Only two functions detected in smart contract with ten functions

[crytic]

Only two functions detected in smart contract with ten functions

[montyly]

Hi @kmbarry1, thank you for reporting this

My best guess is that the function dispatcher heuristic is not robust for contracts compiled with Solidity >0.5. We will take a closer look in the upcoming days

[montyly]

Hi @Pindapinda
Thank you for reporting this. We will look into it as soon as possible

[kmbarry1]

I'm running into the same issue--I pulled the bytecode for the DAI token:

0x6B175474E89094C44Da98b954EedeAC495271d0F

And ran it through the following script:

import pprint
import sys
from evm_cfg_builder.cfg import CFG

if len(sys.argv) != 2:
    print('Usage python print_function_selectors.py contract.evm')
    exit(-1)

with open(sys.argv[1]) as f:
    runtime_bytecode = f.read()

cfg = CFG(runtime_bytecode)

for function in sorted(cfg.functions, key=lambda x: x.start_addr):
    print('{} : {}'.format(function.hash_id, function.name))

obtaining the following output:

-2 : _dispatcher
2835717307 : transfer(address,uint256)
2127478272 : nonces(address)
-1 : _fallback
2835717307 : transfer(address,uint256)
3075713420 : push(address,uint256)
3140843579 : move(address,address,uint256)
3207937467 : 0xbf353dbb
3714247998 : allowance(address,address)
4074100075 : pull(address,uint256)

which doesn't even include transferFrom(address,address,uint256) (which has a function selector of 0x23b872dd, so it's not the one without a name match).