llvm-context: disable call re-entrancy for send and transfer (#196)

CHANGELOG.md

@@ -15,6 +15,8 @@ Supported `polkadot-sdk` rev: `274a781e8ca1a9432c7ec87593bd93214abbff50`
 - Removed support for legacy EVM assembly (EVMLA) translation.
 - integration: identify cached code blobs on source code to fix potential confusions.
 - Setting base, include or allow paths in emscripten is now a hard error.
+- Employ a heuristic to detect `address.transfer` and `address.send` calls.
+  If detected, the re-entrant call flag is not set and 0 deposit limit is endowed.
 
 ### Fixed
 - Solidity: Add the solc `--libraries` files to sources.

crates/integration/contracts/Balance.sol

@@ -0,0 +1,81 @@
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8;
+
+/* runner.json
+{
+    "differential": true,
+    "actions": [
+        {
+            "Upload": {
+                "code": {
+                    "Solidity": {
+                        "contract": "BalanceReceiver"
+                    }
+                }
+            }
+        },
+        {
+            "Instantiate": {
+                "code": {
+                    "Solidity": {
+                        "contract": "Balance"
+                    }
+                },
+                "value": 24
+            }
+        },
+        {
+            "Call": {
+                "dest": {
+                    "Instantiated": 0
+                },
+                "data": "1c8d16b30000000000000000000000000303030303030303030303030303030303030303000000000000000000000000000000000000000000000000000000000000000a"
+            }
+        },
+        {
+            "Call": {
+                "dest": {
+                    "Instantiated": 0
+                },
+                "data": "6ada15d90000000000000000000000000303030303030303030303030303030303030303000000000000000000000000000000000000000000000000000000000000000a"
+            }
+        }
+    ]
+}
+*/
+
+contract BalanceReceiver {
+    constructor() payable {}
+
+    fallback() external payable {}
+}
+
+contract Balance {
+    constructor() payable {
+        // 0 to EOA
+        transfer_to(payable(address(0xdeadbeef)), 0);
+        send_to(payable(address(0xdeadbeef)), 0);
+
+        // 1 to EOA
+        transfer_to(payable(address(0xcafebabe)), 1);
+        send_to(payable(address(0xcafebabe)), 1);
+
+        BalanceReceiver balanceReceiver = new BalanceReceiver();
+
+        // 0 to contract
+        transfer_to(payable(address(balanceReceiver)), 0);
+        send_to(payable(address(balanceReceiver)), 0);
+
+        // 1 to contract
+        transfer_to(payable(address(balanceReceiver)), 1);
+        send_to(payable(address(balanceReceiver)), 1);
+    }
+
+    function transfer_to(address payable _dest, uint _amount) public payable {
+        _dest.transfer(_amount);
+    }
+
+    function send_to(address payable _dest, uint _amount) public payable {
+        require(_dest.send(_amount));
+    }
+}

crates/integration/contracts/Send.sol

@@ -0,0 +1,75 @@
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8;
+
+/* runner.json
+{
+    "differential": false,
+    "actions": [
+        {
+            "Instantiate": {
+                "code": {
+                    "Solidity": {
+                        "contract": "Send"
+                    }
+                },
+                "value": 211
+            }
+        },
+        {
+            "Call": {
+                "dest": {
+                    "Instantiated": 0
+                },
+                "data": "1c8d16b30000000000000000000000000303030303030303030303030303030303030303000000000000000000000000000000000000000000000000000000000000000a"
+            }
+        },
+        {
+            "VerifyCall": {
+                "success": true
+            }
+        },
+        {
+            "Call": {
+                "dest": {
+                    "Instantiated": 0
+                },
+                "data": "fb9e8d050000000000000000000000000000000000000000000000000000000000000001"
+            }
+        },
+        {
+            "VerifyCall": {
+                "success": false
+            }
+        },
+        {
+            "Call": {
+                "dest": {
+                    "Instantiated": 0
+                },
+                "data": "fb9e8d050000000000000000000000000000000000000000000000000000000000000000"
+            }
+        },
+        {
+            "VerifyCall": {
+                "success": false
+            }
+        }
+    ]
+}
+*/
+
+contract Send {
+    constructor() payable {}
+
+    function transfer_self(uint _amount) public payable {
+        transfer_to(payable(address(this)), _amount);
+    }
+
+    function transfer_to(address payable _dest, uint _amount) public payable {
+        if (_dest.send(_amount)) {}
+    }
+
+    fallback() external {}
+
+    receive() external payable {}
+}

crates/integration/contracts/Transfer.sol

@@ -3,7 +3,7 @@ pragma solidity ^0.8;
 
 /* runner.json
 {
-    "differential": true,
+    "differential": false,
     "actions": [
         {
             "Instantiate": {
@@ -12,7 +12,7 @@ pragma solidity ^0.8;
                         "contract": "Transfer"
                     }
                 },
-                "value": 11
+                "value": 211
             }
         },
         {
@@ -23,32 +23,53 @@ pragma solidity ^0.8;
                 "data": "1c8d16b30000000000000000000000000303030303030303030303030303030303030303000000000000000000000000000000000000000000000000000000000000000a"
             }
         },
+        {
+            "VerifyCall": {
+                "success": true
+            }
+        },
         {
             "Call": {
                 "dest": {
                     "Instantiated": 0
                 },
-                "data": "fb9e8d0500000000000000000000000003030303030303030303030303030303030303030000000000000000000000000000000000000000000000000000000000000001"
+                "data": "fb9e8d050000000000000000000000000000000000000000000000000000000000000001"
+            }
+        },
+        {
+            "VerifyCall": {
+                "success": false
+            }
+        },
+        {
+            "Call": {
+                "dest": {
+                    "Instantiated": 0
+                },
+                "data": "fb9e8d050000000000000000000000000000000000000000000000000000000000000000"
+            }
+        },
+        {
+            "VerifyCall": {
+                "success": false
             }
         }
     ]
 }
 */
 
 contract Transfer {
-    constructor() payable {
-        transfer_self(msg.value);
-    }
-
-    function address_self() internal view returns (address payable) {
-        return payable(address(this));
-    }
+    constructor() payable {}
 
     function transfer_self(uint _amount) public payable {
-        transfer_to(address_self(), _amount);
+        transfer_to(payable(address(this)), _amount);
     }
 
     function transfer_to(address payable _dest, uint _amount) public payable {
         _dest.transfer(_amount);
     }
+
+    fallback() external {}
+
+    receive() external payable {}
 }

crates/integration/src/cases.rs

@@ -156,6 +156,20 @@ case!("DivisionArithmetics.sol", DivisionArithmetics, sdivCall, division_arithme
 case!("DivisionArithmetics.sol", DivisionArithmetics, modCall, division_arithmetics_mod, n: U256, d: U256);
 case!("DivisionArithmetics.sol", DivisionArithmetics, smodCall, division_arithmetics_smod, n: I256, d: I256);
 
+sol!(
+    contract Send {
+        function transfer_self(uint _amount) public payable;
+    }
+);
+case!("Send.sol", Send, transfer_selfCall, send_self, amount: U256);
+
+sol!(
+    contract Transfer {
+        function transfer_self(uint _amount) public payable;
+    }
+);
+case!("Transfer.sol", Transfer, transfer_selfCall, transfer_self, amount: U256);
+
 sol!(
     contract MStore8 {
         function mStore8(uint value) public pure returns (uint256 word);

crates/integration/src/tests.rs

@@ -37,10 +37,10 @@ test_spec!(events, "Events", "Events.sol");
 test_spec!(storage, "Storage", "Storage.sol");
 test_spec!(mstore8, "MStore8", "MStore8.sol");
 test_spec!(address, "Context", "Context.sol");
-test_spec!(balance, "Value", "Value.sol");
+test_spec!(value, "Value", "Value.sol");
 test_spec!(create, "CreateB", "Create.sol");
 test_spec!(call, "Caller", "Call.sol");
-test_spec!(transfer, "Transfer", "Transfer.sol");
+test_spec!(balance, "Balance", "Balance.sol");
 test_spec!(return_data_oob, "ReturnDataOob", "ReturnDataOob.sol");
 test_spec!(immutables, "Immutables", "Immutables.sol");
 test_spec!(transaction, "Transaction", "Transaction.sol");
@@ -52,6 +52,8 @@ test_spec!(gas_limit, "GasLimit", "GasLimit.sol");
 test_spec!(base_fee, "BaseFee", "BaseFee.sol");
 test_spec!(coinbase, "Coinbase", "Coinbase.sol");
 test_spec!(create2, "CreateB", "Create2.sol");
+test_spec!(transfer, "Transfer", "Transfer.sol");
+test_spec!(send, "Send", "Send.sol");
 
 fn instantiate(path: &str, contract: &str) -> Vec<SpecsAction> {
     vec![Instantiate {
@@ -434,3 +436,47 @@ fn ext_code_size() {
     }
     .run();
 }
+
+#[test]
+#[should_panic(expected = "ReentranceDenied")]
+fn send_denies_reentrancy() {
+    let value = 1000;
+    Specs {
+        actions: vec![
+            instantiate("contracts/Send.sol", "Send").remove(0),
+            Call {
+                origin: TestAddress::Alice,
+                dest: TestAddress::Instantiated(0),
+                value,
+                gas_limit: None,
+                storage_deposit_limit: None,
+                data: Contract::send_self(U256::from(value)).calldata,
+            },
+        ],
+        differential: false,
+        ..Default::default()
+    }
+    .run();
+}
+
+#[test]
+#[should_panic(expected = "ReentranceDenied")]
+fn transfer_denies_reentrancy() {
+    let value = 1000;
+    Specs {
+        actions: vec![
+            instantiate("contracts/Transfer.sol", "Transfer").remove(0),
+            Call {
+                origin: TestAddress::Alice,
+                dest: TestAddress::Instantiated(0),
+                value,
+                gas_limit: None,
+                storage_deposit_limit: None,
+                data: Contract::transfer_self(U256::from(value)).calldata,
+            },
+        ],
+        differential: false,
+        ..Default::default()
+    }
+    .run();
+}