# Confidential Assets: Production Readiness

[ganymedio]

Confidential Assets: Production Readiness

Summary

Upgrades Movement's confidential-asset TS SDK to production readiness by adding proof-replay and key-registration protections, restoring batch range proofs, and pointing the SDK at the framework module address.

Changes

1. Domain-separated Fiat-Shamir with chain ID + address binding — new src/crypto/fiatShamir.ts. Challenges are SHA2-512 over a DST prefix (MovementConfidentialAsset/<protocol>) followed by chainId, senderAddress, and the remaining public inputs (matching the on-chain new_scalar_from_sha2_512). Binding chainId and the addresses prevents proof replay across chains and transaction contexts. The old genFiatShamirChallenge in helpers.ts (raw concatenation, no domain separation) is deprecated and unused.
2. Registration proof (ZKPoK of decryption key) — new src/crypto/confidentialRegistration.ts. Registration now requires a Schnorr proof that the registrant controls the decryption key, preventing registration of an encryption key you don't own.
3. Batch range proofs restored — all four proof types (transfer, withdrawal, normalization, key rotation) use genBatchRangeZKP, matching the on-chain verifier which expects a single batched Bulletproof per component.
4. Module address is the framework (0x1) — DEFAULT_CONFIDENTIAL_COIN_MODULE_ADDRESS and the e2e test-helper default are both 0x1; confidential asset now lives in the framework, not a standalone deploy address.
5. WASM bindings — pinned to @moveindustries/confidential-asset-wasm-bindings@0.0.5 (package.json plus the WASM URLs in rangeProof.ts and twistedElGamal.ts).

CI & localnet fixes

• CA E2E workflow pins APTOS_CORE_COMMIT to the aptos-core commit whose framework + Bulletproof DST match the wasm-bindings version (older pins fail with ERANGE_PROOF_VERIFICATION_FAILED). Since confidential_asset now lives at 0x1, the old publish-address extraction was removed.
• Localnet no longer depends on devnet. src/cli/localNode.ts previously set ENABLE_KEYLESS_DEFAULT=1, which made the node fetch the keyless Groth16 VK from devnet at genesis — a devnet outage crashed every e2e localnet. It now seeds the VK from a checked-in fixture (src/cli/keylessGroth16Vk.json) via INSTALL_KEYLESS_GROTH16_VK_FROM_PATH.
• Two pre-existing e2e tests fixed, surfaced once the localnet booted again: api/staking.test.ts coerces num_active_delegator (the indexer returns it as a string) before numeric comparison; client/get.test.ts deterministically verifies request overrides against an unreachable host instead of relying on a live network.

Test Plan

Requires a local Movement node from the aptos-core branch that ships the confidential asset framework and the localnet helper script (e.g. movementlabsxyz/aptos-core#299). The script enables feature flag 87 (BULLETPROOFS_BATCH_NATIVES), publishes the framework, and sets the chain auditor (required for transfers under #328).

1. Start the localnet + configure the chain auditor (in aptos-core):

cd ../aptos-core
./scripts/start-localnet-confidential-assets.sh
# Optional: override the default test auditor key
# CHAIN_AUDITOR_EK=0x<pubkey> ./scripts/start-localnet-confidential-assets.sh

2. Run the e2e tests against it (in this repo):

cd confidential-assets
MOVEMENT_NETWORK=local pnpm jest tests/e2e --globalSetup= --globalTeardown=

MOVEMENT_NETWORK=local targets the external node; --globalSetup= --globalTeardown= disables the SDK's own localnet-spawning hooks so it doesn't start a second node. The module address defaults to 0x1, so no extra env var is needed.

Results: the full pnpm jest run is 102 passing, 23 skipped, 0 failing across 8 suites, including all confidential-asset e2e tests (43 across confidentialAsset.test.ts and confidentialAssetTxnBuilder.test.ts). The skipped tests are legacy from a previous version of confidential assets and can be ignored.

Note: the contract now rejects self-transfers (ESELF_TRANSFER), so the transfer e2e tests send to a distinct registered recipient, and there is a dedicated test asserting that a self-transfer aborts.