28 lines
1.1 KiB
Solidity
28 lines
1.1 KiB
Solidity
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// SPDX-License-Identifier: BUSL-1.1
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pragma solidity =0.7.6;
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/// @title Prevents delegatecall to a contract
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/// @notice Base contract that provides a modifier for preventing delegatecall to methods in a child contract
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abstract contract NoDelegateCall {
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/// @dev The original address of this contract
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address private immutable original;
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constructor() {
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// Immutables are computed in the init code of the contract, and then inlined into the deployed bytecode.
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// In other words, this variable won't change when it's checked at runtime.
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original = address(this);
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}
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/// @dev Private method is used instead of inlining into modifier because modifiers are copied into each method,
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/// and the use of immutable means the address bytes are copied in every place the modifier is used.
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function checkNotDelegateCall() private view {
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require(address(this) == original);
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}
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/// @notice Prevents delegatecall into the modified method
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modifier noDelegateCall() {
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checkNotDelegateCall();
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_;
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}
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}
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