EVM Bytecode Disassembler

disassembler.py

opcodes = {
    0x00: 'STOP',
    0x01: 'ADD',
    0x02: 'MUL',
    0x03: 'SUB',
    0x04: 'DIV',
    0x05: 'SDIV',
    0x06: 'MOD',
    0x07: 'SMOD',
    0x08: 'ADDMOD',
    0x09: 'MULMOD',
    0x0a: 'EXP',
    0x0b: 'SIGNEXTEND',
    0x10: 'LT',
    0x11: 'GT',
    0x12: 'SLT',
    0x13: 'SGT',
    0x14: 'EQ',
    0x15: 'ISZERO',
    0x16: 'AND',
    0x17: 'OR',
    0x18: 'XOR',
    0x19: 'NOT',
    0x1a: 'BYTE',
    0x1b: 'SHL',
    0x1c: 'SHR',
    0x1d: 'SAR',
    0x20: 'SHA3',
    0x30: 'ADDRESS',
    0x31: 'BALANCE',
    0x32: 'ORIGIN',
    0x33: 'CALLER',
    0x34: 'CALLVALUE',
    0x35: 'CALLDATALOAD',
    0x36: 'CALLDATASIZE',
    0x37: 'CALLDATACOPY',
    0x38: 'CODESIZE',
    0x39: 'CODECOPY',
    0x3a: 'GASPRICE',
    0x3b: 'EXTCODESIZE',
    0x3c: 'EXTCODECOPY',
    0x3d: 'RETURNDATASIZE',
    0x3e: 'RETURNDATACOPY',
    0x3f: 'EXTCODEHASH',
    0x46: 'CHAINID',
    0x47: 'SELFBALANCE',
    0x48: 'BASEFEE',
    0x40: 'BLOCKHASH',
    0x41: 'COINBASE',
    0x42: 'TIMESTAMP',
    0x43: 'NUMBER',
    0x44: 'DIFFICULTY',
    0x45: 'GASLIMIT',
    0x50: 'POP',
    0x51: 'MLOAD',
    0x52: 'MSTORE',
    0x53: 'MSTORE8',
    0x54: 'SLOAD',
    0x55: 'SSTORE',
    0x56: 'JUMP',
    0x57: 'JUMPI',
    0x58: 'PC',
    0x59: 'MSIZE',
    0x5a: 'GAS',
    0x5b: 'JUMPDEST',
    0x60: 'PUSH1',
    0x61: 'PUSH2',
    0x62: 'PUSH3',
    0x63: 'PUSH4',
    0x64: 'PUSH5',
    0x65: 'PUSH6',
    0x66: 'PUSH7',
    0x67: 'PUSH8',
    0x68: 'PUSH9',
    0x69: 'PUSH10',
    0x6a: 'PUSH11',
    0x6b: 'PUSH12',
    0x6c: 'PUSH13',
    0x6d: 'PUSH14',
    0x6e: 'PUSH15',
    0x6f: 'PUSH16',
    0x70: 'PUSH17',
    0x71: 'PUSH18',
    0x72: 'PUSH19',
    0x73: 'PUSH20',
    0x74: 'PUSH21',
    0x75: 'PUSH22',
    0x76: 'PUSH23',
    0x77: 'PUSH24',
    0x78: 'PUSH25',
    0x79: 'PUSH26',
    0x7a: 'PUSH27',
    0x7b: 'PUSH28',
    0x7c: 'PUSH29',
    0x7d: 'PUSH30',
    0x7e: 'PUSH31',
    0x7f: 'PUSH32',
    0x80: 'DUP1',
    0x81: 'DUP2',
    0x82: 'DUP3',
    0x83: 'DUP4',
    0x84: 'DUP5',
    0x85: 'DUP6',
    0x86: 'DUP7',
    0x87: 'DUP8',
    0x88: 'DUP9',
    0x89: 'DUP10',
    0x8a: 'DUP11',
    0x8b: 'DUP12',
    0x8c: 'DUP13',
    0x8d: 'DUP14',
    0x8e: 'DUP15',
    0x8f: 'DUP16',
    0x90: 'SWAP1',
    0x91: 'SWAP2',
    0x92: 'SWAP3',
    0x93: 'SWAP4',
    0x94: 'SWAP5',
    0x95: 'SWAP6',
    0x96: 'SWAP7',
    0x97: 'SWAP8',
    0x98: 'SWAP9',
    0x99: 'SWAP10',
    0x9a: 'SWAP11',
    0x9b: 'SWAP12',
    0x9c: 'SWAP13',
    0x9d: 'SWAP14',
    0x9e: 'SWAP15',
    0x9f: 'SWAP16',
    0xa0: 'LOG0',
    0xa1: 'LOG1',
    0xa2: 'LOG2',
    0xa3: 'LOG3',
    0xa4: 'LOG4',
    0xf0: 'CREATE',
    0xf1: 'CALL',
    0xf2: 'CALLCODE',
    0xf3: 'RETURN',
    0xf4: 'DELEGATECALL',
    0xf5: 'CREATE2',
    0xfa: 'STATICCALL',
    0xfd: 'REVERT',
    0xff: 'SELFDESTRUCT',
}

class Disassembler:

    def disassemble(code):
        idx = 0
        while idx < len(code):
            instruction = code[idx]
            opcode = opcodes[instruction] if instruction in opcodes else 'INVALID'

            if 'PUSH' not in opcode:
                print(f'{idx:4} {opcode}')
                idx += 1
                continue

            n = int(opcode[4:]) + 1
            s = code[idx+1:idx+n].hex()
            print(f'{idx:4} {opcode} 0x{s}')
            idx += n

    def selectors(code):
        selectors = []
        idx = 0
        while idx < len(code):
            instruction = code[idx]
            opcode = opcodes[instruction] if instruction in opcodes else 'INVALID'

            if 'PUSH' not in opcode:
                idx += 1
                continue

            n = int(opcode[4:])
            s = code[idx+1:idx+n+1].hex()
            idx += n + 1

            if n == 4:
                selectors.append(s)

        return set(selectors)