if_ppp.c

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Author : kn
Date : 2020-08-21 22:59:27
Hash : 0e70c421
Message : Leave default ifq_maxlen handling to ifq_init() Most clonable interface drivers (except bridge, enc, loop, pppx, switch, trunk and vlan) initialise the send queue's length to IFQ_MAXLEN during *_clone_create() even though ifq_init(), which is eventually called through if_attach(), does the same. Remove all early "ifq_set_maxlen(&ifq->if_snd, IFQ_MAXLEN);" lines to leave it to ifq_init() and have clonable drivers a tad more in sync. OK mvs
sys/net/if_ppp.c
/*	$OpenBSD: if_ppp.c,v 1.117 2020/08/21 22:59:27 kn Exp $	*/
/*	$NetBSD: if_ppp.c,v 1.39 1997/05/17 21:11:59 christos Exp $	*/

/*
 * if_ppp.c - Point-to-Point Protocol (PPP) Asynchronous driver.
 *
 * Copyright (c) 1984-2000 Carnegie Mellon University. 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. The name "Carnegie Mellon University" must not be used to
 *    endorse or promote products derived from this software without
 *    prior written permission. For permission or any legal
 *    details, please contact
 *      Office of Technology Transfer
 *      Carnegie Mellon University
 *      5000 Forbes Avenue
 *      Pittsburgh, PA  15213-3890
 *      (412) 268-4387, fax: (412) 268-7395
 *      tech-transfer@andrew.cmu.edu
 *
 * 4. Redistributions of any form whatsoever must retain the following
 *    acknowledgment:
 *    "This product includes software developed by Computing Services
 *     at Carnegie Mellon University (http://www.cmu.edu/computing/)."
 *
 * CARNEGIE MELLON UNIVERSITY DISCLAIMS ALL WARRANTIES WITH REGARD TO
 * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
 * AND FITNESS, IN NO EVENT SHALL CARNEGIE MELLON UNIVERSITY BE LIABLE
 * FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
 * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
 * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 *
 * Based on:
 *	@(#)if_sl.c	7.6.1.2 (Berkeley) 2/15/89
 *
 * 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.
 *
 * 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).
 * Converted to 4.3BSD Beta by Chris Torek.
 * Other changes made at Berkeley, based in part on code by Kirk Smith.
 *
 * Converted to 4.3BSD+ 386BSD by Brad Parker (brad@cayman.com)
 * Added VJ tcp header compression; more unified ioctls
 *
 * Extensively modified by Paul Mackerras (paulus@cs.anu.edu.au).
 * Cleaned up a lot of the mbuf-related code to fix bugs that
 * caused system crashes and packet corruption.  Changed pppstart
 * so that it doesn't just give up with a collision if the whole
 * packet doesn't fit in the output ring buffer.
 *
 * Added priority queueing for interactive IP packets, following
 * the model of if_sl.c, plus hooks for bpf.
 * Paul Mackerras (paulus@cs.anu.edu.au).
 */

/* from if_sl.c,v 1.11 84/10/04 12:54:47 rick Exp */
/* from NetBSD: if_ppp.c,v 1.15.2.2 1994/07/28 05:17:58 cgd Exp */

#include "ppp.h"
#if NPPP > 0

#define VJC
#define PPP_COMPRESS

#include <sys/param.h>
#include <sys/proc.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <sys/kernel.h>
#include <sys/systm.h>
#include <sys/time.h>
#include <sys/malloc.h>

#include <net/if.h>
#include <net/if_var.h>
#include <net/if_types.h>
#include <net/netisr.h>
#include <net/route.h>
#include <net/bpf.h>

#include <netinet/in.h>
#include <netinet/ip.h>

#include "bpfilter.h"

#ifdef VJC
#include <net/slcompress.h>
#endif

#include <net/ppp_defs.h>
#include <net/if_ppp.h>
#include <net/if_pppvar.h>

#ifdef PPP_COMPRESS
#define PACKETPTR	struct mbuf *
#include <net/ppp-comp.h>
#endif

static int	 pppsioctl(struct ifnet *, u_long, caddr_t);
static void	 ppp_requeue(struct ppp_softc *);
static void	 ppp_ccp(struct ppp_softc *, struct mbuf *m, int rcvd);
static void	 ppp_ccp_closed(struct ppp_softc *);
static void	 ppp_inproc(struct ppp_softc *, struct mbuf *);
static void	 pppdumpm(struct mbuf *m0);
static void	 ppp_ifstart(struct ifnet *ifp);
int		 ppp_clone_create(struct if_clone *, int);
int		 ppp_clone_destroy(struct ifnet *);

void		 ppp_pkt_list_init(struct ppp_pkt_list *, u_int);
int		 ppp_pkt_enqueue(struct ppp_pkt_list *, struct ppp_pkt *);
struct ppp_pkt	*ppp_pkt_dequeue(struct ppp_pkt_list *);
struct mbuf	*ppp_pkt_mbuf(struct ppp_pkt *);

/*
 * We steal two bits in the mbuf m_flags, to mark high-priority packets
 * for output, and received packets following lost/corrupted packets.
 */
#define M_ERRMARK	M_LINK0		/* steal a bit in mbuf m_flags */


#ifdef PPP_COMPRESS
/*
 * List of compressors we know about.
 */

extern struct compressor ppp_bsd_compress;
extern struct compressor ppp_deflate, ppp_deflate_draft;

struct compressor *ppp_compressors[] = {
#if DO_BSD_COMPRESS && defined(PPP_BSDCOMP)
	&ppp_bsd_compress,
#endif
#if DO_DEFLATE && defined(PPP_DEFLATE)
	&ppp_deflate,
	&ppp_deflate_draft,
#endif
	NULL
};
#endif /* PPP_COMPRESS */

LIST_HEAD(, ppp_softc) ppp_softc_list;
struct if_clone ppp_cloner =
    IF_CLONE_INITIALIZER("ppp", ppp_clone_create, ppp_clone_destroy);

/*
 * Called from boot code to establish ppp interfaces.
 */
void
pppattach(void)
{
	LIST_INIT(&ppp_softc_list);
	if_clone_attach(&ppp_cloner);
}

int
ppp_clone_create(struct if_clone *ifc, int unit)
{
	struct ppp_softc *sc;
	struct ifnet *ifp;

	sc = malloc(sizeof(*sc), M_DEVBUF, M_WAITOK|M_ZERO);
	sc->sc_unit = unit;
	ifp = &sc->sc_if;
	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 = PPP_MTU;
	sc->sc_if.if_flags = IFF_POINTOPOINT | IFF_MULTICAST;
	sc->sc_if.if_type = IFT_PPP;
	sc->sc_if.if_hdrlen = PPP_HDRLEN;
	sc->sc_if.if_ioctl = pppsioctl;
	sc->sc_if.if_output = pppoutput;
	sc->sc_if.if_start = ppp_ifstart;
	sc->sc_if.if_rtrequest = p2p_rtrequest;
	mq_init(&sc->sc_inq, IFQ_MAXLEN, IPL_NET);
	ppp_pkt_list_init(&sc->sc_rawq, IFQ_MAXLEN);
	if_attach(&sc->sc_if);
	if_alloc_sadl(&sc->sc_if);
#if NBPFILTER > 0
	bpfattach(&ifp->if_bpf, ifp, DLT_PPP, PPP_HDRLEN);
#endif
	NET_LOCK();
	LIST_INSERT_HEAD(&ppp_softc_list, sc, sc_list);
	NET_UNLOCK();

	return (0);
}

int
ppp_clone_destroy(struct ifnet *ifp)
{
	struct ppp_softc *sc = ifp->if_softc;

	if (sc->sc_devp != NULL)
		return (EBUSY);

	NET_LOCK();
	LIST_REMOVE(sc, sc_list);
	NET_UNLOCK();

	if_detach(ifp);

	free(sc, M_DEVBUF, 0);
	return (0);
}

/*
 * Allocate a ppp interface unit and initialize it.
 */
struct ppp_softc *
pppalloc(pid_t pid)
{
	int i;
	struct ppp_softc *sc;

	NET_LOCK();
	LIST_FOREACH(sc, &ppp_softc_list, sc_list) {
		if (sc->sc_xfer == pid) {
			sc->sc_xfer = 0;
			NET_UNLOCK();
			return sc;
		}
	}
	LIST_FOREACH(sc, &ppp_softc_list, sc_list) {
		if (sc->sc_devp == NULL)
			break;
	}
	NET_UNLOCK();
	if (sc == NULL)
		return NULL;

	sc->sc_flags = 0;
	sc->sc_mru = PPP_MRU;
	sc->sc_relinq = NULL;
	bzero((char *)&sc->sc_stats, sizeof(sc->sc_stats));
#ifdef VJC
	sc->sc_comp = malloc(sizeof(struct slcompress), M_DEVBUF, M_NOWAIT);
	if (sc->sc_comp)
		sl_compress_init(sc->sc_comp);
#endif
#ifdef PPP_COMPRESS
	sc->sc_xc_state = NULL;
	sc->sc_rc_state = NULL;
#endif /* PPP_COMPRESS */
	for (i = 0; i < NUM_NP; ++i)
		sc->sc_npmode[i] = NPMODE_ERROR;
	ml_init(&sc->sc_npqueue);
	sc->sc_last_sent = sc->sc_last_recv = getuptime();

	return sc;
}

/*
 * Deallocate a ppp unit.
 */
void
pppdealloc(struct ppp_softc *sc)
{
	struct ppp_pkt *pkt;

	NET_LOCK();
	if_down(&sc->sc_if);
	sc->sc_if.if_flags &= ~IFF_RUNNING;
	sc->sc_devp = NULL;
	sc->sc_xfer = 0;
	while ((pkt = ppp_pkt_dequeue(&sc->sc_rawq)) != NULL)
		ppp_pkt_free(pkt);
	mq_purge(&sc->sc_inq);
	ml_purge(&sc->sc_npqueue);
	m_freem(sc->sc_togo);
	sc->sc_togo = NULL;

#ifdef PPP_COMPRESS
	ppp_ccp_closed(sc);
	sc->sc_xc_state = NULL;
	sc->sc_rc_state = NULL;
#endif /* PPP_COMPRESS */
#if NBPFILTER > 0
	if (sc->sc_pass_filt.bf_insns != 0) {
		free(sc->sc_pass_filt.bf_insns, M_DEVBUF, 0);
		sc->sc_pass_filt.bf_insns = 0;
		sc->sc_pass_filt.bf_len = 0;
	}
	if (sc->sc_active_filt.bf_insns != 0) {
		free(sc->sc_active_filt.bf_insns, M_DEVBUF, 0);
		sc->sc_active_filt.bf_insns = 0;
		sc->sc_active_filt.bf_len = 0;
	}
#endif
#ifdef VJC
	if (sc->sc_comp != 0) {
		free(sc->sc_comp, M_DEVBUF, 0);
		sc->sc_comp = 0;
	}
#endif
	NET_UNLOCK();
}

/*
 * Ioctl routine for generic ppp devices.
 */
int
pppioctl(struct ppp_softc *sc, u_long cmd, caddr_t data, int flag,
    struct proc *p)
{
	int s, error, flags, mru, npx;
	u_int nb;
	struct ppp_option_data *odp;
	struct compressor **cp;
	struct npioctl *npi;
	time_t t;
#if NBPFILTER > 0
	struct bpf_program *bp, *nbp;
	struct bpf_insn *newcode, *oldcode;
	int newcodelen;
#endif
#ifdef	PPP_COMPRESS
	u_char ccp_option[CCP_MAX_OPTION_LENGTH];
#endif

	switch (cmd) {
	case FIONREAD:
		*(int *)data = mq_len(&sc->sc_inq);
		break;

	case PPPIOCGUNIT:
		*(int *)data = sc->sc_unit;	/* XXX */
		break;

	case PPPIOCGFLAGS:
		*(u_int *)data = sc->sc_flags;
		break;

	case PPPIOCSFLAGS:
		if ((error = suser(p)) != 0)
			return (error);
		flags = *(int *)data & SC_MASK;
#ifdef PPP_COMPRESS
		if (sc->sc_flags & SC_CCP_OPEN && !(flags & SC_CCP_OPEN))
			ppp_ccp_closed(sc);
#endif
		s = splnet();
		sc->sc_flags = (sc->sc_flags & ~SC_MASK) | flags;
		splx(s);
		break;

	case PPPIOCSMRU:
		if ((error = suser(p)) != 0)
			return (error);
		mru = *(int *)data;
		if (mru >= PPP_MRU && mru <= PPP_MAXMRU)
			sc->sc_mru = mru;
		break;

	case PPPIOCGMRU:
		*(int *)data = sc->sc_mru;
		break;

#ifdef VJC
	case PPPIOCSMAXCID:
		if ((error = suser(p)) != 0)
			return (error);
		if (sc->sc_comp)
			sl_compress_setup(sc->sc_comp, *(int *)data);
		break;
#endif

	case PPPIOCXFERUNIT:
		if ((error = suser(p)) != 0)
			return (error);
		sc->sc_xfer = p->p_p->ps_pid;
		break;

#ifdef PPP_COMPRESS
	case PPPIOCSCOMPRESS:
		if ((error = suser(p)) != 0)
			return (error);
		odp = (struct ppp_option_data *) data;
		nb = odp->length;
		if (nb > sizeof(ccp_option))
			nb = sizeof(ccp_option);
		if ((error = copyin(odp->ptr, ccp_option, nb)) != 0)
			return (error);
		 /* preliminary check on the length byte */
		if (ccp_option[1] < 2)
			return (EINVAL);
		for (cp = ppp_compressors; *cp != NULL; ++cp)
			if ((*cp)->compress_proto == ccp_option[0]) {
			/*
			 * Found a handler for the protocol - try to allocate
			 * a compressor or decompressor.
			 */
			error = 0;
			if (odp->transmit) {
				if (sc->sc_xc_state != NULL) {
					(*sc->sc_xcomp->comp_free)(
					    sc->sc_xc_state);
				}
				sc->sc_xcomp = *cp;
				sc->sc_xc_state = (*cp)->comp_alloc(ccp_option,
				    nb);
				if (sc->sc_xc_state == NULL) {
					if (sc->sc_flags & SC_DEBUG)
						printf(
						    "%s: comp_alloc failed\n",
						    sc->sc_if.if_xname);
					error = ENOBUFS;
				}
				s = splnet();
				sc->sc_flags &= ~SC_COMP_RUN;
				splx(s);
			} else {
				if (sc->sc_rc_state != NULL) {
					(*sc->sc_rcomp->decomp_free)(
					    sc->sc_rc_state);
				}
				sc->sc_rcomp = *cp;
				sc->sc_rc_state = (*cp)->decomp_alloc(
				    ccp_option, nb);
				if (sc->sc_rc_state == NULL) {
					if (sc->sc_flags & SC_DEBUG) {
						printf(
						    "%s: decomp_alloc failed\n",
						    sc->sc_if.if_xname);
					}
					error = ENOBUFS;
				}
				s = splnet();
				sc->sc_flags &= ~SC_DECOMP_RUN;
				splx(s);
			}
			return (error);
		}
		if (sc->sc_flags & SC_DEBUG) {
			printf("%s: no compressor for [%x %x %x], %x\n",
			    sc->sc_if.if_xname, ccp_option[0], ccp_option[1],
			    ccp_option[2], nb);
		}
		return (EINVAL);	/* no handler found */
#endif /* PPP_COMPRESS */

	case PPPIOCGNPMODE:
	case PPPIOCSNPMODE:
		npi = (struct npioctl *)data;
		switch (npi->protocol) {
		case PPP_IP:
			npx = NP_IP;
			break;
		default:
			return EINVAL;
		}
		if (cmd == PPPIOCGNPMODE) {
			npi->mode = sc->sc_npmode[npx];
		} else {
			if ((error = suser(p)) != 0)
				return (error);
			if (npi->mode != sc->sc_npmode[npx]) {
				sc->sc_npmode[npx] = npi->mode;
				if (npi->mode != NPMODE_QUEUE) {
					ppp_requeue(sc);
					(*sc->sc_start)(sc);
				}
			}
		}
		break;

	case PPPIOCGIDLE:
		t = getuptime();
		((struct ppp_idle *)data)->xmit_idle = t - sc->sc_last_sent;
		((struct ppp_idle *)data)->recv_idle = t - sc->sc_last_recv;
		break;

#if NBPFILTER > 0
	case PPPIOCSPASS:
	case PPPIOCSACTIVE:
		nbp = (struct bpf_program *) data;
		if ((unsigned) nbp->bf_len > BPF_MAXINSNS)
			return EINVAL;
		newcodelen = nbp->bf_len * sizeof(struct bpf_insn);
		if (nbp->bf_len != 0) {
			newcode = mallocarray(nbp->bf_len,
			    sizeof(struct bpf_insn), M_DEVBUF, M_WAITOK);
			if ((error = copyin((caddr_t)nbp->bf_insns,
			    (caddr_t)newcode, newcodelen)) != 0) {
				free(newcode, M_DEVBUF, 0);
				return error;
			}
			if (!bpf_validate(newcode, nbp->bf_len)) {
				free(newcode, M_DEVBUF, 0);
				return EINVAL;
			}
		} else
			newcode = 0;
		bp = (cmd == PPPIOCSPASS) ?
		    &sc->sc_pass_filt : &sc->sc_active_filt;
		oldcode = bp->bf_insns;
		s = splnet();
		bp->bf_len = nbp->bf_len;
		bp->bf_insns = newcode;
		splx(s);
		if (oldcode != 0)
			free(oldcode, M_DEVBUF, 0);
		break;
#endif

	default:
		return (-1);
	}
	return (0);
}

/*
 * Process an ioctl request to the ppp network interface.
 */
static int
pppsioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
{
	struct ppp_softc *sc = ifp->if_softc;
	struct ifaddr *ifa = (struct ifaddr *)data;
	struct ifreq *ifr = (struct ifreq *)data;
	struct ppp_stats *psp;
#ifdef	PPP_COMPRESS
	struct ppp_comp_stats *pcp;
#endif
	int s = splnet(), error = 0;

	switch (cmd) {
	case SIOCSIFFLAGS:
		if ((ifp->if_flags & IFF_RUNNING) == 0)
			ifp->if_flags &= ~IFF_UP;
		break;

	case SIOCSIFADDR:
		if (ifa->ifa_addr->sa_family != AF_INET)
			error = EAFNOSUPPORT;
		break;

	case SIOCSIFDSTADDR:
		if (ifa->ifa_addr->sa_family != AF_INET)
			error = EAFNOSUPPORT;
		break;

	case SIOCSIFMTU:
		sc->sc_if.if_mtu = ifr->ifr_mtu;
		break;

	case SIOCADDMULTI:
	case SIOCDELMULTI:
		break;

	case SIOCGPPPSTATS:
		psp = &((struct ifpppstatsreq *) data)->stats;
		bzero(psp, sizeof(*psp));
		psp->p = sc->sc_stats;
#if defined(VJC) && !defined(SL_NO_STATS)
		if (sc->sc_comp) {
			psp->vj.vjs_packets = sc->sc_comp->sls_packets;
			psp->vj.vjs_compressed = sc->sc_comp->sls_compressed;
			psp->vj.vjs_searches = sc->sc_comp->sls_searches;
			psp->vj.vjs_misses = sc->sc_comp->sls_misses;
			psp->vj.vjs_uncompressedin =
			    sc->sc_comp->sls_uncompressedin;
			psp->vj.vjs_compressedin =
			    sc->sc_comp->sls_compressedin;
			psp->vj.vjs_errorin = sc->sc_comp->sls_errorin;
			psp->vj.vjs_tossed = sc->sc_comp->sls_tossed;
		}
#endif /* VJC */
		break;

#ifdef PPP_COMPRESS
	case SIOCGPPPCSTATS:
		pcp = &((struct ifpppcstatsreq *) data)->stats;
		bzero(pcp, sizeof(*pcp));
		if (sc->sc_xc_state != NULL)
			(*sc->sc_xcomp->comp_stat)(sc->sc_xc_state, &pcp->c);
		if (sc->sc_rc_state != NULL)
			(*sc->sc_rcomp->decomp_stat)(sc->sc_rc_state, &pcp->d);
		break;
#endif /* PPP_COMPRESS */

	default:
		error = ENOTTY;
	}
	splx(s);
	return (error);
}

/*
 * Queue a packet.  Start transmission if not active.
 * Packet is placed in Information field of PPP frame.
 */
int
pppoutput(struct ifnet *ifp, struct mbuf *m0, struct sockaddr *dst,
    struct rtentry *rtp)
{
	struct ppp_softc *sc = ifp->if_softc;
	int protocol, address, control;
	u_char *cp;
	int error;
	enum NPmode mode;
	int len;

	if (sc->sc_devp == NULL || (ifp->if_flags & IFF_RUNNING) == 0
	    || ((ifp->if_flags & IFF_UP) == 0 && dst->sa_family != AF_UNSPEC)) {
		error = ENETDOWN;	/* sort of */
		goto bad;
	}

#ifdef DIAGNOSTIC
	if (ifp->if_rdomain != rtable_l2(m0->m_pkthdr.ph_rtableid)) {
		printf("%s: trying to send packet on wrong domain. "
		    "if %d vs. mbuf %d, AF %d\n", ifp->if_xname,
		    ifp->if_rdomain, rtable_l2(m0->m_pkthdr.ph_rtableid),
		    dst->sa_family);
	}
#endif

	/*
	 * Compute PPP header.
	 */
	switch (dst->sa_family) {
	case AF_INET:
		address = PPP_ALLSTATIONS;
		control = PPP_UI;
		protocol = PPP_IP;
		mode = sc->sc_npmode[NP_IP];
		break;
	case AF_UNSPEC:
		address = PPP_ADDRESS(dst->sa_data);
		control = PPP_CONTROL(dst->sa_data);
		protocol = PPP_PROTOCOL(dst->sa_data);
		mode = NPMODE_PASS;
		break;
	default:
		printf("%s: af%d not supported\n", ifp->if_xname,
		    dst->sa_family);
		error = EAFNOSUPPORT;
		goto bad;
	}

	/*
	 * Drop this packet, or return an error, if necessary.
	 */
	if (mode == NPMODE_ERROR) {
		error = ENETDOWN;
		goto bad;
	}
	if (mode == NPMODE_DROP) {
		error = 0;
		goto bad;
	}

	/*
	 * Add PPP header.  If no space in first mbuf, allocate another.
	 */
	M_PREPEND(m0, PPP_HDRLEN, M_DONTWAIT);
	if (m0 == NULL) {
		error = ENOBUFS;
		goto bad;
	}

	cp = mtod(m0, u_char *);
	*cp++ = address;
	*cp++ = control;
	*cp++ = protocol >> 8;
	*cp++ = protocol & 0xff;

	if ((m0->m_flags & M_PKTHDR) == 0)
		panic("mbuf packet without packet header!");
	len = m0->m_pkthdr.len;

	if (sc->sc_flags & SC_LOG_OUTPKT) {
		printf("%s output: ", ifp->if_xname);
		pppdumpm(m0);
	}

	if ((protocol & 0x8000) == 0) {
#if NBPFILTER > 0
		/*
		 * Apply the pass and active filters to the packet,
		 * but only if it is a data packet.
		 */
		*mtod(m0, u_char *) = 1;	/* indicates outbound */
		if (sc->sc_pass_filt.bf_insns != 0 &&
		    bpf_filter(sc->sc_pass_filt.bf_insns, (u_char *)m0,
		    len, 0) == 0) {
			error = 0; /* drop this packet */
			goto bad;
		}

		/*
		 * Update the time we sent the most recent packet.
		 */
		if (sc->sc_active_filt.bf_insns == 0 ||
		    bpf_filter(sc->sc_active_filt.bf_insns, (u_char *)m0,
		    len, 0))
			sc->sc_last_sent = getuptime();

		*mtod(m0, u_char *) = address;
#else
		/*
		 * Update the time we sent the most recent packet.
		 */
		sc->sc_last_sent = getuptime();
#endif
	}

#if NBPFILTER > 0
	/* See if bpf wants to look at the packet. */
	if (ifp->if_bpf)
		bpf_mtap(ifp->if_bpf, m0, BPF_DIRECTION_OUT);
#endif

	/*
	 * Put the packet on the appropriate queue.
	 */
	if (mode == NPMODE_QUEUE) {
		/* XXX we should limit the number of packets on this queue */
		ml_enqueue(&sc->sc_npqueue, m0);
	} else {
		error = ifq_enqueue(&sc->sc_if.if_snd, m0);
		if (error) {
			sc->sc_if.if_oerrors++;
			sc->sc_stats.ppp_oerrors++;
			return (error);
		}
		(*sc->sc_start)(sc);
	}
	ifp->if_opackets++;
	ifp->if_obytes += len;

	return (0);

bad:
	m_freem(m0);
	return (error);
}



/*
 * After a change in the NPmode for some NP, move packets from the
 * npqueue to the send queue or the fast queue as appropriate.
 */
static void
ppp_requeue(struct ppp_softc *sc)
{
	struct mbuf_list ml = MBUF_LIST_INITIALIZER();
	struct mbuf *m;
	enum NPmode mode;
	int error;

	while ((m = ml_dequeue(&sc->sc_npqueue)) != NULL) {
		switch (PPP_PROTOCOL(mtod(m, u_char *))) {
		case PPP_IP:
			mode = sc->sc_npmode[NP_IP];
			break;
		default:
			mode = NPMODE_PASS;
		}

		switch (mode) {
		case NPMODE_PASS:
			error = ifq_enqueue(&sc->sc_if.if_snd, m);
			if (error) {
				sc->sc_if.if_oerrors++;
				sc->sc_stats.ppp_oerrors++;
			}
			break;

		case NPMODE_DROP:
		case NPMODE_ERROR:
			m_freem(m);
			break;

		case NPMODE_QUEUE:
			ml_enqueue(&ml, m);
			break;
		}
	}
	sc->sc_npqueue = ml;
}

/*
 * Transmitter has finished outputting some stuff;
 */
void
ppp_restart(struct ppp_softc *sc)
{
	int s = splnet();

	sc->sc_flags &= ~SC_TBUSY;
	schednetisr(NETISR_PPP);
	splx(s);
}

/*
 * Get a packet to send.
 */
struct mbuf *
ppp_dequeue(struct ppp_softc *sc)
{
	struct mbuf *m, *mp;
	u_char *cp;
	int address, control, protocol;

	/*
	 * Grab a packet to send: first try the fast queue, then the
	 * normal queue.
	 */
	m = ifq_dequeue(&sc->sc_if.if_snd);
	if (m == NULL)
		return NULL;

	++sc->sc_stats.ppp_opackets;

	/*
	 * Extract the ppp header of the new packet.
	 * The ppp header will be in one mbuf.
	 */
	cp = mtod(m, u_char *);
	address = PPP_ADDRESS(cp);
	control = PPP_CONTROL(cp);
	protocol = PPP_PROTOCOL(cp);

	switch (protocol) {
	case PPP_IP:
#ifdef VJC
		/*
		 * If the packet is a TCP/IP packet, see if we can compress it.
		 */
		if ((sc->sc_flags & SC_COMP_TCP) && sc->sc_comp != NULL) {
			struct ip *ip;
			int type;

			mp = m;
			ip = (struct ip *)(cp + PPP_HDRLEN);
			if (mp->m_len <= PPP_HDRLEN) {
				mp = mp->m_next;
				if (mp == NULL)
					break;
				ip = mtod(mp, struct ip *);
			}
			/*
			 * this code assumes the IP/TCP header is in one
			 * non-shared mbuf.
			 */
			if (ip->ip_p == IPPROTO_TCP) {
				type = sl_compress_tcp(mp, ip, sc->sc_comp,
				    !(sc->sc_flags & SC_NO_TCP_CCID));
				switch (type) {
				case TYPE_UNCOMPRESSED_TCP:
					protocol = PPP_VJC_UNCOMP;
					break;
				case TYPE_COMPRESSED_TCP:
					protocol = PPP_VJC_COMP;
					cp = mtod(m, u_char *);
					cp[0] = address; /* header has moved */
					cp[1] = control;
					cp[2] = 0;
					break;
				}
				/* update protocol in PPP header */
				cp[3] = protocol;
			}
		}
#endif	/* VJC */
		break;

#ifdef PPP_COMPRESS
	case PPP_CCP:
		ppp_ccp(sc, m, 0);
		break;
#endif	/* PPP_COMPRESS */
	}

#ifdef PPP_COMPRESS
	if (protocol != PPP_LCP && protocol != PPP_CCP &&
	    sc->sc_xc_state && (sc->sc_flags & SC_COMP_RUN)) {
		struct mbuf *mcomp = NULL;
		int slen;

		slen = 0;
		for (mp = m; mp != NULL; mp = mp->m_next)
			slen += mp->m_len;
		(*sc->sc_xcomp->compress)(sc->sc_xc_state, &mcomp, m, slen,
		    (sc->sc_flags & SC_CCP_UP ?
		    sc->sc_if.if_mtu + PPP_HDRLEN : 0));
		if (mcomp != NULL) {
			if (sc->sc_flags & SC_CCP_UP) {
				/* Send the compressed packet instead. */
				m_freem(m);
				m = mcomp;
				cp = mtod(m, u_char *);
				protocol = cp[3];
			} else {
				/*
				 * Can't transmit compressed packets until
				 * CCP is up.
				 */
				m_freem(mcomp);
			}
		}
	}
#endif	/* PPP_COMPRESS */

	/*
	 * Compress the address/control and protocol, if possible.
	 */
	if (sc->sc_flags & SC_COMP_AC && address == PPP_ALLSTATIONS &&
	    control == PPP_UI && protocol != PPP_ALLSTATIONS &&
	    protocol != PPP_LCP) {
		/* can compress address/control */
		m->m_data += 2;
		m->m_len -= 2;
	}
	if (sc->sc_flags & SC_COMP_PROT && protocol < 0xFF) {
		/* can compress protocol */
		if (mtod(m, u_char *) == cp) {
			cp[2] = cp[1];	/* move address/control up */
			cp[1] = cp[0];
		}
		++m->m_data;
		--m->m_len;
	}

	return m;
}

/*
 * Software interrupt routine.
 */
void
pppintr(void)
{
	struct ppp_softc *sc;
	int s;
	struct ppp_pkt *pkt;
	struct mbuf *m;

	NET_ASSERT_LOCKED();

	LIST_FOREACH(sc, &ppp_softc_list, sc_list) {
		if (!(sc->sc_flags & SC_TBUSY) &&
		    (!ifq_empty(&sc->sc_if.if_snd))) {
			s = splnet();
			sc->sc_flags |= SC_TBUSY;
			splx(s);
			(*sc->sc_start)(sc);
		}
		while ((pkt = ppp_pkt_dequeue(&sc->sc_rawq)) != NULL) {
			m = ppp_pkt_mbuf(pkt);
			if (m == NULL)
				continue;
			ppp_inproc(sc, m);
		}
	}
}

#ifdef PPP_COMPRESS
/*
 * Handle a CCP packet.  `rcvd' is 1 if the packet was received,
 * 0 if it is about to be transmitted.
 */
static void
ppp_ccp(struct ppp_softc *sc, struct mbuf *m, int rcvd)
{
	u_char *dp, *ep;
	struct mbuf *mp;
	int slen, s;

	/*
	 * Get a pointer to the data after the PPP header.
	 */
	if (m->m_len <= PPP_HDRLEN) {
		mp = m->m_next;
		if (mp == NULL)
			return;
		dp = mtod(mp, u_char *);
	} else {
		mp = m;
		dp = mtod(mp, u_char *) + PPP_HDRLEN;
	}

	ep = mtod(mp, u_char *) + mp->m_len;
	if (dp + CCP_HDRLEN > ep)
		return;
	slen = CCP_LENGTH(dp);
	if (dp + slen > ep) {
		if (sc->sc_flags & SC_DEBUG) {
			printf("if_ppp/ccp: not enough data in mbuf"
			    " (%p+%x > %p+%x)\n", dp, slen,
			    mtod(mp, u_char *), mp->m_len);
		}
		return;
	}

	switch (CCP_CODE(dp)) {
	case CCP_CONFREQ:
	case CCP_TERMREQ:
	case CCP_TERMACK:
		/* CCP must be going down - disable compression */
		if (sc->sc_flags & SC_CCP_UP) {
			s = splnet();
			sc->sc_flags &=
			    ~(SC_CCP_UP | SC_COMP_RUN | SC_DECOMP_RUN);
			splx(s);
		}
		break;

	case CCP_CONFACK:
		if (sc->sc_flags & SC_CCP_OPEN &&
		    !(sc->sc_flags & SC_CCP_UP) &&
		    slen >= CCP_HDRLEN + CCP_OPT_MINLEN &&
		    slen >= CCP_OPT_LENGTH(dp + CCP_HDRLEN) + CCP_HDRLEN) {
			if (!rcvd) {
				/* we're agreeing to send compressed packets. */
				if (sc->sc_xc_state != NULL &&
				    (*sc->sc_xcomp->comp_init)(sc->sc_xc_state,
				    dp + CCP_HDRLEN, slen - CCP_HDRLEN,
				    sc->sc_unit, 0, sc->sc_flags & SC_DEBUG)) {
					s = splnet();
					sc->sc_flags |= SC_COMP_RUN;
					splx(s);
				}
			} else {
				/* peer agrees to send compressed packets */
				if (sc->sc_rc_state != NULL &&
				    (*sc->sc_rcomp->decomp_init)(
				     sc->sc_rc_state, dp + CCP_HDRLEN,
				     slen - CCP_HDRLEN, sc->sc_unit, 0,
				     sc->sc_mru, sc->sc_flags & SC_DEBUG)) {
					s = splnet();
					sc->sc_flags |= SC_DECOMP_RUN;
					sc->sc_flags &=
					    ~(SC_DC_ERROR | SC_DC_FERROR);
					splx(s);
				}
			}
		}
		break;

	case CCP_RESETACK:
		if (sc->sc_flags & SC_CCP_UP) {
			if (!rcvd) {
				if (sc->sc_xc_state &&
				    (sc->sc_flags & SC_COMP_RUN)) {
					(*sc->sc_xcomp->comp_reset)(
					    sc->sc_xc_state);
				}
			} else {
				if (sc->sc_rc_state &&
				    (sc->sc_flags & SC_DECOMP_RUN)) {
					(*sc->sc_rcomp->decomp_reset)(
					    sc->sc_rc_state);
					s = splnet();
					sc->sc_flags &= ~SC_DC_ERROR;
					splx(s);
				}
			}
		}
		break;
	}
}

/*
 * CCP is down; free (de)compressor state if necessary.
 */
static void
ppp_ccp_closed(struct ppp_softc *sc)
{
	if (sc->sc_xc_state) {
		(*sc->sc_xcomp->comp_free)(sc->sc_xc_state);
		sc->sc_xc_state = NULL;
	}
	if (sc->sc_rc_state) {
		(*sc->sc_rcomp->decomp_free)(sc->sc_rc_state);
		sc->sc_rc_state = NULL;
	}
}
#endif /* PPP_COMPRESS */

/*
 * PPP packet input routine.
 * The caller has checked and removed the FCS and has inserted
 * the address/control bytes and the protocol high byte if they
 * were omitted.
 */
void
ppppktin(struct ppp_softc *sc, struct ppp_pkt *pkt, int lost)
{
	pkt->p_hdr.ph_errmark = lost;
	if (ppp_pkt_enqueue(&sc->sc_rawq, pkt) == 0)
		schednetisr(NETISR_PPP);
}

/*
 * Process a received PPP packet, doing decompression as necessary.
 */
#define COMPTYPE(proto)	((proto) == PPP_VJC_COMP? TYPE_COMPRESSED_TCP: \
			 TYPE_UNCOMPRESSED_TCP)

static void
ppp_inproc(struct ppp_softc *sc, struct mbuf *m)
{
	struct ifnet *ifp = &sc->sc_if;
	int s, ilen, xlen, proto, rv;
	u_char *cp, adrs, ctrl;
	struct mbuf *mp, *dmp = NULL;
	u_char *iphdr;
	u_int hlen;

	sc->sc_stats.ppp_ipackets++;

	if (sc->sc_flags & SC_LOG_INPKT) {
		ilen = 0;
		for (mp = m; mp != NULL; mp = mp->m_next)
			ilen += mp->m_len;
		printf("%s: got %d bytes\n", ifp->if_xname, ilen);
		pppdumpm(m);
	}

	cp = mtod(m, u_char *);
	adrs = PPP_ADDRESS(cp);
	ctrl = PPP_CONTROL(cp);
	proto = PPP_PROTOCOL(cp);

	if (m->m_flags & M_ERRMARK) {
		m->m_flags &= ~M_ERRMARK;
		s = splnet();
		sc->sc_flags |= SC_VJ_RESET;
		splx(s);
	}

#ifdef PPP_COMPRESS
	/*
	 * Decompress this packet if necessary, update the receiver's
	 * dictionary, or take appropriate action on a CCP packet.
	 */
	if (proto == PPP_COMP && sc->sc_rc_state &&
	    (sc->sc_flags & SC_DECOMP_RUN) && !(sc->sc_flags & SC_DC_ERROR) &&
	    !(sc->sc_flags & SC_DC_FERROR)) {
		/* decompress this packet */
		rv = (*sc->sc_rcomp->decompress)(sc->sc_rc_state, m, &dmp);
		if (rv == DECOMP_OK) {
			m_freem(m);
			if (dmp == NULL) {
				/*
				 * no error, but no decompressed packet
				 * produced
				 */
				return;
			}
			m = dmp;
			cp = mtod(m, u_char *);
			proto = PPP_PROTOCOL(cp);

		} else {
			/*
			 * An error has occurred in decompression.
			 * Pass the compressed packet up to pppd, which may
			 * take CCP down or issue a Reset-Req.
			 */
			if (sc->sc_flags & SC_DEBUG) {
				printf("%s: decompress failed %d\n",
				    ifp->if_xname, rv);
			}
			s = splnet();
			sc->sc_flags |= SC_VJ_RESET;
			if (rv == DECOMP_ERROR)
				sc->sc_flags |= SC_DC_ERROR;
			else
				sc->sc_flags |= SC_DC_FERROR;
			splx(s);
		}

	} else {
		if (sc->sc_rc_state && (sc->sc_flags & SC_DECOMP_RUN)) {
			(*sc->sc_rcomp->incomp)(sc->sc_rc_state, m);
		}
		if (proto == PPP_CCP) {
			ppp_ccp(sc, m, 1);
		}
	}
#endif

	ilen = 0;
	for (mp = m; mp != NULL; mp = mp->m_next)
		ilen += mp->m_len;

#ifdef VJC
	if (sc->sc_flags & SC_VJ_RESET) {
		/*
		* If we've missed a packet, we must toss subsequent compressed
		* packets which don't have an explicit connection ID.
		*/
		if (sc->sc_comp)
			sl_uncompress_tcp(NULL, 0, TYPE_ERROR, sc->sc_comp);
		s = splnet();
		sc->sc_flags &= ~SC_VJ_RESET;
		splx(s);
	}

	/*
	 * See if we have a VJ-compressed packet to uncompress.
	 */
	if (proto == PPP_VJC_COMP) {
		if ((sc->sc_flags & SC_REJ_COMP_TCP) || sc->sc_comp == 0)
			goto bad;

		xlen = sl_uncompress_tcp_core(cp + PPP_HDRLEN,
		    m->m_len - PPP_HDRLEN, ilen - PPP_HDRLEN,
		    TYPE_COMPRESSED_TCP, sc->sc_comp, &iphdr, &hlen);

		if (xlen <= 0) {
			if (sc->sc_flags & SC_DEBUG) {
				printf("%s: VJ uncompress failed "
				    "on type comp\n", ifp->if_xname);
			}
			goto bad;
		}

		/* Copy the PPP and IP headers into a new mbuf. */
		MGETHDR(mp, M_DONTWAIT, MT_DATA);
		if (mp == NULL)
			goto bad;
		mp->m_len = 0;
		mp->m_next = NULL;
		if (hlen + PPP_HDRLEN > MHLEN) {
			MCLGET(mp, M_DONTWAIT);
			if (m_trailingspace(mp) < hlen + PPP_HDRLEN) {
				m_freem(mp);
				/* lose if big headers and no clusters */
				goto bad;
			}
		}
		if (m->m_flags & M_PKTHDR)
			M_MOVE_HDR(mp, m);
		cp = mtod(mp, u_char *);
		cp[0] = adrs;
		cp[1] = ctrl;
		cp[2] = 0;
		cp[3] = PPP_IP;
		proto = PPP_IP;
		bcopy(iphdr, cp + PPP_HDRLEN, hlen);
		mp->m_len = hlen + PPP_HDRLEN;

		/*
		 * Trim the PPP and VJ headers off the old mbuf
		 * and stick the new and old mbufs together.
		 */
		m->m_data += PPP_HDRLEN + xlen;
		m->m_len -= PPP_HDRLEN + xlen;
		if (m->m_len <= m_trailingspace(mp)) {
			bcopy(mtod(m, u_char *),
			    mtod(mp, u_char *) + mp->m_len, m->m_len);
			mp->m_len += m->m_len;
			mp->m_next = m_free(m);
		} else
			mp->m_next = m;
		m = mp;
		ilen += hlen - xlen;

	} else if (proto == PPP_VJC_UNCOMP) {
		if ((sc->sc_flags & SC_REJ_COMP_TCP) || sc->sc_comp == 0)
			goto bad;

		xlen = sl_uncompress_tcp_core(cp + PPP_HDRLEN,
		    m->m_len - PPP_HDRLEN, ilen - PPP_HDRLEN,
		    TYPE_UNCOMPRESSED_TCP, sc->sc_comp, &iphdr, &hlen);

		if (xlen < 0) {
			if (sc->sc_flags & SC_DEBUG) {
				printf("%s: VJ uncompress failed "
				    "on type uncomp\n", ifp->if_xname);
			}
			goto bad;
		}

		proto = PPP_IP;
		cp[3] = PPP_IP;
	}
#endif /* VJC */

	m->m_pkthdr.len = ilen;
	m->m_pkthdr.ph_ifidx = ifp->if_index;

	/* mark incoming routing table */
	m->m_pkthdr.ph_rtableid = ifp->if_rdomain;

	if ((proto & 0x8000) == 0) {
#if NBPFILTER > 0
		/*
		 * See whether we want to pass this packet, and
		 * if it counts as link activity.
		 */
		adrs = *mtod(m, u_char *);	/* save address field */
		*mtod(m, u_char *) = 0;		/* indicate inbound */
		if (sc->sc_pass_filt.bf_insns != 0 &&
		    bpf_filter(sc->sc_pass_filt.bf_insns, (u_char *) m,
		     ilen, 0) == 0) {
			/* drop this packet */
			m_freem(m);
			return;
		}
		if (sc->sc_active_filt.bf_insns == 0 ||
		    bpf_filter(sc->sc_active_filt.bf_insns, (u_char *)m,
		     ilen, 0))
			sc->sc_last_recv = getuptime();

		*mtod(m, u_char *) = adrs;
#else
		/*
		 * Record the time that we received this packet.
		 */
		sc->sc_last_recv = getuptime();
#endif
	}

#if NBPFILTER > 0
	/* See if bpf wants to look at the packet. */
	if (ifp->if_bpf)
		bpf_mtap(ifp->if_bpf, m, BPF_DIRECTION_IN);
#endif

	rv = 0;
	switch (proto) {
	case PPP_IP:
		/*
		 * IP packet - take off the ppp header and pass it up to IP.
		 */
		if ((ifp->if_flags & IFF_UP) == 0 ||
		    sc->sc_npmode[NP_IP] != NPMODE_PASS) {
			/* interface is down - drop the packet. */
			m_freem(m);
			return;
		}
		m->m_pkthdr.len -= PPP_HDRLEN;
		m->m_data += PPP_HDRLEN;
		m->m_len -= PPP_HDRLEN;

		ipv4_input(ifp, m);
		rv = 1;
		break;

	default:
		/*
		 * Some other protocol - place on input queue for read().
		 */
		if (mq_enqueue(&sc->sc_inq, m) != 0) {
			if_congestion();
			rv = 0; /* failure */
		} else
			rv = 2; /* input queue */
		break;
	}

	if (rv == 0) {
		/* failure */
		if (sc->sc_flags & SC_DEBUG)
			printf("%s: input queue full\n", ifp->if_xname);
		ifp->if_iqdrops++;
		goto dropped;
	}

	ifp->if_ipackets++;
	ifp->if_ibytes += ilen;

	if (rv == 2)
		(*sc->sc_ctlp)(sc);

	return;

bad:
	m_freem(m);
dropped:
	sc->sc_if.if_ierrors++;
	sc->sc_stats.ppp_ierrors++;
}

#define MAX_DUMP_BYTES	128

static void
pppdumpm(struct mbuf *m0)
{
	char buf[3*MAX_DUMP_BYTES+4];
	char *bp = buf;
	struct mbuf *m;
	static char digits[] = "0123456789abcdef";

	for (m = m0; m; m = m->m_next) {
		int l = m->m_len;
		u_char *rptr = mtod(m, u_char *);

		while (l--) {
			if (bp > buf + sizeof(buf) - 4)
				goto done;

			/* convert byte to ascii hex */
			*bp++ = digits[*rptr >> 4];
			*bp++ = digits[*rptr++ & 0xf];
		}

		if (m->m_next) {
			if (bp > buf + sizeof(buf) - 3)
				goto done;
			*bp++ = '|';
		} else
			*bp++ = ' ';
	}
done:
	if (m)
		*bp++ = '>';
	*bp = 0;
	printf("%s\n", buf);
}

static void
ppp_ifstart(struct ifnet *ifp)
{
	struct ppp_softc *sc;

	sc = ifp->if_softc;
	(*sc->sc_start)(sc);
}

void
ppp_pkt_list_init(struct ppp_pkt_list *pl, u_int limit)
{
	mtx_init(&pl->pl_mtx, IPL_TTY);
	pl->pl_head = pl->pl_tail = NULL;
	pl->pl_count = 0;
	pl->pl_limit = limit;
}

int
ppp_pkt_enqueue(struct ppp_pkt_list *pl, struct ppp_pkt *pkt)
{
	int drop = 0;

	mtx_enter(&pl->pl_mtx);
	if (pl->pl_count < pl->pl_limit) {
		if (pl->pl_tail == NULL)
			pl->pl_head = pl->pl_tail = pkt;
		else {
			PKT_NEXTPKT(pl->pl_tail) = pkt;
			pl->pl_tail = pkt;
		}
		PKT_NEXTPKT(pkt) = NULL;
		pl->pl_count++;
	} else
		drop = 1;
	mtx_leave(&pl->pl_mtx);

	if (drop)
		ppp_pkt_free(pkt);

	return (drop);
}

struct ppp_pkt *
ppp_pkt_dequeue(struct ppp_pkt_list *pl)
{
	struct ppp_pkt *pkt;

	mtx_enter(&pl->pl_mtx);
	pkt = pl->pl_head;
	if (pkt != NULL) {
		pl->pl_head = PKT_NEXTPKT(pkt);
		if (pl->pl_head == NULL)
			pl->pl_tail = NULL;

		pl->pl_count--;
	}
	mtx_leave(&pl->pl_mtx);

	return (pkt);
}

struct mbuf *
ppp_pkt_mbuf(struct ppp_pkt *pkt0)
{
	extern struct pool ppp_pkts;
	struct mbuf *m0 = NULL, **mp = &m0, *m;
	struct ppp_pkt *pkt = pkt0;
	size_t len = 0;

	do {
		MGETHDR(m, M_DONTWAIT, MT_DATA);
		if (m == NULL)
			goto fail;

		MEXTADD(m, pkt, sizeof(*pkt), M_EXTWR,
		    MEXTFREE_POOL, &ppp_pkts);
		m->m_data += sizeof(pkt->p_hdr);
		m->m_len = PKT_LEN(pkt);

		len += m->m_len;

		*mp = m;
		mp = &m->m_next;

		pkt = PKT_NEXT(pkt);
	} while (pkt != NULL);

	m0->m_pkthdr.len = len;
	if (pkt0->p_hdr.ph_errmark)
		m0->m_flags |= M_ERRMARK;

	return (m0);

fail:
	m_freem(m0);
	ppp_pkt_free(pkt0);
	return (NULL);
}

#endif	/* NPPP > 0 */
IABSD.fr/src/sys/net/if_ppp.c

Commit

IABSD.fr/src /sys/net/if_ppp.c
