Use Hash160 for strongly typed arguments

src/contracts.rs

@@ -8,6 +8,7 @@ use bitcoin::{
         opcodes,
         script::{Builder, Instruction, Script},
     },
+    hashes::{hash160::Hash as Hash160, Hash},
     secp256k1,
     secp256k1::{Message, Secp256k1, SecretKey, Signature},
     util::bip143::SigHashCache,
@@ -78,7 +79,7 @@ pub fn derive_maker_pubkey_and_nonce(
 pub fn create_contract_redeemscript(
     pub_hashlock: &PublicKey,
     pub_timelock: &PublicKey,
-    hashvalue: [u8; 20],
+    hashvalue: Hash160,
     locktime: u16,
 ) -> Script {
     Builder::new()
@@ -105,8 +106,10 @@ pub fn create_contract_redeemscript(
 }
 
 //TODO put all these magic numbers in a const or something
-pub fn read_hashvalue_from_contract(redeemscript: &Script) -> Result<[u8; 20], TryFromSliceError> {
-    redeemscript.to_bytes()[4..24].try_into()
+pub fn read_hashvalue_from_contract(redeemscript: &Script) -> Result<Hash160, TryFromSliceError> {
+    Ok(Hash160::from_inner(
+        redeemscript.to_bytes()[4..24].try_into()?,
+    ))
 }
 
 pub fn read_locktime_from_contract(redeemscript: &Script) -> Option<u16> {
@@ -186,7 +189,7 @@ fn is_contract_out_valid(
     contract_output: &TxOut,
     hashlock_pubkey: &PublicKey,
     timelock_pubkey: &PublicKey,
-    hashvalue: [u8; 20],
+    hashvalue: Hash160,
     locktime: u16,
 ) -> Result<(), Error> {
     let minimum_locktime = 2; //TODO should be in config file or something
@@ -215,7 +218,7 @@ pub fn validate_and_sign_senders_contract_tx(
     senders_contract_tx: &Transaction,
     multisig_redeemscript: &Script,
     funding_input_value: u64,
-    hashvalue: [u8; 20],
+    hashvalue: Hash160,
     locktime: u16,
     tweakable_privkey: &SecretKey,
     wallet: &mut Wallet,
@@ -667,7 +670,7 @@ mod test {
     #[test]
     fn test_contract_script_generation() {
         // create a random hashvalue
-        let hashvalue = thread_rng().gen::<[u8; 20]>();
+        let hashvalue = Hash160::from_inner(thread_rng().gen::<[u8; 20]>());
 
         let pub_hashlock = PublicKey::from_str(
             "032e58afe51f9ed8ad3cc7897f634d881fdbe49a81564629ded8156bebd2ffd1af",
@@ -691,7 +694,7 @@ mod test {
 
         // Below is hand made script string that should be expected
         let expected = "827ca914".to_owned()
-            + &hashvalue.to_hex()[..]
+            + &hashvalue.as_inner().to_hex()[..]
             + "876321"
             + &pub_hashlock.to_string()[..]
             + "0120516721"

src/maker_protocol.rs

@@ -603,7 +603,7 @@ fn handle_hash_preimage(
     wallet: Arc<RwLock<Wallet>>,
     message: HashPreimage,
 ) -> Result<Option<MakerToTakerMessage>, Error> {
-    let hashvalue = Hash160::hash(&message.preimage).into_inner();
+    let hashvalue = Hash160::hash(&message.preimage);
     {
         let mut wallet_mref = wallet.write().unwrap();
         for multisig_redeemscript in message.senders_multisig_redeemscripts {

src/messages.rs

@@ -6,6 +6,7 @@
 
 use serde::{Deserialize, Serialize};
 
+use bitcoin::hashes::hash160::Hash as Hash160;
 use bitcoin::secp256k1::{SecretKey, Signature};
 use bitcoin::util::key::PublicKey;
 use bitcoin::{Script, Transaction};
@@ -37,7 +38,7 @@ pub struct SenderContractTxNoncesInfo {
 #[derive(Debug, Serialize, Deserialize)]
 pub struct SignSendersContractTx {
     pub txes_info: Vec<SenderContractTxNoncesInfo>,
-    pub hashvalue: [u8; 20],
+    pub hashvalue: Hash160,
     pub locktime: u16,
 }
 

src/taker_protocol.rs

@@ -70,7 +70,7 @@ async fn send_coinswap(
 
     let mut preimage = [0u8; 32];
     OsRng.fill_bytes(&mut preimage);
-    let hashvalue = Hash160::hash(&preimage).into_inner();
+    let hashvalue = Hash160::hash(&preimage);
 
     let first_swap_locktime = REFUND_LOCKTIME + REFUND_LOCKTIME_STEP * maker_count;
 
@@ -507,7 +507,7 @@ async fn request_senders_contract_tx_signatures<S: SwapCoin>(
     maker_multisig_nonces: &[SecretKey],
     maker_hashlock_nonces: &[SecretKey],
     timelock_pubkeys: &[PublicKey],
-    hashvalue: [u8; 20],
+    hashvalue: Hash160,
     locktime: u16,
 ) -> Result<Vec<Signature>, Error> {
     println!(
@@ -713,7 +713,7 @@ async fn send_proof_of_funding_and_get_contract_txes(
     next_peer_hashlock_pubkeys: &[PublicKey],
     maker_refund_locktime: u16,
     this_maker_contract_txes: &[Transaction],
-    hashvalue: [u8; 20],
+    hashvalue: Hash160,
 ) -> Result<(SignSendersAndReceiversContractTxes, Vec<Script>), Error> {
     send_message(
         socket_writer,

src/wallet_sync.rs

@@ -21,7 +21,10 @@ use bitcoin::{
         opcodes::all,
         script::{Builder, Script},
     },
-    hashes::hex::{FromHex, ToHex},
+    hashes::{
+        hash160::Hash as Hash160,
+        hex::{FromHex, ToHex},
+    },
     secp256k1,
     secp256k1::{Secp256k1, SecretKey, Signature},
     util::{
@@ -604,7 +607,7 @@ impl Wallet {
     pub fn find_incomplete_coinswaps(
         &self,
         rpc: &Client,
-    ) -> Result<HashMap<[u8; 20], Vec<(ListUnspentResultEntry, &WalletSwapCoin)>>, Error> {
+    ) -> Result<HashMap<Hash160, Vec<(ListUnspentResultEntry, &WalletSwapCoin)>>, Error> {
         rpc.call::<Value>("lockunspent", &[Value::Bool(true)])
             .map_err(|e| Error::Rpc(e))?;
 
@@ -613,11 +616,11 @@ impl Wallet {
             .values()
             .filter(|sc| sc.other_privkey.is_some())
             .map(|sc| read_hashvalue_from_contract(&sc.contract_redeemscript).unwrap())
-            .collect::<HashSet<[u8; 20]>>();
+            .collect::<HashSet<Hash160>>();
         //TODO make this read_hashvalue_from_contract() a struct function of WalletCoinSwap
 
         let mut incomplete_swapcoin_groups =
-            HashMap::<[u8; 20], Vec<(ListUnspentResultEntry, &WalletSwapCoin)>>::new();
+            HashMap::<Hash160, Vec<(ListUnspentResultEntry, &WalletSwapCoin)>>::new();
         for utxo in rpc.list_unspent(None, None, None, None, None)? {
             if utxo.descriptor.is_none() {
                 continue;
@@ -1054,7 +1057,7 @@ impl Wallet {
         total_coinswap_amount: u64,
         other_multisig_pubkeys: &[PublicKey],
         hashlock_pubkeys: &[PublicKey],
-        hashvalue: [u8; 20],
+        hashvalue: Hash160,
         locktime: u16, //returns: funding_txes, swapcoins, timelock_pubkeys
     ) -> Result<(Vec<Transaction>, Vec<WalletSwapCoin>, Vec<PublicKey>), Error> {
         let (coinswap_addresses, my_multisig_privkeys): (Vec<_>, Vec<_>) = other_multisig_pubkeys