//! Creating blinded paths and related utilities live here.
+pub mod payment;
pub(crate) mod message;
pub(crate) mod utils;
pub blinded_hops: Vec<BlindedHop>,
}
-/// Used to construct the blinded hops portion of a blinded path. These hops cannot be identified
-/// by outside observers and thus can be used to hide the identity of the recipient.
+/// An encrypted payload and node id corresponding to a hop in a payment or onion message path, to
+/// be encoded in the sender's onion packet. These hops cannot be identified by outside observers
+/// and thus can be used to hide the identity of the recipient.
#[derive(Clone, Debug, Hash, PartialEq, Eq)]
pub struct BlindedHop {
- /// The blinded node id of this hop in a blinded path.
+ /// The blinded node id of this hop in a [`BlindedPath`].
pub blinded_node_id: PublicKey,
- /// The encrypted payload intended for this hop in a blinded path.
+ /// The encrypted payload intended for this hop in a [`BlindedPath`].
// The node sending to this blinded path will later encode this payload into the onion packet for
// this hop.
pub encrypted_payload: Vec<u8>,
blinded_hops: message::blinded_hops(secp_ctx, node_pks, &blinding_secret).map_err(|_| ())?,
})
}
+
+ /// Create a blinded path for a payment, to be forwarded along `path`. The last node
+ /// in `path` will be the destination node.
+ ///
+ /// Errors if `path` is empty or a node id in `path` is invalid.
+ // TODO: make all payloads the same size with padding + add dummy hops
+ pub fn new_for_payment<ES: EntropySource, T: secp256k1::Signing + secp256k1::Verification>(
+ intermediate_nodes: &[(PublicKey, payment::ForwardTlvs)], payee_node_id: PublicKey,
+ payee_tlvs: payment::ReceiveTlvs, entropy_source: &ES, secp_ctx: &Secp256k1<T>
+ ) -> Result<Self, ()> {
+ let blinding_secret_bytes = entropy_source.get_secure_random_bytes();
+ let blinding_secret = SecretKey::from_slice(&blinding_secret_bytes[..]).expect("RNG is busted");
+
+ Ok(BlindedPath {
+ introduction_node_id: intermediate_nodes.first().map_or(payee_node_id, |n| n.0),
+ blinding_point: PublicKey::from_secret_key(secp_ctx, &blinding_secret),
+ blinded_hops: payment::blinded_hops(
+ secp_ctx, intermediate_nodes, payee_node_id, payee_tlvs, &blinding_secret
+ ).map_err(|_| ())?,
+ })
+ }
}
impl Writeable for BlindedPath {