cppcheck/src/checksecurity.cpp

114 lines
3.3 KiB
C++

/*
* Cppcheck - A tool for static C/C++ code analysis
* Copyright (C) 2007-2009 Daniel Marjamäki, Reijo Tomperi, Nicolas Le Cam,
* Leandro Penz, Kimmo Varis, Vesa Pikki
*
* 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/
*/
#include "checksecurity.h"
#include "errorlogger.h"
#include "token.h"
#include "tokenize.h"
CheckSecurity::CheckSecurity(const Tokenizer *tokenizer, ErrorLogger *errorLogger)
: _tokenizer(tokenizer), _errorLogger(errorLogger)
{
}
CheckSecurity::~CheckSecurity()
{
}
/**
* Check that there are input validation when reading number from FILE/stream
*/
void CheckSecurity::readnum()
{
const Token *tok = _tokenizer->tokens();
while (tok)
{
unsigned int varId = 0;
// Search for a variable declaration
while (tok)
{
if (Token::Match(tok, "int %var% ;"))
{
varId = tok->next()->varId();
break;
}
tok = tok->next();
}
// Skip ahead a little with tok..
tok = tok->tokAt(2);
// Now take a look at the variable usage..
if (varId == 0)
continue;
// Search for bad input..
for (const Token *tok2 = tok; tok2; tok2 = tok2->next())
{
if (Token::Match(tok2, "cin >> %varid%", varId))
_errorLogger->unvalidatedInput(_tokenizer, tok2);
if (Token::Match(tok2, "fscanf ( %var% , %str% , %varid%", varId))
_errorLogger->unvalidatedInput(_tokenizer, tok2);
if (Token::Match(tok2, "scanf ( %str% , %varid%", varId))
_errorLogger->unvalidatedInput(_tokenizer, tok2);
}
}
}
/**
* Read data from Form/GUI
* Todo: This function must be more customizable to be usable
*/
void CheckSecurity::gui()
{
// input control classes whose values are insecure..
const char *inputclass[] = {"TEdit", 0};
// functions that parse value without validating it..
const std::string dangerousfunc("atoi|atof|strtol|strtoul");
for (unsigned int i = 0; inputclass[i]; ++i)
{
const std::string classname(inputclass[i]);
for (const Token *tok = _tokenizer->tokens(); tok; tok = tok->next())
{
// Declaration..
if (Token::Match(tok, (classname + " * %var% ;|=").c_str()))
{
// Variable name..
const std::string varname(tok->strAt(2));
// Getting the value..
const Token *tok2 = Token::findmatch(tok, (dangerousfunc + " ( " + varname + " .").c_str());
if (tok2)
_errorLogger->unvalidatedInput(_tokenizer, tok2);
}
}
}
}