Flip the QAP! Witness Encryption for DCAP

The long form writeup is at https://heytdep.github.io/post/43/post.html, but here I would like to spark discussion for potential use cases for this construct. TLDR; I embed DCAP verification in a circom circuit, then use WKEM scheme to encrypt a payload to a key so that only a decryptor with valid witnesses for the circuit can derive such key.

First use cases that come to my mind (will post more as I think thorugh them):

  • non interactive encrypted state persistance. any valid tee (that doesn’t necessarily need to exist at the time of encryption/perform any handshake with encryptor) can decrypt state. perfect for system-wide crashes.
  • non interactive indirect P2P comms through a confidential broker (wide use cases confiined here tbh).

what else?