From 678e320a52fbcbfdc546d75610c2004239875541 Mon Sep 17 00:00:00 2001
From: Alan Lu <alanlu1023@gmail.com>
Date: Mon, 28 Dec 2020 14:12:50 -0600
Subject: [PATCH] Generalize proxy setup and move version-specific calldata
 into facade

---
 contracts/solc-0.8/CPKFactory.sol            | 28 ++++++++++++++------
 contracts/solc-0.8/CPKFactoryFacade.sol      | 24 +++++++++++++++--
 contracts/solc-0.8/dep-ports/IGnosisSafe.sol | 17 ------------
 3 files changed, 42 insertions(+), 27 deletions(-)
 delete mode 100644 contracts/solc-0.8/dep-ports/IGnosisSafe.sol

diff --git a/contracts/solc-0.8/CPKFactory.sol b/contracts/solc-0.8/CPKFactory.sol
index e4542f9e..63692bb6 100644
--- a/contracts/solc-0.8/CPKFactory.sol
+++ b/contracts/solc-0.8/CPKFactory.sol
@@ -1,7 +1,6 @@
 // SPDX-License-Identifier: GPL-3.0-only
 pragma solidity >=0.8.0;
 
-import { IGnosisSafe } from "./dep-ports/IGnosisSafe.sol";
 import { IGnosisSafeProxyFactory } from "./dep-ports/IGnosisSafeProxyFactory.sol";
 import { ProxyImplSetter } from "./ProxyImplSetter.sol";
 
@@ -39,8 +38,7 @@ contract CPKFactory {
         address owner,
         address safeVersion,
         uint256 salt,
-        address fallbackHandler,
-        bytes calldata execTxCalldata
+        bytes[] calldata txsCalldata
     )
         external
         payable
@@ -56,13 +54,27 @@ contract CPKFactory {
 
         ProxyImplSetter(proxy).setImplementation(safeVersion);
 
-        {
-            address[] memory tmp = new address[](1);
-            tmp[0] = address(owner);
-            IGnosisSafe(proxy).setup(tmp, 1, address(0), "", fallbackHandler, address(0), 0, payable(0));
+        bytes memory lastReturnData;
+
+        for (uint i = 0; i < txsCalldata.length; i++) {
+            bool txSuccess;
+            (txSuccess, lastReturnData) = proxy.call{value: msg.value}(txsCalldata[i]);
+            assembly {
+                // txSuccess == 0 means the call failed
+                if iszero(txSuccess) {
+                    // The revert data begins one word after the lastReturnData pointer.
+                    // At the location lastReturnData in memory, the length of the bytes is stored.
+                    // This differs from the high-level revert(string(lastReturnData))
+                    // as the high-level version encodes the lastReturnData in a Error(string) object.
+                    // We want to avoid that because the underlying call should have already
+                    // formatted the data in an Error(string) object
+                    revert(add(0x20, lastReturnData), mload(lastReturnData))
+                }
+            }
         }
 
-        proxy.call{value: msg.value}(execTxCalldata);
+        // final call in txsCalldata is assumed to be execTransaction
+        execTransactionSuccess = abi.decode(lastReturnData, (bool));
 
         emit CPKCreation(proxy, safeVersion, owner, salt);
     }
diff --git a/contracts/solc-0.8/CPKFactoryFacade.sol b/contracts/solc-0.8/CPKFactoryFacade.sol
index 6757647c..05ac59f1 100644
--- a/contracts/solc-0.8/CPKFactoryFacade.sol
+++ b/contracts/solc-0.8/CPKFactoryFacade.sol
@@ -56,12 +56,32 @@ contract CPKFactoryFacade {
             )
         }
 
+        bytes[] memory txsCalldata = new bytes[](2);
+        {
+            address[] memory owners = new address[](1);
+            owners[0] = address(owner);
+            txsCalldata[0] = abi.encodeWithSignature("setup("
+                "address[]," // owners
+                "uint256,"   // threshold
+                "address,"   // to
+                "bytes,"     // data
+                "address,"   // fallbackHandler
+                "address,"   // paymentToken
+                "uint256,"   // payment
+                "address"    // paymentReceiver
+            ")", owners, uint256(1), address(0), "", fallbackHandler, address(0), uint256(0), payable(0));
+        }
+
+        // msg.data works here as a substitute for encoding because this function's signature
+        // exactly matches the execTransaction signature from the Gnosis Safe, so the calldata
+        // encoding will be the same.
+        txsCalldata[1] = msg.data;
+
         return cpkFactory.createProxyAndExecTransaction{value: msg.value}(
             owner,
             safeVersion,
             salt,
-            fallbackHandler,
-            msg.data
+            txsCalldata
         );
     }
 }
\ No newline at end of file
diff --git a/contracts/solc-0.8/dep-ports/IGnosisSafe.sol b/contracts/solc-0.8/dep-ports/IGnosisSafe.sol
deleted file mode 100644
index 9b0896a5..00000000
--- a/contracts/solc-0.8/dep-ports/IGnosisSafe.sol
+++ /dev/null
@@ -1,17 +0,0 @@
-// SPDX-License-Identifier: GPL-3.0-only
-pragma solidity >=0.8.0;
-
-import { Enum } from "./Enum.sol";
-
-interface IGnosisSafe {
-    function setup(
-        address[] calldata _owners,
-        uint256 _threshold,
-        address to,
-        bytes calldata data,
-        address fallbackHandler,
-        address paymentToken,
-        uint256 payment,
-        address payable paymentReceiver
-    ) external;
-}