The controlhttp dialer with a ControlDialPlan IPv6 entry was hitting a
case where the dnscache Resolver was returning an netip.Addr zero
value, where it should've been returning the IPv6 address.
We then tried to dial "invalid IP:80", which would immediately fail,
at least locally.
Mostly this was causing spammy logs when debugging other stuff.
Updates tailscale/corp#32534
Change-Id: If8b9a20f10c1a6aa8a662c324151d987fe9bd2f8
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
We have many function pointers that we replace for the duration of test and
restore it on test completion, add method to do that.
Signed-off-by: Maisem Ali <maisem@tailscale.com>
Now that we're using rand.Shuffle in a few locations, create a generic
shuffle function and use it instead. While we're at it, move the
interleaveSlices function to the same package for use.
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I0b00920e5b3eea846b6cedc30bd34d978a049fd3
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>
This allows users to temporarily enable/disable dnscache logging via a
new node capability, to aid in debugging strange connectivity issues.
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I46cf2596a8ae4c1913880a78d0033f8b668edc08
Simplify the ability to reason about the DoH dialing code by reusing the
dnscache's dialer we already have.
Also, reduce the scope of the "ip" variable we don't want to close over.
This necessarily adds a new field to dnscache.Resolver:
SingleHostStaticResult, for when the caller already knows the IPs to be
returned.
Change-Id: I9f2aef7926f649137a5a3e63eebad6a3fffa48c0
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
If we've already connected to a certain name's IP in the past, don't
assume the problem was DNS related. That just puts unnecessarily load
on our bootstrap DNS servers during regular restarts of Tailscale
infrastructure components.
Also, if we do do a bootstrap DNS lookup and it gives the same IP(s)
that we already tried, don't try them again.
Change-Id: I743e8991a7f957381b8e4c1508b8e9d0df1782fe
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Tested manually with:
$ go test -v ./net/dnscache/ -dial-test=bogusplane.dev.tailscale.com:80
Where bogusplane has three A records, only one of which works.
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
