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)]
HTLCSource::OutboundRoute {
route: Route { hops: Vec::new() },
session_priv: SecretKey::from_slice(&::secp256k1::Secp256k1::without_caps(), &[1; 32]).unwrap(),
+ first_hop_htlc_msat: 0,
}
}
}
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})?
};
Ok(())
}
+ // 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<Option<msgs::HTLCFailChannelUpdate>, MsgHandleErrInternal> {
let mut channel_state = self.channel_state.lock().unwrap();
let htlc_source = match channel_state.by_id.get_mut(&msg.channel_id) {
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) },
+ // we are the origin node and update route information
+ // also determine if the payment is retryable
+ if let &HTLCSource::OutboundRoute { .. } = htlc_source {
+ let (channel_update, _payment_retry) = self.process_onion_failure(htlc_source, msg.reason.data.clone());
+ Ok(channel_update)
+ // TODO: include pyament_retry info in PaymentFailed event that will be
+ // fired when receiving revoke_and_ack
+ } else {
+ Ok(None)
}
}
projects / rust-lightning / commitdiff