fromExternal

Validates an EIP-712 proof attached to an encrypted handle submitted by a user. On success, returns a typed handle ready for computation. Reverts if the proof is invalid, expired, or was issued for a different contract.

This is the entry point for all user-provided encrypted inputs. The user encrypts a value with the JS SDK, and the contract validates the proof on-chain before using the handle.

Supported types: ebool, euint16, euint256, eint16, eint256

TIP

The external* types enforce at the Solidity type level that unvalidated handles cannot be used in computations. You must call fromExternal first.

For constants and state initialization (not user data), see Wrap as Public Handle.

Usage

function deposit(externalEuint256 encryptedAmount, bytes calldata proof) external {
    // Validate the user's encrypted input
    euint256 amount = Nox.fromExternal(encryptedAmount, proof);

    // Now use the validated handle in computations
    euint256 newBalance = Nox.add(_balances[msg.sender], amount);
    Nox.allowThis(newBalance);
    Nox.allow(newBalance, msg.sender);
    _balances[msg.sender] = newBalance;
}

Signature

function fromExternal(externalEuint256 handle, bytes calldata proof) internal returns (euint256)