rust-bitcoin-unsafe-fast/bitcoin/src/network/params.rs

284 lines
12 KiB
Rust

// SPDX-License-Identifier: CC0-1.0
//! Bitcoin consensus parameters.
//!
//! This module provides a predefined set of parameters for different Bitcoin
//! chains (such as mainnet, testnet, testnet4).
//!
//! # Custom Signets Example
//!
//! In various places in this crate we take `AsRef<Params>` as a parameter, in order to create a
//! custom type that can be used in such places you might want to do the following:
//!
//! ```
//! use bitcoin::network::Params;
//! use bitcoin::{Script, ScriptBuf, Network, Target};
//!
//! const POW_TARGET_SPACING: u64 = 120; // Two minutes.
//!
//! pub struct CustomParams {
//! params: Params,
//! challenge_script: ScriptBuf,
//! }
//!
//! impl CustomParams {
//! /// Constructs a new custom params.
//! pub fn new() -> Self {
//! let mut params = Params::new(Network::Signet);
//! params.pow_target_spacing = POW_TARGET_SPACING;
//!
//! // This would be something real (see BIP-325).
//! let challenge_script = ScriptBuf::new();
//!
//! Self {
//! params,
//! challenge_script,
//! }
//! }
//!
//! /// Returns the custom signet challenge script.
//! pub fn challenge_script(&self) -> &Script { &self.challenge_script }
//! }
//!
//! impl AsRef<Params> for CustomParams {
//! fn as_ref(&self) -> &Params { &self.params }
//! }
//!
//! impl Default for CustomParams {
//! fn default() -> Self { Self::new() }
//! }
//!
//! # { // Just check the code above is usable.
//! # let target = Target::MAX_ATTAINABLE_SIGNET;
//! #
//! # let signet = Params::SIGNET;
//! # let _ = target.difficulty(signet);
//! #
//! # let custom = CustomParams::new();
//! # let _ = custom.challenge_script();
//! # let _ = target.difficulty(custom);
//! # }
//! ```
use units::{BlockHeight, BlockHeightInterval};
use crate::network::Network;
#[cfg(doc)]
use crate::pow::CompactTarget;
use crate::pow::Target;
use crate::TestnetVersion;
/// Parameters that influence chain consensus.
#[non_exhaustive]
#[derive(Debug, Clone)]
pub struct Params {
/// Network for which parameters are valid.
pub network: Network,
/// Time when BIP16 becomes active.
pub bip16_time: u32,
/// Block height at which BIP34 becomes active.
pub bip34_height: BlockHeight,
/// Block height at which BIP65 becomes active.
pub bip65_height: BlockHeight,
/// Block height at which BIP66 becomes active.
pub bip66_height: BlockHeight,
/// Minimum blocks including miner confirmation of the total of 2016 blocks in a retargeting period,
/// (nPowTargetTimespan / nPowTargetSpacing) which is also used for BIP9 deployments.
/// Examples: 1916 for 95%, 1512 for testchains.
pub rule_change_activation_threshold: BlockHeightInterval,
/// Number of blocks with the same set of rules.
pub miner_confirmation_window: BlockHeightInterval,
/// Proof of work limit value. It contains the lowest possible difficulty.
#[deprecated(since = "0.32.0", note = "use `max_attainable_target` instead")]
pub pow_limit: Target,
/// The maximum **attainable** target value for these params.
///
/// Not all target values are attainable because consensus code uses the compact format to
/// represent targets (see [`CompactTarget`]).
///
/// Note that this value differs from Bitcoin Core's powLimit field in that this value is
/// attainable, but Bitcoin Core's is not. Specifically, because targets in Bitcoin are always
/// rounded to the nearest float expressible in "compact form", not all targets are attainable.
/// Still, this should not affect consensus as the only place where the non-compact form of
/// this is used in Bitcoin Core's consensus algorithm is in comparison and there are no
/// compact-expressible values between Bitcoin Core's and the limit expressed here.
pub max_attainable_target: Target,
/// Expected amount of time to mine one block.
pub pow_target_spacing: u64,
/// Difficulty recalculation interval.
pub pow_target_timespan: u32,
/// Determines whether minimal difficulty may be used for blocks or not.
pub allow_min_difficulty_blocks: bool,
/// Determines whether retargeting is disabled for this network or not.
pub no_pow_retargeting: bool,
}
/// The mainnet parameters.
///
/// Use this for a static reference e.g., `&params::MAINNET`.
///
/// For more on static vs const see The Rust Reference [using-statics-or-consts] section.
///
/// [using-statics-or-consts]: <https://doc.rust-lang.org/reference/items/static-items.html#using-statics-or-consts>
pub static MAINNET: Params = Params::MAINNET;
/// The testnet3 parameters.
#[deprecated(since = "0.33.0", note = "use `TESTNET3` instead")]
pub static TESTNET: Params = Params::TESTNET3;
/// The testnet3 parameters.
pub static TESTNET3: Params = Params::TESTNET3;
/// The testnet4 parameters.
pub static TESTNET4: Params = Params::TESTNET4;
/// The signet parameters.
pub static SIGNET: Params = Params::SIGNET;
/// The regtest parameters.
pub static REGTEST: Params = Params::REGTEST;
#[allow(deprecated)] // For `pow_limit`.
impl Params {
/// The mainnet parameters (alias for `Params::MAINNET`).
pub const BITCOIN: Params = Params::MAINNET;
/// The mainnet parameters.
pub const MAINNET: Params = Params {
network: Network::Bitcoin,
bip16_time: 1333238400, // Apr 1 2012
bip34_height: BlockHeight::from_u32(227931), // 000000000000024b89b42a942fe0d9fea3bb44ab7bd1b19115dd6a759c0808b8
bip65_height: BlockHeight::from_u32(388381), // 000000000000000004c2b624ed5d7756c508d90fd0da2c7c679febfa6c4735f0
bip66_height: BlockHeight::from_u32(363725), // 00000000000000000379eaa19dce8c9b722d46ae6a57c2f1a988119488b50931
rule_change_activation_threshold: BlockHeightInterval::from_u32(1916), // 95%
miner_confirmation_window: BlockHeightInterval::from_u32(2016),
pow_limit: Target::MAX_ATTAINABLE_MAINNET,
max_attainable_target: Target::MAX_ATTAINABLE_MAINNET,
pow_target_spacing: 10 * 60, // 10 minutes.
pow_target_timespan: 14 * 24 * 60 * 60, // 2 weeks.
allow_min_difficulty_blocks: false,
no_pow_retargeting: false,
};
/// The testnet3 parameters.
#[deprecated(since = "0.33.0", note = "use `TESTNET3` instead")]
pub const TESTNET: Params = Params {
network: Network::Testnet(TestnetVersion::V3),
bip16_time: 1333238400, // Apr 1 2012
bip34_height: BlockHeight::from_u32(21111), // 0000000023b3a96d3484e5abb3755c413e7d41500f8e2a5c3f0dd01299cd8ef8
bip65_height: BlockHeight::from_u32(581885), // 00000000007f6655f22f98e72ed80d8b06dc761d5da09df0fa1dc4be4f861eb6
bip66_height: BlockHeight::from_u32(330776), // 000000002104c8c45e99a8853285a3b592602a3ccde2b832481da85e9e4ba182
rule_change_activation_threshold: BlockHeightInterval::from_u32(1512), // 75%
miner_confirmation_window: BlockHeightInterval::from_u32(2016),
pow_limit: Target::MAX_ATTAINABLE_TESTNET,
max_attainable_target: Target::MAX_ATTAINABLE_TESTNET,
pow_target_spacing: 10 * 60, // 10 minutes.
pow_target_timespan: 14 * 24 * 60 * 60, // 2 weeks.
allow_min_difficulty_blocks: true,
no_pow_retargeting: false,
};
/// The testnet3 parameters.
pub const TESTNET3: Params = Params {
network: Network::Testnet(TestnetVersion::V3),
bip16_time: 1333238400, // Apr 1 2012
bip34_height: BlockHeight::from_u32(21111), // 0000000023b3a96d3484e5abb3755c413e7d41500f8e2a5c3f0dd01299cd8ef8
bip65_height: BlockHeight::from_u32(581885), // 00000000007f6655f22f98e72ed80d8b06dc761d5da09df0fa1dc4be4f861eb6
bip66_height: BlockHeight::from_u32(330776), // 000000002104c8c45e99a8853285a3b592602a3ccde2b832481da85e9e4ba182
rule_change_activation_threshold: BlockHeightInterval::from_u32(1512), // 75%
miner_confirmation_window: BlockHeightInterval::from_u32(2016),
pow_limit: Target::MAX_ATTAINABLE_TESTNET,
max_attainable_target: Target::MAX_ATTAINABLE_TESTNET,
pow_target_spacing: 10 * 60, // 10 minutes.
pow_target_timespan: 14 * 24 * 60 * 60, // 2 weeks.
allow_min_difficulty_blocks: true,
no_pow_retargeting: false,
};
/// The testnet4 parameters.
pub const TESTNET4: Params = Params {
network: Network::Testnet(TestnetVersion::V4),
bip16_time: 1333238400, // Apr 1 2012
bip34_height: BlockHeight::from_u32(1),
bip65_height: BlockHeight::from_u32(1),
bip66_height: BlockHeight::from_u32(1),
rule_change_activation_threshold: BlockHeightInterval::from_u32(1512), // 75%
miner_confirmation_window: BlockHeightInterval::from_u32(2016),
pow_limit: Target::MAX_ATTAINABLE_TESTNET,
max_attainable_target: Target::MAX_ATTAINABLE_TESTNET,
pow_target_spacing: 10 * 60, // 10 minutes.
pow_target_timespan: 14 * 24 * 60 * 60, // 2 weeks.
allow_min_difficulty_blocks: true,
no_pow_retargeting: false,
};
/// The signet parameters.
pub const SIGNET: Params = Params {
network: Network::Signet,
bip16_time: 1333238400, // Apr 1 2012
bip34_height: BlockHeight::from_u32(1),
bip65_height: BlockHeight::from_u32(1),
bip66_height: BlockHeight::from_u32(1),
rule_change_activation_threshold: BlockHeightInterval::from_u32(1916), // 95%
miner_confirmation_window: BlockHeightInterval::from_u32(2016),
pow_limit: Target::MAX_ATTAINABLE_SIGNET,
max_attainable_target: Target::MAX_ATTAINABLE_SIGNET,
pow_target_spacing: 10 * 60, // 10 minutes.
pow_target_timespan: 14 * 24 * 60 * 60, // 2 weeks.
allow_min_difficulty_blocks: false,
no_pow_retargeting: false,
};
/// The regtest parameters.
pub const REGTEST: Params = Params {
network: Network::Regtest,
bip16_time: 1333238400, // Apr 1 2012
bip34_height: BlockHeight::from_u32(100000000), // not activated on regtest
bip65_height: BlockHeight::from_u32(1351),
bip66_height: BlockHeight::from_u32(1251), // used only in rpc tests
rule_change_activation_threshold: BlockHeightInterval::from_u32(108), // 75%
miner_confirmation_window: BlockHeightInterval::from_u32(144),
pow_limit: Target::MAX_ATTAINABLE_REGTEST,
max_attainable_target: Target::MAX_ATTAINABLE_REGTEST,
pow_target_spacing: 10 * 60, // 10 minutes.
pow_target_timespan: 14 * 24 * 60 * 60, // 2 weeks.
allow_min_difficulty_blocks: true,
no_pow_retargeting: true,
};
/// Creates parameters set for the given network.
pub const fn new(network: Network) -> Self {
match network {
Network::Bitcoin => Params::MAINNET,
Network::Testnet(TestnetVersion::V3) => Params::TESTNET3,
Network::Testnet(TestnetVersion::V4) => Params::TESTNET4,
Network::Signet => Params::SIGNET,
Network::Regtest => Params::REGTEST,
}
}
/// Calculates the number of blocks between difficulty adjustments.
pub fn difficulty_adjustment_interval(&self) -> u64 {
u64::from(self.pow_target_timespan) / self.pow_target_spacing
}
}
impl From<Network> for Params {
fn from(value: Network) -> Self { Self::new(value) }
}
impl From<&Network> for Params {
fn from(value: &Network) -> Self { Self::new(*value) }
}
impl From<Network> for &'static Params {
fn from(value: Network) -> Self { value.params() }
}
impl From<&Network> for &'static Params {
fn from(value: &Network) -> Self { value.params() }
}
impl AsRef<Params> for Params {
fn as_ref(&self) -> &Params { self }
}
impl AsRef<Params> for Network {
fn as_ref(&self) -> &Params { Self::params(*self) }
}