Quickbeam Encryption flow

Note: This is not yet implemented!

Encrypt (Alice)

// input params $0 < t \leq |\mathcal{U}|$$m \in {0, 1}^$$R \in {0, 1}^$ an NP-Relation

// generate ciphertext and add to storage $(ek, ak) \leftarrow Preprocess(CRS, \mathcal{U}, \{hint_i, pk_i\}_{i \in [\mathcal{U}]})$ $ct \xleftarrow{R} STE.Enc(ek, m, t)$ $cid = Storage.Add(ct)$

// embedded intent $\bar{m} = \{(R, t), cid\}$ $\bar{cid} = Storage.Add(\bar{m})$

// register with intent storatge $filename \in \{0, 1\}^d$ $0/1 \leftarrow IntentStore.Register(filename, \bar{cid})$

Decrypt (Bob)

Assume Bob knows the filename of some encrypted data, $filename$.

// retrieve ciphertext loc, relation, and intent $\bar{cid} = IntentStore.Get(filename)$ $\{(R, t), cid\} = Storage.Get(\bar{cid})$

// this needs work... $S = DeriveStatement(R)$ Generate a witness $w$ s.t. $(w,s) \in R$

// collect partial decs $\{pd_1, ..., pd_k\}$ for some $k \geq t$ $b_i \leftarrow PartVerify(pd_i) \forall i \in [k]$ if any $b_i == 0$ then reject the share.

// fetch ct $ct = Storage.Get(cid)$ // TODO: we should probably just store this somewhere // it could even be embedded in the ciphertext itself // we should keep contract storage as small as possible $(ek, ak) \leftarrow Preprocess(CRS, \mathcal{U}, \{hint_i, pk_i\}_{i \in [\mathcal{U}]})$ $m = DecAggr(CRS, ak, ct, \{pd_1, ..., pd_k\})$