}
}
+struct ReceiveError {
+ err_code: u16,
+ err_data: Vec<u8>,
+ msg: &'static str,
+}
+
/// Return value for claim_funds_from_hop
enum ClaimFundsFromHop {
PrevHopForceClosed,
}
}
+ fn construct_recv_pending_htlc_info(&self, hop_data: msgs::OnionHopData, shared_secret: [u8; 32],
+ payment_hash: PaymentHash, amt_msat: u64, cltv_expiry: u32) -> Result<PendingHTLCInfo, ReceiveError>
+ {
+ // final_incorrect_cltv_expiry
+ if hop_data.outgoing_cltv_value != cltv_expiry {
+ return Err(ReceiveError {
+ msg: "Upstream node set CLTV to the wrong value",
+ err_code: 18,
+ err_data: byte_utils::be32_to_array(cltv_expiry).to_vec()
+ })
+ }
+ // final_expiry_too_soon
+ // We have to have some headroom to broadcast on chain if we have the preimage, so make sure
+ // we have at least HTLC_FAIL_BACK_BUFFER blocks to go.
+ // Also, ensure that, in the case of an unknown preimage for the received payment hash, our
+ // payment logic has enough time to fail the HTLC backward before our onchain logic triggers a
+ // channel closure (see HTLC_FAIL_BACK_BUFFER rationale).
+ if (hop_data.outgoing_cltv_value as u64) <= self.best_block.read().unwrap().height() as u64 + HTLC_FAIL_BACK_BUFFER as u64 + 1 {
+ return Err(ReceiveError {
+ err_code: 17,
+ err_data: Vec::new(),
+ msg: "The final CLTV expiry is too soon to handle",
+ });
+ }
+ if hop_data.amt_to_forward > amt_msat {
+ return Err(ReceiveError {
+ err_code: 19,
+ err_data: byte_utils::be64_to_array(amt_msat).to_vec(),
+ msg: "Upstream node sent less than we were supposed to receive in payment",
+ });
+ }
+
+ let routing = match hop_data.format {
+ msgs::OnionHopDataFormat::Legacy { .. } => {
+ return Err(ReceiveError {
+ err_code: 0x4000|0x2000|3,
+ err_data: Vec::new(),
+ msg: "We require payment_secrets",
+ });
+ },
+ msgs::OnionHopDataFormat::NonFinalNode { .. } => {
+ return Err(ReceiveError {
+ err_code: 0x4000|22,
+ err_data: Vec::new(),
+ msg: "Got non final data with an HMAC of 0",
+ });
+ },
+ msgs::OnionHopDataFormat::FinalNode { payment_data, keysend_preimage } => {
+ if payment_data.is_some() && keysend_preimage.is_some() {
+ return Err(ReceiveError {
+ err_code: 0x4000|22,
+ err_data: Vec::new(),
+ msg: "We don't support MPP keysend payments",
+ });
+ } else if let Some(data) = payment_data {
+ PendingHTLCRouting::Receive {
+ payment_data: data,
+ incoming_cltv_expiry: hop_data.outgoing_cltv_value,
+ }
+ } else if let Some(payment_preimage) = keysend_preimage {
+ // We need to check that the sender knows the keysend preimage before processing this
+ // payment further. Otherwise, an intermediary routing hop forwarding non-keysend-HTLC X
+ // could discover the final destination of X, by probing the adjacent nodes on the route
+ // with a keysend payment of identical payment hash to X and observing the processing
+ // time discrepancies due to a hash collision with X.
+ let hashed_preimage = PaymentHash(Sha256::hash(&payment_preimage.0).into_inner());
+ if hashed_preimage != payment_hash {
+ return Err(ReceiveError {
+ err_code: 0x4000|22,
+ err_data: Vec::new(),
+ msg: "Payment preimage didn't match payment hash",
+ });
+ }
+
+ PendingHTLCRouting::ReceiveKeysend {
+ payment_preimage,
+ incoming_cltv_expiry: hop_data.outgoing_cltv_value,
+ }
+ } else {
+ return Err(ReceiveError {
+ err_code: 0x4000|0x2000|3,
+ err_data: Vec::new(),
+ msg: "We require payment_secrets",
+ });
+ }
+ },
+ };
+ Ok(PendingHTLCInfo {
+ routing,
+ payment_hash,
+ incoming_shared_secret: shared_secret,
+ amt_to_forward: amt_msat,
+ outgoing_cltv_value: hop_data.outgoing_cltv_value,
+ })
+ }
+
fn decode_update_add_htlc_onion(&self, msg: &msgs::UpdateAddHTLC) -> (PendingHTLCStatus, MutexGuard<ChannelHolder<Signer>>) {
macro_rules! return_malformed_err {
($msg: expr, $err_code: expr) => {
let pending_forward_info = match next_hop {
onion_utils::Hop::Receive(next_hop_data) => {
// OUR PAYMENT!
- // final_expiry_too_soon
- // We have to have some headroom to broadcast on chain if we have the preimage, so make sure
- // we have at least HTLC_FAIL_BACK_BUFFER blocks to go.
- // Also, ensure that, in the case of an unknown preimage for the received payment hash, our
- // payment logic has enough time to fail the HTLC backward before our onchain logic triggers a
- // channel closure (see HTLC_FAIL_BACK_BUFFER rationale).
- if (msg.cltv_expiry as u64) <= self.best_block.read().unwrap().height() as u64 + HTLC_FAIL_BACK_BUFFER as u64 + 1 {
- return_err!("The final CLTV expiry is too soon to handle", 17, &[0;0]);
- }
- // final_incorrect_htlc_amount
- if next_hop_data.amt_to_forward > msg.amount_msat {
- return_err!("Upstream node sent less than we were supposed to receive in payment", 19, &byte_utils::be64_to_array(msg.amount_msat));
- }
- // final_incorrect_cltv_expiry
- if next_hop_data.outgoing_cltv_value != msg.cltv_expiry {
- return_err!("Upstream node set CLTV to the wrong value", 18, &byte_utils::be32_to_array(msg.cltv_expiry));
- }
-
- let routing = match next_hop_data.format {
- msgs::OnionHopDataFormat::Legacy { .. } => return_err!("We require payment_secrets", 0x4000|0x2000|3, &[0;0]),
- msgs::OnionHopDataFormat::NonFinalNode { .. } => return_err!("Got non final data with an HMAC of 0", 0x4000 | 22, &[0;0]),
- msgs::OnionHopDataFormat::FinalNode { payment_data, keysend_preimage } => {
- if payment_data.is_some() && keysend_preimage.is_some() {
- return_err!("We don't support MPP keysend payments", 0x4000|22, &[0;0]);
- } else if let Some(data) = payment_data {
- PendingHTLCRouting::Receive {
- payment_data: data,
- incoming_cltv_expiry: msg.cltv_expiry,
- }
- } else if let Some(payment_preimage) = keysend_preimage {
- // We need to check that the sender knows the keysend preimage before processing this
- // payment further. Otherwise, an intermediary routing hop forwarding non-keysend-HTLC X
- // could discover the final destination of X, by probing the adjacent nodes on the route
- // with a keysend payment of identical payment hash to X and observing the processing
- // time discrepancies due to a hash collision with X.
- let hashed_preimage = PaymentHash(Sha256::hash(&payment_preimage.0).into_inner());
- if hashed_preimage != msg.payment_hash {
- return_err!("Payment preimage didn't match payment hash", 0x4000|22, &[0;0]);
- }
-
- PendingHTLCRouting::ReceiveKeysend {
- payment_preimage,
- incoming_cltv_expiry: msg.cltv_expiry,
- }
- } else {
- return_err!("We require payment_secrets", 0x4000|0x2000|3, &[0;0]);
- }
+ match self.construct_recv_pending_htlc_info(next_hop_data, shared_secret, msg.payment_hash, msg.amount_msat, msg.cltv_expiry) {
+ Ok(info) => {
+ // Note that we could obviously respond immediately with an update_fulfill_htlc
+ // message, however that would leak that we are the recipient of this payment, so
+ // instead we stay symmetric with the forwarding case, only responding (after a
+ // delay) once they've send us a commitment_signed!
+ PendingHTLCStatus::Forward(info)
},
- };
-
- // Note that we could obviously respond immediately with an update_fulfill_htlc
- // message, however that would leak that we are the recipient of this payment, so
- // instead we stay symmetric with the forwarding case, only responding (after a
- // delay) once they've send us a commitment_signed!
-
- PendingHTLCStatus::Forward(PendingHTLCInfo {
- routing,
- payment_hash: msg.payment_hash.clone(),
- incoming_shared_secret: shared_secret,
- amt_to_forward: next_hop_data.amt_to_forward,
- outgoing_cltv_value: next_hop_data.outgoing_cltv_value,
- })
+ Err(ReceiveError { err_code, err_data, msg }) => return_err!(msg, err_code, &err_data)
+ }
},
onion_utils::Hop::Forward { next_hop_data, next_hop_hmac, new_packet_bytes } => {
let mut new_pubkey = msg.onion_routing_packet.public_key.unwrap();