crypto: DSA parameter validation in FIPS mode

FIPS 180-4 requires specific (L,N) values. OpenSSL will crash if an invalid combination is used, so we must check the input sanity first. PR-URL: #3756 Reviewed-By: Fedor Indutny <[email protected]> Reviewed-By: Shigeki Ohtsu <[email protected]> Reviewed-By: James M Snell <[email protected]>
nodejs · Nov 17, 2015 · 7a290ab · 7a290ab
1 parent fd0253b
commit 7a290ab
Showing 1 changed file with 23 additions and 0 deletions.
diff --git a/src/node_crypto.cc b/src/node_crypto.cc
@@ -3781,6 +3781,29 @@ SignBase::Error Sign::SignFinal(const char* key_pem,
   if (pkey == nullptr || 0 != ERR_peek_error())
     goto exit;
 
+#ifdef NODE_FIPS_MODE
+  /* Validate DSA2 parameters from FIPS 186-4 */
+  if (EVP_PKEY_DSA == pkey->type) {
+    size_t L = BN_num_bits(pkey->pkey.dsa->p);
+    size_t N = BN_num_bits(pkey->pkey.dsa->q);
+    bool result = false;
+
+    if (L == 1024 && N == 160)
+      result = true;
+    else if (L == 2048 && N == 224)
+      result = true;
+    else if (L == 2048 && N == 256)
+      result = true;
+    else if (L == 3072 && N == 256)
+      result = true;
+
+    if (!result) {
+      fatal = true;
+      goto exit;
+    }
+  }
+#endif  // NODE_FIPS_MODE
+
   if (EVP_SignFinal(&mdctx_, *sig, sig_len, pkey))
     fatal = false;