the fix

src/java.base/share/classes/com/sun/crypto/provider/HKDFKeyDerivation.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2024, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2024, 2025, 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
@@ -180,8 +180,8 @@ protected byte[] engineDeriveData(AlgorithmParameterSpec derivationSpec)
         } else if (derivationSpec instanceof HKDFParameterSpec.Expand anExpand) {
             // set this value in the "if"
             if ((pseudoRandomKey = anExpand.prk().getEncoded()) == null) {
-                throw new AssertionError(
-                        "PRK is required for HKDFParameterSpec.Expand");
+                throw new InvalidAlgorithmParameterException(
+                        "Cannot retrieve PRK for HKDFParameterSpec.Expand");
             }
             // set this value in the "if"
             if ((info = anExpand.info()) == null) {
@@ -411,4 +411,4 @@ public HKDFSHA512(KDFParameters kdfParameters)
         }
     }
 
-}
+}

test/jdk/com/sun/crypto/provider/KDF/HKDFDelayedPRK.java

@@ -0,0 +1,104 @@
+/*
+ * Copyright (c) 2025, 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 8347289
+ * @summary make sure DPS works when non-extractable PRK is provided
+ * @library /test/lib /test/jdk/security/unsignedjce
+ * @build java.base/javax.crypto.ProviderVerifier
+ * @enablePreview
+ * @run main/othervm HKDFDelayedPRK
+ */
+
+import jdk.test.lib.Asserts;
+
+import javax.crypto.KDF;
+import javax.crypto.KDFParameters;
+import javax.crypto.KDFSpi;
+import javax.crypto.SecretKey;
+import javax.crypto.spec.HKDFParameterSpec;
+import javax.crypto.spec.SecretKeySpec;
+import java.security.InvalidAlgorithmParameterException;
+import java.security.Provider;
+import java.security.Security;
+import java.security.spec.AlgorithmParameterSpec;
+
+public class HKDFDelayedPRK {
+    public static void main(String[] args) throws Exception {
+        // This is a fake non-extractable key
+        var prk = new SecretKey() {
+            @Override
+            public String getAlgorithm() {
+                return "PRK";
+            }
+
+            @Override
+            public String getFormat() {
+                return null;
+            }
+
+            @Override
+            public byte[] getEncoded() {
+                return null;
+            }
+        };
+
+        Security.addProvider(new ProviderImpl());
+        var kdf = KDF.getInstance("HKDF-SHA256");
+        kdf.deriveData(HKDFParameterSpec.expandOnly(prk, null, 32));
+
+        // Confirms our own omnipotent impl is selected
+        Asserts.assertEquals("P", kdf.getProviderName());
+    }
+
+    public static class ProviderImpl extends Provider {
+        public ProviderImpl() {
+            super("P", "1", "info");
+            put("KDF.HKDF-SHA256", KDFImpl.class.getName());
+        }
+    }
+
+    // This HKDF impl accepts everything
+    public static class KDFImpl extends KDFSpi {
+
+        public KDFImpl(KDFParameters params) throws InvalidAlgorithmParameterException {
+            super(params);
+        }
+
+        @Override
+        protected KDFParameters engineGetParameters() {
+            return null;
+        }
+
+        @Override
+        protected SecretKey engineDeriveKey(String alg, AlgorithmParameterSpec dummy) {
+            return new SecretKeySpec(new byte[32], alg);
+        }
+
+        @Override
+        protected byte[] engineDeriveData(AlgorithmParameterSpec dummy) {
+            return new byte[32];
+        }
+    }
+}