maxjhandsome
/
llvm-project
forked from OSchip/llvm-project
1
0
Fork 0
Code Issues Pull Requests Packages Releases Wiki Activity
llvm-project/clang/lib/Analysis/BasicObjCFoundationChecks.cpp

583 lines
16 KiB
C++
Raw Blame History

//== BasicObjCFoundationChecks.cpp - Simple Apple-Foundation checks -*- C++ -*--
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines BasicObjCFoundationChecks, a class that encapsulates
// a set of simple checks to run on Objective-C code using Apple's Foundation
// classes.
//
//===----------------------------------------------------------------------===//
#include "BasicObjCFoundationChecks.h"
#include "clang/Analysis/PathSensitive/ExplodedGraph.h"
#include "clang/Analysis/PathSensitive/GRSimpleAPICheck.h"
#include "clang/Analysis/PathSensitive/GRExprEngine.h"
#include "clang/Analysis/PathSensitive/GRState.h"
#include "clang/Analysis/PathSensitive/BugReporter.h"
#include "clang/Analysis/PathSensitive/MemRegion.h"
#include "clang/Analysis/PathDiagnostic.h"
#include "clang/Analysis/LocalCheckers.h"
#include "clang/AST/DeclObjC.h"
#include "clang/AST/Expr.h"
#include "clang/AST/ExprObjC.h"
#include "clang/AST/ASTContext.h"
#include "llvm/Support/Compiler.h"
#include <sstream>
using namespace clang;
static ObjCInterfaceType* GetReceiverType(ObjCMessageExpr* ME) {
Expr* Receiver = ME->getReceiver();
if (!Receiver)
return NULL;
QualType X = Receiver->getType();
if (X->isPointerType()) {
Type* TP = X.getTypePtr();
const PointerType* T = TP->getAsPointerType();
return dyn_cast<ObjCInterfaceType>(T->getPointeeType().getTypePtr());
}
// FIXME: Support ObjCQualifiedIdType?
return NULL;
}
static const char* GetReceiverNameType(ObjCMessageExpr* ME) {
ObjCInterfaceType* ReceiverType = GetReceiverType(ME);
return ReceiverType ? ReceiverType->getDecl()->getIdentifier()->getName()
: NULL;
}
namespace {
class VISIBILITY_HIDDEN APIMisuse : public BugTypeCacheLocation {
public:
const char* getCategory() const {
return "API Misuse (Apple)";
}
};
class VISIBILITY_HIDDEN NilArg : public APIMisuse {
public:
virtual ~NilArg() {}
virtual const char* getName() const {
return "nil argument";
}
class Report : public BugReport {
std::string Msg;
const char* s;
SourceRange R;
public:
Report(NilArg& Desc, ExplodedNode<GRState>* N,
ObjCMessageExpr* ME, unsigned Arg)
: BugReport(Desc, N) {
Expr* E = ME->getArg(Arg);
R = E->getSourceRange();
std::ostringstream os;
os << "Argument to '" << GetReceiverNameType(ME) << "' method '"
<< ME->getSelector().getAsString() << "' cannot be nil.";
Msg = os.str();
s = Msg.c_str();
}
virtual ~Report() {}
virtual const char* getDescription() const { return s; }
virtual void getRanges(BugReporter& BR,
const SourceRange*& B, const SourceRange*& E) {
B = &R;
E = B+1;
}
};
};
class VISIBILITY_HIDDEN BasicObjCFoundationChecks : public GRSimpleAPICheck {
NilArg Desc;
ASTContext &Ctx;
GRStateManager* VMgr;
typedef std::vector<BugReport*> ErrorsTy;
ErrorsTy Errors;
SVal GetSVal(const GRState* St, Expr* E) { return VMgr->GetSVal(St, E); }
bool isNSString(ObjCInterfaceType* T, const char* suffix);
bool AuditNSString(NodeTy* N, ObjCMessageExpr* ME);
void Warn(NodeTy* N, Expr* E, const std::string& s);
void WarnNilArg(NodeTy* N, Expr* E);
bool CheckNilArg(NodeTy* N, unsigned Arg);
public:
BasicObjCFoundationChecks(ASTContext& ctx, GRStateManager* vmgr)
: Ctx(ctx), VMgr(vmgr) {}
virtual ~BasicObjCFoundationChecks() {
for (ErrorsTy::iterator I = Errors.begin(), E = Errors.end(); I!=E; ++I)
delete *I;
}
virtual bool Audit(ExplodedNode<GRState>* N, GRStateManager&);
virtual void EmitWarnings(BugReporter& BR);
private:
void AddError(BugReport* R) {
Errors.push_back(R);
}
void WarnNilArg(NodeTy* N, ObjCMessageExpr* ME, unsigned Arg) {
AddError(new NilArg::Report(Desc, N, ME, Arg));
}
};
} // end anonymous namespace
GRSimpleAPICheck*
clang::CreateBasicObjCFoundationChecks(ASTContext& Ctx,
GRStateManager* VMgr) {
return new BasicObjCFoundationChecks(Ctx, VMgr);
}
bool BasicObjCFoundationChecks::Audit(ExplodedNode<GRState>* N,
GRStateManager&) {
ObjCMessageExpr* ME =
cast<ObjCMessageExpr>(cast<PostStmt>(N->getLocation()).getStmt());
ObjCInterfaceType* ReceiverType = GetReceiverType(ME);
if (!ReceiverType)
return false;
const char* name = ReceiverType->getDecl()->getIdentifier()->getName();
if (!name)
return false;
if (name[0] != 'N' || name[1] != 'S')
return false;
name += 2;
// FIXME: Make all of this faster.
if (isNSString(ReceiverType, name))
return AuditNSString(N, ME);
return false;
}
static inline bool isNil(SVal X) {
return isa<loc::ConcreteInt>(X);
}
//===----------------------------------------------------------------------===//
// Error reporting.
//===----------------------------------------------------------------------===//
void BasicObjCFoundationChecks::EmitWarnings(BugReporter& BR) {
for (ErrorsTy::iterator I=Errors.begin(), E=Errors.end(); I!=E; ++I)
BR.EmitWarning(**I);
}
bool BasicObjCFoundationChecks::CheckNilArg(NodeTy* N, unsigned Arg) {
ObjCMessageExpr* ME =
cast<ObjCMessageExpr>(cast<PostStmt>(N->getLocation()).getStmt());
Expr * E = ME->getArg(Arg);
if (isNil(GetSVal(N->getState(), E))) {
WarnNilArg(N, ME, Arg);
return true;
}
return false;
}
//===----------------------------------------------------------------------===//
// NSString checking.
//===----------------------------------------------------------------------===//
bool BasicObjCFoundationChecks::isNSString(ObjCInterfaceType* T,
const char* suffix) {
return !strcmp("String", suffix) || !strcmp("MutableString", suffix);
}
bool BasicObjCFoundationChecks::AuditNSString(NodeTy* N,
ObjCMessageExpr* ME) {
Selector S = ME->getSelector();
if (S.isUnarySelector())
return false;
// FIXME: This is going to be really slow doing these checks with
// lexical comparisons.
std::string name = S.getAsString();
assert (!name.empty());
const char* cstr = &name[0];
unsigned len = name.size();
switch (len) {
default:
break;
case 8:
if (!strcmp(cstr, "compare:"))
return CheckNilArg(N, 0);
break;
case 15:
// FIXME: Checking for initWithFormat: will not work in most cases
// yet because [NSString alloc] returns id, not NSString*. We will
// need support for tracking expected-type information in the analyzer
// to find these errors.
if (!strcmp(cstr, "initWithFormat:"))
return CheckNilArg(N, 0);
break;
case 16:
if (!strcmp(cstr, "compare:options:"))
return CheckNilArg(N, 0);
break;
case 22:
if (!strcmp(cstr, "compare:options:range:"))
return CheckNilArg(N, 0);
break;
case 23:
if (!strcmp(cstr, "caseInsensitiveCompare:"))
return CheckNilArg(N, 0);
break;
case 29:
if (!strcmp(cstr, "compare:options:range:locale:"))
return CheckNilArg(N, 0);
break;
case 37:
if (!strcmp(cstr, "componentsSeparatedByCharactersInSet:"))
return CheckNilArg(N, 0);
break;
}
return false;
}
//===----------------------------------------------------------------------===//
// Error reporting.
//===----------------------------------------------------------------------===//
namespace {
class VISIBILITY_HIDDEN BadCFNumberCreate : public APIMisuse{
public:
typedef std::vector<BugReport*> AllErrorsTy;
AllErrorsTy AllErrors;
virtual const char* getName() const {
return "Bad use of CFNumberCreate";
}
virtual void EmitWarnings(BugReporter& BR) {
// FIXME: Refactor this method.
for (AllErrorsTy::iterator I=AllErrors.begin(), E=AllErrors.end(); I!=E;++I)
BR.EmitWarning(**I);
}
};
// FIXME: This entire class should be refactored into the common
// BugReporter classes.
class VISIBILITY_HIDDEN StrBugReport : public RangedBugReport {
std::string str;
const char* cstr;
public:
StrBugReport(BugType& D, ExplodedNode<GRState>* N, std::string s)
: RangedBugReport(D, N), str(s) {
cstr = str.c_str();
}
virtual const char* getDescription() const { return cstr; }
};
class VISIBILITY_HIDDEN AuditCFNumberCreate : public GRSimpleAPICheck {
// FIXME: Who should own this?
BadCFNumberCreate Desc;
// FIXME: Either this should be refactored into GRSimpleAPICheck, or
// it should always be passed with a call to Audit. The latter
// approach makes this class more stateless.
ASTContext& Ctx;
IdentifierInfo* II;
GRStateManager* VMgr;
SVal GetSVal(const GRState* St, Expr* E) { return VMgr->GetSVal(St, E); }
public:
AuditCFNumberCreate(ASTContext& ctx, GRStateManager* vmgr)
: Ctx(ctx), II(&Ctx.Idents.get("CFNumberCreate")), VMgr(vmgr) {}
virtual ~AuditCFNumberCreate() {}
virtual bool Audit(ExplodedNode<GRState>* N, GRStateManager&);
virtual void EmitWarnings(BugReporter& BR) {
Desc.EmitWarnings(BR);
}
private:
void AddError(const TypedRegion* R, Expr* Ex, ExplodedNode<GRState> *N,
uint64_t SourceSize, uint64_t TargetSize, uint64_t NumberKind);
};
} // end anonymous namespace
enum CFNumberType {
kCFNumberSInt8Type = 1,
kCFNumberSInt16Type = 2,
kCFNumberSInt32Type = 3,
kCFNumberSInt64Type = 4,
kCFNumberFloat32Type = 5,
kCFNumberFloat64Type = 6,
kCFNumberCharType = 7,
kCFNumberShortType = 8,
kCFNumberIntType = 9,
kCFNumberLongType = 10,
kCFNumberLongLongType = 11,
kCFNumberFloatType = 12,
kCFNumberDoubleType = 13,
kCFNumberCFIndexType = 14,
kCFNumberNSIntegerType = 15,
kCFNumberCGFloatType = 16
};
namespace {
template<typename T>
class Optional {
bool IsKnown;
T Val;
public:
Optional() : IsKnown(false), Val(0) {}
Optional(const T& val) : IsKnown(true), Val(val) {}
bool isKnown() const { return IsKnown; }
const T& getValue() const {
assert (isKnown());
return Val;
}
operator const T&() const {
return getValue();
}
};
}
static Optional<uint64_t> GetCFNumberSize(ASTContext& Ctx, uint64_t i) {
static unsigned char FixedSize[] = { 8, 16, 32, 64, 32, 64 };
if (i < kCFNumberCharType)
return FixedSize[i-1];
QualType T;
switch (i) {
case kCFNumberCharType: T = Ctx.CharTy; break;
case kCFNumberShortType: T = Ctx.ShortTy; break;
case kCFNumberIntType: T = Ctx.IntTy; break;
case kCFNumberLongType: T = Ctx.LongTy; break;
case kCFNumberLongLongType: T = Ctx.LongLongTy; break;
case kCFNumberFloatType: T = Ctx.FloatTy; break;
case kCFNumberDoubleType: T = Ctx.DoubleTy; break;
case kCFNumberCFIndexType:
case kCFNumberNSIntegerType:
case kCFNumberCGFloatType:
// FIXME: We need a way to map from names to Type*.
default:
return Optional<uint64_t>();
}
return Ctx.getTypeSize(T);
}
#if 0
static const char* GetCFNumberTypeStr(uint64_t i) {
static const char* Names[] = {
"kCFNumberSInt8Type",
"kCFNumberSInt16Type",
"kCFNumberSInt32Type",
"kCFNumberSInt64Type",
"kCFNumberFloat32Type",
"kCFNumberFloat64Type",
"kCFNumberCharType",
"kCFNumberShortType",
"kCFNumberIntType",
"kCFNumberLongType",
"kCFNumberLongLongType",
"kCFNumberFloatType",
"kCFNumberDoubleType",
"kCFNumberCFIndexType",
"kCFNumberNSIntegerType",
"kCFNumberCGFloatType"
};
return i <= kCFNumberCGFloatType ? Names[i-1] : "Invalid CFNumberType";
}
#endif
bool AuditCFNumberCreate::Audit(ExplodedNode<GRState>* N,GRStateManager&){
CallExpr* CE = cast<CallExpr>(cast<PostStmt>(N->getLocation()).getStmt());
Expr* Callee = CE->getCallee();
SVal CallV = GetSVal(N->getState(), Callee);
loc::FuncVal* FuncV = dyn_cast<loc::FuncVal>(&CallV);
if (!FuncV || FuncV->getDecl()->getIdentifier() != II || CE->getNumArgs()!=3)
return false;
// Get the value of the "theType" argument.
SVal TheTypeVal = GetSVal(N->getState(), CE->getArg(1));
// FIXME: We really should allow ranges of valid theType values, and
// bifurcate the state appropriately.
nonloc::ConcreteInt* V = dyn_cast<nonloc::ConcreteInt>(&TheTypeVal);
if (!V)
return false;
uint64_t NumberKind = V->getValue().getLimitedValue();
Optional<uint64_t> TargetSize = GetCFNumberSize(Ctx, NumberKind);
// FIXME: In some cases we can emit an error.
if (!TargetSize.isKnown())
return false;
// Look at the value of the integer being passed by reference. Essentially
// we want to catch cases where the value passed in is not equal to the
// size of the type being created.
SVal TheValueExpr = GetSVal(N->getState(), CE->getArg(2));
// FIXME: Eventually we should handle arbitrary locations. We can do this
// by having an enhanced memory model that does low-level typing.
loc::MemRegionVal* LV = dyn_cast<loc::MemRegionVal>(&TheValueExpr);
if (!LV)
return false;
const TypedRegion* R = dyn_cast<TypedRegion>(LV->getRegion());
if (!R) return false;
while (const AnonTypedRegion* ATR = dyn_cast<AnonTypedRegion>(R)) {
R = dyn_cast<TypedRegion>(ATR->getSuperRegion());
if (!R) return false;
}
QualType T = Ctx.getCanonicalType(R->getRValueType(Ctx));
// FIXME: If the pointee isn't an integer type, should we flag a warning?
// People can do weird stuff with pointers.
if (!T->isIntegerType())
return false;
uint64_t SourceSize = Ctx.getTypeSize(T);
// CHECK: is SourceSize == TargetSize
if (SourceSize == TargetSize)
return false;
AddError(R, CE->getArg(2), N, SourceSize, TargetSize, NumberKind);
// FIXME: We can actually create an abstract "CFNumber" object that has
// the bits initialized to the provided values.
return SourceSize < TargetSize;
}
void AuditCFNumberCreate::AddError(const TypedRegion* R, Expr* Ex,
ExplodedNode<GRState> *N,
uint64_t SourceSize, uint64_t TargetSize,
uint64_t NumberKind) {
std::ostringstream os;
os << (SourceSize == 8 ? "An " : "A ")
<< SourceSize << " bit integer is used to initialize a CFNumber "
"object that represents "
<< (TargetSize == 8 ? "an " : "a ")
<< TargetSize << " bit integer. ";
if (SourceSize < TargetSize)
os << (TargetSize - SourceSize)
<< " bits of the CFNumber value will be garbage." ;
else
os << (SourceSize - TargetSize)
<< " bits of the input integer will be lost.";
StrBugReport* B = new StrBugReport(Desc, N, os.str());
B->addRange(Ex->getSourceRange());
Desc.AllErrors.push_back(B);
}
GRSimpleAPICheck*
clang::CreateAuditCFNumberCreate(ASTContext& Ctx,
GRStateManager* VMgr) {
return new AuditCFNumberCreate(Ctx, VMgr);
}
//===----------------------------------------------------------------------===//
// Check registration.
void clang::RegisterAppleChecks(GRExprEngine& Eng) {
ASTContext& Ctx = Eng.getContext();
GRStateManager* VMgr = &Eng.getStateManager();
Eng.AddCheck(CreateBasicObjCFoundationChecks(Ctx, VMgr),
Stmt::ObjCMessageExprClass);
Eng.AddCheck(CreateAuditCFNumberCreate(Ctx, VMgr),
Stmt::CallExprClass);
Eng.Register(CreateNSErrorCheck());
}
Reference in New Issue View Git Blame Copy Permalink