chris Torek (chris@mimsy.umd.edu, umcp-cs!chris).
! 47: * N.B.: this belongs in netinet, not net, the way it stands now.
! 48: * Should have a link-layer type designation, but wouldn't be
! 49: * backwards-compatible.
! 50: *
! 51: * Converted to 4.3BSD Beta by Chris Torek.
! 52: * Other changes made at Berkeley, based in part on code by Kirk Smith.
! 53: * W. Jolitz added slip abort.
! 54: *
! 55: * Hacked almost beyond recognition by Van Jacobson (van@helios.ee.lbl.gov).
! 56: * Added priority queuing for "interactive" traffic; hooks for TCP
! 57: * header compression; ICMP filtering (at 2400 baud, some cretin
! 58: * pinging you can use up all your bandwidth). Made low clist behavior
! 59: * more robust and slightly less likely to hang serial line.
! 60: * Sped up a bunch of things.
! 61: */
! 62:
! 63: #include "bpfilter.h"
! 64:
! 65: #include <sys/param.h>
! 66: #include <sys/proc.h>
! 67: #include <sys/mbuf.h>
! 68: #include <sys/dkstat.h>
! 69: #include <sys/socket.h>
! 70: #include <sys/ioctl.h>
! 71: #include <sys/file.h>
! 72: #include <sys/tty.h>
! 73: #include <sys/kernel.h>
! 74: #include <sys/conf.h>
! 75: #if defined(__NetBSD__) || defined(__OpenBSD__)
! 76: #include <sys/systm.h>
! 77: #endif
! 78:
! 79: #include <machine/cpu.h>
! 80:
! 81: #include <net/if.h>
! 82: #include <net/if_types.h>
! 83: #include <net/netisr.h>
! 84: #include <net/route.h>
! 85:
! 86: #if INET
! 87: #include <netinet/in.h>
! 88: #include <netinet/in_systm.h>
! 89: #include <netinet/in_var.h>
! 90: #include <netinet/ip.h>
! 91: #else
! 92: #error Huh? Slip without inet?
! 93: #endif
! 94:
! 95: #include <net/slcompress.h>
! 96: #include <net/if_slvar.h>
! 97: #include <net/slip.h>
! 98:
! 99: #if NBPFILTER > 0
! 100: #include <sys/time.h>
! 101: #include <net/bpf.h>
! 102: #endif
! 103:
! 104: /*
! 105: * SLMAX is a hard limit on input packet size. To simplify the code
! 106: * and improve performance, we require that packets fit in an mbuf
! 107: * cluster, and if we get a compressed packet, there's enough extra
! 108: * room to expand the header into a max length tcp/ip header (128
! 109: * bytes). So, SLMAX can be at most
! 110: * MCLBYTES - 128
! 111: *
! 112: * SLMTU is a hard limit on output packet size. To insure good
! 113: * interactive response, SLMTU wants to be the smallest size that
! 114: * amortizes the header cost. (Remember that even with
! 115: * type-of-service queuing, we have to wait for any in-progress
! 116: * packet to finish. I.e., we wait, on the average, 1/2 * mtu /
! 117: * cps, where cps is the line speed in characters per second.
! 118: * E.g., 533ms wait for a 1024 byte MTU on a 9600 baud line. The
! 119: * average compressed header size is 6-8 bytes so any MTU > 90
! 120: * bytes will give us 90% of the line bandwidth. A 100ms wait is
! 121: * tolerable (500ms is not), so want an MTU around 296. (Since TCP
! 122: * will send 256 byte segments (to allow for 40 byte headers), the
! 123: * typical packet size on the wire will be around 260 bytes). In
! 124: * 4.3tahoe+ systems, we can set an MTU in a route so we do that &
! 125: * leave the interface MTU relatively high (so we don't IP fragment
! 126: * when acting as a gateway to someone using a stupid MTU).
! 127: *
! 128: * Similar considerations apply to SLIP_HIWAT: It's the amount of
! 129: * data that will be queued 'downstream' of us (i.e., in clists
! 130: * waiting to be picked up by the tty output interrupt). If we
! 131: * queue a lot of data downstream, it's immune to our t.o.s. queuing.
! 132: * E.g., if SLIP_HIWAT is 1024, the interactive traffic in mixed
! 133: * telnet/ftp will see a 1 sec wait, independent of the mtu (the
! 134: * wait is dependent on the ftp window size but that's typically
! 135: * 1k - 4k). So, we want SLIP_HIWAT just big enough to amortize
! 136: * the cost (in idle time on the wire) of the tty driver running
! 137: * off the end of its clists & having to call back slstart for a
! 138: * new packet. For a tty interface with any buffering at all, this
! 139: * cost will be zero. Even with a totally brain dead interface (like
! 140: * the one on a typical workstation), the cost will be <= 1 character
! 141: * time. So, setting SLIP_HIWAT to ~100 guarantees that we'll lose
! 142: * at most 1% while maintaining good interactive response.
! 143: */
! 144: #if NBPFILTER > 0
! 145: #define BUFOFFSET (128+sizeof(struct ifnet **)+SLIP_HDRLEN)
! 146: #else
! 147: #define BUFOFFSET (128+sizeof(struct ifnet **))
! 148: #endif
! 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 Huh? SLMTU way too small.
! 156: #endif
! 157: #define SLIP_HIWAT roundup(50,CBSIZE)
! 158: #if !(defined(__NetBSD__) || defined(__OpenBSD__)) /* 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:
! 175: #define FRAME_END 0xc0 /* Frame End */
! 176: #define FRAME_ESCAPE 0xdb /* Frame Esc */
! 177: #define TRANS_FRAME_END 0xdc /* transposed frame end */
! 178: #define TRANS_FRAME_ESCAPE 0xdd /* transposed frame esc */
! 179:
! 180: static int slinit(struct sl_softc *);
! 181: static struct mbuf *sl_btom(struct sl_softc *, int);
! 182:
! 183: int sl_clone_create(struct if_clone *, int);
! 184: int sl_clone_destroy(struct ifnet *);
! 185:
! 186: LIST_HEAD(, sl_softc) sl_softc_list;
! 187: struct if_clone sl_cloner =
! 188: IF_CLONE_INITIALIZER("sl", sl_clone_create, sl_clone_destroy);
! 189:
! 190: /*
! 191: * Called from boot code to establish sl interfaces.
! 192: */
! 193: void
! 194: slattach(n)
! 195: int n;
! 196: {
! 197: LIST_INIT(&sl_softc_list);
! 198: if_clone_attach(&sl_cloner);
! 199: }
! 200:
! 201: int
! 202: sl_clone_create(ifc, unit)
! 203: struct if_clone *ifc;
! 204: int unit;
! 205: {
! 206: struct sl_softc *sc;
! 207: int s;
! 208:
! 209: sc = malloc(sizeof(*sc), M_DEVBUF, M_NOWAIT);
! 210: if (!sc)
! 211: return (ENOMEM);
! 212: bzero(sc, sizeof(*sc));
! 213:
! 214: sc->sc_unit = unit; /* XXX */
! 215: snprintf(sc->sc_if.if_xname, sizeof sc->sc_if.if_xname, "%s%d",
! 216: ifc->ifc_name, unit);
! 217: sc->sc_if.if_softc = sc;
! 218: sc->sc_if.if_mtu = SLMTU;
! 219: sc->sc_if.if_flags =
! 220: IFF_POINTOPOINT | SC_AUTOCOMP | IFF_MULTICAST;
! 221: sc->sc_if.if_type = IFT_SLIP;
! 222: sc->sc_if.if_ioctl = slioctl;
! 223: sc->sc_if.if_output = sloutput;
! 224: IFQ_SET_MAXLEN(&sc->sc_if.if_snd, 50);
! 225: sc->sc_fastq.ifq_maxlen = 32;
! 226: IFQ_SET_READY(&sc->sc_if.if_snd);
! 227: if_attach(&sc->sc_if);
! 228: if_alloc_sadl(&sc->sc_if);
! 229: #if NBPFILTER > 0
! 230: bpfattach(&sc->sc_bpf, &sc->sc_if, DLT_SLIP, SLIP_HDRLEN);
! 231: #endif
! 232: s = splnet();
! 233: LIST_INSERT_HEAD(&sl_softc_list, sc, sc_list);
! 234: splx(s);
! 235:
! 236: return (0);
! 237: }
! 238:
! 239: int
! 240: sl_clone_destroy(ifp)
! 241: struct ifnet *ifp;
! 242: {
! 243: struct sl_softc *sc = ifp->if_softc;
! 244: int s;
! 245:
! 246: if (sc->sc_ttyp != NULL)
! 247: return (EBUSY);
! 248:
! 249: s = splnet();
! 250: LIST_REMOVE(sc, sc_list);
! 251: splx(s);
! 252:
! 253: if_detach(ifp);
! 254:
! 255: free(sc, M_DEVBUF);
! 256: return (0);
! 257: }
! 258:
! 259: static int
! 260: slinit(sc)
! 261: struct sl_softc *sc;
! 262: {
! 263: if (sc->sc_ep == (u_char *) 0) {
! 264: MGETHDR(sc->sc_mbuf, M_WAIT, MT_DATA);
! 265: if (sc->sc_mbuf)
! 266: MCLGET(sc->sc_mbuf, M_WAIT);
! 267: if (sc->sc_mbuf == NULL || sc->sc_mbuf->m_ext.ext_buf == NULL) {
! 268: printf("sl%d: can't allocate buffer\n", sc->sc_unit);
! 269: sc->sc_if.if_flags &= ~IFF_UP;
! 270: return (0);
! 271: }
! 272: }
! 273: sc->sc_ep = (u_char *) sc->sc_mbuf->m_ext.ext_buf +
! 274: sc->sc_mbuf->m_ext.ext_size;
! 275: sc->sc_mp = sc->sc_pktstart = (u_char *) sc->sc_mbuf->m_ext.ext_buf +
! 276: BUFOFFSET;
! 277:
! 278: sl_compress_init(&sc->sc_comp);
! 279:
! 280: return (1);
! 281: }
! 282:
! 283: /*
! 284: * Line specific open routine.
! 285: * Attach the given tty to the first available sl unit.
! 286: */
! 287: /* ARGSUSED */
! 288: int
! 289: slopen(dev, tp)
! 290: dev_t dev;
! 291: struct tty *tp;
! 292: {
! 293: struct proc *p = curproc; /* XXX */
! 294: struct sl_softc *sc;
! 295: int error, s;
! 296:
! 297: if ((error = suser(p, 0)) != 0)
! 298: return (error);
! 299:
! 300: if (tp->t_line == SLIPDISC)
! 301: return (0);
! 302:
! 303: LIST_FOREACH(sc, &sl_softc_list, sc_list)
! 304: if (sc->sc_ttyp == NULL) {
! 305: if (slinit(sc) == 0)
! 306: return (ENOBUFS);
! 307: tp->t_sc = (caddr_t)sc;
! 308: sc->sc_ttyp = tp;
! 309: sc->sc_if.if_baudrate = tp->t_ospeed;
! 310: s = spltty();
! 311: tp->t_state |= TS_ISOPEN | TS_XCLUDE;
! 312: splx(s);
! 313: ttyflush(tp, FREAD | FWRITE);
! 314: #if defined(__NetBSD__) || defined(__OpenBSD__)
! 315: /*
! 316: * make sure tty output queue is large enough
! 317: * to hold a full-sized packet (including frame
! 318: * end, and a possible extra frame end). full-sized
! 319: * packet occupies a max of 2*SLMTU bytes (because
! 320: * of possible escapes), and add two on for frame
! 321: * ends.
! 322: */
! 323: s = spltty();
! 324: if (tp->t_outq.c_cn < 2*SLMTU+2) {
! 325: sc->sc_oldbufsize = tp->t_outq.c_cn;
! 326: sc->sc_oldbufquot = tp->t_outq.c_cq != 0;
! 327:
! 328: clfree(&tp->t_outq);
! 329: error = clalloc(&tp->t_outq, 3*SLMTU, 0);
! 330: if (error) {
! 331: splx(s);
! 332: return (error);
! 333: }
! 334: } else
! 335: sc->sc_oldbufsize = sc->sc_oldbufquot = 0;
! 336: splx(s);
! 337: #endif /* NetBSD */
! 338: return (0);
! 339: }
! 340: return (ENXIO);
! 341: }
! 342:
! 343: /*
! 344: * Line specific close routine.
! 345: * Detach the tty from the sl unit.
! 346: */
! 347: void
! 348: slclose(tp)
! 349: struct tty *tp;
! 350: {
! 351: struct sl_softc *sc;
! 352: int s;
! 353:
! 354: ttywflush(tp);
! 355: tp->t_line = 0;
! 356: sc = (struct sl_softc *)tp->t_sc;
! 357: if (sc != NULL) {
! 358: s = spltty();
! 359:
! 360: if_down(&sc->sc_if);
! 361: sc->sc_ttyp = NULL;
! 362: tp->t_sc = NULL;
! 363:
! 364: m_freem(sc->sc_mbuf);
! 365: sc->sc_mbuf = NULL;
! 366: sc->sc_ep = sc->sc_mp = sc->sc_pktstart = NULL;
! 367:
! 368: #if defined(__NetBSD__) || defined(__OpenBSD__)
! 369: /* if necessary, install a new outq buffer of the appropriate size */
! 370: if (sc->sc_oldbufsize != 0) {
! 371: clfree(&tp->t_outq);
! 372: clalloc(&tp->t_outq, sc->sc_oldbufsize, sc->sc_oldbufquot);
! 373: }
! 374: #endif
! 375: splx(s);
! 376: }
! 377: }
! 378:
! 379: /*
! 380: * Line specific (tty) ioctl routine.
! 381: * Provide a way to get the sl unit number.
! 382: */
! 383: /* ARGSUSED */
! 384: int
! 385: sltioctl(tp, cmd, data, flag)
! 386: struct tty *tp;
! 387: u_long cmd;
! 388: caddr_t data;
! 389: int flag;
! 390: {
! 391: struct sl_softc *sc = (struct sl_softc *)tp->t_sc;
! 392:
! 393: switch (cmd) {
! 394: case SLIOCGUNIT:
! 395: *(int *)data = sc->sc_unit; /* XXX */
! 396: break;
! 397:
! 398: default:
! 399: return (-1);
! 400: }
! 401: return (0);
! 402: }
! 403:
! 404: /*
! 405: * Queue a packet. Start transmission if not active.
! 406: * Compression happens in slstart; if we do it here, IP TOS
! 407: * will cause us to not compress "background" packets, because
! 408: * ordering gets trashed. It can be done for all packets in slstart.
! 409: */
! 410: int
! 411: sloutput(ifp, m, dst, rtp)
! 412: struct ifnet *ifp;
! 413: struct mbuf *m;
! 414: struct sockaddr *dst;
! 415: struct rtentry *rtp;
! 416: {
! 417: struct sl_softc *sc = ifp->if_softc;
! 418: struct ip *ip;
! 419: int s, error;
! 420:
! 421: /*
! 422: * `Cannot happen' (see slioctl). Someday we will extend
! 423: * the line protocol to support other address families.
! 424: */
! 425: if (dst->sa_family != AF_INET) {
! 426: printf("%s: af%d not supported\n", sc->sc_if.if_xname,
! 427: dst->sa_family);
! 428: m_freem(m);
! 429: sc->sc_if.if_noproto++;
! 430: return (EAFNOSUPPORT);
! 431: }
! 432:
! 433: if (sc->sc_ttyp == NULL) {
! 434: m_freem(m);
! 435: return (ENETDOWN); /* sort of */
! 436: }
! 437: if ((sc->sc_ttyp->t_state & TS_CARR_ON) == 0 &&
! 438: (sc->sc_ttyp->t_cflag & CLOCAL) == 0) {
! 439: m_freem(m);
! 440: return (EHOSTUNREACH);
! 441: }
! 442: ip = mtod(m, struct ip *);
! 443: if (sc->sc_if.if_flags & SC_NOICMP && ip->ip_p == IPPROTO_ICMP) {
! 444: m_freem(m);
! 445: return (ENETRESET); /* XXX ? */
! 446: }
! 447: s = spltty();
! 448: if (sc->sc_oqlen && sc->sc_ttyp->t_outq.c_cc == sc->sc_oqlen) {
! 449: struct timeval tv, tm;
! 450:
! 451: getmicrotime(&tm);
! 452: /* if output's been stalled for too long, and restart */
! 453: timersub(&tm, &sc->sc_lastpacket, &tv);
! 454: if (tv.tv_sec > 0) {
! 455: sc->sc_otimeout++;
! 456: slstart(sc->sc_ttyp);
! 457: }
! 458: }
! 459:
! 460: (void) splnet();
! 461: IFQ_ENQUEUE(&sc->sc_if.if_snd, m, NULL, error);
! 462: if (error) {
! 463: splx(s);
! 464: sc->sc_if.if_oerrors++;
! 465: return (error);
! 466: }
! 467:
! 468: (void) spltty();
! 469: getmicrotime(&sc->sc_lastpacket);
! 470: if ((sc->sc_oqlen = sc->sc_ttyp->t_outq.c_cc) == 0)
! 471: slstart(sc->sc_ttyp);
! 472: splx(s);
! 473: return (0);
! 474: }
! 475:
! 476: /*
! 477: * Start output on interface. Get another datagram
! 478: * to send from the interface queue and map it to
! 479: * the interface before starting output.
! 480: */
! 481: void
! 482: slstart(tp)
! 483: struct tty *tp;
! 484: {
! 485: struct sl_softc *sc = (struct sl_softc *)tp->t_sc;
! 486: struct mbuf *m;
! 487: u_char *cp;
! 488: struct ip *ip;
! 489: int s;
! 490: struct mbuf *m2;
! 491: #if NBPFILTER > 0
! 492: u_char bpfbuf[SLMTU + SLIP_HDRLEN];
! 493: int len = 0;
! 494: #endif
! 495: #if !(defined(__NetBSD__) || defined(__OpenBSD__)) /* XXX - cgd */
! 496: extern int cfreecount;
! 497: #endif
! 498:
! 499: for (;;) {
! 500: /*
! 501: * If there is more in the output queue, just send it now.
! 502: * We are being called in lieu of ttstart and must do what
! 503: * it would.
! 504: */
! 505: if (tp->t_outq.c_cc != 0) {
! 506: (*tp->t_oproc)(tp);
! 507: if (tp->t_outq.c_cc > SLIP_HIWAT)
! 508: return;
! 509: }
! 510: /*
! 511: * This happens briefly when the line shuts down.
! 512: */
! 513: if (sc == NULL)
! 514: return;
! 515:
! 516: #if defined(__NetBSD__) || defined(__OpenBSD__) /* XXX - cgd */
! 517: /*
! 518: * Do not remove the packet from the IP queue if it
! 519: * doesn't look like the packet will fit into the
! 520: * current serial output queue, with a packet full of
! 521: * escapes this could be as bad as SLMTU*2+2.
! 522: */
! 523: if (tp->t_outq.c_cn - tp->t_outq.c_cc < 2*SLMTU+2)
! 524: return;
! 525: #endif /* NetBSD */
! 526:
! 527: /*
! 528: * Get a packet and send it to the interface.
! 529: */
! 530: s = splnet();
! 531: IF_DEQUEUE(&sc->sc_fastq, m);
! 532: if (m)
! 533: sc->sc_if.if_omcasts++; /* XXX */
! 534: else
! 535: IFQ_DEQUEUE(&sc->sc_if.if_snd, m);
! 536: splx(s);
! 537: if (m == NULL)
! 538: return;
! 539:
! 540: /*
! 541: * We do the header compression here rather than in sloutput
! 542: * because the packets will be out of order if we are using TOS
! 543: * queueing, and the connection id compression will get
! 544: * munged when this happens.
! 545: */
! 546: #if NBPFILTER > 0
! 547: if (sc->sc_bpf) {
! 548: /*
! 549: * We need to save the TCP/IP header before it's
! 550: * compressed. To avoid complicated code, we just
! 551: * copy the entire packet into a stack buffer (since
! 552: * this is a serial line, packets should be short
! 553: * and/or the copy should be negligible cost compared
! 554: * to the packet transmission time).
! 555: */
! 556: struct mbuf *m1 = m;
! 557: u_char *cp = bpfbuf + SLIP_HDRLEN;
! 558:
! 559: len = 0;
! 560: do {
! 561: int mlen = m1->m_len;
! 562:
! 563: bcopy(mtod(m1, caddr_t), cp, mlen);
! 564: cp += mlen;
! 565: len += mlen;
! 566: } while ((m1 = m1->m_next) != NULL);
! 567: }
! 568: #endif
! 569: if ((ip = mtod(m, struct ip *))->ip_p == IPPROTO_TCP) {
! 570: if (sc->sc_if.if_flags & SC_COMPRESS)
! 571: *mtod(m, u_char *) |= sl_compress_tcp(m, ip,
! 572: &sc->sc_comp, 1);
! 573: }
! 574: #if NBPFILTER > 0
! 575: if (sc->sc_bpf) {
! 576: /*
! 577: * Put the SLIP pseudo-"link header" in place. The
! 578: * compressed header is now at the beginning of the
! 579: * mbuf.
! 580: */
! 581: bpfbuf[SLX_DIR] = SLIPDIR_OUT;
! 582: bcopy(mtod(m, caddr_t), &bpfbuf[SLX_CHDR], CHDR_LEN);
! 583: bpf_tap(sc->sc_bpf, bpfbuf, len + SLIP_HDRLEN,
! 584: BPF_DIRECTION_OUT);
! 585: }
! 586: #endif
! 587: getmicrotime(&sc->sc_lastpacket);
! 588:
! 589: #if !(defined(__NetBSD__) || defined(__OpenBSD__)) /* XXX - cgd */
! 590: /*
! 591: * If system is getting low on clists, just flush our
! 592: * output queue (if the stuff was important, it'll get
! 593: * retransmitted).
! 594: */
! 595: if (cfreecount < CLISTRESERVE + SLMTU) {
! 596: m_freem(m);
! 597: sc->sc_if.if_collisions++;
! 598: continue;
! 599: }
! 600: #endif /* !__NetBSD__ */
! 601: /*
! 602: * The extra FRAME_END will start up a new packet, and thus
! 603: * will flush any accumulated garbage. We do this whenever
! 604: * the line may have been idle for some time.
! 605: */
! 606: if (tp->t_outq.c_cc == 0) {
! 607: ++sc->sc_if.if_obytes;
! 608: (void) putc(FRAME_END, &tp->t_outq);
! 609: }
! 610:
! 611: while (m) {
! 612: u_char *ep;
! 613:
! 614: cp = mtod(m, u_char *); ep = cp + m->m_len;
! 615: while (cp < ep) {
! 616: /*
! 617: * Find out how many bytes in the string we can
! 618: * handle without doing something special.
! 619: */
! 620: u_char *bp = cp;
! 621:
! 622: while (cp < ep) {
! 623: switch (*cp++) {
! 624: case FRAME_ESCAPE:
! 625: case FRAME_END:
! 626: --cp;
! 627: goto out;
! 628: }
! 629: }
! 630: out:
! 631: if (cp > bp) {
! 632: /*
! 633: * Put n characters at once
! 634: * into the tty output queue.
! 635: */
! 636: #if defined(__NetBSD__) || defined(__OpenBSD__) /* XXX - cgd */
! 637: if (b_to_q((u_char *)bp, cp - bp,
! 638: #else
! 639: if (b_to_q((char *)bp, cp - bp,
! 640: #endif
! 641: &tp->t_outq))
! 642: break;
! 643: sc->sc_if.if_obytes += cp - bp;
! 644: }
! 645: /*
! 646: * If there are characters left in the mbuf,
! 647: * the first one must be special..
! 648: * Put it out in a different form.
! 649: */
! 650: if (cp < ep) {
! 651: if (putc(FRAME_ESCAPE, &tp->t_outq))
! 652: break;
! 653: if (putc(*cp++ == FRAME_ESCAPE ?
! 654: TRANS_FRAME_ESCAPE : TRANS_FRAME_END,
! 655: &tp->t_outq)) {
! 656: (void) unputc(&tp->t_outq);
! 657: break;
! 658: }
! 659: sc->sc_if.if_obytes += 2;
! 660: }
! 661: }
! 662: MFREE(m, m2);
! 663: m = m2;
! 664: }
! 665:
! 666: if (putc(FRAME_END, &tp->t_outq)) {
! 667: /*
! 668: * Not enough room. Remove a char to make room
! 669: * and end the packet normally.
! 670: * If you get many collisions (more than one or two
! 671: * a day) you probably do not have enough clists
! 672: * and you should increase "nclist" in param.c.
! 673: */
! 674: (void) unputc(&tp->t_outq);
! 675: (void) putc(FRAME_END, &tp->t_outq);
! 676: sc->sc_if.if_collisions++;
! 677: } else {
! 678: ++sc->sc_if.if_obytes;
! 679: sc->sc_if.if_opackets++;
! 680: }
! 681: }
! 682: }
! 683:
! 684: /*
! 685: * Copy data buffer to mbuf chain; add ifnet pointer.
! 686: */
! 687: static struct mbuf *
! 688: sl_btom(sc, len)
! 689: struct sl_softc *sc;
! 690: int len;
! 691: {
! 692: struct mbuf *m;
! 693:
! 694: /*
! 695: * Allocate a new input buffer and swap.
! 696: */
! 697: m = sc->sc_mbuf;
! 698: MGETHDR(sc->sc_mbuf, M_DONTWAIT, MT_DATA);
! 699: if (sc->sc_mbuf == NULL) {
! 700: sc->sc_mbuf = m;
! 701: return (NULL);
! 702: }
! 703: MCLGET(sc->sc_mbuf, M_DONTWAIT);
! 704: if ((sc->sc_mbuf->m_flags & M_EXT) == 0) {
! 705: /*
! 706: * we couldn't get a cluster - if memory's this
! 707: * low, it's time to start dropping packets.
! 708: */
! 709: m_freem(sc->sc_mbuf);
! 710: sc->sc_mbuf = m;
! 711: return (NULL);
! 712: }
! 713: sc->sc_ep = (u_char *) sc->sc_mbuf->m_ext.ext_buf +
! 714: sc->sc_mbuf->m_ext.ext_size;
! 715:
! 716: m->m_data = sc->sc_pktstart;
! 717:
! 718: m->m_len = len;
! 719: m->m_pkthdr.len = len;
! 720: m->m_pkthdr.rcvif = &sc->sc_if;
! 721: return (m);
! 722: }
! 723:
! 724: /*
! 725: * tty interface receiver interrupt.
! 726: */
! 727: void
! 728: slinput(c, tp)
! 729: int c;
! 730: struct tty *tp;
! 731: {
! 732: struct sl_softc *sc;
! 733: struct mbuf *m;
! 734: int len;
! 735: int s;
! 736: #if NBPFILTER > 0
! 737: u_char chdr[CHDR_LEN];
! 738: #endif
! 739:
! 740: tk_nin++;
! 741: sc = (struct sl_softc *)tp->t_sc;
! 742: if (sc == NULL)
! 743: return;
! 744: if (c & TTY_ERRORMASK || ((tp->t_state & TS_CARR_ON) == 0 &&
! 745: (tp->t_cflag & CLOCAL) == 0)) {
! 746: sc->sc_flags |= SC_ERROR;
! 747: return;
! 748: }
! 749: c &= TTY_CHARMASK;
! 750:
! 751: ++sc->sc_if.if_ibytes;
! 752:
! 753: if (sc->sc_if.if_flags & IFF_DEBUG) {
! 754: if (c == ABT_ESC) {
! 755: /*
! 756: * If we have a previous abort, see whether
! 757: * this one is within the time limit.
! 758: */
! 759: if (sc->sc_abortcount &&
! 760: time_second >= sc->sc_starttime + ABT_WINDOW)
! 761: sc->sc_abortcount = 0;
! 762: /*
! 763: * If we see an abort after "idle" time, count it;
! 764: * record when the first abort escape arrived.
! 765: */
! 766: if (time_second >= sc->sc_lasttime + ABT_IDLE) {
! 767: if (++sc->sc_abortcount == 1)
! 768: sc->sc_starttime = time_second;
! 769: if (sc->sc_abortcount >= ABT_COUNT) {
! 770: slclose(tp);
! 771: return;
! 772: }
! 773: }
! 774: } else
! 775: sc->sc_abortcount = 0;
! 776: sc->sc_lasttime = time_second;
! 777: }
! 778:
! 779: switch (c) {
! 780:
! 781: case TRANS_FRAME_ESCAPE:
! 782: if (sc->sc_escape)
! 783: c = FRAME_ESCAPE;
! 784: break;
! 785:
! 786: case TRANS_FRAME_END:
! 787: if (sc->sc_escape)
! 788: c = FRAME_END;
! 789: break;
! 790:
! 791: case FRAME_ESCAPE:
! 792: sc->sc_escape = 1;
! 793: return;
! 794:
! 795: case FRAME_END:
! 796: if(sc->sc_flags & SC_ERROR) {
! 797: sc->sc_flags &= ~SC_ERROR;
! 798: goto newpack;
! 799: }
! 800: len = sc->sc_mp - sc->sc_pktstart;
! 801: if (len < 3)
! 802: /* less than min length packet - ignore */
! 803: goto newpack;
! 804:
! 805: #if NBPFILTER > 0
! 806: if (sc->sc_bpf) {
! 807: /*
! 808: * Save the compressed header, so we
! 809: * can tack it on later. Note that we
! 810: * will end up copying garbage in some
! 811: * cases but this is okay. We remember
! 812: * where the buffer started so we can
! 813: * compute the new header length.
! 814: */
! 815: bcopy(sc->sc_pktstart, chdr, CHDR_LEN);
! 816: }
! 817: #endif
! 818:
! 819: if ((c = (*sc->sc_pktstart & 0xf0)) != (IPVERSION << 4)) {
! 820: if (c & 0x80)
! 821: c = TYPE_COMPRESSED_TCP;
! 822: else if (c == TYPE_UNCOMPRESSED_TCP)
! 823: *sc->sc_pktstart &= 0x4f; /* XXX */
! 824: /*
! 825: * We've got something that's not an IP packet.
! 826: * If compression is enabled, try to decompress it.
! 827: * Otherwise, if `auto-enable' compression is on and
! 828: * it's a reasonable packet, decompress it and then
! 829: * enable compression. Otherwise, drop it.
! 830: */
! 831: if (sc->sc_if.if_flags & SC_COMPRESS) {
! 832: len = sl_uncompress_tcp(&sc->sc_pktstart, len,
! 833: (u_int)c, &sc->sc_comp);
! 834: if (len <= 0)
! 835: goto error;
! 836: } else if ((sc->sc_if.if_flags & SC_AUTOCOMP) &&
! 837: c == TYPE_UNCOMPRESSED_TCP && len >= 40) {
! 838: len = sl_uncompress_tcp(&sc->sc_pktstart, len,
! 839: (u_int)c, &sc->sc_comp);
! 840: if (len <= 0)
! 841: goto error;
! 842: sc->sc_if.if_flags |= SC_COMPRESS;
! 843: } else
! 844: goto error;
! 845: }
! 846:
! 847: m = sl_btom(sc, len);
! 848: if (m == NULL)
! 849: goto error;
! 850:
! 851: #if NBPFILTER > 0
! 852: if (sc->sc_bpf) {
! 853: /*
! 854: * Put the SLIP pseudo-"link header" in place.
! 855: * Note this M_PREPEND() should bever fail,
! 856: * since we know we always have enough space
! 857: * in the input buffer.
! 858: */
! 859: u_char *hp;
! 860:
! 861: M_PREPEND(m, SLIP_HDRLEN, M_DONTWAIT);
! 862: if (m == NULL)
! 863: goto error;
! 864:
! 865: hp = mtod(m, u_char *);
! 866: hp[SLX_DIR] = SLIPDIR_IN;
! 867: memcpy(&hp[SLX_CHDR], chdr, CHDR_LEN);
! 868:
! 869: s = splnet();
! 870: bpf_mtap(sc->sc_bpf, m, BPF_DIRECTION_IN);
! 871: splx(s);
! 872:
! 873: m_adj(m, SLIP_HDRLEN);
! 874: }
! 875: #endif
! 876:
! 877: sc->sc_if.if_ipackets++;
! 878: getmicrotime(&sc->sc_lastpacket);
! 879: s = splnet();
! 880: if (IF_QFULL(&ipintrq)) {
! 881: IF_DROP(&ipintrq);
! 882: sc->sc_if.if_ierrors++;
! 883: sc->sc_if.if_iqdrops++;
! 884: m_freem(m);
! 885: if (!ipintrq.ifq_congestion)
! 886: if_congestion(&ipintrq);
! 887: } else {
! 888: IF_ENQUEUE(&ipintrq, m);
! 889: schednetisr(NETISR_IP);
! 890: }
! 891: splx(s);
! 892: goto newpack;
! 893: }
! 894: if (sc->sc_mp < sc->sc_ep) {
! 895: *sc->sc_mp++ = c;
! 896: sc->sc_escape = 0;
! 897: return;
! 898: }
! 899:
! 900: /* can't put lower; would miss an extra frame */
! 901: sc->sc_flags |= SC_ERROR;
! 902:
! 903: error:
! 904: sc->sc_if.if_ierrors++;
! 905: newpack:
! 906: sc->sc_mp = sc->sc_pktstart = (u_char *) sc->sc_mbuf->m_ext.ext_buf +
! 907: BUFOFFSET;
! 908: sc->sc_escape = 0;
! 909: }
! 910:
! 911: /*
! 912: * Process an ioctl request.
! 913: */
! 914: int
! 915: slioctl(ifp, cmd, data)
! 916: struct ifnet *ifp;
! 917: u_long cmd;
! 918: caddr_t data;
! 919: {
! 920: struct sl_softc *sc = ifp->if_softc;
! 921: struct ifaddr *ifa = (struct ifaddr *)data;
! 922: struct ifreq *ifr;
! 923: int s = splnet(), error = 0;
! 924: struct sl_stats *slsp;
! 925:
! 926: switch (cmd) {
! 927:
! 928: case SIOCSIFADDR:
! 929: if (ifa->ifa_addr->sa_family == AF_INET)
! 930: ifp->if_flags |= IFF_UP;
! 931: else
! 932: error = EAFNOSUPPORT;
! 933: break;
! 934:
! 935: case SIOCSIFDSTADDR:
! 936: if (ifa->ifa_addr->sa_family != AF_INET)
! 937: error = EAFNOSUPPORT;
! 938: break;
! 939:
! 940: case SIOCADDMULTI:
! 941: case SIOCDELMULTI:
! 942: ifr = (struct ifreq *)data;
! 943: if (ifr == 0) {
! 944: error = EAFNOSUPPORT; /* XXX */
! 945: break;
! 946: }
! 947: switch (ifr->ifr_addr.sa_family) {
! 948:
! 949: #ifdef INET
! 950: case AF_INET:
! 951: break;
! 952: #endif
! 953:
! 954: default:
! 955: error = EAFNOSUPPORT;
! 956: break;
! 957: }
! 958: break;
! 959:
! 960: case SIOCGSLSTATS:
! 961: slsp = &((struct ifslstatsreq *) data)->stats;
! 962: bzero(slsp, sizeof(*slsp));
! 963: /* slsp->sl = sc->sc_stats; */
! 964: slsp->sl.sl_ibytes = sc->sc_if.if_ibytes;
! 965: slsp->sl.sl_obytes = sc->sc_if.if_obytes;
! 966: slsp->sl.sl_ipackets = sc->sc_if.if_ipackets;
! 967: slsp->sl.sl_opackets = sc->sc_if.if_opackets;
! 968: #ifdef INET
! 969: slsp->vj.vjs_packets = sc->sc_comp.sls_packets;
! 970: slsp->vj.vjs_compressed = sc->sc_comp.sls_compressed;
! 971: slsp->vj.vjs_searches = sc->sc_comp.sls_searches;
! 972: slsp->vj.vjs_misses = sc->sc_comp.sls_misses;
! 973: slsp->vj.vjs_uncompressedin = sc->sc_comp.sls_uncompressedin;
! 974: slsp->vj.vjs_compressedin = sc->sc_comp.sls_compressedin;
! 975: slsp->vj.vjs_errorin = sc->sc_comp.sls_errorin;
! 976: slsp->vj.vjs_tossed = sc->sc_comp.sls_tossed;
! 977: #endif /* INET */
! 978: break;
! 979:
! 980: default:
! 981: error = EINVAL;
! 982: }
! 983: splx(s);
! 984: return (error);
! 985: }
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