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Inco supports multiple ways to turn encrypted handles into plaintext, depending on who should learn the data and where the result must be consumed. This page summarizes the main flows and highlights how access control and signatures keep the data safe.

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Signatures and EIP-712

Attested flows (attestedDecrypt, attestedCompute) require the user to prove control over their address.
The JS SDK does this by asking the user to sign an EIP-712 message that binds:
  • the caller’s address,
  • the requested operation (decrypt, compute),
  • and the handles / parameters involved in the request.
This ensures that only the address that has on-chain access to a handle (via e.allow or e.reveal) can request an attestation for it, and prevents a malicious party from replaying or forging decryption/computation requests.

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Attested Decrypt

Use an off-chain covalidator to decrypt a handle for an authorized user and receive a signed attestation of the plaintext. Refer to Attested Decrypt for full examples. High-level flow:
  • A contract exposes an encrypted handle (e.g. created with e.rand()), and grants access with e.allow.
  • The authorized user calls zap.attestedDecrypt(...) from the JS SDK, which talks to the covalidator.
  • The response contains the plaintext plus the covalidator signature, enabling the user to post the plaintext back on-chain if needed.

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Attested Reveal

If the contract already called e.reveal(handle), anyone may request an attested decryption because the handle is considered public. See Attested Reveal. The SDK call zap.attestedReveal([...handles]) returns plaintexts plus signatures that can be re-submitted on-chain. Warning: once e.reveal runs, the ciphertext is public forever.

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Attested Compute

Sometimes the goal is to evaluate a predicate (e.g. creditScore >= 700) instead of exposing the raw value. Attested Compute executes the computation off-chain, still requiring the handle to be shared via e.allow or e.reveal. The SDK call zap.attestedCompute(...) returns the result (such as an ebool) alongside a covalidator signature so the decision can be verified on-chain without re-running the computation.