Add message ordering return value to handling channel_reestablish
[rust-lightning] / src / ln / channelmanager.rs
index ed86b511bd64d0b772b820a194dcf5e0457647f4..e542a4d69dc61351b65da6ba30863dcdbfe6cd09 100644 (file)
@@ -26,7 +26,7 @@ use ln::channel::{Channel, ChannelError, ChannelKeys};
 use ln::channelmonitor::{ManyChannelMonitor, CLTV_CLAIM_BUFFER, HTLC_FAIL_TIMEOUT_BLOCKS};
 use ln::router::{Route,RouteHop};
 use ln::msgs;
-use ln::msgs::{HandleError,ChannelMessageHandler};
+use ln::msgs::{ChannelMessageHandler, HandleError, RAACommitmentOrder};
 use util::{byte_utils, events, internal_traits, rng};
 use util::sha2::Sha256;
 use util::ser::{Readable, Writeable};
@@ -105,6 +105,9 @@ mod channel_held_info {
                OutboundRoute {
                        route: Route,
                        session_priv: SecretKey,
+                       /// Technically we can recalculate this from the route, but we cache it here to avoid
+                       /// doing a double-pass on route when we get a failure back
+                       first_hop_htlc_msat: u64,
                },
        }
        #[cfg(test)]
@@ -113,6 +116,7 @@ mod channel_held_info {
                        HTLCSource::OutboundRoute {
                                route: Route { hops: Vec::new() },
                                session_priv: SecretKey::from_slice(&::secp256k1::Secp256k1::without_caps(), &[1; 32]).unwrap(),
+                               first_hop_htlc_msat: 0,
                        }
                }
        }
@@ -1112,6 +1116,7 @@ impl ChannelManager {
                                chan.send_htlc_and_commit(htlc_msat, payment_hash.clone(), htlc_cltv, HTLCSource::OutboundRoute {
                                        route: route.clone(),
                                        session_priv: session_priv.clone(),
+                                       first_hop_htlc_msat: htlc_msat,
                                }, onion_packet).map_err(|he| APIError::ChannelUnavailable{err: he.err})?
                        };
 
@@ -1376,11 +1381,21 @@ impl ChannelManager {
                match source {
                        HTLCSource::OutboundRoute { .. } => {
                                mem::drop(channel_state);
-
-                               let mut pending_events = self.pending_events.lock().unwrap();
-                               pending_events.push(events::Event::PaymentFailed {
-                                       payment_hash: payment_hash.clone()
-                               });
+                               if let &HTLCFailReason::ErrorPacket { ref err } = &onion_error {
+                                       let (channel_update, payment_retryable) = self.process_onion_failure(&source, err.data.clone());
+                                       let mut pending_events = self.pending_events.lock().unwrap();
+                                       if let Some(channel_update) = channel_update {
+                                               pending_events.push(events::Event::PaymentFailureNetworkUpdate {
+                                                       update: channel_update,
+                                               });
+                                       }
+                                       pending_events.push(events::Event::PaymentFailed {
+                                               payment_hash: payment_hash.clone(),
+                                               rejected_by_dest: !payment_retryable,
+                                       });
+                               } else {
+                                       panic!("should have onion error packet here");
+                               }
                        },
                        HTLCSource::PreviousHopData(HTLCPreviousHopData { short_channel_id, htlc_id, incoming_packet_shared_secret }) => {
                                let err_packet = match onion_error {
@@ -1794,9 +1809,206 @@ impl ChannelManager {
                Ok(())
        }
 
-       fn internal_update_fail_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFailHTLC) -> Result<Option<msgs::HTLCFailChannelUpdate>, MsgHandleErrInternal> {
+       // Process failure we got back from upstream on a payment we sent. Returns update and a boolean
+       // indicating that the payment itself failed
+       fn process_onion_failure(&self, htlc_source: &HTLCSource, mut packet_decrypted: Vec<u8>) -> (Option<msgs::HTLCFailChannelUpdate>, bool) {
+               if let &HTLCSource::OutboundRoute { ref route, ref session_priv, ref first_hop_htlc_msat } = htlc_source {
+                       macro_rules! onion_failure_log {
+                               ( $error_code_textual: expr, $error_code: expr, $reported_name: expr, $reported_value: expr ) => {
+                                       log_trace!(self, "{}({:#x}) {}({})", $error_code_textual, $error_code, $reported_name, $reported_value);
+                               };
+                               ( $error_code_textual: expr, $error_code: expr ) => {
+                                       log_trace!(self, "{}({})", $error_code_textual, $error_code);
+                               };
+                       }
+
+                       const BADONION: u16 = 0x8000;
+                       const PERM: u16 = 0x4000;
+                       const UPDATE: u16 = 0x1000;
+
+                       let mut res = None;
+                       let mut htlc_msat = *first_hop_htlc_msat;
+
+                       // Handle packed channel/node updates for passing back for the route handler
+                       Self::construct_onion_keys_callback(&self.secp_ctx, route, session_priv, |shared_secret, _, _, route_hop| {
+                               if res.is_some() { return; }
+
+                               let incoming_htlc_msat = htlc_msat;
+                               let amt_to_forward = htlc_msat - route_hop.fee_msat;
+                               htlc_msat = amt_to_forward;
+
+                               let ammag = ChannelManager::gen_ammag_from_shared_secret(&shared_secret);
+
+                               let mut decryption_tmp = Vec::with_capacity(packet_decrypted.len());
+                               decryption_tmp.resize(packet_decrypted.len(), 0);
+                               let mut chacha = ChaCha20::new(&ammag, &[0u8; 8]);
+                               chacha.process(&packet_decrypted, &mut decryption_tmp[..]);
+                               packet_decrypted = decryption_tmp;
+
+                               let is_from_final_node = route.hops.last().unwrap().pubkey == route_hop.pubkey;
+
+                               if let Ok(err_packet) = msgs::DecodedOnionErrorPacket::read(&mut Cursor::new(&packet_decrypted)) {
+                                       let um = ChannelManager::gen_um_from_shared_secret(&shared_secret);
+                                       let mut hmac = Hmac::new(Sha256::new(), &um);
+                                       hmac.input(&err_packet.encode()[32..]);
+                                       let mut calc_tag = [0u8; 32];
+                                       hmac.raw_result(&mut calc_tag);
+
+                                       if crypto::util::fixed_time_eq(&calc_tag, &err_packet.hmac) {
+                                               if err_packet.failuremsg.len() < 2 {
+                                                       // Useless packet that we can't use but it passed HMAC, so it
+                                                       // definitely came from the peer in question
+                                                       res = Some((None, !is_from_final_node));
+                                               } else {
+                                                       let error_code = byte_utils::slice_to_be16(&err_packet.failuremsg[0..2]);
+
+                                                       match error_code & 0xff {
+                                                               1|2|3 => {
+                                                                       // either from an intermediate or final node
+                                                                       //   invalid_realm(PERM|1),
+                                                                       //   temporary_node_failure(NODE|2)
+                                                                       //   permanent_node_failure(PERM|NODE|2)
+                                                                       //   required_node_feature_mssing(PERM|NODE|3)
+                                                                       res = Some((Some(msgs::HTLCFailChannelUpdate::NodeFailure {
+                                                                               node_id: route_hop.pubkey,
+                                                                               is_permanent: error_code & PERM == PERM,
+                                                                       }), !(error_code & PERM == PERM && is_from_final_node)));
+                                                                       // node returning invalid_realm is removed from network_map,
+                                                                       // although NODE flag is not set, TODO: or remove channel only?
+                                                                       // retry payment when removed node is not a final node
+                                                                       return;
+                                                               },
+                                                               _ => {}
+                                                       }
+
+                                                       if is_from_final_node {
+                                                               let payment_retryable = match error_code {
+                                                                       c if c == PERM|15 => false, // unknown_payment_hash
+                                                                       c if c == PERM|16 => false, // incorrect_payment_amount
+                                                                       17 => true, // final_expiry_too_soon
+                                                                       18 if err_packet.failuremsg.len() == 6 => { // final_incorrect_cltv_expiry
+                                                                               let _reported_cltv_expiry = byte_utils::slice_to_be32(&err_packet.failuremsg[2..2+4]);
+                                                                               true
+                                                                       },
+                                                                       19 if err_packet.failuremsg.len() == 10 => { // final_incorrect_htlc_amount
+                                                                               let _reported_incoming_htlc_msat = byte_utils::slice_to_be64(&err_packet.failuremsg[2..2+8]);
+                                                                               true
+                                                                       },
+                                                                       _ => {
+                                                                               // A final node has sent us either an invalid code or an error_code that
+                                                                               // MUST be sent from the processing node, or the formmat of failuremsg
+                                                                               // does not coform to the spec.
+                                                                               // Remove it from the network map and don't may retry payment
+                                                                               res = Some((Some(msgs::HTLCFailChannelUpdate::NodeFailure {
+                                                                                       node_id: route_hop.pubkey,
+                                                                                       is_permanent: true,
+                                                                               }), false));
+                                                                               return;
+                                                                       }
+                                                               };
+                                                               res = Some((None, payment_retryable));
+                                                               return;
+                                                       }
+
+                                                       // now, error_code should be only from the intermediate nodes
+                                                       match error_code {
+                                                               _c if error_code & PERM == PERM => {
+                                                                       res = Some((Some(msgs::HTLCFailChannelUpdate::ChannelClosed {
+                                                                               short_channel_id: route_hop.short_channel_id,
+                                                                               is_permanent: true,
+                                                                       }), false));
+                                                               },
+                                                               _c if error_code & UPDATE == UPDATE => {
+                                                                       let offset = match error_code {
+                                                                               c if c == UPDATE|7  => 0, // temporary_channel_failure
+                                                                               c if c == UPDATE|11 => 8, // amount_below_minimum
+                                                                               c if c == UPDATE|12 => 8, // fee_insufficient
+                                                                               c if c == UPDATE|13 => 4, // incorrect_cltv_expiry
+                                                                               c if c == UPDATE|14 => 0, // expiry_too_soon
+                                                                               c if c == UPDATE|20 => 2, // channel_disabled
+                                                                               _ =>  {
+                                                                                       // node sending unknown code
+                                                                                       res = Some((Some(msgs::HTLCFailChannelUpdate::NodeFailure {
+                                                                                               node_id: route_hop.pubkey,
+                                                                                               is_permanent: true,
+                                                                                       }), false));
+                                                                                       return;
+                                                                               }
+                                                                       };
+
+                                                                       if err_packet.failuremsg.len() >= offset + 2 {
+                                                                               let update_len = byte_utils::slice_to_be16(&err_packet.failuremsg[offset+2..offset+4]) as usize;
+                                                                               if err_packet.failuremsg.len() >= offset + 4 + update_len {
+                                                                                       if let Ok(chan_update) = msgs::ChannelUpdate::read(&mut Cursor::new(&err_packet.failuremsg[offset + 4..offset + 4 + update_len])) {
+                                                                                               // if channel_update should NOT have caused the failure:
+                                                                                               // MAY treat the channel_update as invalid.
+                                                                                               let is_chan_update_invalid = match error_code {
+                                                                                                       c if c == UPDATE|7 => { // temporary_channel_failure
+                                                                                                               false
+                                                                                                       },
+                                                                                                       c if c == UPDATE|11 => { // amount_below_minimum
+                                                                                                               let reported_htlc_msat = byte_utils::slice_to_be64(&err_packet.failuremsg[2..2+8]);
+                                                                                                               onion_failure_log!("amount_below_minimum", UPDATE|11, "htlc_msat", reported_htlc_msat);
+                                                                                                               incoming_htlc_msat > chan_update.contents.htlc_minimum_msat
+                                                                                                       },
+                                                                                                       c if c == UPDATE|12 => { // fee_insufficient
+                                                                                                               let reported_htlc_msat = byte_utils::slice_to_be64(&err_packet.failuremsg[2..2+8]);
+                                                                                                               let new_fee =  amt_to_forward.checked_mul(chan_update.contents.fee_proportional_millionths as u64).and_then(|prop_fee| { (prop_fee / 1000000).checked_add(chan_update.contents.fee_base_msat as u64) });
+                                                                                                               onion_failure_log!("fee_insufficient", UPDATE|12, "htlc_msat", reported_htlc_msat);
+                                                                                                               new_fee.is_none() || incoming_htlc_msat >= new_fee.unwrap() && incoming_htlc_msat >= amt_to_forward + new_fee.unwrap()
+                                                                                                       }
+                                                                                                       c if c == UPDATE|13 => { // incorrect_cltv_expiry
+                                                                                                               let reported_cltv_expiry = byte_utils::slice_to_be32(&err_packet.failuremsg[2..2+4]);
+                                                                                                               onion_failure_log!("incorrect_cltv_expiry", UPDATE|13, "cltv_expiry", reported_cltv_expiry);
+                                                                                                               route_hop.cltv_expiry_delta as u16 >= chan_update.contents.cltv_expiry_delta
+                                                                                                       },
+                                                                                                       c if c == UPDATE|20 => { // channel_disabled
+                                                                                                               let reported_flags = byte_utils::slice_to_be16(&err_packet.failuremsg[2..2+2]);
+                                                                                                               onion_failure_log!("channel_disabled", UPDATE|20, "flags", reported_flags);
+                                                                                                               chan_update.contents.flags & 0x01 == 0x01
+                                                                                                       },
+                                                                                                       c if c == UPDATE|21 => true, // expiry_too_far
+                                                                                                       _ => { unreachable!(); },
+                                                                                               };
+
+                                                                                               let msg = if is_chan_update_invalid { None } else {
+                                                                                                       Some(msgs::HTLCFailChannelUpdate::ChannelUpdateMessage {
+                                                                                                               msg: chan_update,
+                                                                                                       })
+                                                                                               };
+                                                                                               res = Some((msg, true));
+                                                                                               return;
+                                                                                       }
+                                                                               }
+                                                                       }
+                                                               },
+                                                               _c if error_code & BADONION == BADONION => {
+                                                                       //TODO
+                                                               },
+                                                               14 => { // expiry_too_soon
+                                                                       res = Some((None, true));
+                                                                       return;
+                                                               }
+                                                               _ => {
+                                                                       // node sending unknown code
+                                                                       res = Some((Some(msgs::HTLCFailChannelUpdate::NodeFailure {
+                                                                               node_id: route_hop.pubkey,
+                                                                               is_permanent: true,
+                                                                       }), false));
+                                                                       return;
+                                                               }
+                                                       }
+                                               }
+                                       }
+                               }
+                       }).expect("Route that we sent via spontaneously grew invalid keys in the middle of it?");
+                       res.unwrap_or((None, true))
+               } else { ((None, true)) }
+       }
+
+       fn internal_update_fail_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFailHTLC) -> Result<(), MsgHandleErrInternal> {
                let mut channel_state = self.channel_state.lock().unwrap();
-               let htlc_source = match channel_state.by_id.get_mut(&msg.channel_id) {
+               match channel_state.by_id.get_mut(&msg.channel_id) {
                        Some(chan) => {
                                if chan.get_their_node_id() != *their_node_id {
                                        //TODO: here and below MsgHandleErrInternal, #153 case
@@ -1807,65 +2019,7 @@ impl ChannelManager {
                        },
                        None => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
                }?;
-
-               match htlc_source {
-                       &HTLCSource::OutboundRoute { ref route, ref session_priv, .. } => {
-                               // Handle packed channel/node updates for passing back for the route handler
-                               let mut packet_decrypted = msg.reason.data.clone();
-                               let mut res = None;
-                               Self::construct_onion_keys_callback(&self.secp_ctx, &route, &session_priv, |shared_secret, _, _, route_hop| {
-                                       if res.is_some() { return; }
-
-                                       let ammag = ChannelManager::gen_ammag_from_shared_secret(&shared_secret);
-
-                                       let mut decryption_tmp = Vec::with_capacity(packet_decrypted.len());
-                                       decryption_tmp.resize(packet_decrypted.len(), 0);
-                                       let mut chacha = ChaCha20::new(&ammag, &[0u8; 8]);
-                                       chacha.process(&packet_decrypted, &mut decryption_tmp[..]);
-                                       packet_decrypted = decryption_tmp;
-
-                                       if let Ok(err_packet) = msgs::DecodedOnionErrorPacket::read(&mut Cursor::new(&packet_decrypted)) {
-                                               if err_packet.failuremsg.len() >= 2 {
-                                                       let um = ChannelManager::gen_um_from_shared_secret(&shared_secret);
-
-                                                       let mut hmac = Hmac::new(Sha256::new(), &um);
-                                                       hmac.input(&err_packet.encode()[32..]);
-                                                       let mut calc_tag = [0u8; 32];
-                                                       hmac.raw_result(&mut calc_tag);
-                                                       if crypto::util::fixed_time_eq(&calc_tag, &err_packet.hmac) {
-                                                               const UNKNOWN_CHAN: u16 = 0x4000|10;
-                                                               const TEMP_CHAN_FAILURE: u16 = 0x4000|7;
-                                                               match byte_utils::slice_to_be16(&err_packet.failuremsg[0..2]) {
-                                                                       TEMP_CHAN_FAILURE => {
-                                                                               if err_packet.failuremsg.len() >= 4 {
-                                                                                       let update_len = byte_utils::slice_to_be16(&err_packet.failuremsg[2..4]) as usize;
-                                                                                       if err_packet.failuremsg.len() >= 4 + update_len {
-                                                                                               if let Ok(chan_update) = msgs::ChannelUpdate::read(&mut Cursor::new(&err_packet.failuremsg[4..4 + update_len])) {
-                                                                                                       res = Some(msgs::HTLCFailChannelUpdate::ChannelUpdateMessage {
-                                                                                                               msg: chan_update,
-                                                                                                       });
-                                                                                               }
-                                                                                       }
-                                                                               }
-                                                                       },
-                                                                       UNKNOWN_CHAN => {
-                                                                               // No such next-hop. We know this came from the
-                                                                               // current node as the HMAC validated.
-                                                                               res = Some(msgs::HTLCFailChannelUpdate::ChannelClosed {
-                                                                                       short_channel_id: route_hop.short_channel_id,
-                                                                                       is_permanent: true,
-                                                                               });
-                                                                       },
-                                                                       _ => {}, //TODO: Enumerate all of these!
-                                                               }
-                                                       }
-                                               }
-                                       }
-                               }).unwrap();
-                               Ok(res)
-                       },
-                       _ => { Ok(None) },
-               }
+               Ok(())
        }
 
        fn internal_update_fail_malformed_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFailMalformedHTLC) -> Result<(), MsgHandleErrInternal> {
@@ -2014,7 +2168,7 @@ impl ChannelManager {
                Ok(())
        }
 
-       fn internal_channel_reestablish(&self, their_node_id: &PublicKey, msg: &msgs::ChannelReestablish) -> Result<(Option<msgs::FundingLocked>, Option<msgs::RevokeAndACK>, Option<msgs::CommitmentUpdate>), MsgHandleErrInternal> {
+       fn internal_channel_reestablish(&self, their_node_id: &PublicKey, msg: &msgs::ChannelReestablish) -> Result<(Option<msgs::FundingLocked>, Option<msgs::RevokeAndACK>, Option<msgs::CommitmentUpdate>, RAACommitmentOrder), MsgHandleErrInternal> {
                let (res, chan_monitor) = {
                        let mut channel_state = self.channel_state.lock().unwrap();
                        match channel_state.by_id.get_mut(&msg.channel_id) {
@@ -2022,9 +2176,9 @@ impl ChannelManager {
                                        if chan.get_their_node_id() != *their_node_id {
                                                return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
                                        }
-                                       let (funding_locked, revoke_and_ack, commitment_update, channel_monitor) = chan.channel_reestablish(msg)
+                                       let (funding_locked, revoke_and_ack, commitment_update, channel_monitor, order) = chan.channel_reestablish(msg)
                                                .map_err(|e| MsgHandleErrInternal::from_chan_maybe_close(e, msg.channel_id))?;
-                                       (Ok((funding_locked, revoke_and_ack, commitment_update)), channel_monitor)
+                                       (Ok((funding_locked, revoke_and_ack, commitment_update, order)), channel_monitor)
                                },
                                None => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))
                        }
@@ -2270,7 +2424,7 @@ impl ChannelMessageHandler for ChannelManager {
                handle_error!(self, self.internal_update_fulfill_htlc(their_node_id, msg), their_node_id)
        }
 
-       fn handle_update_fail_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFailHTLC) -> Result<Option<msgs::HTLCFailChannelUpdate>, HandleError> {
+       fn handle_update_fail_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFailHTLC) -> Result<(), HandleError> {
                handle_error!(self, self.internal_update_fail_htlc(their_node_id, msg), their_node_id)
        }
 
@@ -2294,7 +2448,7 @@ impl ChannelMessageHandler for ChannelManager {
                handle_error!(self, self.internal_announcement_signatures(their_node_id, msg), their_node_id)
        }
 
-       fn handle_channel_reestablish(&self, their_node_id: &PublicKey, msg: &msgs::ChannelReestablish) -> Result<(Option<msgs::FundingLocked>, Option<msgs::RevokeAndACK>, Option<msgs::CommitmentUpdate>), HandleError> {
+       fn handle_channel_reestablish(&self, their_node_id: &PublicKey, msg: &msgs::ChannelReestablish) -> Result<(Option<msgs::FundingLocked>, Option<msgs::RevokeAndACK>, Option<msgs::CommitmentUpdate>, RAACommitmentOrder), HandleError> {
                handle_error!(self, self.internal_channel_reestablish(their_node_id, msg), their_node_id)
        }
 
@@ -3142,8 +3296,9 @@ mod tests {
                        let events = origin_node.node.get_and_clear_pending_events();
                        assert_eq!(events.len(), 1);
                        match events[0] {
-                               Event::PaymentFailed { payment_hash } => {
+                               Event::PaymentFailed { payment_hash, rejected_by_dest } => {
                                        assert_eq!(payment_hash, our_payment_hash);
+                                       assert!(rejected_by_dest);
                                },
                                _ => panic!("Unexpected event"),
                        }
@@ -4783,6 +4938,7 @@ mod tests {
                                assert!(chan_msgs.0.is_none());
                        }
                        if pending_raa.0 {
+                               assert!(chan_msgs.3 == msgs::RAACommitmentOrder::RevokeAndACKFirst);
                                assert!(node_a.node.handle_revoke_and_ack(&node_b.node.get_our_node_id(), &chan_msgs.1.unwrap()).unwrap().is_none());
                                check_added_monitors!(node_a, 1);
                        } else {
@@ -4830,6 +4986,7 @@ mod tests {
                                assert!(chan_msgs.0.is_none());
                        }
                        if pending_raa.1 {
+                               assert!(chan_msgs.3 == msgs::RAACommitmentOrder::RevokeAndACKFirst);
                                assert!(node_b.node.handle_revoke_and_ack(&node_a.node.get_our_node_id(), &chan_msgs.1.unwrap()).unwrap().is_none());
                                check_added_monitors!(node_b, 1);
                        } else {
@@ -4910,8 +5067,9 @@ mod tests {
                                _ => panic!("Unexpected event"),
                        }
                        match events[1] {
-                               Event::PaymentFailed { payment_hash } => {
+                               Event::PaymentFailed { payment_hash, rejected_by_dest } => {
                                        assert_eq!(payment_hash, payment_hash_5);
+                                       assert!(rejected_by_dest);
                                },
                                _ => panic!("Unexpected event"),
                        }