From: Valentine Wallace Date: Thu, 13 Jul 2023 02:32:06 +0000 (-0400) Subject: Support paying blinded paths. X-Git-Tag: v0.0.117-alpha1~14^2~4 X-Git-Url: http://git.bitcoin.ninja/?a=commitdiff_plain;h=7b1e09134afd256aa3a5465b51cac90bf9e2ab00;p=rust-lightning Support paying blinded paths. --- diff --git a/lightning/src/ln/msgs.rs b/lightning/src/ln/msgs.rs index 6bd5ec3f7..8bb264fe9 100644 --- a/lightning/src/ln/msgs.rs +++ b/lightning/src/ln/msgs.rs @@ -1517,6 +1517,7 @@ pub trait OnionMessageHandler : OnionMessageProvider { } mod fuzzy_internal_msgs { + use bitcoin::secp256k1::PublicKey; use crate::prelude::*; use crate::ln::{PaymentPreimage, PaymentSecret}; @@ -1562,6 +1563,17 @@ mod fuzzy_internal_msgs { amt_msat: u64, outgoing_cltv_value: u32, }, + BlindedForward { + encrypted_tlvs: Vec, + intro_node_blinding_point: Option, + }, + BlindedReceive { + amt_msat: u64, + total_msat: u64, + outgoing_cltv_value: u32, + encrypted_tlvs: Vec, + intro_node_blinding_point: Option, // Set if the introduction node of the blinded path is the final node + } } pub struct DecodedOnionErrorPacket { @@ -2097,6 +2109,24 @@ impl Writeable for OutboundOnionPayload { (16, payment_metadata.as_ref().map(|m| WithoutLength(m)), option) }, custom_tlvs.iter()); }, + Self::BlindedForward { encrypted_tlvs, intro_node_blinding_point } => { + _encode_varint_length_prefixed_tlv!(w, { + (10, *encrypted_tlvs, required_vec), + (12, intro_node_blinding_point, option) + }); + }, + Self::BlindedReceive { + amt_msat, total_msat, outgoing_cltv_value, encrypted_tlvs, + intro_node_blinding_point, + } => { + _encode_varint_length_prefixed_tlv!(w, { + (2, HighZeroBytesDroppedBigSize(*amt_msat), required), + (4, HighZeroBytesDroppedBigSize(*outgoing_cltv_value), required), + (10, *encrypted_tlvs, required_vec), + (12, intro_node_blinding_point, option), + (18, HighZeroBytesDroppedBigSize(*total_msat), required) + }); + }, } Ok(()) } diff --git a/lightning/src/ln/onion_utils.rs b/lightning/src/ln/onion_utils.rs index 8fdbdefef..8782323ea 100644 --- a/lightning/src/ln/onion_utils.rs +++ b/lightning/src/ln/onion_utils.rs @@ -12,7 +12,7 @@ use crate::ln::channelmanager::{HTLCSource, RecipientOnionFields}; use crate::ln::msgs; use crate::ln::wire::Encode; use crate::routing::gossip::NetworkUpdate; -use crate::routing::router::{Path, RouteHop}; +use crate::routing::router::{BlindedTail, Path, RouteHop}; use crate::util::chacha20::{ChaCha20, ChaChaReader}; use crate::util::errors::{self, APIError}; use crate::util::ser::{Readable, ReadableArgs, Writeable, Writer, LengthCalculatingWriter}; @@ -169,7 +169,9 @@ pub(super) fn build_onion_payloads(path: &Path, total_msat: u64, mut recipient_o let mut cur_value_msat = 0u64; let mut cur_cltv = starting_htlc_offset; let mut last_short_channel_id = 0; - let mut res: Vec = Vec::with_capacity(path.hops.len()); + let mut res: Vec = Vec::with_capacity( + path.hops.len() + path.blinded_tail.as_ref().map_or(0, |t| t.hops.len()) + ); for (idx, hop) in path.hops.iter().rev().enumerate() { // First hop gets special values so that it can check, on receipt, that everything is @@ -177,27 +179,51 @@ pub(super) fn build_onion_payloads(path: &Path, total_msat: u64, mut recipient_o // the intended recipient). let value_msat = if cur_value_msat == 0 { hop.fee_msat } else { cur_value_msat }; let cltv = if cur_cltv == starting_htlc_offset { hop.cltv_expiry_delta + starting_htlc_offset } else { cur_cltv }; - res.insert(0, if idx == 0 { - msgs::OutboundOnionPayload::Receive { - payment_data: if let Some(secret) = recipient_onion.payment_secret.take() { - Some(msgs::FinalOnionHopData { - payment_secret: secret, - total_msat, - }) - } else { None }, - payment_metadata: recipient_onion.payment_metadata.take(), - keysend_preimage: *keysend_preimage, - custom_tlvs: recipient_onion.custom_tlvs.clone(), - amt_msat: value_msat, - outgoing_cltv_value: cltv, + if idx == 0 { + if let Some(BlindedTail { + blinding_point, hops, final_value_msat, excess_final_cltv_expiry_delta, .. + }) = &path.blinded_tail { + let mut blinding_point = Some(*blinding_point); + for (i, blinded_hop) in hops.iter().enumerate() { + if i == hops.len() - 1 { + cur_value_msat += final_value_msat; + cur_cltv += excess_final_cltv_expiry_delta; + res.push(msgs::OutboundOnionPayload::BlindedReceive { + amt_msat: *final_value_msat, + total_msat, + outgoing_cltv_value: cltv, + encrypted_tlvs: blinded_hop.encrypted_payload.clone(), + intro_node_blinding_point: blinding_point.take(), + }); + } else { + res.push(msgs::OutboundOnionPayload::BlindedForward { + encrypted_tlvs: blinded_hop.encrypted_payload.clone(), + intro_node_blinding_point: blinding_point.take(), + }); + } + } + } else { + res.push(msgs::OutboundOnionPayload::Receive { + payment_data: if let Some(secret) = recipient_onion.payment_secret.take() { + Some(msgs::FinalOnionHopData { + payment_secret: secret, + total_msat, + }) + } else { None }, + payment_metadata: recipient_onion.payment_metadata.take(), + keysend_preimage: *keysend_preimage, + custom_tlvs: recipient_onion.custom_tlvs.clone(), + amt_msat: value_msat, + outgoing_cltv_value: cltv, + }); } } else { - msgs::OutboundOnionPayload::Forward { + res.insert(0, msgs::OutboundOnionPayload::Forward { short_channel_id: last_short_channel_id, amt_to_forward: value_msat, outgoing_cltv_value: cltv, - } - }); + }); + } cur_value_msat += hop.fee_msat; if cur_value_msat >= 21000000 * 100000000 * 1000 { return Err(APIError::InvalidRoute{err: "Channel fees overflowed?".to_owned()}); diff --git a/lightning/src/ln/outbound_payment.rs b/lightning/src/ln/outbound_payment.rs index 0cc9e7e05..5ea772e5d 100644 --- a/lightning/src/ln/outbound_payment.rs +++ b/lightning/src/ln/outbound_payment.rs @@ -1234,7 +1234,9 @@ impl OutboundPayments { if route.paths.len() < 1 { return Err(PaymentSendFailure::ParameterError(APIError::InvalidRoute{err: "There must be at least one path to send over".to_owned()})); } - if recipient_onion.payment_secret.is_none() && route.paths.len() > 1 { + if recipient_onion.payment_secret.is_none() && route.paths.len() > 1 + && !route.paths.iter().any(|p| p.blinded_tail.is_some()) + { return Err(PaymentSendFailure::ParameterError(APIError::APIMisuseError{err: "Payment secret is required for multi-path payments".to_owned()})); } let mut total_value = 0; @@ -1245,10 +1247,6 @@ impl OutboundPayments { path_errs.push(Err(APIError::InvalidRoute{err: "Path didn't go anywhere/had bogus size".to_owned()})); continue 'path_check; } - if path.blinded_tail.is_some() { - path_errs.push(Err(APIError::InvalidRoute{err: "Sending to blinded paths isn't supported yet".to_owned()})); - continue 'path_check; - } let dest_hop_idx = if path.blinded_tail.is_some() && path.blinded_tail.as_ref().unwrap().hops.len() > 1 { usize::max_value() } else { path.hops.len() - 1 }; for (idx, hop) in path.hops.iter().enumerate() {