X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning%2Fsrc%2Fln%2Fchannel.rs;h=81372ee3da862cb35908da437e2a2fe578ef75f2;hb=607cd6f523179d49452b7c9a525a75f350b2a63a;hp=cd6448d088cdec223c3927dafbfcde2eff270e06;hpb=b04d1b868fe28bea2e4c711e6e6d2470d2b98d77;p=rust-lightning

diff --git a/lightning/src/ln/channel.rs b/lightning/src/ln/channel.rs
index cd6448d0..81372ee3 100644
--- a/lightning/src/ln/channel.rs
+++ b/lightning/src/ln/channel.rs
@@ -34,7 +34,7 @@ use crate::chain::BestBlock;
 use crate::chain::chaininterface::{FeeEstimator, ConfirmationTarget, LowerBoundedFeeEstimator};
 use crate::chain::channelmonitor::{ChannelMonitor, ChannelMonitorUpdate, ChannelMonitorUpdateStep, LATENCY_GRACE_PERIOD_BLOCKS};
 use crate::chain::transaction::{OutPoint, TransactionData};
-use crate::chain::keysinterface::{Sign, KeysInterface};
+use crate::chain::keysinterface::{Sign, KeysInterface, BaseSign};
 use crate::util::events::ClosureReason;
 use crate::util::ser::{Readable, ReadableArgs, Writeable, Writer, VecWriter};
 use crate::util::logger::Logger;
@@ -737,6 +737,10 @@ pub(super) struct Channel<Signer: Sign> {
 
 	// We track whether we already emitted a `ChannelReady` event.
 	channel_ready_event_emitted: bool,
+
+	/// The unique identifier used to re-derive the private key material for the channel through
+	/// [`KeysInterface::derive_channel_signer`].
+	channel_keys_id: [u8; 32],
 }
 
 #[cfg(any(test, fuzzing))]
@@ -1072,6 +1076,7 @@ impl<Signer: Sign> Channel<Signer> {
 			historical_inbound_htlc_fulfills: HashSet::new(),
 
 			channel_type: Self::get_initial_channel_type(&config),
+			channel_keys_id,
 		})
 	}
 
@@ -1419,6 +1424,7 @@ impl<Signer: Sign> Channel<Signer> {
 			historical_inbound_htlc_fulfills: HashSet::new(),
 
 			channel_type,
+			channel_keys_id,
 		};
 
 		Ok(chan)
@@ -2192,7 +2198,13 @@ impl<Signer: Sign> Channel<Signer> {
 		&self.get_counterparty_pubkeys().funding_pubkey
 	}
 
-	pub fn funding_created<L: Deref>(&mut self, msg: &msgs::FundingCreated, best_block: BestBlock, logger: &L) -> Result<(msgs::FundingSigned, ChannelMonitor<Signer>, Option<msgs::ChannelReady>), ChannelError> where L::Target: Logger {
+	pub fn funding_created<K: Deref, L: Deref>(
+		&mut self, msg: &msgs::FundingCreated, best_block: BestBlock, keys_source: &K, logger: &L
+	) -> Result<(msgs::FundingSigned, ChannelMonitor<<K::Target as KeysInterface>::Signer>, Option<msgs::ChannelReady>), ChannelError>
+	where
+		K::Target: KeysInterface,
+		L::Target: Logger
+	{
 		if self.is_outbound() {
 			return Err(ChannelError::Close("Received funding_created for an outbound channel?".to_owned()));
 		}
@@ -2215,7 +2227,7 @@ impl<Signer: Sign> Channel<Signer> {
 		self.channel_transaction_parameters.funding_outpoint = Some(funding_txo);
 		// This is an externally observable change before we finish all our checks.  In particular
 		// funding_created_signature may fail.
-		self.holder_signer.ready_channel(&self.channel_transaction_parameters);
+		self.holder_signer.provide_channel_parameters(&self.channel_transaction_parameters);
 
 		let (counterparty_initial_commitment_txid, initial_commitment_tx, signature) = match self.funding_created_signature(&msg.signature, logger) {
 			Ok(res) => res,
@@ -2247,7 +2259,9 @@ impl<Signer: Sign> Channel<Signer> {
 		let funding_txo_script = funding_redeemscript.to_v0_p2wsh();
 		let obscure_factor = get_commitment_transaction_number_obscure_factor(&self.get_holder_pubkeys().payment_point, &self.get_counterparty_pubkeys().payment_point, self.is_outbound());
 		let shutdown_script = self.shutdown_scriptpubkey.clone().map(|script| script.into_inner());
-		let channel_monitor = ChannelMonitor::new(self.secp_ctx.clone(), self.holder_signer.clone(),
+		let mut monitor_signer = keys_source.derive_channel_signer(self.channel_value_satoshis, self.channel_keys_id);
+		monitor_signer.provide_channel_parameters(&self.channel_transaction_parameters);
+		let channel_monitor = ChannelMonitor::new(self.secp_ctx.clone(), monitor_signer,
 		                                          shutdown_script, self.get_holder_selected_contest_delay(),
 		                                          &self.destination_script, (funding_txo, funding_txo_script.clone()),
 		                                          &self.channel_transaction_parameters,
@@ -2272,7 +2286,13 @@ impl<Signer: Sign> Channel<Signer> {
 
 	/// Handles a funding_signed message from the remote end.
 	/// If this call is successful, broadcast the funding transaction (and not before!)
-	pub fn funding_signed<L: Deref>(&mut self, msg: &msgs::FundingSigned, best_block: BestBlock, logger: &L) -> Result<(ChannelMonitor<Signer>, Transaction, Option<msgs::ChannelReady>), ChannelError> where L::Target: Logger {
+	pub fn funding_signed<K: Deref, L: Deref>(
+		&mut self, msg: &msgs::FundingSigned, best_block: BestBlock, keys_source: &K, logger: &L
+	) -> Result<(ChannelMonitor<<K::Target as KeysInterface>::Signer>, Transaction, Option<msgs::ChannelReady>), ChannelError>
+	where
+		K::Target: KeysInterface,
+		L::Target: Logger
+	{
 		if !self.is_outbound() {
 			return Err(ChannelError::Close("Received funding_signed for an inbound channel?".to_owned()));
 		}
@@ -2324,7 +2344,9 @@ impl<Signer: Sign> Channel<Signer> {
 		let funding_txo_script = funding_redeemscript.to_v0_p2wsh();
 		let obscure_factor = get_commitment_transaction_number_obscure_factor(&self.get_holder_pubkeys().payment_point, &self.get_counterparty_pubkeys().payment_point, self.is_outbound());
 		let shutdown_script = self.shutdown_scriptpubkey.clone().map(|script| script.into_inner());
-		let channel_monitor = ChannelMonitor::new(self.secp_ctx.clone(), self.holder_signer.clone(),
+		let mut monitor_signer = keys_source.derive_channel_signer(self.channel_value_satoshis, self.channel_keys_id);
+		monitor_signer.provide_channel_parameters(&self.channel_transaction_parameters);
+		let channel_monitor = ChannelMonitor::new(self.secp_ctx.clone(), monitor_signer,
 		                                          shutdown_script, self.get_holder_selected_contest_delay(),
 		                                          &self.destination_script, (funding_txo, funding_txo_script),
 		                                          &self.channel_transaction_parameters,
@@ -5250,7 +5272,7 @@ impl<Signer: Sign> Channel<Signer> {
 		}
 
 		self.channel_transaction_parameters.funding_outpoint = Some(funding_txo);
-		self.holder_signer.ready_channel(&self.channel_transaction_parameters);
+		self.holder_signer.provide_channel_parameters(&self.channel_transaction_parameters);
 
 		let signature = match self.get_outbound_funding_created_signature(logger) {
 			Ok(res) => res,
@@ -5936,7 +5958,7 @@ impl<Signer: Sign> Channel<Signer> {
 	}
 }
 
-const SERIALIZATION_VERSION: u8 = 2;
+const SERIALIZATION_VERSION: u8 = 3;
 const MIN_SERIALIZATION_VERSION: u8 = 2;
 
 impl_writeable_tlv_based_enum!(InboundHTLCRemovalReason,;
@@ -5998,7 +6020,7 @@ impl<Signer: Sign> Writeable for Channel<Signer> {
 		// Note that we write out as if remove_uncommitted_htlcs_and_mark_paused had just been
 		// called.
 
-		write_ver_prefix!(writer, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
+		write_ver_prefix!(writer, MIN_SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
 
 		// `user_id` used to be a single u64 value. In order to remain backwards compatible with
 		// versions prior to 0.0.113, the u128 is serialized as two separate u64 values. We write
@@ -6280,6 +6302,7 @@ impl<Signer: Sign> Writeable for Channel<Signer> {
 			(21, self.outbound_scid_alias, required),
 			(23, channel_ready_event_emitted, option),
 			(25, user_id_high_opt, option),
+			(27, self.channel_keys_id, required),
 		});
 
 		Ok(())
@@ -6316,16 +6339,20 @@ impl<'a, K: Deref> ReadableArgs<(&'a K, u32)> for Channel<<K::Target as KeysInte
 
 		let latest_monitor_update_id = Readable::read(reader)?;
 
-		let keys_len: u32 = Readable::read(reader)?;
-		let mut keys_data = Vec::with_capacity(cmp::min(keys_len as usize, MAX_ALLOC_SIZE));
-		while keys_data.len() != keys_len as usize {
-			// Read 1KB at a time to avoid accidentally allocating 4GB on corrupted channel keys
-			let mut data = [0; 1024];
-			let read_slice = &mut data[0..cmp::min(1024, keys_len as usize - keys_data.len())];
-			reader.read_exact(read_slice)?;
-			keys_data.extend_from_slice(read_slice);
+		let mut keys_data = None;
+		if ver <= 2 {
+			// Read the serialize signer bytes. We'll choose to deserialize them or not based on whether
+			// the `channel_keys_id` TLV is present below.
+			let keys_len: u32 = Readable::read(reader)?;
+			keys_data = Some(Vec::with_capacity(cmp::min(keys_len as usize, MAX_ALLOC_SIZE)));
+			while keys_data.as_ref().unwrap().len() != keys_len as usize {
+				// Read 1KB at a time to avoid accidentally allocating 4GB on corrupted channel keys
+				let mut data = [0; 1024];
+				let read_slice = &mut data[0..cmp::min(1024, keys_len as usize - keys_data.as_ref().unwrap().len())];
+				reader.read_exact(read_slice)?;
+				keys_data.as_mut().unwrap().extend_from_slice(read_slice);
+			}
 		}
-		let holder_signer = keys_source.read_chan_signer(&keys_data)?;
 
 		// Read the old serialization for shutdown_pubkey, preferring the TLV field later if set.
 		let mut shutdown_scriptpubkey = match <PublicKey as Readable>::read(reader) {
@@ -6543,6 +6570,7 @@ impl<'a, K: Deref> ReadableArgs<(&'a K, u32)> for Channel<<K::Target as KeysInte
 		let mut channel_ready_event_emitted = None;
 
 		let mut user_id_high_opt: Option<u64> = None;
+		let mut channel_keys_id: Option<[u8; 32]> = None;
 
 		read_tlv_fields!(reader, {
 			(0, announcement_sigs, option),
@@ -6562,8 +6590,25 @@ impl<'a, K: Deref> ReadableArgs<(&'a K, u32)> for Channel<<K::Target as KeysInte
 			(21, outbound_scid_alias, option),
 			(23, channel_ready_event_emitted, option),
 			(25, user_id_high_opt, option),
+			(27, channel_keys_id, option),
 		});
 
+		let (channel_keys_id, holder_signer) = if let Some(channel_keys_id) = channel_keys_id {
+			let mut holder_signer = keys_source.derive_channel_signer(channel_value_satoshis, channel_keys_id);
+			// If we've gotten to the funding stage of the channel, populate the signer with its
+			// required channel parameters.
+			let non_shutdown_state = channel_state & (!MULTI_STATE_FLAGS);
+			if non_shutdown_state >= (ChannelState::FundingCreated as u32) {
+				holder_signer.provide_channel_parameters(&channel_parameters);
+			}
+			(channel_keys_id, holder_signer)
+		} else {
+			// `keys_data` can be `None` if we had corrupted data.
+			let keys_data = keys_data.ok_or(DecodeError::InvalidValue)?;
+			let holder_signer = keys_source.read_chan_signer(&keys_data)?;
+			(holder_signer.channel_keys_id(), holder_signer)
+		};
+
 		if let Some(preimages) = preimages_opt {
 			let mut iter = preimages.into_iter();
 			for htlc in pending_outbound_htlcs.iter_mut() {
@@ -6713,6 +6758,7 @@ impl<'a, K: Deref> ReadableArgs<(&'a K, u32)> for Channel<<K::Target as KeysInte
 			historical_inbound_htlc_fulfills,
 
 			channel_type: channel_type.unwrap(),
+			channel_keys_id,
 		})
 	}
 }
@@ -7023,10 +7069,10 @@ mod tests {
 		}]};
 		let funding_outpoint = OutPoint{ txid: tx.txid(), index: 0 };
 		let funding_created_msg = node_a_chan.get_outbound_funding_created(tx.clone(), funding_outpoint, &&logger).unwrap();
-		let (funding_signed_msg, _, _) = node_b_chan.funding_created(&funding_created_msg, best_block, &&logger).unwrap();
+		let (funding_signed_msg, _, _) = node_b_chan.funding_created(&funding_created_msg, best_block, &&keys_provider, &&logger).unwrap();
 
 		// Node B --> Node A: funding signed
-		let _ = node_a_chan.funding_signed(&funding_signed_msg, best_block, &&logger);
+		let _ = node_a_chan.funding_signed(&funding_signed_msg, best_block, &&keys_provider, &&logger);
 
 		// Now disconnect the two nodes and check that the commitment point in
 		// Node B's channel_reestablish message is sane.
@@ -7296,7 +7342,7 @@ mod tests {
 				selected_contest_delay: 144
 			});
 		chan.channel_transaction_parameters.funding_outpoint = Some(funding_info);
-		signer.ready_channel(&chan.channel_transaction_parameters);
+		signer.provide_channel_parameters(&chan.channel_transaction_parameters);
 
 		assert_eq!(counterparty_pubkeys.payment_point.serialize()[..],
 		           hex::decode("032c0b7cf95324a07d05398b240174dc0c2be444d96b159aa6c7f7b1e668680991").unwrap()[..]);