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Diffstat (limited to 'clang/lib/StaticAnalyzer/Checkers/MacOSKeychainAPIChecker.cpp')
| -rw-r--r-- | clang/lib/StaticAnalyzer/Checkers/MacOSKeychainAPIChecker.cpp | 681 |
1 files changed, 681 insertions, 0 deletions
diff --git a/clang/lib/StaticAnalyzer/Checkers/MacOSKeychainAPIChecker.cpp b/clang/lib/StaticAnalyzer/Checkers/MacOSKeychainAPIChecker.cpp new file mode 100644 index 0000000..cb976e0 --- /dev/null +++ b/clang/lib/StaticAnalyzer/Checkers/MacOSKeychainAPIChecker.cpp @@ -0,0 +1,681 @@ +//==--- MacOSKeychainAPIChecker.cpp ------------------------------*- C++ -*-==// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// This checker flags misuses of KeyChainAPI. In particular, the password data +// allocated/returned by SecKeychainItemCopyContent, +// SecKeychainFindGenericPassword, SecKeychainFindInternetPassword functions has +// to be freed using a call to SecKeychainItemFreeContent. +//===----------------------------------------------------------------------===// + +#include "ClangSACheckers.h" +#include "clang/StaticAnalyzer/Core/Checker.h" +#include "clang/StaticAnalyzer/Core/CheckerManager.h" +#include "clang/StaticAnalyzer/Core/BugReporter/BugType.h" +#include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h" +#include "clang/StaticAnalyzer/Core/PathSensitive/ProgramState.h" +#include "clang/StaticAnalyzer/Core/PathSensitive/ProgramStateTrait.h" +#include "llvm/ADT/SmallString.h" + +using namespace clang; +using namespace ento; + +namespace { +class MacOSKeychainAPIChecker : public Checker<check::PreStmt<CallExpr>, + check::PreStmt<ReturnStmt>, + check::PostStmt<CallExpr>, + check::EndPath, + check::DeadSymbols> { + mutable OwningPtr<BugType> BT; + +public: + /// AllocationState is a part of the checker specific state together with the + /// MemRegion corresponding to the allocated data. + struct AllocationState { + /// The index of the allocator function. + unsigned int AllocatorIdx; + SymbolRef Region; + + AllocationState(const Expr *E, unsigned int Idx, SymbolRef R) : + AllocatorIdx(Idx), + Region(R) {} + + bool operator==(const AllocationState &X) const { + return (AllocatorIdx == X.AllocatorIdx && + Region == X.Region); + } + + void Profile(llvm::FoldingSetNodeID &ID) const { + ID.AddInteger(AllocatorIdx); + ID.AddPointer(Region); + } + }; + + void checkPreStmt(const CallExpr *S, CheckerContext &C) const; + void checkPreStmt(const ReturnStmt *S, CheckerContext &C) const; + void checkPostStmt(const CallExpr *S, CheckerContext &C) const; + void checkDeadSymbols(SymbolReaper &SR, CheckerContext &C) const; + void checkEndPath(CheckerContext &C) const; + +private: + typedef std::pair<SymbolRef, const AllocationState*> AllocationPair; + typedef llvm::SmallVector<AllocationPair, 2> AllocationPairVec; + + enum APIKind { + /// Denotes functions tracked by this checker. + ValidAPI = 0, + /// The functions commonly/mistakenly used in place of the given API. + ErrorAPI = 1, + /// The functions which may allocate the data. These are tracked to reduce + /// the false alarm rate. + PossibleAPI = 2 + }; + /// Stores the information about the allocator and deallocator functions - + /// these are the functions the checker is tracking. + struct ADFunctionInfo { + const char* Name; + unsigned int Param; + unsigned int DeallocatorIdx; + APIKind Kind; + }; + static const unsigned InvalidIdx = 100000; + static const unsigned FunctionsToTrackSize = 8; + static const ADFunctionInfo FunctionsToTrack[FunctionsToTrackSize]; + /// The value, which represents no error return value for allocator functions. + static const unsigned NoErr = 0; + + /// Given the function name, returns the index of the allocator/deallocator + /// function. + static unsigned getTrackedFunctionIndex(StringRef Name, bool IsAllocator); + + inline void initBugType() const { + if (!BT) + BT.reset(new BugType("Improper use of SecKeychain API", "Mac OS API")); + } + + void generateDeallocatorMismatchReport(const AllocationPair &AP, + const Expr *ArgExpr, + CheckerContext &C) const; + + /// Find the allocation site for Sym on the path leading to the node N. + const Stmt *getAllocationSite(const ExplodedNode *N, SymbolRef Sym, + CheckerContext &C) const; + + BugReport *generateAllocatedDataNotReleasedReport(const AllocationPair &AP, + ExplodedNode *N, + CheckerContext &C) const; + + /// Check if RetSym evaluates to an error value in the current state. + bool definitelyReturnedError(SymbolRef RetSym, + ProgramStateRef State, + SValBuilder &Builder, + bool noError = false) const; + + /// Check if RetSym evaluates to a NoErr value in the current state. + bool definitelyDidnotReturnError(SymbolRef RetSym, + ProgramStateRef State, + SValBuilder &Builder) const { + return definitelyReturnedError(RetSym, State, Builder, true); + } + + /// Mark an AllocationPair interesting for diagnostic reporting. + void markInteresting(BugReport *R, const AllocationPair &AP) const { + R->markInteresting(AP.first); + R->markInteresting(AP.second->Region); + } + + /// The bug visitor which allows us to print extra diagnostics along the + /// BugReport path. For example, showing the allocation site of the leaked + /// region. + class SecKeychainBugVisitor + : public BugReporterVisitorImpl<SecKeychainBugVisitor> { + protected: + // The allocated region symbol tracked by the main analysis. + SymbolRef Sym; + + public: + SecKeychainBugVisitor(SymbolRef S) : Sym(S) {} + virtual ~SecKeychainBugVisitor() {} + + void Profile(llvm::FoldingSetNodeID &ID) const { + static int X = 0; + ID.AddPointer(&X); + ID.AddPointer(Sym); + } + + PathDiagnosticPiece *VisitNode(const ExplodedNode *N, + const ExplodedNode *PrevN, + BugReporterContext &BRC, + BugReport &BR); + }; +}; +} + +/// ProgramState traits to store the currently allocated (and not yet freed) +/// symbols. This is a map from the allocated content symbol to the +/// corresponding AllocationState. +typedef llvm::ImmutableMap<SymbolRef, + MacOSKeychainAPIChecker::AllocationState> AllocatedSetTy; + +namespace { struct AllocatedData {}; } +namespace clang { namespace ento { +template<> struct ProgramStateTrait<AllocatedData> + : public ProgramStatePartialTrait<AllocatedSetTy > { + static void *GDMIndex() { static int index = 0; return &index; } +}; +}} + +static bool isEnclosingFunctionParam(const Expr *E) { + E = E->IgnoreParenCasts(); + if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) { + const ValueDecl *VD = DRE->getDecl(); + if (isa<ImplicitParamDecl>(VD) || isa<ParmVarDecl>(VD)) + return true; + } + return false; +} + +const MacOSKeychainAPIChecker::ADFunctionInfo + MacOSKeychainAPIChecker::FunctionsToTrack[FunctionsToTrackSize] = { + {"SecKeychainItemCopyContent", 4, 3, ValidAPI}, // 0 + {"SecKeychainFindGenericPassword", 6, 3, ValidAPI}, // 1 + {"SecKeychainFindInternetPassword", 13, 3, ValidAPI}, // 2 + {"SecKeychainItemFreeContent", 1, InvalidIdx, ValidAPI}, // 3 + {"SecKeychainItemCopyAttributesAndData", 5, 5, ValidAPI}, // 4 + {"SecKeychainItemFreeAttributesAndData", 1, InvalidIdx, ValidAPI}, // 5 + {"free", 0, InvalidIdx, ErrorAPI}, // 6 + {"CFStringCreateWithBytesNoCopy", 1, InvalidIdx, PossibleAPI}, // 7 +}; + +unsigned MacOSKeychainAPIChecker::getTrackedFunctionIndex(StringRef Name, + bool IsAllocator) { + for (unsigned I = 0; I < FunctionsToTrackSize; ++I) { + ADFunctionInfo FI = FunctionsToTrack[I]; + if (FI.Name != Name) + continue; + // Make sure the function is of the right type (allocator vs deallocator). + if (IsAllocator && (FI.DeallocatorIdx == InvalidIdx)) + return InvalidIdx; + if (!IsAllocator && (FI.DeallocatorIdx != InvalidIdx)) + return InvalidIdx; + + return I; + } + // The function is not tracked. + return InvalidIdx; +} + +static bool isBadDeallocationArgument(const MemRegion *Arg) { + if (!Arg) + return false; + if (isa<AllocaRegion>(Arg) || + isa<BlockDataRegion>(Arg) || + isa<TypedRegion>(Arg)) { + return true; + } + return false; +} + +/// Given the address expression, retrieve the value it's pointing to. Assume +/// that value is itself an address, and return the corresponding symbol. +static SymbolRef getAsPointeeSymbol(const Expr *Expr, + CheckerContext &C) { + ProgramStateRef State = C.getState(); + SVal ArgV = State->getSVal(Expr, C.getLocationContext()); + + if (const loc::MemRegionVal *X = dyn_cast<loc::MemRegionVal>(&ArgV)) { + StoreManager& SM = C.getStoreManager(); + SymbolRef sym = SM.getBinding(State->getStore(), *X).getAsLocSymbol(); + if (sym) + return sym; + } + return 0; +} + +// When checking for error code, we need to consider the following cases: +// 1) noErr / [0] +// 2) someErr / [1, inf] +// 3) unknown +// If noError, returns true iff (1). +// If !noError, returns true iff (2). +bool MacOSKeychainAPIChecker::definitelyReturnedError(SymbolRef RetSym, + ProgramStateRef State, + SValBuilder &Builder, + bool noError) const { + DefinedOrUnknownSVal NoErrVal = Builder.makeIntVal(NoErr, + Builder.getSymbolManager().getType(RetSym)); + DefinedOrUnknownSVal NoErr = Builder.evalEQ(State, NoErrVal, + nonloc::SymbolVal(RetSym)); + ProgramStateRef ErrState = State->assume(NoErr, noError); + if (ErrState == State) { + return true; + } + + return false; +} + +// Report deallocator mismatch. Remove the region from tracking - reporting a +// missing free error after this one is redundant. +void MacOSKeychainAPIChecker:: + generateDeallocatorMismatchReport(const AllocationPair &AP, + const Expr *ArgExpr, + CheckerContext &C) const { + ProgramStateRef State = C.getState(); + State = State->remove<AllocatedData>(AP.first); + ExplodedNode *N = C.addTransition(State); + + if (!N) + return; + initBugType(); + SmallString<80> sbuf; + llvm::raw_svector_ostream os(sbuf); + unsigned int PDeallocIdx = + FunctionsToTrack[AP.second->AllocatorIdx].DeallocatorIdx; + + os << "Deallocator doesn't match the allocator: '" + << FunctionsToTrack[PDeallocIdx].Name << "' should be used."; + BugReport *Report = new BugReport(*BT, os.str(), N); + Report->addVisitor(new SecKeychainBugVisitor(AP.first)); + Report->addRange(ArgExpr->getSourceRange()); + markInteresting(Report, AP); + C.EmitReport(Report); +} + +void MacOSKeychainAPIChecker::checkPreStmt(const CallExpr *CE, + CheckerContext &C) const { + unsigned idx = InvalidIdx; + ProgramStateRef State = C.getState(); + + StringRef funName = C.getCalleeName(CE); + if (funName.empty()) + return; + + // If it is a call to an allocator function, it could be a double allocation. + idx = getTrackedFunctionIndex(funName, true); + if (idx != InvalidIdx) { + const Expr *ArgExpr = CE->getArg(FunctionsToTrack[idx].Param); + if (SymbolRef V = getAsPointeeSymbol(ArgExpr, C)) + if (const AllocationState *AS = State->get<AllocatedData>(V)) { + if (!definitelyReturnedError(AS->Region, State, C.getSValBuilder())) { + // Remove the value from the state. The new symbol will be added for + // tracking when the second allocator is processed in checkPostStmt(). + State = State->remove<AllocatedData>(V); + ExplodedNode *N = C.addTransition(State); + if (!N) + return; + initBugType(); + SmallString<128> sbuf; + llvm::raw_svector_ostream os(sbuf); + unsigned int DIdx = FunctionsToTrack[AS->AllocatorIdx].DeallocatorIdx; + os << "Allocated data should be released before another call to " + << "the allocator: missing a call to '" + << FunctionsToTrack[DIdx].Name + << "'."; + BugReport *Report = new BugReport(*BT, os.str(), N); + Report->addVisitor(new SecKeychainBugVisitor(V)); + Report->addRange(ArgExpr->getSourceRange()); + Report->markInteresting(AS->Region); + C.EmitReport(Report); + } + } + return; + } + + // Is it a call to one of deallocator functions? + idx = getTrackedFunctionIndex(funName, false); + if (idx == InvalidIdx) + return; + + // Check the argument to the deallocator. + const Expr *ArgExpr = CE->getArg(FunctionsToTrack[idx].Param); + SVal ArgSVal = State->getSVal(ArgExpr, C.getLocationContext()); + + // Undef is reported by another checker. + if (ArgSVal.isUndef()) + return; + + SymbolRef ArgSM = ArgSVal.getAsLocSymbol(); + + // If the argument is coming from the heap, globals, or unknown, do not + // report it. + bool RegionArgIsBad = false; + if (!ArgSM) { + if (!isBadDeallocationArgument(ArgSVal.getAsRegion())) + return; + RegionArgIsBad = true; + } + + // Is the argument to the call being tracked? + const AllocationState *AS = State->get<AllocatedData>(ArgSM); + if (!AS && FunctionsToTrack[idx].Kind != ValidAPI) { + return; + } + // If trying to free data which has not been allocated yet, report as a bug. + // TODO: We might want a more precise diagnostic for double free + // (that would involve tracking all the freed symbols in the checker state). + if (!AS || RegionArgIsBad) { + // It is possible that this is a false positive - the argument might + // have entered as an enclosing function parameter. + if (isEnclosingFunctionParam(ArgExpr)) + return; + + ExplodedNode *N = C.addTransition(State); + if (!N) + return; + initBugType(); + BugReport *Report = new BugReport(*BT, + "Trying to free data which has not been allocated.", N); + Report->addRange(ArgExpr->getSourceRange()); + if (AS) + Report->markInteresting(AS->Region); + C.EmitReport(Report); + return; + } + + // Process functions which might deallocate. + if (FunctionsToTrack[idx].Kind == PossibleAPI) { + + if (funName == "CFStringCreateWithBytesNoCopy") { + const Expr *DeallocatorExpr = CE->getArg(5)->IgnoreParenCasts(); + // NULL ~ default deallocator, so warn. + if (DeallocatorExpr->isNullPointerConstant(C.getASTContext(), + Expr::NPC_ValueDependentIsNotNull)) { + const AllocationPair AP = std::make_pair(ArgSM, AS); + generateDeallocatorMismatchReport(AP, ArgExpr, C); + return; + } + // One of the default allocators, so warn. + if (const DeclRefExpr *DE = dyn_cast<DeclRefExpr>(DeallocatorExpr)) { + StringRef DeallocatorName = DE->getFoundDecl()->getName(); + if (DeallocatorName == "kCFAllocatorDefault" || + DeallocatorName == "kCFAllocatorSystemDefault" || + DeallocatorName == "kCFAllocatorMalloc") { + const AllocationPair AP = std::make_pair(ArgSM, AS); + generateDeallocatorMismatchReport(AP, ArgExpr, C); + return; + } + // If kCFAllocatorNull, which does not deallocate, we still have to + // find the deallocator. Otherwise, assume that the user had written a + // custom deallocator which does the right thing. + if (DE->getFoundDecl()->getName() != "kCFAllocatorNull") { + State = State->remove<AllocatedData>(ArgSM); + C.addTransition(State); + return; + } + } + } + return; + } + + // The call is deallocating a value we previously allocated, so remove it + // from the next state. + State = State->remove<AllocatedData>(ArgSM); + + // Check if the proper deallocator is used. + unsigned int PDeallocIdx = FunctionsToTrack[AS->AllocatorIdx].DeallocatorIdx; + if (PDeallocIdx != idx || (FunctionsToTrack[idx].Kind == ErrorAPI)) { + const AllocationPair AP = std::make_pair(ArgSM, AS); + generateDeallocatorMismatchReport(AP, ArgExpr, C); + return; + } + + // If the buffer can be null and the return status can be an error, + // report a bad call to free. + if (State->assume(cast<DefinedSVal>(ArgSVal), false) && + !definitelyDidnotReturnError(AS->Region, State, C.getSValBuilder())) { + ExplodedNode *N = C.addTransition(State); + if (!N) + return; + initBugType(); + BugReport *Report = new BugReport(*BT, + "Only call free if a valid (non-NULL) buffer was returned.", N); + Report->addVisitor(new SecKeychainBugVisitor(ArgSM)); + Report->addRange(ArgExpr->getSourceRange()); + Report->markInteresting(AS->Region); + C.EmitReport(Report); + return; + } + + C.addTransition(State); +} + +void MacOSKeychainAPIChecker::checkPostStmt(const CallExpr *CE, + CheckerContext &C) const { + ProgramStateRef State = C.getState(); + StringRef funName = C.getCalleeName(CE); + + // If a value has been allocated, add it to the set for tracking. + unsigned idx = getTrackedFunctionIndex(funName, true); + if (idx == InvalidIdx) + return; + + const Expr *ArgExpr = CE->getArg(FunctionsToTrack[idx].Param); + // If the argument entered as an enclosing function parameter, skip it to + // avoid false positives. + if (isEnclosingFunctionParam(ArgExpr) && + C.getLocationContext()->getParent() == 0) + return; + + if (SymbolRef V = getAsPointeeSymbol(ArgExpr, C)) { + // If the argument points to something that's not a symbolic region, it + // can be: + // - unknown (cannot reason about it) + // - undefined (already reported by other checker) + // - constant (null - should not be tracked, + // other constant will generate a compiler warning) + // - goto (should be reported by other checker) + + // The call return value symbol should stay alive for as long as the + // allocated value symbol, since our diagnostics depend on the value + // returned by the call. Ex: Data should only be freed if noErr was + // returned during allocation.) + SymbolRef RetStatusSymbol = + State->getSVal(CE, C.getLocationContext()).getAsSymbol(); + C.getSymbolManager().addSymbolDependency(V, RetStatusSymbol); + + // Track the allocated value in the checker state. + State = State->set<AllocatedData>(V, AllocationState(ArgExpr, idx, + RetStatusSymbol)); + assert(State); + C.addTransition(State); + } +} + +void MacOSKeychainAPIChecker::checkPreStmt(const ReturnStmt *S, + CheckerContext &C) const { + const Expr *retExpr = S->getRetValue(); + if (!retExpr) + return; + + // If inside inlined call, skip it. + const LocationContext *LC = C.getLocationContext(); + if (LC->getParent() != 0) + return; + + // Check if the value is escaping through the return. + ProgramStateRef state = C.getState(); + SymbolRef sym = state->getSVal(retExpr, LC).getAsLocSymbol(); + if (!sym) + return; + state = state->remove<AllocatedData>(sym); + + // Proceed from the new state. + C.addTransition(state); +} + +// TODO: This logic is the same as in Malloc checker. +const Stmt * +MacOSKeychainAPIChecker::getAllocationSite(const ExplodedNode *N, + SymbolRef Sym, + CheckerContext &C) const { + const LocationContext *LeakContext = N->getLocationContext(); + // Walk the ExplodedGraph backwards and find the first node that referred to + // the tracked symbol. + const ExplodedNode *AllocNode = N; + + while (N) { + if (!N->getState()->get<AllocatedData>(Sym)) + break; + // Allocation node, is the last node in the current context in which the + // symbol was tracked. + if (N->getLocationContext() == LeakContext) + AllocNode = N; + N = N->pred_empty() ? NULL : *(N->pred_begin()); + } + + ProgramPoint P = AllocNode->getLocation(); + if (!isa<StmtPoint>(P)) + return 0; + return cast<clang::PostStmt>(P).getStmt(); +} + +BugReport *MacOSKeychainAPIChecker:: + generateAllocatedDataNotReleasedReport(const AllocationPair &AP, + ExplodedNode *N, + CheckerContext &C) const { + const ADFunctionInfo &FI = FunctionsToTrack[AP.second->AllocatorIdx]; + initBugType(); + SmallString<70> sbuf; + llvm::raw_svector_ostream os(sbuf); + os << "Allocated data is not released: missing a call to '" + << FunctionsToTrack[FI.DeallocatorIdx].Name << "'."; + + // Most bug reports are cached at the location where they occurred. + // With leaks, we want to unique them by the location where they were + // allocated, and only report a single path. + PathDiagnosticLocation LocUsedForUniqueing; + if (const Stmt *AllocStmt = getAllocationSite(N, AP.first, C)) + LocUsedForUniqueing = PathDiagnosticLocation::createBegin(AllocStmt, + C.getSourceManager(), N->getLocationContext()); + + BugReport *Report = new BugReport(*BT, os.str(), N, LocUsedForUniqueing); + Report->addVisitor(new SecKeychainBugVisitor(AP.first)); + markInteresting(Report, AP); + return Report; +} + +void MacOSKeychainAPIChecker::checkDeadSymbols(SymbolReaper &SR, + CheckerContext &C) const { + ProgramStateRef State = C.getState(); + AllocatedSetTy ASet = State->get<AllocatedData>(); + if (ASet.isEmpty()) + return; + + bool Changed = false; + AllocationPairVec Errors; + for (AllocatedSetTy::iterator I = ASet.begin(), E = ASet.end(); I != E; ++I) { + if (SR.isLive(I->first)) + continue; + + Changed = true; + State = State->remove<AllocatedData>(I->first); + // If the allocated symbol is null or if the allocation call might have + // returned an error, do not report. + if (State->getSymVal(I->first) || + definitelyReturnedError(I->second.Region, State, C.getSValBuilder())) + continue; + Errors.push_back(std::make_pair(I->first, &I->second)); + } + if (!Changed) { + // Generate the new, cleaned up state. + C.addTransition(State); + return; + } + + static SimpleProgramPointTag Tag("MacOSKeychainAPIChecker : DeadSymbolsLeak"); + ExplodedNode *N = C.addTransition(C.getState(), C.getPredecessor(), &Tag); + + // Generate the error reports. + for (AllocationPairVec::iterator I = Errors.begin(), E = Errors.end(); + I != E; ++I) { + C.EmitReport(generateAllocatedDataNotReleasedReport(*I, N, C)); + } + + // Generate the new, cleaned up state. + C.addTransition(State, N); +} + +// TODO: Remove this after we ensure that checkDeadSymbols are always called. +void MacOSKeychainAPIChecker::checkEndPath(CheckerContext &C) const { + ProgramStateRef state = C.getState(); + + // If inside inlined call, skip it. + if (C.getLocationContext()->getParent() != 0) + return; + + AllocatedSetTy AS = state->get<AllocatedData>(); + if (AS.isEmpty()) + return; + + // Anything which has been allocated but not freed (nor escaped) will be + // found here, so report it. + bool Changed = false; + AllocationPairVec Errors; + for (AllocatedSetTy::iterator I = AS.begin(), E = AS.end(); I != E; ++I ) { + Changed = true; + state = state->remove<AllocatedData>(I->first); + // If the allocated symbol is null or if error code was returned at + // allocation, do not report. + if (state->getSymVal(I.getKey()) || + definitelyReturnedError(I->second.Region, state, + C.getSValBuilder())) { + continue; + } + Errors.push_back(std::make_pair(I->first, &I->second)); + } + + // If no change, do not generate a new state. + if (!Changed) { + C.addTransition(state); + return; + } + + static SimpleProgramPointTag Tag("MacOSKeychainAPIChecker : EndPathLeak"); + ExplodedNode *N = C.addTransition(C.getState(), C.getPredecessor(), &Tag); + + // Generate the error reports. + for (AllocationPairVec::iterator I = Errors.begin(), E = Errors.end(); + I != E; ++I) { + C.EmitReport(generateAllocatedDataNotReleasedReport(*I, N, C)); + } + + C.addTransition(state, N); +} + + +PathDiagnosticPiece *MacOSKeychainAPIChecker::SecKeychainBugVisitor::VisitNode( + const ExplodedNode *N, + const ExplodedNode *PrevN, + BugReporterContext &BRC, + BugReport &BR) { + const AllocationState *AS = N->getState()->get<AllocatedData>(Sym); + if (!AS) + return 0; + const AllocationState *ASPrev = PrevN->getState()->get<AllocatedData>(Sym); + if (ASPrev) + return 0; + + // (!ASPrev && AS) ~ We started tracking symbol in node N, it must be the + // allocation site. + const CallExpr *CE = cast<CallExpr>(cast<StmtPoint>(N->getLocation()) + .getStmt()); + const FunctionDecl *funDecl = CE->getDirectCallee(); + assert(funDecl && "We do not support indirect function calls as of now."); + StringRef funName = funDecl->getName(); + + // Get the expression of the corresponding argument. + unsigned Idx = getTrackedFunctionIndex(funName, true); + assert(Idx != InvalidIdx && "This should be a call to an allocator."); + const Expr *ArgExpr = CE->getArg(FunctionsToTrack[Idx].Param); + PathDiagnosticLocation Pos(ArgExpr, BRC.getSourceManager(), + N->getLocationContext()); + return new PathDiagnosticEventPiece(Pos, "Data is allocated here."); +} + +void ento::registerMacOSKeychainAPIChecker(CheckerManager &mgr) { + mgr.registerChecker<MacOSKeychainAPIChecker>(); +} |