/* $NetBSD: if_sl.c,v 1.39 1996/05/07 02:40:43 thorpej Exp $ */ /* * 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 */ /* * Serial Line interface * * 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 "sl.h" #if NSL > 0 #include "bpfilter.h" #include #include #include #include #include #include #include #include #include #include #include #if __NetBSD__ #include #endif #include #include #include #include #include #if INET #include #include #include #include #else Huh? Slip without inet? #endif #include #include #include #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) #ifndef SLMTU #define SLMTU 296 #endif #if (SLMTU < 3) Huh? SLMTU way too small. #endif #define SLIP_HIWAT roundup(50,CBSIZE) #ifndef NetBSD /* 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 sl_softc sl_softc[NSL]; #define FRAME_END 0xc0 /* Frame End */ #define FRAME_ESCAPE 0xdb /* Frame Esc */ #define TRANS_FRAME_END 0xdc /* transposed frame end */ #define TRANS_FRAME_ESCAPE 0xdd /* transposed frame esc */ static int slinit __P((struct sl_softc *)); static struct mbuf *sl_btom __P((struct sl_softc *, int)); /* * Called from boot code to establish sl interfaces. */ void slattach() { register struct sl_softc *sc; register int i = 0; for (sc = sl_softc; i < NSL; sc++) { sprintf(sc->sc_if.if_xname, "sl%d", i++); sc->sc_if.if_softc = sc; sc->sc_unit = i; /* XXX */ sc->sc_if.if_mtu = SLMTU; sc->sc_if.if_flags = IFF_POINTOPOINT | SC_AUTOCOMP | IFF_MULTICAST; sc->sc_if.if_type = IFT_SLIP; sc->sc_if.if_ioctl = slioctl; sc->sc_if.if_output = sloutput; sc->sc_if.if_snd.ifq_maxlen = 50; sc->sc_fastq.ifq_maxlen = 32; if_attach(&sc->sc_if); #if NBPFILTER > 0 bpfattach(&sc->sc_bpf, &sc->sc_if, DLT_SLIP, SLIP_HDRLEN); #endif } } static int slinit(sc) register struct sl_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 { printf("sl%d: can't allocate buffer\n", sc - sl_softc); 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, -1); return (1); } /* * Line specific open routine. * Attach the given tty to the first available sl unit. */ /* ARGSUSED */ int slopen(dev, tp) dev_t dev; register struct tty *tp; { struct proc *p = curproc; /* XXX */ register struct sl_softc *sc; register int nsl; int error; #ifdef NetBSD int s; #endif if ((error = suser(p->p_ucred, &p->p_acflag)) != 0) return (error); if (tp->t_line == SLIPDISC) return (0); for (nsl = NSL, sc = sl_softc; --nsl >= 0; sc++) if (sc->sc_ttyp == NULL) { if (slinit(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); #ifdef NetBSD /* * make sure tty output queue is large enough * to hold a full-sized packet (including frame * end, and a possible extra frame end). full-sized * packet occupies a max of 2*SLMTU bytes (because * of possible escapes), and add two on for frame * ends. */ s = spltty(); if (tp->t_outq.c_cn < 2*SLMTU+2) { 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 */ return (0); } return (ENXIO); } /* * Line specific close routine. * Detach the tty from the sl unit. */ void slclose(tp) struct tty *tp; { register struct sl_softc *sc; int s; ttywflush(tp); s = splimp(); /* actually, max(spltty, splsoftnet) */ tp->t_line = 0; sc = (struct sl_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)); sc->sc_ep = 0; sc->sc_mp = 0; sc->sc_buf = 0; } #ifdef NetBSD /* 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 sltioctl(tp, cmd, data, flag) struct tty *tp; u_long cmd; caddr_t data; int flag; { struct sl_softc *sc = (struct sl_softc *)tp->t_sc; switch (cmd) { case SLIOCGUNIT: *(int *)data = sc->sc_unit; /* XXX */ break; default: return (-1); } return (0); } /* * 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 sloutput(ifp, m, dst, rtp) struct ifnet *ifp; register struct mbuf *m; struct sockaddr *dst; struct rtentry *rtp; { register struct sl_softc *sc = ifp->if_softc; register struct ip *ip; register struct ifqueue *ifq; int s; /* * `Cannot happen' (see slioctl). Someday we will extend * the line protocol to support other address families. */ if (dst->sa_family != AF_INET) { printf("%s: af%d not supported\n", sc->sc_if.if_xname, dst->sa_family); m_freem(m); sc->sc_if.if_noproto++; return (EAFNOSUPPORT); } 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); } 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; 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) { sc->sc_otimeout++; slstart(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) slstart(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 slstart(tp) register struct tty *tp; { register struct sl_softc *sc = (struct sl_softc *)tp->t_sc; register struct mbuf *m; register u_char *cp; register struct ip *ip; int s; struct mbuf *m2; #if NBPFILTER > 0 u_char bpfbuf[SLMTU + SLIP_HDRLEN]; register int len = 0; #endif #ifndef NetBSD /* XXX - cgd */ extern int cfreecount; #endif for (;;) { /* * If there is more in the output queue, just send it now. * We are being called in lieu of ttstart and must do what * it would. */ if (tp->t_outq.c_cc != 0) { (*tp->t_oproc)(tp); if (tp->t_outq.c_cc > SLIP_HIWAT) return; } /* * This happens briefly when the line shuts down. */ if (sc == NULL) return; #ifdef NetBSD /* 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 SLMTU*2+2. */ if (tp->t_outq.c_cn - tp->t_outq.c_cc < 2*SLMTU+2) 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 sloutput * 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) { /* * Put the SLIP pseudo-"link header" in place. The * compressed header is now at the beginning of the * mbuf. */ bpfbuf[SLX_DIR] = SLIPDIR_OUT; bcopy(mtod(m, caddr_t), &bpfbuf[SLX_CHDR], CHDR_LEN); bpf_tap(sc->sc_bpf, bpfbuf, len + SLIP_HDRLEN); } #endif sc->sc_if.if_lastchange = time; #ifndef __NetBSD__ /* 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__ */ /* * The extra FRAME_END will start up a new packet, and thus * will flush any accumulated garbage. We do this whenever * the line may have been idle for some time. */ if (tp->t_outq.c_cc == 0) { ++sc->sc_if.if_obytes; (void) putc(FRAME_END, &tp->t_outq); } while (m) { register u_char *ep; cp = mtod(m, u_char *); ep = cp + m->m_len; while (cp < ep) { /* * Find out how many bytes in the string we can * handle without doing something special. */ register u_char *bp = cp; while (cp < ep) { switch (*cp++) { case FRAME_ESCAPE: case FRAME_END: --cp; goto out; } } out: if (cp > bp) { /* * Put n characters at once * into the tty output queue. */ #ifdef __NetBSD__ /* XXX - cgd */ if (b_to_q((u_char *)bp, cp - bp, #else if (b_to_q((char *)bp, cp - bp, #endif &tp->t_outq)) break; sc->sc_if.if_obytes += cp - bp; } /* * If there are characters left in the mbuf, * the first one must be special.. * Put it out in a different form. */ if (cp < ep) { if (putc(FRAME_ESCAPE, &tp->t_outq)) break; if (putc(*cp++ == FRAME_ESCAPE ? TRANS_FRAME_ESCAPE : TRANS_FRAME_END, &tp->t_outq)) { (void) unputc(&tp->t_outq); break; } sc->sc_if.if_obytes += 2; } } MFREE(m, m2); m = m2; } if (putc(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(FRAME_END, &tp->t_outq); sc->sc_if.if_collisions++; } else { ++sc->sc_if.if_obytes; sc->sc_if.if_opackets++; } } } /* * Copy data buffer to mbuf chain; add ifnet pointer. */ static struct mbuf * sl_btom(sc, len) register struct sl_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. */ void slinput(c, tp) register int c; register struct tty *tp; { register struct sl_softc *sc; register struct mbuf *m; register int len; int s; #if NBPFILTER > 0 u_char chdr[CHDR_LEN]; #endif tk_nin++; sc = (struct sl_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; return; } c &= TTY_CHARMASK; ++sc->sc_if.if_ibytes; if (sc->sc_if.if_flags & IFF_DEBUG) { if (c == ABT_ESC) { /* * If we have a previous abort, see whether * this one is within the time limit. */ if (sc->sc_abortcount && time.tv_sec >= sc->sc_starttime + ABT_WINDOW) sc->sc_abortcount = 0; /* * If we see an abort after "idle" time, count it; * record when the first abort escape arrived. */ if (time.tv_sec >= sc->sc_lasttime + ABT_IDLE) { if (++sc->sc_abortcount == 1) sc->sc_starttime = time.tv_sec; if (sc->sc_abortcount >= ABT_COUNT) { slclose(tp); return; } } } else sc->sc_abortcount = 0; sc->sc_lasttime = time.tv_sec; } switch (c) { case TRANS_FRAME_ESCAPE: if (sc->sc_escape) c = FRAME_ESCAPE; break; case TRANS_FRAME_END: if (sc->sc_escape) c = FRAME_END; break; case FRAME_ESCAPE: sc->sc_escape = 1; return; case FRAME_END: if(sc->sc_flags & SC_ERROR) { sc->sc_flags &= ~SC_ERROR; goto newpack; } len = sc->sc_mp - sc->sc_buf; if (len < 3) /* 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 = sl_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; } if (sc->sc_mp < sc->sc_ep) { *sc->sc_mp++ = c; sc->sc_escape = 0; return; } /* can't put lower; would miss an extra frame */ sc->sc_flags |= SC_ERROR; error: sc->sc_if.if_ierrors++; newpack: sc->sc_mp = sc->sc_buf = sc->sc_ep - SLMAX; sc->sc_escape = 0; } /* * Process an ioctl request. */ int slioctl(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: error = EINVAL; } splx(s); return (error); } #endif