X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning%2Fsrc%2Fonion_message%2Fpacket.rs;h=5ce02c54d08800b777a0c2c3a25f27ba1ffae462;hb=ffc24c3af9a274557434a64f74ad72f338c78419;hp=a76371b39eb9fa12769e2144fb6cdd02067b70f7;hpb=bbe20c3327d3af37a7d5f82a021af1945d689547;p=rust-lightning

diff --git a/lightning/src/onion_message/packet.rs b/lightning/src/onion_message/packet.rs
index a76371b3..5ce02c54 100644
--- a/lightning/src/onion_message/packet.rs
+++ b/lightning/src/onion_message/packet.rs
@@ -32,16 +32,22 @@ use crate::prelude::*;
 pub(super) const SMALL_PACKET_HOP_DATA_LEN: usize = 1300;
 pub(super) const BIG_PACKET_HOP_DATA_LEN: usize = 32768;
 
-#[derive(Clone, Debug, PartialEq, Eq)]
-pub(crate) struct Packet {
-	pub(super) version: u8,
-	pub(super) public_key: PublicKey,
+/// Packet of hop data for next peer
+#[derive(Clone, Debug, Hash, PartialEq, Eq)]
+pub struct Packet {
+	/// Bolt 04 version number
+	pub version: u8,
+	/// A random sepc256k1 point, used to build the ECDH shared secret to decrypt hop_data
+	pub public_key: PublicKey,
+	/// Encrypted payload for the next hop
+	//
 	// Unlike the onion packets used for payments, onion message packets can have payloads greater
 	// than 1300 bytes.
 	// TODO: if 1300 ends up being the most common size, optimize this to be:
 	// enum { ThirteenHundred([u8; 1300]), VarLen(Vec<u8>) }
-	pub(super) hop_data: Vec<u8>,
-	pub(super) hmac: [u8; 32],
+	pub hop_data: Vec<u8>,
+	/// HMAC to verify the integrity of hop_data
+	pub hmac: [u8; 32],
 }
 
 impl onion_utils::Packet for Packet {
@@ -97,51 +103,51 @@ impl LengthReadable for Packet {
 /// Onion message payloads contain "control" TLVs and "data" TLVs. Control TLVs are used to route
 /// the onion message from hop to hop and for path verification, whereas data TLVs contain the onion
 /// message content itself, such as an invoice request.
-pub(super) enum Payload<T: CustomOnionMessageContents> {
+pub(super) enum Payload<T: OnionMessageContents> {
 	/// This payload is for an intermediate hop.
 	Forward(ForwardControlTlvs),
 	/// This payload is for the final hop.
 	Receive {
 		control_tlvs: ReceiveControlTlvs,
 		reply_path: Option<BlindedPath>,
-		message: OnionMessageContents<T>,
+		message: T,
 	}
 }
 
+/// The contents of an [`OnionMessage`] as read from the wire.
+///
+/// [`OnionMessage`]: crate::ln::msgs::OnionMessage
 #[derive(Debug)]
-/// The contents of an onion message. In the context of offers, this would be the invoice, invoice
-/// request, or invoice error.
-pub enum OnionMessageContents<T: CustomOnionMessageContents> {
+pub enum ParsedOnionMessageContents<T: OnionMessageContents> {
 	/// A message related to BOLT 12 Offers.
 	Offers(OffersMessage),
 	/// A custom onion message specified by the user.
 	Custom(T),
 }
 
-impl<T: CustomOnionMessageContents> OnionMessageContents<T> {
+impl<T: OnionMessageContents> OnionMessageContents for ParsedOnionMessageContents<T> {
 	/// Returns the type that was used to decode the message payload.
 	///
 	/// This is not exported to bindings users as methods on non-cloneable enums are not currently exportable
-	pub fn tlv_type(&self) -> u64 {
+	fn tlv_type(&self) -> u64 {
 		match self {
-			&OnionMessageContents::Offers(ref msg) => msg.tlv_type(),
-			&OnionMessageContents::Custom(ref msg) => msg.tlv_type(),
+			&ParsedOnionMessageContents::Offers(ref msg) => msg.tlv_type(),
+			&ParsedOnionMessageContents::Custom(ref msg) => msg.tlv_type(),
 		}
 	}
 }
 
-/// This is not exported to bindings users as methods on non-cloneable enums are not currently exportable
-impl<T: CustomOnionMessageContents> Writeable for OnionMessageContents<T> {
+impl<T: OnionMessageContents> Writeable for ParsedOnionMessageContents<T> {
 	fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 		match self {
-			OnionMessageContents::Offers(msg) => Ok(msg.write(w)?),
-			OnionMessageContents::Custom(msg) => Ok(msg.write(w)?),
+			ParsedOnionMessageContents::Offers(msg) => Ok(msg.write(w)?),
+			ParsedOnionMessageContents::Custom(msg) => Ok(msg.write(w)?),
 		}
 	}
 }
 
-/// The contents of a custom onion message.
-pub trait CustomOnionMessageContents: Writeable {
+/// The contents of an onion message.
+pub trait OnionMessageContents: Writeable + core::fmt::Debug {
 	/// Returns the TLV type identifying the message contents. MUST be >= 64.
 	fn tlv_type(&self) -> u64;
 }
@@ -167,7 +173,7 @@ pub(super) enum ReceiveControlTlvs {
 }
 
 // Uses the provided secret to simultaneously encode and encrypt the unblinded control TLVs.
-impl<T: CustomOnionMessageContents> Writeable for (Payload<T>, [u8; 32]) {
+impl<T: OnionMessageContents> Writeable for (Payload<T>, [u8; 32]) {
 	fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 		match &self.0 {
 			Payload::Forward(ForwardControlTlvs::Blinded(encrypted_bytes)) => {
@@ -206,8 +212,8 @@ impl<T: CustomOnionMessageContents> Writeable for (Payload<T>, [u8; 32]) {
 }
 
 // Uses the provided secret to simultaneously decode and decrypt the control TLVs and data TLV.
-impl<H: CustomOnionMessageHandler + ?Sized, L: Logger + ?Sized>
-ReadableArgs<(SharedSecret, &H, &L)> for Payload<<H as CustomOnionMessageHandler>::CustomMessage> {
+impl<H: CustomOnionMessageHandler + ?Sized, L: Logger + ?Sized> ReadableArgs<(SharedSecret, &H, &L)>
+for Payload<ParsedOnionMessageContents<<H as CustomOnionMessageHandler>::CustomMessage>> {
 	fn read<R: Read>(r: &mut R, args: (SharedSecret, &H, &L)) -> Result<Self, DecodeError> {
 		let (encrypted_tlvs_ss, handler, logger) = args;
 
@@ -230,12 +236,12 @@ ReadableArgs<(SharedSecret, &H, &L)> for Payload<<H as CustomOnionMessageHandler
 			match msg_type {
 				tlv_type if OffersMessage::is_known_type(tlv_type) => {
 					let msg = OffersMessage::read(msg_reader, (tlv_type, logger))?;
-					message = Some(OnionMessageContents::Offers(msg));
+					message = Some(ParsedOnionMessageContents::Offers(msg));
 					Ok(true)
 				},
 				_ => match handler.read_custom_message(msg_type, msg_reader)? {
 					Some(msg) => {
-						message = Some(OnionMessageContents::Custom(msg));
+						message = Some(ParsedOnionMessageContents::Custom(msg));
 						Ok(true)
 					},
 					None => Ok(false),