Add tests for CachingSecretKeyRingProtector

pgpainless-core/src/main/java/org/pgpainless/key/protection/CachingSecretKeyRingProtector.java

@@ -41,6 +41,18 @@ public class CachingSecretKeyRingProtector implements SecretKeyRingProtector, Se
     private final SecretKeyRingProtector protector;
     private final SecretKeyPassphraseProvider provider;
 
+    public CachingSecretKeyRingProtector() {
+        this(null);
+    }
+
+    public CachingSecretKeyRingProtector(@Nullable SecretKeyPassphraseProvider missingPassphraseCallback) {
+        this(
+                new HashMap<>(),
+                KeyRingProtectionSettings.secureDefaultSettings(),
+                missingPassphraseCallback
+        );
+    }
+
     public CachingSecretKeyRingProtector(@Nonnull Map<Long, Passphrase> passphrases,
                                          @Nonnull KeyRingProtectionSettings protectionSettings,
                                          @Nullable SecretKeyPassphraseProvider missingPassphraseCallback) {

pgpainless-core/src/test/java/org/pgpainless/key/protection/CachingSecretKeyRingProtectorTest.java

@@ -0,0 +1,141 @@
+/*
+ * Copyright 2021 Paul Schaub.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.pgpainless.key.protection;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertNull;
+
+import java.security.InvalidAlgorithmParameterException;
+import java.security.NoSuchAlgorithmException;
+import java.util.Iterator;
+import java.util.Random;
+import javax.annotation.Nullable;
+
+import org.bouncycastle.openpgp.PGPException;
+import org.bouncycastle.openpgp.PGPKeyRing;
+import org.bouncycastle.openpgp.PGPPublicKey;
+import org.bouncycastle.openpgp.PGPSecretKey;
+import org.bouncycastle.openpgp.PGPSecretKeyRing;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.pgpainless.PGPainless;
+import org.pgpainless.key.protection.passphrase_provider.SecretKeyPassphraseProvider;
+import org.pgpainless.util.Passphrase;
+
+public class CachingSecretKeyRingProtectorTest {
+
+    // Dummy passphrase callback that returns the doubled key-id as passphrase
+    private final SecretKeyPassphraseProvider dummyCallback = new SecretKeyPassphraseProvider() {
+        @Nullable
+        @Override
+        public Passphrase getPassphraseFor(Long keyId) {
+            long doubled = keyId * 2;
+            return Passphrase.fromPassword(Long.toString(doubled));
+        }
+    };
+
+    private CachingSecretKeyRingProtector protector;
+
+    @BeforeEach
+    public void resetProtectors() {
+        protector = new CachingSecretKeyRingProtector();
+    }
+
+    @Test
+    public void noCallbackReturnsNullForUnknownKeyId() throws PGPException {
+        assertNull(protector.getDecryptor(123L));
+        assertNull(protector.getEncryptor(123L));
+    }
+
+    @Test
+    public void testAddPassphrase() throws PGPException {
+        Passphrase passphrase = Passphrase.fromPassword("HelloWorld");
+        protector.addPassphrase(123L, passphrase);
+        assertEquals(passphrase, protector.getPassphraseFor(123L));
+        assertNotNull(protector.getEncryptor(123L));
+        assertNotNull(protector.getDecryptor(123L));
+
+        assertNull(protector.getPassphraseFor(999L));
+    }
+
+    @Test
+    public void testForgetPassphrase() {
+        Passphrase passphrase = Passphrase.fromPassword("amnesiac");
+        protector.addPassphrase(123L, passphrase);
+        assertEquals(passphrase, protector.getPassphraseFor(123L));
+        protector.forgetPassphrase(123L);
+        assertNull(protector.getPassphraseFor(123L));
+    }
+
+    @Test
+    public void testAddPassphraseForKeyRing() throws PGPException, InvalidAlgorithmParameterException, NoSuchAlgorithmException {
+        PGPSecretKeyRing keys = PGPainless.generateKeyRing()
+                .modernKeyRing("test@test.test", "Passphrase123");
+        Passphrase passphrase = Passphrase.fromPassword("Passphrase123");
+
+        protector.addPassphrase(keys, passphrase);
+        Iterator<PGPSecretKey> it = keys.getSecretKeys();
+        while (it.hasNext()) {
+            PGPSecretKey key = it.next();
+            assertEquals(passphrase, protector.getPassphraseFor(key));
+            assertNotNull(protector.getEncryptor(key.getKeyID()));
+            assertNotNull(protector.getDecryptor(key.getKeyID()));
+        }
+
+        long nonMatching = findNonMatchingKeyId(keys);
+        assertNull(protector.getPassphraseFor(nonMatching));
+
+        protector.forgetPassphrase(keys);
+        it = keys.getSecretKeys();
+        while (it.hasNext()) {
+            PGPSecretKey key = it.next();
+            assertNull(protector.getPassphraseFor(key));
+            assertNull(protector.getEncryptor(key.getKeyID()));
+            assertNull(protector.getDecryptor(key.getKeyID()));
+        }
+    }
+
+    private static long findNonMatchingKeyId(PGPKeyRing keyRing) {
+        Random random = new Random();
+        long nonMatchingKeyId = 123L;
+        outerloop: while (true) {
+            Iterator<PGPPublicKey> pubKeys = keyRing.getPublicKeys();
+            while (pubKeys.hasNext()) {
+                if (pubKeys.next().getKeyID() == nonMatchingKeyId) {
+                    nonMatchingKeyId = random.nextLong();
+                    continue outerloop;
+                }
+            }
+            return nonMatchingKeyId;
+        }
+    }
+
+    @Test
+    public void testProtectorWithCallback() {
+        CachingSecretKeyRingProtector withCallback = new CachingSecretKeyRingProtector(dummyCallback);
+
+        for (int i = -5; i <= 5; i++) {
+            long x = i * 5;
+            long doubled = x * 2;
+
+            Passphrase passphrase = withCallback.getPassphraseFor(x);
+            assertNotNull(passphrase);
+            assertEquals(doubled, Long.valueOf(new String(passphrase.getChars())));
+        }
+    }
+
+}