Merge pull request #2 from maxrobot/feature/rpc-calls

Feature/rpc calls

Author: Friedrich

contracts/Validation.sol

@@ -0,0 +1,113 @@
+// Copyright (c) 2016-2018 Clearmatics Technologies Ltd
+// SPDX-License-Identifier: LGPL-3.0+
+pragma solidity ^0.4.23;
+
+import "./ECVerify.sol";
+
+contract Validation {
+	address Owner;
+
+	event broadcastSig(address owner);
+	event broadcastHashData(bytes header, bytes parentHash, bytes rootHash);
+	event broadcastHash(bytes32 blockHash);
+
+	address[] validators;
+
+	/*
+	*	@param _validators			list of validators at block 0
+	*/
+	constructor (address[] _validators) public {
+		Owner = msg.sender;
+		for (uint i = 0; i < _validators.length; i++) {
+        validators.push(_validators[i]);
+    }
+	}
+
+	/*
+	*
+	*/
+	function GetValidators() public view returns (address[] _validators) {
+		return validators;
+	}
+
+	/*
+	* @param header  					header rlp encoded, with extraData signatures removed
+	* @param prefixHeader			the new prefix for the signed hash header
+	* @param prefixExtraData	the new prefix for the extraData field
+	*/
+	function ValidateBlock(bytes header, bytes prefixHeader, bytes prefixExtraData) public {
+		uint256 length = header.length;
+		bytes32 blockHash = keccak256(header);
+
+		emit broadcastHash(blockHash);
+
+		bytes memory headerStart 	= new bytes(length - 141);
+		bytes memory extraData 		= new bytes(31);
+		bytes memory extraDataSig	= new bytes(65);
+		bytes memory headerEnd 		= new bytes(42);
+
+		// Extract the start of the header and replace the length
+		extractData(headerStart, header, 0, headerStart.length);
+		assembly {
+           let ret := staticcall(3000, 4, add(prefixHeader, 32), 2, add(headerStart, 33), 2)
+    }
+
+		// Extract the real extra data and create the signed hash
+		extractData(extraData, header, length-140, extraData.length);
+		assembly {
+					 let ret := staticcall(3000, 4, add(prefixExtraData, 32), 1, add(extraData, 32), 1)
+		}
+
+		// Extract the end of the header
+		extractData(headerEnd, header, length-42, headerEnd.length);
+		bytes memory newHeader = mergeHash(headerStart, extraData, headerEnd);
+
+		bytes32 hashData = keccak256(newHeader);
+
+		// Extract the signature of the hash create above
+		extractData(extraDataSig, header, length-107, extraDataSig.length);
+
+		address sig_addr = ECVerify.ecrecovery(hashData, extraDataSig);
+
+		emit broadcastSig(sig_addr);
+
+	}
+
+	function mergeHash(bytes headerStart, bytes extraData, bytes headerEnd) internal view returns (bytes output) {
+		// Get the lengths sorted because they're needed later...
+		uint256 headerStartLength = headerStart.length;
+		uint256 extraDataLength = extraData.length;
+		uint256 extraDataStart = headerStartLength + 32;
+		uint256 headerEndLength = headerEnd.length;
+		uint256 headerEndStart = extraDataLength + headerStartLength + 32 + 2;
+		uint256 newLength = headerStartLength + extraDataLength + headerEndLength + 2; // extra two is for the prefix
+		bytes memory header = new bytes(newLength);
+
+
+		// Add in the first part of the header
+		assembly {
+			let ret := staticcall(3000, 4, add(headerStart, 32), headerStartLength, add(header, 32), headerStartLength)
+		}
+		assembly {
+			let ret := staticcall(3000, 4, add(extraData, 32), extraDataLength, add(header, extraDataStart), extraDataLength)
+		}
+		assembly {
+			let ret := staticcall(3000, 4, add(headerEnd, 32), headerEndLength, add(header, headerEndStart), headerEndLength)
+		}
+
+		output = header;
+	}
+
+	/*
+	* @param data	  			memory allocation for the data you need to extract
+	* @param sig    			array from which the data should be extracted
+	* @param start   			index which the data starts within the byte array
+	* @param length  			total length of the data to be extracted
+	*/
+	function extractData(bytes data, bytes input, uint start, uint length) private pure {
+		for (uint i=0; i<length; i++) {
+			data[i] = input[start+i];
+		}
+	}
+
+}

migrations/2_deploy_contracts.js

@@ -1,9 +1,12 @@
 const Recover = artifacts.require("Recover");
+const Validation = artifacts.require("Validation");
 
 module.exports = async (deployer) => {
   try {
     deployer.deploy(Recover)
       .then(() => Recover.deployed)
+      .then(() => deployer.deploy(Validation, ["0x2be5ab0e43b6dc2908d5321cf318f35b80d0c10d", "0x8671e5e08d74f338ee1c462340842346d797afd3"]))
+      .then(() => Validation.deployed)
   } catch(err) {
     console.log('ERROR on deploy:',err);
   }