if.c

RTEMS (Real-Time Executive for Multiprocessor Systems) is a free open source real-time operating sys

 */
static void
if_qflush(ifq)
	register struct ifqueue *ifq;
{
	register struct mbuf *m, *n;

	n = ifq->ifq_head;
	while ((m = n) != 0) {
		n = m->m_act;
		m_freem(m);
	}
	ifq->ifq_head = 0;
	ifq->ifq_tail = 0;
	ifq->ifq_len = 0;
}

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

	for (ifp = ifnet; ifp; ifp = ifp->if_next) {
		if (ifp->if_timer == 0 || --ifp->if_timer)
			continue;
		if (ifp->if_watchdog)
			(*ifp->if_watchdog)(ifp);
	}
	splx(s);
	timeout(if_slowtimo, (void *)0, hz / IFNET_SLOWHZ);
}

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

	for (cp = name; cp < name + IFNAMSIZ && *cp; cp++)
		if (*cp >= '0' && *cp <= '9')
			break;
	if (*cp == '\0' || cp == name + IFNAMSIZ)
		return ((struct ifnet *)0);
	/*
	 * Save first char of unit, and pointer to it,
	 * so we can put a null there to avoid matching
	 * initial substrings of interface names.
	 */
	len = cp - name + 1;
	c = *cp;
	ep = cp;
	for (unit = 0; *cp >= '0' && *cp <= '9'; )
		unit = unit * 10 + *cp++ - '0';
	if (*cp != '\0')
		return 0;	/* no trailing garbage allowed */
	*ep = 0;
	for (ifp = ifnet; ifp; ifp = ifp->if_next) {
		if (bcmp(ifp->if_name, name, len))
			continue;
		if (unit == ifp->if_unit)
			break;
	}
	*ep = c;
	return (ifp);
}

/*
 * Interface ioctls.
 */
int
ifioctl(so, cmd, data, p)
	struct socket *so;
	int cmd;
	caddr_t data;
	struct proc *p;
{
	register struct ifnet *ifp;
	register struct ifreq *ifr;
	int error;

	switch (cmd) {

	case SIOCGIFCONF:
	case OSIOCGIFCONF:
		return (ifconf(cmd, data));
	}
	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 SIOCGIFMTU:
		ifr->ifr_mtu = ifp->if_mtu;
		break;

	case SIOCGIFPHYS:
		ifr->ifr_phys = ifp->if_physical;
		break;

	case SIOCSIFFLAGS:
		error = suser(p->p_ucred, &p->p_acflag);
		if (error)
			return (error);
		if (ifp->if_flags & IFF_UP && (ifr->ifr_flags & IFF_UP) == 0) {
			int s = splimp();
			if_down(ifp);
			splx(s);
		}
		if (ifr->ifr_flags & IFF_UP && (ifp->if_flags & IFF_UP) == 0) {
			int s = splimp();
			if_up(ifp);
			splx(s);
		}
		ifp->if_flags = (ifp->if_flags & IFF_CANTCHANGE) |
			(ifr->ifr_flags &~ IFF_CANTCHANGE);
		if (ifp->if_ioctl)
			(void) (*ifp->if_ioctl)(ifp, cmd, data);
		microtime(&ifp->if_lastchange);
		break;

	case SIOCSIFMETRIC:
		error = suser(p->p_ucred, &p->p_acflag);
		if (error)
			return (error);
		ifp->if_metric = ifr->ifr_metric;
		microtime(&ifp->if_lastchange);
		break;

	case SIOCSIFPHYS:
		error = suser(p->p_ucred, &p->p_acflag);
		if (error)
			return error;
		if (!ifp->if_ioctl)
		        return EOPNOTSUPP;
		error = (*ifp->if_ioctl)(ifp, cmd, data);
		if (error == 0)
			microtime(&ifp->if_lastchange);
		return(error);

	case SIOCSIFMTU:
		error = suser(p->p_ucred, &p->p_acflag);
		if (error)
			return (error);
		if (ifp->if_ioctl == NULL)
			return (EOPNOTSUPP);
		/*
		 * 72 was chosen below because it is the size of a TCP/IP
		 * header (40) + the minimum mss (32).
		 */
		if (ifr->ifr_mtu < 72 || ifr->ifr_mtu > 65535)
			return (EINVAL);
		error = (*ifp->if_ioctl)(ifp, cmd, data);
		if (error == 0)
			microtime(&ifp->if_lastchange);
		return(error);

	case SIOCADDMULTI:
	case SIOCDELMULTI:
		error = suser(p->p_ucred, &p->p_acflag);
		if (error)
			return (error);
		if (ifp->if_ioctl == NULL)
			return (EOPNOTSUPP);
		error = (*ifp->if_ioctl)(ifp, cmd, data);
		if (error == 0 )
		    	microtime(&ifp->if_lastchange);
		return(error);

        case SIOCSIFMEDIA:
		error = suser(p->p_ucred, &p->p_acflag);
		if (error)
			return (error);
		if (ifp->if_ioctl == 0)
			return (EOPNOTSUPP);
		error = (*ifp->if_ioctl)(ifp, cmd, data);
		if (error == 0)
			microtime(&ifp->if_lastchange);
		return error;

	case SIOCGIFMEDIA:
		if (ifp->if_ioctl == 0)
			return (EOPNOTSUPP);
		return ((*ifp->if_ioctl)(ifp, cmd, data));

	default:
		if (so->so_proto == 0)
			return (EOPNOTSUPP);
#ifndef COMPAT_43
		return ((*so->so_proto->pr_usrreqs->pru_control)(so, cmd,
								 data,
								 ifp));
#else
	    {
		int ocmd = cmd;

		switch (cmd) {

		case SIOCSIFDSTADDR:
		case SIOCSIFADDR:
		case SIOCSIFBRDADDR:
		case SIOCSIFNETMASK:
#if BYTE_ORDER != BIG_ENDIAN
			if (ifr->ifr_addr.sa_family == 0 &&
			    ifr->ifr_addr.sa_len < 16) {
				ifr->ifr_addr.sa_family = ifr->ifr_addr.sa_len;
				ifr->ifr_addr.sa_len = 16;
			}
#else
			if (ifr->ifr_addr.sa_len == 0)
				ifr->ifr_addr.sa_len = 16;
#endif
			break;

		case OSIOCGIFADDR:
			cmd = SIOCGIFADDR;
			break;

		case OSIOCGIFDSTADDR:
			cmd = SIOCGIFDSTADDR;
			break;

		case OSIOCGIFBRDADDR:
			cmd = SIOCGIFBRDADDR;
			break;

		case OSIOCGIFNETMASK:
			cmd = SIOCGIFNETMASK;
		}
		error =  ((*so->so_proto->pr_usrreqs->pru_control)(so,
								   cmd,
								   data,
								   ifp));
		switch (ocmd) {

		case OSIOCGIFADDR:
		case OSIOCGIFDSTADDR:
		case OSIOCGIFBRDADDR:
		case OSIOCGIFNETMASK:
			*(u_short *)&ifr->ifr_addr = ifr->ifr_addr.sa_family;
		}
		return (error);

	    }
#endif

	/*
	 * RTEMS additions for setting/getting `tap' function
	 */
	case SIOCSIFTAP:
		ifp->if_tap = ifr->ifr_tap;
		return 0;

	case SIOCGIFTAP:
		ifr->ifr_tap = ifp->if_tap;
		return 0;
	}
	return (0);
}

/*
 * Set/clear promiscuous mode on interface ifp based on the truth value
 * of pswitch.  The calls are reference counted so that only the first
 * "on" request actually has an effect, as does the final "off" request.
 * Results are undefined if the "off" and "on" requests are not matched.
 */
int
ifpromisc(ifp, pswitch)
	struct ifnet *ifp;
	int pswitch;
{
	struct ifreq ifr;

	if (pswitch) {
		/*
		 * If the device is not configured up, we cannot put it in
		 * promiscuous mode.
		 */
		if ((ifp->if_flags & IFF_UP) == 0)
			return (ENETDOWN);
		if (ifp->if_pcount++ != 0)
			return (0);
		ifp->if_flags |= IFF_PROMISC;
		log(LOG_INFO, "%s%d: promiscuous mode enabled\n",
		    ifp->if_name, ifp->if_unit);
	} else {
		if (--ifp->if_pcount > 0)
			return (0);
		ifp->if_flags &= ~IFF_PROMISC;
	}
	ifr.ifr_flags = ifp->if_flags;
	return ((*ifp->if_ioctl)(ifp, SIOCSIFFLAGS, (caddr_t)&ifr));
}

/*
 * Return interface configuration
 * of system.  List may be used
 * in later ioctl's (above) to get
 * other information.
 */
/*ARGSUSED*/
static int
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;
	int space = ifc->ifc_len, error = 0;

	ifrp = ifc->ifc_req;
	for (; space > sizeof (ifr) && ifp; ifp = ifp->if_next) {
		char workbuf[64];
		int ifnlen;

		ifnlen = sprintf(workbuf, "%s%d", ifp->if_name, ifp->if_unit);
		if(ifnlen + 1 > sizeof ifr.ifr_name) {
			error = ENAMETOOLONG;
		} else {
			strcpy(ifr.ifr_name, workbuf);
		}

		if ((ifa = ifp->if_addrlist) == 0) {
			bzero((caddr_t)&ifr.ifr_addr, sizeof(ifr.ifr_addr));
			error = copyout((caddr_t)&ifr, (caddr_t)ifrp,
			    sizeof (ifr));
			if (error)
				break;
			space -= sizeof (ifr), ifrp++;
		} else
		    for ( ; space > sizeof (ifr) && ifa; ifa = ifa->ifa_next) {
			register struct sockaddr *sa = ifa->ifa_addr;
#ifdef COMPAT_43
			if (cmd == OSIOCGIFCONF) {
				struct osockaddr *osa =
					 (struct osockaddr *)&ifr.ifr_addr;
				ifr.ifr_addr = *sa;
				osa->sa_family = sa->sa_family;
				error = copyout((caddr_t)&ifr, (caddr_t)ifrp,
						sizeof (ifr));
				ifrp++;
			} else
#endif
			if (sa->sa_len <= sizeof(*sa)) {
				ifr.ifr_addr = *sa;
				error = copyout((caddr_t)&ifr, (caddr_t)ifrp,
						sizeof (ifr));
				ifrp++;
			} else {
				space -= sa->sa_len - sizeof(*sa);
				if (space < sizeof (ifr))
					break;
				error = copyout((caddr_t)&ifr, (caddr_t)ifrp,
						sizeof (ifr.ifr_name));
				if (error == 0)
				    error = copyout((caddr_t)sa,
				      (caddr_t)&ifrp->ifr_addr, sa->sa_len);
				ifrp = (struct ifreq *)
					(sa->sa_len + (caddr_t)&ifrp->ifr_addr);
			}
			if (error)
				break;
			space -= sizeof (ifr);
		}
	}
	ifc->ifc_len -= space;
	return (error);
}

SYSCTL_NODE(_net, PF_LINK, link, CTLFLAG_RW, 0, "Link layers");
SYSCTL_NODE(_net_link, 0, generic, CTLFLAG_RW, 0, "Generic link-management");