Submission Details
Severity:
`assert` in `request_raffle_winner` prevent user from understanding why the function reverts
Description
To end, Snek Raffle needs to last at least 1 day, have one player, be open, and have a balance. However, the same error is returned for any of these conditions, preventing a user from understanding why the function reverts.
def request_raffle_winner() -> uint256:
"""Request a random winner from the VRF Coordinator after a raffle has completed."""
is_open: bool = RaffleState.OPEN == self.raffle_state
time_passed: bool = (block.timestamp - self.last_timestamp) > RAFFLE_DURATION
has_players: bool = len(self.players) > 0
has_balance: bool = self.balance > 0
self.raffle_state = RaffleState.CALCULATING
request_id: uint256 = VRF_COORDINATOR.requestRandomWords(
# c gas lane dans chainlink permet de definir du premium
GAS_LANE,
SUBSCRIPTION_ID,
REQUEST_CONFIRMATIONS,
CALLBACK_GAS_LIMIT,
NUM_WORDS
)
return ERC721._total_supply()
Risk
Likelyhood: Low
Occurs every time someone calls the function and all conditions are not satisfied.
Impact: Low
Impossible for a user to know why the function reverts.
Recommended Mitigation
Create separate error messages for each condition to provide more clarity to the user and add them in the function like below.
def request_raffle_winner() -> uint256:
"""Request a random winner from the VRF Coordinator after a raffle has completed."""
is_open: bool = RaffleState.OPEN == self.raffle_state
time_passed: bool = (block.timestamp - self.last_timestamp) > RAFFLE_DURATION
has_players: bool = len(self.players) > 0
has_balance: bool = self.balance > 0
- assert is_open and time_passed and has_players and has_balance, ERROR_NOT_ENDED
+ assert is_open, ERROR_NOT_OPEN
+ assert time_passed, ERROR_NOT_ENDED
+ assert has_players, ERROR_NO_PLAYER
+ assert has_balance, ERROR_NO_BALANCE
self.raffle_state = RaffleState.CALCULATING
request_id: uint256 = VRF_COORDINATOR.requestRandomWords(
# c gas lane dans chainlink permet de definir du premium
GAS_LANE,
SUBSCRIPTION_ID,
REQUEST_CONFIRMATIONS,
CALLBACK_GAS_LIMIT,
NUM_WORDS
)
return ERC721._total_supply()
Rewards breakdown
nSLOC
136This contest has a flat reward structure with the following payouts:
100 EXP
20 EXP
2 EXP
Live
The contest is live. Earn rewards by submitting a finding.
Appeals
This is your time to appeal against judgements on your submissions.
Appeals Review
Appeals are being carefully reviewed by our judges.