File: [local] / sys / net / if_sl.c (download)
Revision 1.1, Tue Mar 4 16:16:24 2008 UTC (16 years, 6 months ago) by nbrk
Branch point for: MAIN
Initial revision
|
/* $OpenBSD: if_sl.c,v 1.32 2006/03/25 22:41:47 djm Exp $ */
/* $NetBSD: if_sl.c,v 1.39.4.1 1996/06/02 16:26:31 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. 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.
*/
#include "bpfilter.h"
#include <sys/param.h>
#include <sys/proc.h>
#include <sys/mbuf.h>
#include <sys/dkstat.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <sys/file.h>
#include <sys/tty.h>
#include <sys/kernel.h>
#include <sys/conf.h>
#if defined(__NetBSD__) || defined(__OpenBSD__)
#include <sys/systm.h>
#endif
#include <machine/cpu.h>
#include <net/if.h>
#include <net/if_types.h>
#include <net/netisr.h>
#include <net/route.h>
#if INET
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/in_var.h>
#include <netinet/ip.h>
#else
#error Huh? Slip without inet?
#endif
#include <net/slcompress.h>
#include <net/if_slvar.h>
#include <net/slip.h>
#if NBPFILTER > 0
#include <sys/time.h>
#include <net/bpf.h>
#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)
#error Huh? SLMTU way too small.
#endif
#define SLIP_HIWAT roundup(50,CBSIZE)
#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 */
#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(struct sl_softc *);
static struct mbuf *sl_btom(struct sl_softc *, int);
int sl_clone_create(struct if_clone *, int);
int sl_clone_destroy(struct ifnet *);
LIST_HEAD(, sl_softc) sl_softc_list;
struct if_clone sl_cloner =
IF_CLONE_INITIALIZER("sl", sl_clone_create, sl_clone_destroy);
/*
* Called from boot code to establish sl interfaces.
*/
void
slattach(n)
int n;
{
LIST_INIT(&sl_softc_list);
if_clone_attach(&sl_cloner);
}
int
sl_clone_create(ifc, unit)
struct if_clone *ifc;
int unit;
{
struct sl_softc *sc;
int s;
sc = malloc(sizeof(*sc), M_DEVBUF, M_NOWAIT);
if (!sc)
return (ENOMEM);
bzero(sc, sizeof(*sc));
sc->sc_unit = unit; /* XXX */
snprintf(sc->sc_if.if_xname, sizeof sc->sc_if.if_xname, "%s%d",
ifc->ifc_name, unit);
sc->sc_if.if_softc = sc;
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;
IFQ_SET_MAXLEN(&sc->sc_if.if_snd, 50);
sc->sc_fastq.ifq_maxlen = 32;
IFQ_SET_READY(&sc->sc_if.if_snd);
if_attach(&sc->sc_if);
if_alloc_sadl(&sc->sc_if);
#if NBPFILTER > 0
bpfattach(&sc->sc_bpf, &sc->sc_if, DLT_SLIP, SLIP_HDRLEN);
#endif
s = splnet();
LIST_INSERT_HEAD(&sl_softc_list, sc, sc_list);
splx(s);
return (0);
}
int
sl_clone_destroy(ifp)
struct ifnet *ifp;
{
struct sl_softc *sc = ifp->if_softc;
int s;
if (sc->sc_ttyp != NULL)
return (EBUSY);
s = splnet();
LIST_REMOVE(sc, sc_list);
splx(s);
if_detach(ifp);
free(sc, M_DEVBUF);
return (0);
}
static int
slinit(sc)
struct sl_softc *sc;
{
if (sc->sc_ep == (u_char *) 0) {
MGETHDR(sc->sc_mbuf, M_WAIT, MT_DATA);
if (sc->sc_mbuf)
MCLGET(sc->sc_mbuf, M_WAIT);
if (sc->sc_mbuf == NULL || sc->sc_mbuf->m_ext.ext_buf == NULL) {
printf("sl%d: can't allocate buffer\n", sc->sc_unit);
sc->sc_if.if_flags &= ~IFF_UP;
return (0);
}
}
sc->sc_ep = (u_char *) sc->sc_mbuf->m_ext.ext_buf +
sc->sc_mbuf->m_ext.ext_size;
sc->sc_mp = sc->sc_pktstart = (u_char *) sc->sc_mbuf->m_ext.ext_buf +
BUFOFFSET;
sl_compress_init(&sc->sc_comp);
return (1);
}
/*
* Line specific open routine.
* Attach the given tty to the first available sl unit.
*/
/* ARGSUSED */
int
slopen(dev, tp)
dev_t dev;
struct tty *tp;
{
struct proc *p = curproc; /* XXX */
struct sl_softc *sc;
int error, s;
if ((error = suser(p, 0)) != 0)
return (error);
if (tp->t_line == SLIPDISC)
return (0);
LIST_FOREACH(sc, &sl_softc_list, sc_list)
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;
s = spltty();
tp->t_state |= TS_ISOPEN | TS_XCLUDE;
splx(s);
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). 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;
{
struct sl_softc *sc;
int s;
ttywflush(tp);
tp->t_line = 0;
sc = (struct sl_softc *)tp->t_sc;
if (sc != NULL) {
s = spltty();
if_down(&sc->sc_if);
sc->sc_ttyp = NULL;
tp->t_sc = NULL;
m_freem(sc->sc_mbuf);
sc->sc_mbuf = NULL;
sc->sc_ep = sc->sc_mp = sc->sc_pktstart = NULL;
#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
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;
struct mbuf *m;
struct sockaddr *dst;
struct rtentry *rtp;
{
struct sl_softc *sc = ifp->if_softc;
struct ip *ip;
int s, error;
/*
* `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);
}
ip = mtod(m, struct ip *);
if (sc->sc_if.if_flags & SC_NOICMP && ip->ip_p == IPPROTO_ICMP) {
m_freem(m);
return (ENETRESET); /* XXX ? */
}
s = spltty();
if (sc->sc_oqlen && sc->sc_ttyp->t_outq.c_cc == sc->sc_oqlen) {
struct timeval tv, tm;
getmicrotime(&tm);
/* if output's been stalled for too long, and restart */
timersub(&tm, &sc->sc_lastpacket, &tv);
if (tv.tv_sec > 0) {
sc->sc_otimeout++;
slstart(sc->sc_ttyp);
}
}
(void) splnet();
IFQ_ENQUEUE(&sc->sc_if.if_snd, m, NULL, error);
if (error) {
splx(s);
sc->sc_if.if_oerrors++;
return (error);
}
(void) spltty();
getmicrotime(&sc->sc_lastpacket);
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)
struct tty *tp;
{
struct sl_softc *sc = (struct sl_softc *)tp->t_sc;
struct mbuf *m;
u_char *cp;
struct ip *ip;
int s;
struct mbuf *m2;
#if NBPFILTER > 0
u_char bpfbuf[SLMTU + SLIP_HDRLEN];
int len = 0;
#endif
#if !(defined(__NetBSD__) || defined(__OpenBSD__)) /* 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;
#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 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 = splnet();
IF_DEQUEUE(&sc->sc_fastq, m);
if (m)
sc->sc_if.if_omcasts++; /* XXX */
else
IFQ_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).
*/
struct mbuf *m1 = m;
u_char *cp = bpfbuf + SLIP_HDRLEN;
len = 0;
do {
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,
BPF_DIRECTION_OUT);
}
#endif
getmicrotime(&sc->sc_lastpacket);
#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__ */
/*
* 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) {
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.
*/
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.
*/
#if defined(__NetBSD__) || defined(__OpenBSD__) /* 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)
struct sl_softc *sc;
int len;
{
struct mbuf *m;
/*
* Allocate a new input buffer and swap.
*/
m = sc->sc_mbuf;
MGETHDR(sc->sc_mbuf, M_DONTWAIT, MT_DATA);
if (sc->sc_mbuf == NULL) {
sc->sc_mbuf = m;
return (NULL);
}
MCLGET(sc->sc_mbuf, M_DONTWAIT);
if ((sc->sc_mbuf->m_flags & M_EXT) == 0) {
/*
* we couldn't get a cluster - if memory's this
* low, it's time to start dropping packets.
*/
m_freem(sc->sc_mbuf);
sc->sc_mbuf = m;
return (NULL);
}
sc->sc_ep = (u_char *) sc->sc_mbuf->m_ext.ext_buf +
sc->sc_mbuf->m_ext.ext_size;
m->m_data = sc->sc_pktstart;
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)
int c;
struct tty *tp;
{
struct sl_softc *sc;
struct mbuf *m;
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_second >= 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_second >= sc->sc_lasttime + ABT_IDLE) {
if (++sc->sc_abortcount == 1)
sc->sc_starttime = time_second;
if (sc->sc_abortcount >= ABT_COUNT) {
slclose(tp);
return;
}
}
} else
sc->sc_abortcount = 0;
sc->sc_lasttime = time_second;
}
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_pktstart;
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_pktstart, chdr, CHDR_LEN);
}
#endif
if ((c = (*sc->sc_pktstart & 0xf0)) != (IPVERSION << 4)) {
if (c & 0x80)
c = TYPE_COMPRESSED_TCP;
else if (c == TYPE_UNCOMPRESSED_TCP)
*sc->sc_pktstart &= 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_pktstart, 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_pktstart, len,
(u_int)c, &sc->sc_comp);
if (len <= 0)
goto error;
sc->sc_if.if_flags |= SC_COMPRESS;
} else
goto error;
}
m = sl_btom(sc, len);
if (m == NULL)
goto error;
#if NBPFILTER > 0
if (sc->sc_bpf) {
/*
* Put the SLIP pseudo-"link header" in place.
* Note this M_PREPEND() should bever fail,
* since we know we always have enough space
* in the input buffer.
*/
u_char *hp;
M_PREPEND(m, SLIP_HDRLEN, M_DONTWAIT);
if (m == NULL)
goto error;
hp = mtod(m, u_char *);
hp[SLX_DIR] = SLIPDIR_IN;
memcpy(&hp[SLX_CHDR], chdr, CHDR_LEN);
s = splnet();
bpf_mtap(sc->sc_bpf, m, BPF_DIRECTION_IN);
splx(s);
m_adj(m, SLIP_HDRLEN);
}
#endif
sc->sc_if.if_ipackets++;
getmicrotime(&sc->sc_lastpacket);
s = splnet();
if (IF_QFULL(&ipintrq)) {
IF_DROP(&ipintrq);
sc->sc_if.if_ierrors++;
sc->sc_if.if_iqdrops++;
m_freem(m);
if (!ipintrq.ifq_congestion)
if_congestion(&ipintrq);
} 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_pktstart = (u_char *) sc->sc_mbuf->m_ext.ext_buf +
BUFOFFSET;
sc->sc_escape = 0;
}
/*
* Process an ioctl request.
*/
int
slioctl(ifp, cmd, data)
struct ifnet *ifp;
u_long cmd;
caddr_t data;
{
struct sl_softc *sc = ifp->if_softc;
struct ifaddr *ifa = (struct ifaddr *)data;
struct ifreq *ifr;
int s = splnet(), error = 0;
struct sl_stats *slsp;
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;
case SIOCGSLSTATS:
slsp = &((struct ifslstatsreq *) data)->stats;
bzero(slsp, sizeof(*slsp));
/* slsp->sl = sc->sc_stats; */
slsp->sl.sl_ibytes = sc->sc_if.if_ibytes;
slsp->sl.sl_obytes = sc->sc_if.if_obytes;
slsp->sl.sl_ipackets = sc->sc_if.if_ipackets;
slsp->sl.sl_opackets = sc->sc_if.if_opackets;
#ifdef INET
slsp->vj.vjs_packets = sc->sc_comp.sls_packets;
slsp->vj.vjs_compressed = sc->sc_comp.sls_compressed;
slsp->vj.vjs_searches = sc->sc_comp.sls_searches;
slsp->vj.vjs_misses = sc->sc_comp.sls_misses;
slsp->vj.vjs_uncompressedin = sc->sc_comp.sls_uncompressedin;
slsp->vj.vjs_compressedin = sc->sc_comp.sls_compressedin;
slsp->vj.vjs_errorin = sc->sc_comp.sls_errorin;
slsp->vj.vjs_tossed = sc->sc_comp.sls_tossed;
#endif /* INET */
break;
default:
error = EINVAL;
}
splx(s);
return (error);
}