/// Returns update, a boolean indicating that the payment itself failed, the short channel id of
/// the responsible channel, and the error code.
#[inline]
-pub(super) fn process_onion_failure<T: secp256k1::Signing, L: Deref>(secp_ctx: &Secp256k1<T>, logger: &L, htlc_source: &HTLCSource, mut packet_decrypted: Vec<u8>) -> (Option<NetworkUpdate>, Option<u64>, bool, Option<u16>, Option<Vec<u8>>) where L::Target: Logger {
- if let &HTLCSource::OutboundRoute { ref path, ref session_priv, ref first_hop_htlc_msat, .. } = htlc_source {
- let mut res = None;
- let mut htlc_msat = *first_hop_htlc_msat;
- let mut error_code_ret = None;
- let mut error_packet_ret = None;
- let mut is_from_final_node = false;
-
- // Handle packed channel/node updates for passing back for the route handler
- construct_onion_keys_callback(secp_ctx, &path.hops, session_priv, |shared_secret, _, _, route_hop, route_hop_idx| {
- if res.is_some() { return; }
-
- let amt_to_forward = htlc_msat - route_hop.fee_msat;
- htlc_msat = amt_to_forward;
-
- let ammag = gen_ammag_from_shared_secret(shared_secret.as_ref());
-
- 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;
-
- // The failing hop includes either the inbound channel to the recipient or the outbound
- // channel from the current hop (i.e., the next hop's inbound channel).
- is_from_final_node = route_hop_idx + 1 == path.hops.len();
- let failing_route_hop = if is_from_final_node { route_hop } else { &path.hops[route_hop_idx + 1] };
-
- if let Ok(err_packet) = msgs::DecodedOnionErrorPacket::read(&mut Cursor::new(&packet_decrypted)) {
- let um = gen_um_from_shared_secret(shared_secret.as_ref());
- let mut hmac = HmacEngine::<Sha256>::new(&um);
- hmac.input(&err_packet.encode()[32..]);
-
- if fixed_time_eq(&Hmac::from_engine(hmac).into_inner(), &err_packet.hmac) {
- if let Some(error_code_slice) = err_packet.failuremsg.get(0..2) {
- const BADONION: u16 = 0x8000;
- const PERM: u16 = 0x4000;
- const NODE: u16 = 0x2000;
- const UPDATE: u16 = 0x1000;
-
- let error_code = u16::from_be_bytes(error_code_slice.try_into().expect("len is 2"));
- error_code_ret = Some(error_code);
- error_packet_ret = Some(err_packet.failuremsg[2..].to_vec());
-
- let (debug_field, debug_field_size) = errors::get_onion_debug_field(error_code);
-
- // indicate that payment parameter has failed and no need to
- // update Route object
- let payment_failed = match error_code & 0xff {
- 15|16|17|18|19|23 => true,
- _ => false,
- } && is_from_final_node; // PERM bit observed below even if this error is from the intermediate nodes
-
- let mut network_update = None;
- let mut short_channel_id = None;
-
- if error_code & BADONION == BADONION {
- // If the error code has the BADONION bit set, always blame the channel
- // from the node "originating" the error to its next hop. The
- // "originator" is ultimately actually claiming that its counterparty
- // is the one who is failing the HTLC.
- // If the "originator" here isn't lying we should really mark the
- // next-hop node as failed entirely, but we can't be confident in that,
- // as it would allow any node to get us to completely ban one of its
- // counterparties. Instead, we simply remove the channel in question.
+pub(super) fn process_onion_failure<T: secp256k1::Signing, L: Deref>(
+ secp_ctx: &Secp256k1<T>, logger: &L, htlc_source: &HTLCSource, mut packet_decrypted: Vec<u8>
+) -> (Option<NetworkUpdate>, Option<u64>, bool, Option<u16>, Option<Vec<u8>>)
+where L::Target: Logger {
+ let (path, session_priv, first_hop_htlc_msat) = if let &HTLCSource::OutboundRoute {
+ ref path, ref session_priv, ref first_hop_htlc_msat, ..
+ } = htlc_source {
+ (path, session_priv, first_hop_htlc_msat)
+ } else { unreachable!() };
+ let mut res = None;
+ let mut htlc_msat = *first_hop_htlc_msat;
+ let mut error_code_ret = None;
+ let mut error_packet_ret = None;
+ let mut is_from_final_node = false;
+
+ // Handle packed channel/node updates for passing back for the route handler
+ construct_onion_keys_callback(secp_ctx, &path.hops, session_priv, |shared_secret, _, _, route_hop, route_hop_idx| {
+ if res.is_some() { return; }
+
+ let amt_to_forward = htlc_msat - route_hop.fee_msat;
+ htlc_msat = amt_to_forward;
+
+ let ammag = gen_ammag_from_shared_secret(shared_secret.as_ref());
+
+ 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;
+
+ // The failing hop includes either the inbound channel to the recipient or the outbound
+ // channel from the current hop (i.e., the next hop's inbound channel).
+ is_from_final_node = route_hop_idx + 1 == path.hops.len();
+ let failing_route_hop = if is_from_final_node { route_hop } else { &path.hops[route_hop_idx + 1] };
+
+ let err_packet = match msgs::DecodedOnionErrorPacket::read(&mut Cursor::new(&packet_decrypted)) {
+ Ok(p) => p,
+ Err(_) => return
+ };
+ let um = gen_um_from_shared_secret(shared_secret.as_ref());
+ let mut hmac = HmacEngine::<Sha256>::new(&um);
+ hmac.input(&err_packet.encode()[32..]);
+
+ if !fixed_time_eq(&Hmac::from_engine(hmac).into_inner(), &err_packet.hmac) { return }
+ let error_code_slice = match err_packet.failuremsg.get(0..2) {
+ Some(s) => s,
+ None => {
+ // Useless packet that we can't use but it passed HMAC, so it
+ // definitely came from the peer in question
+ let network_update = Some(NetworkUpdate::NodeFailure {
+ node_id: route_hop.pubkey,
+ is_permanent: true,
+ });
+ let short_channel_id = Some(route_hop.short_channel_id);
+ res = Some((network_update, short_channel_id, !is_from_final_node));
+ return
+ }
+ };
+ const BADONION: u16 = 0x8000;
+ const PERM: u16 = 0x4000;
+ const NODE: u16 = 0x2000;
+ const UPDATE: u16 = 0x1000;
+
+ let error_code = u16::from_be_bytes(error_code_slice.try_into().expect("len is 2"));
+ error_code_ret = Some(error_code);
+ error_packet_ret = Some(err_packet.failuremsg[2..].to_vec());
+
+ let (debug_field, debug_field_size) = errors::get_onion_debug_field(error_code);
+
+ // indicate that payment parameter has failed and no need to
+ // update Route object
+ let payment_failed = match error_code & 0xff {
+ 15|16|17|18|19|23 => true,
+ _ => false,
+ } && is_from_final_node; // PERM bit observed below even if this error is from the intermediate nodes
+
+ let mut network_update = None;
+ let mut short_channel_id = None;
+
+ if error_code & BADONION == BADONION {
+ // If the error code has the BADONION bit set, always blame the channel
+ // from the node "originating" the error to its next hop. The
+ // "originator" is ultimately actually claiming that its counterparty
+ // is the one who is failing the HTLC.
+ // If the "originator" here isn't lying we should really mark the
+ // next-hop node as failed entirely, but we can't be confident in that,
+ // as it would allow any node to get us to completely ban one of its
+ // counterparties. Instead, we simply remove the channel in question.
+ network_update = Some(NetworkUpdate::ChannelFailure {
+ short_channel_id: failing_route_hop.short_channel_id,
+ is_permanent: true,
+ });
+ } else if error_code & NODE == NODE {
+ let is_permanent = error_code & PERM == PERM;
+ network_update = Some(NetworkUpdate::NodeFailure { node_id: route_hop.pubkey, is_permanent });
+ short_channel_id = Some(route_hop.short_channel_id);
+ } else if error_code & PERM == PERM {
+ if !payment_failed {
+ network_update = Some(NetworkUpdate::ChannelFailure {
+ short_channel_id: failing_route_hop.short_channel_id,
+ is_permanent: true,
+ });
+ short_channel_id = Some(failing_route_hop.short_channel_id);
+ }
+ } else if error_code & UPDATE == UPDATE {
+ if let Some(update_len_slice) = err_packet.failuremsg.get(debug_field_size+2..debug_field_size+4) {
+ let update_len = u16::from_be_bytes(update_len_slice.try_into().expect("len is 2")) as usize;
+ if let Some(mut update_slice) = err_packet.failuremsg.get(debug_field_size + 4..debug_field_size + 4 + update_len) {
+ // Historically, the BOLTs were unclear if the message type
+ // bytes should be included here or not. The BOLTs have now
+ // been updated to indicate that they *are* included, but many
+ // nodes still send messages without the type bytes, so we
+ // support both here.
+ // TODO: Switch to hard require the type prefix, as the current
+ // permissiveness introduces the (although small) possibility
+ // that we fail to decode legitimate channel updates that
+ // happen to start with ChannelUpdate::TYPE, i.e., [0x01, 0x02].
+ if update_slice.len() > 2 && update_slice[0..2] == msgs::ChannelUpdate::TYPE.to_be_bytes() {
+ update_slice = &update_slice[2..];
+ } else {
+ log_trace!(logger, "Failure provided features a channel update without type prefix. Deprecated, but allowing for now.");
+ }
+ let update_opt = msgs::ChannelUpdate::read(&mut Cursor::new(&update_slice));
+ if update_opt.is_ok() || update_slice.is_empty() {
+ // if channel_update should NOT have caused the failure:
+ // MAY treat the channel_update as invalid.
+ let is_chan_update_invalid = match error_code & 0xff {
+ 7 => false,
+ 11 => update_opt.is_ok() &&
+ amt_to_forward >
+ update_opt.as_ref().unwrap().contents.htlc_minimum_msat,
+ 12 => update_opt.is_ok() && amt_to_forward
+ .checked_mul(update_opt.as_ref().unwrap()
+ .contents.fee_proportional_millionths as u64)
+ .map(|prop_fee| prop_fee / 1_000_000)
+ .and_then(|prop_fee| prop_fee.checked_add(
+ update_opt.as_ref().unwrap().contents.fee_base_msat as u64))
+ .map(|fee_msats| route_hop.fee_msat >= fee_msats)
+ .unwrap_or(false),
+ 13 => update_opt.is_ok() &&
+ route_hop.cltv_expiry_delta as u16 >=
+ update_opt.as_ref().unwrap().contents.cltv_expiry_delta,
+ 14 => false, // expiry_too_soon; always valid?
+ 20 => update_opt.as_ref().unwrap().contents.flags & 2 == 0,
+ _ => false, // unknown error code; take channel_update as valid
+ };
+ if is_chan_update_invalid {
+ // This probably indicates the node which forwarded
+ // to the node in question corrupted something.
network_update = Some(NetworkUpdate::ChannelFailure {
- short_channel_id: failing_route_hop.short_channel_id,
+ short_channel_id: route_hop.short_channel_id,
is_permanent: true,
});
- } else if error_code & NODE == NODE {
- let is_permanent = error_code & PERM == PERM;
- network_update = Some(NetworkUpdate::NodeFailure { node_id: route_hop.pubkey, is_permanent });
- short_channel_id = Some(route_hop.short_channel_id);
- } else if error_code & PERM == PERM {
- if !payment_failed {
- network_update = Some(NetworkUpdate::ChannelFailure {
- short_channel_id: failing_route_hop.short_channel_id,
- is_permanent: true,
- });
- short_channel_id = Some(failing_route_hop.short_channel_id);
- }
- } else if error_code & UPDATE == UPDATE {
- if let Some(update_len_slice) = err_packet.failuremsg.get(debug_field_size+2..debug_field_size+4) {
- let update_len = u16::from_be_bytes(update_len_slice.try_into().expect("len is 2")) as usize;
- if let Some(mut update_slice) = err_packet.failuremsg.get(debug_field_size + 4..debug_field_size + 4 + update_len) {
- // Historically, the BOLTs were unclear if the message type
- // bytes should be included here or not. The BOLTs have now
- // been updated to indicate that they *are* included, but many
- // nodes still send messages without the type bytes, so we
- // support both here.
- // TODO: Switch to hard require the type prefix, as the current
- // permissiveness introduces the (although small) possibility
- // that we fail to decode legitimate channel updates that
- // happen to start with ChannelUpdate::TYPE, i.e., [0x01, 0x02].
- if update_slice.len() > 2 && update_slice[0..2] == msgs::ChannelUpdate::TYPE.to_be_bytes() {
- update_slice = &update_slice[2..];
- } else {
- log_trace!(logger, "Failure provided features a channel update without type prefix. Deprecated, but allowing for now.");
- }
- let update_opt = msgs::ChannelUpdate::read(&mut Cursor::new(&update_slice));
- if update_opt.is_ok() || update_slice.is_empty() {
- // if channel_update should NOT have caused the failure:
- // MAY treat the channel_update as invalid.
- let is_chan_update_invalid = match error_code & 0xff {
- 7 => false,
- 11 => update_opt.is_ok() &&
- amt_to_forward >
- update_opt.as_ref().unwrap().contents.htlc_minimum_msat,
- 12 => update_opt.is_ok() && amt_to_forward
- .checked_mul(update_opt.as_ref().unwrap()
- .contents.fee_proportional_millionths as u64)
- .map(|prop_fee| prop_fee / 1_000_000)
- .and_then(|prop_fee| prop_fee.checked_add(
- update_opt.as_ref().unwrap().contents.fee_base_msat as u64))
- .map(|fee_msats| route_hop.fee_msat >= fee_msats)
- .unwrap_or(false),
- 13 => update_opt.is_ok() &&
- route_hop.cltv_expiry_delta as u16 >=
- update_opt.as_ref().unwrap().contents.cltv_expiry_delta,
- 14 => false, // expiry_too_soon; always valid?
- 20 => update_opt.as_ref().unwrap().contents.flags & 2 == 0,
- _ => false, // unknown error code; take channel_update as valid
- };
- if is_chan_update_invalid {
- // This probably indicates the node which forwarded
- // to the node in question corrupted something.
- network_update = Some(NetworkUpdate::ChannelFailure {
- short_channel_id: route_hop.short_channel_id,
- is_permanent: true,
- });
- } else {
- if let Ok(chan_update) = update_opt {
- // Make sure the ChannelUpdate contains the expected
- // short channel id.
- if failing_route_hop.short_channel_id == chan_update.contents.short_channel_id {
- short_channel_id = Some(failing_route_hop.short_channel_id);
- } else {
- log_info!(logger, "Node provided a channel_update for which it was not authoritative, ignoring.");
- }
- network_update = Some(NetworkUpdate::ChannelUpdateMessage {
- msg: chan_update,
- })
- } else {
- network_update = Some(NetworkUpdate::ChannelFailure {
- short_channel_id: route_hop.short_channel_id,
- is_permanent: false,
- });
- }
- };
- } else {
- // If the channel_update had a non-zero length (i.e. was
- // present) but we couldn't read it, treat it as a total
- // node failure.
- log_info!(logger,
- "Failed to read a channel_update of len {} in an onion",
- update_slice.len());
- }
+ } else {
+ if let Ok(chan_update) = update_opt {
+ // Make sure the ChannelUpdate contains the expected
+ // short channel id.
+ if failing_route_hop.short_channel_id == chan_update.contents.short_channel_id {
+ short_channel_id = Some(failing_route_hop.short_channel_id);
+ } else {
+ log_info!(logger, "Node provided a channel_update for which it was not authoritative, ignoring.");
}
- }
- if network_update.is_none() {
- // They provided an UPDATE which was obviously bogus, not worth
- // trying to relay through them anymore.
- network_update = Some(NetworkUpdate::NodeFailure {
- node_id: route_hop.pubkey,
- is_permanent: true,
+ network_update = Some(NetworkUpdate::ChannelUpdateMessage {
+ msg: chan_update,
+ })
+ } else {
+ network_update = Some(NetworkUpdate::ChannelFailure {
+ short_channel_id: route_hop.short_channel_id,
+ is_permanent: false,
});
}
- if short_channel_id.is_none() {
- short_channel_id = Some(route_hop.short_channel_id);
- }
- } else if payment_failed {
- // Only blame the hop when a value in the HTLC doesn't match the
- // corresponding value in the onion.
- short_channel_id = match error_code & 0xff {
- 18|19 => Some(route_hop.short_channel_id),
- _ => None,
- };
- } else {
- // We can't understand their error messages and they failed to
- // forward...they probably can't understand our forwards so its
- // really not worth trying any further.
- network_update = Some(NetworkUpdate::NodeFailure {
- node_id: route_hop.pubkey,
- is_permanent: true,
- });
- short_channel_id = Some(route_hop.short_channel_id);
- }
-
- res = Some((network_update, short_channel_id, !(error_code & PERM == PERM && is_from_final_node)));
-
- let (description, title) = errors::get_onion_error_description(error_code);
- if debug_field_size > 0 && err_packet.failuremsg.len() >= 4 + debug_field_size {
- log_info!(logger, "Onion Error[from {}: {}({:#x}) {}({})] {}", route_hop.pubkey, title, error_code, debug_field, log_bytes!(&err_packet.failuremsg[4..4+debug_field_size]), description);
- }
- else {
- log_info!(logger, "Onion Error[from {}: {}({:#x})] {}", route_hop.pubkey, title, error_code, description);
- }
+ };
} else {
- // Useless packet that we can't use but it passed HMAC, so it
- // definitely came from the peer in question
- let network_update = Some(NetworkUpdate::NodeFailure {
- node_id: route_hop.pubkey,
- is_permanent: true,
- });
- let short_channel_id = Some(route_hop.short_channel_id);
- res = Some((network_update, short_channel_id, !is_from_final_node));
+ // If the channel_update had a non-zero length (i.e. was
+ // present) but we couldn't read it, treat it as a total
+ // node failure.
+ log_info!(logger,
+ "Failed to read a channel_update of len {} in an onion",
+ update_slice.len());
}
}
}
- }).expect("Route that we sent via spontaneously grew invalid keys in the middle of it?");
- if let Some((channel_update, short_channel_id, payment_retryable)) = res {
- (channel_update, short_channel_id, payment_retryable, error_code_ret, error_packet_ret)
+ if network_update.is_none() {
+ // They provided an UPDATE which was obviously bogus, not worth
+ // trying to relay through them anymore.
+ network_update = Some(NetworkUpdate::NodeFailure {
+ node_id: route_hop.pubkey,
+ is_permanent: true,
+ });
+ }
+ if short_channel_id.is_none() {
+ short_channel_id = Some(route_hop.short_channel_id);
+ }
+ } else if payment_failed {
+ // Only blame the hop when a value in the HTLC doesn't match the
+ // corresponding value in the onion.
+ short_channel_id = match error_code & 0xff {
+ 18|19 => Some(route_hop.short_channel_id),
+ _ => None,
+ };
+ } else {
+ // We can't understand their error messages and they failed to
+ // forward...they probably can't understand our forwards so its
+ // really not worth trying any further.
+ network_update = Some(NetworkUpdate::NodeFailure {
+ node_id: route_hop.pubkey,
+ is_permanent: true,
+ });
+ short_channel_id = Some(route_hop.short_channel_id);
+ }
+
+ res = Some((network_update, short_channel_id, !(error_code & PERM == PERM && is_from_final_node)));
+
+ let (description, title) = errors::get_onion_error_description(error_code);
+ if debug_field_size > 0 && err_packet.failuremsg.len() >= 4 + debug_field_size {
+ log_info!(logger, "Onion Error[from {}: {}({:#x}) {}({})] {}", route_hop.pubkey, title, error_code, debug_field, log_bytes!(&err_packet.failuremsg[4..4+debug_field_size]), description);
} else {
- // only not set either packet unparseable or hmac does not match with any
- // payment not retryable only when garbage is from the final node
- (None, None, !is_from_final_node, None, None)
+ log_info!(logger, "Onion Error[from {}: {}({:#x})] {}", route_hop.pubkey, title, error_code, description);
}
- } else { unreachable!(); }
+ }).expect("Route that we sent via spontaneously grew invalid keys in the middle of it?");
+ if let Some((channel_update, short_channel_id, payment_retryable)) = res {
+ (channel_update, short_channel_id, payment_retryable, error_code_ret, error_packet_ret)
+ } else {
+ // only not set either packet unparseable or hmac does not match with any
+ // payment not retryable only when garbage is from the final node
+ (None, None, !is_from_final_node, None, None)
+ }
}
#[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
projects / rust-lightning / commitdiff