android: honor user-installed CA certificates for DERP servers#812
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pks-t wants to merge 1 commit into
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android: honor user-installed CA certificates for DERP servers#812pks-t wants to merge 1 commit into
pks-t wants to merge 1 commit into
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In e7fca1a (libtailscale,android: use ExtraRootCAs for user-installed CA certificates, 2026-04-08), we added the ability to honor user-installed CA certificates. This allows the user to connect to a Headscale server that uses a self-signed certificate. While this works for connecting to the server itself, this new feature is broken in case any of the DERP servers contained in the DERP map use self-signed certificates, too. This is because we set up the cert pool for `sys.ExtraRootCAs`, but not for `wgengine.Config`. The latter though is what we use to configure the DERP client, and consequently the TLS dialer doesn't respect any user-installed CA certificates. Fix this by propagating the cert pool via `wgengine.Config`. Signed-off-by: Patrick Steinhardt <ps@pks.im>
bradfitz
approved these changes
Jun 21, 2026
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In e7fca1a (libtailscale,android: use ExtraRootCAs for user-installed CA certificates, 2026-04-08), we added the ability to honor user-installed CA certificates. This allows the user to connect to a Headscale server that uses a self-signed certificate.
While this works for connecting to the server itself, this new feature is broken in case any of the DERP servers contained in the DERP map use self-signed certificates, too. This is because we set up the cert pool for
sys.ExtraRootCAs, but not forwgengine.Config. The latter though is what we use to configure the DERP client, and consequently the TLS dialer doesn't respect any user-installed CA certificates.Fix this by propagating the cert pool via
wgengine.Config.