ftp.nice.ch/pub/next/connectivity/protocol/GateKeeper.3.0.Beta.4.s.tar.gz#/GateKeeper.3.0.Beta.4.s/ppp/NeXT/bpf/bpf.c

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/*-
 * Copyright (c) 1990-1993 The Regents of the University of California.
 * All rights reserved.
 *
 * This code is derived from the Stanford/CMU enet packet filter,
 * (net/enet.c) distributed as part of 4.3BSD, and code contributed
 * to Berkeley by Steven McCanne and Van Jacobson both of Lawrence
 * Berkeley Laboratory.
 *
 * 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.
 *
 *	@(#)bpf.c	7.5 (Berkeley) 7/15/91
 *
 * static char rcsid[] =
 * "$Id: bpf.c,v 1.2 1996/10/08 00:16:43 perkins Exp $";
 */

/* #include "bpfilter.h" */

#if NBPFILTER > 0

#if BSD >= 199207
#include <sys/cdefs.h>		/* get definition for inline */
#define MIN min			/* use min() from libkern.h */
#else
#define inline
#endif

#include <sys/param.h>
#include <sys/systm.h>
/*  #include <sys/mbuf.h> */
#include "netbuf.h"
#include <sys/buf.h>
#include <sys/time.h>
#include <sys/proc.h>
#include <machine/user.h>
#include <sys/ioctl.h>
/*#include <sys/map.h> */

#include <sys/file.h>
#if defined(sparc) && !defined(NeXT) && BSD < 199103
#include <sys/stream.h>
#endif
#include <sys/tty.h>
#include <sys/uio.h>

#include <sys/protosw.h>
#include <sys/socket.h>
#include <net/if.h>

#include "bpf.h"
#include "bpfdesc.h"

#include <sys/errno.h>
#include <sys/kernel.h>

#if defined(m68k)
#import "../spl.h"
#else
#import <kernserv/machine/spl.h>
#endif
#include <kernserv/prototypes.h>
#include <kernserv/kern_server_types.h>

kern_server_t instance;


/*
 * Older BSDs don't have kernel malloc.
 */
#if BSD < 199103

/*extern bcopy(); */
static caddr_t bpf_alloc();
#include "bpf_compat.h"
/*#define BPF_BUFSIZE (MCLBYTES-8)  */
#define BPF_BUFSIZE 4096
#define UIOMOVE(cp, len, code, uio) uiomove(cp, len, code, uio)
#else
#define BPF_BUFSIZE 4096
#define UIOMOVE(cp, len, code, uio) uiomove(cp, len, uio)
#endif

#define PRINET  26			/* interruptible */

/*
 * The default read buffer size is patchable.
 */
int bpf_bufsize = BPF_BUFSIZE;

/*
 *  bpf_iflist is the list of interfaces; each corresponds to an ifnet
 *  bpf_dtab holds the descriptors, indexed by minor device #
 */
struct bpf_if	*bpf_iflist;
struct bpf_d	bpf_dtab[NBPFILTER];

static void	bpf_ifname();
static void	catchpacket();
static void	bpf_freed();
static int	bpf_setif();
static int	bpf_allocbufs();

/*
 * Attach file to the bpf interface, i.e. make d listen on bp.
 * Must be called at splimp.
 */
static void
bpf_attachd(d, bp)
	struct bpf_d *d;
	struct bpf_if *bp;
{
	/*
	 * Point d at bp, and add d to the interface's list of listeners.
	 * Finally, point the driver's bpf cookie at the interface so
	 * it will divert packets to bpf.
	 */
	d->bd_bif = bp;
	d->bd_next = bp->bif_dlist;
	bp->bif_dlist = d;

	*bp->bif_driverp = bp; 
}

/*
 * Detach a file from its interface.
 */
static void
bpf_detachd(d)
	struct bpf_d *d;
{
	struct bpf_d **p;
	struct bpf_if *bp;

	bp = d->bd_bif;
	/*
	 * Check if this descriptor had requested promiscuous mode.
	 * If so, turn it off.
	 */
	if (d->bd_promisc) {
		d->bd_promisc = 0;
		if (bpfifpromisc(bp->bif_ifp, 0))
			/*
			 * Something is really wrong if we were able to put
			 * the driver into promiscuous mode, but can't
			 * take it out.
			 */
			IOLog("bpf: ifpromisc failed");
	}
	/* Remove d from the interface's descriptor list. */
	p = &bp->bif_dlist;
	while (*p != d) {
		p = &(*p)->bd_next;
		if (*p == 0)
			panic("bpf_detachd: descriptor not in list");
	}
	*p = (*p)->bd_next;
	if (bp->bif_dlist == 0)
		/*
		 * Let the driver know that there are no more listeners.
		 */
		*d->bd_bif->bif_driverp = 0;
	d->bd_bif = 0;
}


/*
 * Mark a descriptor free by making it point to itself.
 * This is probably cheaper than marking with a constant since
 * the address should be in a register anyway.
 */
#define D_ISFREE(d) ((d) == (d)->bd_next)
#define D_MARKFREE(d) ((d)->bd_next = (d))
#define D_MARKUSED(d) ((d)->bd_next = 0)


/*
 * Open ethernet device.  Returns ENXIO for illegal minor device number,
 * EBUSY if file is open by another process.
 */
/* ARGSUSED */
int
bpfopen(dev, flag)
	dev_t dev;
	int flag;
{
	register struct bpf_d *d;

	if (minor(dev) >= NBPFILTER)
		return (ENXIO);
	/*
	 * Each minor can be opened by only one process.  If the requested
	 * minor is in use, return EBUSY.
	 */
	d = &bpf_dtab[minor(dev)];
	if (!D_ISFREE(d))
		return (EBUSY);

	/* Mark "free" and do most initialization. */
	bzero((char *)d, sizeof(*d));
	d->bd_bufsize = bpf_bufsize;

	return (0);
}

/*
 * Close the descriptor by detaching it from its interface,
 * deallocating its buffers, and marking it free.
 */
/* ARGSUSED */
int
bpfclose(dev, flag)
	dev_t dev;
	int flag;
{
	register struct bpf_d *d = &bpf_dtab[minor(dev)];
	register int s;

	s = splimp();
	if (d->bd_bif)
		bpf_detachd(d);
	splx(s);
	bpf_freed(d);

	return (0);
}

/*
 * Support for SunOS, which does not have tsleep.
 */
#if BSD < 199103
static
bpf_timeout(arg)
	caddr_t arg;
{
	struct bpf_d *d = (struct bpf_d *)arg;
	d->bd_timedout = 1;
	wakeup(arg);
}

#define BPF_SLEEP(chan, pri, s, t) bpf_sleep((struct bpf_d *)chan)

int
bpf_sleep(d)
	register struct bpf_d *d;
{
	register int rto = d->bd_rtout;
	register int st;

	if (rto != 0) {
		d->bd_timedout = 0;
		timeout(bpf_timeout, (caddr_t)d, rto);
	}
/*	st = sleep((caddr_t)d, PRINET|PCATCH); */
	st = sleep((caddr_t)d, TTIPRI);
	if (rto != 0) {
		if (d->bd_timedout == 0)
		  {
		    untimeout(bpf_timeout, (caddr_t)d);
		  }
		else if (st == 0)
		    return EWOULDBLOCK;
	}
	return (st != 0) ? EINTR : 0;
}
#else
#define BPF_SLEEP tsleep
#endif

/*
 * Rotate the packet buffers in descriptor d.  Move the store buffer
 * into the hold slot, and the free buffer into the store slot.
 * Zero the length of the new store buffer.
 */
#define ROTATE_BUFFERS(d) \
	(d)->bd_hbuf = (d)->bd_sbuf; \
	(d)->bd_hlen = (d)->bd_slen; \
	(d)->bd_sbuf = (d)->bd_fbuf; \
	(d)->bd_slen = 0; \
	(d)->bd_fbuf = 0;
/*
 *  bpfread - read next chunk of packets from buffers
 */
int
bpfread(dev, uio)
	dev_t dev;
	register struct uio *uio;
{
	register struct bpf_d *d = &bpf_dtab[minor(dev)];
	int error;
	int s;

	/*
	 * Restrict application to use a buffer the same size as
	 * as kernel buffers.
	 */

	if (uio->uio_resid != d->bd_bufsize)
	  {
	    IOLog ("BPF error: Application buffer not same size as kernel buffer\n");
	    return (EINVAL);
	  }

	s = splimp();
	/*
	 * If the hold buffer is empty, then do a timed sleep, which
	 * ends when the timeout expires or when enough packets
	 * have arrived to fill the store buffer.
	 */
	while (d->bd_hbuf == 0) {
#if BSD < 199103
/*		if (uio->uio_fmode & (FNONBIO|FNDELAY)) */
		if ((uio->uio_fmode & FNDELAY) && 0)       /* +++ SJP fails under 3.3*/
#else
		/*XXX won't compile as is: ioflag is 3rd arg*/
		if (ioflag & IO_NDELAY)
#endif
		{
			if (d->bd_slen == 0) {
				splx(s);
				return (EWOULDBLOCK);
			}
			ROTATE_BUFFERS(d);
			break;
		}
		if (d->bd_immediate && d->bd_slen != 0) {
			/*
			 * A packet(s) either arrived since the previous
			 * read or arrived while we were asleep.
			 * Rotate the buffers and return what's here.
			 */
			ROTATE_BUFFERS(d);
			break;
		}
		error = BPF_SLEEP((caddr_t)d, PRINET|PCATCH, "bpf",
				  d->bd_rtout);
		if (error != 0) {
			if (error == EWOULDBLOCK) {
				/*
				 * On a timeout, return what's in the buffer,
				 * which may be nothing.  If there is something
				 * in the store buffer, we can do a rotation.
				 */
				if (d->bd_hbuf)
					/*
					 * We filled up the buffer in between
					 * getting the timeout and arriving
					 * here, so we don't need to rotate.
					 */
					break;
				
				if (d->bd_slen == 0) {
					splx(s);
					return (0);
				}
				ROTATE_BUFFERS(d);
				break;
			}
			splx(s);
			return (error);
		}
	}
	/*
	 * At this point, we know we have something in the hold slot.
	 */
	splx(s);

	/*
	 * Move data from hold buffer into user space.
	 * We know the entire buffer is transferred since
	 * we checked above that the read buffer is bpf_bufsize bytes.
	 */
/*	error = UIOMOVE(d->bd_hbuf, d->bd_hlen, UIO_READ, uio); */
	error = UIOMOVE(d->bd_hbuf, d->bd_hlen, UIO_READ, uio); 

	s = splimp();
	d->bd_fbuf = d->bd_hbuf;
	d->bd_hbuf = 0;
	d->bd_hlen = 0;
	splx(s);

	return (error);
}


/*
 * If there are processes sleeping on this descriptor, wake them up.
 */
static inline void
bpf_wakeup(d)
	register struct bpf_d *d;
{
	wakeup((caddr_t)d);
#if BSD >= 199103
	selwakeup(&d->bd_sel);
	/* XXX */
	d->bd_sel.si_pid = 0;
#else
	if (d->bd_selproc) {
		selwakeup(d->bd_selproc, (int)d->bd_selcoll);
		d->bd_selcoll = 0;
		d->bd_selproc = 0;
	}
#endif
}

int
bpfwrite(dev, uio)
	dev_t dev;
	struct uio *uio;
{
	register struct bpf_if *bp = bpf_dtab[minor(dev)].bd_bif;
/*	register struct ifnet *ifp; */
	register netif_t ifp; 
/*	register struct mbuf *m; */
	register NETBUF_T m;
	register u_int len, hlen;
	register int error, s;
	struct sockaddr dst;

	if (bp == 0)
		return (ENXIO);

	/*
	 * Build a sockaddr based on the data link layer type.
	 * The AF_UNSPEC kludge allows us to hand the link level
	 * header to the driver via the sockaddr.  This isn't
	 * very clean.  It would be better if AF_UNSPEC meant that
	 * the driver shouldn't bother with encapsulation (i.e., the
	 * link header is already in the mbuf).  The code here is
	 * structured this way, then things are kludged back before
	 * calling if_output.
	 *
	 * NOTE:  When adding new link layers make sure the driver supports
	 *	  AF_UNSPEC and that the link header can fit in the sa_data
	 *	  field of a sockaddr.
	 */
	switch (bp->bif_dlt) {

	case DLT_SLIP:
		dst.sa_family = AF_INET;
		hlen = 0;
		break;

	case DLT_PPP:
		dst.sa_family = AF_INET;
		hlen = 4;
		break;

	case DLT_EN10MB:
		dst.sa_family = AF_UNSPEC;
		/* 6(dst)+6(src)+2(type) */
		hlen = 14;
		break;

#ifdef notyet
	case DLT_FDDI:
		/* XXX can't fit an fddi header in a struct sockaddr */
		dst.sa_family = AF_UNSPEC;
		/* 4(FORMAC)+6(dst)+6(src)+3(LLC)+5(SNAP) */
		hlen = 24;
		break;
#endif

	case DLT_NULL:
		dst.sa_family = AF_UNSPEC;
		hlen = 0;
		break;

	default:
		return (EIO);
	}
	ifp = bp->bif_ifp;
	len = uio->uio_resid;
	/*
	 * If we didn't get enough for the link level header, or we
	 * exceed the interface's mtu, return an error.
	 */
/*	if (len < hlen || len - hlen > ifp->if_mtu) */
	if (len < hlen || len - hlen > if_mtu(ifp))
		return (EMSGSIZE);

	/*
	 * XXX Bail if it won't fit in a single mbuf.
	 */
/*
	if (len > MCLBYTES)
		return (EIO);
*/
/*	MGET(m, M_WAIT, MT_DATA); */
	m = NB_ALLOC(len + 4);  /* MRLKEN */

	if (m == 0)
		return (ENOBUFS);
	NB_SHRINK_TOP(m, MRKLEN);
/*
	if (len > MLEN) {
#if BSD >= 199103
		MCLGET(m, M_WAIT);
		if ((m->m_flags & M_EXT) == 0)
#else
		MCLGET(m);
		if (m->m_len != MCLBYTES)
#endif
		{
			m_freem(m);
			return (ENOBUFS);
		}
	}
*/
	/*
	 * Move the whole packet, including the data link header, 
	 * into the mbuf.  Then, copy the link header back out of the
	 * packet into the sockaddr.  Finally, strip the link header
	 * from the front of the mbuf.
	 */
	error = UIOMOVE(mtod(m, caddr_t), len, UIO_WRITE, uio);
	if (error) {
/*		m_freem(m); */
		NB_FREE(m);
		return (error);
	}
	if (hlen > 0) {
		bcopy(mtod(m, caddr_t), dst.sa_data, hlen);
/*
#if BSD >= 199103
		m->m_data += hlen;
#else
		m->m_off += hlen;
#endif
*/
		NB_SHRINK_TOP(m, hlen);
		len -= hlen;
	}
/*	m->m_len = len; */
	s = splnet();
/*
#if BSD >= 199103
	error = (*ifp->if_output)(ifp, m, &dst, (struct rtentry *)0);
#else
	error = (*ifp->if_output)(ifp, m, &dst);
#endif
*/
	error = if_output(ifp, NB_TO_nb(m), &dst);
	splx(s);
	/*
	 * The driver frees the mbuf.
	 */
	return (error);
}

/*
 * Reset a descriptor by flushing its packet buffer and clearing the
 * receive and drop counts.  Should be called at splimp.
 */
static void
reset_d(d)
	struct bpf_d *d;
{
	if (d->bd_hbuf) {
		/* Free the hold buffer. */
		d->bd_fbuf = d->bd_hbuf;
		d->bd_hbuf = 0;
	}
	d->bd_slen = 0;
	d->bd_hlen = 0;
	d->bd_rcount = 0;
	d->bd_dcount = 0;
}

/*
 *  FIONREAD		Check for read packet available.
 *  SIOCGIFADDR		Get interface address - convenient hook to driver.
 *  BIOCGBLEN		Get buffer len [for read()].
 *  BIOCSETF		Set ethernet read filter.
 *  BIOCFLUSH		Flush read packet buffer.
 *  BIOCPROMISC		Put interface into promiscuous mode.
 *  BIOCGDLT		Get link layer type.
 *  BIOCGETIF		Get interface name.
 *  BIOCSETIF		Set interface.
 *  BIOCSRTIMEOUT	Set read timeout.
 *  BIOCGRTIMEOUT	Get read timeout.
 *  BIOCGSTATS		Get packet stats.
 *  BIOCIMMEDIATE	Set immediate mode.
 *  BIOCVERSION		Get filter language version.
 */
/* ARGSUSED */
int
bpfioctl(dev, cmd, addr, flag)
	dev_t dev;
	int cmd;
	caddr_t addr;
	int flag;
{
	register struct bpf_d *d = &bpf_dtab[minor(dev)];
	int s, error = 0;


	if (minor(dev) >= NBPFILTER)
	  {
	    IOLog("Warning, ioctl called with bad minor device (%d)\n",
		  minor(dev));
	    return EINVAL;
	  }
	
	switch (cmd) {

	default:
	  printf("Default\n");
		error = EINVAL;
		break;

	case FIONBIO:
	case FIOASYNC:
	  printf("FIOBIO/FIOASYNC\n");
		break;

	/*
	 * Check for read packet available.
	 */
	case FIONREAD:
		{

			int n;
			printf("FIONREAD\n");

			s = splimp();
			n = d->bd_slen;
			if (d->bd_hbuf)
				n += d->bd_hlen;
			splx(s);

			*(int *)addr = n;
			break;
		}

	case SIOCGIFADDR:
		{

/*			struct ifnet *ifp; */
			netif_t ifp;
			printf("SIOCGIFADDR\n");
			if (d->bd_bif == 0)
				error = EINVAL;
			else {
				ifp = d->bd_bif->bif_ifp;
				printf("Fix this ioctl %s %d\n", __FILE__, __LINE__);
				error = if_ioctl(ifp, cmd, addr);
			}
			break;
		}

	/*
	 * Get buffer len [for read()].
	 */
	case BIOCGBLEN:
		*(u_int *)addr = d->bd_bufsize;
		break;

	/*
	 * Set buffer length.
	 */
	case BIOCSBLEN:
	  printf("BIOSBLEN\n");

#if BSD < 199103
		error = EINVAL;
#else
		if (d->bd_bif != 0)
			error = EINVAL;
		else {
			register u_int size = *(u_int *)addr;

			if (size > BPF_MAXBUFSIZE)
				*(u_int *)addr = size = BPF_MAXBUFSIZE;
			else if (size < BPF_MINBUFSIZE)
				*(u_int *)addr = size = BPF_MINBUFSIZE;
			d->bd_bufsize = size;
		}
#endif
		break;

	/*
	 * Set link layer read filter.
	 */
	case BIOCSETF:
		error = bpf_setf(d, (struct bpf_program *)addr);
		break;

	/*
	 * Flush read packet buffer.
	 */
	case BIOCFLUSH:
	  printf("BIOCFLUSH\n");
		s = splimp();
		reset_d(d);
		splx(s);
		break;

	/*
	 * Put interface into promiscuous mode.
	 */
	case BIOCPROMISC:
		if (d->bd_bif == 0) {
			/*
			 * No interface attached yet.
			 */
			error = EINVAL;
			break;
		}
		s = splimp();
		if (d->bd_promisc == 0) {
			error = bpfifpromisc(d->bd_bif->bif_ifp, 1);
			if (error == 0)
				d->bd_promisc = 1;
		}
		splx(s);
		break;

	/*
	 * Get device parameters.
	 */
	case BIOCGDLT:
		if (d->bd_bif == 0)
			error = EINVAL;
		else
		    *(u_int *)addr = d->bd_bif->bif_dlt;
		break;

	/*
	 * Set interface name.
	 */
	case BIOCGETIF:
	  printf("BIOCGETIF\n");
		if (d->bd_bif == 0)
			error = EINVAL;
		else
			bpf_ifname(d->bd_bif->bif_ifp, (struct ifreq *)addr);
		break;

	/*
	 * Set interface.
	 */
	case BIOCSETIF:
		error = bpf_setif(d, (struct ifreq *)addr);
		break;

	/*
	 * Set read timeout.
	 */
	case BIOCSRTIMEOUT:
		{
			struct timeval *tv = (struct timeval *)addr;
			u_long msec;

			/* Compute number of milliseconds. */
			msec = tv->tv_sec * 1000 + tv->tv_usec / 1000;
			/* Scale milliseconds to ticks.  Assume hard
			   clock has millisecond or greater resolution
			   (i.e. tick >= 1000).  For 10ms hardclock,
			   tick/1000 = 10, so rtout<-msec/10. */
			d->bd_rtout = msec / (tick / 1000);
			break;
		}

	/*
	 * Get read timeout.
	 */
	case BIOCGRTIMEOUT:
		{
			struct timeval *tv = (struct timeval *)addr;
			u_long msec = d->bd_rtout;

	  printf("BIOCGRTIMEOUT\n");
			msec *= tick / 1000;
			tv->tv_sec = msec / 1000;
			tv->tv_usec = msec % 1000;
			break;
		}

	/*
	 * Get packet stats.
	 */
	case BIOCGSTATS:
		{
			struct bpf_stat *bs = (struct bpf_stat *)addr;
			bs->bs_recv = d->bd_rcount;
			bs->bs_drop = d->bd_dcount;
			break;
		}

	/*
	 * Set immediate mode.
	 */
	case BIOCIMMEDIATE:
	  printf("BIOCIMMEDIATE\n");
		d->bd_immediate = *(u_int *)addr;
		break;

	case BIOCVERSION:
		{
			struct bpf_version *bv = (struct bpf_version *)addr;
			bv->bv_major = BPF_MAJOR_VERSION;
			bv->bv_minor = BPF_MINOR_VERSION;
			break;
		}
#ifdef BPFPROF
	case BIOCPROFRESET:
		bprof_reset();
		break;

	case BIOCPROFGET:
		bprof_get((struct bprof_info *)addr);
		break;
#endif

#ifdef NeXT
	case BIOCATTACH:
	  {
	    struct bpf_attachargs *atarg = (struct bpf_attachargs *)addr;
	    extern void bpfattach();
	    bpfattach(atarg->driverp, (netif_t) atarg->ifp, atarg->dlt, atarg->hdrlen);
	    break;
	  }

	case BIOCGFNS:
	  {
	    struct bpf_fns *fnargs = (struct bpf_fns *)addr;
	    extern void bpf_tap();
	    fnargs->tapfn = bpf_tap;
	    break;
	  }
#endif
	}

	return (error);
}

/*
 * Set d's packet filter program to fp.  If this file already has a filter,
 * free it and replace it.  Returns EINVAL for bogus requests.
 */
int
bpf_setf(d, fp)
	struct bpf_d *d;
	struct bpf_program *fp;
{
	struct bpf_insn *fcode, *old;
	u_int flen, size;
	int s;

	old = d->bd_filter;
	if (fp->bf_insns == 0) {
		if (fp->bf_len != 0)
			return (EINVAL);
		s = splimp();
		d->bd_filter = 0;
		reset_d(d);
		splx(s);
		if (old != 0)
			BPFfree((caddr_t)old, M_DEVBUF);
		return (0);
	}
	flen = fp->bf_len;
	if (flen > BPF_MAXINSNS)
		return (EINVAL);

	size = flen * sizeof(*fp->bf_insns);
	fcode = (struct bpf_insn *)BPFmalloc(size, M_DEVBUF, M_WAITOK);
	if (fcode == 0)
		return (ENOMEM);
	if (copyin((caddr_t)fp->bf_insns, (caddr_t)fcode, size) == 0 &&
	    bpf_validate(fcode, (int)flen)) {
		s = splimp();
		d->bd_filter = fcode;
		reset_d(d);
		splx(s);
		if (old != 0)
			BPFfree((caddr_t)old, M_DEVBUF);

		return (0);
	}
	BPFfree((caddr_t)fcode, M_DEVBUF);
	return (EINVAL);
}

/*
 * Detach a file from its current interface (if attached at all) and attach
 * to the interface indicated by the name stored in ifr.
 * Return an errno or 0.
 */
static int
bpf_setif(d, ifr)
	struct bpf_d *d;
	struct ifreq *ifr;
/*	netif_t ifr; */
{
	struct bpf_if *bp;
	char *cp;
	int unit, s, error;

	/*
	 * Separate string into name part and unit number.  Put a null
	 * byte at the end of the name part, and compute the number.
	 * If the a unit number is unspecified, the default is 0,
	 * as initialized above.  XXX This should be common code.
	 */
	unit = 0;
	cp = ifr->ifr_name;
/*	cp = if_name(ifr); */
	cp[sizeof(ifr->ifr_name) - 1] = '\0'; 
/*	cp[strlen(if_name(ifr)) - 1] = '\0'; */
	
	while (*cp++) {
		if (*cp >= '0' && *cp <= '9') {
			unit = *cp - '0';
			*cp++ = '\0';
			while (*cp)
				unit = 10 * unit + *cp++ - '0';
			break;
		}
	}

	/*
	 * Look through attached interfaces for the named one.
	 */
	for (bp = bpf_iflist; bp != 0; bp = bp->bif_next) {
/*		struct ifnet *ifp = bp->bif_ifp;  */
		netif_t ifp = bp->bif_ifp; 

		if (ifp == 0 || unit != if_unit(ifp)
/*		    || strcmp(ifp->if_name, ifr->ifr_name) != 0)  */
		    || strcmp(if_name(ifp), ifr->ifr_name) != 0)
			continue;
		/*
		 * We found the requested interface.
		 * If it's not up, return an error.
		 * Allocate the packet buffers if we need to.
		 * If we're already attached to requested interface,
		 * just flush the buffer.
		 */
/*		if ((ifp->if_flags & IFF_UP) == 0)  */
		if ((if_flags(ifp) & IFF_UP) == 0)
			return (ENETDOWN);

		if (d->bd_sbuf == 0) {
			error = bpf_allocbufs(d); 
			if (error != 0)
				return (error);
		}
		s = splimp();
		

		if (bp != d->bd_bif) {
		  
		  if (d->bd_bif)
		    /*
		     * Detach if attached to something else.
		     */
		    bpf_detachd(d);
		  bpf_attachd(d, bp);
		}
		reset_d(d);
		splx(s);
		return (0);
	}


	/* Not found. */
	return (ENXIO);
}

/*
 * Convert an interface name plus unit number of an ifp to a single
 * name which is returned in the ifr.
 */
static void
bpf_ifname(ifp, ifr)
/*
	struct ifnet *ifp;
	struct ifreq *ifr;
*/
	netif_t ifp;
	netif_t ifr;

{
/*
	char *s = ifp->if_name;
	char *d = ifr->ifr_name;
*/
	char *s = if_name(ifp);
	char *d = if_name(ifr);

	while (*d++ = *s++)
		continue;
	/* XXX Assume that unit number is less than 10. */
/*	*d++ = ifp->if_unit + '0'; */
	*d++ = if_unit(ifp) + '0';
	*d = '\0';
}

/*
 * The new select interface passes down the proc pointer; the old select
 * stubs had to grab it out of the user struct.  This glue allows either case.
 */
#if BSD >= 199103
#define bpf_select bpfselect
#else
int
bpfselect(dev, rw)
	register dev_t dev;
	int rw;
{
	
  return (bpf_select(dev, rw, getproc()));
}
#endif

/*
 * Support for select() system call
 * Inspired by the code in tty.c for the same purpose.
 *
 * Return true iff the specific operation will not block indefinitely.
 * Otherwise, return false but make a note that a selwakeup() must be done.
 */
int
bpf_select(dev, rw, p)
	register dev_t dev;
	int rw;
	struct proc *p;
{
	register struct bpf_d *d;
	register int s;

	if (rw != FREAD)
		return (0);

	d = &bpf_dtab[minor(dev)];

	s = splimp();
	if (d->bd_hlen != 0 || (d->bd_immediate && d->bd_slen != 0)) {
		/*
		 * There is data waiting.
		 */
		splx(s);
		return (1);
	}
#if BSD >= 199103
	selrecord(p, &d->bd_sel);
#else
	/*
	 * No data ready.  If there's already a select() waiting on this
	 * minor device then this is a collision.  This shouldn't happen
	 * because minors really should not be shared, but if a process
	 * forks while one of these is open, it is possible that both
	 * processes could select on the same descriptor.
	 */
/*	if (d->bd_selproc && d->bd_selproc->p_wchan == (caddr_t)&selwait) */
	if (d->bd_selproc)
		d->bd_selcoll = 1;
	else
		d->bd_selproc = p;
#endif
	splx(s);
	return (0);
}

/*
 * Incoming linkage from device drivers.  Process the packet pkt, of length
 * pktlen, which is stored in a contiguous buffer.  The packet is parsed
 * by each process' filter, and if accepted, stashed into the corresponding
 * buffer.
 */
void
bpf_tap(arg, pkt, pktlen)
     caddr_t arg;
#ifndef NETBUF_PROXY
     register u_char *pkt;
#else
     register NETBUF_T pkt;
#endif
     register u_int pktlen;
{
  struct bpf_if *bp;
  register struct bpf_d *d;
  register u_int slen;
  
  /*
   * Note that the ipl does not have to be raised at this point.
   * The only problem that could arise here is that if two different
   * interfaces shared any data.  This is not the case.
   */
  bp = (struct bpf_if *)arg;
  for (d = bp->bif_dlist; d != 0; d = d->bd_next)
    {
      ++d->bd_rcount;
#ifndef NETBUF_PROXY
      slen = bpf_filter(d->bd_filter, pkt, pktlen, pktlen);
#else
      if (pkt->pktinfo.flags & NBFLAG_INCOMING)
	slen = bpf_filter(d->bd_filter, NB_MAP(pkt),
			  NB_SIZE(pkt), NB_SIZE(pkt));
      else
	slen = bpf_filter(d->bd_filter, NB_MAP_ORIG(pkt),
			  NB_SIZE_ORIG(pkt), NB_SIZE_ORIG(pkt));
      
      
#endif
      if (slen != 0)
#ifndef NETBUF_PROXY
	catchpacket(d, pkt, pktlen, slen, bcopy);
#else
      if (pkt->pktinfo.flags & NBFLAG_INCOMING)
	catchpacket(d, pkt, NB_SIZE(pkt), slen, bcopy);
      else
	catchpacket(d, pkt, NB_SIZE_ORIG(pkt), slen, bcopy);
#endif
    }
}

/*
 * Copy data from an mbuf chain into a buffer.  This code is derived
 * from m_copydata in sys/uipc_mbuf.c.
 */
#if 0
static void
bpf_mcopy(src, dst, len)
	u_char *src;
	u_char *dst;
	register int len;
{
	register struct mbuf *m = (struct mbuf *)src;
	register unsigned count;

	while (len > 0) {
		if (m == 0)
			panic("bpf_mcopy");
		count = MIN(m->m_len, len);
		bcopy(mtod(m, caddr_t), (caddr_t)dst, count);
		m = m->m_next;
		dst += count;
		len -= count;
	}
}

/*
 * Incoming linkage from device drivers, when packet is in an mbuf chain.
 */
void
bpf_mtap(arg, m)
	caddr_t arg;
	struct mbuf *m;
{
	struct bpf_if *bp = (struct bpf_if *)arg;
	struct bpf_d *d;
	u_int pktlen, slen;
	struct mbuf *m0;

	pktlen = 0;
	for (m0 = m; m0 != 0; m0 = m0->m_next)
		pktlen += m0->m_len;

	for (d = bp->bif_dlist; d != 0; d = d->bd_next) {
		++d->bd_rcount;
		slen = bpf_filter(d->bd_filter, (u_char *)m, pktlen, 0);
		if (slen != 0)
			catchpacket(d, (u_char *)m, pktlen, slen, bpf_mcopy);
	}
}
#endif

/*
 * Move the packet data from interface memory (pkt) into the
 * store buffer.  Return 1 if it's time to wakeup a listener (buffer full),
 * otherwise 0.  cpfn is the routine called to do the actual data
 * transfer.  bcopy() is passed to catchpacket to copy contiguous chunks, while
 * bpf_mcopy() is passed to copy mbuf chains.  In the latter case,
 * pkt is really an mbuf.
 */
static void
catchpacket(d, pkt, pktlen, snaplen, cpfn)
	register struct bpf_d *d;
#ifndef NETBUF_PROXY
	register u_char *pkt;
#else
	register NETBUF_T pkt;
#endif
	register u_int pktlen, snaplen;
	register void (*cpfn)();
{
	register struct bpf_hdr *hp;
	register int totlen, curlen;
	register int hdrlen = d->bd_bif->bif_hdrlen;


	/*
	 * Figure out how many bytes to move.  If the packet is
	 * greater or equal to the snapshot length, transfer that
	 * much.  Otherwise, transfer the whole packet (unless
	 * we hit the buffer size limit).
	 */
	totlen = hdrlen + MIN(snaplen, pktlen);
	if (totlen > d->bd_bufsize)
		totlen = d->bd_bufsize;

	/*
	 * Round up the end of the previous packet to the next longword.
	 */
	curlen = BPF_WORDALIGN(d->bd_slen);
	if (curlen + totlen > d->bd_bufsize) {
		/*
		 * This packet will overflow the storage buffer.
		 * Rotate the buffers if we can, then wakeup any
		 * pending reads.
		 */
		if (d->bd_fbuf == 0) {
			/*
			 * We haven't completed the previous read yet,
			 * so drop the packet.
			 */
		  IOLog("bpf: Dropping packet\n");
			++d->bd_dcount;
			return;
		}
		ROTATE_BUFFERS(d);
		bpf_wakeup(d);
		curlen = 0;
	}
	else if (d->bd_immediate)
		/*
		 * Immediate mode is set.  A packet arrived so any
		 * reads should be woken up.
		 */
		bpf_wakeup(d);

	/*
	 * Append the bpf header.
	 */
	hp = (struct bpf_hdr *)(d->bd_sbuf + curlen);
#if BSD >= 199103
	microtime(&hp->bh_tstamp);
#elif defined(sun)
	uniqtime(&hp->bh_tstamp);
#else
	hp->bh_tstamp = time;
#endif

	hp->bh_datalen = pktlen;
	hp->bh_hdrlen = hdrlen;


#ifdef NETBUF_PROXY
	/*
	 * Append the extra timestamp and size info
	 */

	bcopy(&(pkt->pktinfo), &(hp->pktinfo), sizeof(bpf_encapsulater));
#endif

	/*
	 * Copy the packet data into the store buffer and update its length.
	 */
#ifndef NETBUF_PROXY
	(*cpfn)(pkt, (u_char *)hp + hdrlen, (hp->bh_caplen = totlen - hdrlen));
#else
	if (pkt->pktinfo.flags & NBFLAG_INCOMING)
	  (*cpfn)(NB_MAP(pkt), (u_char *)hp + hdrlen, (hp->bh_caplen = totlen - hdrlen));
	else
	  {
#if 0
	    IOLog("Outgoing of size %d (copy size %d): ", hp->bh_datalen, NB_SIZE_ORIG(pkt));
	    if (pkt->pktinfo.flags & NBFLAG_AC)
	      IOLog(" ac ");
	    if (pkt->pktinfo.flags & NBFLAG_PC)
	      IOLog(" pc ");
	    if (pkt->pktinfo.flags & NBFLAG_VJC)
	      IOLog(" vjc ");
	    if (pkt->pktinfo.flags & NBFLAG_CCP)
	      IOLog(" ccp ");
	    if (pkt->pktinfo.flags & NBFLAG_VJCINC)
	      IOLog(" vjcinc ");
	    if (pkt->pktinfo.flags & NBFLAG_CCPINC)
	      IOLog(" ccpinc ");
	    IOLog("\n");
#endif
	    
	    if (!NB_MAP_ORIG(pkt))
	      IOLog("Warning bad outgoing bpf packet\n");
	    else
	      (*cpfn)(NB_MAP_ORIG(pkt), (u_char *)hp + hdrlen, (hp->bh_caplen = totlen - hdrlen));
	  }
#endif
	d->bd_slen = curlen + totlen;
}

/* XXX */
#ifdef BPFPROF
u_char bpfbuf_b0[16 * 1024];
u_char bpfbuf_b1[16 * 1024];
int bpfbuf_inuse;
#endif

/*
 * Initialize all nonzero fields of a descriptor.
 */
static int
bpf_allocbufs(d)
	register struct bpf_d *d;
{
#ifdef BPFPROF
	if (bpfbuf_inuse == 0) {
		bpfbuf_inuse = 1;
		d->bd_bufsize = sizeof(bpfbuf_b0);
		d->bd_fbuf = (void *)bpfbuf_b0;
		d->bd_sbuf = (void *)bpfbuf_b1;
		d->bd_slen = 0;
		d->bd_hlen = 0;
		return (0);
	}
#endif

	d->bd_fbuf = (caddr_t)BPFmalloc(d->bd_bufsize, M_DEVBUF, M_WAITOK);
	if (d->bd_fbuf == 0)
		return (ENOBUFS);

	d->bd_sbuf = (caddr_t)BPFmalloc(d->bd_bufsize, M_DEVBUF, M_WAITOK);
	if (d->bd_sbuf == 0) {
		BPFfree(d->bd_fbuf, M_DEVBUF);
		return (ENOBUFS);
	}
	d->bd_slen = 0;
	d->bd_hlen = 0;
	return (0);
}

/*
 * Free buffers currently in use by a descriptor.
 * Called on close.
 */
static void
bpf_freed(d)
	register struct bpf_d *d;
{
#ifdef BPFPROF
	/* XXX */
	if (d->bd_sbuf == (void *)bpfbuf_b0 || d->bd_sbuf == (void*)bpfbuf_b1)
		bpfbuf_inuse = 0;
	else
#endif
	/*
	 * We don't need to lock out interrupts since this descriptor has
	 * been detached from its interface and it yet hasn't been marked
	 * free.
	 */
	if (d->bd_sbuf != 0) {
		BPFfree(d->bd_sbuf, M_DEVBUF);
		if (d->bd_hbuf != 0)
			BPFfree(d->bd_hbuf, M_DEVBUF);
		if (d->bd_fbuf != 0)
			BPFfree(d->bd_fbuf, M_DEVBUF);
	}
	if (d->bd_filter)
		BPFfree((caddr_t)d->bd_filter, M_DEVBUF);

	D_MARKFREE(d);
}

/*
 * Attach an interface to bpf.  driverp is a pointer to a (struct bpf_if *)
 * in the driver's softc; dlt is the link layer type; hdrlen is the fixed
 * size of the link header (variable length headers not yet supported).
 */
void
bpfattach(driverp, ifp, dlt, hdrlen)
	caddr_t *driverp;
/*	struct ifnet *ifp; */
	netif_t ifp;
	u_int dlt, hdrlen;
{
	struct bpf_if *bp;
	int i;
#if BSD < 199103
	static struct bpf_if bpf_ifs[NBPFILTER];
	static int bpfifno;

	bp = (bpfifno < NBPFILTER) ? &bpf_ifs[bpfifno++] : 0;
#else
	bp = (struct bpf_if *)BPFmalloc(sizeof(*bp), M_DEVBUF, M_DONTWAIT);
#endif
	if (bp == 0) {
	  IOLog ("Warning, bpfattach() out of interfaces...\n");
	  return;
	}

	bp->bif_dlist = 0;
	bp->bif_driverp = (struct bpf_if **)driverp;
	bp->bif_ifp = ifp;
	bp->bif_dlt = dlt;

	bp->bif_next = bpf_iflist;
	bpf_iflist = bp;

	*bp->bif_driverp = 0;

	/*
	 * Compute the length of the bpf header.  This is not necessarily
	 * equal to SIZEOF_BPF_HDR because we want to insert spacing such
	 * that the network layer header begins on a longword boundary (for
	 * performance reasons and to alleviate alignment restrictions).
	 */
	bp->bif_hdrlen = BPF_WORDALIGN(hdrlen + SIZEOF_BPF_HDR) - hdrlen;

	/*
	 * Mark all the descriptors free if this hasn't been done.
	 */
	if (!D_ISFREE(&bpf_dtab[0]))
		for (i = 0; i < NBPFILTER; ++i)
			D_MARKFREE(&bpf_dtab[i]);

/*	printf("bpf: %s%d attached\n", ifp->if_name, ifp->if_unit); */
	printf("bpf: %s%d attached.\n", if_name(ifp), if_unit(ifp));
}

#if BSD >= 199103
#if 0
/* XXX This routine belongs in net/if.c. */
/*
 * Set/clear promiscuous mode on interface ifp based on the truth value
 * of pswitch.  The calls are reference counted so that only the first
 * "on" request actually has an effect, as does the final "off" request.
 * Results are undefined if the "off" and "on" requests are not matched.
 */
int
ifpromisc(ifp, pswitch)
	struct ifnet *ifp;
	int pswitch;
{
	struct ifreq ifr;
	/*
	 * If the device is not configured up, we cannot put it in
	 * promiscuous mode.
	 */
	if ((ifp->if_flags & IFF_UP) == 0)
		return (ENETDOWN);

	if (pswitch) {
		if (ifp->if_pcount++ != 0)
			return (0);
		ifp->if_flags |= IFF_PROMISC;
	} else {
		if (--ifp->if_pcount > 0)
			return (0);
		ifp->if_flags &= ~IFF_PROMISC;
	}
	ifr.ifr_flags = ifp->if_flags;
	return ((*ifp->if_ioctl)(ifp, SIOCSIFFLAGS, (caddr_t)&ifr));
}
#endif
#endif

#if BSD < 199103
/*
 * Allocate some memory for bpf.  This is temporary SunOS support, and
 * is admittedly a hack.
 * If resources unavaiable, return 0.
 */

static caddr_t
bpf_alloc(size, canwait)
	register int size;
	register int canwait;
{
	register caddr_t mem;
	

	mem = (caddr_t) kalloc(size + sizeof(int));
	if (mem == 0)
	  return 0;
	*((int *)mem) = size + sizeof(int);
	((char *) mem) += sizeof(int);
	return mem;

/*
	if ((unsigned)size > (MCLBYTES-8))
		return 0;

	MGET(m, canwait, MT_DATA);
	if (m == 0)
		return 0;
	if ((unsigned)size > (MLEN-8)) {
		MCLGET(m);
		if (m->m_len != MCLBYTES) {
			m_freem(m);
			return 0;
		}
	}
	*mtod(m, struct mbuf **) = m;
	return mtod(m, caddr_t) + 8;
*/
}
#endif

#ifdef BPFPROF

#include <machine/clock.h>

struct bprof_rec nit_rec[BPFPROF_MAXLEN];
struct bprof_rec bpf_rec[BPFPROF_MAXLEN];

bprof_reset()
{
	register int i, s = splimp();
	/* let clock free run */
	COUNTER->limit14 = 0;
	for (i = 0; i < BPFPROF_MAXLEN; ++i) {
		bpf_rec[i].br_min = ~0;
		bpf_rec[i].br_max = 0;
		bpf_rec[i].br_cnt = 0;
		bpf_rec[i].br_tv.tv_sec = 0;
		bpf_rec[i].br_tv.tv_usec = 0;
		
		nit_rec[i].br_min = ~0;
		nit_rec[i].br_max = 0;
		nit_rec[i].br_cnt = 0;
		nit_rec[i].br_tv.tv_sec = 0;
		nit_rec[i].br_tv.tv_usec = 0;
	}
	splx(s);
}

/*
 * Find the time difference from between two values read from
 * the level 14 counter register, which is is free running mode.
 * We assume the values are less than 1 second or so apart.
 */
static int
xtime(b, a)
	register int b, a;
{
	int ua = (a & CTR_USEC_MASK) >> CTR_USEC_SHIFT;
	int ub = (b & CTR_USEC_MASK) >> CTR_USEC_SHIFT;
	int delta = ua - ub;
	if (delta < 0)
		/*
		 * The after time wrapped around, but the before
		 * time hadn't.  Add in a whole period.
		 */
		delta += (CTR_USEC_MASK >> CTR_USEC_SHIFT) + 1;
	return (delta);
}

/*
 * Add u microseconds (u < 1000000) to the timeval pointed to by p.
 */
tvaddu(p, d)
	register struct timeval *p;
	register int d;
{
	p->tv_usec += d;
	if (p->tv_usec >= 1000000) {
		p->tv_usec -= 1000000;
		++p->tv_sec;
	}
}

prof_gen(b, a, len, br)
	register int b, a, len;
	struct bprof_rec *br;
{
	register int d = xtime(b, a);
	if (len >= BPFPROF_MAXLEN)
		len = BPFPROF_MAXLEN - 1;
	br += len;
	++br->br_cnt;
	if (d > br->br_max)
		br->br_max = d;
	if (d < br->br_min)
		br->br_min = d;
	tvaddu(&br->br_tv, xtime(b, a));
}

prof_bpf(b, a, len)
	register int b, a, len;
{
	prof_gen(b, a, len, bpf_rec);
}

prof_nit(b, a, len)
	register int b, a, len;
{
	prof_gen(b, a, len, nit_rec);
}

bprof_get(ip)
	struct bprof_info *ip;
{
	(void)copyout((void *)nit_rec, (void *)ip->bi_nit, sizeof(nit_rec));
	(void)copyout((void *)bpf_rec, (void *)ip->bi_bpf, sizeof(bpf_rec));
}
#endif

#endif

These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Marcel Waldvogel and Netfuture.ch.