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Solidity API

MerkleProof​

_These functions deal with verification of Merkle Tree proofs.

note that this is a stripped down version of Open Zeppelin's MerkleProof. https://github.com/OpenZeppelin/openzeppelin-contracts/pull/3200

The proofs can be generated using the JavaScript library https://github.com/miguelmota/merkletreejs[merkletreejs]. Note: the hashing algorithm should be keccak256 and pair sorting should be enabled.

See test/utils/cryptography/MerkleProof.test.ts for some examples.

WARNING: You should avoid using leaf values that are 64 bytes long prior to hashing, or use a hash function other than keccak256 for hashing leaves. This is because the concatenation of a sorted pair of internal nodes in the merkle tree could be reinterpreted as a leaf value._

verifyCalldata​

function verifyCalldata(bytes32[] proof, bytes32 root, bytes32 leaf) internal pure returns (bool)

Returns true if a leaf can be proved to be a part of a Merkle tree defined by root. For this, a proof must be provided, containing sibling hashes on the branch from the leaf to the root of the tree. Each pair of leaves and each pair of pre-images are assumed to be sorted.

processProofCalldata​

function processProofCalldata(bytes32[] proof, bytes32 leaf) internal pure returns (bytes32)

Returns the rebuilt hash obtained by traversing a Merkle tree up from leaf using proof. A proof is valid if and only if the rebuilt hash matches the root of the tree. When processing the proof, the pairs of leafs & pre-images are assumed to be sorted.

_hashPair​

function _hashPair(bytes32 a, bytes32 b) private pure returns (bytes32)

_efficientHash​

function _efficientHash(bytes32 a, bytes32 b) private pure returns (bytes32 value)