diff options
| -rw-r--r-- | sys/net/if_tap.c | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/sys/net/if_tap.c b/sys/net/if_tap.c index 1b51647..653d618 100644 --- a/sys/net/if_tap.c +++ b/sys/net/if_tap.c @@ -813,6 +813,7 @@ tapread(struct cdev *dev, struct uio *uio, int flag) static int tapwrite(struct cdev *dev, struct uio *uio, int flag) { + struct ether_header *eh; struct tap_softc *tp = dev->si_drv1; struct ifnet *ifp = tp->tap_ifp; struct mbuf *m; @@ -838,6 +839,23 @@ tapwrite(struct cdev *dev, struct uio *uio, int flag) m->m_pkthdr.rcvif = ifp; + /* + * Only pass a unicast frame to ether_input(), if it would actually + * have been received by non-virtual hardware. + */ + if (m->m_len < sizeof(struct ether_header)) { + m_freem(m); + return (0); + } + eh = mtod(m, struct ether_header *); + + if (eh && (ifp->if_flags & IFF_PROMISC) == 0 && + !ETHER_IS_MULTICAST(eh->ether_dhost) && + bcmp(eh->ether_dhost, IF_LLADDR(ifp), ETHER_ADDR_LEN) != 0) { + m_freem(m); + return (0); + } + /* Pass packet up to parent. */ (*ifp->if_input)(ifp, m); ifp->if_ipackets ++; /* ibytes are counted in parent */ |
