Support option_upfront_shutdown_script for local peer

[rust-lightning] / src / ln / channel.rs

diff --git a/src/ln/channel.rs b/src/ln/channel.rs
index cee70e5c39993911341a8b0b8c514d1dfac97274..bf5d357645ff21a90e9ed9c0565ac0ed239053d3 100644 (file)
--- a/src/ln/channel.rs
+++ b/src/ln/channel.rs
@@ -522,7 +522,7 @@ impl Channel {
 
        /// Creates a new channel from a remote sides' request for one.
        /// Assumes chain_hash has already been checked and corresponds with what we expect!
-       pub fn new_from_req(fee_estimator: &FeeEstimator, keys_provider: &Arc<KeysInterface>, their_node_id: PublicKey, _their_local_features: LocalFeatures, msg: &msgs::OpenChannel, user_id: u64, logger: Arc<Logger>, config: &UserConfig) -> Result<Channel, ChannelError> {
+       pub fn new_from_req(fee_estimator: &FeeEstimator, keys_provider: &Arc<KeysInterface>, their_node_id: PublicKey, their_local_features: LocalFeatures, msg: &msgs::OpenChannel, user_id: u64, logger: Arc<Logger>, config: &UserConfig) -> Result<Channel, ChannelError> {
                let chan_keys = keys_provider.get_channel_keys(true);
                let mut local_config = (*config).channel_options.clone();
 
@@ -625,6 +625,27 @@ impl Channel {
                channel_monitor.set_their_base_keys(&msg.htlc_basepoint, &msg.delayed_payment_basepoint);
                channel_monitor.set_their_to_self_delay(msg.to_self_delay);
 
+               let their_shutdown_scriptpubkey = if their_local_features.supports_upfront_shutdown_script() {
+                       match &msg.shutdown_scriptpubkey {
+                               &OptionalField::Present(ref script) => {
+                                       // Peer is signaling upfront_shutdown and has provided a non-accepted scriptpubkey format. We enforce it while receiving shutdown msg
+                                       if script.is_p2pkh() || script.is_p2sh() || script.is_v0_p2wsh() || script.is_v0_p2wpkh() {
+                                               Some(script.clone())
+                                       // Peer is signaling upfront_shutdown and has opt-out with a 0-length script. We don't enforce anything
+                                       } else if script.len() == 0 {
+                                               None
+                                       // Peer is signaling upfront_shutdown and has provided a non-accepted scriptpubkey format. Fail the channel
+                                       } else {
+                                               return Err(ChannelError::Close("Peer is signaling upfront_shutdown but has provided a non-accepted scriptpubkey format"));
+                                       }
+                               },
+                               // Peer is signaling upfront shutdown but don't opt-out with correct mechanism (a.k.a 0-length script). Peer looks buggy, we fail the channel
+                               &OptionalField::Absent => {
+                                       return Err(ChannelError::Close("Peer is signaling upfront_shutdown but we don't get any script. Use 0-length script to opt-out"));
+                               }
+                       }
+               } else { None };
+
                let mut chan = Channel {
                        user_id: user_id,
                        config: local_config,
@@ -692,7 +713,7 @@ impl Channel {
                        their_prev_commitment_point: None,
                        their_node_id: their_node_id,
 
-                       their_shutdown_scriptpubkey: None,
+                       their_shutdown_scriptpubkey,
 
                        channel_monitor: channel_monitor,
 
@@ -1341,7 +1362,7 @@ impl Channel {
 
        // Message handlers:
 
-       pub fn accept_channel(&mut self, msg: &msgs::AcceptChannel, config: &UserConfig, _their_local_features: LocalFeatures) -> Result<(), ChannelError> {
+       pub fn accept_channel(&mut self, msg: &msgs::AcceptChannel, config: &UserConfig, their_local_features: LocalFeatures) -> Result<(), ChannelError> {
                // Check sanity of message fields:
                if !self.channel_outbound {
                        return Err(ChannelError::Close("Got an accept_channel message from an inbound peer"));
@@ -1400,6 +1421,27 @@ impl Channel {
                        return Err(ChannelError::Close("We consider the minimum depth to be unreasonably large"));
                }
 
+               let their_shutdown_scriptpubkey = if their_local_features.supports_upfront_shutdown_script() {
+                       match &msg.shutdown_scriptpubkey {
+                               &OptionalField::Present(ref script) => {
+                                       // Peer is signaling upfront_shutdown and has provided a non-accepted scriptpubkey format. We enforce it while receiving shutdown msg
+                                       if script.is_p2pkh() || script.is_p2sh() || script.is_v0_p2wsh() || script.is_v0_p2wpkh() {
+                                               Some(script.clone())
+                                       // Peer is signaling upfront_shutdown and has opt-out with a 0-length script. We don't enforce anything
+                                       } else if script.len() == 0 {
+                                               None
+                                       // Peer is signaling upfront_shutdown and has provided a non-accepted scriptpubkey format. Fail the channel
+                                       } else {
+                                               return Err(ChannelError::Close("Peer is signaling upfront_shutdown but has provided a non-accepted scriptpubkey format"));
+                                       }
+                               },
+                               // Peer is signaling upfront shutdown but don't opt-out with correct mechanism (a.k.a 0-length script). Peer looks buggy, we fail the channel
+                               &OptionalField::Absent => {
+                                       return Err(ChannelError::Close("Peer is signaling upfront_shutdown but we don't get any script. Use 0-length script to opt-out"));
+                               }
+                       }
+               } else { None };
+
                self.channel_monitor.set_their_base_keys(&msg.htlc_basepoint, &msg.delayed_payment_basepoint);
 
                self.their_dust_limit_satoshis = msg.dust_limit_satoshis;
@@ -1415,6 +1457,7 @@ impl Channel {
                self.their_delayed_payment_basepoint = Some(msg.delayed_payment_basepoint);
                self.their_htlc_basepoint = Some(msg.htlc_basepoint);
                self.their_cur_commitment_point = Some(msg.first_per_commitment_point);
+               self.their_shutdown_scriptpubkey = their_shutdown_scriptpubkey;
 
                let obscure_factor = self.get_commitment_transaction_number_obscure_factor();
                self.channel_monitor.set_commitment_obscure_factor(obscure_factor);