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| author | Brad Fitzpatrick <bradfitz@tailscale.com> | 2025-09-29 22:10:28 -0700 |
|---|---|---|
| committer | Brad Fitzpatrick <brad@danga.com> | 2025-09-30 08:25:24 -0700 |
| commit | bcd79b161acbf90dfcfe71cbde847a320a41b7fe (patch) | |
| tree | d9acf006fd800c31a77c56531631f2bbb2b11fa8 /control/controlclient | |
| parent | a45473c4c58832073761c4619d1c912e2a49c7fa (diff) | |
| download | tailscale-bcd79b161acbf90dfcfe71cbde847a320a41b7fe.tar.xz tailscale-bcd79b161acbf90dfcfe71cbde847a320a41b7fe.zip | |
feature/featuretags: add option to turn off DNS
Saves 328 KB (2.5%) off the minimal binary.
For IoT devices that don't need MagicDNS (e.g. they don't make
outbound connections), this provides a knob to disable all the DNS
functionality.
Rather than a massive refactor today, this uses constant false values
as a deadcode sledgehammer, guided by shotizam to find the largest DNS
functions which survived deadcode.
A future refactor could make it so that the net/dns/resolver and
publicdns packages don't even show up in the import graph (along with
their imports) but really it's already pretty good looking with just
these consts, so it's not at the top of my list to refactor it more
soon.
Also do the same in a few places with the ACME (cert) functionality,
as I saw those while searching for DNS stuff.
Updates #12614
Change-Id: I8e459f595c2fde68ca16503ff61c8ab339871f97
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Diffstat (limited to 'control/controlclient')
| -rw-r--r-- | control/controlclient/direct.go | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/control/controlclient/direct.go b/control/controlclient/direct.go index 6d18e306f..31f41eac8 100644 --- a/control/controlclient/direct.go +++ b/control/controlclient/direct.go @@ -30,6 +30,7 @@ import ( "tailscale.com/control/controlknobs" "tailscale.com/envknob" "tailscale.com/feature" + "tailscale.com/feature/buildfeatures" "tailscale.com/health" "tailscale.com/hostinfo" "tailscale.com/ipn/ipnstate" @@ -1580,6 +1581,9 @@ func (c *Direct) setDNSNoise(ctx context.Context, req *tailcfg.SetDNSRequest) er // SetDNS sends the SetDNSRequest request to the control plane server, // requesting a DNS record be created or updated. func (c *Direct) SetDNS(ctx context.Context, req *tailcfg.SetDNSRequest) (err error) { + if !buildfeatures.HasACME { + return feature.ErrUnavailable + } metricSetDNS.Add(1) defer func() { if err != nil { |