ppp.c

经典的ppp程序

	    DPRINT1("ppp%d: lower stream still connected on close?\n",
		    up->mn);
	    LOCK_LOWER_W;
	    up->lowerq->q_ptr = 0;
	    RD(up->lowerq)->q_ptr = 0;
	    up->lowerq = 0;
	    UNLOCK_LOWER;
	}

	/*
	 * This stream represents a PPA:
	 * For all streams attached to the PPA, clear their
	 * references to this PPA.
	 * Then remove this PPA from the list of PPAs.
	 */
	for (as = up->next; as != 0; as = asnext) {
	    asnext = as->next;
	    as->next = 0;
	    as->ppa = 0;
	    if (as->flags & US_BLOCKED) {
		as->flags &= ~US_BLOCKED;
		flushq(WR(as->q), FLUSHDATA);
	    }
	}
	for (upp = &ppas; *upp != 0; upp = &(*upp)->nextppa)
	    if (*upp == up) {
		*upp = up->nextppa;
		break;
	    }
#ifdef LACHTCP
	/* Remove the statistics from the active list.  */
	for (ifp = ifstats, pifp = 0; ifp; ifp = ifp->ifs_next) {
	    if (ifp == &up->ifstats) {
		if (pifp)
		    pifp->ifs_next = ifp->ifs_next;
		else
		    ifstats = ifp->ifs_next;
		break;
	    }
	    pifp = ifp;
	}
#endif
    } else {
	/*
	 * If this stream is attached to a PPA,
	 * remove it from the PPA's list.
	 */
	if ((as = up->ppa) != 0) {
	    for (; as->next != 0; as = as->next)
		if (as->next == up) {
		    as->next = up->next;
		    break;
		}
	}
    }

#ifdef SOL2
    if (up->kstats)
	kstat_delete(up->kstats);
    mutex_destroy(&up->stats_lock);
#endif

    q->q_ptr = NULL;
    WR(q)->q_ptr = NULL;

    for (prevp = &minor_devs; *prevp != 0; prevp = &(*prevp)->nextmn) {
	if (*prevp == up) {
	    *prevp = up->nextmn;
	    break;
	}
    }
    FREE(up, sizeof(upperstr_t));
    --ppp_count;

    return 0;
}

/*
 * A message from on high.  We do one of three things:
 *	- qreply()
 *	- put the message on the lower write stream
 *	- queue it for our service routine
 */
static int
pppuwput(q, mp)
    queue_t *q;
    mblk_t *mp;
{
    upperstr_t *us, *ppa, *nps;
    struct iocblk *iop;
    struct linkblk *lb;
#ifdef LACHTCP
    struct ifreq *ifr;
    int i;
#endif
    queue_t *lq;
    int error, n, sap;
    mblk_t *mq;
    struct ppp_idle *pip;
#ifdef PRIOQ
    queue_t *tlq;
#endif	/* PRIOQ */
#ifdef NO_DLPI
    upperstr_t *os;
#endif

    us = (upperstr_t *) q->q_ptr;
    if (us == 0) {
	DPRINT("pppuwput: q_ptr = 0!\n");
	return 0;
    }
    if (mp == 0) {
	DPRINT1("pppuwput/%d: mp = 0!\n", us->mn);
	return 0;
    }
    if (mp->b_datap == 0) {
	DPRINT1("pppuwput/%d: mp->b_datap = 0!\n", us->mn);
	return 0;
    }
    switch (mp->b_datap->db_type) {
#ifndef NO_DLPI
    case M_PCPROTO:
    case M_PROTO:
	dlpi_request(q, mp, us);
	break;
#endif /* NO_DLPI */

    case M_DATA:
	if (us->flags & US_DBGLOG)
	    DPRINT3("ppp/%d: uwput M_DATA len=%d flags=%x\n",
		    us->mn, msgdsize(mp), us->flags);
	if (us->ppa == 0 || msgdsize(mp) > us->ppa->mtu + PPP_HDRLEN
#ifndef NO_DLPI
	    || (us->flags & US_CONTROL) == 0
#endif /* NO_DLPI */
	    ) {
	    DPRINT1("pppuwput: junk data len=%d\n", msgdsize(mp));
	    freemsg(mp);
	    break;
	}
#ifdef NO_DLPI
	if ((us->flags & US_CONTROL) == 0 && !pass_packet(us, mp, 1))
	    break;
#endif
	if (!send_data(mp, us))
	    putq(q, mp);
	break;

    case M_IOCTL:
	iop = (struct iocblk *) mp->b_rptr;
	error = EINVAL;
	if (us->flags & US_DBGLOG)
	    DPRINT3("ppp/%d: ioctl %x count=%d\n",
		    us->mn, iop->ioc_cmd, iop->ioc_count);
	switch (iop->ioc_cmd) {
#if defined(SOL2)
	case DLIOCRAW:	    /* raw M_DATA mode */
	    us->flags |= US_RAWDATA;
	    error = 0;
	    break;
#endif /* defined(SOL2) */
	case I_LINK:
	    if ((us->flags & US_CONTROL) == 0 || us->lowerq != 0)
		break;
	    if (mp->b_cont == 0) {
		DPRINT1("pppuwput/%d: ioctl I_LINK b_cont = 0!\n", us->mn);
		break;
	    }
	    lb = (struct linkblk *) mp->b_cont->b_rptr;
	    lq = lb->l_qbot;
	    if (lq == 0) {
		DPRINT1("pppuwput/%d: ioctl I_LINK l_qbot = 0!\n", us->mn);
		break;
	    }
	    LOCK_LOWER_W;
	    us->lowerq = lq;
	    lq->q_ptr = (caddr_t) q;
	    RD(lq)->q_ptr = (caddr_t) us->q;
	    UNLOCK_LOWER;
	    iop->ioc_count = 0;
	    error = 0;
	    us->flags &= ~US_LASTMOD;
	    /* Unblock upper streams which now feed this lower stream. */
	    qenable(q);
	    /* Send useful information down to the modules which
	       are now linked below us. */
	    putctl2(lq, M_CTL, PPPCTL_UNIT, us->ppa_id);
	    putctl4(lq, M_CTL, PPPCTL_MRU, us->mru);
	    putctl4(lq, M_CTL, PPPCTL_MTU, us->mtu);
#ifdef PRIOQ
            /* Lower tty driver's queue hiwat/lowat from default 4096/128
               to 256/128 since we don't want queueing of data on
               output to physical device */

            freezestr(lq);
            for (tlq = lq; tlq->q_next != NULL; tlq = tlq->q_next)
		;
            strqset(tlq, QHIWAT, 0, 256);
            strqset(tlq, QLOWAT, 0, 128);
            unfreezestr(lq);
#endif	/* PRIOQ */
	    break;

	case I_UNLINK:
	    if (mp->b_cont == 0) {
		DPRINT1("pppuwput/%d: ioctl I_UNLINK b_cont = 0!\n", us->mn);
		break;
	    }
	    lb = (struct linkblk *) mp->b_cont->b_rptr;
#if DEBUG
	    if (us->lowerq != lb->l_qbot) {
		DPRINT2("ppp unlink: lowerq=%x qbot=%x\n",
			us->lowerq, lb->l_qbot);
		break;
	    }
#endif
	    iop->ioc_count = 0;
	    qwriter(q, mp, detach_lower, PERIM_OUTER);
	    error = -1;
	    break;

	case PPPIO_NEWPPA:
	    if (us->flags & US_CONTROL)
		break;
	    if ((us->flags & US_PRIV) == 0) {
		error = EPERM;
		break;
	    }
	    /* Arrange to return an int */
	    if ((mq = mp->b_cont) == 0
		|| mq->b_datap->db_lim - mq->b_rptr < sizeof(int)) {
		mq = allocb(sizeof(int), BPRI_HI);
		if (mq == 0) {
		    error = ENOSR;
		    break;
		}
		if (mp->b_cont != 0)
		    freemsg(mp->b_cont);
		mp->b_cont = mq;
		mq->b_cont = 0;
	    }
	    iop->ioc_count = sizeof(int);
	    mq->b_wptr = mq->b_rptr + sizeof(int);
	    qwriter(q, mp, new_ppa, PERIM_OUTER);
	    error = -1;
	    break;

	case PPPIO_ATTACH:
	    /* like dlpi_attach, for programs which can't write to
	       the stream (like pppstats) */
	    if (iop->ioc_count != sizeof(int) || us->ppa != 0)
		break;
	    if (mp->b_cont == 0) {
		DPRINT1("pppuwput/%d: ioctl PPPIO_ATTACH b_cont = 0!\n", us->mn);
		break;
	    }
	    n = *(int *)mp->b_cont->b_rptr;
	    for (ppa = ppas; ppa != 0; ppa = ppa->nextppa)
		if (ppa->ppa_id == n)
		    break;
	    if (ppa == 0)
		break;
	    us->ppa = ppa;
	    iop->ioc_count = 0;
	    qwriter(q, mp, attach_ppa, PERIM_OUTER);
	    error = -1;
	    break;

#ifdef NO_DLPI
	case PPPIO_BIND:
	    /* Attach to a given SAP. */
	    if (iop->ioc_count != sizeof(int) || us->ppa == 0)
		break;
	    if (mp->b_cont == 0) {
		DPRINT1("pppuwput/%d: ioctl PPPIO_BIND b_cont = 0!\n", us->mn);
		break;
	    }
	    n = *(int *)mp->b_cont->b_rptr;
	    /* n must be a valid PPP network protocol number. */
	    if (n < 0x21 || n > 0x3fff || (n & 0x101) != 1)
		break;
	    /* check that no other stream is bound to this sap already. */
	    for (os = us->ppa; os != 0; os = os->next)
		if (os->sap == n)
		    break;
	    if (os != 0)
		break;
	    us->sap = n;
	    iop->ioc_count = 0;
	    error = 0;
	    break;
#endif /* NO_DLPI */

	case PPPIO_MRU:
	    if (iop->ioc_count != sizeof(int) || (us->flags & US_CONTROL) == 0)
		break;
	    if (mp->b_cont == 0) {
		DPRINT1("pppuwput/%d: ioctl PPPIO_MRU b_cont = 0!\n", us->mn);
		break;
	    }
	    n = *(int *)mp->b_cont->b_rptr;
	    if (n <= 0 || n > PPP_MAXMRU)
		break;
	    if (n < PPP_MRU)
		n = PPP_MRU;
	    us->mru = n;
	    if (us->lowerq)
		putctl4(us->lowerq, M_CTL, PPPCTL_MRU, n);
	    error = 0;
	    iop->ioc_count = 0;
	    break;

	case PPPIO_MTU:
	    if (iop->ioc_count != sizeof(int) || (us->flags & US_CONTROL) == 0)
		break;
	    if (mp->b_cont == 0) {
		DPRINT1("pppuwput/%d: ioctl PPPIO_MTU b_cont = 0!\n", us->mn);
		break;
	    }
	    n = *(int *)mp->b_cont->b_rptr;
	    if (n <= 0 || n > PPP_MAXMTU)
		break;
	    us->mtu = n;
#ifdef LACHTCP
	    /* The MTU reported in netstat, not used as IP max packet size! */
	    us->ifstats.ifs_mtu = n;
#endif
	    if (us->lowerq)
		putctl4(us->lowerq, M_CTL, PPPCTL_MTU, n);
	    error = 0;
	    iop->ioc_count = 0;
	    break;

	case PPPIO_LASTMOD:
	    us->flags |= US_LASTMOD;
	    error = 0;
	    break;

	case PPPIO_DEBUG:
	    if (iop->ioc_count != sizeof(int))
		break;
	    if (mp->b_cont == 0) {
		DPRINT1("pppuwput/%d: ioctl PPPIO_DEBUG b_cont = 0!\n", us->mn);
		break;
	    }
	    n = *(int *)mp->b_cont->b_rptr;
	    if (n == PPPDBG_DUMP + PPPDBG_DRIVER) {
		qwriter(q, NULL, debug_dump, PERIM_OUTER);
		iop->ioc_count = 0;
		error = -1;
	    } else if (n == PPPDBG_LOG + PPPDBG_DRIVER) {
		DPRINT1("ppp/%d: debug log enabled\n", us->mn);
		us->flags |= US_DBGLOG;
		iop->ioc_count = 0;
		error = 0;
	    } else {
		if (us->ppa == 0 || us->ppa->lowerq == 0)
		    break;
		putnext(us->ppa->lowerq, mp);
		error = -1;
	    }
	    break;

	case PPPIO_NPMODE:
	    if (iop->ioc_count != 2 * sizeof(int))
		break;
	    if ((us->flags & US_CONTROL) == 0)
		break;
	    if (mp->b_cont == 0) {
		DPRINT1("pppuwput/%d: ioctl PPPIO_NPMODE b_cont = 0!\n", us->mn);
		break;
	    }
	    sap = ((int *)mp->b_cont->b_rptr)[0];
	    for (nps = us->next; nps != 0; nps = nps->next) {
		if (us->flags & US_DBGLOG)
		    DPRINT2("us = 0x%x, us->next->sap = 0x%x\n", nps, nps->sap);
		if (nps->sap == sap)
		    break;
	    }
	    if (nps == 0) {
		if (us->flags & US_DBGLOG)
		    DPRINT2("ppp/%d: no stream for sap %x\n", us->mn, sap);
		break;
	    }
	    /* XXX possibly should use qwriter here */
	    nps->npmode = (enum NPmode) ((int *)mp->b_cont->b_rptr)[1];
	    if (nps->npmode != NPMODE_QUEUE && (nps->flags & US_BLOCKED) != 0)
		qenable(WR(nps->q));
	    iop->ioc_count = 0;
	    error = 0;
	    break;

	case PPPIO_GIDLE:
	    if ((ppa = us->ppa) == 0)
		break;
	    mq = allocb(sizeof(struct ppp_idle), BPRI_HI);
	    if (mq == 0) {
		error = ENOSR;
		break;
	    }
	    if (mp->b_cont != 0)
		freemsg(mp->b_cont);
	    mp->b_cont = mq;
	    mq->b_cont = 0;
	    pip = (struct ppp_idle *) mq->b_wptr;
	    pip->xmit_idle = time - ppa->last_sent;
	    pip->recv_idle = time - ppa->last_recv;
	    mq->b_wptr += sizeof(struct ppp_idle);
	    iop->ioc_count = sizeof(struct ppp_idle);
	    error = 0;
	    break;

#ifdef LACHTCP
	case SIOCSIFNAME:
	    /* Sent from IP down to us.  Attach the ifstats structure.  */
	    if (iop->ioc_count != sizeof(struct ifreq) || us->ppa == 0)
	        break;
	    ifr = (struct ifreq *)mp->b_cont->b_rptr;
	    /* Find the unit number in the interface name.  */
	    for (i = 0; i < IFNAMSIZ; i++) {
		if (ifr->ifr_name[i] == 0 ||
		    (ifr->ifr_name[i] >= '0' &&
		     ifr->ifr_name[i] <= '9'))
		    break;
		else
		    us->ifname[i] = ifr->ifr_name[i];
	    }
	    us->ifname[i] = 0;

	    /* Convert the unit number to binary.  */
	    for (n = 0; i < IFNAMSIZ; i++) {
		if (ifr->ifr_name[i] == 0) {
		    break;
		}
	        else {
		    n = n * 10 + ifr->ifr_name[i] - '0';
		}
	    }

	    /* Verify the ppa.  */
	    if (us->ppa->ppa_id != n)
		break;
	    ppa = us->ppa;

	    /* Set up the netstat block.  */
	    strncpy (ppa->ifname, us->ifname, IFNAMSIZ);

	    ppa->ifstats.ifs_name = ppa->ifname;
	    ppa->ifstats.ifs_unit = n;
	    ppa->ifstats.ifs_active = us->state != DL_UNBOUND;
	    ppa->ifstats.ifs_mtu = ppa->mtu;

	    /* Link in statistics used by netstat.  */
	    ppa->ifstats.ifs_next = ifstats;
	    ifstats = &ppa->ifstats;

	    iop->ioc_count = 0;
	    error = 0;
	    break;

	case SIOCGIFFLAGS:
	    if (!(us->flags & US_CONTROL)) {
		if (us->ppa)
		    us = us->ppa;
	        else
		    break;
	    }
	    ((struct iocblk_in *)iop)->ioc_ifflags = us->ifflags;
	    error = 0;
	    break;

	case SIOCSIFFLAGS:
	    if (!(us->flags & US_CONTROL)) {
		if (us->ppa)
		    us = us->ppa;
		else
		    break;
	    }
	    us->ifflags = ((struct iocblk_in *)iop)->ioc_ifflags;
	    error = 0;
	    break;

	case SIOCSIFADDR:
	    if (!(us->flags & US_CONTROL)) {
		if (us->ppa)
		    us = us->ppa;
		else
		    break;
	    }
	    us->ifflags |= IFF_RUNNING;
	    ((struct iocblk_in *)iop)->ioc_ifflags |= IFF_RUNNING;
	    error = 0;
	    break;

	case SIOCSIFMTU:
	    /*
	     * Vanilla SVR4 systems don't handle SIOCSIFMTU, rather
	     * they take the MTU from the DL_INFO_ACK we sent in response