zebra/zebra-chain/src/transparent.rs

433 lines
14 KiB
Rust

//! Transparent-related (Bitcoin-inherited) functionality.
use std::{collections::HashMap, fmt, iter};
use crate::{
amount::{Amount, NonNegative},
block,
parameters::Network,
primitives::zcash_primitives,
transaction,
};
mod address;
mod keys;
mod opcodes;
mod script;
mod serialize;
mod utxo;
pub use address::Address;
pub use script::Script;
pub use serialize::{GENESIS_COINBASE_DATA, MAX_COINBASE_DATA_LEN, MAX_COINBASE_HEIGHT_DATA_LEN};
pub use utxo::{
new_ordered_outputs, new_outputs, outputs_from_utxos, utxos_from_ordered_utxos,
CoinbaseSpendRestriction, OrderedUtxo, Utxo,
};
#[cfg(any(test, feature = "proptest-impl"))]
pub use utxo::{
new_ordered_outputs_with_height, new_outputs_with_height, new_transaction_ordered_outputs,
};
#[cfg(any(test, feature = "proptest-impl"))]
mod arbitrary;
#[cfg(test)]
mod tests;
#[cfg(any(test, feature = "proptest-impl"))]
use proptest_derive::Arbitrary;
/// The maturity threshold for transparent coinbase outputs.
///
/// "A transaction MUST NOT spend a transparent output of a coinbase transaction
/// from a block less than 100 blocks prior to the spend. Note that transparent
/// outputs of coinbase transactions include Founders' Reward outputs and
/// transparent Funding Stream outputs."
/// [7.1](https://zips.z.cash/protocol/nu5.pdf#txnencodingandconsensus)
//
// TODO: change type to HeightDiff
pub const MIN_TRANSPARENT_COINBASE_MATURITY: u32 = 100;
/// Extra coinbase data that identifies some coinbase transactions generated by Zebra.
/// <https://emojipedia.org/zebra/>
//
// # Note
//
// rust-analyzer will crash in some editors when moving over an actual Zebra emoji,
// so we encode it here. This is a known issue in emacs-lsp and other lsp implementations:
// - https://github.com/rust-lang/rust-analyzer/issues/9121
// - https://github.com/emacs-lsp/lsp-mode/issues/2080
// - https://github.com/rust-lang/rust-analyzer/issues/13709
pub const EXTRA_ZEBRA_COINBASE_DATA: &str = "z\u{1F993}";
/// Arbitrary data inserted by miners into a coinbase transaction.
//
// TODO: rename to ExtraCoinbaseData, because height is also part of the coinbase data?
#[derive(Clone, Eq, PartialEq)]
#[cfg_attr(
any(test, feature = "proptest-impl", feature = "elasticsearch"),
derive(Serialize)
)]
pub struct CoinbaseData(
/// Invariant: this vec, together with the coinbase height, must be less than
/// 100 bytes. We enforce this by only constructing CoinbaseData fields by
/// parsing blocks with 100-byte data fields, and checking newly created
/// CoinbaseData lengths in the transaction builder.
pub(super) Vec<u8>,
);
#[cfg(any(test, feature = "proptest-impl"))]
impl CoinbaseData {
/// Create a new `CoinbaseData` containing `data`.
///
/// Only for use in tests.
pub fn new(data: Vec<u8>) -> CoinbaseData {
CoinbaseData(data)
}
}
impl AsRef<[u8]> for CoinbaseData {
fn as_ref(&self) -> &[u8] {
self.0.as_ref()
}
}
impl std::fmt::Debug for CoinbaseData {
#[allow(clippy::unwrap_in_result)]
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
let escaped = String::from_utf8(
self.0
.iter()
.cloned()
.flat_map(std::ascii::escape_default)
.collect(),
)
.expect("ascii::escape_default produces utf8");
f.debug_tuple("CoinbaseData").field(&escaped).finish()
}
}
/// OutPoint
///
/// A particular transaction output reference.
#[derive(Copy, Clone, Debug, Eq, PartialEq, Hash)]
#[cfg_attr(any(test, feature = "proptest-impl"), derive(Arbitrary))]
#[cfg_attr(
any(test, feature = "proptest-impl", feature = "elasticsearch"),
derive(Serialize)
)]
pub struct OutPoint {
/// References the transaction that contains the UTXO being spent.
///
/// # Correctness
///
/// Consensus-critical serialization uses
/// [`ZcashSerialize`](crate::serialization::ZcashSerialize).
/// [`serde`]-based hex serialization must only be used for testing.
#[cfg_attr(any(test, feature = "proptest-impl"), serde(with = "hex"))]
pub hash: transaction::Hash,
/// Identifies which UTXO from that transaction is referenced; the
/// first output is 0, etc.
pub index: u32,
}
impl OutPoint {
/// Returns a new [`OutPoint`] from an in-memory output `index`.
///
/// # Panics
///
/// If `index` doesn't fit in a [`u32`].
pub fn from_usize(hash: transaction::Hash, index: usize) -> OutPoint {
OutPoint {
hash,
index: index
.try_into()
.expect("valid in-memory output indexes fit in a u32"),
}
}
}
/// A transparent input to a transaction.
#[derive(Clone, Debug, Eq, PartialEq)]
#[cfg_attr(
any(test, feature = "proptest-impl", feature = "elasticsearch"),
derive(Serialize)
)]
pub enum Input {
/// A reference to an output of a previous transaction.
PrevOut {
/// The previous output transaction reference.
outpoint: OutPoint,
/// The script that authorizes spending `outpoint`.
unlock_script: Script,
/// The sequence number for the output.
sequence: u32,
},
/// New coins created by the block reward.
Coinbase {
/// The height of this block.
height: block::Height,
/// Free data inserted by miners after the block height.
data: CoinbaseData,
/// The sequence number for the output.
sequence: u32,
},
}
impl fmt::Display for Input {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
match self {
Input::PrevOut {
outpoint,
unlock_script,
..
} => {
let mut fmter = f.debug_struct("transparent::Input::PrevOut");
fmter.field("unlock_script_len", &unlock_script.as_raw_bytes().len());
fmter.field("outpoint", outpoint);
fmter.finish()
}
Input::Coinbase { height, data, .. } => {
let mut fmter = f.debug_struct("transparent::Input::Coinbase");
fmter.field("height", height);
fmter.field("data_len", &data.0.len());
fmter.finish()
}
}
}
}
impl Input {
/// Returns a new coinbase input for `height` with optional `data` and `sequence`.
///
/// # Consensus
///
/// The combined serialized size of `height` and `data` can be at most 100 bytes.
///
/// > A coinbase transaction script MUST have length in {2 .. 100} bytes.
///
/// <https://zips.z.cash/protocol/protocol.pdf#txnconsensus>
///
/// # Panics
///
/// If the coinbase data is greater than [`MAX_COINBASE_DATA_LEN`].
#[cfg(feature = "getblocktemplate-rpcs")]
pub fn new_coinbase(
height: block::Height,
data: Option<Vec<u8>>,
sequence: Option<u32>,
) -> Input {
// "No extra coinbase data" is the default.
let data = data.unwrap_or_default();
let height_size = height.coinbase_zcash_serialized_size();
assert!(
data.len() + height_size <= MAX_COINBASE_DATA_LEN,
"invalid coinbase data: extra data {} bytes + height {height_size} bytes \
must be {} or less",
data.len(),
MAX_COINBASE_DATA_LEN,
);
Input::Coinbase {
height,
data: CoinbaseData(data),
// If the caller does not specify the sequence number,
// use a sequence number that activates the LockTime.
sequence: sequence.unwrap_or(0),
}
}
/// Returns the extra coinbase data in this input, if it is an [`Input::Coinbase`].
pub fn extra_coinbase_data(&self) -> Option<&CoinbaseData> {
match self {
Input::PrevOut { .. } => None,
Input::Coinbase { data, .. } => Some(data),
}
}
/// Returns the input's sequence number.
pub fn sequence(&self) -> u32 {
match self {
Input::PrevOut { sequence, .. } | Input::Coinbase { sequence, .. } => *sequence,
}
}
/// Sets the input's sequence number.
///
/// Only for use in tests.
#[cfg(any(test, feature = "proptest-impl"))]
pub fn set_sequence(&mut self, new_sequence: u32) {
match self {
Input::PrevOut { sequence, .. } | Input::Coinbase { sequence, .. } => {
*sequence = new_sequence
}
}
}
/// If this is a [`Input::PrevOut`] input, returns this input's
/// [`OutPoint`]. Otherwise, returns `None`.
pub fn outpoint(&self) -> Option<OutPoint> {
if let Input::PrevOut { outpoint, .. } = self {
Some(*outpoint)
} else {
None
}
}
/// Set this input's [`OutPoint`].
///
/// Should only be called on [`Input::PrevOut`] inputs.
///
/// # Panics
///
/// If `self` is a coinbase input.
#[cfg(any(test, feature = "proptest-impl"))]
pub fn set_outpoint(&mut self, new_outpoint: OutPoint) {
if let Input::PrevOut {
ref mut outpoint, ..
} = self
{
*outpoint = new_outpoint;
} else {
unreachable!("unexpected variant: Coinbase Inputs do not have OutPoints");
}
}
/// Get the value spent by this input, by looking up its [`OutPoint`] in `outputs`.
/// See [`Self::value`] for details.
///
/// # Panics
///
/// If the provided [`Output`]s don't have this input's [`OutPoint`].
pub(crate) fn value_from_outputs(
&self,
outputs: &HashMap<OutPoint, Output>,
) -> Amount<NonNegative> {
match self {
Input::PrevOut { outpoint, .. } => {
outputs
.get(outpoint)
.unwrap_or_else(|| {
panic!(
"provided Outputs (length {:?}) don't have spent {:?}",
outputs.len(),
outpoint
)
})
.value
}
Input::Coinbase { .. } => Amount::zero(),
}
}
/// Get the value spent by this input, by looking up its [`OutPoint`] in
/// [`Utxo`]s.
///
/// This amount is added to the transaction value pool by this input.
///
/// # Panics
///
/// If the provided [`Utxo`]s don't have this input's [`OutPoint`].
pub fn value(&self, utxos: &HashMap<OutPoint, utxo::Utxo>) -> Amount<NonNegative> {
if let Some(outpoint) = self.outpoint() {
// look up the specific Output and convert it to the expected format
let output = utxos
.get(&outpoint)
.expect("provided Utxos don't have spent OutPoint")
.output
.clone();
self.value_from_outputs(&iter::once((outpoint, output)).collect())
} else {
// coinbase inputs don't need any UTXOs
self.value_from_outputs(&HashMap::new())
}
}
/// Get the value spent by this input, by looking up its [`OutPoint`] in
/// [`OrderedUtxo`]s.
///
/// See [`Self::value`] for details.
///
/// # Panics
///
/// If the provided [`OrderedUtxo`]s don't have this input's [`OutPoint`].
pub fn value_from_ordered_utxos(
&self,
ordered_utxos: &HashMap<OutPoint, utxo::OrderedUtxo>,
) -> Amount<NonNegative> {
if let Some(outpoint) = self.outpoint() {
// look up the specific Output and convert it to the expected format
let output = ordered_utxos
.get(&outpoint)
.expect("provided Utxos don't have spent OutPoint")
.utxo
.output
.clone();
self.value_from_outputs(&iter::once((outpoint, output)).collect())
} else {
// coinbase inputs don't need any UTXOs
self.value_from_outputs(&HashMap::new())
}
}
}
/// A transparent output from a transaction.
///
/// The most fundamental building block of a transaction is a
/// transaction output -- the ZEC you own in your "wallet" is in
/// fact a subset of unspent transaction outputs (or "UTXO"s) of the
/// global UTXO set.
///
/// UTXOs are indivisible, discrete units of value which can only be
/// consumed in their entirety. Thus, if I want to send you 1 ZEC and
/// I only own one UTXO worth 2 ZEC, I would construct a transaction
/// that spends my UTXO and sends 1 ZEC to you and 1 ZEC back to me
/// (just like receiving change).
#[derive(Clone, Debug, Eq, PartialEq, Hash)]
#[cfg_attr(any(test, feature = "proptest-impl"), derive(Arbitrary, Deserialize))]
#[cfg_attr(
any(test, feature = "proptest-impl", feature = "elasticsearch"),
derive(Serialize)
)]
pub struct Output {
/// Transaction value.
// At https://en.bitcoin.it/wiki/Protocol_documentation#tx, this is an i64.
pub value: Amount<NonNegative>,
/// The lock script defines the conditions under which this output can be spent.
pub lock_script: Script,
}
impl Output {
/// Returns a new coinbase output that pays `amount` using `lock_script`.
#[cfg(feature = "getblocktemplate-rpcs")]
pub fn new_coinbase(amount: Amount<NonNegative>, lock_script: Script) -> Output {
Output {
value: amount,
lock_script,
}
}
/// Get the value contained in this output.
/// This amount is subtracted from the transaction value pool by this output.
pub fn value(&self) -> Amount<NonNegative> {
self.value
}
/// Return the destination address from a transparent output.
///
/// Returns None if the address type is not valid or unrecognized.
pub fn address(&self, network: &Network) -> Option<Address> {
zcash_primitives::transparent_output_address(self, network)
}
}