Hide OnionV2 struct detail

Author: yanganto

lightning/src/ln/msgs.rs

@@ -774,13 +774,8 @@ pub enum SocketAddress {
 	/// An old-style Tor onion address/port on which the peer is listening.
 	///
 	/// This field is deprecated and the Tor network generally no longer supports V2 Onion
-	/// addresses.
-	OnionV2{
-		/// The base32 of first 80 bits
-		addr: [u8; 10],
-		/// The port on which the node is listening
-		port: u16,
-	},
+	/// addresses. Thus, the details are not parsed here.
+	OnionV2([u8; 12]),
 	/// A new-style Tor onion address/port on which the peer is listening.
 	///
 	/// To create the human-readable "hostname", concatenate the ED25519 pubkey, checksum, and version,
@@ -810,7 +805,7 @@ impl SocketAddress {
 		match self {
 			&SocketAddress::TcpIpV4 {..} => { 1 },
 			&SocketAddress::TcpIpV6 {..} => { 2 },
-			&SocketAddress::OnionV2 {..} => { 3 },
+			&SocketAddress::OnionV2(_) => { 3 },
 			&SocketAddress::OnionV3 {..} => { 4 },
 			&SocketAddress::Hostname {..} => { 5 },
 		}
@@ -821,7 +816,7 @@ impl SocketAddress {
 		match self {
 			&SocketAddress::TcpIpV4 { .. } => { 6 },
 			&SocketAddress::TcpIpV6 { .. } => { 18 },
-			&SocketAddress::OnionV2 { .. } => { 12 },
+			&SocketAddress::OnionV2(_) => { 12 },
 			&SocketAddress::OnionV3 { .. } => { 37 },
 			// Consists of 1-byte hostname length, hostname bytes, and 2-byte port.
 			&SocketAddress::Hostname { ref hostname, .. } => { u16::from(hostname.len()) + 3 },
@@ -847,10 +842,9 @@ impl Writeable for SocketAddress {
 				addr.write(writer)?;
 				port.write(writer)?;
 			},
-			&SocketAddress::OnionV2{ ref addr, ref port } => {
+			&SocketAddress::OnionV2(bytes) => {
 				3u8.write(writer)?;
-				addr.write(writer)?;
-				port.write(writer)?;
+				bytes.write(writer)?;
 			},
 			&SocketAddress::OnionV3 { ref ed25519_pubkey, ref checksum, ref version, ref port } => {
 				4u8.write(writer)?;
@@ -885,10 +879,7 @@ impl Readable for Result<SocketAddress, u8> {
 					port: Readable::read(reader)?,
 				}))
 			},
-			3 => Ok(Ok(SocketAddress::OnionV2 {
-				addr: Readable::read(reader)?,
-				port: Readable::read(reader)?,
-			})),
+			3 => Ok(Ok(SocketAddress::OnionV2(Readable::read(reader)?))),
 			4 => {
 				Ok(Ok(SocketAddress::OnionV3 {
 					ed25519_pubkey: Readable::read(reader)?,
@@ -967,23 +958,24 @@ impl From<std::net::SocketAddr> for SocketAddress {
 		}
 }
 
-/// Parses an Onion host and port into a [`SocketAddress::OnionV3`].
+/// Parses an Onion host and port into a [`SocketAddress::OnionV3`] or [`SocketAddress::OnionV2`].
 ///
 /// The host part must end with ".onion".
 pub fn parse_onion_address(host: &str, port: u16) -> Result<SocketAddress, SocketAddressParseError> {
 	if host.ends_with(".onion") {
 		let domain = &host[..host.len() - ".onion".len()];
-		if domain.len() != 56 && domain.len() !=16 {
-			return Err(SocketAddressParseError::InvalidOnion);
-		}
-		let onion = base32::Alphabet::RFC4648 { padding: false }.decode(&domain).map_err(|_| SocketAddressParseError::InvalidOnion)?;
-		if onion.len() != 35 && onion.len() != 10 {
+		if domain.len() != 56 && domain.len() != 16 {
 			return Err(SocketAddressParseError::InvalidOnion);
 		}
+		let mut onion = base32::Alphabet::RFC4648 { padding: false }.decode(&domain).map_err(|_| SocketAddressParseError::InvalidOnion)?;
 		if onion.len() == 10 {
-			let mut addr = [0; 10];
-			addr.copy_from_slice(&onion);
-			return Ok(SocketAddress::OnionV2{ addr, port });
+			onion.extend_from_slice(&port.to_be_bytes());
+			let mut bytes = [0; 12];
+			bytes.copy_from_slice(&onion);
+			return Ok(SocketAddress::OnionV2(bytes));
+		}
+		if onion.len() != 35 {
+			return Err(SocketAddressParseError::InvalidOnion);
 		}
 		let version = onion[0];
 		let first_checksum_flag = onion[1];
@@ -999,8 +991,9 @@ pub fn parse_onion_address(host: &str, port: u16) -> Result<SocketAddress, Socke
 }
 
 /// [`SocketAddress::OnionV2`] to onion address string
-pub fn to_onion_v2_string(addr: &[u8; 10], port: &u16) -> String {
-	let onion = base32::Alphabet::RFC4648 { padding: false }.encode(&addr[..]);
+pub fn to_onion_v2_string(bytes: &[u8; 12]) -> String {
+	let onion = base32::Alphabet::RFC4648 { padding: false }.encode(&bytes[..10]);
+	let port = u16::from_be_bytes([bytes[10], bytes[11]]);
 	format!("{}.onion:{}", onion, port)
 }
 
@@ -1019,7 +1012,7 @@ impl Display for SocketAddress {
 		match self {
 			SocketAddress::TcpIpV4{addr, port} => write!(f, "{}:{}", std::net::Ipv4Addr::from(*addr), port)?,
 			SocketAddress::TcpIpV6{addr, port} => write!(f, "[{}]:{}", std::net::Ipv6Addr::from(*addr), port)?,
-			SocketAddress::OnionV2{addr, port} => write!(f, "{}", to_onion_v2_string(addr, port))?,
+			SocketAddress::OnionV2(bytes) => write!(f, "{}", to_onion_v2_string(&bytes))?,
 			SocketAddress::OnionV3 {
 				ed25519_pubkey,
 				checksum,
@@ -2904,10 +2897,9 @@ mod tests {
 			});
 		}
 		if onionv2 {
-			addresses.push(msgs::SocketAddress::OnionV2 {
-				addr: [255, 254, 253, 252, 251, 250, 249, 248, 247, 246],
-				port: 9735,
-			});
+			addresses.push(msgs::SocketAddress::OnionV2(
+				[255, 254, 253, 252, 251, 250, 249, 248, 247, 246, 38, 7]
+			));
 		}
 		if onionv3 {
 			addresses.push(msgs::SocketAddress::OnionV3 {
@@ -4136,11 +4128,8 @@ mod tests {
 		assert_eq!(hostname, SocketAddress::from_str("lightning-node.mydomain.com:1234").unwrap());
 		assert_eq!(hostname, SocketAddress::from_str(&hostname.to_string()).unwrap());
 
-		let onion_v2 = SocketAddress::OnionV2{
-			addr: [40, 4, 64, 185, 202, 19, 162, 75, 90, 200],
-			port: 80,
-		};
-		assert_eq!(onion_v2, SocketAddress::from_str("facebookcorewwwi.onion:80").unwrap());
+		let onion_v2 = SocketAddress::OnionV2 ([40, 4, 64, 185, 202, 19, 162, 75, 90, 200, 38, 7],);
+		assert_eq!(onion_v2, SocketAddress::from_str("facebookcorewwwi.onion:9735").unwrap());
 		assert_eq!(onion_v2, SocketAddress::from_str(&onion_v2.to_string()).unwrap());
 
 		let onion_v3 = SocketAddress::OnionV3 {

lightning/src/util/ser.rs

@@ -587,7 +587,7 @@ macro_rules! impl_array {
 
 impl_array!(3, u8); // for rgb, ISO 4712 code
 impl_array!(4, u8); // for IPv4
-impl_array!(10, u8); // for OnionV2
+impl_array!(12, u8); // for OnionV2
 impl_array!(16, u8); // for IPv6
 impl_array!(32, u8); // for channel id & hmac
 impl_array!(PUBLIC_KEY_SIZE, u8); // for PublicKey