eth-offline

commit 4e92f53c42f59a1a032c1dbaa7e98650390c0ca3
parent 6802d8018d8b85e7e119a0f1d136a0cdb21c664a
Author: lash <dev@holbrook.no>
Date:   Mon, 13 Mar 2023 12:22:15 +0000

Make core abstract

Diffstat:
M
solidity/OfflineMinter.sol
 | 
17
+++++++++--------
A
solidity/OfflineMinterImplement.sol
 | 
12
++++++++++++

2 files changed, 21 insertions(+), 8 deletions(-)
diff --git a/solidity/OfflineMinter.sol b/solidity/OfflineMinter.sol
@@ -1,10 +1,12 @@
 pragma solidity ^0.8.0;
 
-contract OfflineMinter {
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+abstract contract OfflineMinter {
 
 	bytes26 constant prefix = bytes26(abi.encodePacked("0x19457468657265756d205369676e6564204d6573736167653a0a"));
 
-	function verifyRequest(address _owner, bytes memory _data, bytes memory _signature) public pure returns(bool) {
+	function verifyRequest(address _owner, bytes memory _data, bytes memory _signature) public view returns(bool) {
 		address beneficiary;
 		bytes memory extra;
 		bytes memory message;
@@ -13,11 +15,11 @@ contract OfflineMinter {
 		uint256 messageLengthLength;
 
 		(beneficiary, extra) = splitData(_data);
-		messageLength = uintToString(uint(_data.length));
+		messageLength = uintToString(uint(_data.length + 20));
 		messageLengthLength = bytes(messageLength).length;
 
-		message = new bytes(_data.length + 26 + messageLengthLength);
-		messageDigest = keccak256(abi.encodePacked(prefix, messageLength, _data));
+		message = new bytes(_data.length + 46 + messageLengthLength);
+		messageDigest = keccak256(abi.encodePacked(prefix, messageLength, address(this), _data));
 
 		return _owner == recoverSigner(messageDigest, _signature);
 	}
@@ -41,9 +43,7 @@ contract OfflineMinter {
 		return (address(bytes20(beneficiary)), extra);
 	}
 
-	function verifyExtraData(bytes memory _data) public pure {
-		revert('verification not implemented');
-	}
+	function verifyExtraData(bytes memory _data) public virtual pure;
 
 	// from https://solidity-by-example.org/signature/
 	function recoverSigner(bytes32 _ethSignedMessageHash, bytes memory _signature) public pure returns (address) {
@@ -76,6 +76,7 @@ contract OfflineMinter {
 		// implicitly return (r, s, v)
 	}
 
+	// https://ethereum.stackexchange.com/questions/10811/solidity-concatenate-uint-into-a-string
 	function uintToString(uint v) public pure returns (string memory str) {
 		uint maxlength = 100;
 		bytes memory reversed = new bytes(maxlength);
diff --git a/solidity/OfflineMinterImplement.sol b/solidity/OfflineMinterImplement.sol
@@ -0,0 +1,12 @@
+pragma solidity ^0.8.0;
+
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+import './OfflineMinter.sol';
+
+contract OfflineMinterImpl is OfflineMinter {
+
+	function verifyExtraData(bytes memory _data) public override pure {
+		_data;
+	}
+}