johnwhitton
commented
2 years ago Error calculating the seal when relaying blocks Here is the current error when relaying a block after putting some logging in EthereumLightClient.sol It is having trouble calling Analysis The block header for localgeth is as follows you can see sample blockHeaders from ropsten and ethereum here
header: {
"parentHash": "0xdb9e3369509518820f176b86afc312ecafc54a4bc324491bd261df3614b55735",
"uncleHash": "0x1dcc4de8dec75d7aab85b567b6ccd41ad312451b948a7413f0a142fd40d49347",
"coinbase": "0xf39fd6e51aad88f6f4ce6ab8827279cfffb92266",
"stateRoot": "0xadfd9a8868580138c975dcaed43c6f56035eb9e89bd63cb5ac67651b32075733",
"transactionsTrie": "0x56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421",
"receiptTrie": "0x56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421",
"logsBloom": "0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000",
"difficulty": "0x20000",
"number": "0x2",
"gasLimit": "0x7a4f0e",
"gasUsed": "0x0",
"timestamp": "0x62a8d530",
"extraData": "0xd983010a12846765746888676f312e31382e328664617277696e",
"mixHash": "0x233714ae9205bb1305214026b9335b113203dc51d4e68a876400c8936795f8d4",
"nonce": "0x76a1124da977aa93",
"bloom": "0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"
}EthereumParser.sol iterates through the header fields to calculate the sealRlpData
bytes[] memory rlpFields = new bytes[](14);
RLPReader.Iterator memory it = _rlpHeader.toRlpItem().iterator();
uint256 idx = 0;
while (it.hasNext() && idx < 14) {
console.log("idx: ", idx);
if (idx == 13) {
it.next();
it.next();
}
rlpFields[idx] = it.next().toRlpBytes();
idx++;
}The goal of the logic above is to ignore the following lines in the header file
"baseFeePerGas": "0x7",
"baseFee": "0x7",However for localgeth those lines are omitted (as with some of the earlier blocks in Ropsten.
The logic should be modified to conditionally skip the lines above only if they are populated.
This could be done by calculating the length of the header rows and replacing the hardocded skipping on idx ==13
The other option is to modify localgeth genesis.json to force it to add in the baseFee information.
Command
yarn cli ethRelay relay http://localhost:8645 http://localhost:8545 0x017f8C7d1Cb04dE974B8aC1a6B8d3d74bC74E7E1 -d ./src/cli/.dag
Error
console.log:
calling _pruneBlocks
checking blockExists
Parsing BlockHeader
checking Parentblock
checking block height
checking timestamp
checking difficulty
verifying block POW
Error: Transaction reverted without a reason string
at EthereumLightClient.next (contracts/lib/RLPReader.sol:33)
at EthereumLightClient.calcBlockSealHash (contracts/EthereumParser.sol:98)
at EthereumLightClient.addBlockHeader (contracts/EthereumLightClient.sol:178)
I’ve been looking at a problem with the deploy of the LightClient and narrowed it down to this line in
RLPReader.soluint mask = 256 ** (WORD_SIZE - len) - 1;When we are creating the rlpHeader the logsBloom is"logsBloom": "0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000”,which has a length of 256 (this is for Ropsten, and localgeth) Thus we were trying to go to a power of a negative number (which just failed without reverting or giving any error). I put in a workaround ofAnd the deploy is now working I noticed that the version of RLPReader we have was updated by Tuan Vu I’m assuming it was copied originally from here https://github.com/hamdiallam/Solidity-RLP/blob/master/contracts/RLPReader.sol#L351 This codebase was last modified on Jun 7 2021 and contracts have
pragma solidity >=0.5.0 <0.7.0;we are usingpragma solidity ^0.8.0;Also the code from hamdiallam has some additional error handling which may have been applied after we made the original copy. So there may be more cleanup work enhancements needed. Currently the relay is still failing withError: Transaction has been reverted by the EVM:latest log is here Fix was applied here.