8373690: Unexpected Keystore message using jdk.crypto.disabledAlgorithms

Reviewed-by: mullan, coffeys

src/java.base/share/classes/java/security/KeyStore.java

@@ -1870,6 +1870,7 @@ public class KeyStore {
         }
 
         KeyStore keystore = null;
+        String matched = null;
 
         try (DataInputStream dataStream =
             new DataInputStream(
@@ -1893,8 +1894,10 @@ public class KeyStore {
                                 if (CryptoAlgorithmConstraints.permits(
                                         "KEYSTORE", ksAlgo)) {
                                     keystore = new KeyStore(impl, p, ksAlgo);
-                                    break;
+                                } else {
+                                    matched = ksAlgo;
                                 }
+                                break;
                             }
                         } catch (NoSuchAlgorithmException e) {
                             // ignore
@@ -1924,9 +1927,14 @@ public class KeyStore {
                 return keystore;
             }
         }
-
-        throw new KeyStoreException("Unrecognized keystore format. "
-                + "Please load it with a specified type");
+        if (matched == null) {
+            throw new KeyStoreException("Unrecognized keystore format. "
+                    + "Please load it with a specified type");
+        } else {
+            throw new KeyStoreException("Keystore format " +
+                    matched +
+                    " disabled by jdk.crypto.disabledAlgorithms property");
+        }
     }
 
     /**

test/jdk/java/security/KeyStore/DisabledKnownType.java

@@ -0,0 +1,53 @@
+/*
+ * Copyright (c) 2026, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/**
+ * @test
+ * @bug 8373690
+ * @summary verify that the exception message indicates the keystore type
+ *         when the type is disabled instead of being unrecognized
+ * @run main/othervm -Djdk.crypto.disabledAlgorithms=KeyStore.PKCS12 DisabledKnownType
+ */
+
+import java.security.KeyStore;
+import java.security.KeyStoreException;
+
+public class DisabledKnownType {
+    public static void main(String[] args) throws Exception {
+        String cacertsPath = System.getProperty("java.home") +
+                "/lib/security/cacerts";
+        try {
+            KeyStore ks = KeyStore.getInstance(new java.io.File(cacertsPath),
+                    "changeit".toCharArray());
+            throw new RuntimeException("Expected KeyStoreException not thrown");
+        } catch (KeyStoreException kse) {
+            if (kse.getMessage().contains("PKCS12")) {
+                System.out.println("Passed: expected ex thrown: " + kse);
+            } else {
+                // pass it up
+                throw kse;
+            }
+        }
+    }
+}
+