Encrypted Types

The encrypted values are expressed aseuint on fhEVM, and the largest supported encrypted integer is up to 64 bits with euint64. Larger encrypted integer types (128, 256) will be supported in the future. As of now, the available encrypted types include:

• ebool

• euint4

• euint8

• euint16

• euint32

• euint64

• eaddress

• ebytes256

Please bear in mind that "revert on overflow" is not supported because it would leak information on the encrypted value.

Cipher texts generated on the client side are converted into euint types in the smart contract by casting with the TFHE.asEuint8 function. Here's an example:

function storeEncryptedValue(einput encryptedAmount, bytes calldata inputProof) public {
        euint8 hiddenScore = TFHE.asEuint8(encryptedAmount,inputProof);
}

The other casting functions include:

• TFHE.asEuint4

• TFHE.asEuint8

• TFHE.asEuint16

• TFHE.asEuint32

• TFHE.asEuint64

• TFHE.asEbytes256

• TFHE.asEbool

• TFHE.asEaddress

To generate a cipher text on the client side, please refer to this document:

Encryption & Re-encryption

Please note that the number of bits of the cipher text should match the euint type. For example, the value generated by input.add64(10) with fhevmjs can only be cast with TFHE.asEuint64 on the smart contract.