mirror of
https://github.com/ethereum/solidity
synced 2023-10-03 13:03:40 +00:00
37 lines
1.3 KiB
Solidity
37 lines
1.3 KiB
Solidity
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pragma experimental SMTChecker;
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/**
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* @title MerkleProof
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* @dev Merkle proof verification based on
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* https://github.com/ameensol/merkle-tree-solidity/blob/master/src/MerkleProof.sol
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*/
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library MerkleProof {
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/**
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* @dev Verifies a Merkle proof proving the existence of a leaf in a Merkle tree. Assumes that each pair of leaves
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* and each pair of pre-images are sorted.
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* @param proof Merkle proof containing sibling hashes on the branch from the leaf to the root of the Merkle tree
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* @param root Merkle root
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* @param leaf Leaf of Merkle tree
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*/
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function verify(bytes32[] memory proof, bytes32 root, bytes32 leaf) internal pure returns (bool) {
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bytes32 computedHash = leaf;
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for (uint256 i = 0; i < proof.length; i++) {
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bytes32 proofElement = proof[i];
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if (computedHash < proofElement) {
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// Hash(current computed hash + current element of the proof)
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computedHash = keccak256(abi.encodePacked(computedHash, proofElement));
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} else {
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// Hash(current element of the proof + current computed hash)
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computedHash = keccak256(abi.encodePacked(proofElement, computedHash));
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}
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}
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// Check if the computed hash (root) is equal to the provided root
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return computedHash == root;
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}
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}
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// ----
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