// SPDX-License-Identifier: MIT pragma solidity ^0.8.28; contract EldoriaGateKernel { bytes4 private eldoriaSecret; mapping(address => Villager) public villagers; address public frontend; uint8 public constant ROLE_SERF = 1 << 0; uint8 public constant ROLE_PEASANT = 1 << 1; uint8 public constant ROLE_ARTISAN = 1 << 2; uint8 public constant ROLE_MERCHANT = 1 << 3; uint8 public constant ROLE_KNIGHT = 1 << 4; uint8 public constant ROLE_BARON = 1 << 5; uint8 public constant ROLE_EARL = 1 << 6; uint8 public constant ROLE_DUKE = 1 << 7; struct Villager { uint id; bool authenticated; uint8 roles; } constructor(bytes4 _secret) { eldoriaSecret = _secret; frontend = msg.sender; } modifier onlyFrontend() { assembly { if iszero(eq(caller(), sload(frontend.slot))) { revert(0, 0) } } _; } function authenticate(address _unknown, bytes4 _passphrase) external onlyFrontend returns (bool auth) { assembly { let secret := sload(eldoriaSecret.slot) auth := eq(shr(224, _passphrase), secret) mstore(0x80, auth) mstore(0x00, _unknown) mstore(0x20, villagers.slot) let villagerSlot := keccak256(0x00, 0x40) let packed := sload(add(villagerSlot, 1)) auth := mload(0x80) let newPacked := or(and(packed, not(0xff)), auth) sstore(add(villagerSlot, 1), newPacked) } } function evaluateIdentity(address _unknown, uint8 _contribution) external onlyFrontend returns (uint id, uint8 roles) { assembly { mstore(0x00, _unknown) mstore(0x20, villagers.slot) let villagerSlot := keccak256(0x00, 0x40) mstore(0x00, _unknown) id := keccak256(0x00, 0x20) sstore(villagerSlot, id) let storedPacked := sload(add(villagerSlot, 1)) let storedAuth := and(storedPacked, 0xff) if iszero(storedAuth) { revert(0, 0) } let defaultRolesMask := ROLE_SERF roles := add(defaultRolesMask, _contribution) if lt(roles, defaultRolesMask) { revert(0, 0) } let packed := or(storedAuth, shl(8, roles)) sstore(add(villagerSlot, 1), packed) } } function hasRole(address _villager, uint8 _role) external view returns (bool hasRoleFlag) { assembly { mstore(0x0, _villager) mstore(0x20, villagers.slot) let villagerSlot := keccak256(0x0, 0x40) let packed := sload(add(villagerSlot, 1)) let roles := and(shr(8, packed), 0xff) hasRoleFlag := gt(and(roles, _role), 0) } } }

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