From a055976125c705aa4e5f627447bc52651ba7fedb Mon Sep 17 00:00:00 2001
From: "Namhyeon, Go" <gnh1201@gmail.com>
Date: Mon, 19 Feb 2024 07:58:44 +0900
Subject: [PATCH] Update server.py

---
 server.py | 50 ++++++++++++++++++++++++++++++++++++++------------
 1 file changed, 38 insertions(+), 12 deletions(-)

diff --git a/server.py b/server.py
index 73f4b7c..4bbf298 100644
--- a/server.py
+++ b/server.py
@@ -14,6 +14,7 @@ import json
 import ssl
 import time
 import re
+import hashlib
 import resource
 import traceback
 from subprocess import Popen, PIPE
@@ -23,6 +24,8 @@ from platform import python_version
 import requests
 from decouple import config
 
+notify_server = 'catswords.social'
+
 try:
     listening_port = config('PORT', cast=int)
     server_url = config('SERVER_URL')
@@ -162,13 +165,13 @@ def proxy_check_filtered(data, webserver, port, scheme, method, url):
     # convert to text
     text = data.decode(client_encoding, errors='ignore')
 
-    #filtered = text.find('@misskey.io') > -1
-    #filtered = filtered or text.find("https://misskey.io") > -1
-    filtered = filtered or text.find('ctkpaarr') > -1
-    filtered = filtered or bool(re.search(r'\b\w{10}@(?:\w+\.)+\w+\b', text))
-    filtered = filtered or bool(re.search(r"https://[^\s/@]+@([a-zA-Z0-9]{10})", text))
-    filtered = filtered or bool(re.search(r'https://[a-zA-Z0-9.-]+/users/[a-zA-Z0-9]{10}/statuses/[0-9]+', text))
+    # ID filtering with K-Anonymity
+    pattern = r'[/@]([a-zA-Z0-9]{10})(?![a-zA-Z0-9])'
+    matches = re.findall(pattern, text)
+    if len(matches) > 0:
+        filtered = not all(map(validate_string_with_k_anonymity, matches))
 
+    # take action
     if filtered:
         print ("[*] Filtered from %s:%s" % (webserver.decode(client_encoding), str(port)))
 
@@ -184,10 +187,6 @@ def proxy_check_filtered(data, webserver, port, scheme, method, url):
         except Exception as e:
             print ("[*] Failed to save the file: %s" % (str(e)))
 
-        #print ("[*] ====== start preview data =====")
-        #print ("%s" % (text))
-        #print ("[*] ====== end preview data =====")
-
     return filtered
 
 def proxy_server(webserver, port, scheme, method, url, conn, addr, data):
@@ -326,11 +325,11 @@ def add_filtered_host(domain, ip_address):
         with open(hosts_path, 'w') as file:
             file.writelines(lines)
         if user_token != '':    # notify to catswords.social
-            post_status(f"[catswords.social]\r\n\r\n{domain} is a domain with suspicious spam activity.\r\n\r\n\#catswords")
+            post_status(f"[{notify_server} user]\r\n\r\n{domain} is a domain with suspicious spam activity.\r\n\r\n#catswords")
 
 # notify to catswords.social
 def post_status(text, media_ids=None, poll_options=None, poll_expires_in=None, scheduled_at=None, idempotency_key=None):
-    url = "https://catswords.social/api/v1/statuses"
+    url = f"https://{notify_server}/api/v1/statuses"
     headers = {
         "Authorization": f"Bearer {user_token}",
         "Content-Type": "application/x-www-form-urlencoded",
@@ -348,5 +347,32 @@ def post_status(text, media_ids=None, poll_options=None, poll_expires_in=None, s
     response = requests.post(url, headers=headers, data=form_data)
     return response.json()
 
+# k-anonymity validation
+def validate_string_with_k_anonymity(s):
+    # SHA1 of the password
+    p_sha1 = hashlib.sha1(s.encode()).hexdigest()
+
+    # First 5 char of SHA1 for k-anonymity API use
+    f5_sha1 = p_sha1[:5]
+
+    # Last 5 char of SHA1 to match API output
+    l5_sha1 = p_sha1[-5:]
+
+    # Making GET request using Requests library
+    response = requests.get(f'https://api.pwnedpasswords.com/range/{f5_sha1}')
+
+    # Checking if request was successful
+    if response.status_code == 200:
+        # Parsing response text
+        hashes = response.text.split('\r\n')
+
+        # Using list comprehension to find matching hashes
+        matching_hashes = [line for line in hashes if l5_sha1 in line.lower()]
+
+        # If there are matching hashes, return True, else return False
+        return bool(matching_hashes)
+    else:
+        return False
+
 if __name__== "__main__":
     start()