mock-coprocessor

A long-running TypeScript daemon that imitates the production FHEVM coprocessor for the purposes of mocked testnet experimentation. It polls the deployed FHEVMExecutor and ConfidentialBridge on every configured chain, replays each FHE operation in plaintext, and stores the result in a shared SQLite DB.

Scope. No real cryptography, no FHE, no MPC. Operates on event logs + arithmetic + a small EIP-712-signed input-bundle builder that mirrors what the production relayer would emit. Suitable for end-to-end integration smoke tests; not suitable as a stand-in for a real coprocessor in any security context.

Architecture

                          ┌───────────────────────────┐
  RPC: Sepolia ──poll──▶  │  chain-worker (sepolia)   │  ─┐
                          └───────────────────────────┘   │
                                                          ├─▶  MockDb (SQLite)
                          ┌───────────────────────────┐   │      handle → clearText
  RPC: Amoy    ──poll──▶  │  chain-worker (amoy)      │  ─┘
                          └───────────────────────────┘

• One chain worker per supported chain, polling eth_getLogs for the FHEVMExecutor + ConfidentialBridge addresses snapshotted in that chain's <chain>/addresses/.env.host.
• Logs are parsed against the same event ABI used by test/coprocessorUtils.ts (abi/events.ts) and dispatched to a handler:
  • handlers/fhe-executor.ts — full operator coverage (TrivialEncrypt, FheAdd/Sub/Mul/Div/Rem/BitAnd/BitOr/…/IfThenElse/Sum/IsIn/MulDiv/Rand/…). Ported from test/coprocessorUtils.ts::insertHandleFromEvent.
  • handlers/bridge.ts — on HandleBridged copies the source-chain clearText into the destination handle. Cross-chain races (chain B's HandleBridged seen before chain A's TrivialEncrypt) are resolved by a pending-mappings retry queue. Also handles FallbackGrantedPlaintext.
• A shared SQLite DB stores (handle → clearText) so the separate pnpm mock:query process can read them.