Migrate all Uint256s used for channel_ids to [u8; 32]

[rust-lightning] / src / chain / transaction.rs

diff --git a/src/chain/transaction.rs b/src/chain/transaction.rs
index 42a4f952e4150550f240c9c59d5d89a9a885c7de..934c772727862c2ebca1b1e73521cdd4fdfadb4b 100644 (file)
--- a/src/chain/transaction.rs
+++ b/src/chain/transaction.rs
@@ -1,5 +1,4 @@
 use bitcoin::util::hash::Sha256dHash;
-use bitcoin::util::uint::Uint256;
 
 /// A reference to a transaction output.
 /// Differs from bitcoin::blockdata::transaction::TxOutRef as the index is a u16 instead of usize
@@ -19,10 +18,33 @@ impl OutPoint {
        }
 
        /// Convert an `OutPoint` to a lightning channel id.
-       pub fn to_channel_id(&self) -> Uint256 {
-               let mut index = [0; 32];
-               index[30] = ((self.index >> 8) & 0xff) as u8;
-               index[31] = ((self.index >> 0) & 0xff) as u8;
-               self.txid.into_le() ^ Sha256dHash::from(&index[..]).into_le()
+       pub fn to_channel_id(&self) -> [u8; 32] {
+               let mut res = [0; 32];
+               res[..].copy_from_slice(&self.txid[..]);
+               res[30] ^= ((self.index >> 8) & 0xff) as u8;
+               res[31] ^= ((self.index >> 0) & 0xff) as u8;
+               res
+       }
+}
+
+#[cfg(test)]
+mod tests {
+       use chain::transaction::OutPoint;
+
+       use bitcoin::blockdata::transaction::Transaction;
+       use bitcoin::network::serialize;
+       use bitcoin::util::misc::hex_bytes;
+
+       #[test]
+       fn test_channel_id_calculation() {
+               let tx: Transaction = serialize::deserialize(&hex_bytes("020000000001010e0adef48412e4361325ac1c6e36411299ab09d4f083b9d8ddb55fbc06e1b0c00000000000feffffff0220a1070000000000220020f81d95e040bd0a493e38bae27bff52fe2bb58b93b293eb579c01c31b05c5af1dc072cfee54a3000016001434b1d6211af5551905dc2642d05f5b04d25a8fe80247304402207f570e3f0de50546aad25a872e3df059d277e776dda4269fa0d2cc8c2ee6ec9a022054e7fae5ca94d47534c86705857c24ceea3ad51c69dd6051c5850304880fc43a012103cb11a1bacc223d98d91f1946c6752e358a5eb1a1c983b3e6fb15378f453b76bd00000000").unwrap()[..]).unwrap();
+               assert_eq!(&OutPoint {
+                       txid: tx.txid(),
+                       index: 0
+               }.to_channel_id(), &hex_bytes("3e88dd7165faf7be58b3c5bb2c9c452aebef682807ea57080f62e6f6e113c25e").unwrap()[..]);
+               assert_eq!(&OutPoint {
+                       txid: tx.txid(),
+                       index: 1
+               }.to_channel_id(), &hex_bytes("3e88dd7165faf7be58b3c5bb2c9c452aebef682807ea57080f62e6f6e113c25f").unwrap()[..]);
        }
 }