use crate::prelude::*;
use core::fmt;
use crate::util;
use crate::util::Error::{BlockBadTarget, BlockBadProofOfWork};
use crate::util::hash::bitcoin_merkle_root;
use crate::hashes::{Hash, HashEngine};
use crate::hash_types::{Wtxid, BlockHash, TxMerkleNode, WitnessMerkleNode, WitnessCommitment};
use crate::util::uint::Uint256;
use crate::consensus::encode::Encodable;
use crate::network::constants::Network;
use crate::blockdata::transaction::Transaction;
use crate::blockdata::constants::{max_target, WITNESS_SCALE_FACTOR};
use crate::blockdata::script;
use crate::VarInt;
use crate::internal_macros::impl_consensus_encoding;
#[derive(Copy, PartialEq, Eq, Clone, Debug, PartialOrd, Ord, Hash)]
#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
#[cfg_attr(feature = "serde", serde(crate = "actual_serde"))]
pub struct BlockHeader {
pub version: i32,
pub prev_blockhash: BlockHash,
pub merkle_root: TxMerkleNode,
pub time: u32,
pub bits: u32,
pub nonce: u32,
}
impl_consensus_encoding!(BlockHeader, version, prev_blockhash, merkle_root, time, bits, nonce);
impl BlockHeader {
pub fn block_hash(&self) -> BlockHash {
let mut engine = BlockHash::engine();
self.consensus_encode(&mut engine).expect("engines don't error");
BlockHash::from_engine(engine)
}
pub fn target(&self) -> Uint256 {
Self::u256_from_compact_target(self.bits)
}
pub fn u256_from_compact_target(bits: u32) -> Uint256 {
let (mant, expt) = {
let unshifted_expt = bits >> 24;
if unshifted_expt <= 3 {
((bits & 0xFFFFFF) >> (8 * (3 - unshifted_expt as usize)), 0)
} else {
(bits & 0xFFFFFF, 8 * ((bits >> 24) - 3))
}
};
if mant > 0x7FFFFF {
Default::default()
} else {
Uint256::from_u64(mant as u64).unwrap() << (expt as usize)
}
}
pub fn compact_target_from_u256(value: &Uint256) -> u32 {
let mut size = (value.bits() + 7) / 8;
let mut compact = if size <= 3 {
(value.low_u64() << (8 * (3 - size))) as u32
} else {
let bn = *value >> (8 * (size - 3));
bn.low_u32()
};
if (compact & 0x00800000) != 0 {
compact >>= 8;
size += 1;
}
compact | (size << 24) as u32
}
pub fn difficulty(&self, network: Network) -> u64 {
(max_target(network) / self.target()).low_u64()
}
pub fn validate_pow(&self, required_target: &Uint256) -> Result<BlockHash, util::Error> {
let target = &self.target();
if target != required_target {
return Err(BlockBadTarget);
}
let block_hash = self.block_hash();
let mut ret = [0u64; 4];
util::endian::bytes_to_u64_slice_le(block_hash.as_inner(), &mut ret);
let hash = &Uint256(ret);
if hash <= target { Ok(block_hash) } else { Err(BlockBadProofOfWork) }
}
pub fn work(&self) -> Uint256 {
let mut ret = !self.target();
let mut ret1 = self.target();
ret1.increment();
ret = ret / ret1;
ret.increment();
ret
}
}
#[derive(PartialEq, Eq, Clone, Debug)]
#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
#[cfg_attr(feature = "serde", serde(crate = "actual_serde"))]
pub struct Block {
pub header: BlockHeader,
pub txdata: Vec<Transaction>
}
impl_consensus_encoding!(Block, header, txdata);
impl Block {
pub fn block_hash(&self) -> BlockHash {
self.header.block_hash()
}
pub fn check_merkle_root(&self) -> bool {
match self.compute_merkle_root() {
Some(merkle_root) => self.header.merkle_root == merkle_root,
None => false,
}
}
pub fn check_witness_commitment(&self) -> bool {
const MAGIC: [u8; 6] = [0x6a, 0x24, 0xaa, 0x21, 0xa9, 0xed];
if self.txdata.iter().all(|t| t.input.iter().all(|i| i.witness.is_empty())) {
return true;
}
if self.txdata.is_empty() {
return false;
}
let coinbase = &self.txdata[0];
if !coinbase.is_coin_base() {
return false;
}
if let Some(pos) = coinbase.output.iter()
.rposition(|o| o.script_pubkey.len () >= 38 && o.script_pubkey[0..6] == MAGIC)
{
let commitment = WitnessCommitment::from_slice(&coinbase.output[pos].script_pubkey.as_bytes()[6..38]).unwrap();
let witness_vec: Vec<_> = coinbase.input[0].witness.iter().collect();
if witness_vec.len() == 1 && witness_vec[0].len() == 32 {
if let Some(witness_root) = self.witness_root() {
return commitment == Self::compute_witness_commitment(&witness_root, witness_vec[0]);
}
}
}
false
}
pub fn compute_merkle_root(&self) -> Option<TxMerkleNode> {
let hashes = self.txdata.iter().map(|obj| obj.txid().as_hash());
bitcoin_merkle_root(hashes).map(|h| h.into())
}
#[deprecated(since = "0.28.0", note = "Please use `block::compute_merkle_root` instead.")]
pub fn merkle_root(&self) -> Option<TxMerkleNode> {
self.compute_merkle_root()
}
pub fn compute_witness_commitment(witness_root: &WitnessMerkleNode, witness_reserved_value: &[u8]) -> WitnessCommitment {
let mut encoder = WitnessCommitment::engine();
witness_root.consensus_encode(&mut encoder).expect("engines don't error");
encoder.input(witness_reserved_value);
WitnessCommitment::from_engine(encoder)
}
pub fn witness_root(&self) -> Option<WitnessMerkleNode> {
let hashes = self.txdata.iter().enumerate().map(|(i, t)| {
if i == 0 {
Wtxid::all_zeros().as_hash()
} else {
t.wtxid().as_hash()
}
});
bitcoin_merkle_root(hashes).map(|h| h.into())
}
fn base_size(&self) -> usize {
80 + VarInt(self.txdata.len() as u64).len()
}
#[deprecated(since = "0.28.0", note = "Please use `block::size` instead.")]
pub fn get_size(&self) -> usize {
self.size()
}
pub fn size(&self) -> usize {
let txs_size: usize = self.txdata.iter().map(Transaction::size).sum();
self.base_size() + txs_size
}
#[deprecated(since = "0.28.0", note = "Please use `transaction::strippedsize` instead.")]
pub fn get_strippedsize(&self) -> usize {
self.strippedsize()
}
pub fn strippedsize(&self) -> usize {
let txs_size: usize = self.txdata.iter().map(Transaction::strippedsize).sum();
self.base_size() + txs_size
}
#[deprecated(since = "0.28.0", note = "Please use `transaction::weight` instead.")]
pub fn get_weight(&self) -> usize {
self.weight()
}
pub fn weight(&self) -> usize {
let base_weight = WITNESS_SCALE_FACTOR * self.base_size();
let txs_weight: usize = self.txdata.iter().map(Transaction::weight).sum();
base_weight + txs_weight
}
pub fn coinbase(&self) -> Option<&Transaction> {
self.txdata.first()
}
pub fn bip34_block_height(&self) -> Result<u64, Bip34Error> {
if self.header.version < 2 {
return Err(Bip34Error::Unsupported);
}
let cb = self.coinbase().ok_or(Bip34Error::NotPresent)?;
let input = cb.input.first().ok_or(Bip34Error::NotPresent)?;
let push = input.script_sig.instructions_minimal().next().ok_or(Bip34Error::NotPresent)?;
match push.map_err(|_| Bip34Error::NotPresent)? {
script::Instruction::PushBytes(b) if b.len() <= 8 => {
let mut full = [0; 8];
full[0..b.len()].copy_from_slice(b);
Ok(util::endian::slice_to_u64_le(&full))
}
script::Instruction::PushBytes(b) if b.len() > 8 => {
Err(Bip34Error::UnexpectedPush(b.to_vec()))
}
_ => Err(Bip34Error::NotPresent),
}
}
}
#[derive(Debug, Clone, PartialEq, Eq)]
#[non_exhaustive]
pub enum Bip34Error {
Unsupported,
NotPresent,
UnexpectedPush(Vec<u8>),
}
impl fmt::Display for Bip34Error {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
match *self {
Bip34Error::Unsupported => write!(f, "block doesn't support BIP34"),
Bip34Error::NotPresent => write!(f, "BIP34 push not present in block's coinbase"),
Bip34Error::UnexpectedPush(ref p) => {
write!(f, "unexpected byte push of > 8 bytes: {:?}", p)
}
}
}
}
#[cfg(feature = "std")]
#[cfg_attr(docsrs, doc(cfg(feature = "std")))]
impl std::error::Error for Bip34Error {
fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
use self::Bip34Error::*;
match self {
Unsupported | NotPresent | UnexpectedPush(_) => None,
}
}
}
#[cfg(test)]
mod tests {
use crate::hashes::hex::FromHex;
use crate::blockdata::block::{Block, BlockHeader};
use crate::consensus::encode::{deserialize, serialize};
use crate::util::uint::Uint256;
use crate::util::Error::{BlockBadTarget, BlockBadProofOfWork};
use crate::network::constants::Network;
#[test]
fn test_coinbase_and_bip34() {
let block_hex = "0200000035ab154183570282ce9afc0b494c9fc6a3cfea05aa8c1add2ecc56490000000038ba3d78e4500a5a7570dbe61960398add4410d278b21cd9708e6d9743f374d544fc055227f1001c29c1ea3b0101000000010000000000000000000000000000000000000000000000000000000000000000ffffffff3703a08601000427f1001c046a510100522cfabe6d6d0000000000000000000068692066726f6d20706f6f6c7365727665726aac1eeeed88ffffffff0100f2052a010000001976a914912e2b234f941f30b18afbb4fa46171214bf66c888ac00000000";
let block: Block = deserialize(&Vec::<u8>::from_hex(block_hex).unwrap()).unwrap();
let cb_txid = "9ba1552009af3956649bf0cbf8d751aa12aee992e16d1c3965bf7eee76d405fc";
assert_eq!(block.coinbase().unwrap().txid().to_string(), cb_txid);
assert_eq!(block.bip34_block_height(), Ok(100_000));
let bad_hex = "0200000035ab154183570282ce9afc0b494c9fc6a3cfea05aa8c1add2ecc56490000000038ba3d78e4500a5a7570dbe61960398add4410d278b21cd9708e6d9743f374d544fc055227f1001c29c1ea3b0101000000010000000000000000000000000000000000000000000000000000000000000000ffffffff3d09a08601112233445566000427f1001c046a510100522cfabe6d6d0000000000000000000068692066726f6d20706f6f6c7365727665726aac1eeeed88ffffffff0100f2052a010000001976a914912e2b234f941f30b18afbb4fa46171214bf66c888ac00000000";
let bad: Block = deserialize(&Vec::<u8>::from_hex(bad_hex).unwrap()).unwrap();
let push = Vec::<u8>::from_hex("a08601112233445566").unwrap();
assert_eq!(bad.bip34_block_height(), Err(super::Bip34Error::UnexpectedPush(push)));
}
#[test]
fn block_test() {
let some_block = Vec::from_hex("7000000054e62863a89f1c737a8c9647c3843d16bcfd81c9b0048653b459df0200000000755988c47b18539187e9d050453781266ddd193820e94c72eff0b7562185f52578154053ab1d031c18d135000101000000010000000000000000000000000000000000000000000000000000000000000000ffffffff2602204e062f503253482f04df15405308f800029f4b0000000d2f7374726174756d506f6f6c2f00000000010000a7340b0000001976a9141aad02bd83c154bf91c9a51e70c5b28dc3720b8188ac00000000").unwrap();
let cutoff_block = Vec::from_hex("7000000054e62863a89f1c737a8c9647c3843d16bcfd81c9b0048653b459df0200000000755988c47b18539187e9d050453781266ddd193820e94c72eff0b7562185f52578154053ab1d031c18d135000101000000010000000000000000000000000000000000000000000000000000000000000000ffffffff2602204e062f503253482f04df15405308f800029f4b0000000d2f7374726174756d506f6f6c2f00000000010000a7340b0000001976a9141aad02bd83c154bf91c9a51e70c5b28dc3720b8188ac").unwrap();
let prevhash = Vec::from_hex("54e62863a89f1c737a8c9647c3843d16bcfd81c9b0048653b459df0200000000").unwrap();
let merkle = Vec::from_hex("755988c47b18539187e9d050453781266ddd193820e94c72eff0b7562185f525").unwrap();
let work = Uint256([0x5228d4dedau64, 0, 0, 0]);
let decode: Result<Block, _> = deserialize(&some_block);
let bad_decode: Result<Block, _> = deserialize(&cutoff_block);
assert!(decode.is_ok());
assert!(bad_decode.is_err());
let real_decode = decode.unwrap();
assert_eq!(real_decode.header.version, 112);
assert_eq!(serialize(&real_decode.header.prev_blockhash), prevhash);
assert_eq!(real_decode.header.merkle_root, real_decode.compute_merkle_root().unwrap());
assert_eq!(serialize(&real_decode.header.merkle_root), merkle);
assert_eq!(real_decode.header.time, 1396708728);
assert_eq!(real_decode.header.bits, 0x1c031dab);
assert_eq!(real_decode.header.nonce, 3526936);
assert_eq!(real_decode.header.work(), work);
assert_eq!(real_decode.header.validate_pow(&real_decode.header.target()).unwrap(), real_decode.block_hash());
assert_eq!(real_decode.header.difficulty(Network::Groestlcoin), 82);
assert_eq!(real_decode.size(), some_block.len());
assert_eq!(real_decode.strippedsize(), some_block.len());
assert_eq!(real_decode.weight(), some_block.len() * 4);
assert!(real_decode.check_witness_commitment());
assert_eq!(serialize(&real_decode), some_block);
}
#[test] #[ignore]
fn segwit_block_test() {
let segwit_block = include_bytes!("../../test_data/testnet_block_000000000000045e0b1660b6445b5e5c5ab63c9a4f956be7e1e69be04fa4497b.raw").to_vec();
let decode: Result<Block, _> = deserialize(&segwit_block);
let prevhash = Vec::from_hex("51f4bcc013edd897566497e64c35735d4320f52e4c64b59a4007000000000000").unwrap();
let merkle = Vec::from_hex("163c9ba874a3e94426b379e769bdfd4df93117114c14d14111dd7f1aa0a375c9").unwrap();
let work = Uint256([0x6b9fa222841d9u64, 0, 0, 0]);
assert!(decode.is_ok());
let real_decode = decode.unwrap();
assert_eq!(real_decode.header.version, 0x20000000); assert_eq!(serialize(&real_decode.header.prev_blockhash), prevhash);
assert_eq!(serialize(&real_decode.header.merkle_root), merkle);
assert_eq!(real_decode.header.merkle_root, real_decode.compute_merkle_root().unwrap());
assert_eq!(real_decode.header.time, 1644213054);
assert_eq!(real_decode.header.bits, 0x1a260eff);
assert_eq!(real_decode.header.nonce, 121839433);
assert_eq!(real_decode.header.work(), work);
assert_eq!(real_decode.header.validate_pow(&real_decode.header.target()).unwrap(), real_decode.block_hash());
assert_eq!(real_decode.header.difficulty(Network::Testnet), 440819);
assert_eq!(real_decode.size(), segwit_block.len());
assert_eq!(real_decode.strippedsize(), 385);
assert_eq!(real_decode.weight(), 1685);
assert!(real_decode.check_witness_commitment());
assert_eq!(serialize(&real_decode), segwit_block);
}
#[test]
fn block_version_test() {
let block = Vec::from_hex("ffffff7f0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000").unwrap();
let decode: Result<Block, _> = deserialize(&block);
assert!(decode.is_ok());
let real_decode = decode.unwrap();
assert_eq!(real_decode.header.version, 2147483647);
let block2 = Vec::from_hex("000000800000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000").unwrap();
let decode2: Result<Block, _> = deserialize(&block2);
assert!(decode2.is_ok());
let real_decode2 = decode2.unwrap();
assert_eq!(real_decode2.header.version, -2147483648);
}
#[test]
fn validate_pow_test() {
let some_header = Vec::from_hex("7000000054e62863a89f1c737a8c9647c3843d16bcfd81c9b0048653b459df0200000000755988c47b18539187e9d050453781266ddd193820e94c72eff0b7562185f52578154053ab1d031c18d13500").unwrap();
let some_header: BlockHeader = deserialize(&some_header).expect("Can't deserialize correct block header");
assert_eq!(some_header.validate_pow(&some_header.target()).unwrap(), some_header.block_hash());
match some_header.validate_pow(&Uint256::default()) {
Err(BlockBadTarget) => (),
_ => panic!("unexpected result from validate_pow"),
}
let mut invalid_header: BlockHeader = some_header;
invalid_header.version += 1;
match invalid_header.validate_pow(&invalid_header.target()) {
Err(BlockBadProofOfWork) => (),
_ => panic!("unexpected result from validate_pow"),
}
}
#[test]
fn compact_roundrtip_test() {
let some_header = Vec::from_hex("010000004ddccd549d28f385ab457e98d1b11ce80bfea2c5ab93015ade4973e400000000bf4473e53794beae34e64fccc471dace6ae544180816f89591894e0f417a914cd74d6e49ffff001d323b3a7b").unwrap();
let header: BlockHeader = deserialize(&some_header).expect("Can't deserialize correct block header");
assert_eq!(header.bits, BlockHeader::compact_target_from_u256(&header.target()));
}
}
#[cfg(bench)]
mod benches {
use super::Block;
use crate::EmptyWrite;
use crate::consensus::{deserialize, Encodable, Decodable};
use test::{black_box, Bencher};
#[bench]
pub fn bench_stream_reader(bh: &mut Bencher) {
let big_block = include_bytes!("../../test_data/mainnet_block_000000000000000000000c835b2adcaedc20fdf6ee440009c249452c726dafae.raw");
assert_eq!(big_block.len(), 1_381_836);
let big_block = black_box(big_block);
bh.iter(|| {
let mut reader = &big_block[..];
let block = Block::consensus_decode(&mut reader).unwrap();
black_box(&block);
});
}
#[bench]
pub fn bench_block_serialize(bh: &mut Bencher) {
let raw_block = include_bytes!("../../test_data/mainnet_block_000000000000000000000c835b2adcaedc20fdf6ee440009c249452c726dafae.raw");
let block: Block = deserialize(&raw_block[..]).unwrap();
let mut data = Vec::with_capacity(raw_block.len());
bh.iter(|| {
let result = block.consensus_encode(&mut data);
black_box(&result);
data.clear();
});
}
#[bench]
pub fn bench_block_serialize_logic(bh: &mut Bencher) {
let raw_block = include_bytes!("../../test_data/mainnet_block_000000000000000000000c835b2adcaedc20fdf6ee440009c249452c726dafae.raw");
let block: Block = deserialize(&raw_block[..]).unwrap();
bh.iter(|| {
let size = block.consensus_encode(&mut EmptyWrite);
black_box(&size);
});
}
#[bench]
pub fn bench_block_deserialize(bh: &mut Bencher) {
let raw_block = include_bytes!("../../test_data/mainnet_block_000000000000000000000c835b2adcaedc20fdf6ee440009c249452c726dafae.raw");
bh.iter(|| {
let block: Block = deserialize(&raw_block[..]).unwrap();
black_box(&block);
});
}
}