/* $OpenBSD: if_strip.c,v 1.13 2000/12/30 01:02:55 angelos Exp $ */ /* $NetBSD: if_strip.c,v 1.2.4.3 1996/08/03 00:58:32 jtc Exp $ */ /* from: NetBSD: if_sl.c,v 1.38 1996/02/13 22:00:23 christos Exp $ */ /* * Copyright 1996 The Board of Trustees of The Leland Stanford * Junior University. All Rights Reserved. * * Permission to use, copy, modify, and distribute this * software and its documentation for any purpose and without * fee is hereby granted, provided that the above copyright * notice appear in all copies. Stanford University * makes no representations about the suitability of this * software for any purpose. It is provided "as is" without * express or implied warranty. * * * This driver was contributed by Jonathan Stone. * * Starmode Radio IP interface (STRIP) for Metricom wireless radio. * This STRIP driver assumes address resolution of IP addresses to * Metricom MAC addresses is done via local link-level routes. * The link-level addresses are entered as an 8-digit packed BCD number. * To add a route for a radio at IP address 10.1.2.3, with radio * address '1234-5678', reachable via interface st0, use the command * * route add -host 10.1.2.3 -link st0:12:34:56:78 */ /* * Copyright (c) 1987, 1989, 1992, 1993 * The Regents of the University of California. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)if_sl.c 8.6 (Berkeley) 2/1/94 */ /* * Derived from: Serial Line interface written by Rick Adams (rick@seismo.gov) * * Rick Adams * Center for Seismic Studies * 1300 N 17th Street, Suite 1450 * Arlington, Virginia 22209 * (703)276-7900 * rick@seismo.ARPA * seismo!rick * * Pounded on heavily by Chris Torek (chris@mimsy.umd.edu, umcp-cs!chris). * N.B.: this belongs in netinet, not net, the way it stands now. * Should have a link-layer type designation, but wouldn't be * backwards-compatible. * * Converted to 4.3BSD Beta by Chris Torek. * Other changes made at Berkeley, based in part on code by Kirk Smith. * W. Jolitz added slip abort. * * Hacked almost beyond recognition by Van Jacobson (van@helios.ee.lbl.gov). * Added priority queuing for "interactive" traffic; hooks for TCP * header compression; ICMP filtering (at 2400 baud, some cretin * pinging you can use up all your bandwidth). Made low clist behavior * more robust and slightly less likely to hang serial line. * Sped up a bunch of things. * * Note that splimp() is used throughout to block both (tty) input * interrupts and network activity; thus, splimp must be >= spltty. */ #include "strip.h" #if NSTRIP > 0 #include "bpfilter.h" #include #include #include #include #include #include #include #include #include #include #if defined(__NetBSD__) || defined(__OpenBSD__) #include #endif #include #include #include #include #include #include #include #if INET #include #include #include #include #else #error Starmode Radio IP configured without configuring inet? #endif #include #include #include #if defined(__NetBSD__) || defined(__OpenBSD__) /* XXX -- jrs */ typedef u_char ttychar_t; #else typedef char ttychar_t; #endif #if NBPFILTER > 0 #include #include #endif /* * SLMAX is a hard limit on input packet size. To simplify the code * and improve performance, we require that packets fit in an mbuf * cluster, and if we get a compressed packet, there's enough extra * room to expand the header into a max length tcp/ip header (128 * bytes). So, SLMAX can be at most * MCLBYTES - 128 * * SLMTU is a hard limit on output packet size. To insure good * interactive response, SLMTU wants to be the smallest size that * amortizes the header cost. Remember that even with * type-of-service queuing, we have to wait for any in-progress * packet to finish. I.e., we wait, on the average, 1/2 * mtu / * cps, where cps is the line speed in characters per second. * E.g., 533ms wait for a 1024 byte MTU on a 9600 baud line. The * average compressed header size is 6-8 bytes so any MTU > 90 * bytes will give us 90% of the line bandwidth. A 100ms wait is * tolerable (500ms is not), so want an MTU around 296. (Since TCP * will send 256 byte segments (to allow for 40 byte headers), the * typical packet size on the wire will be around 260 bytes). In * 4.3tahoe+ systems, we can set an MTU in a route so we do that & * leave the interface MTU relatively high (so we don't IP fragment * when acting as a gateway to someone using a stupid MTU). * * Similar considerations apply to SLIP_HIWAT: It's the amount of * data that will be queued 'downstream' of us (i.e., in clists * waiting to be picked up by the tty output interrupt). If we * queue a lot of data downstream, it's immune to our t.o.s. queuing. * E.g., if SLIP_HIWAT is 1024, the interactive traffic in mixed * telnet/ftp will see a 1 sec wait, independent of the mtu (the * wait is dependent on the ftp window size but that's typically * 1k - 4k). So, we want SLIP_HIWAT just big enough to amortize * the cost (in idle time on the wire) of the tty driver running * off the end of its clists & having to call back slstart for a * new packet. For a tty interface with any buffering at all, this * cost will be zero. Even with a totally brain dead interface (like * the one on a typical workstation), the cost will be <= 1 character * time. So, setting SLIP_HIWAT to ~100 guarantees that we'll lose * at most 1% while maintaining good interactive response. */ #if NBPFILTER > 0 #define BUFOFFSET (128+sizeof(struct ifnet **)+SLIP_HDRLEN) #else #define BUFOFFSET (128+sizeof(struct ifnet **)) #endif #define SLMAX (MCLBYTES - BUFOFFSET) #define SLBUFSIZE (SLMAX + BUFOFFSET) #ifdef SLMTU #undef SLMTU #endif #define SLMTU 1100 /* XXX -- appromaximated. 1024 may be safer. */ #define STRIP_MTU_ONWIRE (SLMTU + 20 + STRIP_HDRLEN) /* (2*SLMTU+2 in sl.c */ #define SLIP_HIWAT roundup(50,CBSIZE) /* This is a NetBSD-1.0 or later kernel. */ #define CCOUNT(q) ((q)->c_cc) #if !(defined(__NetBSD__) || defined(__OpenBSD__)) /* XXX - cgd */ #define CLISTRESERVE 1024 /* Can't let clists get too low */ #endif /* !__NetBSD__ */ /* * SLIP ABORT ESCAPE MECHANISM: * (inspired by HAYES modem escape arrangement) * 1sec escape 1sec escape 1sec escape { 1sec escape 1sec escape } * within window time signals a "soft" exit from slip mode by remote end * if the IFF_DEBUG flag is on. */ #define ABT_ESC '\033' /* can't be t_intr - distant host must know it*/ #define ABT_IDLE 1 /* in seconds - idle before an escape */ #define ABT_COUNT 3 /* count of escapes for abort */ #define ABT_WINDOW (ABT_COUNT*2+2) /* in seconds - time to count */ struct st_softc st_softc[NSTRIP]; #define STRIP_FRAME_END 0x0D /* carriage return */ static int stripinit __P((struct st_softc *)); static struct mbuf *strip_btom __P((struct st_softc *, int)); /* * STRIP header: '*' + modem address (dddd-dddd) + '*' + mactype ('SIP0') * A Metricom packet looks like this: *
* * eg. *0000-1164*SIP0 * */ #define STRIP_ENCAP_SIZE(X) ((36) + (X)*65/64 + 2) #define STRIP_HDRLEN 15 #define STRIP_MAC_ADDR_LEN 9 /* * Star mode packet header. * (may be used for encapsulations other than STRIP.) */ #define STARMODE_ADDR_LEN 11 struct st_header { u_char starmode_addr[STARMODE_ADDR_LEN]; u_char starmode_type[4]; }; /* * Forward declarations for Metricom-specific functions. * Ideally, these would be in a library and shared across * different STRIP implementations: *BSD, Linux, etc. * */ static u_char* UnStuffData __P((u_char *src, u_char *end, u_char *dest, u_long dest_length)); static u_char* StuffData __P((u_char *src, u_long length, u_char *dest, u_char **code_ptr_ptr)); static void RecvErr __P((char *msg, struct st_softc *sc)); static void RecvErr_Message __P((struct st_softc *strip_info, u_char *sendername, u_char *msg)); void strip_resetradio __P((struct st_softc *sc, struct tty *tp)); void strip_proberadio __P((struct st_softc *sc, struct tty *tp)); void strip_watchdog __P((struct ifnet *ifp)); void strip_sendbody __P((struct st_softc *sc, struct mbuf *m)); int strip_newpacket __P((struct st_softc *sc, u_char *ptr, u_char *end)); struct mbuf * strip_send __P((struct st_softc *sc, struct mbuf *m0)); void strip_timeout __P((void *x)); #ifdef DEBUG #define DPRINTF(x) printf x #else #define DPRINTF(x) #endif /* * Radio reset macros. * The Metricom radios are not particularly well-designed for * use in packet mode (starmode). There's no easy way to tell * when the radio is in starmode. Worse, when the radios are reset * or power-cycled, they come back up in Hayes AT-emulation mode, * and there's no good way for this driver to tell. * We deal with this by peridically tickling the radio * with an invalid starmode command. If the radio doesn't * respond with an error, the driver knows to reset the radio. */ /* Radio-reset finite state machine (if_watchdog) callback rate, in seconds */ #define STRIP_WATCHDOG_INTERVAL 5 /* Period between intrusive radio probes, in seconds */ #define ST_PROBE_INTERVAL 10 /* Grace period for radio to answer probe, in seconds */ #define ST_PROBERESPONSE_INTERVAL 2 /* Be less agressive about repeated resetting. */ #define STRIP_RESET_INTERVAL 5 /* * We received a response from the radio that indicates it's in * star mode. Clear any pending probe or reset timer. * Don't probe radio again for standard polling interval. */ #define CLEAR_RESET_TIMER(sc) \ do {\ (sc)->sc_state = ST_ALIVE; \ (sc)->sc_statetimo = time.tv_sec + ST_PROBE_INTERVAL; \ } while (0) /* * we received a response from the radio that indicates it's crashed * out of starmode into Hayse mode. Reset it ASAP. */ #define FORCE_RESET(sc) \ do {\ (sc)->sc_statetimo = time.tv_sec - 1; \ (sc)->sc_state = ST_DEAD; \ /*(sc)->sc_if.if_timer = 0;*/ \ } while (0) #define RADIO_PROBE_TIMEOUT(sc) \ ((sc)-> sc_statetimo > time.tv_sec) /* * Called from boot code to establish sl interfaces. */ void stripattach(n) int n; { register struct st_softc *sc; register int i = 0; for (sc = st_softc; i < NSTRIP; sc++) { timeout_set(&sc->sc_timo, strip_timeout, sc); sc->sc_unit = i; /* XXX */ sprintf(sc->sc_if.if_xname, "strip%d", i++); sc->sc_if.if_softc = sc; sc->sc_if.if_mtu = SLMTU; sc->sc_if.if_flags = 0; sc->sc_if.if_type = IFT_OTHER; #if 0 sc->sc_if.if_flags |= SC_AUTOCOMP /* | IFF_POINTOPOINT | IFF_MULTICAST*/; #endif sc->sc_if.if_type = IFT_SLIP; sc->sc_if.if_ioctl = stripioctl; sc->sc_if.if_output = stripoutput; sc->sc_if.if_snd.ifq_maxlen = 50; sc->sc_fastq.ifq_maxlen = 32; sc->sc_if.if_watchdog = strip_watchdog; sc->sc_if.if_timer = STRIP_WATCHDOG_INTERVAL; if_attach(&sc->sc_if); #if NBPFILTER > 0 bpfattach(&sc->sc_bpf, &sc->sc_if, DLT_SLIP, SLIP_HDRLEN); #endif } } static int stripinit(sc) register struct st_softc *sc; { register caddr_t p; if (sc->sc_ep == (u_char *) 0) { MCLALLOC(p, M_WAIT); if (p) sc->sc_ep = (u_char *)p + SLBUFSIZE; else { addlog("%s: can't allocate buffer\n", sc->sc_if.if_xname); sc->sc_if.if_flags &= ~IFF_UP; return (0); } } /* Get contiguous buffer in which to de-bytestuff/rll-decode input */ if (sc->sc_rxbuf == (u_char *) 0) { MCLALLOC(p, M_WAIT); if (p) sc->sc_rxbuf = (u_char *)p + SLBUFSIZE - SLMAX; else { addlog("%s: can't allocate input buffer\n", sc->sc_if.if_xname); sc->sc_if.if_flags &= ~IFF_UP; return (0); } } /* Get contiguous buffer in which to bytestuff/rll-encode output */ if (sc->sc_txbuf == (u_char *) 0) { MCLALLOC(p, M_WAIT); if (p) sc->sc_txbuf = (u_char *)p + SLBUFSIZE - SLMAX; else { addlog("%s: can't allocate buffer\n", sc->sc_if.if_xname); sc->sc_if.if_flags &= ~IFF_UP; return (0); } } sc->sc_buf = sc->sc_ep - SLMAX; sc->sc_mp = sc->sc_buf; sl_compress_init(&sc->sc_comp); /* Initialize radio probe/reset state machine */ sc->sc_state = ST_DEAD; /* assumet the worst. */ sc->sc_statetimo = time.tv_sec; /* do reset immediately */ return (1); } /* * Line specific open routine. * Attach the given tty to the first available sl unit. */ /* ARGSUSED */ int stripopen(dev, tp) dev_t dev; register struct tty *tp; { struct proc *p = curproc; /* XXX */ register struct st_softc *sc; register int nstrip; int error; #if defined(__NetBSD__) || defined(__OpenBSD__) int s; #endif if ((error = suser(p->p_ucred, &p->p_acflag)) != 0) return (error); if (tp->t_line == STRIPDISC) return (0); for (nstrip = NSTRIP, sc = st_softc; --nstrip >= 0; sc++) if (sc->sc_ttyp == NULL) { if (stripinit(sc) == 0) return (ENOBUFS); tp->t_sc = (caddr_t)sc; sc->sc_ttyp = tp; sc->sc_if.if_baudrate = tp->t_ospeed; ttyflush(tp, FREAD | FWRITE); #if defined(__NetBSD__) || defined(__OpenBSD__) /* * Make sure tty output queue is large enough * to hold a full-sized packet (including frame * end, and a possible extra frame end). * A full-sized of 65/64) *SLMTU bytes (because * of escapes and clever RLL bytestuffing), * plus frame header, and add two on for frame ends. */ s = spltty(); if (tp->t_outq.c_cn < STRIP_MTU_ONWIRE) { sc->sc_oldbufsize = tp->t_outq.c_cn; sc->sc_oldbufquot = tp->t_outq.c_cq != 0; clfree(&tp->t_outq); error = clalloc(&tp->t_outq, 3*SLMTU, 0); if (error) { splx(s); return(error); } } else sc->sc_oldbufsize = sc->sc_oldbufquot = 0; splx(s); #endif /* __NetBSD__ */ s = spltty(); strip_resetradio(sc, tp); splx(s); return (0); } return (ENXIO); } /* * Line specific close routine. * Detach the tty from the strip unit. */ void stripclose(tp) struct tty *tp; { register struct st_softc *sc; int s; ttywflush(tp); s = splimp(); /* actually, max(spltty, splsoftnet) */ tp->t_line = 0; sc = (struct st_softc *)tp->t_sc; if (sc != NULL) { if_down(&sc->sc_if); sc->sc_ttyp = NULL; tp->t_sc = NULL; MCLFREE((caddr_t)(sc->sc_ep - SLBUFSIZE)); MCLFREE((caddr_t)(sc->sc_rxbuf - SLBUFSIZE + SLMAX)); /* XXX */ MCLFREE((caddr_t)(sc->sc_txbuf - SLBUFSIZE + SLMAX)); /* XXX */ sc->sc_ep = 0; sc->sc_mp = 0; sc->sc_buf = 0; sc->sc_rxbuf = 0; sc->sc_txbuf = 0; if (sc->sc_flags & SC_TIMEOUT) { timeout_del(&sc->sc_timo); sc->sc_flags &= ~SC_TIMEOUT; } } #if defined(__NetBSD__) || defined(__OpenBSD__) /* if necessary, install a new outq buffer of the appropriate size */ if (sc->sc_oldbufsize != 0) { clfree(&tp->t_outq); clalloc(&tp->t_outq, sc->sc_oldbufsize, sc->sc_oldbufquot); } #endif splx(s); } /* * Line specific (tty) ioctl routine. * Provide a way to get the sl unit number. */ /* ARGSUSED */ int striptioctl(tp, cmd, data, flag) struct tty *tp; u_long cmd; caddr_t data; int flag; { struct st_softc *sc = (struct st_softc *)tp->t_sc; switch (cmd) { case SLIOCGUNIT: *(int *)data = sc->sc_unit; break; default: return (-1); } return (0); } /* * Take an mbuf chain containing a STRIP packet (no link-level header), * byte-stuff (escape) it, and enqueue it on the tty send queue. */ void strip_sendbody(sc, m) struct st_softc *sc; struct mbuf *m; { register struct tty *tp = sc->sc_ttyp; register u_char *dp = sc->sc_txbuf; struct mbuf *m2; register int len; u_char *rllstate_ptr = NULL; while (m) { /* * Byte-stuff/run-length encode this mbuf's data into the * output buffer. * XXX * Note that chained calls to stuffdata() * require that the stuffed data be left in the * output buffer until the entire packet is encoded. */ dp = StuffData(mtod(m, u_char *), m->m_len, dp, &rllstate_ptr); MFREE(m, m2); m = m2; } /* * Put the entire stuffed packet into the tty output queue. */ len = dp - sc->sc_txbuf; if (b_to_q((ttychar_t *)sc->sc_txbuf, len, &tp->t_outq)) { if (sc->sc_if.if_flags & IFF_DEBUG) addlog("%s: tty output overflow\n", sc->sc_if.if_xname); goto bad; } sc->sc_if.if_obytes += len; return; bad: m_freem(m); return; } /* * Prepend a STRIP header to the packet. * (based on 4.4bsd if_ppp) * * XXX manipulates tty queues with putc. * must be called at spl >= spltty. */ struct mbuf * strip_send(sc, m0) struct st_softc *sc; struct mbuf *m0; { register struct tty *tp = sc->sc_ttyp; struct st_header *hdr; /* * Send starmode header (unstuffed). */ hdr = mtod(m0, struct st_header *); if (b_to_q((ttychar_t *)hdr, STRIP_HDRLEN, &tp->t_outq)) { if (sc->sc_if.if_flags & IFF_DEBUG) addlog("%s: outq overflow writing header\n", sc->sc_if.if_xname); m_freem(m0); return 0; } /* The header has been enqueued in clear; undo the M_PREPEND() of the header. */ m0->m_data += sizeof(struct st_header); m0->m_len -= sizeof(struct st_header); if (m0 && m0->m_flags & M_PKTHDR) { m0->m_pkthdr.len -= sizeof(struct st_header); } #ifdef DIAGNOSTIC else addlog("%s: strip_send: missing pkthdr, %d remains\n", sc->sc_if.if_xname, m0->m_len); /*XXX*/ #endif /* * If M_PREPEND() had to prepend a new mbuf, it is now empty. * Discard it. */ if (m0->m_len == 0) { register struct mbuf *m; MFREE(m0, m); m0 = m; } /* Byte-stuff and run-length encode the remainder of the packet. */ strip_sendbody(sc, m0); if (putc(STRIP_FRAME_END, &tp->t_outq)) { /* * Not enough room. Remove a char to make room * and end the packet normally. * If you get many collisions (more than one or two * a day) you probably do not have enough clists * and you should increase "nclist" in param.c. */ (void) unputc(&tp->t_outq); (void) putc(STRIP_FRAME_END, &tp->t_outq); sc->sc_if.if_collisions++; } else { ++sc->sc_if.if_obytes; sc->sc_if.if_opackets++; } /* * If a radio probe is due now, append it to this packet rather * than waiting until the watchdog routine next runs. */ if (time.tv_sec >= sc->sc_statetimo && sc->sc_state == ST_ALIVE) strip_proberadio(sc, tp); return(m0); } /* * Queue a packet. Start transmission if not active. * Compression happens in slstart; if we do it here, IP TOS * will cause us to not compress "background" packets, because * ordering gets trashed. It can be done for all packets in slstart. */ int stripoutput(ifp, m, dst, rt) struct ifnet *ifp; register struct mbuf *m; struct sockaddr *dst; struct rtentry *rt; { register struct st_softc *sc = ifp->if_softc; register struct ip *ip; register struct ifqueue *ifq; register struct st_header *shp; register u_char *dldst; /* link-level next-hop */ int s; u_char dl_addrbuf[STARMODE_ADDR_LEN+1]; /* * Verify tty line is up and alive. */ if (sc->sc_ttyp == NULL) { m_freem(m); return (ENETDOWN); /* sort of */ } if ((sc->sc_ttyp->t_state & TS_CARR_ON) == 0 && (sc->sc_ttyp->t_cflag & CLOCAL) == 0) { m_freem(m); return (EHOSTUNREACH); } #define SDL(a) ((struct sockaddr_dl *) (a)) #ifdef DEBUG if (rt) { printf("stripout, rt: dst af%d gw af%d", rt_key(rt)->sa_family, rt->rt_gateway->sa_family); if (rt_key(rt)->sa_family == AF_INET) printf(" dst %x", ((struct sockaddr_in *)rt_key(rt))->sin_addr.s_addr); printf("\n"); } #endif switch (dst->sa_family) { case AF_INET: if (rt != NULL && rt->rt_gwroute != NULL) rt = rt->rt_gwroute; /* assume rt is never NULL */ if (rt == NULL || rt->rt_gateway->sa_family != AF_LINK || SDL(rt->rt_gateway)->sdl_alen != ifp->if_addrlen) { DPRINTF(("strip: could not arp starmode addr %x\n", ((struct sockaddr_in *)dst)->sin_addr.s_addr)); m_freem(m); return(EHOSTUNREACH); } /*bcopy(LLADDR(SDL(rt->rt_gateway)), dldst, ifp->if_addrlen);*/ dldst = LLADDR(SDL(rt->rt_gateway)); break; case AF_LINK: /*bcopy(LLADDR(SDL(rt->rt_gateway)), dldst, ifp->if_addrlen);*/ dldst = LLADDR(SDL(dst)); break; default: /* * `Cannot happen' (see stripioctl). Someday we will extend * the line protocol to support other address families. */ addlog("%s: af %d not supported\n", sc->sc_if.if_xname, dst->sa_family); m_freem(m); sc->sc_if.if_noproto++; return (EAFNOSUPPORT); } ifq = &sc->sc_if.if_snd; ip = mtod(m, struct ip *); if (sc->sc_if.if_flags & SC_NOICMP && ip->ip_p == IPPROTO_ICMP) { m_freem(m); return (ENETRESET); /* XXX ? */ } if (ip->ip_tos & IPTOS_LOWDELAY) ifq = &sc->sc_fastq; /* * Add local net header. If no space in first mbuf, * add another. */ M_PREPEND(m, sizeof(struct st_header), M_DONTWAIT); if (m == 0) { DPRINTF(("strip: could not prepend starmode header\n")); return(ENOBUFS); } /* * Unpack BCD route entry into an ASCII starmode address. */ dl_addrbuf[0] = '*'; dl_addrbuf[1] = ((dldst[0] >> 4) & 0x0f) + '0'; dl_addrbuf[2] = ((dldst[0] ) & 0x0f) + '0'; dl_addrbuf[3] = ((dldst[1] >> 4) & 0x0f) + '0'; dl_addrbuf[4] = ((dldst[1] ) & 0x0f) + '0'; dl_addrbuf[5] = '-'; dl_addrbuf[6] = ((dldst[2] >> 4) & 0x0f) + '0'; dl_addrbuf[7] = ((dldst[2] ) & 0x0f) + '0'; dl_addrbuf[8] = ((dldst[3] >> 4) & 0x0f) + '0'; dl_addrbuf[9] = ((dldst[3] ) & 0x0f) + '0'; dl_addrbuf[10] = '*'; dl_addrbuf[11] = 0; dldst = dl_addrbuf; shp = mtod(m, struct st_header *); bcopy((caddr_t)"SIP0", (caddr_t)shp->starmode_type, sizeof(shp->starmode_type)); bcopy((caddr_t)dldst, (caddr_t)shp->starmode_addr, sizeof (shp->starmode_addr)); s = splimp(); if (sc->sc_oqlen && sc->sc_ttyp->t_outq.c_cc == sc->sc_oqlen) { struct timeval tv; /* if output's been stalled for too long, and restart */ timersub(&time, &sc->sc_if.if_lastchange, &tv); if (tv.tv_sec > 0) { DPRINTF(("stripoutput: stalled, resetting\n")); sc->sc_otimeout++; stripstart(sc->sc_ttyp); } } if (IF_QFULL(ifq)) { IF_DROP(ifq); m_freem(m); splx(s); sc->sc_if.if_oerrors++; return (ENOBUFS); } IF_ENQUEUE(ifq, m); sc->sc_if.if_lastchange = time; if ((sc->sc_oqlen = sc->sc_ttyp->t_outq.c_cc) == 0) { stripstart(sc->sc_ttyp); } /* * slip doesn't call its start routine unconditionally (again) * here, but doing so apepars to reduce latency. */ stripstart(sc->sc_ttyp); splx(s); return (0); } /* * Start output on interface. Get another datagram * to send from the interface queue and map it to * the interface before starting output. * */ void stripstart(tp) register struct tty *tp; { register struct st_softc *sc = (struct st_softc *)tp->t_sc; register struct mbuf *m; register struct ip *ip; int s; #if NBPFILTER > 0 u_char bpfbuf[SLMTU + SLIP_HDRLEN]; register int len = 0; #endif #if !(defined(__NetBSD__) || defined(__OpenBSD__)) /* XXX - cgd */ extern int cfreecount; #endif /* * Ppp checks that strip is still the line discipline, * and if not, calls t_oproc here. sl.c does not. * PPP is newer... */ if (((tp->t_state & TS_CARR_ON) == 0 && (tp->t_cflag & CLOCAL) == 0) || sc == NULL || tp != (struct tty *) sc->sc_ttyp) { if (tp->t_oproc != NULL) (*tp->t_oproc)(tp); if (sc && (sc->sc_if.if_flags & IFF_DEBUG)) addlog("%s: late call to stripstart\n ", sc->sc_if.if_xname); } /* Start any pending output asap */ if (CCOUNT(&tp->t_outq) != 0) { (*tp->t_oproc)(tp); } while (CCOUNT(&tp->t_outq) < SLIP_HIWAT) { /* * This happens briefly when the line shuts down. */ if (sc == NULL) { return; } #if defined(__NetBSD__) || defined(__OpenBSD__) /* XXX - cgd */ /* * Do not remove the packet from the IP queue if it * doesn't look like the packet will fit into the * current serial output queue, with a packet full of * escapes this could be as bad as STRIP_MTU_ONWIRE * (for slip, SLMTU*2+2, for STRIP, header + 20 bytes). * Also allow 4 bytes in case we need to send a probe * to the radio. */ if (tp->t_outq.c_cn - tp->t_outq.c_cc < STRIP_MTU_ONWIRE + 4) return; #endif /* __NetBSD__ */ /* * Get a packet and send it to the interface. */ s = splimp(); IF_DEQUEUE(&sc->sc_fastq, m); if (m) sc->sc_if.if_omcasts++; /* XXX */ else IF_DEQUEUE(&sc->sc_if.if_snd, m); splx(s); if (m == NULL) { return; } /* * We do the header compression here rather than in stripoutput * because the packets will be out of order if we are using TOS * queueing, and the connection id compression will get * munged when this happens. */ #if NBPFILTER > 0 if (sc->sc_bpf) { /* * We need to save the TCP/IP header before it's * compressed. To avoid complicated code, we just * copy the entire packet into a stack buffer (since * this is a serial line, packets should be short * and/or the copy should be negligible cost compared * to the packet transmission time). */ register struct mbuf *m1 = m; register u_char *cp = bpfbuf + SLIP_HDRLEN; len = 0; do { register int mlen = m1->m_len; bcopy(mtod(m1, caddr_t), cp, mlen); cp += mlen; len += mlen; } while ((m1 = m1->m_next) != NULL); } #endif if ((ip = mtod(m, struct ip *))->ip_p == IPPROTO_TCP) { if (sc->sc_if.if_flags & SC_COMPRESS) *mtod(m, u_char *) |= sl_compress_tcp(m, ip, &sc->sc_comp, 1); } #if NBPFILTER > 0 if (sc->sc_bpf) { register u_char *cp = bpfbuf + STRIP_HDRLEN; /* * Put the SLIP pseudo-"link header" in place. The * compressed header is now at the beginning of the * mbuf. */ cp[SLX_DIR] = SLIPDIR_OUT; bcopy(mtod(m, caddr_t)+STRIP_HDRLEN, &cp[SLX_CHDR], CHDR_LEN); bpf_tap(sc->sc_bpf, cp, len + SLIP_HDRLEN); } #endif sc->sc_if.if_lastchange = time; #if !(defined(__NetBSD__) || defined(__OpenBSD__)) /* XXX - cgd */ /* * If system is getting low on clists, just flush our * output queue (if the stuff was important, it'll get * retransmitted). */ if (cfreecount < CLISTRESERVE + SLMTU) { m_freem(m); sc->sc_if.if_collisions++; continue; } #endif /* !__NetBSD__ */ if (strip_send(sc, m) == NULL) { DPRINTF(("stripsend: failed to send pkt\n")); /*XXX*/ } } #if 0 /* schedule timeout to start output */ if ((sc->sc_flags & SC_TIMEOUT) == 0) { timeout_add(&sc->sc_timo, hz); sc->sc_flags |= SC_TIMEOUT; } #endif #if 0 /* * This timeout is needed for operation on a pseudo-tty, * because the pty code doesn't call our start routine * after it has drained the t_outq. */ if ((sc->sc_flags & SC_TIMEOUT) == 0) { timeout_add(&sc->sc_timo, hz); sc->sc_flags |= SC_TIMEOUT; } #endif /* * XXX ppp calls oproc at the end of its loop, but slip * does it at the beginning. We do both. */ /* * If there is stuff in the output queue, send it now. * We are being called in lieu of ttstart and must do what it would. */ if (tp->t_oproc != NULL) (*tp->t_oproc)(tp); } /* * Copy data buffer to mbuf chain; add ifnet pointer. */ static struct mbuf * strip_btom(sc, len) register struct st_softc *sc; register int len; { register struct mbuf *m; MGETHDR(m, M_DONTWAIT, MT_DATA); if (m == NULL) return (NULL); /* * If we have more than MHLEN bytes, it's cheaper to * queue the cluster we just filled & allocate a new one * for the input buffer. Otherwise, fill the mbuf we * allocated above. Note that code in the input routine * guarantees that packet will fit in a cluster. */ if (len >= MHLEN) { MCLGET(m, M_DONTWAIT); if ((m->m_flags & M_EXT) == 0) { /* * we couldn't get a cluster - if memory's this * low, it's time to start dropping packets. */ (void) m_free(m); return (NULL); } sc->sc_ep = mtod(m, u_char *) + SLBUFSIZE; m->m_data = (caddr_t)sc->sc_buf; m->m_ext.ext_buf = (caddr_t)((long)sc->sc_buf &~ MCLOFSET); } else bcopy((caddr_t)sc->sc_buf, mtod(m, caddr_t), len); m->m_len = len; m->m_pkthdr.len = len; m->m_pkthdr.rcvif = &sc->sc_if; return (m); } /* * tty interface receiver interrupt. * * Called with a single char from the tty receiver interrupt; put * the char into the buffer containing a partial packet. If the * char is a packet delimiter, decapsulate the packet, wrap it in * an mbuf, and put it on the protocol input queue. */ void stripinput(c, tp) register int c; register struct tty *tp; { register struct st_softc *sc; register struct mbuf *m; register int len; int s; #if NBPFILTER > 0 u_char chdr[CHDR_LEN]; #endif tk_nin++; sc = (struct st_softc *)tp->t_sc; if (sc == NULL) return; if (c & TTY_ERRORMASK || ((tp->t_state & TS_CARR_ON) == 0 && (tp->t_cflag & CLOCAL) == 0)) { sc->sc_flags |= SC_ERROR; DPRINTF(("strip: input, error %x\n", c)); /* XXX */ return; } c &= TTY_CHARMASK; ++sc->sc_if.if_ibytes; /* * Accumulate characters until we see a frame terminator (\r). */ switch (c) { case '\n': /* * Error message strings from the modem are terminated with * \r\n. This driver interprets the \r as a packet terminator. * If the first character in a packet is a \n, drop it. * (it can never be the first char of a vaild frame). */ if (sc->sc_mp - sc->sc_buf == 0) break; /* Fall through to */ default: if (sc->sc_mp < sc->sc_ep) { *sc->sc_mp++ = c; } else { sc->sc_flags |= SC_ERROR; goto error; } return; case STRIP_FRAME_END: break; } /* * We only reach here if we see a CR delimiting a packet. */ len = sc->sc_mp - sc->sc_buf; #ifdef XDEBUG if (len < 15 || sc->sc_flags & SC_ERROR) addlog("stripinput: end of pkt, len %d, err %d\n", len, sc->sc_flags & SC_ERROR); /*XXX*/ #endif if(sc->sc_flags & SC_ERROR) { sc->sc_flags &= ~SC_ERROR; addlog("%s: sc error flag set. terminating packet\n", sc->sc_if.if_xname); goto newpack; } /* * We have a frame. * Process an IP packet, ARP packet, AppleTalk packet, * AT command resposne, or Starmode error. */ len = strip_newpacket(sc, sc->sc_buf, sc->sc_mp); if (len <= 1) /* less than min length packet - ignore */ goto newpack; #if NBPFILTER > 0 if (sc->sc_bpf) { /* * Save the compressed header, so we * can tack it on later. Note that we * will end up copying garbage in some * cases but this is okay. We remember * where the buffer started so we can * compute the new header length. */ bcopy(sc->sc_buf, chdr, CHDR_LEN); } #endif if ((c = (*sc->sc_buf & 0xf0)) != (IPVERSION << 4)) { if (c & 0x80) c = TYPE_COMPRESSED_TCP; else if (c == TYPE_UNCOMPRESSED_TCP) *sc->sc_buf &= 0x4f; /* XXX */ /* * We've got something that's not an IP packet. * If compression is enabled, try to decompress it. * Otherwise, if `auto-enable' compression is on and * it's a reasonable packet, decompress it and then * enable compression. Otherwise, drop it. */ if (sc->sc_if.if_flags & SC_COMPRESS) { len = sl_uncompress_tcp(&sc->sc_buf, len, (u_int)c, &sc->sc_comp); if (len <= 0) goto error; } else if ((sc->sc_if.if_flags & SC_AUTOCOMP) && c == TYPE_UNCOMPRESSED_TCP && len >= 40) { len = sl_uncompress_tcp(&sc->sc_buf, len, (u_int)c, &sc->sc_comp); if (len <= 0) goto error; sc->sc_if.if_flags |= SC_COMPRESS; } else goto error; } #if NBPFILTER > 0 if (sc->sc_bpf) { /* * Put the SLIP pseudo-"link header" in place. * We couldn't do this any earlier since * decompression probably moved the buffer * pointer. Then, invoke BPF. */ register u_char *hp = sc->sc_buf - SLIP_HDRLEN; hp[SLX_DIR] = SLIPDIR_IN; bcopy(chdr, &hp[SLX_CHDR], CHDR_LEN); bpf_tap(sc->sc_bpf, hp, len + SLIP_HDRLEN); } #endif m = strip_btom(sc, len); if (m == NULL) { goto error; } sc->sc_if.if_ipackets++; sc->sc_if.if_lastchange = time; s = splimp(); if (IF_QFULL(&ipintrq)) { IF_DROP(&ipintrq); sc->sc_if.if_ierrors++; sc->sc_if.if_iqdrops++; m_freem(m); } else { IF_ENQUEUE(&ipintrq, m); schednetisr(NETISR_IP); } splx(s); goto newpack; error: sc->sc_if.if_ierrors++; newpack: sc->sc_mp = sc->sc_buf = sc->sc_ep - SLMAX; } /* * Process an ioctl request. */ int stripioctl(ifp, cmd, data) register struct ifnet *ifp; u_long cmd; caddr_t data; { register struct ifaddr *ifa = (struct ifaddr *)data; register struct ifreq *ifr; register int s = splimp(), error = 0; switch (cmd) { case SIOCSIFADDR: if (ifa->ifa_addr->sa_family == AF_INET) ifp->if_flags |= IFF_UP; else error = EAFNOSUPPORT; break; case SIOCSIFDSTADDR: if (ifa->ifa_addr->sa_family != AF_INET) error = EAFNOSUPPORT; break; case SIOCADDMULTI: case SIOCDELMULTI: ifr = (struct ifreq *)data; if (ifr == 0) { error = EAFNOSUPPORT; /* XXX */ break; } switch (ifr->ifr_addr.sa_family) { #ifdef INET case AF_INET: break; #endif default: error = EAFNOSUPPORT; break; } break; default: #ifdef DEBUG addlog("stripioctl: unknown request 0x%lx\n", cmd); #endif error = EINVAL; } splx(s); return (error); } /* * Strip subroutines */ /* * Set a radio into starmode. * XXX must be called at spltty() or higher (e.g., splimp() */ void strip_resetradio(sc, tp) struct st_softc *sc; struct tty *tp; { #if 0 static ttychar_t InitString[] = "\r\n\r\n\r\nat\r\n\r\n\r\nate0dt**starmode\r\n**\r\n"; #else static ttychar_t InitString[] = "\r\rat\r\r\rate0q1dt**starmode\r**\r"; #endif register int i; /* * XXX Perhaps flush tty output queue? */ if (tp == NULL) return; if ((i = b_to_q(InitString, sizeof(InitString) - 1, &tp->t_outq))) { addlog("resetradio: %d chars didn't fit in tty queue\n", i); return; } sc->sc_if.if_obytes += sizeof(InitString) - 1; /* * Assume the radio is still dead, so we can detect repeated * resets (perhaps the radio is disconnected, powered off, or * is so badlyhung it needs powercycling. */ sc->sc_state = ST_DEAD; sc->sc_if.if_lastchange = time; sc->sc_statetimo = time.tv_sec + STRIP_RESET_INTERVAL; /* * XXX Does calling the tty output routine now help resets? */ (*sc->sc_ttyp->t_oproc)(tp); } /* * Send an invalid starmode packet to the radio, to induce an error message * indicating the radio is in starmode. * Update the state machine to indicate a response is expected. * Either the radio answers, which will be caught by the parser, * or the watchdog will start resetting. * * NOTE: drops chars directly on the tty output queue. * should be caled at spl >= spltty. */ void strip_proberadio(sc, tp) register struct st_softc *sc; register struct tty *tp; { int overflow; char *strip_probestr = "**"; if (sc->sc_if.if_flags & IFF_DEBUG) addlog("%s: attempting to probe radio\n", sc->sc_if.if_xname); if (tp == NULL) { addlog("%s: no tty attached\n", sc->sc_if.if_xname); return; } overflow = b_to_q((ttychar_t *)strip_probestr, 2, &tp->t_outq); if (overflow == 0) { if (sc->sc_if.if_flags & IFF_DEBUG) addlog("%s:: sent probe to radio\n", sc->sc_if.if_xname); /* Go to probe-sent state, set timeout accordingly. */ sc->sc_state = ST_PROBE_SENT; sc->sc_statetimo = time.tv_sec + ST_PROBERESPONSE_INTERVAL; } else { addlog("%s: incomplete probe, tty queue %d bytes overfull\n", sc->sc_if.if_xname, overflow); } } #ifdef DEBUG static char *strip_statenames[] = { "Alive", "Probe sent, awaiting answer", "Probe not answered, resetting" }; #endif /* * Timeout routine -- try to start more output. * Will be needed to make strip work on ptys. */ void strip_timeout(x) void *x; { struct st_softc *sc = (struct st_softc *) x; struct tty *tp = sc->sc_ttyp; int s; s = spltty(); sc->sc_flags &= ~SC_TIMEOUT; stripstart(tp); splx(s); } /* * Strip watchdog routine. * The radio hardware is balky. When sent long packets or bursts of small * packets, the radios crash and reboots into Hayes-emulation mode. * The transmit-side machinery, the error parser, and strip_watchdog() * implement a simple finite state machine. * * We attempt to send a probe to the radio every ST_PROBE seconds. There * is no direct way to tell if the radio is in starmode, so we send it a * malformed starmode packet -- a frame with no destination address -- * and expect to an "name missing" error response from the radio within * 1 second. If we hear such a response, we assume the radio is alive * for the next ST_PROBE seconds. * If we don't hear a starmode-error response from the radio, we reset it. * * Probes, and parsing of error responses, are normally done inside the send * and receive side respectively. This watchdog routine examines the * state-machine variables. If there are no packets to send to the radio * during an entire probe interval, strip_output will not be called, * so we send a probe on its behalf. */ void strip_watchdog(ifp) struct ifnet *ifp; { register struct st_softc *sc = ifp->if_softc; struct tty *tp = sc->sc_ttyp; #ifdef DEBUG if (ifp->if_flags & IFF_DEBUG) addlog("\n%s: in watchdog, state %s timeout %ld\n", ifp->if_xname, ((unsigned) sc->sc_state < 3) ? strip_statenames[sc->sc_state] : "<>", sc->sc_statetimo - time.tv_sec); #endif /* * If time in this state hasn't yet expired, return. */ if ((ifp->if_flags & IFF_UP) == 0 || sc->sc_statetimo > time.tv_sec) { goto done; } /* * The time in the current state has expired. * Take appropriate action and advance FSA to the next state. */ switch (sc->sc_state) { case ST_ALIVE: /* * A probe is due but we haven't piggybacked one on a packet. * Send a probe now. */ if (tp == NULL) break; strip_proberadio(sc, sc->sc_ttyp); (*tp->t_oproc)(tp); break; case ST_PROBE_SENT: /* * Probe sent but no response within timeout. Reset. */ addlog("%s: no answer to probe, resetting radio\n", ifp->if_xname); strip_resetradio(sc, sc->sc_ttyp); ifp->if_oerrors++; break; case ST_DEAD: /* * The radio has been sent a reset but didn't respond. * XXX warn user to remove AC adaptor and battery, * wait 5 secs, and replace. */ addlog("%s: radio reset but not responding, Trying again\n", ifp->if_xname); strip_resetradio(sc, sc->sc_ttyp); ifp->if_oerrors++; break; default: /* Cannot happen. To be safe, do a reset. */ addlog("%s: %s %d, resetting\n", sc->sc_if.if_xname, "radio-reset finite-state machine in invalid state", sc->sc_state); strip_resetradio(sc, sc->sc_ttyp); sc->sc_state = ST_DEAD; break; } done: ifp->if_timer = STRIP_WATCHDOG_INTERVAL; return; } /* * The following bytestuffing and run-length encoding/decoding * fucntions are taken, with permission from Stuart Cheshire, * from the MosquitonNet strip driver for Linux. * XXX Linux style left intact, to ease folding in updates from * the Mosquitonet group. */ /* * Process a received packet. */ int strip_newpacket(sc, ptr, end) struct st_softc *sc; register u_char *ptr, *end; { register int len = ptr - end; register u_char *name, *name_end; u_int packetlen; /* Ignore empty lines */ if (len == 0) return 0; /* Catch 'OK' responses which show radio has fallen out of starmode */ if (len >= 2 && ptr[0] == 'O' && ptr[1] == 'K') { addlog("%s: Radio is back in AT command mode: will reset\n", sc->sc_if.if_xname); FORCE_RESET(sc); /* Do reset ASAP */ return 0; } /* Check for start of address marker, and then skip over it */ if (*ptr != '*') { /* Catch other error messages */ if (ptr[0] == 'E' && ptr[1] == 'R' && ptr[2] == 'R' && ptr[3] == '_') RecvErr_Message(sc, NULL, ptr+4); /* XXX what should the message above be? */ else { RecvErr("No initial *", sc); addlog("(len = %d)\n", len); } return 0; } /* skip the '*' */ ptr++; /* Skip the return address */ name = ptr; while (ptr < end && *ptr != '*') ptr++; /* Check for end of address marker, and skip over it */ if (ptr == end) { RecvErr("No second *", sc); return 0; } name_end = ptr++; /* Check for SRIP key, and skip over it */ if (ptr[0] != 'S' || ptr[1] != 'I' || ptr[2] != 'P' || ptr[3] != '0') { if (ptr[0] == 'E' && ptr[1] == 'R' && ptr[2] == 'R' && ptr[3] == '_') { *name_end = 0; RecvErr_Message(sc, name, ptr+4); } else RecvErr("No SRIP key", sc); return 0; } ptr += 4; /* Decode start of the IP packet header */ ptr = UnStuffData(ptr, end, sc->sc_rxbuf, 4); if (ptr == 0) { RecvErr("Runt packet (hdr)", sc); return 0; } /* * The STRIP bytestuff/RLL encoding has no explicit length * of the decoded packet. Decode start of IP header, get the * IP header length and decode that many bytes in total. */ packetlen = ((u_short)sc->sc_rxbuf[2] << 8) | sc->sc_rxbuf[3]; #ifdef DIAGNOSTIC /* addlog("Packet %02x.%02x.%02x.%02x\n", sc->sc_rxbuf[0], sc->sc_rxbuf[1], sc->sc_rxbuf[2], sc->sc_rxbuf[3]); addlog("Got %d byte packet\n", packetlen); */ #endif /* Decode remainder of the IP packer */ ptr = UnStuffData(ptr, end, sc->sc_rxbuf+4, packetlen-4); if (ptr == 0) { RecvErr("Short packet", sc); return 0; } /* XXX redundant copy */ bcopy(sc->sc_rxbuf, sc->sc_buf, packetlen ); return(packetlen); } /* * Stuffing scheme: * 00 Unused (reserved character) * 01-3F Run of 2-64 different characters * 40-7F Run of 1-64 different characters plus a single zero at the end * 80-BF Run of 1-64 of the same character * C0-FF Run of 1-64 zeroes (ASCII 0) */ typedef enum { Stuff_Diff = 0x00, Stuff_DiffZero = 0x40, Stuff_Same = 0x80, Stuff_Zero = 0xC0, Stuff_NoCode = 0xFF, /* Special code, meaning no code selected */ Stuff_CodeMask = 0xC0, Stuff_CountMask = 0x3F, Stuff_MaxCount = 0x3F, Stuff_Magic = 0x0D /* The value we are eliminating */ } StuffingCode; /* * StuffData encodes the data starting at "src" for "length" bytes. * It writes it to the buffer pointed to by "dest" (which must be at least * as long as 1 + 65/64 of the input length). The output may be up to 1.6% * larger than the input for pathological input, but will usually be smaller. * StuffData returns the new value of the dest pointer as its result. * * "code_ptr_ptr" points to a "u_char *" which is used to hold * encoding state between calls, allowing an encoded packet to be * incrementally built up from small parts. * On the first call, the "u_char *" pointed to should be initialized * to NULL; between subsequent calls the calling routine should leave * the value alone and simply pass it back unchanged so that the * encoder can recover its current state. */ #define StuffData_FinishBlock(X) \ (*code_ptr = (X) ^ Stuff_Magic, code = Stuff_NoCode) static u_char* StuffData(u_char *src, u_long length, u_char *dest, u_char **code_ptr_ptr) { u_char *end = src + length; u_char *code_ptr = *code_ptr_ptr; u_char code = Stuff_NoCode, count = 0; if (!length) return(dest); if (code_ptr) { /* Recover state from last call, if applicable */ code = (*code_ptr ^ Stuff_Magic) & Stuff_CodeMask; count = (*code_ptr ^ Stuff_Magic) & Stuff_CountMask; } while (src < end) { switch (code) { /* * Stuff_NoCode: If no current code, select one */ case Stuff_NoCode: code_ptr = dest++; /* Record where we're going to put this code */ count = 0; /* Reset the count (zero means one instance) */ /* Tentatively start a new block */ if (*src == 0) { code = Stuff_Zero; src++; } else { code = Stuff_Same; *dest++ = *src++ ^ Stuff_Magic; } /* Note: We optimistically assume run of same -- which will be */ /* fixed later in Stuff_Same if it turns out not to be true. */ break; /* * Stuff_Zero: We already have at least one zero encoded */ case Stuff_Zero: /* If another zero, count it, else finish this code block */ if (*src == 0) { count++; src++; } else StuffData_FinishBlock(Stuff_Zero + count); break; /* * Stuff_Same: We already have at least one byte encoded */ case Stuff_Same: /* If another one the same, count it */ if ((*src ^ Stuff_Magic) == code_ptr[1]) { count++; src++; break; } /* else, this byte does not match this block. */ /* If we already have two or more bytes encoded, finish this code block */ if (count) { StuffData_FinishBlock(Stuff_Same + count); break; } /* else, we only have one so far, so switch to Stuff_Diff code */ code = Stuff_Diff; /* and fall through to Stuff_Diff case below */ case Stuff_Diff: /* Stuff_Diff: We have at least two *different* bytes encoded */ /* If this is a zero, must encode a Stuff_DiffZero, and begin a new block */ if (*src == 0) StuffData_FinishBlock(Stuff_DiffZero + count); /* else, if we have three in a row, it is worth starting a Stuff_Same block */ else if ((*src ^ Stuff_Magic) == dest[-1] && dest[-1] == dest[-2]) { code += count-2; if (code == Stuff_Diff) code = Stuff_Same; StuffData_FinishBlock(code); code_ptr = dest-2; /* dest[-1] already holds the correct value */ count = 2; /* 2 means three bytes encoded */ code = Stuff_Same; } /* else, another different byte, so add it to the block */ else { *dest++ = *src ^ Stuff_Magic; count++; } src++; /* Consume the byte */ break; } if (count == Stuff_MaxCount) StuffData_FinishBlock(code + count); } if (code == Stuff_NoCode) *code_ptr_ptr = NULL; else { *code_ptr_ptr = code_ptr; StuffData_FinishBlock(code + count); } return(dest); } /* * UnStuffData decodes the data at "src", up to (but not including) * "end". It writes the decoded data into the buffer pointed to by * "dst", up to a maximum of "dst_length", and returns the new * value of "src" so that a follow-on call can read more data, * continuing from where the first left off. * * There are three types of results: * 1. The source data runs out before extracting "dst_length" bytes: * UnStuffData returns NULL to indicate failure. * 2. The source data produces exactly "dst_length" bytes: * UnStuffData returns new_src = end to indicate that all bytes * were consumed. * 3. "dst_length" bytes are extracted, with more * remaining. UnStuffData returns new_src < end to indicate that * there are more bytes to be read. * * Note: The decoding may be dstructive, in that it may alter the * source data in the process of decoding it (this is necessary to * allow a follow-on call to resume correctly). */ static u_char* UnStuffData(u_char *src, u_char *end, u_char *dst, u_long dst_length) { u_char *dst_end = dst + dst_length; /* Sanity check */ if (!src || !end || !dst || !dst_length) return(NULL); while (src < end && dst < dst_end) { int count = (*src ^ Stuff_Magic) & Stuff_CountMask; switch ((*src ^ Stuff_Magic) & Stuff_CodeMask) { case Stuff_Diff: if (src+1+count >= end) return(NULL); do { *dst++ = *++src ^ Stuff_Magic; } while(--count >= 0 && dst < dst_end); if (count < 0) src += 1; else if (count == 0) *src = Stuff_Same ^ Stuff_Magic; else *src = (Stuff_Diff + count) ^ Stuff_Magic; break; case Stuff_DiffZero: if (src+1+count >= end) return(NULL); do { *dst++ = *++src ^ Stuff_Magic; } while(--count >= 0 && dst < dst_end); if (count < 0) *src = Stuff_Zero ^ Stuff_Magic; else *src = (Stuff_DiffZero + count) ^ Stuff_Magic; break; case Stuff_Same: if (src+1 >= end) return(NULL); do { *dst++ = src[1] ^ Stuff_Magic; } while(--count >= 0 && dst < dst_end); if (count < 0) src += 2; else *src = (Stuff_Same + count) ^ Stuff_Magic; break; case Stuff_Zero: do { *dst++ = 0; } while(--count >= 0 && dst < dst_end); if (count < 0) src += 1; else *src = (Stuff_Zero + count) ^ Stuff_Magic; break; } } if (dst < dst_end) return(NULL); else return(src); } /* * Log an error mesesage (for a packet received with errors?) * from the STRIP driver. */ static void RecvErr(msg, sc) char *msg; struct st_softc *sc; { static const int MAX_RecErr = 80; u_char *ptr = sc->sc_buf; u_char *end = sc->sc_mp; u_char pkt_text[MAX_RecErr], *p = pkt_text; *p++ = '\"'; while (ptr < end && p < &pkt_text[MAX_RecErr-4]) { if (*ptr == '\\') { *p++ = '\\'; *p++ = '\\'; } else if (*ptr >= 32 && *ptr <= 126) *p++ = *ptr; else { sprintf(p, "\\%02x", *ptr); p+= 3; } ptr++; } if (ptr == end) *p++ = '\"'; *p++ = 0; addlog("%s: %13s : %s\n", sc->sc_if.if_xname, msg, pkt_text); sc->sc_if.if_ierrors++; } /* * Parse an error message from the radio. */ static void RecvErr_Message(strip_info, sendername, msg) struct st_softc *strip_info; u_char *sendername; /*const*/ u_char *msg; { static const char ERR_001[] = "001"; /* Not in StarMode! */ static const char ERR_002[] = "002"; /* Remap handle */ static const char ERR_003[] = "003"; /* Can't resolve name */ static const char ERR_004[] = "004"; /* Name too small or missing */ static const char ERR_005[] = "005"; /* Bad count specification */ static const char ERR_006[] = "006"; /* Header too big */ static const char ERR_007[] = "007"; /* Body too big */ static const char ERR_008[] = "008"; /* Bad character in name */ static const char ERR_009[] = "009"; /* No count or line terminator */ char * if_name; if_name = strip_info->sc_if.if_xname; if (!strncmp(msg, ERR_001, sizeof(ERR_001)-1)) { RecvErr("radio error message:", strip_info); addlog("%s: Radio %s is not in StarMode\n", if_name, sendername); } else if (!strncmp(msg, ERR_002, sizeof(ERR_002)-1)) { RecvErr("radio error message:", strip_info); #ifdef notyet /*Kernel doesn't have scanf!*/ int handle; u_char newname[64]; sscanf(msg, "ERR_002 Remap handle &%d to name %s", &handle, newname); addlog("%s: Radio name %s is handle %d\n", if_name, newname, handle); #endif } else if (!strncmp(msg, ERR_003, sizeof(ERR_003)-1)) { RecvErr("radio error message:", strip_info); addlog("%s: Destination radio name is unknown\n", if_name); } else if (!strncmp(msg, ERR_004, sizeof(ERR_004)-1)) { /* * The radio reports it got a badly-framed starmode packet * from us; so it must me in starmode. */ if (strip_info->sc_if.if_flags & IFF_DEBUG) addlog("%s: radio responded to probe\n", if_name); if (strip_info->sc_state == ST_DEAD) { /* A successful reset... */ addlog("%s: Radio back in starmode\n", if_name); } CLEAR_RESET_TIMER(strip_info); } else if (!strncmp(msg, ERR_005, sizeof(ERR_005)-1)) RecvErr("radio error message:", strip_info); else if (!strncmp(msg, ERR_006, sizeof(ERR_006)-1)) RecvErr("radio error message:", strip_info); else if (!strncmp(msg, ERR_007, sizeof(ERR_007)-1)) { /* * Note: This error knocks the radio back into * command mode. */ RecvErr("radio error message:", strip_info); addlog("%s: Error! Packet size too big for radio.", if_name); FORCE_RESET(strip_info); } else if (!strncmp(msg, ERR_008, sizeof(ERR_008)-1)) { RecvErr("radio error message:", strip_info); addlog("%s: Radio name contains illegal character\n", if_name); } else if (!strncmp(msg, ERR_009, sizeof(ERR_009)-1)) RecvErr("radio error message:", strip_info); else { addlog("failed to parse ]%3s[\n", msg); RecvErr("unparsed radio error message:", strip_info); } } #endif /* NSTRIP > 0 */