* Improve map auth logic
* Bugfix
* Add comment, improve error message
* noise: make func, get by node
this commit splits the additional validation into a
separate function so it can be reused if we add more
endpoints in the future.
It swaps the check, so we still look up by NodeKey, but before
accepting the connection, we validate the known machinekey from
the db against the noise connection.
The reason for this is that when a node logs in or out, the node key
is replaced and it will no longer be possible to look it up, breaking
reauthentication.
Signed-off-by: Kristoffer Dalby <kristoffer@tailscale.com>
Co-authored-by: Kristoffer Dalby <kristoffer@tailscale.com>
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