In cases where tailscale is operating behind a MITM proxy, we need to consider
that a lot more of the internals of our HTTP requests are visible and may be
used as part of authorization checks. As such, we need to 'behave' as closely
as possible to ideal.
- Some proxies do authorization or consistency checks based the on Host header
or HTTP URI, instead of just the IP/hostname/SNI. As such, we need to
construct a `*http.Request` with a valid URI everytime HTTP is going to be
used on the wire, even if its over TLS.
Aside from the singular instance in net/netcheck, I couldn't find anywhere
else a http.Request was constructed incorrectly.
- Some proxies may deny requests, typically by returning a 403 status code. We
should not consider these requests as a valid latency check, so netcheck
semantics have been updated to consider >299 status codes as a failed probe.
Signed-off-by: Tom DNetto <tom@tailscale.com>
From the machines tab its hard to differenciate desktop Linux installs from
server Linux installs. Transmitting this information should make this
determination a lot easier.
Due to the reality that tailscaled is likely a system process, the standard
checks based on XDG_SESSION_TYPE or DISPLAY environment variables are not
possible (those variables won't be set). Instead, we look for listening
unix sockets that are typical of desktop installs.
Signed-off-by: Tom DNetto <tom@tailscale.com>
Updates #4377
Very smoky/high-level test to ensure that derphttp internals play well
with an agressive (stare + bump) meddler-in-the-middle proxy.
Signed-off-by: Tom DNetto <tom@tailscale.com>
I would like to do some more customized integration tests in the future,
(specifically, bringing up a mitm proxy and testing tailscaled through that)
so hoping to bring back the nixos wiring to support that.
Signed-off-by: Tom DNetto <tom@tailscale.com>
This change builds a derivation for tailscale-go and makes it available in the
users development environment. This is consistent with the shell.nix in corp/.
Once go1.18 is in a stable Nixpkgs release we can avoid relying on derivations
from nixpkgs head. For now, this works well, and the fetched derivations are
cached in the Nix store according to the usual rules.
Fixes#4231
Signed-off-by: Tom DNetto <tom@tailscale.com>
Tom DNettoandTom
