shadowsocks-libev-ss-rules blocks UDP/IPv6 multicast including DHCPv6

[yaleh]

Maintainer: Yousong Zhou yszhou4tech@gmail.com
Environment: (OpenWrt 22.03.0 r19685-512e76967f / LuCI openwrt-22.03 branch git-22.245.77528-487e58a)

Description:

shadowsocks-libev-ss-rules bypassed some preserved IPv6 addresses, but missed IPv6 multicast addresses. So, all IPv6 multicast packets are redirected to Shadowsocks once it's enabled.

It's suggested to add IPv6 multicast address ff00::/8 to /usr/share/ss-rules/set.uc:

let o_dst_bypass6_ = "
        ::1/128
        ::/128
        ::ffff:0:0/96
        64:ff9b:1::/48
        100::/64
        fe80::/10
        2001::/23
        fc00::/7
";