//=== Taint.h - Taint tracking and basic propagation rules. --------*- C++ -*-//
 
//
 
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 
// See https://llvm.org/LICENSE.txt for license information.
 
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 
//
 
//===----------------------------------------------------------------------===//
 
//
 
// Defines basic, non-domain-specific mechanisms for tracking tainted values.
 
//
 
//===----------------------------------------------------------------------===//
 
 
 
#ifndef LLVM_CLANG_LIB_STATICANALYZER_CHECKERS_TAINT_H
 
#define LLVM_CLANG_LIB_STATICANALYZER_CHECKERS_TAINT_H
 
 
 
#include "clang/StaticAnalyzer/Core/BugReporter/BugReporterVisitors.h"
 
#include "clang/StaticAnalyzer/Core/PathSensitive/ProgramState.h"
 
 
 
namespace clang {
 
namespace ento {
 
namespace taint {
 
 
 
/// The type of taint, which helps to differentiate between different types of
 
/// taint.
 
using TaintTagType = unsigned;
 
 
 
static constexpr TaintTagType TaintTagGeneric = 0;
 
 
 
/// Create a new state in which the value of the statement is marked as tainted.
 
[[nodiscard]] ProgramStateRef addTaint(ProgramStateRef State, const Stmt *S,
 
                                       const LocationContext *LCtx,
 
                                       TaintTagType Kind = TaintTagGeneric);
 
 
 
/// Create a new state in which the value is marked as tainted.
 
[[nodiscard]] ProgramStateRef addTaint(ProgramStateRef State, SVal V,
 
                                       TaintTagType Kind = TaintTagGeneric);
 
 
 
/// Create a new state in which the symbol is marked as tainted.
 
[[nodiscard]] ProgramStateRef addTaint(ProgramStateRef State, SymbolRef Sym,
 
                                       TaintTagType Kind = TaintTagGeneric);
 
 
 
/// Create a new state in which the pointer represented by the region
 
/// is marked as tainted.
 
[[nodiscard]] ProgramStateRef addTaint(ProgramStateRef State,
 
                                       const MemRegion *R,
 
                                       TaintTagType Kind = TaintTagGeneric);
 
 
 
[[nodiscard]] ProgramStateRef removeTaint(ProgramStateRef State, SVal V);
 
 
 
[[nodiscard]] ProgramStateRef removeTaint(ProgramStateRef State,
 
                                          const MemRegion *R);
 
 
 
[[nodiscard]] ProgramStateRef removeTaint(ProgramStateRef State, SymbolRef Sym);
 
 
 
/// Create a new state in a which a sub-region of a given symbol is tainted.
 
/// This might be necessary when referring to regions that can not have an
 
/// individual symbol, e.g. if they are represented by the default binding of
 
/// a LazyCompoundVal.
 
[[nodiscard]] ProgramStateRef
 
addPartialTaint(ProgramStateRef State, SymbolRef ParentSym,
 
                const SubRegion *SubRegion,
 
                TaintTagType Kind = TaintTagGeneric);
 
 
 
/// Check if the statement has a tainted value in the given state.
 
bool isTainted(ProgramStateRef State, const Stmt *S,
 
               const LocationContext *LCtx,
 
               TaintTagType Kind = TaintTagGeneric);
 
 
 
/// Check if the value is tainted in the given state.
 
bool isTainted(ProgramStateRef State, SVal V,
 
               TaintTagType Kind = TaintTagGeneric);
 
 
 
/// Check if the symbol is tainted in the given state.
 
bool isTainted(ProgramStateRef State, SymbolRef Sym,
 
               TaintTagType Kind = TaintTagGeneric);
 
 
 
/// Check if the pointer represented by the region is tainted in the given
 
/// state.
 
bool isTainted(ProgramStateRef State, const MemRegion *Reg,
 
               TaintTagType Kind = TaintTagGeneric);
 
 
 
void printTaint(ProgramStateRef State, raw_ostream &Out, const char *nl = "\n",
 
                const char *sep = "");
 
 
 
LLVM_DUMP_METHOD void dumpTaint(ProgramStateRef State);
 
 
 
/// The bug visitor prints a diagnostic message at the location where a given
 
/// variable was tainted.
 
class TaintBugVisitor final : public BugReporterVisitor {
 
private:
 
  const SVal V;
 
 
 
public:
 
  TaintBugVisitor(const SVal V) : V(V) {}
 
  void Profile(llvm::FoldingSetNodeID &ID) const override { ID.Add(V); }
 
 
 
  PathDiagnosticPieceRef VisitNode(const ExplodedNode *N,
 
                                   BugReporterContext &BRC,
 
                                   PathSensitiveBugReport &BR) override;
 
};
 
 
 
} // namespace taint
 
} // namespace ento
 
} // namespace clang
 
 
 
#endif