Server working

server/app/models.py

@@ -7,7 +7,7 @@ from banjo.models import (
 
 class User(Model):
     name = StringField(unique=True)
-    public_key = StringField(unique=True)
+    public_key = StringField()
 
     def to_dict(self):
         return {
@@ -20,3 +20,10 @@ class Message(Model):
     recipient = ForeignKey(User, related_name="messages_received")
     ciphertext = StringField()
     read = BooleanField()
+
+    def to_dict(self):
+        return {
+            'sender': self.sender.name,
+            'recipient': self.recipient.name, 
+            'ciphertext': self.ciphertext,
+        }

server/app/views.py

@@ -2,7 +2,10 @@ from banjo.urls import route_get, route_post
 from app.models import User, Message
 from banjo.http import NotFound, NotAllowed
 from datetime import datetime
-import rsa
+from cryptography.exceptions import InvalidSignature
+import sys
+sys.path.insert(0, "..")
+from encryption import PrivateKey, PublicKey
 
 @route_post("users/new", args={'name': str, 'public_key': str})
 def create_user(params):
@@ -27,14 +30,14 @@ def get_user(params):
 def get_messages(params):
     "Return all the messages for a user"
     try:
-        user = User.objects.get(name=params['name'])
+        recipient = User.objects.get(name=params['name'])
     except User.DoesNotExist:
         raise NotFound(f"There is no user named {params['name']}")
-    messages = Message.objects.filter(user=user)
+    messages = Message.objects.filter(recipient=recipient)
     return {'messages': [m.to_dict() for m in messages]}
 
 @route_get("messages/send", args={'sender': str, 'recipient': str, 'ciphertext': str,
-        'time_sent': str, 'auth': str})
+        'time_sent': str, 'time_sent_signature': str})
 def send_message(params):
     """Securely sends an encrypted message from `sender` to `recipient`
     Sender and recipient should be recognized usernames. 
@@ -44,18 +47,28 @@ def send_message(params):
     """
     try:
         sender = User.objects.get(name=params['sender'])
-        recipient = User.objects.get(name=['recipient'])
+        recipient = User.objects.get(name=params['recipient'])
     except User.DoesNotExist:
-        raise NotFound(f"There is no user named {params['name']}")
+        raise NotFound(f"User not found.")
     try: 
         time_sent = datetime.fromisoformat(params['time_sent'])
     except ValueError:
         raise NotAllowed(f"Time sent ({params['time_sent']}) must be in isoformat")
-    if (datetime.now() - time_sent).seconds > 10:
+    now = datetime.utcnow()
+    if (now - time_sent).seconds > 10:
         raise NotAllowed(f"The message is too old. Time sent must be within ten seconds")
-    if not 
-
-
+    sender_public_key = PublicKey.load(sender.public_key)
+    try:
+        sender_public_key.verify_signature(params['time_sent'], params['time_sent_signature'])
+    except InvalidSignature:
+        raise NotAllowed("Invalid signature.")
+    message = Message(
+        sender=sender,
+        recipient=recipient,
+        ciphertext=params['ciphertext'],
+    )
+    message.save()
+    return message.to_dict()