Properly handle ChannelError::Close results in update_fee.
[rust-lightning] / src / ln / channelmonitor.rs
index 7f584aeba804e3b86ee3a12c18ee9aabb12ae61a..6ce4b22d5a8c63109765be350c53883ad9d91855 100644 (file)
@@ -26,7 +26,7 @@ use secp256k1::{Secp256k1,Message,Signature};
 use secp256k1::key::{SecretKey,PublicKey};
 use secp256k1;
 
-use ln::msgs::{DecodeError, HandleError};
+use ln::msgs::DecodeError;
 use ln::chan_utils;
 use ln::chan_utils::HTLCOutputInCommitment;
 use chain::chaininterface::{ChainListener, ChainWatchInterface, BroadcasterInterface};
@@ -74,6 +74,14 @@ pub enum ChannelMonitorUpdateErr {
        PermanentFailure,
 }
 
+/// General Err type for ChannelMonitor actions. Generally, this implies that the data provided is
+/// inconsistent with the ChannelMonitor being called. eg for ChannelMonitor::insert_combine this
+/// means you tried to merge two monitors for different channels or for a channel which was
+/// restored from a backup and then generated new commitment updates.
+/// Contains a human-readable error message.
+#[derive(Debug)]
+pub struct MonitorUpdateError(pub &'static str);
+
 /// Simple trait indicating ability to track a set of ChannelMonitors and multiplex events between
 /// them. Generally should be implemented by keeping a local SimpleManyChannelMonitor and passing
 /// events to it, while also taking any add_update_monitor events and passing them to some remote
@@ -158,7 +166,7 @@ impl<Key : Send + cmp::Eq + hash::Hash + 'static> SimpleManyChannelMonitor<Key>
        }
 
        /// Adds or udpates the monitor which monitors the channel referred to by the given key.
-       pub fn add_update_monitor_by_key(&self, key: Key, monitor: ChannelMonitor) -> Result<(), HandleError> {
+       pub fn add_update_monitor_by_key(&self, key: Key, monitor: ChannelMonitor) -> Result<(), MonitorUpdateError> {
                let mut monitors = self.monitors.lock().unwrap();
                match monitors.get_mut(&key) {
                        Some(orig_monitor) => {
@@ -408,12 +416,12 @@ impl ChannelMonitor {
        /// Inserts a revocation secret into this channel monitor. Prunes old preimages if neither
        /// needed by local commitment transactions HTCLs nor by remote ones. Unless we haven't already seen remote
        /// commitment transaction's secret, they are de facto pruned (we can use revocation key).
-       pub(super) fn provide_secret(&mut self, idx: u64, secret: [u8; 32]) -> Result<(), HandleError> {
+       pub(super) fn provide_secret(&mut self, idx: u64, secret: [u8; 32]) -> Result<(), MonitorUpdateError> {
                let pos = ChannelMonitor::place_secret(idx);
                for i in 0..pos {
                        let (old_secret, old_idx) = self.old_secrets[i as usize];
                        if ChannelMonitor::derive_secret(secret, pos, old_idx) != old_secret {
-                               return Err(HandleError{err: "Previous secret did not match new one", action: None})
+                               return Err(MonitorUpdateError("Previous secret did not match new one"));
                        }
                }
                self.old_secrets[pos as usize] = (secret, idx);
@@ -453,37 +461,11 @@ impl ChannelMonitor {
                Ok(())
        }
 
-       /// Tracks the next revocation point which may be required to claim HTLC outputs which we know
-       /// the preimage of in case the remote end force-closes using their latest state. When called at
-       /// channel opening revocation point is the CURRENT one used for first commitment tx. Needed in case of sizeable push_msat.
-       pub(super) fn provide_their_next_revocation_point(&mut self, their_next_revocation_point: Option<(u64, PublicKey)>) {
-               if let Some(new_revocation_point) = their_next_revocation_point {
-                       match self.their_cur_revocation_points {
-                               Some(old_points) => {
-                                       if old_points.0 == new_revocation_point.0 + 1 {
-                                               self.their_cur_revocation_points = Some((old_points.0, old_points.1, Some(new_revocation_point.1)));
-                                       } else if old_points.0 == new_revocation_point.0 + 2 {
-                                               if let Some(old_second_point) = old_points.2 {
-                                                       self.their_cur_revocation_points = Some((old_points.0 - 1, old_second_point, Some(new_revocation_point.1)));
-                                               } else {
-                                                       self.their_cur_revocation_points = Some((new_revocation_point.0, new_revocation_point.1, None));
-                                               }
-                                       } else {
-                                               self.their_cur_revocation_points = Some((new_revocation_point.0, new_revocation_point.1, None));
-                                       }
-                               },
-                               None => {
-                                       self.their_cur_revocation_points = Some((new_revocation_point.0, new_revocation_point.1, None));
-                               }
-                       }
-               }
-       }
-
        /// Informs this monitor of the latest remote (ie non-broadcastable) commitment transaction.
        /// The monitor watches for it to be broadcasted and then uses the HTLC information (and
        /// possibly future revocation/preimage information) to claim outputs where possible.
        /// We cache also the mapping hash:commitment number to lighten pruning of old preimages by watchtowers.
-       pub(super) fn provide_latest_remote_commitment_tx_info(&mut self, unsigned_commitment_tx: &Transaction, htlc_outputs: Vec<HTLCOutputInCommitment>, commitment_number: u64) {
+       pub(super) fn provide_latest_remote_commitment_tx_info(&mut self, unsigned_commitment_tx: &Transaction, htlc_outputs: Vec<HTLCOutputInCommitment>, commitment_number: u64, their_revocation_point: PublicKey) {
                // TODO: Encrypt the htlc_outputs data with the single-hash of the commitment transaction
                // so that a remote monitor doesn't learn anything unless there is a malicious close.
                // (only maybe, sadly we cant do the same for local info, as we need to be aware of
@@ -493,6 +475,25 @@ impl ChannelMonitor {
                }
                self.remote_claimable_outpoints.insert(unsigned_commitment_tx.txid(), htlc_outputs);
                self.current_remote_commitment_number = commitment_number;
+               //TODO: Merge this into the other per-remote-transaction output storage stuff
+               match self.their_cur_revocation_points {
+                       Some(old_points) => {
+                               if old_points.0 == commitment_number + 1 {
+                                       self.their_cur_revocation_points = Some((old_points.0, old_points.1, Some(their_revocation_point)));
+                               } else if old_points.0 == commitment_number + 2 {
+                                       if let Some(old_second_point) = old_points.2 {
+                                               self.their_cur_revocation_points = Some((old_points.0 - 1, old_second_point, Some(their_revocation_point)));
+                                       } else {
+                                               self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
+                                       }
+                               } else {
+                                       self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
+                               }
+                       },
+                       None => {
+                               self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
+                       }
+               }
        }
 
        /// Informs this monitor of the latest local (ie broadcastable) commitment transaction. The
@@ -537,12 +538,12 @@ impl ChannelMonitor {
        /// Combines this ChannelMonitor with the information contained in the other ChannelMonitor.
        /// After a successful call this ChannelMonitor is up-to-date and is safe to use to monitor the
        /// chain for new blocks/transactions.
-       pub fn insert_combine(&mut self, mut other: ChannelMonitor) -> Result<(), HandleError> {
+       pub fn insert_combine(&mut self, mut other: ChannelMonitor) -> Result<(), MonitorUpdateError> {
                if self.funding_txo.is_some() {
                        // We should be able to compare the entire funding_txo, but in fuzztarget its trivially
                        // easy to collide the funding_txo hash and have a different scriptPubKey.
                        if other.funding_txo.is_some() && other.funding_txo.as_ref().unwrap().0 != self.funding_txo.as_ref().unwrap().0 {
-                               return Err(HandleError{err: "Funding transaction outputs are not identical!", action: None});
+                               return Err(MonitorUpdateError("Funding transaction outputs are not identical!"));
                        }
                } else {
                        self.funding_txo = other.funding_txo.take();
@@ -830,14 +831,14 @@ impl ChannelMonitor {
        //we want to leave out (eg funding_txo, etc).
 
        /// Can only fail if idx is < get_min_seen_secret
-       pub(super) fn get_secret(&self, idx: u64) -> Result<[u8; 32], HandleError> {
+       pub(super) fn get_secret(&self, idx: u64) -> Option<[u8; 32]> {
                for i in 0..self.old_secrets.len() {
                        if (idx & (!((1 << i) - 1))) == self.old_secrets[i].1 {
-                               return Ok(ChannelMonitor::derive_secret(self.old_secrets[i].0, i as u8, idx))
+                               return Some(ChannelMonitor::derive_secret(self.old_secrets[i].0, i as u8, idx))
                        }
                }
                assert!(idx < self.get_min_seen_secret());
-               Err(HandleError{err: "idx too low", action: None})
+               None
        }
 
        pub(super) fn get_min_seen_secret(&self) -> u64 {
@@ -888,16 +889,18 @@ impl ChannelMonitor {
                if commitment_number >= self.get_min_seen_secret() {
                        let secret = self.get_secret(commitment_number).unwrap();
                        let per_commitment_key = ignore_error!(SecretKey::from_slice(&self.secp_ctx, &secret));
-                       let (revocation_pubkey, b_htlc_key) = match self.key_storage {
-                               KeyStorage::PrivMode { ref revocation_base_key, ref htlc_base_key, .. } => {
+                       let (revocation_pubkey, b_htlc_key, local_payment_key) = match self.key_storage {
+                               KeyStorage::PrivMode { ref revocation_base_key, ref htlc_base_key, ref payment_base_key, .. } => {
                                        let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
                                        (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &PublicKey::from_secret_key(&self.secp_ctx, &revocation_base_key))),
-                                       ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &per_commitment_point, &PublicKey::from_secret_key(&self.secp_ctx, &htlc_base_key))))
+                                       ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &per_commitment_point, &PublicKey::from_secret_key(&self.secp_ctx, &htlc_base_key))),
+                                       Some(ignore_error!(chan_utils::derive_private_key(&self.secp_ctx, &per_commitment_point, &payment_base_key))))
                                },
                                KeyStorage::SigsMode { ref revocation_base_key, ref htlc_base_key, .. } => {
                                        let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
                                        (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &revocation_base_key)),
-                                       ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &per_commitment_point, &htlc_base_key)))
+                                       ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &per_commitment_point, &htlc_base_key)),
+                                       None)
                                },
                        };
                        let delayed_key = ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key), &self.their_delayed_payment_base_key.unwrap()));
@@ -909,6 +912,13 @@ impl ChannelMonitor {
                        let revokeable_redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.our_to_self_delay, &delayed_key);
                        let revokeable_p2wsh = revokeable_redeemscript.to_v0_p2wsh();
 
+                       let local_payment_p2wpkh = if let Some(payment_key) = local_payment_key {
+                               // Note that the Network here is ignored as we immediately drop the address for the
+                               // script_pubkey version.
+                               let payment_hash160 = Hash160::from_data(&PublicKey::from_secret_key(&self.secp_ctx, &payment_key).serialize());
+                               Some(Builder::new().push_opcode(opcodes::All::OP_PUSHBYTES_0).push_slice(&payment_hash160[..]).into_script())
+                       } else { None };
+
                        let mut total_value = 0;
                        let mut values = Vec::new();
                        let mut inputs = Vec::new();
@@ -928,23 +938,12 @@ impl ChannelMonitor {
                                        htlc_idxs.push(None);
                                        values.push(outp.value);
                                        total_value += outp.value;
-                               } else if outp.script_pubkey.is_v0_p2wpkh() {
-                                       match self.key_storage {
-                                               KeyStorage::PrivMode { ref payment_base_key, .. } => {
-                                                       let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
-                                                       if let Ok(local_key) = chan_utils::derive_private_key(&self.secp_ctx, &per_commitment_point, &payment_base_key) {
-                                                               spendable_outputs.push(SpendableOutputDescriptor::DynamicOutputP2WPKH {
-                                                                       outpoint: BitcoinOutPoint { txid: commitment_txid, vout: idx as u32 },
-                                                                       key: local_key,
-                                                                       output: outp.clone(),
-                                                               });
-                                                       }
-                                               }
-                                               KeyStorage::SigsMode { .. } => {
-                                                       //TODO: we need to ensure an offline client will generate the event when it
-                                                       // cames back online after only the watchtower saw the transaction
-                                               }
-                                       }
+                               } else if Some(&outp.script_pubkey) == local_payment_p2wpkh.as_ref() {
+                                       spendable_outputs.push(SpendableOutputDescriptor::DynamicOutputP2WPKH {
+                                               outpoint: BitcoinOutPoint { txid: commitment_txid, vout: idx as u32 },
+                                               key: local_payment_key.unwrap(),
+                                               output: outp.clone(),
+                                       });
                                }
                        }
 
@@ -1082,7 +1081,6 @@ impl ChannelMonitor {
                                                Some(their_htlc_base_key) => ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, revocation_point, &their_htlc_base_key)),
                                        };
 
-
                                        for (idx, outp) in tx.output.iter().enumerate() {
                                                if outp.script_pubkey.is_v0_p2wpkh() {
                                                        match self.key_storage {
@@ -1094,11 +1092,8 @@ impl ChannelMonitor {
                                                                                        output: outp.clone(),
                                                                                });
                                                                        }
-                                                               }
-                                                               KeyStorage::SigsMode { .. } => {
-                                                                       //TODO: we need to ensure an offline client will generate the event when it
-                                                                       // cames back online after only the watchtower saw the transaction
-                                                               }
+                                                               },
+                                                               KeyStorage::SigsMode { .. } => {}
                                                        }
                                                        break; // Only to_remote ouput is claimable
                                                }
@@ -1215,7 +1210,7 @@ impl ChannelMonitor {
                        };
                }
 
-               let secret = ignore_error!(self.get_secret(commitment_number));
+               let secret = if let Some(secret) = self.get_secret(commitment_number) { secret } else { return (None, None); };
                let per_commitment_key = ignore_error!(SecretKey::from_slice(&self.secp_ctx, &secret));
                let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
                let revocation_pubkey = match self.key_storage {
@@ -1808,7 +1803,7 @@ mod tests {
                                        idx -= 1;
                                }
                                assert_eq!(monitor.get_min_seen_secret(), idx + 1);
-                               assert!(monitor.get_secret(idx).is_err());
+                               assert!(monitor.get_secret(idx).is_none());
                        };
                }
 
@@ -1870,7 +1865,7 @@ mod tests {
 
                        secrets.push([0; 32]);
                        secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
-                       assert_eq!(monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap_err().err,
+                       assert_eq!(monitor.provide_secret(281474976710654, secrets.last().unwrap().clone()).unwrap_err().0,
                                        "Previous secret did not match new one");
                }
 
@@ -1896,7 +1891,7 @@ mod tests {
 
                        secrets.push([0; 32]);
                        secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
-                       assert_eq!(monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap_err().err,
+                       assert_eq!(monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap_err().0,
                                        "Previous secret did not match new one");
                }
 
@@ -1922,7 +1917,7 @@ mod tests {
 
                        secrets.push([0; 32]);
                        secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
-                       assert_eq!(monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap_err().err,
+                       assert_eq!(monitor.provide_secret(281474976710652, secrets.last().unwrap().clone()).unwrap_err().0,
                                        "Previous secret did not match new one");
                }
 
@@ -1968,7 +1963,7 @@ mod tests {
 
                        secrets.push([0; 32]);
                        secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
-                       assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap_err().err,
+                       assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap_err().0,
                                        "Previous secret did not match new one");
                }
 
@@ -2004,7 +1999,7 @@ mod tests {
 
                        secrets.push([0; 32]);
                        secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2").unwrap());
-                       assert_eq!(monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap_err().err,
+                       assert_eq!(monitor.provide_secret(281474976710650, secrets.last().unwrap().clone()).unwrap_err().0,
                                        "Previous secret did not match new one");
                }
 
@@ -2050,7 +2045,7 @@ mod tests {
 
                        secrets.push([0; 32]);
                        secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
-                       assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap_err().err,
+                       assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap_err().0,
                                        "Previous secret did not match new one");
                }
 
@@ -2096,7 +2091,7 @@ mod tests {
 
                        secrets.push([0; 32]);
                        secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17").unwrap());
-                       assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap_err().err,
+                       assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap_err().0,
                                        "Previous secret did not match new one");
                }
 
@@ -2142,7 +2137,7 @@ mod tests {
 
                        secrets.push([0; 32]);
                        secrets.last_mut().unwrap()[0..32].clone_from_slice(&hex::decode("a7efbc61aac46d34f77778bac22c8a20c6a46ca460addc49009bda875ec88fa4").unwrap());
-                       assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap_err().err,
+                       assert_eq!(monitor.provide_secret(281474976710648, secrets.last().unwrap().clone()).unwrap_err().0,
                                        "Previous secret did not match new one");
                }
        }
@@ -2153,10 +2148,10 @@ mod tests {
                let logger = Arc::new(TestLogger::new());
                let dummy_sig = Signature::from_der(&secp_ctx, &hex::decode("3045022100fa86fa9a36a8cd6a7bb8f06a541787d51371d067951a9461d5404de6b928782e02201c8b7c334c10aed8976a3a465be9a28abff4cb23acbf00022295b378ce1fa3cd").unwrap()[..]).unwrap();
 
+               let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap());
                macro_rules! dummy_keys {
                        () => {
                                {
-                                       let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap());
                                        TxCreationKeys {
                                                per_commitment_point: dummy_key.clone(),
                                                revocation_key: dummy_key.clone(),
@@ -2225,10 +2220,10 @@ mod tests {
                monitor.set_their_to_self_delay(10);
 
                monitor.provide_latest_local_commitment_tx_info(dummy_tx.clone(), dummy_keys!(), 0, preimages_to_local_htlcs!(preimages[0..10]));
-               monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[5..15]), 281474976710655);
-               monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[15..20]), 281474976710654);
-               monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[17..20]), 281474976710653);
-               monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[18..20]), 281474976710652);
+               monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[5..15]), 281474976710655, dummy_key);
+               monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[15..20]), 281474976710654, dummy_key);
+               monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[17..20]), 281474976710653, dummy_key);
+               monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[18..20]), 281474976710652, dummy_key);
                for &(ref preimage, ref hash) in preimages.iter() {
                        monitor.provide_payment_preimage(hash, preimage);
                }