use bitcoin::secp256k1::key::PublicKey;
use ln::features::InitFeatures;
+use ln::msgs::DecodeError;
+use util::ser::{Readable, Writeable, Writer};
use std::convert::TryFrom;
+use std::io::Read;
+use core::num::NonZeroU8;
/// A script pubkey for shutting down a channel as defined by [BOLT #2].
///
/// [BOLT #2]: https://github.com/lightningnetwork/lightning-rfc/blob/master/02-peer-protocol.md
+#[derive(Clone)]
pub struct ShutdownScript(ShutdownScriptImpl);
/// An error occurring when converting from [`Script`] to [`ShutdownScript`].
#[derive(Debug)]
pub struct InvalidShutdownScript(Script);
+#[derive(Clone)]
enum ShutdownScriptImpl {
/// [`PublicKey`] used to form a P2WPKH script pubkey. Used to support backward-compatible
/// serialization.
Bolt2(Script),
}
+impl Writeable for ShutdownScript {
+ fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
+ self.0.write(w)
+ }
+
+ fn serialized_length(&self) -> usize {
+ self.0.serialized_length()
+ }
+}
+
+impl Readable for ShutdownScript {
+ fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
+ Ok(ShutdownScript(ShutdownScriptImpl::read(r)?))
+ }
+}
+
+impl_writeable_tlv_based_enum!(ShutdownScriptImpl, ;
+ (0, Legacy),
+ (1, Bolt2),
+);
+
impl ShutdownScript {
/// Generates a P2WPKH script pubkey from the given [`PublicKey`].
- pub fn new_p2wpkh_from_pubkey(pubkey: PublicKey) -> Self {
+ pub(crate) fn new_p2wpkh_from_pubkey(pubkey: PublicKey) -> Self {
Self(ShutdownScriptImpl::Legacy(pubkey))
}
/// # Panics
///
/// This function may panic if given a segwit program with an invalid length.
- pub fn new_witness_program(version: u5, program: &[u8]) -> Self {
+ pub fn new_witness_program(version: NonZeroU8, program: &[u8]) -> Self {
+ let version = u5::try_from_u8(version.get()).expect("Invalid segwit version");
let script = Script::new_witness_program(version, program);
Self::try_from(script).expect("Invalid segwit program")
}
pub fn into_inner(self) -> Script {
self.into()
}
+
+ /// Returns the [`PublicKey`] used for a P2WPKH shutdown script if constructed directly from it.
+ pub fn as_legacy_pubkey(&self) -> Option<&PublicKey> {
+ match &self.0 {
+ ShutdownScriptImpl::Legacy(pubkey) => Some(pubkey),
+ ShutdownScriptImpl::Bolt2(_) => None,
+ }
+ }
+
+ /// Returns whether the shutdown script is compatible with the features as defined by BOLT #2.
+ ///
+ /// Specifically, checks for compliance with feature `option_shutdown_anysegwit`.
+ pub fn is_compatible(&self, features: &InitFeatures) -> bool {
+ match &self.0 {
+ ShutdownScriptImpl::Legacy(_) => true,
+ ShutdownScriptImpl::Bolt2(script) => is_bolt2_compliant(script, features),
+ }
+ }
+}
+
+fn is_bolt2_compliant(script: &Script, features: &InitFeatures) -> bool {
+ if script.is_p2pkh() || script.is_p2sh() || script.is_v0_p2wpkh() || script.is_v0_p2wsh() {
+ true
+ } else if features.supports_shutdown_anysegwit() {
+ script.is_witness_program() && script.as_bytes()[0] != SEGWIT_V0.into_u8()
+ } else {
+ false
+ }
}
impl TryFrom<Script> for ShutdownScript {
type Error = InvalidShutdownScript;
fn try_from((script, features): (Script, &InitFeatures)) -> Result<Self, Self::Error> {
- if script.is_p2pkh() || script.is_p2sh() || script.is_v0_p2wpkh() || script.is_v0_p2wsh() {
+ if is_bolt2_compliant(&script, features) {
Ok(Self(ShutdownScriptImpl::Bolt2(script)))
- } else if features.supports_shutdown_anysegwit() && script.is_witness_program() && script.as_bytes()[0] != SEGWIT_V0.into_u8() {
- Ok(Self(ShutdownScriptImpl::Bolt2(script))) // option_shutdown_anysegwit
} else {
Err(InvalidShutdownScript(script))
}
use bitcoin::blockdata::script::{Builder, Script};
use bitcoin::secp256k1::Secp256k1;
use bitcoin::secp256k1::key::{PublicKey, SecretKey};
+ use ln::features::InitFeatures;
use std::convert::TryFrom;
+ use core::num::NonZeroU8;
fn pubkey() -> bitcoin::util::ecdsa::PublicKey {
let secp_ctx = Secp256k1::signing_only();
let p2wpkh_script = Script::new_v0_wpkh(&pubkey_hash);
let shutdown_script = ShutdownScript::new_p2wpkh_from_pubkey(pubkey.key);
+ assert!(shutdown_script.is_compatible(&InitFeatures::known()));
+ assert!(shutdown_script.is_compatible(&InitFeatures::known().clear_shutdown_anysegwit()));
assert_eq!(shutdown_script.into_inner(), p2wpkh_script);
}
let p2pkh_script = Script::new_p2pkh(&pubkey_hash);
let shutdown_script = ShutdownScript::new_p2pkh(&pubkey_hash);
+ assert!(shutdown_script.is_compatible(&InitFeatures::known()));
+ assert!(shutdown_script.is_compatible(&InitFeatures::known().clear_shutdown_anysegwit()));
assert_eq!(shutdown_script.into_inner(), p2pkh_script);
assert!(ShutdownScript::try_from(p2pkh_script).is_ok());
}
let p2sh_script = Script::new_p2sh(&script_hash);
let shutdown_script = ShutdownScript::new_p2sh(&script_hash);
+ assert!(shutdown_script.is_compatible(&InitFeatures::known()));
+ assert!(shutdown_script.is_compatible(&InitFeatures::known().clear_shutdown_anysegwit()));
assert_eq!(shutdown_script.into_inner(), p2sh_script);
assert!(ShutdownScript::try_from(p2sh_script).is_ok());
}
let p2wpkh_script = Script::new_v0_wpkh(&pubkey_hash);
let shutdown_script = ShutdownScript::new_p2wpkh(&pubkey_hash);
+ assert!(shutdown_script.is_compatible(&InitFeatures::known()));
+ assert!(shutdown_script.is_compatible(&InitFeatures::known().clear_shutdown_anysegwit()));
assert_eq!(shutdown_script.into_inner(), p2wpkh_script);
assert!(ShutdownScript::try_from(p2wpkh_script).is_ok());
}
let p2wsh_script = Script::new_v0_wsh(&script_hash);
let shutdown_script = ShutdownScript::new_p2wsh(&script_hash);
+ assert!(shutdown_script.is_compatible(&InitFeatures::known()));
+ assert!(shutdown_script.is_compatible(&InitFeatures::known().clear_shutdown_anysegwit()));
assert_eq!(shutdown_script.into_inner(), p2wsh_script);
assert!(ShutdownScript::try_from(p2wsh_script).is_ok());
}
+ #[test]
+ fn generates_segwit_from_non_v0_witness_program() {
+ let version = u5::try_from_u8(16).unwrap();
+ let witness_program = Script::new_witness_program(version, &[0; 40]);
+
+ let version = NonZeroU8::new(version.to_u8()).unwrap();
+ let shutdown_script = ShutdownScript::new_witness_program(version, &[0; 40]);
+ assert!(shutdown_script.is_compatible(&InitFeatures::known()));
+ assert!(!shutdown_script.is_compatible(&InitFeatures::known().clear_shutdown_anysegwit()));
+ assert_eq!(shutdown_script.into_inner(), witness_program);
+ }
+
#[test]
fn fails_from_unsupported_script() {
let op_return = Script::new_op_return(&[0; 42]);
}
#[test]
- fn fails_from_invalid_segwit_v0_program() {
+ fn fails_from_invalid_segwit_v0_witness_program() {
let witness_program = Script::new_witness_program(u5::try_from_u8(0).unwrap(), &[0; 2]);
assert!(ShutdownScript::try_from(witness_program).is_err());
}
+
+ #[test]
+ fn fails_from_invalid_segwit_non_v0_witness_program() {
+ let witness_program = Script::new_witness_program(u5::try_from_u8(16).unwrap(), &[0; 42]);
+ assert!(ShutdownScript::try_from(witness_program).is_err());
+ }
}
projects / rust-lightning / blobdiff