if_spppsubr.c

基于组件方式开发操作系统的OSKIT源代码

#endif
#ifdef NS
		case PPP_XNS:
			/* XNS IDPCP not implemented yet */
			if (sp->pp_phase == PHASE_NETWORK) {
				schednetisr (NETISR_NS);
				inq = &nsintrq;
			}
			break;
#endif
#ifdef ISO
		case PPP_ISO:
			/* OSI NLCP not implemented yet */
			if (sp->pp_phase == PHASE_NETWORK) {
				schednetisr (NETISR_ISO);
				inq = &clnlintrq;
			}
			break;
#endif
		}
		break;
	case CISCO_MULTICAST:
	case CISCO_UNICAST:
		/* Don't check the control field here (RFC 1547). */
		if (! (sp->pp_flags & PP_CISCO)) {
			if (debug)
				log(LOG_DEBUG,
				    SPP_FMT "Cisco packet in PPP mode "
				    "<addr=0x%x ctrl=0x%x proto=0x%x>\n",
				    SPP_ARGS(ifp),
				    h->address, h->control, ntohs(h->protocol));
			goto drop;
		}
		switch (ntohs (h->protocol)) {
		default:
			++ifp->if_noproto;
			goto invalid;
		case CISCO_KEEPALIVE:
			sppp_cisco_input ((struct sppp*) ifp, m);
			m_freem (m);
			return;
#ifdef INET
		case ETHERTYPE_IP:
			schednetisr (NETISR_IP);
			inq = &ipintrq;
			break;
#endif
#ifdef IPX
		case ETHERTYPE_IPX:
			schednetisr (NETISR_IPX);
			inq = &ipxintrq;
			break;
#endif
#ifdef NS
		case ETHERTYPE_NS:
			schednetisr (NETISR_NS);
			inq = &nsintrq;
			break;
#endif
		}
		break;
	default:        /* Invalid PPP packet. */
	  invalid:
		if (debug)
			log(LOG_DEBUG,
			    SPP_FMT "invalid input packet "
			    "<addr=0x%x ctrl=0x%x proto=0x%x>\n",
			    SPP_ARGS(ifp),
			    h->address, h->control, ntohs(h->protocol));
		goto drop;
	}

	if (! (ifp->if_flags & IFF_UP) || ! inq)
		goto drop;

	/* Check queue. */
	s = splimp();
	if (IF_QFULL (inq)) {
		/* Queue overflow. */
		IF_DROP(inq);
		splx(s);
		if (debug)
			log(LOG_DEBUG, SPP_FMT "protocol queue overflow\n",
				SPP_ARGS(ifp));
		goto drop;
	}
	IF_ENQUEUE(inq, m);
	splx(s);
}

/*
 * Enqueue transmit packet.
 */
static int
sppp_output(struct ifnet *ifp, struct mbuf *m,
	    struct sockaddr *dst, struct rtentry *rt)
{
	struct sppp *sp = (struct sppp*) ifp;
	struct ppp_header *h;
	struct ifqueue *ifq;
	int s, rv = 0;
	int debug = ifp->if_flags & IFF_DEBUG;

	s = splimp();

	if ((ifp->if_flags & IFF_UP) == 0 ||
	    (ifp->if_flags & (IFF_RUNNING | IFF_AUTO)) == 0) {
		m_freem (m);
		splx (s);
		return (ENETDOWN);
	}

	if ((ifp->if_flags & (IFF_RUNNING | IFF_AUTO)) == IFF_AUTO) {
		/*
		 * Interface is not yet running, but auto-dial.  Need
		 * to start LCP for it.
		 */
		ifp->if_flags |= IFF_RUNNING;
		splx(s);
		lcp.Open(sp);
		s = splimp();
	}

	ifq = &ifp->if_snd;
#ifdef INET
	if (dst->sa_family == AF_INET) {
		/* XXX Check mbuf length here? */
		struct ip *ip = mtod (m, struct ip*);
		struct tcphdr *tcp = (struct tcphdr*) ((long*)ip + ip->ip_hl);

		/*
		 * When using dynamic local IP address assignment by using
		 * 0.0.0.0 as a local address, the first TCP session will
		 * not connect because the local TCP checksum is computed
		 * using 0.0.0.0 which will later become our real IP address
		 * so the TCP checksum computed at the remote end will
		 * become invalid. So we
		 * - don't let packets with src ip addr 0 thru
		 * - we flag TCP packets with src ip 0 as an error
		 */	

		if(ip->ip_src.s_addr == INADDR_ANY)	/* -hm */
		{
			m_freem(m);
			splx(s);
			if(ip->ip_p == IPPROTO_TCP)
				return(EADDRNOTAVAIL);
			else
				return(0);
		}
		
		/*
		 * Put low delay, telnet, rlogin and ftp control packets
		 * in front of the queue.
		 */
		if (IF_QFULL (&sp->pp_fastq))
			;
		else if (ip->ip_tos & IPTOS_LOWDELAY)
			ifq = &sp->pp_fastq;
		else if (m->m_len < sizeof *ip + sizeof *tcp)
			;
		else if (ip->ip_p != IPPROTO_TCP)
			;
		else if (INTERACTIVE (ntohs (tcp->th_sport)))
			ifq = &sp->pp_fastq;
		else if (INTERACTIVE (ntohs (tcp->th_dport)))
			ifq = &sp->pp_fastq;
	}
#endif

	/*
	 * Prepend general data packet PPP header. For now, IP only.
	 */
	M_PREPEND (m, PPP_HEADER_LEN, M_DONTWAIT);
	if (! m) {
		if (debug)
			log(LOG_DEBUG, SPP_FMT "no memory for transmit header\n",
				SPP_ARGS(ifp));
		++ifp->if_oerrors;
		splx (s);
		return (ENOBUFS);
	}
	/*
	 * May want to check size of packet
	 * (albeit due to the implementation it's always enough)
	 */
	h = mtod (m, struct ppp_header*);
	if (sp->pp_flags & PP_CISCO) {
		h->address = CISCO_UNICAST;        /* unicast address */
		h->control = 0;
	} else {
		h->address = PPP_ALLSTATIONS;        /* broadcast address */
		h->control = PPP_UI;                 /* Unnumbered Info */
	}

	switch (dst->sa_family) {
#ifdef INET
	case AF_INET:   /* Internet Protocol */
		if (sp->pp_flags & PP_CISCO)
			h->protocol = htons (ETHERTYPE_IP);
		else {
			/*
			 * Don't choke with an ENETDOWN early.  It's
			 * possible that we just started dialing out,
			 * so don't drop the packet immediately.  If
			 * we notice that we run out of buffer space
			 * below, we will however remember that we are
			 * not ready to carry IP packets, and return
			 * ENETDOWN, as opposed to ENOBUFS.
			 */
			h->protocol = htons(PPP_IP);
			if (sp->state[IDX_IPCP] != STATE_OPENED)
				rv = ENETDOWN;
		}
		break;
#endif
#ifdef NS
	case AF_NS:     /* Xerox NS Protocol */
		h->protocol = htons ((sp->pp_flags & PP_CISCO) ?
			ETHERTYPE_NS : PPP_XNS);
		break;
#endif
#ifdef IPX
	case AF_IPX:     /* Novell IPX Protocol */
		h->protocol = htons ((sp->pp_flags & PP_CISCO) ?
			ETHERTYPE_IPX : PPP_IPX);
		break;
#endif
#ifdef ISO
	case AF_ISO:    /* ISO OSI Protocol */
		if (sp->pp_flags & PP_CISCO)
			goto nosupport;
		h->protocol = htons (PPP_ISO);
		break;
nosupport:
#endif
	default:
		m_freem (m);
		++ifp->if_oerrors;
		splx (s);
		return (EAFNOSUPPORT);
	}

	/*
	 * Queue message on interface, and start output if interface
	 * not yet active.
	 */
	if (IF_QFULL (ifq)) {
		IF_DROP (&ifp->if_snd);
		m_freem (m);
		++ifp->if_oerrors;
		splx (s);
		return (rv? rv: ENOBUFS);
	}
	IF_ENQUEUE (ifq, m);
	if (! (ifp->if_flags & IFF_OACTIVE))
		(*ifp->if_start) (ifp);

	/*
	 * Count output packets and bytes.
	 * The packet length includes header, FCS and 1 flag,
	 * according to RFC 1333.
	 */
	ifp->if_obytes += m->m_pkthdr.len + 3;
	splx (s);
	return (0);
}

void
sppp_attach(struct ifnet *ifp)
{
	struct sppp *sp = (struct sppp*) ifp;

	/* Initialize keepalive handler. */
	if (! spppq)
		TIMEOUT(sppp_keepalive, 0, hz * 10, keepalive_ch);

	/* Insert new entry into the keepalive list. */
	sp->pp_next = spppq;
	spppq = sp;

	sp->pp_if.if_mtu = PP_MTU;
	sp->pp_if.if_flags = IFF_POINTOPOINT | IFF_MULTICAST;
	sp->pp_if.if_type = IFT_PPP;
	sp->pp_if.if_output = sppp_output;
#if 0
	sp->pp_flags = PP_KEEPALIVE;
#endif
	sp->pp_fastq.ifq_maxlen = 32;
	sp->pp_cpq.ifq_maxlen = 20;
	sp->pp_loopcnt = 0;
	sp->pp_alivecnt = 0;
	sp->pp_seq = 0;
	sp->pp_rseq = 0;
	sp->pp_phase = PHASE_DEAD;
	sp->pp_up = lcp.Up;
	sp->pp_down = lcp.Down;

	sppp_lcp_init(sp);
	sppp_ipcp_init(sp);
	sppp_pap_init(sp);
	sppp_chap_init(sp);
}

void
sppp_detach(struct ifnet *ifp)
{
	struct sppp **q, *p, *sp = (struct sppp*) ifp;
	int i;

	/* Remove the entry from the keepalive list. */
	for (q = &spppq; (p = *q); q = &p->pp_next)
		if (p == sp) {
			*q = p->pp_next;
			break;
		}

	/* Stop keepalive handler. */
	if (! spppq)
		UNTIMEOUT(sppp_keepalive, 0, keepalive_ch);

	for (i = 0; i < IDX_COUNT; i++)
		UNTIMEOUT((cps[i])->TO, (void *)sp, sp->ch[i]);
	UNTIMEOUT(sppp_pap_my_TO, (void *)sp, sp->pap_my_to_ch);
}

/*
 * Flush the interface output queue.
 */
void
sppp_flush(struct ifnet *ifp)
{
	struct sppp *sp = (struct sppp*) ifp;

	sppp_qflush (&sp->pp_if.if_snd);
	sppp_qflush (&sp->pp_fastq);
	sppp_qflush (&sp->pp_cpq);
}

/*
 * Check if the output queue is empty.
 */
int
sppp_isempty(struct ifnet *ifp)
{
	struct sppp *sp = (struct sppp*) ifp;
	int empty, s;

	s = splimp();
	empty = !sp->pp_fastq.ifq_head && !sp->pp_cpq.ifq_head &&
		!sp->pp_if.if_snd.ifq_head;
	splx(s);
	return (empty);
}

/*
 * Get next packet to send.
 */
struct mbuf *
sppp_dequeue(struct ifnet *ifp)
{
	struct sppp *sp = (struct sppp*) ifp;
	struct mbuf *m;
	int s;

	s = splimp();
	/*
	 * Process only the control protocol queue until we have at
	 * least one NCP open.
	 *
	 * Do always serve all three queues in Cisco mode.
	 */
	IF_DEQUEUE(&sp->pp_cpq, m);
	if (m == NULL &&
	    (sppp_ncp_check(sp) || (sp->pp_flags & PP_CISCO) != 0)) {
		IF_DEQUEUE(&sp->pp_fastq, m);
		if (m == NULL)
			IF_DEQUEUE (&sp->pp_if.if_snd, m);
	}
	splx(s);
	return m;
}

/*
 * Pick the next packet, do not remove it from the queue.
 */
struct mbuf *
sppp_pick(struct ifnet *ifp)
{
	struct sppp *sp = (struct sppp*)ifp;
	struct mbuf *m;
	int s;

	s= splimp ();

	m = sp->pp_cpq.ifq_head;
	if (m == NULL &&
	    (sp->pp_phase == PHASE_NETWORK ||
	     (sp->pp_flags & PP_CISCO) != 0))
		if ((m = sp->pp_fastq.ifq_head) == NULL)
			m = sp->pp_if.if_snd.ifq_head;
	splx (s);
	return (m);
}

/*
 * Process an ioctl request.  Called on low priority level.
 */
int
sppp_ioctl(struct ifnet *ifp, IOCTL_CMD_T cmd, void *data)
{
	struct ifreq *ifr = (struct ifreq*) data;
	struct sppp *sp = (struct sppp*) ifp;
	int s, rv, going_up, going_down, newmode;

	s = splimp();
	rv = 0;
	switch (cmd) {
	case SIOCAIFADDR:
	case SIOCSIFDSTADDR:
		break;

	case SIOCSIFADDR:
		if_up(ifp);
		/* fall through... */

	case SIOCSIFFLAGS:
		going_up = ifp->if_flags & IFF_UP &&
			(ifp->if_flags & IFF_RUNNING) == 0;
		going_down = (ifp->if_flags & IFF_UP) == 0 &&
			ifp->if_flags & IFF_RUNNING;
		newmode = ifp->if_flags & (IFF_AUTO | IFF_PASSIVE);
		if (newmode == (IFF_AUTO | IFF_PASSIVE)) {
			/* sanity */
			newmode = IFF_PASSIVE;
			ifp->if_flags &= ~IFF_AUTO;
		}

		if (going_up || going_down)
			lcp.Close(sp);
		if (going_up && newmode == 0) {
			/* neither auto-dial nor passive */
			ifp->if_flags |= IFF_RUNNING;
			if (!(sp->pp_flags & PP_CISCO))
				lcp.Open(sp);
		} else if (going_down) {
			sppp_flush(ifp);
			ifp->if_flags &= ~IFF_RUNNING;
		}

		break;

#ifdef SIOCSIFMTU
#ifndef ifr_mtu
#define ifr_mtu ifr_metric
#endif
	case SIOCSIFMTU:
		if (ifr->ifr_mtu < 128 || ifr->ifr_mtu > sp->lcp.their_mru)
			return (EINVAL);
		ifp->if_mtu = ifr->ifr_mtu;
		break;
#endif
#ifdef SLIOCSETMTU
	case SLIOCSETMTU:
		if (*(short*)data < 128 || *(short*)data > sp->lcp.their_mru)
			return (EINVAL);
		ifp->if_mtu = *(short*)data;
		break;
#endif
#ifdef SIOCGIFMTU
	case SIOCGIFMTU:
		ifr->ifr_mtu = ifp->if_mtu;
		break;
#endif
#ifdef SLIOCGETMTU
	case SLIOCGETMTU:
		*(short*)data = ifp->if_mtu;
		break;
#endif
	case SIOCADDMULTI:
	case SIOCDELMULTI:
		break;

	case SIOCGIFGENERIC:
	case SIOCSIFGENERIC:
		rv = sppp_params(sp, cmd, data);
		break;

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


/*
 * Cisco framing implementation.
 */

/*
 * Handle incoming Cisco keepalive protocol packets.
 */
static void
sppp_cisco_input(struct sppp *sp, struct mbuf *m)
{
	STDDCL;
	struct cisco_packet *h;
	u_long me, mymask;

	if (m->m_pkthdr.len < CISCO_PACKET_LEN) {
		if (debug)
			log(LOG_DEBUG,
			    SPP_FMT "cisco invalid packet length: %d bytes\n",
			    SPP_ARGS(ifp), m->m_pkthdr.len);
		return;
	}
	h = mtod (m, struct cisco_packet*);
	if (debug)
		log(LOG_DEBUG,
		    SPP_FMT "cisco input: %d bytes "
		    "<0x%lx 0x%lx 0x%lx 0x%x 0x%x-0x%x>\n",
		    SPP_ARGS(ifp), m->m_pkthdr.len,
		    (u_long)ntohl (h->type), (u_long)h->par1, (u_long)h->par2, (u_int)h->rel,
		    (u_int)h->time0, (u_int)h->time1);
	switch (ntohl (h->type)) {