Line data    Source code

       1             : // SPDX-License-Identifier: MIT
       2             : 
       3             : pragma solidity ^0.6.0;
       4             : 
       5             : /*
       6             :  * @dev Solidity implementation of the ENS namehash algorithm.
       7             :  *
       8             :  * Warning! Does not normalize or validate names before hashing.
       9             :  * Original version can be found here https://github.com/JonahGroendal/ens-namehash/
      10             :  */
      11             : library ENSNamehash {
      12             :   function namehash(bytes memory domain) internal pure returns (bytes32) {
      13           0 :     return namehash(domain, 0);
      14             :   }
      15             : 
      16             :   function namehash(bytes memory domain, uint256 i) internal pure returns (bytes32) {
      17           0 :     if (domain.length <= i) return 0x0000000000000000000000000000000000000000000000000000000000000000;
      18             : 
      19           0 :     uint256 len = labelLength(domain, i);
      20             : 
      21           0 :     return keccak256(abi.encodePacked(namehash(domain, i + len + 1), keccak(domain, i, len)));
      22             :   }
      23             : 
      24             :   function labelLength(bytes memory domain, uint256 i) private pure returns (uint256) {
      25           0 :     uint256 len;
      26           0 :     while (i + len != domain.length && domain[i + len] != 0x2e) {
      27           0 :       len++;
      28             :     }
      29           0 :     return len;
      30             :   }
      31             : 
      32             :   function keccak(
      33             :     bytes memory data,
      34             :     uint256 offset,
      35             :     uint256 len
      36             :   ) private pure returns (bytes32 ret) {
      37           0 :     require(offset + len <= data.length);
      38             :     assembly {
      39           0 :       ret := keccak256(add(add(data, 32), offset), len)
      40             :     }
      41             :   }
      42             : }