/SW_Security_Intro

Primary LanguageC

SW Security

Java exception

/Directory/Java/

Version : Java-8

File : ExeptFile.java

In this class there are 2 implementions:

  1. We use a null value in case an object is required

  2. We did not catch NullPointerException or one of its ancestors......

public ExeptFile()-->Default Constractor of class , receive null

public ExeptFile (String path) throws IOException-->Constractor that receiv String (path)

public void write_to_path (String file) throws IOException --> try to write with file

public static void test_ExptFile1()-->TEST 1

public static void test_ExptFile2() --> Test 2

Explain:

From the CERT guidelines below, demonstrate the two issues:

ERR08-J. Do not catch NullPointerException or any of its ancestors

and

EXP01-J. Do not use a null in a case where an object is required

RUN

Path: .

./directory\JAVA\" && javac ExeptFile.java && java ExeptFile

GCC Sanitize Options

/Directory/C

Explain :

GCC supports a number of command-line options that control adding run-time instrumentation to the code it normally generates. For example, one purpose of instrumentation is collect profiling statistics for use in finding program hot spots, code coverage analysis, or profile-guided optimizations. Another class of program instrumentation is adding run-time checking to detect programming errors like invalid pointer dereferences or out-of-bounds array accesses, as well as deliberately hostile attacks such as stack smashing or C++ vtable hijacking. There is also a general hook which can be used to implement other forms of tracing or function-level instrumentation for debug or program analysis purposes.

The purpose:

Small C-language program including four functions each demonstrating a different issue of your choice flagged by GCC-sanitizer.

  • Compiling correctly and not flagged by gcc compiler without –fsanitize=< option >

  • Relevant –fsanitize=< option> shall flag the issue.

1) MemoryNoFree()

Command: gcc -fsanitize=leak

ERROR: LeakSanitizer: detected memory leaks

But: Assign memory and do not release it after which will create a memory leak

Path: directory/C/LeakSanitizer.c

2) Stack_Out_OF_BOUNDS()

Command: gcc -fsanitize=address

ERROR: AddressSanitizer: stack-buffer-overflow on address <--> at pc <--> bp <--> sp <-->

But: I create an array of specific size (in our case of index size), and I try to access the element INDEX + 1 (which does not exist)

Path: directory/C/Stack_Out_OF_BOUNDS.c

3) Undefined()

Command: gcc -fsanitize=undefined

ERROR: runtime error: signed integer overflow: 2147483647 + 1 cannot be represented in type 'int'

But: Each variable has a maximum value which defines it, in our case we have price NT_MAX which is defined by +2147483647 (maximum value of an int) and we try to cross this limit

Path: directory/C/Undefined.c

4) UsingAddressSanitizer()

Command: gcc fsanitize=Address

ERROR: AddressSanitizer: heap-use-after-free

But: In this example, I'm going to allocate memory to my array, then I'm going to free it and try to read this address (which is already free)

Path: directory/C/usingAddressSanitizer.c

RUN

make _______ :

  • WITHOUT_FLAG_ALL--> Run All example without flag

  • clean--> Delete all unnecessary files

  • LeakFlag--> Lunch MemoryNoFree.c with Flag

  • StackFlag--> Lunch Stack_Out_OF_BOUNDS.c with Flag

  • UndeFlag--> Lunch Undefined.c With Flag

  • AdressFlag--> Lunch UsingAddressSanitizer.c With Flag

Author

Shimon Mimoun