From d265ce91d3b199e0a8f35dd4ac0a9958a2bb837a Mon Sep 17 00:00:00 2001
From: Qudsia tariw <tariq.qudsia18@gmail.com>
Date: Tue, 25 Feb 2025 13:23:55 +0500
Subject: [PATCH] removed randomness. fixed a bug with receipt view after
 elections end

---
 app/actions/elections_actions.py        |  2 +-
 app/encryption.py                       | 20 +++++-------
 app/templates/app/elections/detail.html | 42 ++++++++++++++-----------
 3 files changed, 32 insertions(+), 32 deletions(-)

diff --git a/app/actions/elections_actions.py b/app/actions/elections_actions.py
index 58efb75..55a2884 100644
--- a/app/actions/elections_actions.py
+++ b/app/actions/elections_actions.py
@@ -59,7 +59,7 @@ def end_election(modeladmin, request, queryset):
             for i in range(len(votes)):
                 ballot = json.loads(votes[i].ballot)
                 for j in range(len(ballot)):
-                    json_str_positive = json.dumps({'ciphertext': ballot[j], 'randomness': None})
+                    json_str_positive = json.dumps({'ciphertext': ballot[j]})
                     ct_temp_positive = Ciphertext.from_json(json_str_positive)
                     if i == 0:
                         encrypted_positive_total[j] = ct_temp_positive    
diff --git a/app/encryption.py b/app/encryption.py
index 05581b2..25c493b 100644
--- a/app/encryption.py
+++ b/app/encryption.py
@@ -4,29 +4,26 @@
 import json
 
 class Ciphertext:
-    def __init__(self, ciphertext: int, randomness: int = None):
+    def __init__(self, ciphertext: int):
         """
         Initialize a Ciphertext object.
         
         :param ciphertext: The encrypted value
-        :param randomness: The randomness used in encryption (optional)
         """
         self.ciphertext = ciphertext
-        self.randomness = randomness
 
     def __repr__(self):
         """
         Provide a string representation of the CipherData object for debugging.
         """
-        return f"CipherData(ciphertext='{self.ciphertext}', randomness='{self.randomness}')"
+        return f"CipherData(ciphertext='{self.ciphertext}')"
 
     def to_json(self):
         """
         Convert the ciphertext object to JSON format.
         """
         return json.dumps({
-            'ciphertext': str(self.ciphertext),
-            'randomness': str(self.randomness) if self.randomness else None
+            'ciphertext': str(self.ciphertext)
         })
 
     @classmethod
@@ -35,7 +32,7 @@ def from_json(cls, json_str):
         Create a Ciphertext object from JSON string.
         """
         data = json.loads(json_str)
-        return cls(int(data['ciphertext']), int(data['randomness']) if data['randomness'] else None)
+        return cls(int(data['ciphertext']))
 
 class Encryption:
     def __init__(self, public_key: str = None, private_key: str = None):
@@ -46,7 +43,7 @@ def __init__(self, public_key: str = None, private_key: str = None):
         :param private_key: The private key phi value
         """
         if public_key is None and private_key is None:
-            self.paillier = Paillier()
+            self.paillier = Paillier(key_size=2048)
         elif public_key is not None and private_key is None:
             public_key_g, public_key_n = map(int, public_key.split(','))
             keys = {"public_key": {"g": public_key_g, "n": public_key_n}}
@@ -77,7 +74,7 @@ def encrypt(self, plaintext: int, rand: int = None) -> Ciphertext:
         if rand is None:
             rand = self.generate_random_key()
         ct = self.paillier.encrypt(plaintext, rand)
-        return Ciphertext(ct, rand)
+        return Ciphertext(ct)
 
     def add(self, ct1: Ciphertext, ct2: Ciphertext) -> Ciphertext:
         """
@@ -88,10 +85,7 @@ def add(self, ct1: Ciphertext, ct2: Ciphertext) -> Ciphertext:
         :return: Ciphertext object containing encrypted sum
         """
         sum_ct = self.paillier.add(ct1.ciphertext, ct2.ciphertext)
-        combined_randomness = None
-        if ct1.randomness and ct2.randomness:
-            combined_randomness = (ct1.randomness * ct2.randomness) % self.paillier.ciphertext_modulo
-        return Ciphertext(sum_ct, combined_randomness)
+        return Ciphertext(sum_ct)
     
     def decrypt(self, ct: Ciphertext) -> int:
         """
diff --git a/app/templates/app/elections/detail.html b/app/templates/app/elections/detail.html
index f2f0297..e53f840 100644
--- a/app/templates/app/elections/detail.html
+++ b/app/templates/app/elections/detail.html
@@ -7,36 +7,42 @@ <h1>{{ election.name }}</h1>
 </header>
 
 {% if election.active %}
-  <p>{{ election.votes.count }} votes</p>
+<p>{{ election.votes.count }} votes</p>
 {% endif %}
 
 {% if voted %}
-  <p>You have already voted in this election.</p>
-  <p><b>Vote details:</b></p>
-  <p>Hash: {{ receipt.hashed }}</p>
-  <p>Date: {{ receipt.created }}</p>
+<p>You have already voted in this election.</p>
+<p><b>Vote details:</b></p>
+<p>Hash: {{ receipt.hashed }}</p>
+<p>Date: {{ receipt.created }}</p>
 
 {% else %}
-  <div class="row">
+
+{% if election.active %}
+
+<div class="row">
   {% for candidate in election.candidates.all %}
-    <div class="col-md-4">
-      <div class="card card-body">
-        <h2>{{ candidate.user.get_username }}</h2>
-        <p class="mb-0"><a class="btn btn-primary" href="{% url 'vote' election.id candidate.id %}">VOTE</a></p>
-      </div>
+  <div class="col-md-4">
+    <div class="card card-body">
+      <h2>{{ candidate.user.get_username }}</h2>
+      <p class="mb-0"><a class="btn btn-primary" href="{% url 'vote' election.id candidate.id %}">VOTE</a></p>
     </div>
+  </div>
   {% endfor %}
 </div>
 
 {% endif %}
+{% endif %}
+
 {% if not election.active %}
-  <div class="row">
-    <div class="col-md-12">
-      <h2>Election Results</h2>
-      <p>Decrypted Total: {{ election.decrypted_total }}</p>
-      <button class="btn btn-primary" hx-get="{% url 'verify_results' election.id %}" hx-target="#results">Verify Results</button>
-      <div id="results"></div>
-    </div>
+<div class="row">
+  <div class="col-md-12">
+    <h2>Election Results</h2>
+    <p>Decrypted Total: {{ election.decrypted_total }}</p>
+    <button class="btn btn-primary" hx-get="{% url 'verify_results' election.id %}" hx-target="#results">Verify
+      Results</button>
+    <div id="results"></div>
   </div>
+</div>
 {% endif %}
 {% endblock %}
\ No newline at end of file