My earlier 3fa58303d0 tried to implement
the net/http.Tranhsport.DialTLSContext hook, but I didn't return a
*tls.Conn, so we ended up sending a plaintext HTTP request to an HTTPS
port. The response ended up being Go telling as such, not the
/derp/latency-check handler's response (which is currently still a
404). But we didn't even get the 404.
This happened to work well enough because Go's built-in error response
was still a valid HTTP response that we can measure for timing
purposes, but it's not a great answer. Notably, it means we wouldn't
be able to get a future handler to run server-side and count those
latency requests.
Also:
* add -verbose flag to cmd/tailscale netcheck
* remove some API from the interfaces package
* convert some of the interfaces package to netaddr.IP
* don't even send IPv4 probes on machines with no IPv4 (or only v4
loopback)
* and once three regions have replied, stop waiting for other probes
at 2x the slowest duration.
Updates #376
Under some conditions, code would try to look things up in the maps
before the first call to updateLatency. I don't see any reason to delay
initialization of the maps, so let's just init them right away when
creating the Report instance.
Signed-off-by: Avery Pennarun <apenwarr@tailscale.com>
