if.c

<B>Digital的Unix操作系统VAX 4.2源码</B>

 * Mark an interface down and notify protocols of
 * the transition. Change routes.
 * NOTE: must be called at splnet or eqivalent.
 */
if_down(ifp)
	register struct ifnet *ifp;
{
	register struct ifaddr *ifa;

	ifp->if_flags &= ~IFF_UP;
	for (ifa = ifp->if_addrlist; ifa; ifa = ifa->ifa_next) {
		pfctlinput(PRC_ROUTEDEAD, (caddr_t)&ifa->ifa_addr);
	}
}

/*
 * Handle interface watchdog timer routines.  Called
 * from softclock, we decrement timers (if set) and
 * call the appropriate interface routine on expiration.
 */
if_slowtimo()
{
	register struct ifnet *ifp;
	int saveaffinity;

	for (ifp = ifnet; ifp; ifp = ifp->if_next) {
		if (ifp->if_timer == 0 || --ifp->if_timer)
			continue;
		if (ifp->if_watchdog){
			CALL_TO_NONSMP_DRIVER( (*ifp), saveaffinity);
			(*ifp->if_watchdog)(ifp->if_unit);
			RETURN_FROM_NONSMP_DRIVER( (*ifp), saveaffinity);
		}
	}
	timeout(if_slowtimo, (caddr_t)0, hz / IFNET_SLOWHZ);
}

/*
 * Map interface name to
 * interface structure pointer.
 */
struct ifnet *
ifunit(name)
	register char *name;
{
	register char *cp, *cp2;
	register struct ifnet *ifp;
	int unit;

	for (cp = name; cp < name + IFNAMSIZ && *cp; cp++)
		if (*cp >= '0' && *cp <= '9')
			break;
	if (*cp == '\0' || cp == name + IFNAMSIZ)
		return ((struct ifnet *)0);
	for (unit = 0, cp2 = cp; cp2 < name + IFNAMSIZ && *cp2; cp2++)
		unit = unit * 10 + (*cp2 - '0');
	for (ifp = ifnet; ifp; ifp = ifp->if_next) {
	        if ((unsigned)(cp - name) != strlen(ifp->if_name))
		        continue;
		/*
		 * Following lines for se/ln compatibility
		 */
		if (((unsigned)(cp - name) == 2) && (!bcmp(name, "se", 2))) {
			if (bcmp(ifp->if_name, "ln", 2))
				continue;
		} else {
			if (bcmp(ifp->if_name, name, (unsigned)(cp - name)))
				continue;
		}
		if (unit == ifp->if_unit)
			break;
	}
	return (ifp);
}

/*
 *  From an ifp, generate the name of an interface.
 */
ifname(ifp, name)
    struct ifnet *ifp;
    char *name;
{
    register int i = 0, unit = ifp->if_unit;
    char digits[6], *p = ifp->if_name;

    /*
     *  Copy the interfaces base name (assume everythings ok).
     */
    while (*p)
	*name++ = *p++;
    /*
     *  Calculate the unit's digits in reverse order.
     */
    do {
	digits[i++] = (unit % 10) + '0';
	unit = unit/10;
    } while (unit);

    /*
     * Append the digits in reverse order.  This will
     * result in a correct number.
     */
    while (i--)
	*name++ = digits[i];
    *name = '\0';
}

/*
 * Interface ioctls.
 */
ifioctl(so, cmd, data)
	struct socket *so;
	int cmd;
	caddr_t data;
{
	register struct ifnet *ifp;
	register struct ifreq *ifr;
	int saveaffinity;
	int error;
	int s;
	int owner = 0; /* SMP */

	switch (cmd) {

	case SIOCSCREENON:
	case SIOCSCREEN:
	case SIOCSCREENSTATS:
		return(screen_control(so, cmd, data, (struct ifnet *)0));

	case SIOCGIFCONF:
		if (smp_owner(&so->lk_socket)){
			smp_unlock(&so->lk_socket);
			owner=1;
		}
		error = ifconf(cmd,data);
		if (owner) {
			SO_LOCK(so);
		}
		return (error);

#if defined(INET) && ( NETHER > 0 || NFDDI > 0)
	case SIOCSARP:
	case SIOCDARP:
		if (!suser())
			return (u.u_error);
		/* FALL THROUGH */
	case SIOCGARP:
		return (arpioctl(cmd, data));
#endif
	}
	ifr = (struct ifreq *)data;
	ifp = ifunit(ifr->ifr_name);
	if (ifp == 0)
		return (ENXIO);
	switch (cmd) {

	case SIOCGIFFLAGS:
		ifr->ifr_flags = ifp->if_flags;
		break;

	case SIOCGIFMETRIC:
		ifr->ifr_metric = ifp->if_metric;
		break;

	case SIOCSIFFLAGS:
		if (!suser())
			return (u.u_error);
		if (ifp->if_flags & IFF_UP && (ifr->ifr_flags & IFF_UP) == 0) {
			s = splnet();
			/*
			 * must obey lock ordering
			 */
			if (smp_owner(&so->lk_socket)){
			  so->ref = 32;
			  owner = 1;
			  smp_unlock(&so->lk_socket);
			}
			if_down(ifp);
			if (owner){
			  smp_lock(&so->lk_socket,LK_RETRY);
			  so->ref = 0;
			  owner = 0;
			}
			splx(s);
		}
		if ((ifr->ifr_flags & IFF_802HDR) &&
		    (ifp->if_type == IFT_ETHER)) {
			s = splnet();
			ifp->if_type = IFT_ISO88023;
			ifp->if_flags &= (IFF_NOTRAILERS|IFF_802HDR);
			ifp->if_mtu = ETHERMTU - sizeof (struct llc);
			splx(s);
		}
		ifp->if_flags = (ifp->if_flags & IFF_CANTCHANGE) |
			(ifr->ifr_flags &~ IFF_CANTCHANGE);
		/* Note that we don't do an affinity flag check here as
		 * an optimization where if set, we could go to the driver 
		 * without unlocking.  The reason we do not do that here, 
		 * is that so far, the network drivers can sleep for DECnet. 
		 * When we eleminate sleeps in the drivers, we can delete the
		 * owner check and unlocks here.
		 */
		if (smp_owner(&so->lk_socket)){
			so->ref = 8;
			owner = 1;
			smp_unlock(&so->lk_socket);
		}
	        if (ifp->if_ioctl){
			CALL_TO_NONSMP_DRIVER( (*ifp), saveaffinity);
			(void) (*ifp->if_ioctl)(ifp, cmd, data);
			RETURN_FROM_NONSMP_DRIVER( (*ifp), saveaffinity);
		}
		if (owner){
			smp_lock(&so->lk_socket,LK_RETRY);
			so->ref = 0;
			owner = 0;
		}
		break;
	case SIOCSIFMETRIC:
		if (!suser())
			return (u.u_error);
		ifp->if_metric = ifr->ifr_metric;
		break;
        case SIOCENABLBACK:
        case SIOCDISABLBACK:
	case SIOCSPHYSADDR: 
	case SIOCDELMULTI: 
	case SIOCADDMULTI: 
	case SIOCRDZCTRS:
	case SIOCIFRESET:
	case SIOCEEUPDATE:
		if(!suser())
			return(u.u_error);
		/* FALL THROUGH */
	case SIOCRDCTRS:
        case SIOCRPHYSADDR: 
		if (ifp->if_ioctl == 0)
			return (EOPNOTSUPP);
		if (smp_owner(&so->lk_socket)){
			owner = 1;
			so->ref = 8;
			smp_unlock(&so->lk_socket);
			}
		CALL_TO_NONSMP_DRIVER( (*ifp), saveaffinity);
		error = (*ifp->if_ioctl)(ifp, cmd, data);
		RETURN_FROM_NONSMP_DRIVER( (*ifp), saveaffinity);
		if (owner){
			smp_lock(&so->lk_socket,LK_RETRY);
			so->ref = 0;
			owner = 0;
			}
		return(error);
	case SIOCARPREQ:
		if (suser())
			if (nINET == 1)
				return (arpwhohas(ifp,ifr->ifr_addr.sa_data));
			else
				return (ENETDOWN);
		else
			return (EACCES);


	/*
	 * protocol specific ioctls that must deal with the interface
	 * are handled in the default case by the protocol specific
	 * usrreq routine.
	 */
	default:  
		if (so->so_proto == 0)  {
			mprintf("ifioctl: no socket proto\n");
			return (EOPNOTSUPP);
		}
		return ((*so->so_proto->pr_usrreq)(so, PRU_CONTROL,
			cmd, data, ifp));
	}
	return (0);
}

/*
 * Return interface configuration
 * of system.  List may be used
 * in later ioctl's (above) to get
 * other information.
 */
/*ARGSUSED*/
ifconf(cmd, data)
	int cmd;
	caddr_t data;
{
	register struct ifconf *ifc = (struct ifconf *)data;
	register struct ifnet *ifp = ifnet;
	register struct ifaddr *ifa;
	struct ifreq ifr, *ifrp;
	struct ifreq *u_sptr, *u_tmp ;
	int space = ifc->ifc_len;
	int space_tmp = ifc->ifc_len;
	int s;
	int error;

	KM_ALLOC( u_sptr, struct ifreq *, space, KM_TEMP, KM_CLEAR);
	u_tmp = u_sptr;
	ifrp = ifc->ifc_req;

	for (; space > sizeof (ifr) && ifp; ifp = ifp->if_next) {
		ifname(ifp, ifr.ifr_name);
		if ((ifa = ifp->if_addrlist) == 0) {
			bzero((caddr_t)&ifr.ifr_addr, sizeof(ifr.ifr_addr));
			/* bcopy((caddr_t)&ifr, (caddr_t)ifrp, sizeof (ifr)); */
			bcopy((caddr_t)&ifr, (caddr_t)u_sptr, sizeof (ifr)); 
			space -= sizeof (ifr), u_sptr++;
		} else 
		    for ( ; space > sizeof (ifr) && ifa; ifa = ifa->ifa_next) {
			ifr.ifr_addr = ifa->ifa_addr;
			bcopy((caddr_t)&ifr, (caddr_t)u_sptr, sizeof (ifr));
			space -= sizeof (ifr), u_sptr++;
		}
	}

	error =copyout((caddr_t)u_tmp, (caddr_t)ifrp, ifc->ifc_len-space);
	KM_FREE(u_tmp, KM_TEMP);
	ifc->ifc_len -= space;

	return (error);
}