reentrancy

Overview

The Reentrancy library provides an API to check for and disallow reentrancy on a contract.

More information can be found in the specification.

Known Issues

While this can protect against both single-function reentrancy and cross-function reentrancy attacks, it WILL NOT PREVENT a cross-contract reentrancy attack.

Using the Library

Using the Reentrancy Guard

Once imported, using the Reentrancy Library can be done by calling one of the two functions. For more information, see the specification.

• is_reentrant() -> bool
• reentrancy_guard()

The reentrancy_guard function asserts is_reentrant() returns false.

Example

use reentrancy::reentrancy_guard;

abi MyContract {
    fn my_non_reentrant_function();
}

impl MyContract for Contract {
    fn my_non_reentrant_function() {
        reentrancy_guard();

        // my code here
    }
}