258 lines
9.3 KiB
C++
258 lines
9.3 KiB
C++
/*
|
|
* Cppcheck - A tool for static C/C++ code analysis
|
|
* Copyright (C) 2007-2011 Daniel Marjamäki and Cppcheck team.
|
|
*
|
|
* This program is free software: you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation, either version 3 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program. If not, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
|
|
//---------------------------------------------------------------------------
|
|
#ifndef CheckBufferOverrunH
|
|
#define CheckBufferOverrunH
|
|
//---------------------------------------------------------------------------
|
|
|
|
#include "check.h"
|
|
#include "settings.h"
|
|
#include "mathlib.h"
|
|
#include <list>
|
|
#include <vector>
|
|
#include <string>
|
|
|
|
class ErrorLogger;
|
|
class Token;
|
|
class Tokenizer;
|
|
class Variable;
|
|
|
|
/// @addtogroup Checks
|
|
/// @{
|
|
|
|
/**
|
|
* @brief buffer overruns and array index out of bounds
|
|
*
|
|
* Buffer overrun and array index out of bounds are pretty much the same.
|
|
* But I generally use 'array index' if the code contains []. And the given
|
|
* index is out of bounds.
|
|
* I generally use 'buffer overrun' if you for example call a strcpy or
|
|
* other function and pass a buffer and reads or writes too much data.
|
|
*/
|
|
class CheckBufferOverrun : public Check
|
|
{
|
|
public:
|
|
|
|
/** This constructor is used when registering the CheckClass */
|
|
CheckBufferOverrun() : Check(myName())
|
|
{ }
|
|
|
|
/** This constructor is used when running checks. */
|
|
CheckBufferOverrun(const Tokenizer *tokenizer, const Settings *settings, ErrorLogger *errorLogger)
|
|
: Check(myName(), tokenizer, settings, errorLogger)
|
|
{ }
|
|
|
|
void runSimplifiedChecks(const Tokenizer *tokenizer, const Settings *settings, ErrorLogger *errorLogger)
|
|
{
|
|
CheckBufferOverrun checkBufferOverrun(tokenizer, settings, errorLogger);
|
|
checkBufferOverrun.bufferOverrun();
|
|
checkBufferOverrun.negativeIndex();
|
|
checkBufferOverrun.arrayIndexThenCheck();
|
|
|
|
/** ExecutionPath checking.. */
|
|
checkBufferOverrun.executionPaths();
|
|
}
|
|
|
|
/** @brief %Check for buffer overruns */
|
|
void bufferOverrun();
|
|
|
|
/** @brief Using array index before bounds check */
|
|
void arrayIndexThenCheck();
|
|
|
|
/** @brief %Check for buffer overruns by inspecting execution paths */
|
|
void executionPaths();
|
|
|
|
/**
|
|
* @brief Get minimum length of format string result
|
|
* @param input_string format string
|
|
* @param parameters given parameters to sprintf
|
|
* @return minimum length of resulting string
|
|
*/
|
|
static MathLib::bigint countSprintfLength(const std::string &input_string, const std::list<const Token*> ¶meters);
|
|
|
|
/**
|
|
* @brief %Check code that matches: "sprintf ( %varid% , %str% [,)]" when varid is not 0,
|
|
* and report found errors.
|
|
* @param tok The "sprintf" token.
|
|
* @param size The size of the buffer where sprintf is writing.
|
|
*/
|
|
void checkSprintfCall(const Token *tok, const MathLib::bigint size);
|
|
|
|
/** Check for buffer overruns - locate struct variables and check them with the .._CheckScope function */
|
|
void checkStructVariable();
|
|
|
|
/** Check for buffer overruns - locate global variables and local function variables and check them with the checkScope function */
|
|
void checkGlobalAndLocalVariable();
|
|
|
|
/** Check for buffer overruns due to allocating strlen(src) bytes instead of (strlen(src)+1) bytes before copying a string */
|
|
void checkBufferAllocatedWithStrlen();
|
|
|
|
/** Check for buffer overruns due to copying command-line args to fixed-sized buffers without bounds checking */
|
|
void checkInsecureCmdLineArgs();
|
|
|
|
/** Check for negative index */
|
|
void negativeIndex();
|
|
|
|
/** Check for buffer overruns */
|
|
void checkScope(const Token *tok, const std::vector<std::string> &varname, const MathLib::bigint size, const MathLib::bigint total_size, unsigned int varid);
|
|
|
|
/** Information about N-dimensional array */
|
|
class ArrayInfo
|
|
{
|
|
private:
|
|
/** number of elements of array */
|
|
std::vector<MathLib::bigint> _num;
|
|
|
|
/** size of each element in array */
|
|
MathLib::bigint _element_size;
|
|
|
|
/** variable id */
|
|
unsigned int _varid;
|
|
|
|
/** full name of variable as pattern */
|
|
std::string _varname;
|
|
|
|
public:
|
|
ArrayInfo();
|
|
ArrayInfo(const ArrayInfo &);
|
|
ArrayInfo(const Variable *var, const Tokenizer *tokenizer);
|
|
ArrayInfo & operator=(const ArrayInfo &ai);
|
|
|
|
/**
|
|
* Create array info with specified data
|
|
* The intention is that this is only a temporary solution.. all
|
|
* checking should be based on ArrayInfo from the start and then
|
|
* this will not be needed as the declare can be used instead.
|
|
*/
|
|
ArrayInfo(unsigned int id, const std::string &name, MathLib::bigint size1, MathLib::bigint n);
|
|
|
|
/** Create a copy ArrayInfo where the number of elements have been limited by a value */
|
|
ArrayInfo limit(MathLib::bigint value) const;
|
|
|
|
/**
|
|
* Declare array - set info
|
|
* \param tok first token in array declaration
|
|
* \param tokenizer The tokenizer (for type size)
|
|
* \return success => true
|
|
*/
|
|
bool declare(const Token *tok, const Tokenizer &tokenizer);
|
|
|
|
/** array sizes */
|
|
const std::vector<MathLib::bigint> &num() const
|
|
{
|
|
return _num;
|
|
}
|
|
|
|
/** array size */
|
|
MathLib::bigint num(size_t index) const
|
|
{
|
|
return _num[index];
|
|
}
|
|
|
|
/** size of each element */
|
|
MathLib::bigint element_size() const
|
|
{
|
|
return _element_size;
|
|
}
|
|
|
|
/** Variable name */
|
|
unsigned int varid() const
|
|
{
|
|
return _varid;
|
|
}
|
|
|
|
/** Variable name */
|
|
const std::string &varname() const
|
|
{
|
|
return _varname;
|
|
}
|
|
};
|
|
|
|
/** Check for buffer overruns (based on ArrayInfo) */
|
|
void checkScope(const Token *tok, const ArrayInfo &arrayInfo);
|
|
|
|
/** Check scope helper function - parse for body */
|
|
void checkScopeForBody(const Token *tok, const ArrayInfo &arrayInfo, bool &bailout);
|
|
|
|
/** Helper function used when parsing for-loops */
|
|
void parse_for_body(const Token *tok2, const ArrayInfo &arrayInfo, const std::string &strindex, bool condition_out_of_bounds, unsigned int counter_varid, const std::string &min_counter_value, const std::string &max_counter_value);
|
|
|
|
/**
|
|
* Helper function for checkFunctionCall - check a function parameter
|
|
* \param tok token for the function name
|
|
* \param par on what parameter is the array used
|
|
* \param arrayInfo the array information
|
|
*/
|
|
void checkFunctionParameter(const Token &tok, const unsigned int par, const ArrayInfo &arrayInfo);
|
|
|
|
/**
|
|
* Helper function that checks if the array is used and if so calls the checkFunctionCall
|
|
* @param tok token that matches "%var% ("
|
|
* @param arrayInfo the array information
|
|
*/
|
|
void checkFunctionCall(const Token *tok, const ArrayInfo &arrayInfo);
|
|
|
|
void arrayIndexOutOfBoundsError(const Token *tok, MathLib::bigint size, MathLib::bigint index);
|
|
void arrayIndexOutOfBoundsError(const Token *tok, const ArrayInfo &arrayInfo, const std::vector<MathLib::bigint> &index);
|
|
void arrayIndexOutOfBoundsError(const std::list<const Token *> &callstack, const ArrayInfo &arrayInfo, const std::vector<MathLib::bigint> &index);
|
|
void bufferOverrunError(const Token *tok, const std::string &varnames = "");
|
|
void strncatUsageError(const Token *tok);
|
|
void outOfBoundsError(const Token *tok, const std::string &what);
|
|
void sizeArgumentAsCharError(const Token *tok);
|
|
void terminateStrncpyError(const Token *tok, const std::string &varname, bool conclusive);
|
|
void negativeIndexError(const Token *tok, MathLib::bigint index);
|
|
void cmdLineArgsError(const Token *tok);
|
|
void pointerOutOfBoundsError(const Token *tok, const std::string &object); // UB when result of calculation is out of bounds
|
|
void arrayIndexThenCheckError(const Token *tok, const std::string &indexName);
|
|
void possibleBufferOverrunError(const Token *tok, const std::string &src, const std::string &dst, bool cat);
|
|
|
|
void getErrorMessages(ErrorLogger *errorLogger, const Settings *settings)
|
|
{
|
|
CheckBufferOverrun c(0, settings, errorLogger);
|
|
c.arrayIndexOutOfBoundsError(0, 2, 2);
|
|
c.bufferOverrunError(0, std::string("buffer"));
|
|
c.strncatUsageError(0);
|
|
c.outOfBoundsError(0, "index");
|
|
c.sizeArgumentAsCharError(0);
|
|
c.terminateStrncpyError(0, "buffer", false);
|
|
c.negativeIndexError(0, -1);
|
|
c.cmdLineArgsError(0);
|
|
c.pointerOutOfBoundsError(0, "array");
|
|
c.arrayIndexThenCheckError(0, "index");
|
|
c.possibleBufferOverrunError(0, "source", "destination", false);
|
|
}
|
|
|
|
std::string myName() const
|
|
{
|
|
return "Bounds checking";
|
|
}
|
|
|
|
std::string classInfo() const
|
|
{
|
|
return "out of bounds checking";
|
|
}
|
|
};
|
|
/// @}
|
|
//---------------------------------------------------------------------------
|
|
#endif
|
|
|
|
|
|
|