X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;ds=sidebyside;f=src%2Fln%2Fmsgs.rs;fp=src%2Fln%2Fmsgs.rs;h=494abf1953616f8dd46f720d40dc735f4d31dfe2;hb=70d06b46106a49d1434ac168175859278db92620;hp=4cff6256f83f9176460d80f23044d93036114b7a;hpb=301f91e2a2878c0e43763fa689f68b2b1fddb9c9;p=rust-lightning

diff --git a/src/ln/msgs.rs b/src/ln/msgs.rs
index 4cff6256..494abf19 100644
--- a/src/ln/msgs.rs
+++ b/src/ln/msgs.rs
@@ -191,7 +191,7 @@ pub struct OpenChannel {
 	pub(crate) htlc_basepoint: PublicKey,
 	pub(crate) first_per_commitment_point: PublicKey,
 	pub(crate) channel_flags: u8,
-	pub(crate) shutdown_scriptpubkey: Option<Script>,
+	pub(crate) shutdown_scriptpubkey: OptionalField<Script>,
 }
 
 /// An accept_channel message to be sent or received from a peer
@@ -211,7 +211,7 @@ pub struct AcceptChannel {
 	pub(crate) delayed_payment_basepoint: PublicKey,
 	pub(crate) htlc_basepoint: PublicKey,
 	pub(crate) first_per_commitment_point: PublicKey,
-	pub(crate) shutdown_scriptpubkey: Option<Script>,
+	pub(crate) shutdown_scriptpubkey: OptionalField<Script>
 }
 
 /// A funding_created message to be sent or received from a peer
@@ -323,7 +323,7 @@ pub struct ChannelReestablish {
 	pub(crate) channel_id: [u8; 32],
 	pub(crate) next_local_commitment_number: u64,
 	pub(crate) next_remote_commitment_number: u64,
-	pub(crate) data_loss_protect: Option<DataLossProtect>,
+	pub(crate) data_loss_protect: OptionalField<DataLossProtect>,
 }
 
 /// An announcement_signatures message to be sent or received from a peer
@@ -518,6 +518,18 @@ pub enum HTLCFailChannelUpdate {
 	}
 }
 
+/// Messages could have optional fields to use with extended features
+/// As we wish to serialize these differently from Option<T>s (Options get a tag byte, but
+/// OptionalFeild simply gets Present if there are enough bytes to read into it), we have a
+/// separate enum type for them.
+#[derive(Clone, PartialEq)]
+pub enum OptionalField<T> {
+	/// Optional field is included in message
+	Present(T),
+	/// Optional field is absent in message
+	Absent
+}
+
 /// A trait to describe an object which can receive channel messages.
 ///
 /// Messages MAY be called in parallel when they originate from different their_node_ids, however
@@ -696,8 +708,35 @@ impl From<::std::io::Error> for DecodeError {
 	}
 }
 
+impl Writeable for OptionalField<Script> {
+	fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
+		match *self {
+			OptionalField::Present(ref script) => {
+				// Note that Writeable for script includes the 16-bit length tag for us
+				script.write(w)?;
+			},
+			OptionalField::Absent => {}
+		}
+		Ok(())
+	}
+}
+
+impl<R: Read> Readable<R> for OptionalField<Script> {
+	fn read(r: &mut R) -> Result<Self, DecodeError> {
+		match <u16 as Readable<R>>::read(r) {
+			Ok(len) => {
+				let mut buf = vec![0; len as usize];
+				r.read_exact(&mut buf)?;
+				Ok(OptionalField::Present(Script::from(buf)))
+			},
+			Err(DecodeError::ShortRead) => Ok(OptionalField::Absent),
+			Err(e) => Err(e)
+		}
+	}
+}
+
 impl_writeable_len_match!(AcceptChannel, {
-		{AcceptChannel{ shutdown_scriptpubkey: Some(ref script), ..}, 270 + 2 + script.len()},
+		{AcceptChannel{ shutdown_scriptpubkey: OptionalField::Present(ref script), .. }, 270 + 2 + script.len()},
 		{_, 270}
 	}, {
 	temporary_channel_id,
@@ -726,13 +765,16 @@ impl_writeable!(AnnouncementSignatures, 32+8+64*2, {
 
 impl Writeable for ChannelReestablish {
 	fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
-		w.size_hint(if self.data_loss_protect.is_some() { 32+2*8+33+32 } else { 32+2*8 });
+		w.size_hint(if let OptionalField::Present(..) = self.data_loss_protect { 32+2*8+33+32 } else { 32+2*8 });
 		self.channel_id.write(w)?;
 		self.next_local_commitment_number.write(w)?;
 		self.next_remote_commitment_number.write(w)?;
-		if let Some(ref data_loss_protect) = self.data_loss_protect {
-			data_loss_protect.your_last_per_commitment_secret.write(w)?;
-			data_loss_protect.my_current_per_commitment_point.write(w)?;
+		match self.data_loss_protect {
+			OptionalField::Present(ref data_loss_protect) => {
+				(*data_loss_protect).your_last_per_commitment_secret.write(w)?;
+				(*data_loss_protect).my_current_per_commitment_point.write(w)?;
+			},
+			OptionalField::Absent => {}
 		}
 		Ok(())
 	}
@@ -747,11 +789,11 @@ impl<R: Read> Readable<R> for ChannelReestablish{
 			data_loss_protect: {
 				match <[u8; 32] as Readable<R>>::read(r) {
 					Ok(your_last_per_commitment_secret) =>
-						Some(DataLossProtect {
+						OptionalField::Present(DataLossProtect {
 							your_last_per_commitment_secret,
 							my_current_per_commitment_point: Readable::read(r)?,
 						}),
-					Err(DecodeError::ShortRead) => None,
+					Err(DecodeError::ShortRead) => OptionalField::Absent,
 					Err(e) => return Err(e)
 				}
 			}
@@ -818,8 +860,8 @@ impl_writeable_len_match!(Init, {
 });
 
 impl_writeable_len_match!(OpenChannel, {
-		{ OpenChannel { shutdown_scriptpubkey: Some(ref script), .. }, 319 + 2 + script.len() },
-		{ OpenChannel { shutdown_scriptpubkey: None, .. }, 319 }
+		{ OpenChannel { shutdown_scriptpubkey: OptionalField::Present(ref script), .. }, 319 + 2 + script.len() },
+		{ _, 319 }
 	}, {
 	chain_hash,
 	temporary_channel_id,
@@ -1322,6 +1364,7 @@ impl_writeable_len_match!(NodeAnnouncement, {
 mod tests {
 	use hex;
 	use ln::msgs;
+	use ln::msgs::OptionalField;
 	use util::ser::Writeable;
 	use secp256k1::key::{PublicKey,SecretKey};
 	use secp256k1::Secp256k1;
@@ -1332,7 +1375,7 @@ mod tests {
 			channel_id: [4, 0, 0, 0, 0, 0, 0, 0, 5, 0, 0, 0, 0, 0, 0, 0, 6, 0, 0, 0, 0, 0, 0, 0, 7, 0, 0, 0, 0, 0, 0, 0],
 			next_local_commitment_number: 3,
 			next_remote_commitment_number: 4,
-			data_loss_protect: None,
+			data_loss_protect: OptionalField::Absent,
 		};
 
 		let encoded_value = cr.encode();
@@ -1353,7 +1396,7 @@ mod tests {
 			channel_id: [4, 0, 0, 0, 0, 0, 0, 0, 5, 0, 0, 0, 0, 0, 0, 0, 6, 0, 0, 0, 0, 0, 0, 0, 7, 0, 0, 0, 0, 0, 0, 0],
 			next_local_commitment_number: 3,
 			next_remote_commitment_number: 4,
-			data_loss_protect: Some(msgs::DataLossProtect { your_last_per_commitment_secret: [9;32], my_current_per_commitment_point: public_key}),
+			data_loss_protect: OptionalField::Present(msgs::DataLossProtect { your_last_per_commitment_secret: [9;32], my_current_per_commitment_point: public_key}),
 		};
 
 		let encoded_value = cr.encode();