From e3326dea9f698bcdd5365d31db17d839cc17414f Mon Sep 17 00:00:00 2001
From: Brandon Rozek <brozek@brandonrozek.com>
Date: Sat, 6 Jan 2024 13:58:48 -0500
Subject: [PATCH] Fixed authentication issues

---
 pubnix.py | 35 +++++++++++++++++++++++++++--------
 server.py | 15 +++++++++------
 2 files changed, 36 insertions(+), 14 deletions(-)

diff --git a/pubnix.py b/pubnix.py
index 4ae521b..afa3019 100644
--- a/pubnix.py
+++ b/pubnix.py
@@ -69,10 +69,13 @@ def run_simple_server(address, fn, force_auth=True):
             print("Stopping server...")
 
 @contextmanager
-def start_server(address):
+def start_server(address, allow_other=True):
     """
     Opens up a unix domain socket at the specified address
     and listens for connections.
+
+    allow_other: Allow other users on the system to connect
+    to the unix domain socket
     """
     if os.path.exists(address):
         print(f"{address} exists -- server already running")
@@ -84,6 +87,11 @@ def start_server(address):
     sock.bind(address)
     sock.listen()
 
+    if allow_other:
+        # 33279 = '-rwxrwxrwx.'
+        os.chmod("game.sock", 33279)
+        os.chmod("challenges", 33279)
+
     try:
         yield sock
     finally:
@@ -106,10 +114,12 @@ def client_connection(sock):
         connection.close()
 
 def generate_challenge(user):
+    SERVER_FOLDER = Path(__file__).parent.absolute()
+    Path(f"{SERVER_FOLDER}/challenges").mkdir(mode=33279, exist_ok=True)
     return ChallengeMessage(
         username=user,
         token=generate_token(TOKEN_LENGTH),
-        location=f"/home/{user}/.pubnix_challenge"
+        location=f"{SERVER_FOLDER}/challenges/.{user}_challenge"
     )
 
 def authenticate(connection):
@@ -126,7 +136,7 @@ def authenticate(connection):
 
     # Check that challenge file exists
     if not os.path.exists(challenge.location):
-        close_with_error(connection, "Challange file doesn't exist")
+        close_with_error(connection, f"Authentication Error: Challange file doesn't exist at {challenge.location}")
     
     # Check if user owns the file
     if find_owner(challenge.location) != user: 
@@ -175,9 +185,10 @@ def run_simple_client(address, fn, force_auth=True):
     """
     with start_client(address) as client:
         if force_auth:
-            user = login(client)
-        send_message(client, StartMessage())
-        fn(client, user)
+            user, success = login(client)
+        if not force_auth or success:
+            send_message(client, StartMessage())
+            fn(client, user)
 
 @contextmanager
 def start_client(address):
@@ -213,12 +224,16 @@ def login(connection):
     send_message(connection, ValidationMessage())
 
     # On success, delete challenge file
+    success = True
     try:
         message = receive_message(connection, AuthSuccessMessage)
+    except ProtocolException as e:
+        print(e)
+        success = False
     finally:
         os.unlink(challenge.location)
     
-    return user
+    return user, success
 
 ##
 # Messages
@@ -244,7 +259,11 @@ def receive_message(connection, cls=None):
         try:
             message = cls(**message)
         except (TypeError, AssertionError):
-            close_with_error(connection, "Expected message of type")
+            if "type" in message and message['type'] == "error":
+                raise ProtocolException(message.get("message"))
+            else:
+                print("Received:", message, flush=True)
+                close_with_error(connection, f"Expected message of type {cls}")
 
     return message
 
diff --git a/server.py b/server.py
index fe1b114..357e0c7 100644
--- a/server.py
+++ b/server.py
@@ -41,11 +41,12 @@ class WordGuessServer:
         """
         # 33152 = '-rw-------.'
         # 33188 = '-rw-r--r--.'
+        SERVER_FOLDER = Path(__file__).parent.absolute()
         os.chmod(__file__, 33152)
-        os.chmod("pubnix.py", 33188)
-        os.chmod("wordguess.py", 33188)
-        os.chmod("words.txt", 33188)
-        os.chmod("client.py", 33188)
+        os.chmod(f"{SERVER_FOLDER}/pubnix.py", 33188)
+        os.chmod(f"{SERVER_FOLDER}/wordguess.py", 33188)
+        os.chmod(f"{SERVER_FOLDER}/words.txt", 33188)
+        os.chmod(f"{SERVER_FOLDER}/client.py", 33188)
         Path(WordGuess.RESULTS_LOCATION).touch(33188)
         Path(SAVE_LOCATION).touch(33152)
 
@@ -219,13 +220,13 @@ def make_default_dict_false():
 def make_default_dict_set():
     return defaultdict(set)
 
-SAVE_LOCATION = "state.pickle"
+SERVER_FOLDER = Path(__file__).parent.absolute()
+SAVE_LOCATION = f"{SERVER_FOLDER}/state.pickle"
 
 if __name__ == "__main__":
     # NOTE: The seed must be kept secret otherwise
     # players can cheat!
     SEED = random.randint(3, 1000000)
-    print("Seed: ", SEED)
 
     w = WordGuessServer(SEED)
 
@@ -235,6 +236,8 @@ if __name__ == "__main__":
             w = pickle.load(file)
             print("Successfully loaded game state")
 
+    print("Seed: ", w.seed)
+    
     # Make sure permissions are correct
     # to prevent cheating...
     w.fix_permissions()