Add support to older solc versions (#1726)

mythril/solidity/soliditycontract.py

@@ -11,6 +11,65 @@ from mythril.exceptions import NoContractFoundError
 log = logging.getLogger(__name__)
 
 
+class SolcAST:
+    def __init__(self, ast):
+        self.ast = ast
+
+    @property
+    def node_type(self):
+        if "nodeType" in self.ast:
+            return self.ast["nodeType"]
+        if "name" in self.ast:
+            return self.ast["name"]
+        assert False, "Unknown AST type has been fed to SolcAST"
+
+    @property
+    def abs_path(self):
+        if "absolutePath" in self.ast:
+            return self.ast["absolutePath"]
+        else:
+            return None
+
+    @property
+    def nodes(self):
+        if "nodes" in self.ast:
+            return self.ast["nodes"]
+        if "children" in self.ast:
+            return self.ast["children"]
+        assert False, "Unknown AST type has been fed to SolcAST"
+
+    def __next__(self):
+        yield self.ast.__next__()
+
+    def __getitem__(self, item):
+        return self.ast[item]
+
+
+class SolcSource:
+    def __init__(self, source):
+        self.source = source
+
+    @property
+    def ast(self):
+        if "ast" in self.source:
+            return SolcAST(self.source["ast"])
+        if "legacyAST" in self.source:
+            return SolcAST(self.source["legacyAST"])
+        assert False, "Unknown source type has been fed to SolcSource"
+
+    @property
+    def id(self):
+        return self.source["id"]
+
+    @property
+    def name(self):
+        return self.source["name"]
+
+    @property
+    def contents(self):
+        return self.source["contents"]
+
+
 class SourceMapping:
     def __init__(self, solidity_file_idx, offset, length, lineno, mapping):
         """Representation of a source mapping for a Solidity file."""
@@ -87,7 +146,7 @@ class SolidityContract(EVMContract):
             input_file, solc_settings_json=solc_settings_json, solc_binary=solc_binary
         )
 
-        self.solc_indices = self.get_solc_indices(data)
+        self.solc_indices = self.get_solc_indices(input_file, data)
         self.solc_json = data
         self.input_file = input_file
         has_contract = False
@@ -135,21 +194,22 @@ class SolidityContract(EVMContract):
     @staticmethod
     def get_sources(indices_data: Dict, source_data: Dict) -> None:
         """
-        Get source indices mapping
+        Get source indices mapping. Function not needed for older solc versions.
         """
+
         if "generatedSources" not in source_data:
             return
         sources = source_data["generatedSources"]
         for source in sources:
             full_contract_src_maps = SolidityContract.get_full_contract_src_maps(
-                source["ast"]
+                SolcAST(source["ast"])
             )
             indices_data[source["id"]] = SolidityFile(
                 source["name"], source["contents"], full_contract_src_maps
             )
 
     @staticmethod
-    def get_solc_indices(data: Dict) -> Dict:
+    def get_solc_indices(input_file: str, data: Dict) -> Dict:
         """
         Returns solc file indices
         """
@@ -161,31 +221,38 @@ class SolidityContract(EVMContract):
                     indices, source_data["evm"]["deployedBytecode"]
                 )
         for source in data["sources"].values():
+            source = SolcSource(source)
             full_contract_src_maps = SolidityContract.get_full_contract_src_maps(
-                source["ast"]
+                source.ast
             )
-            with open(source["ast"]["absolutePath"], "rb") as f:
+            if source.ast.abs_path is not None:
+                abs_path = source.ast.abs_path
+            else:
+                abs_path = input_file
+
+            with open(abs_path, "rb") as f:
                 code = f.read()
-                indices[source["id"]] = SolidityFile(
-                    source["ast"]["absolutePath"],
+                indices[source.id] = SolidityFile(
+                    abs_path,
                     code.decode("utf-8"),
                     full_contract_src_maps,
                 )
         return indices
 
     @staticmethod
-    def get_full_contract_src_maps(ast: Dict) -> Set[str]:
+    def get_full_contract_src_maps(ast: SolcAST) -> Set[str]:
         """
         Takes a solc AST and gets the src mappings for all the contracts defined in the top level of the ast
         :param ast: AST of the contract
         :return: The source maps
         """
+        print
         source_maps = set()
-        if ast["nodeType"] == "SourceUnit":
-            for child in ast["nodes"]:
+        if ast.node_type == "SourceUnit":
+            for child in ast.nodes:
                 if child.get("contractKind"):
                     source_maps.add(child["src"])
-        elif ast["nodeType"] == "YulBlock":
+        elif ast.node_type == "YulBlock":
             for child in ast["statements"]:
                 source_maps.add(child["src"])
 

tests/integration_tests/old_version_test.py

@@ -0,0 +1,20 @@
+import pytest
+import json
+import sys
+
+from tests import PROJECT_DIR, TESTDATA
+from utils import output_of
+
+MYTH = str(PROJECT_DIR / "myth")
+test_data = (
+    ("old_origin.sol", 1),
+    ("old_version.sol", 2),
+)
+
+
+@pytest.mark.parametrize("file_name, issues", test_data)
+def test_analysis_old(file_name, issues):
+    file = str(TESTDATA / "input_contracts" / file_name)
+    command = f"python3 {MYTH} analyze {file} -o jsonv2"
+    output = json.loads(output_of(command))
+    assert len(output[0]["issues"]) == issues

tests/testdata/input_contracts/old_origin.sol

@@ -0,0 +1,36 @@
+pragma solidity ^0.4.11;
+
+
+contract Origin {
+  address public owner;
+
+
+  /**
+   * @dev The Ownable constructor sets the original `owner` of the contract to the sender
+   * account.
+   */
+  function Origin()  {
+    owner = msg.sender;
+  }
+
+
+  /**
+   * @dev Throws if called by any account other than the owner.
+   */
+  modifier onlyOwner() {
+    require(tx.origin != owner);
+    _;
+  }
+
+
+  /**
+   * @dev Allows the current owner to transfer control of the contract to a newOwner.
+   * @param newOwner The address to transfer ownership to.
+   */
+  function transferOwnership(address newOwner) public onlyOwner {
+    if (newOwner != address(0)) {
+      owner = newOwner;
+    }
+  }
+
+}

tests/testdata/input_contracts/old_version.sol

@@ -0,0 +1,2 @@
+pragma solidity 0.4.11;
+contract test { }