[clang-tools-extra] r285809 - Add a new clang-tidy check for cert-msc50-cpp (and cert-msc30-c) that corresponds to the CERT C++ secure coding rule: https://www.securecoding.cert.org/confluence/display/cplusplus/MSC50-CPP.+Do+not+use+std%3A%3Arand%28%29+for+generating+pseudorandom+numbers
Aaron Ballman via cfe-commits
cfe-commits at lists.llvm.org
Wed Nov 2 07:16:36 PDT 2016
Author: aaronballman
Date: Wed Nov 2 09:16:36 2016
New Revision: 285809
URL: http://llvm.org/viewvc/llvm-project?rev=285809&view=rev
Log:
Add a new clang-tidy check for cert-msc50-cpp (and cert-msc30-c) that corresponds to the CERT C++ secure coding rule: https://www.securecoding.cert.org/confluence/display/cplusplus/MSC50-CPP.+Do+not+use+std%3A%3Arand%28%29+for+generating+pseudorandom+numbers
Patch by Benedek Kiss
Added:
clang-tools-extra/trunk/clang-tidy/cert/LimitedRandomnessCheck.cpp
clang-tools-extra/trunk/clang-tidy/cert/LimitedRandomnessCheck.h
clang-tools-extra/trunk/docs/clang-tidy/checks/cert-msc30-c.rst
clang-tools-extra/trunk/docs/clang-tidy/checks/cert-msc50-cpp.rst
clang-tools-extra/trunk/test/clang-tidy/cert-limited-randomness.c
clang-tools-extra/trunk/test/clang-tidy/cert-limited-randomness.cpp
Modified:
clang-tools-extra/trunk/clang-tidy/cert/CERTTidyModule.cpp
clang-tools-extra/trunk/clang-tidy/cert/CMakeLists.txt
clang-tools-extra/trunk/docs/clang-tidy/checks/list.rst
Modified: clang-tools-extra/trunk/clang-tidy/cert/CERTTidyModule.cpp
URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/clang-tidy/cert/CERTTidyModule.cpp?rev=285809&r1=285808&r2=285809&view=diff
==============================================================================
--- clang-tools-extra/trunk/clang-tidy/cert/CERTTidyModule.cpp (original)
+++ clang-tools-extra/trunk/clang-tidy/cert/CERTTidyModule.cpp Wed Nov 2 09:16:36 2016
@@ -18,6 +18,7 @@
#include "../misc/ThrowByValueCatchByReferenceCheck.h"
#include "CommandProcessorCheck.h"
#include "FloatLoopCounter.h"
+#include "LimitedRandomnessCheck.h"
#include "SetLongJmpCheck.h"
#include "StaticObjectExceptionCheck.h"
#include "StrToNumCheck.h"
@@ -53,6 +54,9 @@ public:
"cert-err60-cpp");
CheckFactories.registerCheck<misc::ThrowByValueCatchByReferenceCheck>(
"cert-err61-cpp");
+ // MSC
+ CheckFactories.registerCheck<LimitedRandomnessCheck>(
+ "cert-msc50-cpp");
// C checkers
// DCL
@@ -70,6 +74,9 @@ public:
// ERR
CheckFactories.registerCheck<StrToNumCheck>(
"cert-err34-c");
+ // MSC
+ CheckFactories.registerCheck<LimitedRandomnessCheck>(
+ "cert-msc30-c");
}
ClangTidyOptions getModuleOptions() override {
ClangTidyOptions Options;
Modified: clang-tools-extra/trunk/clang-tidy/cert/CMakeLists.txt
URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/clang-tidy/cert/CMakeLists.txt?rev=285809&r1=285808&r2=285809&view=diff
==============================================================================
--- clang-tools-extra/trunk/clang-tidy/cert/CMakeLists.txt (original)
+++ clang-tools-extra/trunk/clang-tidy/cert/CMakeLists.txt Wed Nov 2 09:16:36 2016
@@ -4,6 +4,7 @@ add_clang_library(clangTidyCERTModule
CERTTidyModule.cpp
CommandProcessorCheck.cpp
FloatLoopCounter.cpp
+ LimitedRandomnessCheck.cpp
SetLongJmpCheck.cpp
StaticObjectExceptionCheck.cpp
StrToNumCheck.cpp
Added: clang-tools-extra/trunk/clang-tidy/cert/LimitedRandomnessCheck.cpp
URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/clang-tidy/cert/LimitedRandomnessCheck.cpp?rev=285809&view=auto
==============================================================================
--- clang-tools-extra/trunk/clang-tidy/cert/LimitedRandomnessCheck.cpp (added)
+++ clang-tools-extra/trunk/clang-tidy/cert/LimitedRandomnessCheck.cpp Wed Nov 2 09:16:36 2016
@@ -0,0 +1,40 @@
+//===--- LimitedRandomnessCheck.cpp - clang-tidy---------------------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "LimitedRandomnessCheck.h"
+#include "clang/AST/ASTContext.h"
+#include "clang/ASTMatchers/ASTMatchFinder.h"
+
+using namespace clang::ast_matchers;
+
+namespace clang {
+namespace tidy {
+namespace cert {
+
+void LimitedRandomnessCheck::registerMatchers(MatchFinder *Finder) {
+ Finder->addMatcher(callExpr(callee(functionDecl(namedDecl(hasName("::rand")),
+ parameterCountIs(0))))
+ .bind("randomGenerator"),
+ this);
+}
+
+void LimitedRandomnessCheck::check(const MatchFinder::MatchResult &Result) {
+ std::string msg = "";
+ if (getLangOpts().CPlusPlus)
+ msg = "; use C++11 random library instead";
+
+ const auto *MatchedDecl = Result.Nodes.getNodeAs<CallExpr>("randomGenerator");
+ diag(MatchedDecl->getLocStart(),
+ "rand() has limited randomness" + msg);
+}
+
+} // namespace cert
+} // namespace tidy
+} // namespace clang
+
Added: clang-tools-extra/trunk/clang-tidy/cert/LimitedRandomnessCheck.h
URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/clang-tidy/cert/LimitedRandomnessCheck.h?rev=285809&view=auto
==============================================================================
--- clang-tools-extra/trunk/clang-tidy/cert/LimitedRandomnessCheck.h (added)
+++ clang-tools-extra/trunk/clang-tidy/cert/LimitedRandomnessCheck.h Wed Nov 2 09:16:36 2016
@@ -0,0 +1,38 @@
+//===--- LimitedRandomnessCheck.h - clang-tidy-------------------*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CERT_LIMITED_RANDOMNESS_H
+#define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CERT_LIMITED_RANDOMNESS_H
+
+#include "../ClangTidy.h"
+
+namespace clang {
+namespace tidy {
+namespace cert {
+
+/// Pseudorandom number generators are not genuinely random. The result of the
+/// std::rand() function makes no guarantees as to the quality of the random
+/// sequence produced.
+/// This check warns for the usage of std::rand() function.
+///
+/// For the user-facing documentation see:
+/// http://clang.llvm.org/extra/clang-tidy/checks/cert-msc50-cpp.html
+class LimitedRandomnessCheck : public ClangTidyCheck {
+public:
+ LimitedRandomnessCheck(StringRef Name, ClangTidyContext *Context)
+ : ClangTidyCheck(Name, Context) {}
+ void registerMatchers(ast_matchers::MatchFinder *Finder) override;
+ void check(const ast_matchers::MatchFinder::MatchResult &Result) override;
+};
+
+} // namespace cert
+} // namespace tidy
+} // namespace clang
+
+#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CERT_LIMITED_RANDOMNESS_H
Added: clang-tools-extra/trunk/docs/clang-tidy/checks/cert-msc30-c.rst
URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/docs/clang-tidy/checks/cert-msc30-c.rst?rev=285809&view=auto
==============================================================================
--- clang-tools-extra/trunk/docs/clang-tidy/checks/cert-msc30-c.rst (added)
+++ clang-tools-extra/trunk/docs/clang-tidy/checks/cert-msc30-c.rst Wed Nov 2 09:16:36 2016
@@ -0,0 +1,7 @@
+.. title:: clang-tidy - cert-msc30-c
+
+cert-msc30-c
+============
+
+The cert-msc30-c check is an alias, please see
+`cert-msc50-cpp <cert-msc50-cpp.html>`_ for more information.
Added: clang-tools-extra/trunk/docs/clang-tidy/checks/cert-msc50-cpp.rst
URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/docs/clang-tidy/checks/cert-msc50-cpp.rst?rev=285809&view=auto
==============================================================================
--- clang-tools-extra/trunk/docs/clang-tidy/checks/cert-msc50-cpp.rst (added)
+++ clang-tools-extra/trunk/docs/clang-tidy/checks/cert-msc50-cpp.rst Wed Nov 2 09:16:36 2016
@@ -0,0 +1,6 @@
+.. title:: clang-tidy - cert-msc50-cpp
+
+cert-msc50-cpp
+==============
+
+Pseudorandom number generators use mathematical algorithms to produce a sequence of numbers with good statistical properties, but the numbers produced are not genuinely random. The ``std::rand()`` function takes a seed (number), runs a mathematical operation on it and returns the result. By manipulating the seed the result can be predictible. This check warns for the usage of ``std::rand()``.
Modified: clang-tools-extra/trunk/docs/clang-tidy/checks/list.rst
URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/docs/clang-tidy/checks/list.rst?rev=285809&r1=285808&r2=285809&view=diff
==============================================================================
--- clang-tools-extra/trunk/docs/clang-tidy/checks/list.rst (original)
+++ clang-tools-extra/trunk/docs/clang-tidy/checks/list.rst Wed Nov 2 09:16:36 2016
@@ -18,6 +18,8 @@ Clang-Tidy Checks
cert-err61-cpp (redirects to misc-throw-by-value-catch-by-reference) <cert-err61-cpp>
cert-fio38-c (redirects to misc-non-copyable-objects) <cert-fio38-c>
cert-flp30-c
+ cert-msc30-c (redirects to cert-limited-randomness) <cert-msc30-c>
+ cert-msc50-cpp
cert-oop11-cpp (redirects to misc-move-constructor-init) <cert-oop11-cpp>
cppcoreguidelines-interfaces-global-init
cppcoreguidelines-pro-bounds-array-to-pointer-decay
Added: clang-tools-extra/trunk/test/clang-tidy/cert-limited-randomness.c
URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/test/clang-tidy/cert-limited-randomness.c?rev=285809&view=auto
==============================================================================
--- clang-tools-extra/trunk/test/clang-tidy/cert-limited-randomness.c (added)
+++ clang-tools-extra/trunk/test/clang-tidy/cert-limited-randomness.c Wed Nov 2 09:16:36 2016
@@ -0,0 +1,13 @@
+// RUN: %check_clang_tidy %s cert-msc30-c %t
+
+extern int rand(void);
+int nonrand();
+
+int cTest() {
+ int i = rand();
+ // CHECK-MESSAGES: :[[@LINE-1]]:11: warning: rand() has limited randomness [cert-msc30-c]
+
+ int k = nonrand();
+
+ return 0;
+}
Added: clang-tools-extra/trunk/test/clang-tidy/cert-limited-randomness.cpp
URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/test/clang-tidy/cert-limited-randomness.cpp?rev=285809&view=auto
==============================================================================
--- clang-tools-extra/trunk/test/clang-tidy/cert-limited-randomness.cpp (added)
+++ clang-tools-extra/trunk/test/clang-tidy/cert-limited-randomness.cpp Wed Nov 2 09:16:36 2016
@@ -0,0 +1,28 @@
+// RUN: %check_clang_tidy %s cert-msc50-cpp %t
+
+int rand();
+int rand(int);
+
+namespace std {
+using ::rand;
+}
+
+namespace nonstd {
+ int rand();
+}
+
+void testFunction1() {
+ int i = std::rand();
+ // CHECK-MESSAGES: :[[@LINE-1]]:11: warning: rand() has limited randomness; use C++11 random library instead [cert-msc50-cpp]
+
+ int j = ::rand();
+ // CHECK-MESSAGES: :[[@LINE-1]]:11: warning: rand() has limited randomness; use C++11 random library instead [cert-msc50-cpp]
+
+ int k = rand(i);
+
+ int l = nonstd::rand();
+
+ int m = rand();
+ // CHECK-MESSAGES: :[[@LINE-1]]:11: warning: rand() has limited randomness; use C++11 random library instead [cert-msc50-cpp]
+}
+
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