X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning%2Fsrc%2Fln%2Fscript.rs;h=a9f44bae1aec79199230d467f426b50934c225dd;hb=6b8ad4ec33eb4f90395aac21c56c804b0b6c9429;hp=b6fcdbd19045c0586eb65f5686092319592c6888;hpb=ecc70757f9863a76ab9d4cc8b6bfe1a9cc9f4977;p=rust-lightning

diff --git a/lightning/src/ln/script.rs b/lightning/src/ln/script.rs
index b6fcdbd1..a9f44bae 100644
--- a/lightning/src/ln/script.rs
+++ b/lightning/src/ln/script.rs
@@ -3,21 +3,25 @@
 use bitcoin::blockdata::opcodes::all::OP_PUSHBYTES_0 as SEGWIT_V0;
 use bitcoin::blockdata::script::{Builder, Script};
 use bitcoin::hashes::Hash;
-use bitcoin::hash_types::{PubkeyHash, ScriptHash, WPubkeyHash, WScriptHash};
+use bitcoin::hash_types::{WPubkeyHash, WScriptHash};
 use bitcoin::secp256k1::key::PublicKey;
 
 use ln::features::InitFeatures;
+use ln::msgs::DecodeError;
+use util::ser::{Readable, Writeable, Writer};
 
 use core::convert::TryFrom;
 use core::num::NonZeroU8;
+use io;
 
 /// 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, PartialEq)]
 pub struct ShutdownScript(ShutdownScriptImpl);
 
 /// An error occurring when converting from [`Script`] to [`ShutdownScript`].
-#[derive(Debug)]
+#[derive(Clone, Debug)]
 pub struct InvalidShutdownScript {
 	/// The script that did not meet the requirements from [BOLT #2].
 	///
@@ -25,6 +29,7 @@ pub struct InvalidShutdownScript {
 	pub script: Script
 }
 
+#[derive(Clone, PartialEq)]
 enum ShutdownScriptImpl {
 	/// [`PublicKey`] used to form a P2WPKH script pubkey. Used to support backward-compatible
 	/// serialization.
@@ -34,20 +39,31 @@ enum ShutdownScriptImpl {
 	Bolt2(Script),
 }
 
-impl ShutdownScript {
-	/// Generates a P2WPKH script pubkey from the given [`PublicKey`].
-	pub fn new_p2wpkh_from_pubkey(pubkey: PublicKey) -> Self {
-		Self(ShutdownScriptImpl::Legacy(pubkey))
+impl Writeable for ShutdownScript {
+	fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
+		self.0.write(w)
 	}
 
-	/// Generates a P2PKH script pubkey from the given [`PubkeyHash`].
-	pub fn new_p2pkh(pubkey_hash: &PubkeyHash) -> Self {
-		Self(ShutdownScriptImpl::Bolt2(Script::new_p2pkh(pubkey_hash)))
+	fn serialized_length(&self) -> usize {
+		self.0.serialized_length()
 	}
+}
 
-	/// Generates a P2SH script pubkey from the given [`ScriptHash`].
-	pub fn new_p2sh(script_hash: &ScriptHash) -> Self {
-		Self(ShutdownScriptImpl::Bolt2(Script::new_p2sh(script_hash)))
+impl Readable for ShutdownScript {
+	fn read<R: io::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(crate) fn new_p2wpkh_from_pubkey(pubkey: PublicKey) -> Self {
+		Self(ShutdownScriptImpl::Legacy(pubkey))
 	}
 
 	/// Generates a P2WPKH script pubkey from the given [`WPubkeyHash`].
@@ -60,7 +76,10 @@ impl ShutdownScript {
 		Self(ShutdownScriptImpl::Bolt2(Script::new_v0_wsh(script_hash)))
 	}
 
-	/// Generates a P2WSH script pubkey from the given segwit version and program.
+	/// Generates a witness script pubkey from the given segwit version and program.
+	///
+	/// Note for version-zero witness scripts you must use [`ShutdownScript::new_p2wpkh`] or
+	/// [`ShutdownScript::new_p2wsh`] instead.
 	///
 	/// # Errors
 	///
@@ -97,7 +116,9 @@ impl ShutdownScript {
 	}
 }
 
-fn is_bolt2_compliant(script: &Script, features: &InitFeatures) -> bool {
+/// Check if a given script is compliant with BOLT 2's shutdown script requirements for the given
+/// counterparty features.
+pub(crate) 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() {
@@ -107,6 +128,8 @@ fn is_bolt2_compliant(script: &Script, features: &InitFeatures) -> bool {
 	}
 }
 
+// Note that this is only for our own shutdown scripts. Counterparties are still allowed to send us
+// non-witness shutdown scripts which this rejects.
 impl TryFrom<Script> for ShutdownScript {
 	type Error = InvalidShutdownScript;
 
@@ -115,11 +138,13 @@ impl TryFrom<Script> for ShutdownScript {
 	}
 }
 
+// Note that this is only for our own shutdown scripts. Counterparties are still allowed to send us
+// non-witness shutdown scripts which this rejects.
 impl TryFrom<(Script, &InitFeatures)> for ShutdownScript {
 	type Error = InvalidShutdownScript;
 
 	fn try_from((script, features): (Script, &InitFeatures)) -> Result<Self, Self::Error> {
-		if is_bolt2_compliant(&script, features) {
+		if is_bolt2_compliant(&script, features) && script.is_witness_program() {
 			Ok(Self(ShutdownScriptImpl::Bolt2(script)))
 		} else {
 			Err(InvalidShutdownScript { script })
@@ -137,6 +162,15 @@ impl Into<Script> for ShutdownScript {
 	}
 }
 
+impl core::fmt::Display for ShutdownScript{
+	fn fmt(&self, f: &mut core::fmt::Formatter) -> core::fmt::Result {
+		match &self.0 {
+			ShutdownScriptImpl::Legacy(_) => self.clone().into_inner().fmt(f),
+			ShutdownScriptImpl::Bolt2(script) => script.fmt(f),
+		}
+	}
+}
+
 #[cfg(test)]
 mod shutdown_script_tests {
 	use super::ShutdownScript;
@@ -178,30 +212,6 @@ mod shutdown_script_tests {
 		assert_eq!(shutdown_script.into_inner(), p2wpkh_script);
 	}
 
-	#[test]
-	fn generates_p2pkh_from_pubkey_hash() {
-		let pubkey_hash = pubkey().pubkey_hash();
-		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());
-	}
-
-	#[test]
-	fn generates_p2sh_from_script_hash() {
-		let script_hash = redeem_script().script_hash();
-		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());
-	}
-
 	#[test]
 	fn generates_p2wpkh_from_pubkey_hash() {
 		let pubkey_hash = pubkey().wpubkey_hash().unwrap();