Re:153k Ether Stolen in Parity Multi-Sig Attack
by RcouF1uZ4gsC on Wednesday July 19, 2017 @05:19PM
(#14808050)
What is "unpredictable behavior"? Per ethereum, the code is the specified behavior. Would a contract with function "GiveMeAllYourMoney" be unpredictable behavior if it did what it said. What if instead it was named "Execute"? So now we have a contract whose "unpredictable behavior" depends on how you name functions and variables. However, that is something that cannot be checked by a computer, but would have to be human checked. "Unpredictable behavior" likely would ultimately have to be adjudicated by a court. In that case, what has the smart contract bought you?
[ Parent
| on HN ]
Re:153k Ether Stolen in Parity Multi-Sig Attack
by grandalf on Wednesday July 19, 2017 @05:50PM
(#14808308)
I use the term unpredictable behavior simply to describe a case where the contract has behavior that was not fully anticipated by at leat one user of the contract.
Of course, the code is deterministic and so the behavior was unambiguously defined in the contract's source code.
But there exist all sorts of semantic bugs, which can at times be pretty subtle, which means that even for an expert, the mental model of code execution may not match reality.
If there were nondeterministic behavior in the Ethereum VM that would necessitate a fix to the VM and would likely be completely uncontroversial.