MacOSKeychainAPIChecker.cpp revision 1437425a62dbf7bdb0a855d3ed3b05ed2019ec1e
1//==--- MacOSKeychainAPIChecker.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// This checker flags misuses of KeyChainAPI. In particular, the password data 10// allocated/returned by SecKeychainItemCopyContent, 11// SecKeychainFindGenericPassword, SecKeychainFindInternetPassword functions has 12// to be freed using a call to SecKeychainItemFreeContent. 13//===----------------------------------------------------------------------===// 14 15#include "ClangSACheckers.h" 16#include "clang/StaticAnalyzer/Core/Checker.h" 17#include "clang/StaticAnalyzer/Core/CheckerManager.h" 18#include "clang/StaticAnalyzer/Core/BugReporter/BugType.h" 19#include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h" 20#include "clang/StaticAnalyzer/Core/PathSensitive/ProgramState.h" 21#include "clang/StaticAnalyzer/Core/PathSensitive/ProgramStateTrait.h" 22 23using namespace clang; 24using namespace ento; 25 26namespace { 27class MacOSKeychainAPIChecker : public Checker<check::PreStmt<CallExpr>, 28 check::PreStmt<ReturnStmt>, 29 check::PostStmt<CallExpr>, 30 check::EndPath, 31 check::DeadSymbols> { 32 mutable llvm::OwningPtr<BugType> BT; 33 34public: 35 /// AllocationState is a part of the checker specific state together with the 36 /// MemRegion corresponding to the allocated data. 37 struct AllocationState { 38 /// The index of the allocator function. 39 unsigned int AllocatorIdx; 40 SymbolRef Region; 41 42 AllocationState(const Expr *E, unsigned int Idx, SymbolRef R) : 43 AllocatorIdx(Idx), 44 Region(R) {} 45 46 bool operator==(const AllocationState &X) const { 47 return (AllocatorIdx == X.AllocatorIdx && 48 Region == X.Region); 49 } 50 51 void Profile(llvm::FoldingSetNodeID &ID) const { 52 ID.AddInteger(AllocatorIdx); 53 ID.AddPointer(Region); 54 } 55 }; 56 57 void checkPreStmt(const CallExpr *S, CheckerContext &C) const; 58 void checkPreStmt(const ReturnStmt *S, CheckerContext &C) const; 59 void checkPostStmt(const CallExpr *S, CheckerContext &C) const; 60 void checkDeadSymbols(SymbolReaper &SR, CheckerContext &C) const; 61 void checkEndPath(CheckerContext &Ctx) const; 62 63private: 64 typedef std::pair<SymbolRef, const AllocationState*> AllocationPair; 65 typedef llvm::SmallVector<AllocationPair, 2> AllocationPairVec; 66 67 enum APIKind { 68 /// Denotes functions tracked by this checker. 69 ValidAPI = 0, 70 /// The functions commonly/mistakenly used in place of the given API. 71 ErrorAPI = 1, 72 /// The functions which may allocate the data. These are tracked to reduce 73 /// the false alarm rate. 74 PossibleAPI = 2 75 }; 76 /// Stores the information about the allocator and deallocator functions - 77 /// these are the functions the checker is tracking. 78 struct ADFunctionInfo { 79 const char* Name; 80 unsigned int Param; 81 unsigned int DeallocatorIdx; 82 APIKind Kind; 83 }; 84 static const unsigned InvalidIdx = 100000; 85 static const unsigned FunctionsToTrackSize = 8; 86 static const ADFunctionInfo FunctionsToTrack[FunctionsToTrackSize]; 87 /// The value, which represents no error return value for allocator functions. 88 static const unsigned NoErr = 0; 89 90 /// Given the function name, returns the index of the allocator/deallocator 91 /// function. 92 static unsigned getTrackedFunctionIndex(StringRef Name, bool IsAllocator); 93 94 inline void initBugType() const { 95 if (!BT) 96 BT.reset(new BugType("Improper use of SecKeychain API", "Mac OS API")); 97 } 98 99 void generateDeallocatorMismatchReport(const AllocationPair &AP, 100 const Expr *ArgExpr, 101 CheckerContext &C) const; 102 103 BugReport *generateAllocatedDataNotReleasedReport(const AllocationPair &AP, 104 ExplodedNode *N) const; 105 106 /// Check if RetSym evaluates to an error value in the current state. 107 bool definitelyReturnedError(SymbolRef RetSym, 108 const ProgramState *State, 109 SValBuilder &Builder, 110 bool noError = false) const; 111 112 /// Check if RetSym evaluates to a NoErr value in the current state. 113 bool definitelyDidnotReturnError(SymbolRef RetSym, 114 const ProgramState *State, 115 SValBuilder &Builder) const { 116 return definitelyReturnedError(RetSym, State, Builder, true); 117 } 118 119 /// The bug visitor which allows us to print extra diagnostics along the 120 /// BugReport path. For example, showing the allocation site of the leaked 121 /// region. 122 class SecKeychainBugVisitor : public BugReporterVisitor { 123 protected: 124 // The allocated region symbol tracked by the main analysis. 125 SymbolRef Sym; 126 127 public: 128 SecKeychainBugVisitor(SymbolRef S) : Sym(S) {} 129 virtual ~SecKeychainBugVisitor() {} 130 131 void Profile(llvm::FoldingSetNodeID &ID) const { 132 static int X = 0; 133 ID.AddPointer(&X); 134 ID.AddPointer(Sym); 135 } 136 137 PathDiagnosticPiece *VisitNode(const ExplodedNode *N, 138 const ExplodedNode *PrevN, 139 BugReporterContext &BRC, 140 BugReport &BR); 141 }; 142}; 143} 144 145/// ProgramState traits to store the currently allocated (and not yet freed) 146/// symbols. This is a map from the allocated content symbol to the 147/// corresponding AllocationState. 148typedef llvm::ImmutableMap<SymbolRef, 149 MacOSKeychainAPIChecker::AllocationState> AllocatedSetTy; 150 151namespace { struct AllocatedData {}; } 152namespace clang { namespace ento { 153template<> struct ProgramStateTrait<AllocatedData> 154 : public ProgramStatePartialTrait<AllocatedSetTy > { 155 static void *GDMIndex() { static int index = 0; return &index; } 156}; 157}} 158 159static bool isEnclosingFunctionParam(const Expr *E) { 160 E = E->IgnoreParenCasts(); 161 if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) { 162 const ValueDecl *VD = DRE->getDecl(); 163 if (isa<ImplicitParamDecl>(VD) || isa<ParmVarDecl>(VD)) 164 return true; 165 } 166 return false; 167} 168 169const MacOSKeychainAPIChecker::ADFunctionInfo 170 MacOSKeychainAPIChecker::FunctionsToTrack[FunctionsToTrackSize] = { 171 {"SecKeychainItemCopyContent", 4, 3, ValidAPI}, // 0 172 {"SecKeychainFindGenericPassword", 6, 3, ValidAPI}, // 1 173 {"SecKeychainFindInternetPassword", 13, 3, ValidAPI}, // 2 174 {"SecKeychainItemFreeContent", 1, InvalidIdx, ValidAPI}, // 3 175 {"SecKeychainItemCopyAttributesAndData", 5, 5, ValidAPI}, // 4 176 {"SecKeychainItemFreeAttributesAndData", 1, InvalidIdx, ValidAPI}, // 5 177 {"free", 0, InvalidIdx, ErrorAPI}, // 6 178 {"CFStringCreateWithBytesNoCopy", 1, InvalidIdx, PossibleAPI}, // 7 179}; 180 181unsigned MacOSKeychainAPIChecker::getTrackedFunctionIndex(StringRef Name, 182 bool IsAllocator) { 183 for (unsigned I = 0; I < FunctionsToTrackSize; ++I) { 184 ADFunctionInfo FI = FunctionsToTrack[I]; 185 if (FI.Name != Name) 186 continue; 187 // Make sure the function is of the right type (allocator vs deallocator). 188 if (IsAllocator && (FI.DeallocatorIdx == InvalidIdx)) 189 return InvalidIdx; 190 if (!IsAllocator && (FI.DeallocatorIdx != InvalidIdx)) 191 return InvalidIdx; 192 193 return I; 194 } 195 // The function is not tracked. 196 return InvalidIdx; 197} 198 199static SymbolRef getSymbolForRegion(CheckerContext &C, 200 const MemRegion *R) { 201 // Implicit casts (ex: void* -> char*) can turn Symbolic region into element 202 // region, if that is the case, get the underlining region. 203 R = R->StripCasts(); 204 if (!isa<SymbolicRegion>(R)) { 205 return 0; 206 } 207 return cast<SymbolicRegion>(R)->getSymbol(); 208} 209 210static bool isBadDeallocationArgument(const MemRegion *Arg) { 211 if (isa<AllocaRegion>(Arg) || 212 isa<BlockDataRegion>(Arg) || 213 isa<TypedRegion>(Arg)) { 214 return true; 215 } 216 return false; 217} 218/// Given the address expression, retrieve the value it's pointing to. Assume 219/// that value is itself an address, and return the corresponding symbol. 220static SymbolRef getAsPointeeSymbol(const Expr *Expr, 221 CheckerContext &C) { 222 const ProgramState *State = C.getState(); 223 SVal ArgV = State->getSVal(Expr, C.getLocationContext()); 224 225 if (const loc::MemRegionVal *X = dyn_cast<loc::MemRegionVal>(&ArgV)) { 226 StoreManager& SM = C.getStoreManager(); 227 const MemRegion *V = SM.getBinding(State->getStore(), *X).getAsRegion(); 228 if (V) 229 return getSymbolForRegion(C, V); 230 } 231 return 0; 232} 233 234// When checking for error code, we need to consider the following cases: 235// 1) noErr / [0] 236// 2) someErr / [1, inf] 237// 3) unknown 238// If noError, returns true iff (1). 239// If !noError, returns true iff (2). 240bool MacOSKeychainAPIChecker::definitelyReturnedError(SymbolRef RetSym, 241 const ProgramState *State, 242 SValBuilder &Builder, 243 bool noError) const { 244 DefinedOrUnknownSVal NoErrVal = Builder.makeIntVal(NoErr, 245 Builder.getSymbolManager().getType(RetSym)); 246 DefinedOrUnknownSVal NoErr = Builder.evalEQ(State, NoErrVal, 247 nonloc::SymbolVal(RetSym)); 248 const ProgramState *ErrState = State->assume(NoErr, noError); 249 if (ErrState == State) { 250 return true; 251 } 252 253 return false; 254} 255 256// Report deallocator mismatch. Remove the region from tracking - reporting a 257// missing free error after this one is redundant. 258void MacOSKeychainAPIChecker:: 259 generateDeallocatorMismatchReport(const AllocationPair &AP, 260 const Expr *ArgExpr, 261 CheckerContext &C) const { 262 const ProgramState *State = C.getState(); 263 State = State->remove<AllocatedData>(AP.first); 264 ExplodedNode *N = C.addTransition(State); 265 266 if (!N) 267 return; 268 initBugType(); 269 llvm::SmallString<80> sbuf; 270 llvm::raw_svector_ostream os(sbuf); 271 unsigned int PDeallocIdx = 272 FunctionsToTrack[AP.second->AllocatorIdx].DeallocatorIdx; 273 274 os << "Deallocator doesn't match the allocator: '" 275 << FunctionsToTrack[PDeallocIdx].Name << "' should be used."; 276 BugReport *Report = new BugReport(*BT, os.str(), N); 277 Report->addVisitor(new SecKeychainBugVisitor(AP.first)); 278 Report->addRange(ArgExpr->getSourceRange()); 279 C.EmitReport(Report); 280} 281 282void MacOSKeychainAPIChecker::checkPreStmt(const CallExpr *CE, 283 CheckerContext &C) const { 284 unsigned idx = InvalidIdx; 285 const ProgramState *State = C.getState(); 286 287 StringRef funName = C.getCalleeName(CE); 288 if (funName.empty()) 289 return; 290 291 // If it is a call to an allocator function, it could be a double allocation. 292 idx = getTrackedFunctionIndex(funName, true); 293 if (idx != InvalidIdx) { 294 const Expr *ArgExpr = CE->getArg(FunctionsToTrack[idx].Param); 295 if (SymbolRef V = getAsPointeeSymbol(ArgExpr, C)) 296 if (const AllocationState *AS = State->get<AllocatedData>(V)) { 297 if (!definitelyReturnedError(AS->Region, State, C.getSValBuilder())) { 298 // Remove the value from the state. The new symbol will be added for 299 // tracking when the second allocator is processed in checkPostStmt(). 300 State = State->remove<AllocatedData>(V); 301 ExplodedNode *N = C.addTransition(State); 302 if (!N) 303 return; 304 initBugType(); 305 llvm::SmallString<128> sbuf; 306 llvm::raw_svector_ostream os(sbuf); 307 unsigned int DIdx = FunctionsToTrack[AS->AllocatorIdx].DeallocatorIdx; 308 os << "Allocated data should be released before another call to " 309 << "the allocator: missing a call to '" 310 << FunctionsToTrack[DIdx].Name 311 << "'."; 312 BugReport *Report = new BugReport(*BT, os.str(), N); 313 Report->addVisitor(new SecKeychainBugVisitor(V)); 314 Report->addRange(ArgExpr->getSourceRange()); 315 C.EmitReport(Report); 316 } 317 } 318 return; 319 } 320 321 // Is it a call to one of deallocator functions? 322 idx = getTrackedFunctionIndex(funName, false); 323 if (idx == InvalidIdx) 324 return; 325 326 // Check the argument to the deallocator. 327 const Expr *ArgExpr = CE->getArg(FunctionsToTrack[idx].Param); 328 SVal ArgSVal = State->getSVal(ArgExpr, C.getLocationContext()); 329 330 // Undef is reported by another checker. 331 if (ArgSVal.isUndef()) 332 return; 333 334 const MemRegion *Arg = ArgSVal.getAsRegion(); 335 if (!Arg) 336 return; 337 338 SymbolRef ArgSM = getSymbolForRegion(C, Arg); 339 bool RegionArgIsBad = ArgSM ? false : isBadDeallocationArgument(Arg); 340 // If the argument is coming from the heap, globals, or unknown, do not 341 // report it. 342 if (!ArgSM && !RegionArgIsBad) 343 return; 344 345 // Is the argument to the call being tracked? 346 const AllocationState *AS = State->get<AllocatedData>(ArgSM); 347 if (!AS && FunctionsToTrack[idx].Kind != ValidAPI) { 348 return; 349 } 350 // If trying to free data which has not been allocated yet, report as a bug. 351 // TODO: We might want a more precise diagnostic for double free 352 // (that would involve tracking all the freed symbols in the checker state). 353 if (!AS || RegionArgIsBad) { 354 // It is possible that this is a false positive - the argument might 355 // have entered as an enclosing function parameter. 356 if (isEnclosingFunctionParam(ArgExpr)) 357 return; 358 359 ExplodedNode *N = C.addTransition(State); 360 if (!N) 361 return; 362 initBugType(); 363 BugReport *Report = new BugReport(*BT, 364 "Trying to free data which has not been allocated.", N); 365 Report->addRange(ArgExpr->getSourceRange()); 366 C.EmitReport(Report); 367 return; 368 } 369 370 // Process functions which might deallocate. 371 if (FunctionsToTrack[idx].Kind == PossibleAPI) { 372 373 if (funName == "CFStringCreateWithBytesNoCopy") { 374 const Expr *DeallocatorExpr = CE->getArg(5)->IgnoreParenCasts(); 375 // NULL ~ default deallocator, so warn. 376 if (DeallocatorExpr->isNullPointerConstant(C.getASTContext(), 377 Expr::NPC_ValueDependentIsNotNull)) { 378 const AllocationPair AP = std::make_pair(ArgSM, AS); 379 generateDeallocatorMismatchReport(AP, ArgExpr, C); 380 return; 381 } 382 // One of the default allocators, so warn. 383 if (const DeclRefExpr *DE = dyn_cast<DeclRefExpr>(DeallocatorExpr)) { 384 StringRef DeallocatorName = DE->getFoundDecl()->getName(); 385 if (DeallocatorName == "kCFAllocatorDefault" || 386 DeallocatorName == "kCFAllocatorSystemDefault" || 387 DeallocatorName == "kCFAllocatorMalloc") { 388 const AllocationPair AP = std::make_pair(ArgSM, AS); 389 generateDeallocatorMismatchReport(AP, ArgExpr, C); 390 return; 391 } 392 // If kCFAllocatorNull, which does not deallocate, we still have to 393 // find the deallocator. Otherwise, assume that the user had written a 394 // custom deallocator which does the right thing. 395 if (DE->getFoundDecl()->getName() != "kCFAllocatorNull") { 396 State = State->remove<AllocatedData>(ArgSM); 397 C.addTransition(State); 398 return; 399 } 400 } 401 } 402 return; 403 } 404 405 // The call is deallocating a value we previously allocated, so remove it 406 // from the next state. 407 State = State->remove<AllocatedData>(ArgSM); 408 409 // Check if the proper deallocator is used. 410 unsigned int PDeallocIdx = FunctionsToTrack[AS->AllocatorIdx].DeallocatorIdx; 411 if (PDeallocIdx != idx || (FunctionsToTrack[idx].Kind == ErrorAPI)) { 412 const AllocationPair AP = std::make_pair(ArgSM, AS); 413 generateDeallocatorMismatchReport(AP, ArgExpr, C); 414 return; 415 } 416 417 // If the buffer can be null and the return status can be an error, 418 // report a bad call to free. 419 if (State->assume(cast<DefinedSVal>(ArgSVal), false) && 420 !definitelyDidnotReturnError(AS->Region, State, C.getSValBuilder())) { 421 ExplodedNode *N = C.addTransition(State); 422 if (!N) 423 return; 424 initBugType(); 425 BugReport *Report = new BugReport(*BT, 426 "Only call free if a valid (non-NULL) buffer was returned.", N); 427 Report->addVisitor(new SecKeychainBugVisitor(ArgSM)); 428 Report->addRange(ArgExpr->getSourceRange()); 429 C.EmitReport(Report); 430 return; 431 } 432 433 C.addTransition(State); 434} 435 436void MacOSKeychainAPIChecker::checkPostStmt(const CallExpr *CE, 437 CheckerContext &C) const { 438 const ProgramState *State = C.getState(); 439 StringRef funName = C.getCalleeName(CE); 440 441 // If a value has been allocated, add it to the set for tracking. 442 unsigned idx = getTrackedFunctionIndex(funName, true); 443 if (idx == InvalidIdx) 444 return; 445 446 const Expr *ArgExpr = CE->getArg(FunctionsToTrack[idx].Param); 447 // If the argument entered as an enclosing function parameter, skip it to 448 // avoid false positives. 449 if (isEnclosingFunctionParam(ArgExpr)) 450 return; 451 452 if (SymbolRef V = getAsPointeeSymbol(ArgExpr, C)) { 453 // If the argument points to something that's not a symbolic region, it 454 // can be: 455 // - unknown (cannot reason about it) 456 // - undefined (already reported by other checker) 457 // - constant (null - should not be tracked, 458 // other constant will generate a compiler warning) 459 // - goto (should be reported by other checker) 460 461 // The call return value symbol should stay alive for as long as the 462 // allocated value symbol, since our diagnostics depend on the value 463 // returned by the call. Ex: Data should only be freed if noErr was 464 // returned during allocation.) 465 SymbolRef RetStatusSymbol = 466 State->getSVal(CE, C.getLocationContext()).getAsSymbol(); 467 C.getSymbolManager().addSymbolDependency(V, RetStatusSymbol); 468 469 // Track the allocated value in the checker state. 470 State = State->set<AllocatedData>(V, AllocationState(ArgExpr, idx, 471 RetStatusSymbol)); 472 assert(State); 473 C.addTransition(State); 474 } 475} 476 477void MacOSKeychainAPIChecker::checkPreStmt(const ReturnStmt *S, 478 CheckerContext &C) const { 479 const Expr *retExpr = S->getRetValue(); 480 if (!retExpr) 481 return; 482 483 // Check if the value is escaping through the return. 484 const ProgramState *state = C.getState(); 485 const MemRegion *V = 486 state->getSVal(retExpr, C.getLocationContext()).getAsRegion(); 487 if (!V) 488 return; 489 state = state->remove<AllocatedData>(getSymbolForRegion(C, V)); 490 491 // Proceed from the new state. 492 C.addTransition(state); 493} 494 495BugReport *MacOSKeychainAPIChecker:: 496 generateAllocatedDataNotReleasedReport(const AllocationPair &AP, 497 ExplodedNode *N) const { 498 const ADFunctionInfo &FI = FunctionsToTrack[AP.second->AllocatorIdx]; 499 initBugType(); 500 llvm::SmallString<70> sbuf; 501 llvm::raw_svector_ostream os(sbuf); 502 503 os << "Allocated data is not released: missing a call to '" 504 << FunctionsToTrack[FI.DeallocatorIdx].Name << "'."; 505 BugReport *Report = new BugReport(*BT, os.str(), N); 506 Report->addVisitor(new SecKeychainBugVisitor(AP.first)); 507 Report->addRange(SourceRange()); 508 return Report; 509} 510 511void MacOSKeychainAPIChecker::checkDeadSymbols(SymbolReaper &SR, 512 CheckerContext &C) const { 513 const ProgramState *State = C.getState(); 514 AllocatedSetTy ASet = State->get<AllocatedData>(); 515 if (ASet.isEmpty()) 516 return; 517 518 bool Changed = false; 519 AllocationPairVec Errors; 520 for (AllocatedSetTy::iterator I = ASet.begin(), E = ASet.end(); I != E; ++I) { 521 if (SR.isLive(I->first)) 522 continue; 523 524 Changed = true; 525 State = State->remove<AllocatedData>(I->first); 526 // If the allocated symbol is null or if the allocation call might have 527 // returned an error, do not report. 528 if (State->getSymVal(I->first) || 529 definitelyReturnedError(I->second.Region, State, C.getSValBuilder())) 530 continue; 531 Errors.push_back(std::make_pair(I->first, &I->second)); 532 } 533 if (!Changed) 534 return; 535 536 // Generate the new, cleaned up state. 537 ExplodedNode *N = C.addTransition(State); 538 if (!N) 539 return; 540 541 // Generate the error reports. 542 for (AllocationPairVec::iterator I = Errors.begin(), E = Errors.end(); 543 I != E; ++I) { 544 C.EmitReport(generateAllocatedDataNotReleasedReport(*I, N)); 545 } 546} 547 548// TODO: Remove this after we ensure that checkDeadSymbols are always called. 549void MacOSKeychainAPIChecker::checkEndPath(CheckerContext &Ctx) const { 550 const ProgramState *state = Ctx.getState(); 551 AllocatedSetTy AS = state->get<AllocatedData>(); 552 if (AS.isEmpty()) 553 return; 554 555 // Anything which has been allocated but not freed (nor escaped) will be 556 // found here, so report it. 557 bool Changed = false; 558 AllocationPairVec Errors; 559 for (AllocatedSetTy::iterator I = AS.begin(), E = AS.end(); I != E; ++I ) { 560 Changed = true; 561 state = state->remove<AllocatedData>(I->first); 562 // If the allocated symbol is null or if error code was returned at 563 // allocation, do not report. 564 if (state->getSymVal(I.getKey()) || 565 definitelyReturnedError(I->second.Region, state, 566 Ctx.getSValBuilder())) { 567 continue; 568 } 569 Errors.push_back(std::make_pair(I->first, &I->second)); 570 } 571 572 // If no change, do not generate a new state. 573 if (!Changed) 574 return; 575 576 ExplodedNode *N = Ctx.addTransition(state); 577 if (!N) 578 return; 579 580 // Generate the error reports. 581 for (AllocationPairVec::iterator I = Errors.begin(), E = Errors.end(); 582 I != E; ++I) { 583 Ctx.EmitReport(generateAllocatedDataNotReleasedReport(*I, N)); 584 } 585} 586 587 588PathDiagnosticPiece *MacOSKeychainAPIChecker::SecKeychainBugVisitor::VisitNode( 589 const ExplodedNode *N, 590 const ExplodedNode *PrevN, 591 BugReporterContext &BRC, 592 BugReport &BR) { 593 const AllocationState *AS = N->getState()->get<AllocatedData>(Sym); 594 if (!AS) 595 return 0; 596 const AllocationState *ASPrev = PrevN->getState()->get<AllocatedData>(Sym); 597 if (ASPrev) 598 return 0; 599 600 // (!ASPrev && AS) ~ We started tracking symbol in node N, it must be the 601 // allocation site. 602 const CallExpr *CE = cast<CallExpr>(cast<StmtPoint>(N->getLocation()) 603 .getStmt()); 604 const FunctionDecl *funDecl = CE->getDirectCallee(); 605 assert(funDecl && "We do not support indirect function calls as of now."); 606 StringRef funName = funDecl->getName(); 607 608 // Get the expression of the corresponding argument. 609 unsigned Idx = getTrackedFunctionIndex(funName, true); 610 assert(Idx != InvalidIdx && "This should be a call to an allocator."); 611 const Expr *ArgExpr = CE->getArg(FunctionsToTrack[Idx].Param); 612 PathDiagnosticLocation Pos(ArgExpr, BRC.getSourceManager(), 613 N->getLocationContext()); 614 return new PathDiagnosticEventPiece(Pos, "Data is allocated here."); 615} 616 617void ento::registerMacOSKeychainAPIChecker(CheckerManager &mgr) { 618 mgr.registerChecker<MacOSKeychainAPIChecker>(); 619} 620