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diff --git a/contrib/llvm/tools/clang/lib/Checker/CheckSecuritySyntaxOnly.cpp b/contrib/llvm/tools/clang/lib/Checker/CheckSecuritySyntaxOnly.cpp
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-//==- CheckSecuritySyntaxOnly.cpp - Basic security 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 a set of flow-insensitive security checks.
-//
-//===----------------------------------------------------------------------===//
-
-#include "clang/Basic/TargetInfo.h"
-#include "clang/Checker/BugReporter/BugReporter.h"
-#include "clang/Checker/Checkers/LocalCheckers.h"
-#include "clang/AST/StmtVisitor.h"
-#include "llvm/Support/raw_ostream.h"
-
-using namespace clang;
-
-static bool isArc4RandomAvailable(const ASTContext &Ctx) {
- const llvm::Triple &T = Ctx.Target.getTriple();
- return T.getVendor() == llvm::Triple::Apple ||
- T.getOS() == llvm::Triple::FreeBSD;
-}
-
-namespace {
-class WalkAST : public StmtVisitor<WalkAST> {
- BugReporter &BR;
- IdentifierInfo *II_gets;
- IdentifierInfo *II_getpw;
- IdentifierInfo *II_mktemp;
- enum { num_rands = 9 };
- IdentifierInfo *II_rand[num_rands];
- IdentifierInfo *II_random;
- enum { num_setids = 6 };
- IdentifierInfo *II_setid[num_setids];
-
- const bool CheckRand;
-
-public:
- WalkAST(BugReporter &br) : BR(br),
- II_gets(0), II_getpw(0), II_mktemp(0),
- II_rand(), II_random(0), II_setid(),
- CheckRand(isArc4RandomAvailable(BR.getContext())) {}
-
- // Statement visitor methods.
- void VisitCallExpr(CallExpr *CE);
- void VisitForStmt(ForStmt *S);
- void VisitCompoundStmt (CompoundStmt *S);
- void VisitStmt(Stmt *S) { VisitChildren(S); }
-
- void VisitChildren(Stmt *S);
-
- // Helpers.
- IdentifierInfo *GetIdentifier(IdentifierInfo *& II, const char *str);
-
- // Checker-specific methods.
- void CheckLoopConditionForFloat(const ForStmt *FS);
- void CheckCall_gets(const CallExpr *CE, const FunctionDecl *FD);
- void CheckCall_getpw(const CallExpr *CE, const FunctionDecl *FD);
- void CheckCall_mktemp(const CallExpr *CE, const FunctionDecl *FD);
- void CheckCall_rand(const CallExpr *CE, const FunctionDecl *FD);
- void CheckCall_random(const CallExpr *CE, const FunctionDecl *FD);
- void CheckUncheckedReturnValue(CallExpr *CE);
-};
-} // end anonymous namespace
-
-//===----------------------------------------------------------------------===//
-// Helper methods.
-//===----------------------------------------------------------------------===//
-
-IdentifierInfo *WalkAST::GetIdentifier(IdentifierInfo *& II, const char *str) {
- if (!II)
- II = &BR.getContext().Idents.get(str);
-
- return II;
-}
-
-//===----------------------------------------------------------------------===//
-// AST walking.
-//===----------------------------------------------------------------------===//
-
-void WalkAST::VisitChildren(Stmt *S) {
- for (Stmt::child_iterator I = S->child_begin(), E = S->child_end(); I!=E; ++I)
- if (Stmt *child = *I)
- Visit(child);
-}
-
-void WalkAST::VisitCallExpr(CallExpr *CE) {
- if (const FunctionDecl *FD = CE->getDirectCallee()) {
- CheckCall_gets(CE, FD);
- CheckCall_getpw(CE, FD);
- CheckCall_mktemp(CE, FD);
- if (CheckRand) {
- CheckCall_rand(CE, FD);
- CheckCall_random(CE, FD);
- }
- }
-
- // Recurse and check children.
- VisitChildren(CE);
-}
-
-void WalkAST::VisitCompoundStmt(CompoundStmt *S) {
- for (Stmt::child_iterator I = S->child_begin(), E = S->child_end(); I!=E; ++I)
- if (Stmt *child = *I) {
- if (CallExpr *CE = dyn_cast<CallExpr>(child))
- CheckUncheckedReturnValue(CE);
- Visit(child);
- }
-}
-
-void WalkAST::VisitForStmt(ForStmt *FS) {
- CheckLoopConditionForFloat(FS);
-
- // Recurse and check children.
- VisitChildren(FS);
-}
-
-//===----------------------------------------------------------------------===//
-// Check: floating poing variable used as loop counter.
-// Originally: <rdar://problem/6336718>
-// Implements: CERT security coding advisory FLP-30.
-//===----------------------------------------------------------------------===//
-
-static const DeclRefExpr*
-GetIncrementedVar(const Expr *expr, const VarDecl *x, const VarDecl *y) {
- expr = expr->IgnoreParenCasts();
-
- if (const BinaryOperator *B = dyn_cast<BinaryOperator>(expr)) {
- if (!(B->isAssignmentOp() || B->isCompoundAssignmentOp() ||
- B->getOpcode() == BO_Comma))
- return NULL;
-
- if (const DeclRefExpr *lhs = GetIncrementedVar(B->getLHS(), x, y))
- return lhs;
-
- if (const DeclRefExpr *rhs = GetIncrementedVar(B->getRHS(), x, y))
- return rhs;
-
- return NULL;
- }
-
- if (const DeclRefExpr *DR = dyn_cast<DeclRefExpr>(expr)) {
- const NamedDecl *ND = DR->getDecl();
- return ND == x || ND == y ? DR : NULL;
- }
-
- if (const UnaryOperator *U = dyn_cast<UnaryOperator>(expr))
- return U->isIncrementDecrementOp()
- ? GetIncrementedVar(U->getSubExpr(), x, y) : NULL;
-
- return NULL;
-}
-
-/// CheckLoopConditionForFloat - This check looks for 'for' statements that
-/// use a floating point variable as a loop counter.
-/// CERT: FLP30-C, FLP30-CPP.
-///
-void WalkAST::CheckLoopConditionForFloat(const ForStmt *FS) {
- // Does the loop have a condition?
- const Expr *condition = FS->getCond();
-
- if (!condition)
- return;
-
- // Does the loop have an increment?
- const Expr *increment = FS->getInc();
-
- if (!increment)
- return;
-
- // Strip away '()' and casts.
- condition = condition->IgnoreParenCasts();
- increment = increment->IgnoreParenCasts();
-
- // Is the loop condition a comparison?
- const BinaryOperator *B = dyn_cast<BinaryOperator>(condition);
-
- if (!B)
- return;
-
- // Is this a comparison?
- if (!(B->isRelationalOp() || B->isEqualityOp()))
- return;
-
- // Are we comparing variables?
- const DeclRefExpr *drLHS = dyn_cast<DeclRefExpr>(B->getLHS()->IgnoreParens());
- const DeclRefExpr *drRHS = dyn_cast<DeclRefExpr>(B->getRHS()->IgnoreParens());
-
- // Does at least one of the variables have a floating point type?
- drLHS = drLHS && drLHS->getType()->isRealFloatingType() ? drLHS : NULL;
- drRHS = drRHS && drRHS->getType()->isRealFloatingType() ? drRHS : NULL;
-
- if (!drLHS && !drRHS)
- return;
-
- const VarDecl *vdLHS = drLHS ? dyn_cast<VarDecl>(drLHS->getDecl()) : NULL;
- const VarDecl *vdRHS = drRHS ? dyn_cast<VarDecl>(drRHS->getDecl()) : NULL;
-
- if (!vdLHS && !vdRHS)
- return;
-
- // Does either variable appear in increment?
- const DeclRefExpr *drInc = GetIncrementedVar(increment, vdLHS, vdRHS);
-
- if (!drInc)
- return;
-
- // Emit the error. First figure out which DeclRefExpr in the condition
- // referenced the compared variable.
- const DeclRefExpr *drCond = vdLHS == drInc->getDecl() ? drLHS : drRHS;
-
- llvm::SmallVector<SourceRange, 2> ranges;
- llvm::SmallString<256> sbuf;
- llvm::raw_svector_ostream os(sbuf);
-
- os << "Variable '" << drCond->getDecl()->getName()
- << "' with floating point type '" << drCond->getType().getAsString()
- << "' should not be used as a loop counter";
-
- ranges.push_back(drCond->getSourceRange());
- ranges.push_back(drInc->getSourceRange());
-
- const char *bugType = "Floating point variable used as loop counter";
- BR.EmitBasicReport(bugType, "Security", os.str(),
- FS->getLocStart(), ranges.data(), ranges.size());
-}
-
-//===----------------------------------------------------------------------===//
-// Check: Any use of 'gets' is insecure.
-// Originally: <rdar://problem/6335715>
-// Implements (part of): 300-BSI (buildsecurityin.us-cert.gov)
-// CWE-242: Use of Inherently Dangerous Function
-//===----------------------------------------------------------------------===//
-
-void WalkAST::CheckCall_gets(const CallExpr *CE, const FunctionDecl *FD) {
- if (FD->getIdentifier() != GetIdentifier(II_gets, "gets"))
- return;
-
- const FunctionProtoType *FPT = dyn_cast<FunctionProtoType>(FD->getType());
- if (!FPT)
- return;
-
- // Verify that the function takes a single argument.
- if (FPT->getNumArgs() != 1)
- return;
-
- // Is the argument a 'char*'?
- const PointerType *PT = dyn_cast<PointerType>(FPT->getArgType(0));
- if (!PT)
- return;
-
- if (PT->getPointeeType().getUnqualifiedType() != BR.getContext().CharTy)
- return;
-
- // Issue a warning.
- SourceRange R = CE->getCallee()->getSourceRange();
- BR.EmitBasicReport("Potential buffer overflow in call to 'gets'",
- "Security",
- "Call to function 'gets' is extremely insecure as it can "
- "always result in a buffer overflow",
- CE->getLocStart(), &R, 1);
-}
-
-//===----------------------------------------------------------------------===//
-// Check: Any use of 'getpwd' is insecure.
-// CWE-477: Use of Obsolete Functions
-//===----------------------------------------------------------------------===//
-
-void WalkAST::CheckCall_getpw(const CallExpr *CE, const FunctionDecl *FD) {
- if (FD->getIdentifier() != GetIdentifier(II_getpw, "getpw"))
- return;
-
- const FunctionProtoType *FPT = dyn_cast<FunctionProtoType>(FD->getType());
- if (!FPT)
- return;
-
- // Verify that the function takes two arguments.
- if (FPT->getNumArgs() != 2)
- return;
-
- // Verify the first argument type is integer.
- if (!FPT->getArgType(0)->isIntegerType())
- return;
-
- // Verify the second argument type is char*.
- const PointerType *PT = dyn_cast<PointerType>(FPT->getArgType(1));
- if (!PT)
- return;
-
- if (PT->getPointeeType().getUnqualifiedType() != BR.getContext().CharTy)
- return;
-
- // Issue a warning.
- SourceRange R = CE->getCallee()->getSourceRange();
- BR.EmitBasicReport("Potential buffer overflow in call to 'getpw'",
- "Security",
- "The getpw() function is dangerous as it may overflow the "
- "provided buffer. It is obsoleted by getpwuid().",
- CE->getLocStart(), &R, 1);
-}
-
-//===----------------------------------------------------------------------===//
-// Check: Any use of 'mktemp' is insecure.It is obsoleted by mkstemp().
-// CWE-377: Insecure Temporary File
-//===----------------------------------------------------------------------===//
-
-void WalkAST::CheckCall_mktemp(const CallExpr *CE, const FunctionDecl *FD) {
- if (FD->getIdentifier() != GetIdentifier(II_mktemp, "mktemp"))
- return;
-
- const FunctionProtoType *FPT = dyn_cast<FunctionProtoType>(FD->getType());
- if(!FPT)
- return;
-
- // Verify that the funcion takes a single argument.
- if (FPT->getNumArgs() != 1)
- return;
-
- // Verify that the argument is Pointer Type.
- const PointerType *PT = dyn_cast<PointerType>(FPT->getArgType(0));
- if (!PT)
- return;
-
- // Verify that the argument is a 'char*'.
- if (PT->getPointeeType().getUnqualifiedType() != BR.getContext().CharTy)
- return;
-
- // Issue a waring.
- SourceRange R = CE->getCallee()->getSourceRange();
- BR.EmitBasicReport("Potential insecure temporary file in call 'mktemp'",
- "Security",
- "Call to function 'mktemp' is insecure as it always "
- "creates or uses insecure temporary file. Use 'mkstemp' instead",
- CE->getLocStart(), &R, 1);
-}
-
-//===----------------------------------------------------------------------===//
-// Check: Linear congruent random number generators should not be used
-// Originally: <rdar://problem/63371000>
-// CWE-338: Use of cryptographically weak prng
-//===----------------------------------------------------------------------===//
-
-void WalkAST::CheckCall_rand(const CallExpr *CE, const FunctionDecl *FD) {
- if (II_rand[0] == NULL) {
- // This check applies to these functions
- static const char * const identifiers[num_rands] = {
- "drand48", "erand48", "jrand48", "lrand48", "mrand48", "nrand48",
- "lcong48",
- "rand", "rand_r"
- };
-
- for (size_t i = 0; i < num_rands; i++)
- II_rand[i] = &BR.getContext().Idents.get(identifiers[i]);
- }
-
- const IdentifierInfo *id = FD->getIdentifier();
- size_t identifierid;
-
- for (identifierid = 0; identifierid < num_rands; identifierid++)
- if (id == II_rand[identifierid])
- break;
-
- if (identifierid >= num_rands)
- return;
-
- const FunctionProtoType *FTP = dyn_cast<FunctionProtoType>(FD->getType());
- if (!FTP)
- return;
-
- if (FTP->getNumArgs() == 1) {
- // Is the argument an 'unsigned short *'?
- // (Actually any integer type is allowed.)
- const PointerType *PT = dyn_cast<PointerType>(FTP->getArgType(0));
- if (!PT)
- return;
-
- if (! PT->getPointeeType()->isIntegerType())
- return;
- }
- else if (FTP->getNumArgs() != 0)
- return;
-
- // Issue a warning.
- llvm::SmallString<256> buf1;
- llvm::raw_svector_ostream os1(buf1);
- os1 << '\'' << FD << "' is a poor random number generator";
-
- llvm::SmallString<256> buf2;
- llvm::raw_svector_ostream os2(buf2);
- os2 << "Function '" << FD
- << "' is obsolete because it implements a poor random number generator."
- << " Use 'arc4random' instead";
-
- SourceRange R = CE->getCallee()->getSourceRange();
- BR.EmitBasicReport(os1.str(), "Security", os2.str(),CE->getLocStart(), &R, 1);
-}
-
-//===----------------------------------------------------------------------===//
-// Check: 'random' should not be used
-// Originally: <rdar://problem/63371000>
-//===----------------------------------------------------------------------===//
-
-void WalkAST::CheckCall_random(const CallExpr *CE, const FunctionDecl *FD) {
- if (FD->getIdentifier() != GetIdentifier(II_random, "random"))
- return;
-
- const FunctionProtoType *FTP = dyn_cast<FunctionProtoType>(FD->getType());
- if (!FTP)
- return;
-
- // Verify that the function takes no argument.
- if (FTP->getNumArgs() != 0)
- return;
-
- // Issue a warning.
- SourceRange R = CE->getCallee()->getSourceRange();
- BR.EmitBasicReport("'random' is not a secure random number generator",
- "Security",
- "The 'random' function produces a sequence of values that "
- "an adversary may be able to predict. Use 'arc4random' "
- "instead", CE->getLocStart(), &R, 1);
-}
-
-//===----------------------------------------------------------------------===//
-// Check: Should check whether privileges are dropped successfully.
-// Originally: <rdar://problem/6337132>
-//===----------------------------------------------------------------------===//
-
-void WalkAST::CheckUncheckedReturnValue(CallExpr *CE) {
- const FunctionDecl *FD = CE->getDirectCallee();
- if (!FD)
- return;
-
- if (II_setid[0] == NULL) {
- static const char * const identifiers[num_setids] = {
- "setuid", "setgid", "seteuid", "setegid",
- "setreuid", "setregid"
- };
-
- for (size_t i = 0; i < num_setids; i++)
- II_setid[i] = &BR.getContext().Idents.get(identifiers[i]);
- }
-
- const IdentifierInfo *id = FD->getIdentifier();
- size_t identifierid;
-
- for (identifierid = 0; identifierid < num_setids; identifierid++)
- if (id == II_setid[identifierid])
- break;
-
- if (identifierid >= num_setids)
- return;
-
- const FunctionProtoType *FTP = dyn_cast<FunctionProtoType>(FD->getType());
- if (!FTP)
- return;
-
- // Verify that the function takes one or two arguments (depending on
- // the function).
- if (FTP->getNumArgs() != (identifierid < 4 ? 1 : 2))
- return;
-
- // The arguments must be integers.
- for (unsigned i = 0; i < FTP->getNumArgs(); i++)
- if (! FTP->getArgType(i)->isIntegerType())
- return;
-
- // Issue a warning.
- llvm::SmallString<256> buf1;
- llvm::raw_svector_ostream os1(buf1);
- os1 << "Return value is not checked in call to '" << FD << '\'';
-
- llvm::SmallString<256> buf2;
- llvm::raw_svector_ostream os2(buf2);
- os2 << "The return value from the call to '" << FD
- << "' is not checked. If an error occurs in '" << FD
- << "', the following code may execute with unexpected privileges";
-
- SourceRange R = CE->getCallee()->getSourceRange();
- BR.EmitBasicReport(os1.str(), "Security", os2.str(),CE->getLocStart(), &R, 1);
-}
-
-//===----------------------------------------------------------------------===//
-// Entry point for check.
-//===----------------------------------------------------------------------===//
-
-void clang::CheckSecuritySyntaxOnly(const Decl *D, BugReporter &BR) {
- WalkAST walker(BR);
- walker.Visit(D->getBody());
-}
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