块头rlp中的块散列

Question

给定块头的RLP，如何获得块哈希？

https://github.com/ethereum/go-ethereum/blob/master/core/types/block.go#L99

上面的链接是:哈希返回报头的块哈希，这就是它的RLP编码的keccak256哈希。

使用本例中的值(https://github.com/ethereum/tests/blob/develop/BlockchainTests/bcRandomBlockhashTest/randomStatetest109BC.json#L30)，我尝试在这里获取RLP值，在其上应用Keccak256函数，并查看是否可以返回上述哈希值。

示例：- rlp："0xf90267f901fca09d6563c8b.............................47d2e96bfdffc0"，Hash:"0xc061b982e871fb4a41bfee1a4e6aa859df15ac44bdc23643cb072c4d2b9e7ba1“

给定块头RLP，我无法重新创建上述块哈希值。请给我任何建议。

Answer 1

下面是计算blockHash的步骤，给定一个blockNumber：

Step1。eth.getBlock(400000)

输出：{ hash：'6022643743806'，extraData：'0xd583010202844765746885676f312e35856c696e7578'，gasLimit: 3141592，gasUsed: 0，hash：'0x5d15649e25d8f3e2c0374946078539d200710afc977cdfc6a977bd23f20fa8e8'，logsBloom：'0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000'，miner：‘0x2a65Aca4D5fC5C8590a6c34d164135398226’，mixHash：'0x3fbea7af642a4e20cd93a945a1f5e23bd72fc5261153e09102cf718980aeff38'，nonce：'0x6af23caae95692ef'，编号: 400000，parentHash：'0x1e77d8f1267348b516ebc4f4da1e2aa59f85f0cbd853949500ffac8bfc38ba14'，receiptsRoot：'0x56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421'，sha3Uncles：'0x1dcc4de8dec75d7aab85b567b6ccd41ad312451b948a7413f0a142fd40d49347'，size: 539，mixHash：'2014130882275463845'，transactions：[]，parentHash:en8 en8 en8#叔叔们：[] }

上面的对象中的散列引用了我们正在尝试验证的blockHash。这是实际的输出，稍后将用于比较测试结果。

Step2。从上面的对象中删除一些元素，只保留那些输入到blockHeader中的元素，然后按如下方式重新排序：

[‘'ParentHash'，'0x1e77d8f1267348b516ebc4f4da1e2aa59f85f0cbd853949500ffac8bfc38ba14’，‘'UncleHash'，'0x1dcc4de8dec75d7aab85b567b6ccd41ad312451b948a7413f0a142fd40d49347’，“‘Coinbase”，’0x2a65Aca4D5fC5B5C8590a6c34d164135398226‘，“”，‘0x0b5e4386680f43c224c5c037efc0b645c8e1c3f6b30da0eec07272b4e6f8cd89‘根，‘'TxHash'，'0x56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421’，‘'ReceiptHash'，'0x56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421’，“”，‘0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000‘布鲁姆，“困难”，6022643743806，“号码”，“0x400000”，“GasLimit”，3141592，“GasUsed”，0，“时间”，1445130204，“”，‘0xd583010202844765746885676f312e35856c696e7578‘额外，‘'MixDigest'，'0x3fbea7af642a4e20cd93a945a1f5e23bd72fc5261153e09102cf718980aeff38’，“无”，“0x6af23caae95692ef”]

Step3。将带有数字的值转换为十六进制

console.log(web3.utils.toHex(gasLimit));
console.log(web3.utils.toHex(gasUsed));
console.log(web3.utils.toHex(time));
console.log(web3.utils.toHex(difficulty));
console.log(web3.utils.toHex(number));

Step4。对于值为0的元素，请使用0x而不是0x0。

示例:对于块400000，gasUsed的值为0。所以用于gasUsed的值应该是0x，而不是0x0。

Step5。在将数字更改为十六进制并使用0处理值之后，我们可以继续删除Step2中列出的所有键，并调整数组如下：

‘0x1e77d8f1267348b516ebc4f4da1e2aa59f85f0cbd853949500ffac8bfc38ba14’，‘0x1dcc4de8dec75d7aab85b567b6ccd41ad312451b948a7413f0a142fd40d49347’，‘0x2a65aca4d5fc5b5c8590a6c34d164135398226’，‘0x0b5e4386680f43c224c5c037efc0b645c8e1c3f6b30da0eec07272b4e6f8cd89’，‘0x56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421’，‘0x56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421’，‘0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000’，‘0x57a418a7c3e’，‘0x61a80’，‘0x2fefd8’，‘0x’，‘0x5622‘0x1e77d8f1267348b516ebc4f4da1e2aa59f85f0cbd853949500ffac8bfc38ba14’，‘0x1dcc4de8dec75d7aab85b567b6ccd41ad312451b948a7413f0a142fd40d49347’，‘0x2a65aca4d5fc5b5c8590a6c34d164135398226’，‘0x0b5e4386680f43c224c5c037efc0b645c8e1c3f6b30da0eec07272b4e6f8cd89’，‘0x56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421’，‘0x56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421’，‘0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000’，‘0x57a418a7c3e’，‘0x61a80’，‘0x2fefd8’，‘0x’，‘0x5622’，‘0xd583010202844765746885676f312e35856c696e7578’，‘0x3fbea7af642a4e20cd93a945a1f5e23bd72fc5261153e09102cf718980aeff38’，‘0x6af23caae95692ef‘’，’0xd583010202844765746885676f312e35856c696e7578‘，’0x3fbea7af642a4e20cd93a945a1f5e23bd72fc5261153e09102cf718980aeff38‘，’0x6af23caae95692ef‘

Step6。现在可以将上面的值数组输入到rlp.encode函数中。

输出: 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

Step7。通过keccak256函数传递上述RLP。以下是产出：

TestOutput: 0x5d15649e25d8f3e2c0374946078539d200710afc977cdfc6a977bd23f20fa8e8 ActualOutput: 0x5d15649e25d8f3e2c0374946078539d200710afc977cdfc6a977bd23f20fa8e8

结论:使用eth.getBlock()。以它返回的对象作为输出。删除不需要的元素，只保留那些输入到blockHeader的元素。将数字转换为十六进制，并使用0处理值。重组对象以形成字符串数组。将此数组传递到rlp.encode函数中。获取rlp输出并在其上应用keccak256散列。

链接：https://github.com/ethereum/go-ethereum/blob/master/core/types/block.go#L69