Fix IPv6 packets receiving

[NN (NN---)]

For some reason IPPROTO_IP6 doens't work.

When I replace IPPROTO_IPV6 with IPPROTO_IP do see traffic coming to the socket but unfortunately it doesn't include the IPv6 header. I tried setting the IP_HDRINCL socket option: int on = 1; setsockopt(fd, IPPROTO_IP, IP_HDRINCL, &on, sizeof(on)); and also setting IPV6_HDRINCL: int on = 1; setsockopt(fd, IPPROTO_IPV6, IPV6_HDRINCL, &on, sizeof(on)); but none of them help. Any ideas? – seladb Sep 7 '18 at 15:32

https://stackoverflow.com/questions/52218511/windows-ipv6-raw-sockets-why-dont-i-see-incoming-packets

[rilysh]

Instead of removing IPPROTO_IPV6, you may create a fallback, like

if (resif->ai_family == AF_INET)
        g_dwProtocol = IPPROTO_IP;
else if (resif->ai_family == AF_INET6)
        g_dwProtocol = IPPROTO_IPV6;
else
        g_dwProtocol = IPPROTO_IP;

Though I haven't locally tested yet.