Only accept an address from a peer if it is a valid IP address

[matthew1001]

PR description

When using the From address specified by a peer, ensure it is a valid IP address. Otherwise revert to using the UDP source host.

Fixed Issue(s)

See comment #6225 (comment)

[github-actions]

• I thought about documentation and added the doc-change-required label to this PR if updates are required.
• I thought about the changelog and included a changelog update if required.
• If my PR includes database changes (e.g. KeyValueSegmentIdentifier) I have thought about compatibility and performed forwards and backwards compatibility tests

[matkt]

LGTM

[matthew1001]

I'll submit another PR to honour DNS names DNS peering is enabled for the node, but it would be good to just get this fix in first.

[garyschulte]

it looks like we need to add 255.255.255.255 to this filter. on mainnet we are regularly seeing logs like:

{"@timestamp":"2024-01-24T06:18:16,129","level":"WARN","thread":"vert.x-eventloop-thread-3","class":"VertxPeerDiscoveryAgent","message":"Sending to peer DiscoveryPeer{status=bonding, enode=enode://5d01e72875f3485fdcce5255720696087ea7d704c6632282fbe39329db6417a6f5ef940cf05519677be7f9c31b6b553fe9192e9e9feed37db3fb97bcc7fd099e@255.255.255.255:30313, firstDiscovered=1706077069751, lastContacted=0, lastSeen=1706077069751} failed, native error code -13, packet: 0x3123aed37feabe25bd4cc2625a1d1e2b12a5a1bbe6f3ef594c1ea76abbfbae670ab30477655186a5a3bf4487f2fa183807dad26037e950e89cc07ba20eaf229437e69c2e56d44fe934082147098ca4a0bd99964d67d2046789d080f69d5be2c60101df05cb8489757c7882765f82765fcb84ffffffff8276698276698465b0abe402, stacktrace: io.netty.channel.unix.Errors$NativeIoException: sendToAddress(..) failed: Permission denied","throwable":""}

[garyschulte]

A more robust solution would be to filter by reachable addresses

[matthew1001]

Could possibly do both - specifically exclude 255.255.255.255 and also apply a InetAddress.isReachable() check?

[matthew1001]

I'll look at raising a PR that at least adds 255.255.255.255 to the exclude list, possibly with some refactoring of the filter predicate now that it's becoming more complicated.