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< * $Id: if.c,v 1.37 1996/12/11 20:38:14 wollman Exp $
---
> * $Id: if.c,v 1.38 1996/12/13 21:28:37 wollman Exp $
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> LIST_INIT(&ifp->if_multiaddrs);
760a762,938
> /*
> * Just like if_promisc(), but for all-multicast-reception mode.
> */
> int
> if_allmulti(ifp, onswitch)
> struct ifnet *ifp;
> int onswitch;
> {
> int error = 0;
> int s = splimp();
>
> if (onswitch) {
> if (ifp->if_amcount++ == 0) {
> ifp->if_flags |= IFF_ALLMULTI;
> error = ifp->if_ioctl(ifp, SIOCSIFFLAGS, 0);
> }
> } else {
> if (ifp->if_amcount > 1) {
> ifp->if_amcount--;
> } else {
> ifp->if_amcount = 0;
> ifp->if_flags &= ~IFF_ALLMULTI;
> error = ifp->if_ioctl(ifp, SIOCSIFFLAGS, 0);
> }
> }
> splx(s);
> return error;
> }
>
> /*
> * Add a multicast listenership to the interface in question.
> * The link layer provides a routine which converts
> */
> int
> if_addmulti(ifp, sa)
> struct ifnet *ifp; /* interface to manipulate */
> struct sockaddr *sa; /* address to add */
> {
> struct sockaddr *llsa, *dupsa;
> int error, s;
> struct ifmultiaddr *ifma;
>
> for (ifma = ifp->if_multiaddrs.lh_first; ifma;
> ifma = ifma->ifma_link.le_next) {
> if (equal(sa, ifma->ifma_addr))
> break;
> }
>
> if (ifma) {
> ifma->ifma_refcount++;
> return 0;
> }
>
> /*
> * Give the link layer a chance to accept/reject it, and also
> * find out which AF_LINK address this maps to, if it isn't one
> * already.
> */
> if (ifp->if_resolvemulti) {
> error = ifp->if_resolvemulti(ifp, &llsa, sa);
> if (error) return error;
> } else {
> llsa = 0;
> }
>
> MALLOC(ifma, struct ifmultiaddr *, sizeof *ifma, M_IFMADDR, M_WAITOK);
> MALLOC(dupsa, struct sockaddr *, sa->sa_len, M_IFMADDR, M_WAITOK);
> bcopy(sa, dupsa, sa->sa_len);
>
> ifma->ifma_addr = dupsa;
> ifma->ifma_lladdr = llsa;
> ifma->ifma_ifp = ifp;
> ifma->ifma_refcount = 1;
> /*
> * Some network interfaces can scan the address list at
> * interrupt time; lock them out.
> */
> s = splimp();
> LIST_INSERT_HEAD(&ifp->if_multiaddrs, ifma, ifma_link);
> splx(s);
>
> if (llsa != 0) {
> for (ifma = ifp->if_multiaddrs.lh_first; ifma;
> ifma = ifma->ifma_link.le_next) {
> if (equal(ifma->ifma_addr, llsa))
> break;
> }
> if (ifma) {
> ifma->ifma_refcount++;
> } else {
> MALLOC(ifma, struct ifmultiaddr *, sizeof *ifma,
> M_IFMADDR, M_WAITOK);
> ifma->ifma_addr = llsa;
> ifma->ifma_ifp = ifp;
> ifma->ifma_refcount = 1;
> }
> s = splimp();
> LIST_INSERT_HEAD(&ifp->if_multiaddrs, ifma, ifma_link);
> splx(s);
> }
> /*
> * We are certain we have added something, so call down to the
> * interface to let them know about it.
> */
> s = splimp();
> ifp->if_ioctl(ifp, SIOCADDMULTI, 0);
> splx(s);
>
> return 0;
> }
>
> /*
> * Remove a reference to a multicast address on this interface. Yell
> * if the request does not match an existing membership.
> */
> int
> if_delmulti(ifp, sa)
> struct ifnet *ifp;
> struct sockaddr *sa;
> {
> struct ifmultiaddr *ifma;
> int s;
>
> for (ifma = ifp->if_multiaddrs.lh_first; ifma;
> ifma = ifma->ifma_link.le_next)
> if (equal(sa, ifma->ifma_addr))
> break;
> if (ifma == 0)
> return ENOENT;
>
> if (ifma->ifma_refcount > 1) {
> ifma->ifma_refcount--;
> return 0;
> }
>
> sa = ifma->ifma_lladdr;
> s = splimp();
> LIST_REMOVE(ifma, ifma_link);
> splx(s);
> free(ifma->ifma_addr, M_IFMADDR);
> free(ifma, M_IFMADDR);
> if (sa == 0)
> return 0;
>
> /*
> * Now look for the link-layer address which corresponds to
> * this network address. It had been squirreled away in
> * ifma->ifma_lladdr for this purpose (so we don't have
> * to call ifp->if_resolvemulti() again), and we saved that
> * value in sa above. If some nasty deleted the
> * link-layer address out from underneath us, we can deal because
> * the address we stored was is not the same as the one which was
> * in the record for the link-layer address. (So we don't complain
> * in that case.)
> */
> for (ifma = ifp->if_multiaddrs.lh_first; ifma;
> ifma = ifma->ifma_link.le_next)
> if (equal(sa, ifma->ifma_addr))
> break;
> if (ifma == 0)
> return 0;
>
> if (ifma->ifma_refcount > 1) {
> ifma->ifma_refcount--;
> return 0;
> }
>
> s = splimp();
> LIST_REMOVE(ifma, ifma_link);
> splx(s);
> free(ifma->ifma_addr, M_IFMADDR);
> free(sa, M_IFMADDR);
> free(ifma, M_IFMADDR);
>
> return 0;
> }
>