C++: Add a MaD model for 'CRegKey' and mark query calls as local flow sources.

cpp/ql/lib/ext/CRegKey.model.yml

@@ -0,0 +1,19 @@
+extensions:
+  - addsTo:
+      pack: codeql/cpp-all
+      extensible: summaryModel
+    data: # namespace, type, subtypes, name, signature, ext, input, output, kind, provenance
+      - ["", "CRegKey", True, "CRegKey", "(CRegKey&)", "", "Argument[*0]", "Argument[-1]", "value", "manual"]
+      - ["", "CRegKey", True, "CRegKey", "(HKEY)", "", "Argument[0]", "Argument[-1]", "taint", "manual"]
+      - ["", "CRegKey", True, "Attach", "", "", "Argument[0]", "Argument[-1]", "taint", "manual"]
+      - ["", "CRegKey", True, "QueryBinaryValue", "", "", "Argument[*0]", "Argument[*1]", "taint", "manual"]
+      - ["", "CRegKey", True, "QueryDWORDValue", "", "", "Argument[*0]", "Argument[*1]", "taint", "manual"]
+      - ["", "CRegKey", True, "QueryMultiStringValue", "", "", "Argument[*0]", "Argument[**1]", "taint", "manual"]
+      - ["", "CRegKey", True, "QueryQWORDValue", "", "", "Argument[*0]", "Argument[*1]", "taint", "manual"]
+      - ["", "CRegKey", True, "QueryStringValue", "", "", "Argument[*0]", "Argument[**1]", "taint", "manual"]
+      - ["", "CRegKey", True, "QueryValue", "(LPCTSTR,DWORD *,void *,ULONG *)", "", "Argument[*0]", "Argument[*2]", "taint", "manual"]
+      - ["", "CRegKey", True, "QueryValue", "(DWORD&,LPCTSTR)", "", "Argument[*1]", "Argument[*0]", "taint", "manual"]
+      - ["", "CRegKey", True, "QueryValue", "(LPTSTR,LPCTSTR,DWORD *)", "", "Argument[*1]", "Argument[**0]", "taint", "manual"]
+      - ["", "CRegKey", True, "QueryValue", "operator HKEY", "", "Argument[-1]", "ReturnValue", "taint", "manual"]
+      - ["", "CRegKey", True, "QueryValue", "operator=", "", "Argument[*0]", "ReturnValue[*]", "value", "manual"]
+      - ["", "CRegKey", True, "QueryValue", "operator=", "", "Argument[*0]", "Argument[-1]", "value", "manual"]

cpp/ql/lib/semmle/code/cpp/models/Models.qll

@@ -56,3 +56,4 @@ private import implementations.CPathT
 private import implementations.CAtlFile
 private import implementations.CAtlFileMapping
 private import implementations.CAtlTemporaryFile
+private import implementations.CRegKey

cpp/ql/lib/semmle/code/cpp/models/implementations/CRegKey.qll

@@ -0,0 +1,87 @@
+private import cpp
+private import semmle.code.cpp.models.interfaces.FlowSource
+private import semmle.code.cpp.ir.dataflow.FlowSteps
+private import semmle.code.cpp.dataflow.new.DataFlow
+
+/** The `CRegKey` class from the Microsoft "Active Template Library". */
+class CRegKey extends Class {
+  CRegKey() { this.hasGlobalName("CRegKey") }
+}
+
+module CRegKey {
+  /** The `m_hKey` member on a object of type `CRegKey`. */
+  class MhKey extends Field {
+    MhKey() {
+      this.getDeclaringType() instanceof CRegKey and
+      this.getName() = "m_hKey"
+    }
+  }
+
+  private class MhKeyPathTaintInheritingContent extends TaintInheritingContent,
+    DataFlow::FieldContent
+  {
+    MhKeyPathTaintInheritingContent() { this.getField() instanceof MhKey }
+  }
+
+  private class CRegKeyMemberFunction extends MemberFunction {
+    string name;
+
+    CRegKeyMemberFunction() { this.getClassAndName(name) instanceof CRegKey }
+  }
+
+  abstract private class CRegKeyFlowSource extends CRegKeyMemberFunction, LocalFlowSourceFunction {
+    FunctionOutput output;
+
+    final override predicate hasLocalFlowSource(FunctionOutput output_, string description) {
+      output_ = output and
+      description = "registry string read by " + name
+    }
+  }
+
+  /** The `CRegKey::QueryBinaryValue` function from Win32. */
+  class QueryBinaryValue extends CRegKeyFlowSource {
+    QueryBinaryValue() { name = "QueryBinaryValue" and output.isParameterDeref(1) }
+  }
+
+  /** The `CRegKey::QueryDWORDValue` function from Win32. */
+  class QueryDwordValue extends CRegKeyFlowSource {
+    QueryDwordValue() { name = "QueryDWORDValue" and output.isParameterDeref(1) }
+  }
+
+  /** The `CRegKey::QueryGUIDValue` function from Win32. */
+  class QueryGuidValue extends CRegKeyFlowSource {
+    QueryGuidValue() { name = "QueryGUIDValue" and output.isParameterDeref(1) }
+  }
+
+  /** The `CRegKey::QueryMultiStringValue` function from Win32. */
+  class QueryMultiStringValue extends CRegKeyFlowSource {
+    QueryMultiStringValue() { name = "QueryMultiStringValue" and output.isParameterDeref(1) }
+  }
+
+  /** The `CRegKey::QueryQWORDValue` function from Win32. */
+  class QueryQwordValue extends CRegKeyFlowSource {
+    QueryQwordValue() { name = "QueryQWORDValue" and output.isParameterDeref(1) }
+  }
+
+  /** The `CRegKey::QueryStringValue` function from Win32. */
+  class QueryStringValue extends CRegKeyFlowSource {
+    QueryStringValue() { name = "QueryStringValue" and output.isParameterDeref(1) }
+  }
+
+  /** The `CRegKey::QueryValue` function from Win32. */
+  class QueryValue extends CRegKeyFlowSource {
+    QueryValue() {
+      name = "QueryValue" and
+      (
+        this.getNumberOfParameters() = 4 and
+        output.isParameterDeref(2)
+        or
+        this.getNumberOfParameters() = 2 and
+        output.isParameterDeref(0)
+        or
+        this.getNumberOfParameters() = 3 and
+        output.isParameterDeref(0)
+      )
+    }
+  }
+}

cpp/ql/test/library-tests/dataflow/source-sink-tests/atl.cpp

@@ -364,26 +364,26 @@ void test_CRegKey() {
   CRegKey key;
   char data[1024];
   ULONG bytesRead;
-  key.QueryBinaryValue("foo", data, &bytesRead); // $ MISSING: local_source
+  key.QueryBinaryValue("foo", data, &bytesRead); // $ local_source
 
   DWORD value;
-  key.QueryDWORDValue("foo", value); // $ MISSING: local_source
+  key.QueryDWORDValue("foo", value); // $ local_source
   
   GUID guid;
-  key.QueryGUIDValue("foo", guid); // $ MISSING: local_source
+  key.QueryGUIDValue("foo", guid); // $ local_source
   
-  key.QueryMultiStringValue("foo", data, &bytesRead); // $ MISSING: local_source
+  key.QueryMultiStringValue("foo", data, &bytesRead); // $ local_source
   
   ULONGLONG qword;
-  key.QueryQWORDValue("foo", qword); // $ MISSING: local_source
+  key.QueryQWORDValue("foo", qword); // $ local_source
   
-  key.QueryStringValue("foo", data, &bytesRead); // $ MISSING: local_source
+  key.QueryStringValue("foo", data, &bytesRead); // $ local_source
   
-  key.QueryValue(data, "foo", &bytesRead); // $ MISSING: local_source
+  key.QueryValue(data, "foo", &bytesRead); // $ local_source
   
   DWORD type;
-  key.QueryValue("foo", &type, data, &bytesRead); // $ MISSING: local_source
+  key.QueryValue("foo", &type, data, &bytesRead); // $ local_source
   
   DWORD value2;
-  key.QueryValue(value2, "foo"); // $ MISSING: local_source
+  key.QueryValue(value2, "foo"); // $ local_source
 }