Modify routing logic

With changes in this commit the vault shares will be held by the main
Acre contract.

core/contracts/Acre.sol

@@ -3,6 +3,7 @@ pragma solidity ^0.8.21;
 
 import "@openzeppelin/contracts/token/ERC20/extensions/ERC4626.sol";
 import "@openzeppelin/contracts/access/Ownable.sol";
+import {SafeERC20} from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
 
 import "./Dispatcher.sol";
 
@@ -18,6 +19,10 @@ import "./Dispatcher.sol";
 ///      burning of shares (stBTC), which are represented as standard ERC20
 ///      tokens, providing a seamless exchange with tBTC tokens.
 contract Acre is ERC4626, Ownable {
+    using SafeERC20 for IERC20;
+
+    error CallerNotDispatcher();
+
     event StakeReferral(bytes32 indexed referral, uint256 assets);
 
     Dispatcher public dispatcher;
@@ -53,10 +58,18 @@ contract Acre is ERC4626, Ownable {
     function upgradeDispatcher(Dispatcher _newDispatcher) public onlyOwner {
         if (address(dispatcher) != address(0)) {
             IERC20(asset()).approve(address(dispatcher), 0);
+            // TODO: Remove dispatcher's approvals for the vaults.
         }
 
         dispatcher = _newDispatcher;
 
         IERC20(asset()).approve(address(dispatcher), type(uint256).max);
     }
+
+    function approveVaultSharesForDispatcher(address vault, uint256 amount) external {
+        if (msg.sender != address(dispatcher)) revert CallerNotDispatcher();
+
+        // TODO: Emit event
+        IERC20(vault).safeIncreaseAllowance(address(dispatcher), amount);
+    }
 }

core/contracts/Dispatcher.sol

@@ -6,12 +6,14 @@ import "@openzeppelin/contracts/interfaces/IERC4626.sol";
 import {SafeERC20} from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
 
 import "./Router.sol";
+import "./Acre.sol";
 
 ///         a given vault and back. Vaults supply yield strategies with TBTC that
 ///         generate yield for Bitcoin holders.
-contract Dispatcher is Ownable {
+contract Dispatcher is Router, Ownable {
     using SafeERC20 for IERC20;
 
+
     error VaultAlreadyAuthorized();
     error VaultUnauthorized();
 
@@ -20,6 +22,7 @@ contract Dispatcher is Ownable {
     }
 
     Acre acre;
+    IERC20 tbtc;
 
     /// @notice Authorized Yield Vaults that implement ERC4626 standard. These
     ///         vaults deposit assets to yield strategies, e.g. Uniswap V3
@@ -33,8 +36,9 @@ contract Dispatcher is Ownable {
     event VaultAuthorized(address indexed vault);
     event VaultDeauthorized(address indexed vault);
 
-    constructor(Acre _acre) Ownable(msg.sender) {
+    constructor(Acre _acre, IERC20 _tbtc) Ownable(msg.sender) {
         acre = _acre;
+        tbtc = _tbtc;
     }
 
     /// @notice Adds a vault to the list of authorized vaults.
@@ -47,13 +51,15 @@ contract Dispatcher is Ownable {
         vaults.push(vault);
         vaultsInfo[vault].authorized = true;
 
+        acre.approveVaultSharesForDispatcher(vault, type(uint256).max);
+
         emit VaultAuthorized(vault);
     }
 
     /// @notice Removes a vault from the list of authorized vaults.
     /// @param vault Address of the vault to remove.
     function deauthorizeVault(address vault) external onlyOwner {
-        if (!vaultsInfo[vault].authorized) {
+        if (!isVaultAuthorized(vault)) {
             revert VaultUnauthorized();
         }
 
@@ -68,26 +74,63 @@ contract Dispatcher is Ownable {
             }
         }
 
+        acre.approveVaultSharesForDispatcher(vault, 0);
+
         emit VaultDeauthorized(vault);
     }
 
+    function isVaultAuthorized(address vault) public view returns (bool){
+        return vaultsInfo[vault].authorized;
+    }
+
     function getVaults() external view returns (address[] memory) {
         return vaults;
     }
 
-        return address(acre);
+
+// TODO: Add access restriction
+    function depositToVault(
+        IERC4626 vault,
+        uint256 amount,
+        uint256 minSharesOut
+    ) public returns (uint256 sharesOut) {
+        if (!isVaultAuthorized(address(vault))) {
+            revert VaultUnauthorized();
+        }
+
+        require(vault.asset() == address(tbtc), "vault asset is not tbtc");
+
+        IERC20(tbtc).safeTransferFrom(address(acre), address(this), amount);
+        IERC20(tbtc).approve(address(vault), amount);
+
+        Router.deposit(vault, address(acre), amount, minSharesOut);
     }
 
-    function sharesHolder() public virtual override returns (address){
-        return address(this);
+// TODO: Add access restriction
+    function withdrawFromVault(
+        IERC4626 vault,
+        uint256 amount,
+        uint256 maxSharesOut
+    ) public returns (uint256 sharesOut) {
+        uint256 shares = vault.previewWithdraw(amount);
+
+        IERC20(vault).safeTransferFrom(address(acre), address(this), shares);
+        IERC20(vault).approve(address(vault), shares);
+
+        Router.withdraw(vault, address(acre), amount, maxSharesOut);
     }
 
-    function migrateShares(IERC4626[] calldata _vaults) public onlyOwner {
-        address newDispatcher = address(acre.dispatcher());
+// TODO: Add access restriction
+    function redeemFromVault(
+        IERC4626 vault,
+        uint256 shares,
+        uint256 minAmountOut
+    ) public returns (uint256 amountOut) {
+        IERC20(vault).safeTransferFrom(address(acre), address(this), shares);
+        IERC20(vault).approve(address(vault), shares);
 
-        require(newDispatcher != address(0), "new dispatcher address cannot be zero address");
+        Router.redeem(vault, address(acre), shares, minAmountOut);
+    }
 
-        for (uint i=0; i<_vaults.length; i++) {
-            _vaults[i].transfer(newDispatcher, _vaults[i].balanceOf(address(this)));
-        }
+    // TODO: Add function to withdrawMax
 }

core/contracts/Router.sol

@@ -2,15 +2,13 @@
 pragma solidity ^0.8.21;
 
 import "@openzeppelin/contracts/interfaces/IERC20.sol";
-import "@openzeppelin/contracts/interfaces/IERC4626.sol";
+import {IERC4626} from "@openzeppelin/contracts/interfaces/IERC4626.sol";
 import {SafeERC20} from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
-import "./Acre.sol";
 
 
 // TODO: Consider deploying ERC4626RouterBase from the ERC4626 Alliance.
 // TODO: Think about adding reentrancy guard
 // TODO: Add ACL
-
 abstract contract Router {
     using SafeERC20 for IERC20;
 
@@ -26,41 +24,46 @@ abstract contract Router {
     /// @notice thrown when amount of shares received is above the max set by caller
     error MaxSharesError();
 
-
-    function assetsHolder() public virtual returns (address);
-    function sharesHolder() public virtual returns (address);
-
+    // Copied from ERC4626RouterBase
+    // Differences:
+    // - internal instead of public
     function deposit(
         IERC4626 vault,
+        address to,
         uint256 amount,
         uint256 minSharesOut
-    ) public returns (uint256 sharesOut) {
-        IERC20(vault.asset()).safeTransferFrom(assetsHolder(), address(this), amount);
-
-        IERC20(vault.asset()).approve(address(vault), amount);
-
-        if ((sharesOut = vault.deposit(amount, sharesHolder())) < minSharesOut) {
+    ) internal virtual returns (uint256 sharesOut) {
+        if ((sharesOut = vault.deposit(amount, to)) < minSharesOut) {
             revert MinSharesError();
         }
     }
 
-
+    // Copied from ERC4626RouterBase
+    // Difference:
+    // - internal instead of public
+    // - use address(this) as owner instead of msg.sender
     function withdraw(
         IERC4626 vault,
+        address to,
         uint256 amount,
         uint256 maxSharesOut
-    ) public returns (uint256 sharesOut) {
-        if ((sharesOut = vault.withdraw(amount, assetsHolder(), sharesHolder())) > maxSharesOut) {
+    ) internal virtual returns (uint256 sharesOut) {
+        if ((sharesOut = vault.withdraw(amount, to, address(this))) > maxSharesOut) {
             revert MaxSharesError();
         }
     }
 
+    // Copied from ERC4626RouterBase
+    // Difference:
+    // - internal instead of public
+    // - use address(this) as owner instead of msg.sender
     function redeem(
         IERC4626 vault,
+        address to,
         uint256 shares,
         uint256 minAmountOut
-    ) public returns (uint256 amountOut) {
-        if ((amountOut = vault.redeem(shares, assetsHolder(), sharesHolder())) < minAmountOut) {
+    ) internal virtual returns (uint256 amountOut) {
+          if ((amountOut = vault.redeem(shares, to, address(this))) < minAmountOut) {
             revert MinAmountError();
         }
     }

core/deploy/02_deploy_dispatcher.ts

@@ -6,19 +6,30 @@ const func: DeployFunction = async (hre: HardhatRuntimeEnvironment) => {
   const { deployer } = await getNamedAccounts()
 
   const acre = await deployments.get("Acre")
+  // const router = await deployments.get("Router")
+  const tbtc = await deployments.get("TBTC")
 
   await deployments.deploy("Dispatcher", {
     from: deployer,
-    args: [acre.address],
+    args: [acre.address, tbtc.address],
     log: true,
     waitConfirmations: 1,
   })
 
+  const dispatcher = await deployments.get("Dispatcher")
+
+  await deployments.execute(
+    "Acre",
+    { from: deployer, log: true, waitConfirmations: 1 },
+    "upgradeDispatcher",
+    dispatcher.address,
+  )
+
   // TODO: Add Etherscan verification
   // TODO: Add Tenderly verification
 }
 
 export default func
 
 func.tags = ["Dispatcher"]
-func.dependencies = ["Acre"]
+func.dependencies = ["Acre", "TBTC"]

core/deploy/22_transfer_ownership_dispatcher.ts

@@ -19,3 +19,4 @@ const func: DeployFunction = async (hre: HardhatRuntimeEnvironment) => {
 export default func
 
 func.tags = ["TransferOwnershipDispatcher"]
+func.dependencies = ["Dispatcher"]