Add createAndSignBitcoinTx precompile (#3)

* forge install: openzeppelin-contracts

v5.0.2

* add UTXO manager contract

* rm utxo manager

* rm oz dep

* fmt

Author: PowVT

foundry.toml

@@ -16,4 +16,4 @@ remappings_generated = true
 remappings_regenerate = true
 
 # whether to suffix the remapping with the version: `name-a.b.c`
-remappings_version = false
+remappings_version = false

remappings.txt

@@ -1 +1 @@
-@solady=dependencies/solady-0.0.234/src
+@solady=dependencies/solady-0.0.234/src

soldeer.lock

@@ -1,6 +1,6 @@
-
 [[dependencies]]
 name = "solady"
 version = "0.0.234"
 source = "https://soldeer-revisions.s3.amazonaws.com/solady/0_0_234_19-08-2024_05:13:28_solady.zip"
 checksum = "a33f6d46a65c6a1adebed83365c128eab4c3e9d124b68fe5dea1a675a7f661a8"
+integrity = "afedc5ab760d5e83fcb7d4181fdb77fa2d829e6aca88653536c258fbd8656cdc"

src/GetBlock.sol

@@ -4,12 +4,11 @@ pragma solidity 0.8.26;
 library CorsaBitcoin {
     address private constant BTC_PRECOMPILE = address(0x999);
 
-    bytes4 private constant BROADCAST_LEADING_BYTE = 0x00000000;
-    bytes4 private constant GET_BLOCK_HEIGHT_LEADING_BYTE = 0x00000001;
-    bytes4 private constant DECODE_LEADING_BYTE = 0x00000002;
-    bytes4 private constant CHECKSIG_LEADING_BYTE = 0x00000003;
-    bytes4 private constant ADDRESS_CONVERT_LEADING_BYTE = 0x00000004;
-    bytes4 private constant SEND_BTC_LEADING_BYTE = 0x00000005;
+    bytes4 private constant BROADCAST_LEADING_BYTES = 0x00000001;
+    bytes4 private constant DECODE_LEADING_BYTES = 0x00000002;
+    bytes4 private constant CHECKSIG_LEADING_BYTES = 0x00000003;
+    bytes4 private constant ADDRESS_CONVERT_LEADING_BYTES = 0x00000004;
+    bytes4 private constant CREATE_AND_SIGN_LEADING_BYTES = 0x00000005;
 
     struct Output {
         string addr;
@@ -33,39 +32,50 @@ library CorsaBitcoin {
 
     error PrecompileCallFailed();
 
-    function decodeBitcoinTx(bytes calldata signedTx) internal view returns (BitcoinTx memory) {
+    function decodeBitcoinTx(bytes memory signedTx) internal view returns (BitcoinTx memory) {
         (bool success, bytes memory returndata) =
-            BTC_PRECOMPILE.staticcall(abi.encodePacked(DECODE_LEADING_BYTE, signedTx));
+            BTC_PRECOMPILE.staticcall(abi.encodePacked(DECODE_LEADING_BYTES, signedTx));
         if (!success) revert PrecompileCallFailed();
         return abi.decode(returndata, (BitcoinTx));
     }
 
     function checkSignature(bytes calldata signedTx) internal view returns (bool) {
-        (bool success,) = BTC_PRECOMPILE.staticcall(abi.encodePacked(CHECKSIG_LEADING_BYTE, signedTx));
+        (bool success,) = BTC_PRECOMPILE.staticcall(abi.encodePacked(CHECKSIG_LEADING_BYTES, signedTx));
         return success;
     }
 
     function convertEthToBtcAddress(address ethAddress) internal returns (bytes memory) {
         (bool success, bytes memory returndata) =
-            BTC_PRECOMPILE.call(abi.encodePacked(ADDRESS_CONVERT_LEADING_BYTE, ethAddress));
+            BTC_PRECOMPILE.call(abi.encodePacked(ADDRESS_CONVERT_LEADING_BYTES, ethAddress));
         if (!success) revert PrecompileCallFailed();
         return returndata;
     }
 
-    function broadcastBitcoinTx(bytes calldata signedTx) internal returns (bool) {
-        (bool success,) = BTC_PRECOMPILE.call(abi.encodePacked(BROADCAST_LEADING_BYTE, signedTx));
-        return success;
-    }
+    function broadcastBitcoinTx(bytes memory signedTx) internal returns (bytes32) {
+        (bool success, bytes memory returndata) =
+            BTC_PRECOMPILE.call(abi.encodePacked(BROADCAST_LEADING_BYTES, signedTx));
+        if (!success) revert PrecompileCallFailed();
 
-    function sendBitcoin(address from, uint256 amount, string calldata destination) internal returns (bool) {
-        (bool success,) = BTC_PRECOMPILE.call(abi.encodePacked(SEND_BTC_LEADING_BYTE, from, amount, destination));
-        return success;
+        require(returndata.length == 32, "Invalid txid length");
+
+        bytes32 txid;
+        assembly {
+            txid := mload(add(returndata, 32))
+        }
+
+        return txid;
     }
 
-    function getCurrentBlockHeight() internal view returns (uint256) {
-        (bool success, bytes memory returndata) =
-            BTC_PRECOMPILE.staticcall(abi.encodePacked(GET_BLOCK_HEIGHT_LEADING_BYTE));
+    function createAndSignBitcoinTx(address signer, uint64 amount, uint64 blockHeight, string memory destinationAddress)
+        internal
+        returns (bytes memory)
+    {
+        bytes memory inputData =
+            abi.encode(CREATE_AND_SIGN_LEADING_BYTES, signer, amount, blockHeight, destinationAddress);
+
+        (bool success, bytes memory returndata) = BTC_PRECOMPILE.call(inputData);
         if (!success) revert PrecompileCallFailed();
-        return abi.decode(returndata, (uint256));
+
+        return returndata;
     }
 }

src/lib/CorsaBitcoin.sol

@@ -13,6 +13,10 @@ contract uBTC is WETH, Ownable {
     error UnsignedInput();
     error InvalidLocktime();
     error BroadcastFailure();
+    error AmountTooBig();
+
+    event Deposit(bytes32 txid, uint256 amount);
+    event Withdraw(bytes32 txid, uint256 amount);
 
     constructor() WETH() Ownable() {
         _initializeOwner(msg.sender);
@@ -43,6 +47,10 @@ contract uBTC is WETH, Ownable {
         CorsaBitcoin.BitcoinTx memory btcTx = CorsaBitcoin.decodeBitcoinTx(signedTx);
 
         // input validations
+        if (amount >= type(uint64).max) {
+            revert AmountTooBig();
+        }
+
         if (btcTx.outputs.length < 1 || btcTx.outputs[0].value < amount) {
             revert InsufficientDeposit();
         }
@@ -72,19 +80,23 @@ contract uBTC is WETH, Ownable {
         _mint(msg.sender, amount);
 
         // Broadcast signed btc tx
-        if (!CorsaBitcoin.broadcastBitcoinTx(signedTx)) {
-            revert BroadcastFailure();
-        }
+        bytes32 txid = CorsaBitcoin.broadcastBitcoinTx(signedTx);
+
+        emit Deposit(txid, amount);
     }
 
-    function withdraw(uint256 amount, string calldata dest) public {
+    function withdraw(uint64 amount, uint32 btcBlockHeight, string calldata dest) public {
         // burn uBTC
-        _burn(msg.sender, amount);
+        // TODO(powvt): how to account for gas fees? burn and have user pay?
+        _burn(msg.sender, uint256(amount));
 
-        // sign BTC tx for sending amount to specified destination, then broadcast tx
-        if (!CorsaBitcoin.sendBitcoin(address(this), amount, dest)) {
-            revert BroadcastFailure();
-        }
+        // Create Bitcoin transaction using the UTXOs
+        bytes memory signedTx = CorsaBitcoin.createAndSignBitcoinTx(address(this), amount, btcBlockHeight, dest);
+
+        // Broadcast signed BTC tx
+        bytes32 txid = CorsaBitcoin.broadcastBitcoinTx(signedTx);
+
+        emit Withdraw(txid, amount);
     }
 
     function adminBurn(address wallet, uint256 amount) public onlyOwner {