77bc49858c
an explicit action for INET6 configuration happens. The changes are: 1. When an ND6 flag is changed via SIOCSIFINFO_FLAGS ioctl, setting ND6_IFF_ACCEPT_RTADV and/or ND6_IFF_AUTO_LINKLOCAL now triggers an attempt to clear the ND6_IFF_IFDISABLED flag. 2. When an AF_INET6 address is added successfully to an interface and it is marked as ND6_IFF_IFDISABLED, an attempt to clear the ND6_IFF_IFDISABLED happens. This simplifies ND6_IFF_IFDISABLED flag manipulation by users via ifconfig(8); in most cases manual configuration is no longer needed. - When ND6_IFF_AUTO_LINKLOCAL is set and no link-local address is assigned to an interface, SIOCSIFINFO_FLAGS ioctl now calls in6_ifattach() to configure a link-local address. This change ensures link-local address configuration when "ifconfig IF inet6" command is invoked. For example, "ifconfig IF inet6 auto_linklocal" now always try to configure an LL addr even if ND6_IFF_AUTO_LINKLOCAL is already set to 1 (i.e. down/up cycle is no longer needed). Reviewed by: bz