Merge with official b2e2 github repo.

.gitattributes

@@ -0,0 +1 @@
+*.sol linguist-language=Solidity

README.md

@@ -14,7 +14,7 @@ The latest version of the sequence and entity relationship diagrams from the whi
 Make sure that your node JS version is 16.17.1 because some of the dependencies do not work with newer versions.
 
 ## Cloning the repository
-    git clone --recursive <<todo: official github repo URL>>
+    git clone --recursive https://github.com/B2E2/b2e2_contracts.git
 
 ## Installing Dependencies
     sudo npm global add truffle ganache ganache-cli

contracts/ClaimVerifier.sol

@@ -16,6 +16,7 @@ import "./ClaimCommons.sol";
 library ClaimVerifier {
     // Constants ERC-735
     uint256 constant public ECDSA_SCHEME = 1;
+    uint256 constant public PREFIXED_ECDSA_SCHEME = 2;
 
     // JSON parsing constants.
     uint256 constant MAX_NUMBER_OF_JSON_FIELDS = 20;
@@ -325,10 +326,10 @@ library ClaimVerifier {
 
     function verifySignature(address _subject, uint256 _topic, uint256 _scheme, address _issuer, bytes memory _signature, bytes memory _data) public view returns (bool __valid) {
          // Check for currently unsupported signature.
-        if(_scheme != ECDSA_SCHEME)
+        if(_scheme != ECDSA_SCHEME && _scheme != PREFIXED_ECDSA_SCHEME)
             return false;
 
-        address signer = getSignerAddress(claimAttributes2SigningFormat(_subject, _topic, _data), _signature);
+        address signer = getSignerAddress(claimAttributes2SigningFormat(_scheme, _subject, _topic, _data), _signature);
 
         if(isContract(_issuer)) {
             return signer == IdentityContract(_issuer).owner();
@@ -400,8 +401,11 @@ library ClaimVerifier {
         return getInt256Field(_fieldName, _data) <= JsmnSolLib.parseInt(_fieldContent);
     }
 
-    function claimAttributes2SigningFormat(address _subject, uint256 _topic, bytes memory _data) internal pure returns (bytes32 __claimInSigningFormat) {
-        return keccak256(abi.encodePacked(_subject, _topic, _data));
+    function claimAttributes2SigningFormat(uint256 _scheme, address _subject, uint256 _topic, bytes memory _data) internal pure returns (bytes32 __claimInSigningFormat) {
+        if(_scheme == ECDSA_SCHEME)
+          return keccak256(abi.encodePacked(_subject, _topic, _data));
+        else
+          return ECDSA.toEthSignedMessageHash(keccak256(abi.encodePacked(_subject, _topic, _data)));
     }
 
     function getSignerAddress(bytes32 _claimInSigningFormat, bytes memory _signature) internal pure returns (address __signer) {