mythril/myth

#!/usr/bin/env python
"""mythril.py: Bug hunting on the Ethereum blockchain

   http://www.github.com/b-mueller/mythril
"""

from mythril.ether import evm, util
from mythril.ether.contractstorage import get_persistent_storage
from mythril.ether.ethcontract import ETHContract
from mythril.ether.util import compile_solidity
from mythril.rpc.client import EthJsonRpc
from mythril.ipc.client import EthIpc
from mythril.rpc.exceptions import ConnectionError
from mythril.support import signatures
from mythril.support.loader import DynLoader
from mythril.exceptions import CompilerError
from mythril.analysis.symbolic import StateSpace
from mythril.analysis.callgraph import generate_graph
from mythril.analysis.security import fire_lasers
from ethereum import utils
from pathlib import Path
from json.decoder import JSONDecodeError
import logging
import json
import sys
import argparse
import os
import re


def searchCallback(code_hash, code, addresses, balances):
    print("Matched contract with code hash " + code_hash)

    for i in range(0, len(addresses)):
        print("Address: " + addresses[i] + ", balance: " + str(balances[i]))


def exitWithError(message):
    print(message)
    sys.exit()


parser = argparse.ArgumentParser(description='Bug hunting on the Ethereum blockchain')
parser.add_argument("solidity_file", nargs='*')


commands = parser.add_argument_group('commands')
commands.add_argument('-d', '--disassemble',  action='store_true', help='disassemble')
commands.add_argument('-g', '--graph', help='generate a control flow graph', metavar='OUTPUT_FILE')
commands.add_argument('-x', '--fire-lasers', action='store_true', help='detect vulnerabilities')
commands.add_argument('-t', '--trace', action='store_true', help='trace contract, use with --data (optional)')
commands.add_argument('-s', '--search', help='search the contract database', metavar='EXPRESSION')
commands.add_argument('--xrefs', action='store_true', help='get xrefs from a contract')
commands.add_argument('--hash', help='calculate function signature hash', metavar='SIGNATURE')
commands.add_argument('--storage', help='read data from storage index, use with -a', metavar='INDEX')
commands.add_argument('--init-db', action='store_true', help='initialize the contract database')

inputs = parser.add_argument_group('input arguments')
inputs.add_argument('-c', '--code', help='hex-encoded bytecode string ("6060604052...")', metavar='BYTECODE')
inputs.add_argument('-a', '--address', help='pull contract from the blockchain', metavar='CONTRACT_ADDRESS')
inputs.add_argument('-l', '--dynld', action='store_true', help='auto-load dependencies (experimental)')
inputs.add_argument('--data', help='message call input data for tracing')

rpc = parser.add_argument_group('RPC options')
rpc.add_argument('--rpchost', default='127.0.0.1', help='RPC host')
rpc.add_argument('--rpcport', type=int, default=8545, help='RPC port')
rpc.add_argument('--rpctls', type=bool, default=False, help='RPC port')

presets = parser.add_argument_group('RPC presets')
presets.add_argument('--ganache', action='store_true', help='Use local Ganache')
presets.add_argument('--infura-mainnet', action='store_true', help='Use Infura Node service (Mainnet)')
presets.add_argument('--infura-rinkeby', action='store_true', help='Use Infura Node service (Rinkeby)')
presets.add_argument('--infura-kovan', action='store_true', help='Use Infura Node service (Kovan)')
presets.add_argument('--infura-ropsten', action='store_true', help='Use Infura Node service (Ropsten)')

options = parser.add_argument_group('options')
options.add_argument('--ipc', help='use IPC interface instead of RPC', action='store_true')
options.add_argument('--sync-all', action='store_true', help='Also sync contracts with zero balance')
options.add_argument('--max-depth', type=int, default=12, help='Maximum recursion depth for symbolic execution')
options.add_argument('--enable-physics', type=bool, default=False, help='enable graph physics simulation')
options.add_argument('-v', type=int, help='log level (0-2)', metavar='LOG_LEVEL')

# Get config values

try:
    mythril_dir = os.environ['MYTHRIL_DIR']
except KeyError:
    mythril_dir = os.path.join(os.path.expanduser('~'), ".mythril")

try:
    solc_binary = os.environ['SOLC']
except KeyError:
    solc_binary = 'solc'


# Initialize data directry and singature database

if not os.path.exists(mythril_dir):
    logging.info("Creating mythril data directory")

    os.mkdir(mythril_dir)
    

# If no function signature file exists, create it. Function signatures from Solidity source code are added automatically.

signatures_file = os.path.join(mythril_dir, 'signatures.json')

if not os.path.exists(signatures_file):
    print("No signature database found. Creating empty database: " + signatures_file  + "\n" \
        "Consider replacing it with the pre-initialized database at " \
        "https://raw.githubusercontent.com/ConsenSys/mythril/master/signatures.json")

    sigs = {}

    with open(signatures_file, 'a') as f:
        json.dump({},f)

else:
    with open(signatures_file) as f:
        try:
            sigs = json.load(f)
        except JSONDecodeError as e:
            exitWithError("Invalid JSON in signatures file " + signatures_file + "\n" + str(e))

# Parse cmdline args

args = parser.parse_args()

if not (args.search or args.init_db or args.hash or args.disassemble or args.graph or args.xrefs or args.fire_lasers or args.trace or args.storage):
    parser.print_help()
    sys.exit()

if (args.v):
    if (0 <= args.v < 3):
        logging.basicConfig(level=[logging.NOTSET, logging.INFO, logging.DEBUG][args.v])

elif (args.hash):
    print("0x" + utils.sha3(args.hash)[:4].hex())
    sys.exit()

# Establish RPC/IPC connection if necessary

if (args.address or len(args.solidity_file) or args.init_db):
        if args.ipc:
            eth = EthIpc()
        else:
            if args.infura_mainnet:
                eth = EthJsonRpc('mainnet.infura.io', 443, True)
            elif args.infura_rinkeby:
                eth = EthJsonRpc('rinkeby.infura.io', 443, True)
            elif args.infura_kovan:
                eth = EthJsonRpc('kovan.infura.io', 443, True)
            elif args.infura_ropsten:
                eth = EthJsonRpc('ropsten.infura.io', 443, True)
            elif args.ganache:
                eth = EthJsonRpc('localhost', 7545, False)
            else:
                eth = EthJsonRpc(args.rpchost, args.rpcport, args.rpctls)


# Database search ops

if args.search or args.init_db:

    contract_storage = get_persistent_storage(mythril_dir)

    if (args.search):

        try:
            contract_storage.search(args.search, searchCallback)
        except SyntaxError:
            exitWithError("Syntax error in search expression.")

    elif (args.init_db):
            contract_storage.initialize(eth, args.sync_all)

    sys.exit()


# Load / compile input contracts

contracts = []

if (args.code):
    contracts.append(ETHContract(args.code, name="MAIN", address = util.get_indexed_address(0)))
elif (args.address):

    if not re.match(r'0x[a-fA-F0-9]{40}', args.address):
        exitWithError("Invalid contract address. Expected format is '0x...'.")

    try:
        code = eth.eth_getCode(args.address)

        if (code == "0x"):
            exitWithError("Received an empty response from eth_getCode. Check the contract address and verify that you are on the correct chain.") 
    except ConnectionError:
        exitWithError("Error connecting to Ethereum node. Make sure that your node is up and that the provided RPC/IPC parameters are correct.")

    contracts.append(ETHContract(code, name=args.address, address = args.address))
elif (len(args.solidity_file)):
    index = 0

    for file in args.solidity_file:

        file = file.replace("~", str(Path.home())) # Expand user path

        signatures.add_signatures_from_file(file, sigs)

        logging.debug("Adding function signatures from source code:\n" + str(sigs))

        try:
            name, bytecode = compile_solidity(solc_binary, file)
        except CompilerError as e:
            exitWithError(e)

        # Max. 16 input files supported!

        contract = ETHContract(bytecode, name = name, address = util.get_indexed_address(index))
        index += 1

        contracts.append(contract)
        logging.info(contract.name + " at " + contract.address)

    # Save updated signature

    with open(signatures_file, 'w') as f:
        json.dump(sigs, f)

else:
    exitWithError("No input bytecode. Please provide EVM code via -c BYTECODE, -a ADDRESS, or -i SOLIDITY_FILES")

# Commands

if args.storage:
    if not args.address:
        exitWithError("To read storage, provide the address of a deployed contract with the -a option.")  
    else:
        try:
            position = int(args.storage)
        except ValueError:
            exitWithError("Invalid storage index. Please provide a numeric value.")  

        print(eth.eth_getStorageAt(args.address, position=position, block='latest'))

elif (args.disassemble):

    easm_text = contracts[0].get_easm()
    sys.stdout.write(easm_text)

elif (args.trace):

    if (args.data):
        trace = evm.trace(contracts[0].code, args.data)

    else:
        trace = evm.trace(contracts[0].code)

    for i in trace:
        if (re.match(r'^PUSH.*', i['op'])):
            print(str(i['pc']) + " " + i['op'] + " " + i['pushvalue'] + ";\tSTACK: " + i['stack'])
        else:
            print(str(i['pc']) + " " + i['op'] + ";\tSTACK: " + i['stack'])

elif (args.xrefs):

    print("\n".join(contracts[0].get_xrefs()))

elif (args.graph) or (args.fire_lasers):

    if (args.graph):

        if (args.dynld):
            states = StateSpace(contracts, dynloader=DynLoader(eth), max_depth=args.max_depth)
        else:
            states = StateSpace(contracts, max_depth=args.max_depth)

        if args.enable_physics is not None:
            physics = True

        html = generate_graph(states, args.enable_physics)

        try:
            with open(args.graph, "w") as f:
                f.write(html)
        except Exception as e:
            print("Error saving graph: " + str(e))

    else:

        if (args.dynld):
            states = StateSpace(contracts, dynloader=DynLoader(eth), max_depth=args.max_depth)
        else:
            states = StateSpace(contracts, max_depth=args.max_depth)

        fire_lasers(states)

else:
    parser.print_help()