ppp.c

经典的ppp程序

	     * to their DL_INFO_REQ.  Fortunately, they will update the
	     * MTU if we send an unsolicited DL_INFO_ACK up.
	     */
	    if ((mq = allocb(sizeof(dl_info_req_t), BPRI_HI)) == 0)
		break;		/* should do bufcall */
	    ((union DL_primitives *)mq->b_rptr)->dl_primitive = DL_INFO_REQ;
	    mq->b_wptr = mq->b_rptr + sizeof(dl_info_req_t);
	    dlpi_request(q, mq, us);
	    error = 0;
	    break;

	case SIOCGIFNETMASK:
	case SIOCSIFNETMASK:
	case SIOCGIFADDR:
	case SIOCGIFDSTADDR:
	case SIOCSIFDSTADDR:
	case SIOCGIFMETRIC:
	    error = 0;
	    break;
#endif /* LACHTCP */

	default:
	    if (us->ppa == 0 || us->ppa->lowerq == 0)
		break;
	    us->ioc_id = iop->ioc_id;
	    error = -1;
	    switch (iop->ioc_cmd) {
	    case PPPIO_GETSTAT:
	    case PPPIO_GETCSTAT:
		if (us->flags & US_LASTMOD) {
		    error = EINVAL;
		    break;
		}
		putnext(us->ppa->lowerq, mp);
		break;
	    default:
		if (us->flags & US_PRIV)
		    putnext(us->ppa->lowerq, mp);
		else {
		    DPRINT1("ppp ioctl %x rejected\n", iop->ioc_cmd);
		    error = EPERM;
		}
		break;
	    }
	    break;
	}

	if (error > 0) {
	    iop->ioc_error = error;
	    mp->b_datap->db_type = M_IOCNAK;
	    qreply(q, mp);
	} else if (error == 0) {
	    mp->b_datap->db_type = M_IOCACK;
	    qreply(q, mp);
	}
	break;

    case M_FLUSH:
	if (us->flags & US_DBGLOG)
	    DPRINT2("ppp/%d: flush %x\n", us->mn, *mp->b_rptr);
	if (*mp->b_rptr & FLUSHW)
	    flushq(q, FLUSHDATA);
	if (*mp->b_rptr & FLUSHR) {
	    *mp->b_rptr &= ~FLUSHW;
	    qreply(q, mp);
	} else
	    freemsg(mp);
	break;

    default:
	freemsg(mp);
	break;
    }
    return 0;
}

#ifndef NO_DLPI
static void
dlpi_request(q, mp, us)
    queue_t *q;
    mblk_t *mp;
    upperstr_t *us;
{
    union DL_primitives *d = (union DL_primitives *) mp->b_rptr;
    int size = mp->b_wptr - mp->b_rptr;
    mblk_t *reply, *np;
    upperstr_t *ppa, *os;
    int sap, len;
    dl_info_ack_t *info;
    dl_bind_ack_t *ackp;
#if DL_CURRENT_VERSION >= 2
    dl_phys_addr_ack_t	*paddrack;
    static struct ether_addr eaddr = {0};
#endif

    if (us->flags & US_DBGLOG)
	DPRINT3("ppp/%d: dlpi prim %x len=%d\n", us->mn,
		d->dl_primitive, size);
    switch (d->dl_primitive) {
    case DL_INFO_REQ:
	if (size < sizeof(dl_info_req_t))
	    goto badprim;
	if ((reply = allocb(sizeof(dl_info_ack_t), BPRI_HI)) == 0)
	    break;		/* should do bufcall */
	reply->b_datap->db_type = M_PCPROTO;
	info = (dl_info_ack_t *) reply->b_wptr;
	reply->b_wptr += sizeof(dl_info_ack_t);
	bzero((caddr_t) info, sizeof(dl_info_ack_t));
	info->dl_primitive = DL_INFO_ACK;
	info->dl_max_sdu = us->ppa? us->ppa->mtu: PPP_MAXMTU;
	info->dl_min_sdu = 1;
	info->dl_addr_length = sizeof(uint);
	info->dl_mac_type = DL_ETHER;	/* a bigger lie */
	info->dl_current_state = us->state;
	info->dl_service_mode = DL_CLDLS;
	info->dl_provider_style = DL_STYLE2;
#if DL_CURRENT_VERSION >= 2
	info->dl_sap_length = sizeof(uint);
	info->dl_version = DL_CURRENT_VERSION;
#endif
	qreply(q, reply);
	break;

    case DL_ATTACH_REQ:
	if (size < sizeof(dl_attach_req_t))
	    goto badprim;
	if (us->state != DL_UNATTACHED || us->ppa != 0) {
	    dlpi_error(q, us, DL_ATTACH_REQ, DL_OUTSTATE, 0);
	    break;
	}
	for (ppa = ppas; ppa != 0; ppa = ppa->nextppa)
	    if (ppa->ppa_id == d->attach_req.dl_ppa)
		break;
	if (ppa == 0) {
	    dlpi_error(q, us, DL_ATTACH_REQ, DL_BADPPA, 0);
	    break;
	}
	us->ppa = ppa;
	qwriter(q, mp, attach_ppa, PERIM_OUTER);
	return;

    case DL_DETACH_REQ:
	if (size < sizeof(dl_detach_req_t))
	    goto badprim;
	if (us->state != DL_UNBOUND || us->ppa == 0) {
	    dlpi_error(q, us, DL_DETACH_REQ, DL_OUTSTATE, 0);
	    break;
	}
	qwriter(q, mp, detach_ppa, PERIM_OUTER);
	return;

    case DL_BIND_REQ:
	if (size < sizeof(dl_bind_req_t))
	    goto badprim;
	if (us->state != DL_UNBOUND || us->ppa == 0) {
	    dlpi_error(q, us, DL_BIND_REQ, DL_OUTSTATE, 0);
	    break;
	}
#if 0
	/* apparently this test fails (unnecessarily?) on some systems */
	if (d->bind_req.dl_service_mode != DL_CLDLS) {
	    dlpi_error(q, us, DL_BIND_REQ, DL_UNSUPPORTED, 0);
	    break;
	}
#endif

	/* saps must be valid PPP network protocol numbers,
	   except that we accept ETHERTYPE_IP in place of PPP_IP. */
	sap = d->bind_req.dl_sap;
	us->req_sap = sap;

#if defined(SOL2)
	if (us->flags & US_DBGLOG)
	    DPRINT2("DL_BIND_REQ: ip gives sap = 0x%x, us = 0x%x", sap, us);

	if (sap == ETHERTYPE_IP)	    /* normal IFF_IPV4 */
	    sap = PPP_IP;
	else if (sap == ETHERTYPE_IPV6)	    /* when IFF_IPV6 is set */
	    sap = PPP_IPV6;
	else if (sap == ETHERTYPE_ALLSAP)   /* snoop gives sap of 0 */
	    sap = PPP_ALLSAP;
	else {
	    DPRINT2("DL_BIND_REQ: unrecognized sap = 0x%x, us = 0x%x", sap, us);
	    dlpi_error(q, us, DL_BIND_REQ, DL_BADADDR, 0);
	    break;
	}
#else
	if (sap == ETHERTYPE_IP)
	    sap = PPP_IP;
	if (sap < 0x21 || sap > 0x3fff || (sap & 0x101) != 1) {
	    dlpi_error(q, us, DL_BIND_REQ, DL_BADADDR, 0);
	    break;
	}
#endif /* defined(SOL2) */

	/* check that no other stream is bound to this sap already. */
	for (os = us->ppa; os != 0; os = os->next)
	    if (os->sap == sap)
		break;
	if (os != 0) {
	    dlpi_error(q, us, DL_BIND_REQ, DL_NOADDR, 0);
	    break;
	}

	us->sap = sap;
	us->state = DL_IDLE;

	if ((reply = allocb(sizeof(dl_bind_ack_t) + sizeof(uint),
			    BPRI_HI)) == 0)
	    break;		/* should do bufcall */
	ackp = (dl_bind_ack_t *) reply->b_wptr;
	reply->b_wptr += sizeof(dl_bind_ack_t) + sizeof(uint);
	reply->b_datap->db_type = M_PCPROTO;
	bzero((caddr_t) ackp, sizeof(dl_bind_ack_t));
	ackp->dl_primitive = DL_BIND_ACK;
	ackp->dl_sap = sap;
	ackp->dl_addr_length = sizeof(uint);
	ackp->dl_addr_offset = sizeof(dl_bind_ack_t);
	*(uint *)(ackp+1) = sap;
	qreply(q, reply);
	break;

    case DL_UNBIND_REQ:
	if (size < sizeof(dl_unbind_req_t))
	    goto badprim;
	if (us->state != DL_IDLE) {
	    dlpi_error(q, us, DL_UNBIND_REQ, DL_OUTSTATE, 0);
	    break;
	}
	us->sap = -1;
	us->state = DL_UNBOUND;
#ifdef LACHTCP
	us->ppa->ifstats.ifs_active = 0;
#endif
	dlpi_ok(q, DL_UNBIND_REQ);
	break;

    case DL_UNITDATA_REQ:
	if (size < sizeof(dl_unitdata_req_t))
	    goto badprim;
	if (us->state != DL_IDLE) {
	    dlpi_error(q, us, DL_UNITDATA_REQ, DL_OUTSTATE, 0);
	    break;
	}
	if ((ppa = us->ppa) == 0) {
	    cmn_err(CE_CONT, "ppp: in state dl_idle but ppa == 0?\n");
	    break;
	}
	len = mp->b_cont == 0? 0: msgdsize(mp->b_cont);
	if (len > ppa->mtu) {
	    DPRINT2("dlpi data too large (%d > %d)\n", len, ppa->mtu);
	    break;
	}

#if defined(SOL2)
	/*
	 * Should there be any promiscuous stream(s), send the data
	 * up for each promiscuous stream that we recognize.
	 */
	if (mp->b_cont)
	    promisc_sendup(ppa, mp->b_cont, us->sap, 0);
#endif /* defined(SOL2) */

	mp->b_band = 0;
#ifdef PRIOQ
        /* Extract s_port & d_port from IP-packet, the code is a bit
           dirty here, but so am I, too... */
        if (mp->b_datap->db_type == M_PROTO && us->sap == PPP_IP
	    && mp->b_cont != 0) {
	    u_char *bb, *tlh;
	    int iphlen, len;
	    u_short *ptr;
	    u_char band_unset, cur_band, syn;
	    u_short s_port, d_port;

            bb = mp->b_cont->b_rptr; /* bb points to IP-header*/
	    len = mp->b_cont->b_wptr - mp->b_cont->b_rptr;
            syn = 0;
	    s_port = IPPORT_DEFAULT;
	    d_port = IPPORT_DEFAULT;
	    if (len >= 20) {	/* 20 = minimum length of IP header */
		iphlen = (bb[0] & 0x0f) * 4;
		tlh = bb + iphlen;
		len -= iphlen;
		switch (bb[9]) {
		case IPPROTO_TCP:
		    if (len >= 20) {	      /* min length of TCP header */
			s_port = (tlh[0] << 8) + tlh[1];
			d_port = (tlh[2] << 8) + tlh[3];
			syn = tlh[13] & 0x02;
		    }
		    break;
		case IPPROTO_UDP:
		    if (len >= 8) {	      /* min length of UDP header */
			s_port = (tlh[0] << 8) + tlh[1];
			d_port = (tlh[2] << 8) + tlh[3];
		    }
		    break;
		}
	    }

            /*
	     * Now calculate b_band for this packet from the
	     * port-priority table.
	     */
            ptr = prioq_table;
            cur_band = max_band;
            band_unset = 1;
            while (*ptr) {
                while (*ptr && band_unset)
                    if (s_port == *ptr || d_port == *ptr++) {
                        mp->b_band = cur_band;
                        band_unset = 0;
                        break;
		    }
                ptr++;
                cur_band--;
	    }
            if (band_unset)
		mp->b_band = def_band;
            /* It may be usable to urge SYN packets a bit */
            if (syn)
		mp->b_band++;
	}
#endif	/* PRIOQ */
	/* this assumes PPP_HDRLEN <= sizeof(dl_unitdata_req_t) */
	if (mp->b_datap->db_ref > 1) {
	    np = allocb(PPP_HDRLEN, BPRI_HI);
	    if (np == 0)
		break;		/* gak! */
	    np->b_cont = mp->b_cont;
	    mp->b_cont = 0;
	    freeb(mp);
	    mp = np;
	} else
	    mp->b_datap->db_type = M_DATA;
	/* XXX should use dl_dest_addr_offset/length here,
	   but we would have to translate ETHERTYPE_IP -> PPP_IP */
	mp->b_wptr = mp->b_rptr + PPP_HDRLEN;
	mp->b_rptr[0] = PPP_ALLSTATIONS;
	mp->b_rptr[1] = PPP_UI;
	mp->b_rptr[2] = us->sap >> 8;
	mp->b_rptr[3] = us->sap;
	if (pass_packet(us, mp, 1)) {
	    if (!send_data(mp, us))
		putq(q, mp);
	}
	return;

#if DL_CURRENT_VERSION >= 2
    case DL_PHYS_ADDR_REQ:
	if (size < sizeof(dl_phys_addr_req_t))
	    goto badprim;

	/*
	 * Don't check state because ifconfig sends this one down too
	 */

	if ((reply = allocb(sizeof(dl_phys_addr_ack_t)+ETHERADDRL, 
			BPRI_HI)) == 0)
	    break;		/* should do bufcall */
	reply->b_datap->db_type = M_PCPROTO;
	paddrack = (dl_phys_addr_ack_t *) reply->b_wptr;
	reply->b_wptr += sizeof(dl_phys_addr_ack_t);
	bzero((caddr_t) paddrack, sizeof(dl_phys_addr_ack_t)+ETHERADDRL);
	paddrack->dl_primitive = DL_PHYS_ADDR_ACK;
	paddrack->dl_addr_length = ETHERADDRL;
	paddrack->dl_addr_offset = sizeof(dl_phys_addr_ack_t);
	bcopy(&eaddr, reply->b_wptr, ETHERADDRL);
	reply->b_wptr += ETHERADDRL;
	qreply(q, reply);
	break;

#if defined(SOL2)
    case DL_PROMISCON_REQ:
	if (size < sizeof(dl_promiscon_req_t))
	    goto badprim;
	us->flags |= US_PROMISC;
	dlpi_ok(q, DL_PROMISCON_REQ);
	break;

    case DL_PROMISCOFF_REQ:
	if (size < sizeof(dl_promiscoff_req_t))
	    goto badprim;
	us->flags &= ~US_PROMISC;
	dlpi_ok(q, DL_PROMISCOFF_REQ);
	break;
#else
    case DL_PROMISCON_REQ:	    /* fall thru */
    case DL_PROMISCOFF_REQ:	    /* fall thru */
#endif /* defined(SOL2) */
#endif /* DL_CURRENT_VERSION >= 2 */

#if DL_CURRENT_VERSION >= 2
    case DL_SET_PHYS_ADDR_REQ:
    case DL_SUBS_BIND_REQ:
    case DL_SUBS_UNBIND_REQ:
    case DL_ENABMULTI_REQ:
    case DL_DISABMULTI_REQ:
    case DL_XID_REQ:
    case DL_TEST_REQ:
    case DL_REPLY_UPDATE_REQ:
    case DL_REPLY_REQ:
    case DL_DATA_ACK_REQ:
#endif
    case DL_CONNECT_REQ:
    case DL_TOKEN_REQ:
	dlpi_error(q, us, d->dl_primitive, DL_NOTSUPPORTED, 0);
	break;

    case DL_CONNECT_RES:
    case DL_DISCONNECT_REQ:
    case DL_RESET_REQ:
    case DL_RESET_RES:
	dlpi_error(q, us, d->dl_primitive, DL_OUTSTATE, 0);
	break;

    case DL_UDQOS_REQ:
	dlpi_error(q, us, d->dl_primitive, DL_BADQOSTYPE, 0);
	break;

#if DL_CURRENT_VERSION >= 2
    case DL_TEST_RES:
    case DL_XID_RES:
	break;
#endif

    default:
	cmn_err(CE_CONT, "ppp: unknown dlpi prim 0x%x\n", d->dl_primitive);
	/* fall through */
    badprim:
	dlpi_error(q, us, d->dl_primitive, DL_BADPRIM, 0);
	break;
    }
    freemsg(mp);
}

static void
dlpi_error(q, us, prim, err, uerr)
    queue_t *q;
    upperstr_t *us;
    int prim, err, uerr;
{
    mblk_t *reply;
    dl_error_ack_t *errp;

    if (us->flags & US_DBGLOG)
        DPRINT3("ppp/%d: dlpi error, prim=%x, err=%x\n", us->mn, prim, err);
    reply = allocb(sizeof(dl_error_ack_t), BPRI_HI);
    if (reply == 0)
	return;			/* XXX should do bufcall */
    reply->b_datap->db_type = M_PCPROTO;
    errp = (dl_error_ack_t *) reply->b_wptr;
    reply->b_wptr += sizeof(dl_error_ack_t);
    errp->dl_primitive = DL_ERROR_ACK;
    errp->dl_error_primitive = prim;
    errp->dl_errno = err;
    errp->dl_unix_errno = uerr;
    qreply(q, reply);
}

static void
dlpi_ok(q, prim)
    queue_t *q;
    int prim;
{
    mblk_t *reply;
    dl_ok_ack_t *okp;

    reply = allocb(sizeof(dl_ok_ack_t), BPRI_HI);
    if (reply == 0)
	return;			/* XXX should do bufcall */
    reply->b_datap->db_type = M_PCPROTO;
    okp = (dl_ok_ack_t *) reply->b_wptr;
    reply->b_wptr += sizeof(dl_ok_ack_t);
    okp->dl_primitive = DL_OK_ACK;
    okp->dl_correct_primitive = prim;
    qreply(q, reply);
}
#endif /* NO_DLPI */

static int
pass_packet(us, mp, outbound)
    upperstr_t *us;
    mblk_t *mp;
    int outbound;
{
    int pass;
    upperstr_t *ppa;

    if ((ppa = us->ppa) == 0) {
	freemsg(mp);
	return 0;
    }

#ifdef FILTER_PACKETS
    pass = ip_hard_filter(us, mp, outbound);
#else