From e121bc619a47d885db67da1918ce0b801444b1a5 Mon Sep 17 00:00:00 2001
From: Garrett Dickinson <dickinsongarrett@gmail.com>
Date: Thu, 26 Jan 2023 14:32:06 -0600
Subject: [PATCH] Add code for finding ELF magic number

---
 src/main.rs | 18 ++++++++++++++----
 1 file changed, 14 insertions(+), 4 deletions(-)

diff --git a/src/main.rs b/src/main.rs
index 8702591..9931cda 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -3,24 +3,34 @@ use std::env;
 use std::fs;
 use std::process::exit;
 
+const ELF_MAGIC_NUMBER: &[u8] = &[0x7F,0x45,0x4C,0x46];
+
 fn main() {
+    // Collect our execution args
     let args: Vec<String> = env::args().collect();
 
+    // Grab our filepath from our options
     let file_path = &args[1];
-    println!("Got target file '{}'", file_path);
-
     
     if path::Path::new(file_path).exists() {
         println!("File exists, reading '{}'", file_path);
+        
         let contents: Result<Vec<u8>, std::io::Error> = fs::read(file_path);
+        
         if contents.is_ok() {
             let bytes: &Vec<u8> = &contents.expect("");
-            for byte in bytes {
-                println!("{}", byte);
+            let magic_num: &[u8] = &bytes[0..4];
+        
+            if magic_num == ELF_MAGIC_NUMBER {
+                println!("Found ELF Magic Number!");
+            } else {
+                println!("[Error] Could not find magic number, is this an executable?")
             }
         }
     } else {
         println!("[Error] '{}' does not exist", file_path);
         exit(-1);
     }
+
+    return;
 }