DP-3T / dp3t-sdk-backend

The backend implementation for DP3T
Mozilla Public License 2.0
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valid delayedKeys might be rejected #238

Open ineiti opened 4 years ago

ineiti commented 4 years ago

Probably not important anymore, as delayed keys will get more and more rare with the new GAEN versions. But the following can happen with very unfortunate clock synchronisation:

  1. Day 1: User sends keys to exposed with a delayedKeyDate from day 0, which is accepted by ValidationUtils.validateDelayedKeyDate, and a JWT token created
  2. Day 2: User sends last key to exposednextday with the key from day 0, which matches the JWT claim created by exposed, but which will be rejected by ValidationUtils.vlidateDelayedKeyDate