• Andre Naujoks's avatar
    ipv6: Add sockopt IPV6_MULTICAST_ALL analogue to IP_MULTICAST_ALL · 15033f04
    Andre Naujoks authored
    The socket option will be enabled by default to ensure current behaviour
    is not changed. This is the same for the IPv4 version.
    
    A socket bound to in6addr_any and a specific port will receive all traffic
    on that port. Analogue to IP_MULTICAST_ALL, disable this behaviour, if
    one or more multicast groups were joined (using said socket) and only
    pass on multicast traffic from groups, which were explicitly joined via
    this socket.
    
    Without this option disabled a socket (system even) joined to multiple
    multicast groups is very hard to get right. Filtering by destination
    address has to take place in user space to avoid receiving multicast
    traffic from other multicast groups, which might have traffic on the same
    port.
    
    The extension of the IP_MULTICAST_ALL socketoption to just apply to ipv6,
    too, is not done to avoid changing the behaviour of current applications.
    Signed-off-by: default avatarAndre Naujoks <nautsch2@gmail.com>
    Acked-By: default avatarYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
    15033f04
ipv6.h 8.93 KB