Peter Steele wrote:
... I personally like this idea, but I'm not sure I can sell it to the others. Are there any restrictions to these 169.254.x.y addresses?
169.254.0.0/16 must never appear outside a link -- it is strictly scoped to that link.
Currently the IPv4 BSD stack has no concept of link-scoped addresses, but IPv6 does. Link is a realized concept there because of KAME's support for the %<ifname> syntax. Internally, interface indexes get used.
In practice this shouldn't be an issue as long as you can guarantee different addresses are used for the 169.254.0.0/16 block on each interface, however, it would mean any app using sockets would need to explicitly bind to the local address to ensure the correct interface is used. Furthermore, we effectively need to be able to support multiple next-hops for the 169.254.0.0/16 prefix, otherwise we can support only one such interface w/o significant kernel code rewrites.
So, really, LL may not buy you anything at all, and it's likely you need to go straight to pcap for your app. These restrictions have existed for years, and the fact that they haven't been addressed has largely been because there has been no community strategy to deal with it. I speculate some BSD-using organisations might have already solved these problems, however, without evidence (and code sharing), that's pure speculation.
cheers BMS _______________________________________________ freebsd-net@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-net To unsubscribe, send any mail to "freebsd-net-unsubscr...@freebsd.org"
