//! Creating blinded paths and related utilities live here.
pub mod payment;
-pub(crate) mod message;
+pub mod message;
pub(crate) mod utils;
use bitcoin::secp256k1::{self, PublicKey, Secp256k1, SecretKey};
use crate::routing::gossip::{NodeId, ReadOnlyNetworkGraph};
use crate::sign::EntropySource;
use crate::util::ser::{Readable, Writeable, Writer};
+use crate::util::scid_utils;
use crate::io;
use crate::prelude::*;
pub fn one_hop_for_message<ES: Deref, T: secp256k1::Signing + secp256k1::Verification>(
recipient_node_id: PublicKey, entropy_source: ES, secp_ctx: &Secp256k1<T>
) -> Result<Self, ()> where ES::Target: EntropySource {
- Self::new_for_message(&[recipient_node_id], entropy_source, secp_ctx)
+ Self::new_for_message(&[], recipient_node_id, entropy_source, secp_ctx)
}
/// Create a blinded path for an onion message, to be forwarded along `node_pks`. The last node
/// Errors if no hops are provided or if `node_pk`(s) are invalid.
// TODO: make all payloads the same size with padding + add dummy hops
pub fn new_for_message<ES: Deref, T: secp256k1::Signing + secp256k1::Verification>(
- node_pks: &[PublicKey], entropy_source: ES, secp_ctx: &Secp256k1<T>
+ intermediate_nodes: &[message::ForwardNode], recipient_node_id: PublicKey,
+ entropy_source: ES, secp_ctx: &Secp256k1<T>
) -> Result<Self, ()> where ES::Target: EntropySource {
- if node_pks.is_empty() { return Err(()) }
+ let introduction_node = IntroductionNode::NodeId(
+ intermediate_nodes.first().map_or(recipient_node_id, |n| n.node_id)
+ );
let blinding_secret_bytes = entropy_source.get_secure_random_bytes();
let blinding_secret = SecretKey::from_slice(&blinding_secret_bytes[..]).expect("RNG is busted");
- let introduction_node = IntroductionNode::NodeId(node_pks[0]);
Ok(BlindedPath {
introduction_node,
blinding_point: PublicKey::from_secret_key(secp_ctx, &blinding_secret),
- blinded_hops: message::blinded_hops(secp_ctx, node_pks, &blinding_secret).map_err(|_| ())?,
+ blinded_hops: message::blinded_hops(
+ secp_ctx, intermediate_nodes, recipient_node_id, &blinding_secret,
+ ).map_err(|_| ())?,
})
}
},
}
}
+
+ /// Attempts to a use a compact representation for the [`IntroductionNode`] by using a directed
+ /// short channel id from a channel in `network_graph` leading to the introduction node.
+ ///
+ /// While this may result in a smaller encoding, there is a trade off in that the path may
+ /// become invalid if the channel is closed or hasn't been propagated via gossip. Therefore,
+ /// calling this may not be suitable for long-lived blinded paths.
+ pub fn use_compact_introduction_node(&mut self, network_graph: &ReadOnlyNetworkGraph) {
+ if let IntroductionNode::NodeId(pubkey) = &self.introduction_node {
+ let node_id = NodeId::from_pubkey(pubkey);
+ if let Some(node_info) = network_graph.node(&node_id) {
+ if let Some((scid, channel_info)) = node_info
+ .channels
+ .iter()
+ .filter_map(|scid| network_graph.channel(*scid).map(|info| (*scid, info)))
+ .min_by_key(|(scid, _)| scid_utils::block_from_scid(*scid))
+ {
+ let direction = if node_id == channel_info.node_one {
+ Direction::NodeOne
+ } else {
+ debug_assert_eq!(node_id, channel_info.node_two);
+ Direction::NodeTwo
+ };
+ self.introduction_node =
+ IntroductionNode::DirectedShortChannelId(direction, scid);
+ }
+ }
+ }
+ }
}
impl Writeable for BlindedPath {