feat: new DecryptionOracle contract

contracts/.env.example

@@ -1,7 +1,7 @@
 export MNEMONIC="adapt mosquito move limb mobile illegal tree voyage juice mosquito burger raise father hope layer"
 export PRIVATE_KEY_FHEVM_DEPLOYER="0c66d8cde71d2faa29d0cb6e3a567d31279b6eace67b0a9d9ba869c119843a5e"
-export PRIVATE_KEY_GATEWAY_DEPLOYER="717fd99986df414889fd8b51069d4f90a50af72e542c58ee065f5883779099c6"
-export PRIVATE_KEY_GATEWAY_RELAYER="7ec931411ad75a7c201469a385d6f18a325d4923f9f213bd882bbea87e160b67"
+export PRIVATE_KEY_DECRYPTION_ORACLE_DEPLOYER="717fd99986df414889fd8b51069d4f90a50af72e542c58ee065f5883779099c6"
+export PRIVATE_KEY_DECRYPTION_ORACLE_RELAYER="7ec931411ad75a7c201469a385d6f18a325d4923f9f213bd882bbea87e160b67"
 export NUM_KMS_SIGNERS="1"
 export PRIVATE_KEY_KMS_SIGNER_0="388b7680e4e1afa06efbfd45cdd1fe39f3c6af381df6555a19661f283b97de91"
 export PRIVATE_KEY_KMS_SIGNER_1="bbaed91514fa4b7c86aa4f73becbabcf4bce0ae130240f0d6ac3f87e06812440"

contracts/.env.example.deployment

@@ -1,6 +1,6 @@
 export PRIVATE_KEY_FHEVM_DEPLOYER="0c66d8cde71d2faa29d0cb6e3a567d31279b6eace67b0a9d9ba869c119843a5e"
-export PRIVATE_KEY_GATEWAY_DEPLOYER="717fd99986df414889fd8b51069d4f90a50af72e542c58ee065f5883779099c6"
-export ADDRESS_GATEWAY_RELAYER="0x97F272ccfef4026A1F3f0e0E879d514627B84E69"
+export PRIVATE_KEY_DECRYPTION_ORACLE_DEPLOYER="717fd99986df414889fd8b51069d4f90a50af72e542c58ee065f5883779099c6"
+export ADDRESS_DECRYPTION_ORACLE_RELAYER="0x97F272ccfef4026A1F3f0e0E879d514627B84E69"
 export NUM_KMS_SIGNERS="4"
 export ADDRESS_KMS_SIGNER_0="0x0971C80fF03B428fD2094dd5354600ab103201C5"
 export ADDRESS_KMS_SIGNER_1="0xB68deCb047B5e6Cc82280502A7E2318c6b3E5eC6"

contracts/.npmignore

@@ -6,9 +6,9 @@
 !/artifacts/contracts/KMSVerifier.sol/KMSVerifier.json
 !/artifacts/contracts/TFHEExecutor.sol/TFHEExecutor.json
 !/artifacts/contracts/TFHEExecutorWithEvents.sol/TFHEExecutorWithEvents.json
-!/artifacts/gateway/GatewayContract.sol/GatewayContract.json
+!/artifacts/decryptionOracle/DecryptionOracle.sol/DecryptionOracle.json
 !contracts/**
-!gateway/**
+!decryptionOracle/**
 !package.json
 !LICENSE
 !README.md

contracts/addresses/.env.decryptionoracle

@@ -0,0 +1 @@
+DECRYPTION_ORACLE_ADDRESS=0x33347831500F1e73f0ccCBb95c9f86B94d7b1123

contracts/addresses/.env.fhegaslimit

@@ -1 +1 @@
-FHE_PAYMENT_CONTRACT_ADDRESS=0xFb03BE574d14C256D56F09a198B586bdfc0A9de2
+FHE_GASLIMIT_CONTRACT_ADDRESS=0xFb03BE574d14C256D56F09a198B586bdfc0A9de2

contracts/addresses/DecryptionOracleAddress.sol

@@ -0,0 +1,5 @@
+// SPDX-License-Identifier: BSD-3-Clause-Clear
+
+pragma solidity ^0.8.24;
+
+address constant DECRYPTION_ORACLE_ADDRESS = 0x33347831500F1e73f0ccCBb95c9f86B94d7b1123;

contracts/decryptionOracle/DecryptionOracle.sol

@@ -0,0 +1,91 @@
+// SPDX-License-Identifier: BSD-3-Clause-Clear
+
+pragma solidity ^0.8.24;
+
+import "@openzeppelin/contracts-upgradeable/access/Ownable2StepUpgradeable.sol";
+import "@openzeppelin/contracts-upgradeable/proxy/utils/UUPSUpgradeable.sol";
+import "@openzeppelin/contracts/utils/Strings.sol";
+
+contract DecryptionOracle is UUPSUpgradeable, Ownable2StepUpgradeable {
+    /// @notice Name of the contract
+    string private constant CONTRACT_NAME = "DecryptionOracle";
+
+    /// @notice Major version of the contract.
+    uint256 private constant MAJOR_VERSION = 0;
+
+    /// @notice Minor version of the contract.
+    uint256 private constant MINOR_VERSION = 1;
+
+    /// @notice Patch version of the contract.
+    uint256 private constant PATCH_VERSION = 0;
+
+    event DecryptionRequest(uint256 indexed requestID, uint256[] cts, address contractCaller, bytes4 callbackSelector);
+
+    function _authorizeUpgrade(address _newImplementation) internal virtual override onlyOwner {}
+
+    /// @custom:storage-location erc7201:fhevm.storage.DecryptionOracle
+    struct DecryptionOracleStorage {
+        uint256 counter; // tracks the number of decryption requests, and used to compute the requestID by hashing it with the dApp address
+    }
+
+    function getCounter() external virtual returns (uint256) {
+        DecryptionOracleStorage storage $ = _getDecryptionOracleStorage();
+        return $.counter;
+    }
+
+    // keccak256(abi.encode(uint256(keccak256("fhevm.storage.DecryptionOracle")) - 1)) & ~bytes32(uint256(0xff))
+    bytes32 private constant DecryptionOracleStorageLocation =
+        0xd86fa2a52e99634194c279afa011b5f5166614c3198dd09bbd002d5fb5c0bc00;
+
+    /**
+     * @dev Returns the DecryptionOracle storage location.
+     */
+    function _getDecryptionOracleStorage() internal pure returns (DecryptionOracleStorage storage $) {
+        assembly {
+            $.slot := DecryptionOracleStorageLocation
+        }
+    }
+
+    /// @custom:oz-upgrades-unsafe-allow constructor
+    constructor() {
+        _disableInitializers();
+    }
+
+    function initialize(address _decryptionOracleOwner) external initializer {
+        __Ownable_init(_decryptionOracleOwner);
+    }
+
+    /** @notice Requests the decryption of n ciphertexts `ctsHandles` with the result returned in a callback.
+     * @notice During callback, msg.sender is called with [callbackSelector,requestID,decrypt(ctsHandles[0]),decrypt(ctsHandles[1]),...,decrypt(ctsHandles[n-1]),signatures]
+     * @param ctsHandles is an array of uint256s handles.
+     * @param callbackSelector the callback selector to be called on msg.sender later during fulfilment
+     */
+    function requestDecryption(
+        uint256[] calldata ctsHandles,
+        bytes4 callbackSelector
+    ) external virtual returns (uint256 requestID) {
+        DecryptionOracleStorage storage $ = _getDecryptionOracleStorage();
+        requestID = uint256(keccak256(abi.encodePacked(msg.sender, $.counter)));
+        emit DecryptionRequest(requestID, ctsHandles, msg.sender, callbackSelector);
+        $.counter++;
+    }
+
+    /**
+     * @notice        Getter for the name and version of the contract.
+     * @return string Name and the version of the contract.
+     */
+    function getVersion() external pure virtual returns (string memory) {
+        return
+            string(
+                abi.encodePacked(
+                    CONTRACT_NAME,
+                    " v",
+                    Strings.toString(MAJOR_VERSION),
+                    ".",
+                    Strings.toString(MINOR_VERSION),
+                    ".",
+                    Strings.toString(PATCH_VERSION)
+                )
+            );
+    }
+}