From 6904e909c685baf8d9e74d1b9e96b521b11a37d8 Mon Sep 17 00:00:00 2001
From: Michael Chen <git@cnml.de>
Date: Tue, 17 May 2022 13:06:14 +0200
Subject: [PATCH] Added challenge 247

---
 247/level3.flag.txt.enc | Bin 0 -> 31 bytes
 247/level3.hash.bin     |   1 +
 247/level3.py           |  45 ++++++++++++++++++++++++++++++++++++++++
 3 files changed, 46 insertions(+)
 create mode 100644 247/level3.flag.txt.enc
 create mode 100644 247/level3.hash.bin
 create mode 100644 247/level3.py

diff --git a/247/level3.flag.txt.enc b/247/level3.flag.txt.enc
new file mode 100644
index 0000000000000000000000000000000000000000..7a105e9087add7872598a8ebb11cc2a9c50c8b75
GIT binary patch
literal 31
mcmZ?dVTvs>RQHSt42jBP=4Fm&3Wy1_3J>9kWnklAmH_~Aa0Ye&

literal 0
HcmV?d00001

diff --git a/247/level3.hash.bin b/247/level3.hash.bin
new file mode 100644
index 0000000..db40f9c
--- /dev/null
+++ b/247/level3.hash.bin
@@ -0,0 +1 @@
+�`E��BC�;���Ϣi�
\ No newline at end of file
diff --git a/247/level3.py b/247/level3.py
new file mode 100644
index 0000000..7c4d340
--- /dev/null
+++ b/247/level3.py
@@ -0,0 +1,45 @@
+import hashlib
+
+### THIS FUNCTION WILL NOT HELP YOU FIND THE FLAG --LT ########################
+def str_xor(secret, key):
+    #extend key to secret length
+    new_key = key
+    i = 0
+    while len(new_key) < len(secret):
+        new_key = new_key + key[i]
+        i = (i + 1) % len(key)        
+    return "".join([chr(ord(secret_c) ^ ord(new_key_c)) for (secret_c,new_key_c) in zip(secret,new_key)])
+###############################################################################
+
+flag_enc = open('level3.flag.txt.enc', 'rb').read()
+correct_pw_hash = open('level3.hash.bin', 'rb').read()
+
+
+def hash_pw(pw_str):
+    pw_bytes = bytearray()
+    pw_bytes.extend(pw_str.encode())
+    m = hashlib.md5()
+    m.update(pw_bytes)
+    return m.digest()
+
+
+def level_3_pw_check():
+    user_pw = input("Please enter correct password for flag: ")
+    user_pw_hash = hash_pw(user_pw)
+    
+    if( user_pw_hash == correct_pw_hash ):
+        print("Welcome back... your flag, user:")
+        decryption = str_xor(flag_enc.decode(), user_pw)
+        print(decryption)
+        return
+    print("That password is incorrect")
+
+
+
+level_3_pw_check()
+
+
+# The strings below are 7 possibilities for the correct password. 
+#   (Only 1 is correct)
+pos_pw_list = ["8799", "d3ab", "1ea2", "acaf", "2295", "a9de", "6f3d"]
+