Our current workaround made the user check too lax, thus allowing deleted
users. This patch adds a helper function to winutil that checks that the
uid's SID represents a valid Windows security principal.
Now if `lookupUserFromID` determines that the SID is invalid, we simply
propagate the error.
Updates https://github.com/tailscale/tailscale/issues/869
Signed-off-by: Aaron Klotz <aaron@tailscale.com>
utils/winutil/vss contains just enough COM wrapping to query the Volume Shadow Copy service for snapshots.
WalkSnapshotsForLegacyStateDir is the friendlier interface that adds awareness of our actual use case,
mapping the snapshots and locating our legacy state directory.
Updates #3011
Signed-off-by: Aaron Klotz <aaron@tailscale.com>
This helper allows us to retrieve `DWORD` and `QWORD` values from the Tailscale key in the Windows registry.
Signed-off-by: Aaron Klotz <aaron@tailscale.com>
Aaron Klotz
Josh Bleecher Snyder
David Crawshaw
Christine Dodrill
Brad Fitzpatrick