in.c

eCos操作系统源码

 *	SIOCGLIFADDR with IFLR_PREFIX:
 *		get first address that matches the specified prefix.
 *	SIOCALIFADDR: add the specified address.
 *	SIOCALIFADDR with IFLR_PREFIX:
 *		EINVAL since we can't deduce hostid part of the address.
 *	SIOCDLIFADDR: delete the specified address.
 *	SIOCDLIFADDR with IFLR_PREFIX:
 *		delete the first address that matches the specified prefix.
 * return values:
 *	EINVAL on invalid parameters
 *	EADDRNOTAVAIL on prefix match failed/specified address not found
 *	other values may be returned from in_ioctl()
 */
static int
in_lifaddr_ioctl(so, cmd, data, ifp)
	struct socket *so;
	u_long cmd;
	caddr_t	data;
	struct ifnet *ifp;
{
	struct if_laddrreq *iflr = (struct if_laddrreq *)data;
	struct ifaddr *ifa;
	struct sockaddr *sa;

	/* sanity checks */
	if (!data || !ifp) {
		panic("invalid argument to in_lifaddr_ioctl");
		/*NOTRECHED*/
	}

	switch (cmd) {
	case SIOCGLIFADDR:
		/* address must be specified on GET with IFLR_PREFIX */
		if ((iflr->flags & IFLR_PREFIX) == 0)
			break;
		/*FALLTHROUGH*/
	case SIOCALIFADDR:
	case SIOCDLIFADDR:
		/* address must be specified on ADD and DELETE */
		sa = (struct sockaddr *)&iflr->addr;
		if (sa->sa_family != AF_INET)
			return EINVAL;
		if (sa->sa_len != sizeof(struct sockaddr_in))
			return EINVAL;
		/* XXX need improvement */
		sa = (struct sockaddr *)&iflr->dstaddr;
		if (sa->sa_family
		 && sa->sa_family != AF_INET)
			return EINVAL;
		if (sa->sa_len && sa->sa_len != sizeof(struct sockaddr_in))
			return EINVAL;
		break;
	default: /*shouldn't happen*/
#if 0
		panic("invalid cmd to in_lifaddr_ioctl");
		/*NOTREACHED*/
#else
		return EOPNOTSUPP;
#endif
	}
	if (sizeof(struct in_addr) * 8 < iflr->prefixlen)
		return EINVAL;

	switch (cmd) {
	case SIOCALIFADDR:
	    {
		struct in_aliasreq ifra;

		if (iflr->flags & IFLR_PREFIX)
			return EINVAL;

		/* copy args to in_aliasreq, perform ioctl(SIOCAIFADDR_IN6). */
		bzero(&ifra, sizeof(ifra));
		bcopy(iflr->iflr_name, ifra.ifra_name,
			sizeof(ifra.ifra_name));

		bcopy(&iflr->addr, &ifra.ifra_addr,
			((struct sockaddr *)&iflr->addr)->sa_len);

		if (((struct sockaddr *)&iflr->dstaddr)->sa_family) {	/*XXX*/
			bcopy(&iflr->dstaddr, &ifra.ifra_dstaddr,
				((struct sockaddr *)&iflr->dstaddr)->sa_len);
		}

		ifra.ifra_mask.sin_family = AF_INET;
		ifra.ifra_mask.sin_len = sizeof(struct sockaddr_in);
		in_len2mask(&ifra.ifra_mask.sin_addr, iflr->prefixlen);

		return in_control(so, SIOCAIFADDR, (caddr_t)&ifra, ifp);
	    }
	case SIOCGLIFADDR:
	case SIOCDLIFADDR:
	    {
		struct in_ifaddr *ia;
		struct in_addr mask, candidate, match;
		struct sockaddr_in *sin;
		int cmp;

		bzero(&mask, sizeof(mask));
		if (iflr->flags & IFLR_PREFIX) {
			/* lookup a prefix rather than address. */
			in_len2mask(&mask, iflr->prefixlen);

			sin = (struct sockaddr_in *)&iflr->addr;
			match.s_addr = sin->sin_addr.s_addr;
			match.s_addr &= mask.s_addr;

			/* if you set extra bits, that's wrong */
			if (match.s_addr != sin->sin_addr.s_addr)
				return EINVAL;

			cmp = 1;
		} else {
			if (cmd == SIOCGLIFADDR) {
				/* on getting an address, take the 1st match */
				cmp = 0;	/*XXX*/
			} else {
				/* on deleting an address, do exact match */
				in_len2mask(&mask, 32);
				sin = (struct sockaddr_in *)&iflr->addr;
				match.s_addr = sin->sin_addr.s_addr;

				cmp = 1;
			}
		}

		for (ifa = ifp->if_addrlist.tqh_first; ifa; ifa = ifa->ifa_list.tqe_next) {
			if (ifa->ifa_addr->sa_family != AF_INET6)
				continue;
			if (!cmp)
				break;
			candidate.s_addr = ((struct sockaddr_in *)&ifa->ifa_addr)->sin_addr.s_addr;
			candidate.s_addr &= mask.s_addr;
			if (candidate.s_addr == match.s_addr)
				break;
		}
		if (!ifa)
			return EADDRNOTAVAIL;
		ia = (struct in_ifaddr *)ifa;

		if (cmd == SIOCGLIFADDR) {
			/* fill in the if_laddrreq structure */
			bcopy(&ia->ia_addr, &iflr->addr, ia->ia_addr.sin_len);

			if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
				bcopy(&ia->ia_dstaddr, &iflr->dstaddr,
					ia->ia_dstaddr.sin_len);
			} else
				bzero(&iflr->dstaddr, sizeof(iflr->dstaddr));

			iflr->prefixlen =
				in_mask2len(&ia->ia_sockmask.sin_addr);

			iflr->flags = 0;	/*XXX*/

			return 0;
		} else {
			struct in_aliasreq ifra;

			/* fill in_aliasreq and do ioctl(SIOCDIFADDR_IN6) */
			bzero(&ifra, sizeof(ifra));
			bcopy(iflr->iflr_name, ifra.ifra_name,
				sizeof(ifra.ifra_name));

			bcopy(&ia->ia_addr, &ifra.ifra_addr,
				ia->ia_addr.sin_len);
			if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
				bcopy(&ia->ia_dstaddr, &ifra.ifra_dstaddr,
					ia->ia_dstaddr.sin_len);
			}
			bcopy(&ia->ia_sockmask, &ifra.ifra_dstaddr,
				ia->ia_sockmask.sin_len);

			return in_control(so, SIOCDIFADDR, (caddr_t)&ifra, ifp);
		}
	    }
	}

	return EOPNOTSUPP;	/*just for safety*/
}

/*
 * Delete any existing route for an interface.
 */
void
in_ifscrub(ifp, ia)
	register struct ifnet *ifp;
	register struct in_ifaddr *ia;
{

	if ((ia->ia_flags & IFA_ROUTE) == 0)
		return;
	if (ifp->if_flags & (IFF_LOOPBACK|IFF_POINTOPOINT))
		rtinit(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST);
	else
		rtinit(&(ia->ia_ifa), (int)RTM_DELETE, 0);
	ia->ia_flags &= ~IFA_ROUTE;
}

/*
 * Initialize an interface's internet address
 * and routing table entry.
 */
int
in_ifinit(ifp, ia, sin, scrub)
	register struct ifnet *ifp;
	register struct in_ifaddr *ia;
	struct sockaddr_in *sin;
	int scrub;
{
	register u_int32_t i = sin->sin_addr.s_addr;
	struct sockaddr_in oldaddr;
	int s = splimp(), flags = RTF_UP, error;

	oldaddr = ia->ia_addr;
	ia->ia_addr = *sin;
	/*
	 * Give the interface a chance to initialize
	 * if this is its first address,
	 * and to validate the address if necessary.
	 */
	if (ifp->if_ioctl &&
	    (error = (*ifp->if_ioctl)(ifp, SIOCSIFADDR, (caddr_t)ia))) {
		splx(s);
		ia->ia_addr = oldaddr;
		return (error);
	}
	splx(s);
	if (scrub) {
		ia->ia_ifa.ifa_addr = sintosa(&oldaddr);
		in_ifscrub(ifp, ia);
		ia->ia_ifa.ifa_addr = sintosa(&ia->ia_addr);
	}
	if (IN_CLASSA(i))
		ia->ia_netmask = IN_CLASSA_NET;
	else if (IN_CLASSB(i))
		ia->ia_netmask = IN_CLASSB_NET;
	else
		ia->ia_netmask = IN_CLASSC_NET;
	/*
	 * The subnet mask usually includes at least the standard network part,
	 * but may may be smaller in the case of supernetting.
	 * If it is set, we believe it.
	 */
	if (ia->ia_subnetmask == 0) {
		ia->ia_subnetmask = ia->ia_netmask;
		ia->ia_sockmask.sin_addr.s_addr = ia->ia_subnetmask;
	} else
		ia->ia_netmask &= ia->ia_subnetmask;
	ia->ia_net = i & ia->ia_netmask;
	ia->ia_subnet = i & ia->ia_subnetmask;
	in_socktrim(&ia->ia_sockmask);
	/*
	 * Add route for the network.
	 */
	ia->ia_ifa.ifa_metric = ifp->if_metric;
	if (ifp->if_flags & IFF_BROADCAST) {
		ia->ia_broadaddr.sin_addr.s_addr =
			ia->ia_subnet | ~ia->ia_subnetmask;
		ia->ia_netbroadcast.s_addr =
			ia->ia_net | ~ia->ia_netmask;
	} else if (ifp->if_flags & IFF_LOOPBACK) {
		ia->ia_ifa.ifa_dstaddr = ia->ia_ifa.ifa_addr;
		flags |= RTF_HOST;
	} else if (ifp->if_flags & IFF_POINTOPOINT) {
		if (ia->ia_dstaddr.sin_family != AF_INET)
			return (0);
		flags |= RTF_HOST;
	}
	if ((error = rtinit(&(ia->ia_ifa), (int)RTM_ADD, flags)) == 0)
		ia->ia_flags |= IFA_ROUTE;
	/*
	 * If the interface supports multicast, join the "all hosts"
	 * multicast group on that interface.
	 */
	if (ifp->if_flags & IFF_MULTICAST) {
		struct in_addr addr;

		addr.s_addr = INADDR_ALLHOSTS_GROUP;
		in_addmulti(&addr, ifp);
	}
	return (error);
}


/*
 * Return 1 if the address might be a local broadcast address.
 */
int
in_broadcast(in, ifp)
	struct in_addr in;
	struct ifnet *ifp;
{
	struct ifnet *ifn, *if_first, *if_target;
	register struct ifaddr *ifa;

	if (in.s_addr == INADDR_BROADCAST ||
	    in.s_addr == INADDR_ANY)
		return 1;
	if (ifp && ((ifp->if_flags & IFF_BROADCAST) == 0))
		return 0;

	if (ifp == NULL)
	{
	  	if_first = ifnet.tqh_first;
		if_target = 0;
	}
	else
	{
		if_first = ifp;
		if_target = ifp->if_list.tqe_next;
	}

#define ia (ifatoia(ifa))
	/*
	 * Look through the list of addresses for a match
	 * with a broadcast address.
	 * If ifp is NULL, check against all the interfaces.
	 */
        for (ifn = if_first; ifn != if_target; ifn = ifn->if_list.tqe_next)
	  for (ifa = ifn->if_addrlist.tqh_first; ifa;
	       ifa = ifa->ifa_list.tqe_next)
	      if (!ifp)
	      {
		  if (ifa->ifa_addr->sa_family == AF_INET &&
		      ((ia->ia_subnetmask != 0xffffffff &&
		      (((ifn->if_flags & IFF_BROADCAST) &&
			in.s_addr == ia->ia_broadaddr.sin_addr.s_addr) ||
			 in.s_addr == ia->ia_subnet)) ||
		       /*
			* Check for old-style (host 0) broadcast.
			*/
		       (in.s_addr == ia->ia_netbroadcast.s_addr ||
			in.s_addr == ia->ia_net)))
		              return 1;
	      }
	      else
		  if (ifa->ifa_addr->sa_family == AF_INET &&
		      (((ifn->if_flags & IFF_BROADCAST) &&
		      in.s_addr == ia->ia_broadaddr.sin_addr.s_addr) ||
		       in.s_addr == ia->ia_netbroadcast.s_addr ||
		       /*
			* Check for old-style (host 0) broadcast.
			*/
		       in.s_addr == ia->ia_subnet ||
		       in.s_addr == ia->ia_net))
		              return 1;
	return (0);
#undef ia
}

/*
 * Add an address to the list of IP multicast addresses for a given interface.
 */
struct in_multi *
in_addmulti(ap, ifp)
	register struct in_addr *ap;
	register struct ifnet *ifp;
{
	register struct in_multi *inm;
	struct ifreq ifr;
	struct in_ifaddr *ia;
	int s = splsoftnet();

	/*
	 * See if address already in list.
	 */
	IN_LOOKUP_MULTI(*ap, ifp, inm);
	if (inm != NULL) {
		/*
		 * Found it; just increment the reference count.
		 */
		++inm->inm_refcount;
	} else {
		/*
		 * New address; allocate a new multicast record
		 * and link it into the interface's multicast list.
		 */
		inm = (struct in_multi *)malloc(sizeof(*inm),
		    M_IPMADDR, M_NOWAIT);
		if (inm == NULL) {
			splx(s);
			return (NULL);
		}
		inm->inm_addr = *ap;
		inm->inm_ifp = ifp;
		inm->inm_refcount = 1;
		IFP_TO_IA(ifp, ia);
		if (ia == NULL) {
			free(inm, M_IPMADDR);
			splx(s);
			return (NULL);
		}
		inm->inm_ia = ia;
		LIST_INSERT_HEAD(&ia->ia_multiaddrs, inm, inm_list);
		/*
		 * Ask the network driver to update its multicast reception
		 * filter appropriately for the new address.
		 */
		satosin(&ifr.ifr_addr)->sin_len = sizeof(struct sockaddr_in);
		satosin(&ifr.ifr_addr)->sin_family = AF_INET;
		satosin(&ifr.ifr_addr)->sin_addr = *ap;
		if ((ifp->if_ioctl == NULL) ||
		    (*ifp->if_ioctl)(ifp, SIOCADDMULTI,(caddr_t)&ifr) != 0) {
			LIST_REMOVE(inm, inm_list);
			free(inm, M_IPMADDR);
			splx(s);
			return (NULL);
		}
		/*
		 * Let IGMP know that we have joined a new IP multicast group.
		 */
		igmp_joingroup(inm);
	}
	splx(s);
	return (inm);
}

/*
 * Delete a multicast address record.
 */
void
in_delmulti(inm)
	register struct in_multi *inm;
{
	struct ifreq ifr;
	int s = splsoftnet();

	if (--inm->inm_refcount == 0) {
		/*
		 * No remaining claims to this record; let IGMP know that
		 * we are leaving the multicast group.
		 */
		igmp_leavegroup(inm);
		/*
		 * Unlink from list.
		 */
		LIST_REMOVE(inm, inm_list);
		/*
		 * Notify the network driver to update its multicast reception
		 * filter.
		 */
		satosin(&ifr.ifr_addr)->sin_family = AF_INET;
		satosin(&ifr.ifr_addr)->sin_addr = inm->inm_addr;
		(*inm->inm_ifp->if_ioctl)(inm->inm_ifp, SIOCDELMULTI,
							     (caddr_t)&ifr);
		free(inm, M_IPMADDR);
	}
	splx(s);
}

#endif