CheckBufferOverrun; Added files

CheckBufferOverrun.cpp

@@ -0,0 +1,157 @@
+//---------------------------------------------------------------------------
+#include "CheckBufferOverrun.h"
+#include "Tokenize.h"
+#include "CommonCheck.h"
+
+#include <sstream>
+
+#include <stdlib.h>     // <- strtoul
+
+extern bool IsNumber(const char str[]);
+
+//---------------------------------------------------------------------------
+
+
+
+//---------------------------------------------------------------------------
+// Buffer overrun..
+//---------------------------------------------------------------------------
+
+void CheckBufferOverrun()
+{
+    int indentlevel = 0;
+    for (TOKEN *tok = tokens; tok; tok = tok->next)
+    {
+        if (tok->str[0]=='{')
+            indentlevel++;
+
+        else if (tok->str[0]=='}')
+            indentlevel--;
+
+        else if (indentlevel > 0)
+        {
+            // Declaring array..
+            if (match(tok, "type var [ num ] ;"))
+            {
+                const char *varname = getstr(tok,1);
+                unsigned int size = strtoul(getstr(tok,3), NULL, 10);
+                int _indentlevel = indentlevel;
+                for (TOKEN *tok2 = gettok(tok,5); tok2; tok2 = tok2->next)
+                {
+                    if (tok2->str[0]=='{')
+                    {
+                        _indentlevel++;
+                    }
+                    else if (tok2->str[0]=='}')
+                    {
+                        _indentlevel--;
+                        if (_indentlevel < indentlevel)
+                            break;
+                    }
+                    else
+                    {
+                        // Array index..
+                        if (strcmp(tok2->str,varname)==0 &&
+                            strcmp(getstr(tok2,1),"[")==0 &&
+                            IsNumber(getstr(tok2,2)) &&
+                            strcmp(getstr(tok2,3),"]")==0 )
+                        {
+                            const char *str = getstr(tok2, 2);
+                            if (strtoul(str, NULL, 10) >= size)
+                            {
+                                std::ostringstream ostr;
+                                ostr << FileLine(tok2) << ": Array index out of bounds";
+                                ReportErr(ostr.str());
+                            }
+                        }
+
+                        // Loop..
+                        const char *strindex = 0;
+                        int value = 0;
+                        if (match(tok2,"for ( var = 0 ; var < num ; var + + )"))
+                        {
+                            strindex = getstr(tok2,2);
+                            value = atoi(getstr(tok2,8));
+                        }
+                        else if (match(tok2,"for ( var = 0 ; var <= num ; var + + )"))
+                        {
+                            strindex = getstr(tok2,2);
+                            value = 1 + atoi(getstr(tok2,8));
+                        }
+                        else if (match(tok2,"for ( var = 0 ; var < num ; + + var )"))
+                        {
+                            strindex = getstr(tok2,2);
+                            value = atoi(getstr(tok2,8));
+                        }
+                        else if (match(tok2,"for ( var = 0 ; var <= num ; + + var )"))
+                        {
+                            strindex = getstr(tok2,2);
+                            value = 1 + atoi(getstr(tok2,8));
+                        }
+                        if (strindex && value>(int)size)
+                        {
+                            TOKEN *tok3 = tok2;
+                            while (tok3 && strcmp(tok3->str,")"))
+                                tok3 = tok3->next;
+                            if (!tok3)
+                                break;
+                            tok3 = tok3->next;
+                            if (tok3->str[0] == '{')
+                                tok3 = tok3->next;
+                            while (tok3 && !strchr(";}",tok3->str[0]))
+                            {
+                                if (strcmp(tok3->str,varname)==0 &&
+                                    strcmp(getstr(tok3,1),"[")==0 &&
+                                    strcmp(getstr(tok3,2),strindex)==0 &&
+                                    strcmp(getstr(tok3,3),"]")==0 )
+                                {
+                                    std::ostringstream ostr;
+                                    ostr << FileLine(tok3) << ": Buffer overrun";
+                                    ReportErr(ostr.str());
+                                    break;
+                                }
+                                tok3 = tok3->next;
+                            }
+                        }
+
+
+                        // Writing data into array..
+                        if (match(tok2,"strcpy ( var , "))
+                        {
+                            int len = 0;
+                            if (strcmp(getstr(tok2, 2), varname) == 0)
+                            {
+                                const char *str = getstr(tok2, 4);
+                                if (str[0] == '\"')
+                                {
+                                    while (*str)
+                                    {
+                                        if (*str=='\\')
+                                            str++;
+                                        str++;
+                                        len++;
+                                    }
+                                }
+                            }
+                            if (len > 2 && len >= (int)size + 2)
+                            {
+                                std::ostringstream ostr;
+                                ostr << FileLine(tok2) << ": Buffer overrun";
+                                ReportErr(ostr.str());
+                            }
+                        }
+                    }
+                }
+            }
+        }
+    }
+}
+//---------------------------------------------------------------------------
+
+
+
+
+
+
+
+

CheckBufferOverrun.h

@@ -0,0 +1,11 @@
+//---------------------------------------------------------------------------
+#ifndef CheckBufferOverrunH
+#define CheckBufferOverrunH
+//---------------------------------------------------------------------------
+
+// Buffer overrun..
+void CheckBufferOverrun();
+
+//---------------------------------------------------------------------------
+#endif
+