Support option_data_loss_protect for remote peer

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

diff --git a/src/ln/channel.rs b/src/ln/channel.rs
index 5abbd4a29d0ea71cfa69b7b60363c936ccffea29..72b9fab1430beda48a2578a4bf0e211abec11e60 100644 (file)
--- a/src/ln/channel.rs
+++ b/src/ln/channel.rs
@@ -16,7 +16,7 @@ use secp256k1::{Secp256k1,Signature};
 use secp256k1;
 
 use ln::msgs;
-use ln::msgs::{DecodeError, OptionalField, LocalFeatures};
+use ln::msgs::{DecodeError, OptionalField, LocalFeatures, DataLossProtect};
 use ln::channelmonitor::ChannelMonitor;
 use ln::channelmanager::{PendingHTLCStatus, HTLCSource, HTLCFailReason, HTLCFailureMsg, PendingForwardHTLCInfo, RAACommitmentOrder, PaymentPreimage, PaymentHash, BREAKDOWN_TIMEOUT, MAX_LOCAL_BREAKDOWN_TIMEOUT};
 use ln::chan_utils::{TxCreationKeys,HTLCOutputInCommitment,HTLC_SUCCESS_TX_WEIGHT,HTLC_TIMEOUT_TX_WEIGHT};
@@ -3256,6 +3256,20 @@ impl Channel {
        pub fn get_channel_reestablish(&self) -> msgs::ChannelReestablish {
                assert_eq!(self.channel_state & ChannelState::PeerDisconnected as u32, ChannelState::PeerDisconnected as u32);
                assert_ne!(self.cur_remote_commitment_transaction_number, INITIAL_COMMITMENT_NUMBER);
+               let data_loss_protect = if self.cur_remote_commitment_transaction_number + 1 < INITIAL_COMMITMENT_NUMBER {
+                       let remote_last_secret = self.channel_monitor.get_secret(self.cur_remote_commitment_transaction_number + 2).unwrap();
+                       log_trace!(self, "Enough info to generate a Data Loss Protect with per_commitment_secret {}", log_bytes!(remote_last_secret));
+                       OptionalField::Present(DataLossProtect {
+                               your_last_per_commitment_secret: remote_last_secret,
+                               my_current_per_commitment_point: PublicKey::from_secret_key(&self.secp_ctx, &self.build_local_commitment_secret(self.cur_local_commitment_transaction_number + 1))
+                       })
+               } else {
+                       log_debug!(self, "We don't seen yet any revoked secret, if this channnel has already been updated it means we are fallen-behind, you should wait for other peer closing");
+                       OptionalField::Present(DataLossProtect {
+                               your_last_per_commitment_secret: [0;32],
+                               my_current_per_commitment_point: PublicKey::from_secret_key(&self.secp_ctx, &self.build_local_commitment_secret(self.cur_local_commitment_transaction_number))
+                       })
+               };
                msgs::ChannelReestablish {
                        channel_id: self.channel_id(),
                        // The protocol has two different commitment number concepts - the "commitment
@@ -3276,7 +3290,7 @@ impl Channel {
                        // dropped this channel on disconnect as it hasn't yet reached FundingSent so we can't
                        // overflow here.
                        next_remote_commitment_number: INITIAL_COMMITMENT_NUMBER - self.cur_remote_commitment_transaction_number - 1,
-                       data_loss_protect: OptionalField::Absent,
+                       data_loss_protect,
                }
        }