use crate::{ proofs::{EMPTY_LIST_HASH, EMPTY_ROOT}, BlockHash, BlockNumber, Bloom, H160, H256, U256, }; use bytes::{BufMut, BytesMut}; use ethers_core::{types::H64, utils::keccak256}; use reth_codecs::main_codec; use reth_rlp::{length_of_length, Decodable, Encodable}; use std::ops::Deref; /// Block header #[main_codec] #[derive(Debug, Clone, PartialEq, Eq, Hash)] pub struct Header { /// The Keccak 256-bit hash of the parent /// block’s header, in its entirety; formally Hp. pub parent_hash: H256, /// The Keccak 256-bit hash of the ommers list portion of this block; formally Ho. pub ommers_hash: H256, /// The 160-bit address to which all fees collected from the successful mining of this block /// be transferred; formally Hc. pub beneficiary: H160, /// The Keccak 256-bit hash of the root node of the state trie, after all transactions are /// executed and finalisations applied; formally Hr. pub state_root: H256, /// The Keccak 256-bit hash of the root node of the trie structure populated with each /// transaction in the transactions list portion of the /// block; formally Ht. pub transactions_root: H256, /// The Keccak 256-bit hash of the root /// node of the trie structure populated with the receipts of each transaction in the /// transactions list portion of the block; formally He. pub receipts_root: H256, /// The Bloom filter composed from indexable information (logger address and log topics) /// contained in each log entry from the receipt of each transaction in the transactions list; /// formally Hb. pub logs_bloom: Bloom, /// A scalar value corresponding to the difficulty level of this block. This can be calculated /// from the previous block’s difficulty level and the timestamp; formally Hd. pub difficulty: U256, /// A scalar value equal to the number of ancestor blocks. The genesis block has a number of /// zero; formally Hi. pub number: BlockNumber, /// A scalar value equal to the current limit of gas expenditure per block; formally Hl. pub gas_limit: u64, /// A scalar value equal to the total gas used in transactions in this block; formally Hg. pub gas_used: u64, /// A scalar value equal to the reasonable output of Unix’s time() at this block’s inception; /// formally Hs. pub timestamp: u64, /// An arbitrary byte array containing data relevant to this block. This must be 32 bytes or /// fewer; formally Hx. pub extra_data: bytes::Bytes, /// A 256-bit hash which, combined with the /// nonce, proves that a sufficient amount of computation has been carried out on this block; /// formally Hm. pub mix_hash: H256, /// A 64-bit value which, combined with the mixhash, proves that a sufficient amount of /// computation has been carried out on this block; formally Hn. pub nonce: u64, /// A scalar representing EIP1559 base fee which can move up or down each block according /// to a formula which is a function of gas used in parent block and gas target /// (block gas limit divided by elasticity multiplier) of parent block. /// The algorithm results in the base fee per gas increasing when blocks are /// above the gas target, and decreasing when blocks are below the gas target. The base fee per /// gas is burned. pub base_fee_per_gas: Option, } impl Default for Header { fn default() -> Self { Header { parent_hash: Default::default(), ommers_hash: EMPTY_LIST_HASH, beneficiary: Default::default(), state_root: EMPTY_ROOT, transactions_root: EMPTY_ROOT, receipts_root: EMPTY_ROOT, logs_bloom: Default::default(), difficulty: Default::default(), number: 0, gas_limit: 0, gas_used: 0, timestamp: 0, extra_data: Default::default(), mix_hash: Default::default(), nonce: 0, base_fee_per_gas: None, } } } impl Header { /// Heavy function that will calculate hash of data and will *not* save the change to metadata. /// Use [`Header::seal`], [`SealedHeader`] and unlock if you need hash to be persistent. pub fn hash_slow(&self) -> H256 { let mut out = BytesMut::new(); self.encode(&mut out); H256::from_slice(keccak256(&out).as_slice()) } /// Calculate hash and seal the Header so that it can't be changed. pub fn seal(self) -> SealedHeader { let hash = self.hash_slow(); SealedHeader { header: self, hash } } fn header_payload_length(&self) -> usize { let mut length = 0; length += self.parent_hash.length(); length += self.ommers_hash.length(); length += self.beneficiary.length(); length += self.state_root.length(); length += self.transactions_root.length(); length += self.receipts_root.length(); length += self.logs_bloom.length(); length += self.difficulty.length(); length += U256::from(self.number).length(); length += U256::from(self.gas_limit).length(); length += U256::from(self.gas_used).length(); length += self.timestamp.length(); length += self.extra_data.length(); length += self.mix_hash.length(); length += H64::from_low_u64_be(self.nonce).length(); length += self.base_fee_per_gas.map(|fee| U256::from(fee).length()).unwrap_or_default(); length } } impl Encodable for Header { fn encode(&self, out: &mut dyn BufMut) { let list_header = reth_rlp::Header { list: true, payload_length: self.header_payload_length() }; list_header.encode(out); self.parent_hash.encode(out); self.ommers_hash.encode(out); self.beneficiary.encode(out); self.state_root.encode(out); self.transactions_root.encode(out); self.receipts_root.encode(out); self.logs_bloom.encode(out); self.difficulty.encode(out); U256::from(self.number).encode(out); U256::from(self.gas_limit).encode(out); U256::from(self.gas_used).encode(out); self.timestamp.encode(out); self.extra_data.encode(out); self.mix_hash.encode(out); H64::from_low_u64_be(self.nonce).encode(out); if let Some(ref base_fee) = self.base_fee_per_gas { U256::from(*base_fee).encode(out); } } fn length(&self) -> usize { let mut length = 0; length += self.header_payload_length(); length += length_of_length(length); length } } impl Decodable for Header { fn decode(buf: &mut &[u8]) -> Result { let rlp_head = reth_rlp::Header::decode(buf)?; if !rlp_head.list { return Err(reth_rlp::DecodeError::UnexpectedString) } let started_len = buf.len(); let mut this = Self { parent_hash: Decodable::decode(buf)?, ommers_hash: Decodable::decode(buf)?, beneficiary: Decodable::decode(buf)?, state_root: Decodable::decode(buf)?, transactions_root: Decodable::decode(buf)?, receipts_root: Decodable::decode(buf)?, logs_bloom: Decodable::decode(buf)?, difficulty: Decodable::decode(buf)?, number: U256::decode(buf)?.as_u64(), gas_limit: U256::decode(buf)?.as_u64(), gas_used: U256::decode(buf)?.as_u64(), timestamp: Decodable::decode(buf)?, extra_data: Decodable::decode(buf)?, mix_hash: Decodable::decode(buf)?, nonce: H64::decode(buf)?.to_low_u64_be(), base_fee_per_gas: None, }; let consumed = started_len - buf.len(); if consumed < rlp_head.payload_length { this.base_fee_per_gas = Some(U256::decode(buf)?.as_u64()); } let consumed = started_len - buf.len(); if consumed != rlp_head.payload_length { return Err(reth_rlp::DecodeError::ListLengthMismatch { expected: rlp_head.payload_length, got: consumed, }) } Ok(this) } } /// A [`Header`] that is sealed at a precalculated hash, use [`SealedHeader::unseal()`] if you want /// to modify header. #[derive(Debug, Clone, PartialEq, Eq, Default, Hash)] pub struct SealedHeader { /// Locked Header fields. header: Header, /// Locked Header hash. hash: BlockHash, } impl AsRef
for SealedHeader { fn as_ref(&self) -> &Header { &self.header } } impl Deref for SealedHeader { type Target = Header; fn deref(&self) -> &Self::Target { &self.header } } impl SealedHeader { /// Construct a new sealed header. /// /// Applicable when hash is known from the database provided it's not corrupted. pub fn new(header: Header, hash: H256) -> Self { Self { header, hash } } /// Extract raw header that can be modified. pub fn unseal(self) -> Header { self.header } /// Return header/block hash. pub fn hash(&self) -> BlockHash { self.hash } } #[cfg(test)] mod tests { use crate::Address; use super::{Decodable, Encodable, Header, H256}; use ethers_core::{ types::Bytes, utils::hex::{self, FromHex}, }; use std::str::FromStr; #[test] // Test vector from: https://eips.ethereum.org/EIPS/eip-2481 fn test_encode_block_header() { let expected = hex::decode("f901f9a00000000000000000000000000000000000000000000000000000000000000000a00000000000000000000000000000000000000000000000000000000000000000940000000000000000000000000000000000000000a00000000000000000000000000000000000000000000000000000000000000000a00000000000000000000000000000000000000000000000000000000000000000a00000000000000000000000000000000000000000000000000000000000000000b90100000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000008208ae820d0582115c8215b3821a0a827788a00000000000000000000000000000000000000000000000000000000000000000880000000000000000").unwrap(); let header = Header { difficulty: 0x8ae_u64.into(), number: 0xd05_u64, gas_limit: 0x115c_u64, gas_used: 0x15b3_u64, timestamp: 0x1a0a_u64, extra_data: Bytes::from_str("7788").unwrap().0, ommers_hash: H256::zero(), state_root: H256::zero(), transactions_root: H256::zero(), receipts_root: H256::zero(), ..Default::default() }; let mut data = vec![]; header.encode(&mut data); assert_eq!(hex::encode(&data), hex::encode(expected)); assert_eq!(header.length(), data.len()); } #[test] // Test vector from: https://github.com/ethereum/tests/blob/f47bbef4da376a49c8fc3166f09ab8a6d182f765/BlockchainTests/ValidBlocks/bcEIP1559/baseFee.json#L15-L36 fn test_eip1559_block_header_hash() { let expected_hash = H256::from_str("6a251c7c3c5dca7b42407a3752ff48f3bbca1fab7f9868371d9918daf1988d1f") .unwrap(); let header = Header { parent_hash: H256::from_str("e0a94a7a3c9617401586b1a27025d2d9671332d22d540e0af72b069170380f2a").unwrap(), ommers_hash: H256::from_str("1dcc4de8dec75d7aab85b567b6ccd41ad312451b948a7413f0a142fd40d49347").unwrap(), beneficiary: Address::from_str("ba5e000000000000000000000000000000000000").unwrap(), state_root: H256::from_str("ec3c94b18b8a1cff7d60f8d258ec723312932928626b4c9355eb4ab3568ec7f7").unwrap(), transactions_root: H256::from_str("50f738580ed699f0469702c7ccc63ed2e51bc034be9479b7bff4e68dee84accf").unwrap(), receipts_root: H256::from_str("29b0562f7140574dd0d50dee8a271b22e1a0a7b78fca58f7c60370d8317ba2a9").unwrap(), logs_bloom: <[u8; 256]>::from_hex("00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000").unwrap().into(), difficulty: 0x020000.into(), number: 0x01_u64, gas_limit: 0x016345785d8a0000_u64, gas_used: 0x015534_u64, timestamp: 0x079e, extra_data: Bytes::from_str("42").unwrap().0, mix_hash: H256::from_str("0000000000000000000000000000000000000000000000000000000000000000").unwrap(), nonce: 0, base_fee_per_gas: Some(0x036b_u64), }; assert_eq!(header.hash_slow(), expected_hash); } #[test] // Test vector from: https://eips.ethereum.org/EIPS/eip-2481 fn test_decode_block_header() { let data = hex::decode("f901f9a00000000000000000000000000000000000000000000000000000000000000000a00000000000000000000000000000000000000000000000000000000000000000940000000000000000000000000000000000000000a00000000000000000000000000000000000000000000000000000000000000000a00000000000000000000000000000000000000000000000000000000000000000a00000000000000000000000000000000000000000000000000000000000000000b90100000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000008208ae820d0582115c8215b3821a0a827788a00000000000000000000000000000000000000000000000000000000000000000880000000000000000").unwrap(); let expected = Header { difficulty: 0x8aeu64.into(), number: 0xd05u64, gas_limit: 0x115cu64, gas_used: 0x15b3u64, timestamp: 0x1a0au64, extra_data: Bytes::from_str("7788").unwrap().0, ommers_hash: H256::zero(), state_root: H256::zero(), transactions_root: H256::zero(), receipts_root: H256::zero(), ..Default::default() }; let header =
::decode(&mut data.as_slice()).unwrap(); assert_eq!(header, expected); } }