The netcheck client, when no UDP is available, probes distance using
HTTPS.
Several problems:
* It probes using /derp/latency-check.
* But cmd/derper serves the handler at /derp/probe
* Despite the difference, it work by accident until c8f4dfc8c0
which made netcheck's probe require a 2xx status code.
* in tests, we only use derphttp.Handler, so the cmd/derper-installed
mux routes aren't preesnt, so there's no probe. That breaks
tests in airplane mode. netcheck.Client then reports "unexpected
HTTP status 426" (Upgrade Required)
This makes derp handle both /derp/probe and /derp/latency-check
equivalently, and in both cmd/derper and derphttp.Handler standalone
modes.
I notice this when wgengine/magicsock TestActiveDiscovery was failing
in airplane mode (no wifi). It still doesn't pass, but it gets
further.
Fixes#11989
Change-Id: I45213d4bd137e0f29aac8bd4a9ac92091065113f
This updates all source files to use a new standard header for copyright
and license declaration. Notably, copyright no longer includes a date,
and we now use the standard SPDX-License-Identifier header.
This commit was done almost entirely mechanically with perl, and then
some minimal manual fixes.
Updates #6865
Signed-off-by: Will Norris <will@tailscale.com>
Otherwise random browser requests to /derp cause log spam.
Change-Id: I7bdf991d2106f0323868e651156c788a877a90d5
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
* advertise server's DERP public key following its ServerHello
* have client look for that DEPR public key in the response
PeerCertificates
* let client advertise it's going into a "fast start" mode
if it finds it
* modify server to support that fast start mode, just not
sending the HTTP response header
Cuts down another round trip, bringing the latency of being able to
write our first DERP frame from SF to Bangalore from ~725ms
(3 RTT) to ~481ms (2 RTT: TCP and TLS).
Fixes#693
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
