Merge pull request #48 from OpenMined/pryvote_shamir_protocol

Pryvote shamir protocol

Author: wip-abramson

projects/pryvote/README.md

@@ -15,7 +15,28 @@ The project is in early development.
 
 ## Examples
 
-#### [Secure Multi-Party Voting](./demo/secure_multi_party_voting.ipynb)
+#### [Secure Multi-Party Voting](./demo/1_secure_multi_party_voting.ipynb)
 
 POC of secure multi-party voting.
-No credential verification/SSI in place at the moment.
+Each vote is encrypted and split
+between multiple vote counters.
+At the end of voting,
+the vote counters combine
+their encrypted shares
+to reveal the aggregate result.
+
+**No credential verification/SSI in place at the moment.**
+
+#### [Shamir Secret Sharing](./demo/2_shamir_secret_sharing_voting.ipynb)
+
+The Shamir Secret Sharing protocol
+is similar to SMPV,
+however only a subset of vote counters
+are required for the aggregate result
+to be decrypted.
+Therefore,
+this protocol is somewhat robust
+to malicious
+vote counters.
+
+**No credential verification/SSI in place at the moment.**

projects/pryvote/demo/secure_multi_party_voting.ipynb renamed to projects/pryvote/demo/1_secure_multi_party_voting.ipynb

@@ -36,7 +36,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 1,
    "metadata": {},
    "outputs": [],
    "source": [
@@ -57,7 +57,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 2,
    "metadata": {},
    "outputs": [],
    "source": [
@@ -82,7 +82,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 3,
    "metadata": {},
    "outputs": [],
    "source": [
@@ -109,7 +109,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 4,
    "metadata": {},
    "outputs": [],
    "source": [
@@ -124,7 +124,7 @@
     "            vote_class = pricon_vote.get_vote_class(vote_value)\n",
     "\n",
     "            onehot_votes = [0] * len(pricon_vote)\n",
-    "            onehot_votes[vote_class] = 1\n",
+    "            onehot_votes[vote_class] = 1  # [1, 0, 0]\n",
     "            \n",
     "            vote_shares = [self._encrypt_vote(binary_vote) for binary_vote in onehot_votes]\n",
     "\n",
@@ -134,9 +134,9 @@
     "            self._vote_shares = None\n",
     "\n",
     "    def _encrypt_vote(self, vote: int):\n",
-    "        share_a = random.randint(-Q,Q)\n",
-    "        share_b = random.randint(-Q,Q)\n",
-    "        share_c = (vote - share_a - share_b) % Q\n",
+    "        share_a = random.randint(-self._Q,self._Q)\n",
+    "        share_b = random.randint(-self._Q,self._Q)\n",
+    "        share_c = (vote - share_a - share_b) % self._Q\n",
     "        return (share_a, share_b,  share_c)\n",
     "\n",
     "    def send_vote(self, parties) -> None:\n",
@@ -152,7 +152,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 5,
    "metadata": {},
    "outputs": [],
    "source": [
@@ -183,7 +183,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 6,
    "metadata": {},
    "outputs": [],
    "source": [
@@ -201,7 +201,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 7,
    "metadata": {},
    "outputs": [],
    "source": [
@@ -212,7 +212,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 8,
    "metadata": {},
    "outputs": [],
    "source": [
@@ -244,7 +244,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 9,
    "metadata": {},
    "outputs": [],
    "source": [
@@ -254,19 +254,74 @@
     "dan.update_vote(\"PryVote\")\n",
     "eve.update_vote(\"PyDP\")\n",
     "fran.update_vote(\"PyVertical\")\n",
-    "greg.update_vote(\"PrivacyRaven\")"
+    "greg.update_vote(\"PyVertical\")"
    ]
   },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 10,
    "metadata": {},
-   "outputs": [],
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "red: Adding vote for 3a29334a-cff6-4a73-b681-29aa0bd3be41\n",
+      "blue: Adding vote for 3a29334a-cff6-4a73-b681-29aa0bd3be41\n",
+      "yellow: Adding vote for 3a29334a-cff6-4a73-b681-29aa0bd3be41\n",
+      "red: Adding vote for c33db94b-8e5b-488f-ac39-91c74491f123\n",
+      "blue: Adding vote for c33db94b-8e5b-488f-ac39-91c74491f123\n",
+      "yellow: Adding vote for c33db94b-8e5b-488f-ac39-91c74491f123\n",
+      "red: Adding vote for 0347145d-dd85-4ef8-930f-12dcff90190e\n",
+      "blue: Adding vote for 0347145d-dd85-4ef8-930f-12dcff90190e\n",
+      "yellow: Adding vote for 0347145d-dd85-4ef8-930f-12dcff90190e\n",
+      "red: Adding vote for 5d88aa47-a73a-4e04-9111-fa0f0fef189d\n",
+      "blue: Adding vote for 5d88aa47-a73a-4e04-9111-fa0f0fef189d\n",
+      "yellow: Adding vote for 5d88aa47-a73a-4e04-9111-fa0f0fef189d\n",
+      "red: Adding vote for 7e41730d-4270-490f-b227-a3ee719373eb\n",
+      "blue: Adding vote for 7e41730d-4270-490f-b227-a3ee719373eb\n",
+      "yellow: Adding vote for 7e41730d-4270-490f-b227-a3ee719373eb\n",
+      "red: Adding vote for eb09cd17-166f-4fa4-8a89-ac7a199119e3\n",
+      "blue: Adding vote for eb09cd17-166f-4fa4-8a89-ac7a199119e3\n",
+      "yellow: Adding vote for eb09cd17-166f-4fa4-8a89-ac7a199119e3\n",
+      "red: Adding vote for fd992cfa-bb52-4fdd-b42f-90c2b1107ac4\n",
+      "blue: Adding vote for fd992cfa-bb52-4fdd-b42f-90c2b1107ac4\n",
+      "yellow: Adding vote for fd992cfa-bb52-4fdd-b42f-90c2b1107ac4\n"
+     ]
+    }
+   ],
    "source": [
     "for voter in [alice, bob, charlie, dan, eve, fran, greg]:\n",
     "    voter.send_vote([red, blue, yellow])"
    ]
   },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "What do the votes look like to a vote counter?"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 11,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "[-1689120296584, -1384865635954, -859978157999]"
+      ]
+     },
+     "execution_count": 11,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "red._vote_sum"
+   ]
+  },
   {
    "cell_type": "markdown",
    "metadata": {},
@@ -287,9 +342,18 @@
   },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 12,
    "metadata": {},
-   "outputs": [],
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Vote counts are [3, 2, 2]\n",
+      "PryVote is the winner!\n"
+     ]
+    }
+   ],
    "source": [
     "total_sums = []\n",
     "\n",
@@ -344,6 +408,27 @@
     "This could be solved by policy,\n",
     "such as frequent, independent auditing of a running vote aggregation during the lifetime of a vote session."
    ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": []
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": []
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": []
   }
  ],
  "metadata": {
@@ -362,7 +447,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.8.5"
+   "version": "3.7.9"
   }
  },
  "nbformat": 4,