From 055c31519e74e77c86fab48c3810602c32692d28 Mon Sep 17 00:00:00 2001
From: Sascha Tommasone <sascha@tommasone.me>
Date: Sat, 8 Jun 2024 18:13:36 +0200
Subject: [PATCH] [Assignment-5] setup task 3 (shellcode)

---
 .../shellcode/Makefile                           | 12 ++++++++++++
 .../shellcode/shellcode.asm                      |  8 ++++++++
 .../shellcode/test_shellcode.c                   | 16 ++++++++++++++++
 3 files changed, 36 insertions(+)
 create mode 100644 Assignment 5 - Software Security - Teil 1/shellcode/Makefile
 create mode 100644 Assignment 5 - Software Security - Teil 1/shellcode/shellcode.asm
 create mode 100644 Assignment 5 - Software Security - Teil 1/shellcode/test_shellcode.c

diff --git a/Assignment 5 - Software Security - Teil 1/shellcode/Makefile b/Assignment 5 - Software Security - Teil 1/shellcode/Makefile
new file mode 100644
index 0000000..e328bc3
--- /dev/null
+++ b/Assignment 5 - Software Security - Teil 1/shellcode/Makefile	
@@ -0,0 +1,12 @@
+.DEFAULT_GOAL := all
+
+shellcode: shellcode.asm
+	nasm -felf32 shellcode.asm -o shellcode.o
+	ld -m elf_i386 shellcode.o -o shellcode
+	rm shellcode.o
+
+test: test_shellcode.c
+	gcc -o test_shellcode -m32 -fno-stack-protector -z execstack -fno-pie -O0 test_shellcode.c
+
+
+all: shellcode test
diff --git a/Assignment 5 - Software Security - Teil 1/shellcode/shellcode.asm b/Assignment 5 - Software Security - Teil 1/shellcode/shellcode.asm
new file mode 100644
index 0000000..310f6cf
--- /dev/null
+++ b/Assignment 5 - Software Security - Teil 1/shellcode/shellcode.asm	
@@ -0,0 +1,8 @@
+
+; SHELLCODE: "\x90\x90\x90..."
+
+global _start
+_start:
+    ;----------------------------------
+    nop; <YOUR CODE HERE>
+    ; ------------ End of file ------------ 
diff --git a/Assignment 5 - Software Security - Teil 1/shellcode/test_shellcode.c b/Assignment 5 - Software Security - Teil 1/shellcode/test_shellcode.c
new file mode 100644
index 0000000..193077c
--- /dev/null
+++ b/Assignment 5 - Software Security - Teil 1/shellcode/test_shellcode.c	
@@ -0,0 +1,16 @@
+#include <stdio.h>
+#include <string.h>
+
+// gcc -o test_shellcode -m32 -fno-stack-protector -fno-pie -z execstack -O0 test_shellcode.c
+
+// Your shellcode goes here
+char *shellcode = "\x90\x90\x90...";
+// ------------------------
+
+int main()
+{
+    // Print length of shellcode
+    fprintf(stdout,"Length: %d\n",strlen(shellcode));
+    // Execute shellcode
+    (*(void  (*)()) shellcode)();
+}