1 //== TaintTesterChecker.cpp ----------------------------------- -*- C++ -*--=//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This checker can be used for testing how taint data is propagated.
11 //
12 //===----------------------------------------------------------------------===//
13 #include "ClangSACheckers.h"
14 #include "clang/StaticAnalyzer/Core/BugReporter/BugType.h"
15 #include "clang/StaticAnalyzer/Core/Checker.h"
16 #include "clang/StaticAnalyzer/Core/CheckerManager.h"
17 #include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h"
18 
19 using namespace clang;
20 using namespace ento;
21 
22 namespace {
23 class TaintTesterChecker : public Checker< check::PostStmt<Expr> > {
24 
25   mutable std::unique_ptr<BugType> BT;
26   void initBugType() const;
27 
28   /// Given a pointer argument, get the symbol of the value it contains
29   /// (points to).
30   SymbolRef getPointedToSymbol(CheckerContext &C,
31                                const Expr* Arg,
32                                bool IssueWarning = true) const;
33 
34 public:
35   void checkPostStmt(const Expr *E, CheckerContext &C) const;
36 };
37 }
38 
initBugType() const39 inline void TaintTesterChecker::initBugType() const {
40   if (!BT)
41     BT.reset(new BugType(this, "Tainted data", "General"));
42 }
43 
checkPostStmt(const Expr * E,CheckerContext & C) const44 void TaintTesterChecker::checkPostStmt(const Expr *E,
45                                        CheckerContext &C) const {
46   ProgramStateRef State = C.getState();
47   if (!State)
48     return;
49 
50   if (State->isTainted(E, C.getLocationContext())) {
51     if (ExplodedNode *N = C.addTransition()) {
52       initBugType();
53       BugReport *report = new BugReport(*BT, "tainted",N);
54       report->addRange(E->getSourceRange());
55       C.emitReport(report);
56     }
57   }
58 }
59 
registerTaintTesterChecker(CheckerManager & mgr)60 void ento::registerTaintTesterChecker(CheckerManager &mgr) {
61   mgr.registerChecker<TaintTesterChecker>();
62 }
63