X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning%2Fsrc%2Fblinded_path%2Fmod.rs;h=82d50546ddd6c81f2de149333e1c30ee96754397;hb=aee7bb4acde387983c428fddcfc5b1a173cdcee7;hp=691eda29a9f3567f3e0b48b7656e07322c5866a0;hpb=9777485ed70689d55caf988b13ff7b7a0204429f;p=rust-lightning

diff --git a/lightning/src/blinded_path/mod.rs b/lightning/src/blinded_path/mod.rs
index 691eda29..82d50546 100644
--- a/lightning/src/blinded_path/mod.rs
+++ b/lightning/src/blinded_path/mod.rs
@@ -9,13 +9,15 @@
 
 //! Creating blinded paths and related utilities live here.
 
+pub mod payment;
 pub(crate) mod message;
 pub(crate) mod utils;
 
 use bitcoin::secp256k1::{self, PublicKey, Secp256k1, SecretKey};
 
-use crate::sign::EntropySource;
 use crate::ln::msgs::DecodeError;
+use crate::offers::invoice::BlindedPayInfo;
+use crate::sign::EntropySource;
 use crate::util::ser::{Readable, Writeable, Writer};
 
 use crate::io;
@@ -73,6 +75,34 @@ impl BlindedPath {
 			blinded_hops: message::blinded_hops(secp_ctx, node_pks, &blinding_secret).map_err(|_| ())?,
 		})
 	}
+
+	/// Create a blinded path for a payment, to be forwarded along `intermediate_nodes`, where each
+	/// node is composed of `(node_id, tlvs, htlc_maximum_msat)`.
+	///
+	/// Errors if:
+	/// * a provided node id is invalid
+	/// * [`BlindedPayInfo`] calculation results in an integer overflow
+	/// * any unknown features are required in the provided [`ForwardTlvs`]
+	///
+	/// [`ForwardTlvs`]: crate::blinded_path::payment::ForwardTlvs
+	//  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, u64)], payee_node_id: PublicKey,
+		payee_tlvs: payment::ReceiveTlvs, htlc_maximum_msat: u64, entropy_source: &ES,
+		secp_ctx: &Secp256k1<T>
+	) -> Result<(BlindedPayInfo, Self), ()> {
+		let blinding_secret_bytes = entropy_source.get_secure_random_bytes();
+		let blinding_secret = SecretKey::from_slice(&blinding_secret_bytes[..]).expect("RNG is busted");
+
+		let blinded_payinfo = payment::compute_payinfo(intermediate_nodes, &payee_tlvs, htlc_maximum_msat)?;
+		Ok((blinded_payinfo, 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 {