1002 lines
25 KiB
C
1002 lines
25 KiB
C
/*
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* Copyright (c) 1987, 1989, 1992, 1993
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* The Regents of the University of California. All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. All advertising materials mentioning features or use of this software
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* must display the following acknowledgement:
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* This product includes software developed by the University of
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* California, Berkeley and its contributors.
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* 4. Neither the name of the University nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*
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* @(#)if_sl.c 8.6 (Berkeley) 2/1/94
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* $Id: if_sl.c,v 1.18 1995/04/02 00:11:48 bde Exp $
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*/
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/*
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* Serial Line interface
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*
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* Rick Adams
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* Center for Seismic Studies
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* 1300 N 17th Street, Suite 1450
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* Arlington, Virginia 22209
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* (703)276-7900
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* rick@seismo.ARPA
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* seismo!rick
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*
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* Pounded on heavily by Chris Torek (chris@mimsy.umd.edu, umcp-cs!chris).
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* N.B.: this belongs in netinet, not net, the way it stands now.
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* Should have a link-layer type designation, but wouldn't be
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* backwards-compatible.
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*
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* Converted to 4.3BSD Beta by Chris Torek.
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* Other changes made at Berkeley, based in part on code by Kirk Smith.
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* W. Jolitz added slip abort.
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*
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* Hacked almost beyond recognition by Van Jacobson (van@helios.ee.lbl.gov).
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* Added priority queuing for "interactive" traffic; hooks for TCP
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* header compression; ICMP filtering (at 2400 baud, some cretin
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* pinging you can use up all your bandwidth). Made low clist behavior
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* more robust and slightly less likely to hang serial line.
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* Sped up a bunch of things.
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*
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* Note that splimp() is used throughout to block both (tty) input
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* interrupts and network activity; thus, splimp must be >= spltty.
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*/
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#include "sl.h"
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#if NSL > 0
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#include "bpfilter.h"
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#include <sys/param.h>
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#include <sys/systm.h>
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#include <sys/proc.h>
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#include <sys/mbuf.h>
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#include <sys/buf.h>
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#include <sys/dkstat.h>
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#include <sys/socket.h>
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#include <sys/ioctl.h>
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#include <sys/file.h>
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#include <sys/signalvar.h>
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#include <sys/tty.h>
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#include <sys/clist.h>
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#include <sys/kernel.h>
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#include <sys/conf.h>
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#include <machine/cpu.h>
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#include <net/if.h>
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#include <net/if_types.h>
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#include <net/netisr.h>
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#include <net/route.h>
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#if INET
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#include <netinet/in.h>
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#include <netinet/in_systm.h>
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#include <netinet/in_var.h>
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#include <netinet/ip.h>
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#else
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Huh? Slip without inet?
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#endif
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#include <net/slcompress.h>
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#include <net/if_slvar.h>
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#include <net/slip.h>
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#if NBPFILTER > 0
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#include <sys/time.h>
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#include <net/bpf.h>
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#endif
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/*
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* SLRMAX is a hard limit on input packet size. To simplify the code
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* and improve performance, we require that packets fit in an mbuf
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* cluster, and if we get a compressed packet, there's enough extra
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* room to expand the header into a max length tcp/ip header (128
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* bytes). So, SLRMAX can be at most
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* MCLBYTES - 128
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*
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* SLMTU is the default transmit MTU. The transmit MTU should be kept
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* small enough so that interactive use doesn't suffer, but large
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* enough to provide good performance. 552 is a good choice for SLMTU
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* because it is high enough to not fragment TCP packets being routed
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* through this host. Packet fragmentation is bad with SLIP because
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* fragment headers aren't compressed. The previous assumptions about
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* the best MTU value don't really hold when using modern modems with
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* BTLZ data compression because the modem buffers play a much larger
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* role in interactive performance than the MTU. The MTU can be changed
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* at any time to suit the specific environment with ifconfig(8), and
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* its maximum value is defined as SLTMAX. SLTMAX must not be so large
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* that it would overflow the stack if BPF is configured (XXX; if_ppp.c
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* handles this better).
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*
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* SLIP_HIWAT is the amount of data that will be queued 'downstream'
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* of us (i.e., in clists waiting to be picked up by the tty output
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* interrupt). If we queue a lot of data downstream, it's immune to
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* our t.o.s. queuing.
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* E.g., if SLIP_HIWAT is 1024, the interactive traffic in mixed
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* telnet/ftp will see a 1 sec wait, independent of the mtu (the
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* wait is dependent on the ftp window size but that's typically
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* 1k - 4k). So, we want SLIP_HIWAT just big enough to amortize
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* the cost (in idle time on the wire) of the tty driver running
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* off the end of its clists & having to call back slstart for a
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* new packet. For a tty interface with any buffering at all, this
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* cost will be zero. Even with a totally brain dead interface (like
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* the one on a typical workstation), the cost will be <= 1 character
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* time. So, setting SLIP_HIWAT to ~100 guarantees that we'll lose
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* at most 1% while maintaining good interactive response.
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*/
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#if NBPFILTER > 0
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#define BUFOFFSET (128+sizeof(struct ifnet **)+SLIP_HDRLEN)
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#else
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#define BUFOFFSET (128+sizeof(struct ifnet **))
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#endif
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#define SLRMAX (MCLBYTES - BUFOFFSET)
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#define SLBUFSIZE (SLRMAX + BUFOFFSET)
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#ifndef SLMTU
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#define SLMTU 552 /* default MTU */
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#endif
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#define SLTMAX 1500 /* maximum MTU */
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#define SLIP_HIWAT roundup(50,CBSIZE)
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#define CLISTRESERVE 1024 /* Can't let clists get too low */
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/*
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* SLIP ABORT ESCAPE MECHANISM:
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* (inspired by HAYES modem escape arrangement)
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* 1sec escape 1sec escape 1sec escape { 1sec escape 1sec escape }
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* within window time signals a "soft" exit from slip mode by remote end
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* if the IFF_DEBUG flag is on.
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*/
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#define ABT_ESC '\033' /* can't be t_intr - distant host must know it*/
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#define ABT_IDLE 1 /* in seconds - idle before an escape */
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#define ABT_COUNT 3 /* count of escapes for abort */
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#define ABT_WINDOW (ABT_COUNT*2+2) /* in seconds - time to count */
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struct sl_softc sl_softc[NSL];
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#define FRAME_END 0xc0 /* Frame End */
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#define FRAME_ESCAPE 0xdb /* Frame Esc */
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#define TRANS_FRAME_END 0xdc /* transposed frame end */
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#define TRANS_FRAME_ESCAPE 0xdd /* transposed frame esc */
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static int slinit __P((struct sl_softc *));
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static struct mbuf *sl_btom __P((struct sl_softc *, int));
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static timeout_t sl_keepalive;
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static timeout_t sl_outfill;
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#define ttyerrio ((int (*) __P((struct tty *, struct uio *, int)))enodev)
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static struct linesw slipdisc =
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{ slopen, slclose, ttyerrio, ttyerrio, sltioctl,
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slinput, slstart, nullmodem };
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/*
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* Called from boot code to establish sl interfaces.
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*/
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void
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slattach()
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{
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register struct sl_softc *sc;
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register int i = 0;
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linesw[SLIPDISC] = slipdisc;
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for (sc = sl_softc; i < NSL; sc++) {
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sc->sc_if.if_name = "sl";
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sc->sc_if.if_next = NULL;
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sc->sc_if.if_unit = i++;
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sc->sc_if.if_mtu = SLMTU;
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sc->sc_if.if_flags =
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IFF_POINTOPOINT | SC_AUTOCOMP | IFF_MULTICAST;
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sc->sc_if.if_type = IFT_SLIP;
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sc->sc_if.if_ioctl = slioctl;
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sc->sc_if.if_output = sloutput;
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sc->sc_if.if_snd.ifq_maxlen = 50;
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sc->sc_fastq.ifq_maxlen = 32;
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if_attach(&sc->sc_if);
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#if NBPFILTER > 0
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bpfattach(&sc->sc_bpf, &sc->sc_if, DLT_SLIP, SLIP_HDRLEN);
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#endif
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}
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}
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PSEUDO_SET(slattach, if_sl);
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static int
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slinit(sc)
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register struct sl_softc *sc;
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{
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register caddr_t p;
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if (sc->sc_ep == (u_char *) 0) {
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MCLALLOC(p, M_WAIT);
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if (p)
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sc->sc_ep = (u_char *)p + SLBUFSIZE;
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else {
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printf("sl%d: can't allocate buffer\n", sc - sl_softc);
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sc->sc_if.if_flags &= ~IFF_UP;
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return (0);
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}
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}
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sc->sc_buf = sc->sc_ep - SLRMAX;
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sc->sc_mp = sc->sc_buf;
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sl_compress_init(&sc->sc_comp);
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return (1);
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}
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/*
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* Line specific open routine.
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* Attach the given tty to the first available sl unit.
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*/
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/* ARGSUSED */
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int
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slopen(dev, tp)
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dev_t dev;
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register struct tty *tp;
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{
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struct proc *p = curproc; /* XXX */
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register struct sl_softc *sc;
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register int nsl;
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int error;
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error = suser(p->p_ucred, &p->p_acflag);
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if (error)
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return (error);
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if (tp->t_line == SLIPDISC)
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return (0);
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for (nsl = NSL, sc = sl_softc; --nsl >= 0; sc++)
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if (sc->sc_ttyp == NULL) {
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if (slinit(sc) == 0)
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return (ENOBUFS);
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tp->t_sc = (caddr_t)sc;
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sc->sc_ttyp = tp;
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sc->sc_if.if_baudrate = tp->t_ospeed;
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ttyflush(tp, FREAD | FWRITE);
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tp->t_line = SLIPDISC;
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/*
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* We don't use t_canq or t_rawq, so reduce their
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* cblock resources to 0. Reserve enough cblocks
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* for t_outq to guarantee that we can fit a full
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* packet if the SLIP_HIWAT check allows slstart()
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* to loop. Use the same value for the cblock
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* limit since the reserved blocks should always
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* be enough. Reserving cblocks probably makes
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* the CLISTRESERVE check unnecessary and wasteful.
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*/
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clist_alloc_cblocks(&tp->t_canq, 0, 0);
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clist_alloc_cblocks(&tp->t_outq,
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sc->sc_if.if_mtu + SLIP_HIWAT,
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sc->sc_if.if_mtu + SLIP_HIWAT);
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clist_alloc_cblocks(&tp->t_rawq, 0, 0);
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return (0);
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}
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return (ENXIO);
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}
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/*
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* Line specific close routine.
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* Detach the tty from the sl unit.
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*/
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int
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slclose(tp,flag)
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struct tty *tp;
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int flag;
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{
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register struct sl_softc *sc;
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int s;
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if (ttywflush(tp))
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ttyflush(tp, FREAD | FWRITE);
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/*
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* XXX the placement of the following spl is misleading. tty
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* interrupts must be blocked across line discipline switches
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* and throughout closes to avoid races.
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*/
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s = splimp(); /* actually, max(spltty, splnet) */
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clist_free_cblocks(&tp->t_outq);
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tp->t_line = 0;
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sc = (struct sl_softc *)tp->t_sc;
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if (sc != NULL) {
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if (sc->sc_outfill) {
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sc->sc_outfill = 0;
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untimeout(sl_outfill, sc);
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}
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if (sc->sc_keepalive) {
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sc->sc_keepalive = 0;
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untimeout(sl_keepalive, sc);
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}
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if_down(&sc->sc_if);
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sc->sc_flags = 0;
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sc->sc_ttyp = NULL;
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tp->t_sc = NULL;
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MCLFREE((caddr_t)(sc->sc_ep - SLBUFSIZE));
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sc->sc_ep = 0;
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sc->sc_mp = 0;
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sc->sc_buf = 0;
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}
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splx(s);
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return 0;
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}
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/*
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* Line specific (tty) ioctl routine.
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* Provide a way to get the sl unit number.
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*/
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/* ARGSUSED */
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int
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sltioctl(tp, cmd, data, flag, p)
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struct tty *tp;
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int cmd;
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caddr_t data;
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int flag;
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struct proc *p;
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{
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struct sl_softc *sc = (struct sl_softc *)tp->t_sc;
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int s;
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s = splimp();
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switch (cmd) {
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case SLIOCGUNIT:
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*(int *)data = sc->sc_if.if_unit;
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break;
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case SLIOCSUNIT:
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sc->sc_if.if_unit = *(u_int *)data;
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break;
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case SLIOCSKEEPAL:
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sc->sc_keepalive = *(u_int *)data * hz;
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if (sc->sc_keepalive) {
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sc->sc_flags |= SC_KEEPALIVE;
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timeout(sl_keepalive, sc, sc->sc_keepalive);
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} else {
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sc->sc_flags &= ~SC_KEEPALIVE;
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untimeout(sl_keepalive, sc);
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}
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break;
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case SLIOCGKEEPAL:
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*(int *)data = sc->sc_keepalive / hz;
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break;
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case SLIOCSOUTFILL:
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sc->sc_outfill = *(u_int *)data * hz;
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if (sc->sc_outfill) {
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sc->sc_flags |= SC_OUTWAIT;
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timeout(sl_outfill, sc, sc->sc_outfill);
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} else {
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sc->sc_flags &= ~SC_OUTWAIT;
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untimeout(sl_outfill, sc);
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}
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break;
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case SLIOCGOUTFILL:
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*(int *)data = sc->sc_outfill / hz;
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break;
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default:
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splx(s);
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return (-1);
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}
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splx(s);
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return (0);
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}
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/*
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* Queue a packet. Start transmission if not active.
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* Compression happens in slstart; if we do it here, IP TOS
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* will cause us to not compress "background" packets, because
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* ordering gets trashed. It can be done for all packets in slstart.
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*/
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int
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sloutput(ifp, m, dst, rtp)
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struct ifnet *ifp;
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register struct mbuf *m;
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struct sockaddr *dst;
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struct rtentry *rtp;
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{
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register struct sl_softc *sc = &sl_softc[ifp->if_unit];
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register struct ip *ip;
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register struct ifqueue *ifq;
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int s;
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/*
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* `Cannot happen' (see slioctl). Someday we will extend
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* the line protocol to support other address families.
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*/
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if (dst->sa_family != AF_INET) {
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printf("sl%d: af%d not supported\n", sc->sc_if.if_unit,
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dst->sa_family);
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m_freem(m);
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sc->sc_if.if_noproto++;
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return (EAFNOSUPPORT);
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}
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if (sc->sc_ttyp == NULL) {
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m_freem(m);
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return (ENETDOWN); /* sort of */
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}
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if ((sc->sc_ttyp->t_state & TS_CARR_ON) == 0 &&
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(sc->sc_ttyp->t_cflag & CLOCAL) == 0) {
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m_freem(m);
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return (EHOSTUNREACH);
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}
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ifq = &sc->sc_if.if_snd;
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ip = mtod(m, struct ip *);
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if (sc->sc_if.if_flags & SC_NOICMP && ip->ip_p == IPPROTO_ICMP) {
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m_freem(m);
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return (ENETRESET); /* XXX ? */
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}
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if (ip->ip_tos & IPTOS_LOWDELAY)
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ifq = &sc->sc_fastq;
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s = splimp();
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if (IF_QFULL(ifq)) {
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IF_DROP(ifq);
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m_freem(m);
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splx(s);
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sc->sc_if.if_oerrors++;
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return (ENOBUFS);
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}
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IF_ENQUEUE(ifq, m);
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sc->sc_if.if_lastchange = time;
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if (sc->sc_ttyp->t_outq.c_cc == 0)
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slstart(sc->sc_ttyp);
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splx(s);
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return (0);
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}
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/*
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* Start output on interface. Get another datagram
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* to send from the interface queue and map it to
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* the interface before starting output.
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*/
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int
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slstart(tp)
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register struct tty *tp;
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{
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register struct sl_softc *sc = (struct sl_softc *)tp->t_sc;
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register struct mbuf *m;
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register u_char *cp;
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register struct ip *ip;
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int s;
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struct mbuf *m2;
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#if NBPFILTER > 0
|
|
u_char bpfbuf[SLTMAX + SLIP_HDRLEN];
|
|
register int len = 0;
|
|
#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) {
|
|
if (sc != NULL)
|
|
sc->sc_flags &= ~SC_OUTWAIT;
|
|
(*tp->t_oproc)(tp);
|
|
if (tp->t_outq.c_cc > SLIP_HIWAT)
|
|
return 0;
|
|
}
|
|
/*
|
|
* This happens briefly when the line shuts down.
|
|
*/
|
|
if (sc == NULL)
|
|
return 0;
|
|
|
|
/*
|
|
* 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 0;
|
|
sc->sc_flags &= ~SC_OUTWAIT;
|
|
|
|
/*
|
|
* 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);
|
|
}
|
|
#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;
|
|
|
|
/*
|
|
* If system is getting low on clists, just flush our
|
|
* output queue (if the stuff was important, it'll get
|
|
* retransmitted). Note that SLTMAX is used instead of
|
|
* the current if_mtu setting because connections that
|
|
* have already been established still use the original
|
|
* (possibly larger) mss.
|
|
*/
|
|
if (cfreecount < CLISTRESERVE + SLTMAX) {
|
|
m_freem(m);
|
|
sc->sc_if.if_collisions++;
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* 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.
|
|
*/
|
|
if (b_to_q((char *)bp, cp - bp,
|
|
&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++;
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* 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)((int)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.
|
|
*/
|
|
int
|
|
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 0;
|
|
if (c & TTY_ERRORMASK || ((tp->t_state & TS_CARR_ON) == 0 &&
|
|
(tp->t_cflag & CLOCAL) == 0)) {
|
|
sc->sc_flags |= SC_ERROR;
|
|
return 0;
|
|
}
|
|
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,0);
|
|
return 0;
|
|
}
|
|
}
|
|
} 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 0;
|
|
|
|
case FRAME_END:
|
|
sc->sc_flags &= ~SC_KEEPALIVE;
|
|
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 0;
|
|
}
|
|
|
|
/* 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 - SLRMAX;
|
|
sc->sc_escape = 0;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Process an ioctl request.
|
|
*/
|
|
int
|
|
slioctl(ifp, cmd, data)
|
|
register struct ifnet *ifp;
|
|
int cmd;
|
|
caddr_t data;
|
|
{
|
|
register struct ifaddr *ifa = (struct ifaddr *)data;
|
|
register struct ifreq *ifr = (struct ifreq *)data;
|
|
register int s, error = 0;
|
|
|
|
s = splimp();
|
|
|
|
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:
|
|
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 SIOCSIFMTU:
|
|
/*
|
|
* Set the interface MTU.
|
|
*/
|
|
if (ifr->ifr_mtu > SLTMAX)
|
|
error = EINVAL;
|
|
else {
|
|
struct tty *tp;
|
|
|
|
ifp->if_mtu = ifr->ifr_mtu;
|
|
tp = sl_softc[ifp->if_unit].sc_ttyp;
|
|
if (tp != NULL)
|
|
clist_alloc_cblocks(&tp->t_outq,
|
|
ifp->if_mtu + SLIP_HIWAT,
|
|
ifp->if_mtu + SLIP_HIWAT);
|
|
}
|
|
break;
|
|
|
|
default:
|
|
error = EINVAL;
|
|
}
|
|
splx(s);
|
|
return (error);
|
|
}
|
|
|
|
static void
|
|
sl_keepalive(chan)
|
|
void *chan;
|
|
{
|
|
struct sl_softc *sc = chan;
|
|
|
|
if (sc->sc_keepalive) {
|
|
if (sc->sc_flags & SC_KEEPALIVE)
|
|
pgsignal (sc->sc_ttyp->t_pgrp, SIGURG, 1);
|
|
else
|
|
sc->sc_flags |= SC_KEEPALIVE;
|
|
timeout(sl_keepalive, sc, sc->sc_keepalive);
|
|
} else {
|
|
sc->sc_flags &= ~SC_KEEPALIVE;
|
|
untimeout(sl_keepalive, sc);
|
|
}
|
|
}
|
|
|
|
static void
|
|
sl_outfill(chan)
|
|
void *chan;
|
|
{
|
|
struct sl_softc *sc = chan;
|
|
register struct tty *tp = sc->sc_ttyp;
|
|
int s;
|
|
|
|
if (sc->sc_outfill && tp != NULL) {
|
|
if (sc->sc_flags & SC_OUTWAIT) {
|
|
s = splimp ();
|
|
++sc->sc_if.if_obytes;
|
|
(void) putc(FRAME_END, &tp->t_outq);
|
|
(*tp->t_oproc)(tp);
|
|
splx (s);
|
|
} else
|
|
sc->sc_flags |= SC_OUTWAIT;
|
|
timeout(sl_outfill, sc, sc->sc_outfill);
|
|
} else {
|
|
sc->sc_flags &= ~SC_OUTWAIT;
|
|
untimeout(sl_outfill, sc);
|
|
}
|
|
}
|
|
|
|
#endif
|