use crate::ln::onion_payment::{check_incoming_htlc_cltv, create_recv_pending_htlc_info, create_fwd_pending_htlc_info, decode_incoming_update_add_htlc_onion, InboundOnionErr, NextPacketDetails};
use crate::ln::msgs;
use crate::ln::onion_utils;
-use crate::ln::onion_utils::HTLCFailReason;
+use crate::ln::onion_utils::{HTLCFailReason, INVALID_ONION_BLINDING};
use crate::ln::msgs::{ChannelMessageHandler, DecodeError, LightningError};
#[cfg(test)]
use crate::ln::outbound_payment;
/// The SCID from the onion that we should forward to. This could be a real SCID or a fake one
/// generated using `get_fake_scid` from the scid_utils::fake_scid module.
short_channel_id: u64, // This should be NonZero<u64> eventually when we bump MSRV
+ /// Set if this HTLC is being forwarded within a blinded path.
+ blinded: Option<BlindedForward>,
},
/// An HTLC paid to an invoice (supposedly) generated by us.
/// At this point, we have not checked that the invoice being paid was actually generated by us,
},
}
+/// Information used to forward or fail this HTLC that is being forwarded within a blinded path.
+#[derive(Clone, Copy, Hash, PartialEq, Eq)]
+pub struct BlindedForward {
+ /// The `blinding_point` that was set in the inbound [`msgs::UpdateAddHTLC`], or in the inbound
+ /// onion payload if we're the introduction node. Useful for calculating the next hop's
+ /// [`msgs::UpdateAddHTLC::blinding_point`].
+ pub inbound_blinding_point: PublicKey,
+ // Another field will be added here when we support forwarding as a non-intro node.
+}
+
+impl PendingHTLCRouting {
+ // Used to override the onion failure code and data if the HTLC is blinded.
+ fn blinded_failure(&self) -> Option<BlindedFailure> {
+ // TODO: needs update when we support receiving to multi-hop blinded paths
+ if let Self::Forward { blinded: Some(_), .. } = self {
+ Some(BlindedFailure::FromIntroductionNode)
+ } else {
+ None
+ }
+ }
+}
+
/// Full details of an incoming HTLC, including routing info.
#[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
pub struct PendingHTLCInfo {
},
}
+// Used for failing blinded HTLCs backwards correctly.
+#[derive(Clone, Debug, Hash, PartialEq, Eq)]
+enum BlindedFailure {
+ FromIntroductionNode,
+ // Another variant will be added here for non-intro nodes.
+}
+
/// Tracks the inbound corresponding to an outbound HTLC
#[derive(Clone, Debug, Hash, PartialEq, Eq)]
pub(crate) struct HTLCPreviousHopData {
htlc_id: u64,
incoming_packet_shared_secret: [u8; 32],
phantom_shared_secret: Option<[u8; 32]>,
+ blinded_failure: Option<BlindedFailure>,
// This field is consumed by `claim_funds_from_hop()` when updating a force-closed backwards
// channel with a preimage provided by the forward channel.
msg, &self.node_signer, &self.logger, &self.secp_ctx
)?;
+ let is_blinded = match next_hop {
+ onion_utils::Hop::Forward {
+ next_hop_data: msgs::InboundOnionPayload::BlindedForward { .. }, ..
+ } => true,
+ _ => false, // TODO: update this when we support receiving to multi-hop blinded paths
+ };
+
macro_rules! return_err {
($msg: expr, $err_code: expr, $data: expr) => {
{
log_info!(self.logger, "Failed to accept/forward incoming HTLC: {}", $msg);
+ let (err_code, err_data) = if is_blinded {
+ (INVALID_ONION_BLINDING, &[0; 32][..])
+ } else { ($err_code, $data) };
return Err(HTLCFailureMsg::Relay(msgs::UpdateFailHTLC {
channel_id: msg.channel_id,
htlc_id: msg.htlc_id,
- reason: HTLCFailReason::reason($err_code, $data.to_vec())
+ reason: HTLCFailReason::reason(err_code, err_data.to_vec())
.get_encrypted_failure_packet(&shared_secret, &None),
}));
}
})?;
let routing = match payment.forward_info.routing {
- PendingHTLCRouting::Forward { onion_packet, .. } => {
- PendingHTLCRouting::Forward { onion_packet, short_channel_id: next_hop_scid }
+ PendingHTLCRouting::Forward { onion_packet, blinded, .. } => {
+ PendingHTLCRouting::Forward {
+ onion_packet, blinded, short_channel_id: next_hop_scid
+ }
},
_ => unreachable!() // Only `PendingHTLCRouting::Forward`s are intercepted
};
htlc_id: payment.prev_htlc_id,
incoming_packet_shared_secret: payment.forward_info.incoming_shared_secret,
phantom_shared_secret: None,
+ blinded_failure: payment.forward_info.routing.blinded_failure(),
});
let failure_reason = HTLCFailReason::from_failure_code(0x4000 | 10);
htlc_id: prev_htlc_id,
incoming_packet_shared_secret: incoming_shared_secret,
phantom_shared_secret: $phantom_ss,
+ blinded_failure: routing.blinded_failure(),
});
let reason = if $next_hop_unknown {
}
}
}
- if let PendingHTLCRouting::Forward { onion_packet, .. } = routing {
+ if let PendingHTLCRouting::Forward { ref onion_packet, .. } = routing {
let phantom_pubkey_res = self.node_signer.get_node_id(Recipient::PhantomNode);
if phantom_pubkey_res.is_ok() && fake_scid::is_valid_phantom(&self.fake_scid_rand_bytes, short_chan_id, &self.chain_hash) {
let phantom_shared_secret = self.node_signer.ecdh(Recipient::PhantomNode, &onion_packet.public_key.unwrap(), None).unwrap().secret_bytes();
prev_short_channel_id, prev_htlc_id, prev_funding_outpoint, prev_user_channel_id,
forward_info: PendingHTLCInfo {
incoming_shared_secret, payment_hash, outgoing_amt_msat, outgoing_cltv_value,
- routing: PendingHTLCRouting::Forward { onion_packet, .. }, skimmed_fee_msat, ..
+ routing: PendingHTLCRouting::Forward {
+ onion_packet, blinded, ..
+ }, skimmed_fee_msat, ..
},
}) => {
log_trace!(self.logger, "Adding HTLC from short id {} with payment_hash {} to channel with short id {} after delay", prev_short_channel_id, &payment_hash, short_chan_id);
incoming_packet_shared_secret: incoming_shared_secret,
// Phantom payments are only PendingHTLCRouting::Receive.
phantom_shared_secret: None,
+ blinded_failure: blinded.map(|_| BlindedFailure::FromIntroductionNode),
+ });
+ let next_blinding_point = blinded.and_then(|b| {
+ let encrypted_tlvs_ss = self.node_signer.ecdh(
+ Recipient::Node, &b.inbound_blinding_point, None
+ ).unwrap().secret_bytes();
+ onion_utils::next_hop_pubkey(
+ &self.secp_ctx, b.inbound_blinding_point, &encrypted_tlvs_ss
+ ).ok()
});
if let Err(e) = chan.queue_add_htlc(outgoing_amt_msat,
payment_hash, outgoing_cltv_value, htlc_source.clone(),
- onion_packet, skimmed_fee_msat, &self.fee_estimator,
+ onion_packet, skimmed_fee_msat, next_blinding_point, &self.fee_estimator,
&self.logger)
{
if let ChannelError::Ignore(msg) = e {
skimmed_fee_msat, ..
}
}) => {
+ let blinded_failure = routing.blinded_failure();
let (cltv_expiry, onion_payload, payment_data, phantom_shared_secret, mut onion_fields) = match routing {
PendingHTLCRouting::Receive { payment_data, payment_metadata, incoming_cltv_expiry, phantom_shared_secret, custom_tlvs } => {
let _legacy_hop_data = Some(payment_data.clone());
htlc_id: prev_htlc_id,
incoming_packet_shared_secret: incoming_shared_secret,
phantom_shared_secret,
+ blinded_failure,
},
// We differentiate the received value from the sender intended value
// if possible so that we don't prematurely mark MPP payments complete
htlc_id: $htlc.prev_hop.htlc_id,
incoming_packet_shared_secret: $htlc.prev_hop.incoming_packet_shared_secret,
phantom_shared_secret,
+ blinded_failure: None,
}), payment_hash,
HTLCFailReason::reason(0x4000 | 15, htlc_msat_height_data),
HTLCDestination::FailedPayment { payment_hash: $payment_hash },
&self.pending_events, &self.logger)
{ self.push_pending_forwards_ev(); }
},
- HTLCSource::PreviousHopData(HTLCPreviousHopData { ref short_channel_id, ref htlc_id, ref incoming_packet_shared_secret, ref phantom_shared_secret, ref outpoint, .. }) => {
- log_trace!(self.logger, "Failing HTLC with payment_hash {} backwards from us with {:?}", &payment_hash, onion_error);
- let err_packet = onion_error.get_encrypted_failure_packet(incoming_packet_shared_secret, phantom_shared_secret);
+ HTLCSource::PreviousHopData(HTLCPreviousHopData {
+ ref short_channel_id, ref htlc_id, ref incoming_packet_shared_secret,
+ ref phantom_shared_secret, ref outpoint, ref blinded_failure, ..
+ }) => {
+ log_trace!(self.logger, "Failing {}HTLC with payment_hash {} backwards from us: {:?}",
+ if blinded_failure.is_some() { "blinded " } else { "" }, &payment_hash, onion_error);
+ let err_packet = match blinded_failure {
+ Some(BlindedFailure::FromIntroductionNode) => {
+ let blinded_onion_error = HTLCFailReason::reason(INVALID_ONION_BLINDING, vec![0; 32]);
+ blinded_onion_error.get_encrypted_failure_packet(
+ incoming_packet_shared_secret, phantom_shared_secret
+ )
+ },
+ None => {
+ onion_error.get_encrypted_failure_packet(incoming_packet_shared_secret, phantom_shared_secret)
+ }
+ };
let mut push_forward_ev = false;
let mut forward_htlcs = self.forward_htlcs.lock().unwrap();
// but if we've sent a shutdown and they haven't acknowledged it yet, we just
// want to reject the new HTLC and fail it backwards instead of forwarding.
match pending_forward_info {
- PendingHTLCStatus::Forward(PendingHTLCInfo { ref incoming_shared_secret, .. }) => {
- let reason = if (error_code & 0x1000) != 0 {
+ PendingHTLCStatus::Forward(PendingHTLCInfo {
+ ref incoming_shared_secret, ref routing, ..
+ }) => {
+ let reason = if routing.blinded_failure().is_some() {
+ HTLCFailReason::reason(INVALID_ONION_BLINDING, vec![0; 32])
+ } else if (error_code & 0x1000) != 0 {
let (real_code, error_data) = self.get_htlc_inbound_temp_fail_err_and_data(error_code, chan);
HTLCFailReason::reason(real_code, error_data)
} else {
htlc_id: prev_htlc_id,
incoming_packet_shared_secret: forward_info.incoming_shared_secret,
phantom_shared_secret: None,
+ blinded_failure: forward_info.routing.blinded_failure(),
});
failed_intercept_forwards.push((htlc_source, forward_info.payment_hash,
incoming_packet_shared_secret: htlc.forward_info.incoming_shared_secret,
phantom_shared_secret: None,
outpoint: htlc.prev_funding_outpoint,
+ blinded_failure: htlc.forward_info.routing.blinded_failure(),
});
let requested_forward_scid /* intercept scid */ = match htlc.forward_info.routing {
(6, real_node_pubkey, required),
});
+impl_writeable_tlv_based!(BlindedForward, {
+ (0, inbound_blinding_point, required),
+});
+
impl_writeable_tlv_based_enum!(PendingHTLCRouting,
(0, Forward) => {
(0, onion_packet, required),
+ (1, blinded, option),
(2, short_channel_id, required),
},
(1, Receive) => {
(1, Fail),
);
+impl_writeable_tlv_based_enum!(BlindedFailure,
+ (0, FromIntroductionNode) => {}, ;
+);
+
impl_writeable_tlv_based!(HTLCPreviousHopData, {
(0, short_channel_id, required),
(1, phantom_shared_secret, option),
(2, outpoint, required),
+ (3, blinded_failure, option),
(4, htlc_id, required),
(6, incoming_packet_shared_secret, required),
(7, user_channel_id, option),