Fix decrypt error with pkcs1 padding

Switched from remainder to modulo operation to always get a positive integer.
invisal · Nov 7, 2022 · 450aebc · 450aebc
1 parent 0544b74
commit 450aebc
Showing 1 changed file with 2 additions and 1 deletion.
diff --git a/src/rsa/rsa_internal.ts b/src/rsa/rsa_internal.ts
@@ -33,7 +33,8 @@ export function rsadp(key: RSAKey, c: bigint): bigint {
     if (m1 >= m2) {
       h = (key.qi * (m1 - m2)) % key.p;
     } else {
-      h = (key.qi * (m1 - m2 + key.p * (key.p / key.q))) % key.p;
+      h = ((key.qi * (m1 - m2 + key.p * (key.p / key.q))) % key.p + key.p) %
+        key.p;
     }
 
     return (m2 + h * key.q) % (key.q * key.p);