...

static/js/modules/crypto/paillier.js

@@ -1,4 +1,9 @@
-import { cryptoRandom, generate_prime, KEY_SIZE } from "./random_primes.js";
+import {
+    cryptoRandom,
+    generate_prime,
+    generate_safe_prime,
+    KEY_SIZE,
+} from "./random_primes.js";
 import { gcd, mod_exp } from "./math.js";
 
 const PAILLIER = 0;
@@ -371,25 +376,8 @@ export function generate_keypair() {
         p = BigInt(window.sessionStorage.getItem("p"));
         q = BigInt(window.sessionStorage.getItem("q"));
     } else {
-        let p1 = generate_prime();
-        while (p1 % 4n !== 3n) {
-            p1 = generate_prime();
-        }
-
-        let primes = [p1];
-
-        while (
-            check_gcd(primes.slice(0, primes.length - 1), primes[primes.length - 1]) ===
-            null
-        ) {
-            q = generate_prime();
-            while (q % 4n !== 3n) {
-                q = generate_prime();
-            }
-            primes.push(q);
-        }
-
-        p = check_gcd(primes.slice(0, primes.length - 1), primes[primes.length - 1]);
+        p = generate_safe_prime();
+        q = generate_safe_prime();
     }
 
     window.sessionStorage.setItem("p", p);

static/js/modules/crypto/random_primes.js

@@ -97,6 +97,15 @@ export function generate_prime() {
     }
 }
 
+export function generate_safe_prime() {
+    while (true) {
+        let n = generate_prime();
+        if (small_prime_test((n - 1n) / 2n) && miller_rabin((n - 1n) / 2n, 40)) {
+            return n;
+        }
+    }
+}
+
 const SMALL_PRIMES = [
     2n,
     3n,