Move EncryptionPurpose to own class

pgpainless-core/src/main/java/org/pgpainless/PGPainless.java

@@ -22,6 +22,7 @@ import org.bouncycastle.openpgp.PGPException;
 import org.bouncycastle.openpgp.PGPKeyRing;
 import org.bouncycastle.openpgp.PGPSecretKeyRing;
 import org.pgpainless.algorithm.CompressionAlgorithm;
+import org.pgpainless.algorithm.EncryptionPurpose;
 import org.pgpainless.algorithm.SymmetricKeyAlgorithm;
 import org.pgpainless.decryption_verification.DecryptionBuilder;
 import org.pgpainless.decryption_verification.DecryptionStream;
@@ -71,7 +72,7 @@ public class PGPainless {
      * Create an {@link EncryptionStream}, which can be used to encrypt and/or sign data using OpenPGP.
      * This method assumes that the stream will be used to encrypt data for communication purposes.
      * If you instead want to encrypt data that will be saved on disk (eg. a backup), use
-     * {@link #encryptAndOrSign(EncryptionStream.Purpose)} and chose an appropriate purpose.
+     * {@link #encryptAndOrSign(EncryptionPurpose)} and chose an appropriate purpose.
      *
      * @return builder
      */
@@ -85,7 +86,7 @@ public class PGPainless {
      * @param purpose how will the data be used?
      * @return builder
      */
-    public static EncryptionBuilder encryptAndOrSign(EncryptionStream.Purpose purpose) {
+    public static EncryptionBuilder encryptAndOrSign(EncryptionPurpose purpose) {
         return new EncryptionBuilder(purpose);
     }
 

pgpainless-core/src/main/java/org/pgpainless/algorithm/EncryptionPurpose.java

@@ -0,0 +1,33 @@
+/*
+ * 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.algorithm;
+
+public enum EncryptionPurpose {
+    /**
+     * The stream will encrypt communication that goes over the wire.
+     * Eg. EMail, Chat...
+     */
+    COMMUNICATIONS,
+    /**
+     * The stream will encrypt data that is stored on disk.
+     * Eg. Encrypted backup...
+     */
+    STORAGE,
+    /**
+     * The stream will use keys with either flags to encrypt the data.
+     */
+    STORAGE_AND_COMMUNICATIONS
+}

pgpainless-core/src/main/java/org/pgpainless/encryption_signing/EncryptionBuilder.java

@@ -30,6 +30,7 @@ import org.bouncycastle.openpgp.PGPSecretKeyRingCollection;
 import org.pgpainless.PGPainless;
 import org.pgpainless.algorithm.CompressionAlgorithm;
 import org.pgpainless.algorithm.DocumentSignatureType;
+import org.pgpainless.algorithm.EncryptionPurpose;
 import org.pgpainless.algorithm.SymmetricKeyAlgorithm;
 import org.pgpainless.algorithm.negotiation.SymmetricKeyAlgorithmNegotiator;
 import org.pgpainless.decryption_verification.OpenPgpMetadata;
@@ -47,10 +48,10 @@ public class EncryptionBuilder implements EncryptionBuilderInterface {
     private OpenPgpMetadata.FileInfo fileInfo;
 
     public EncryptionBuilder() {
-        this.encryptionOptions = new EncryptionOptions(EncryptionStream.Purpose.COMMUNICATIONS);
+        this.encryptionOptions = new EncryptionOptions(EncryptionPurpose.COMMUNICATIONS);
     }
 
-    public EncryptionBuilder(@Nonnull EncryptionStream.Purpose purpose) {
+    public EncryptionBuilder(@Nonnull EncryptionPurpose purpose) {
         this.encryptionOptions = new EncryptionOptions(purpose);
     }
 

pgpainless-core/src/main/java/org/pgpainless/encryption_signing/EncryptionOptions.java

@@ -29,6 +29,7 @@ import org.bouncycastle.openpgp.PGPPublicKeyRing;
 import org.bouncycastle.openpgp.PGPPublicKeyRingCollection;
 import org.bouncycastle.openpgp.operator.PBEKeyEncryptionMethodGenerator;
 import org.bouncycastle.openpgp.operator.PGPKeyEncryptionMethodGenerator;
+import org.pgpainless.algorithm.EncryptionPurpose;
 import org.pgpainless.algorithm.SymmetricKeyAlgorithm;
 import org.pgpainless.implementation.ImplementationFactory;
 import org.pgpainless.key.SubkeyIdentifier;
@@ -64,7 +65,7 @@ import org.pgpainless.util.Passphrase;
  */
 public class EncryptionOptions {
 
-    private final EncryptionStream.Purpose purpose;
+    private final EncryptionPurpose purpose;
     private final Set<PGPKeyEncryptionMethodGenerator> encryptionMethods = new LinkedHashSet<>();
     private final Set<SubkeyIdentifier> encryptionKeys = new LinkedHashSet<>();
     private final Map<SubkeyIdentifier, KeyRingInfo> keyRingInfo = new HashMap<>();
@@ -78,10 +79,10 @@ public class EncryptionOptions {
      * or {@link org.pgpainless.algorithm.KeyFlag#ENCRYPT_STORAGE}.
      */
     public EncryptionOptions() {
-        this(EncryptionStream.Purpose.STORAGE_AND_COMMUNICATIONS);
+        this(EncryptionPurpose.STORAGE_AND_COMMUNICATIONS);
     }
 
-    public EncryptionOptions(EncryptionStream.Purpose purpose) {
+    public EncryptionOptions(EncryptionPurpose purpose) {
         this.purpose = purpose;
     }
 
@@ -92,7 +93,7 @@ public class EncryptionOptions {
      * @return encryption options
      */
     public static EncryptionOptions encryptCommunications() {
-        return new EncryptionOptions(EncryptionStream.Purpose.COMMUNICATIONS);
+        return new EncryptionOptions(EncryptionPurpose.COMMUNICATIONS);
     }
 
     /**
@@ -102,7 +103,7 @@ public class EncryptionOptions {
      * @return encryption options
      */
     public static EncryptionOptions encryptDataAtRest() {
-        return new EncryptionOptions(EncryptionStream.Purpose.STORAGE);
+        return new EncryptionOptions(EncryptionPurpose.STORAGE);
     }
 
     /**

pgpainless-core/src/main/java/org/pgpainless/encryption_signing/EncryptionStream.java

@@ -46,23 +46,6 @@ import org.pgpainless.util.ArmoredOutputStreamFactory;
  */
 public final class EncryptionStream extends OutputStream {
 
-    public enum Purpose {
-        /**
-         * The stream will encrypt communication that goes over the wire.
-         * Eg. EMail, Chat...
-         */
-        COMMUNICATIONS,
-        /**
-         * The stream will encrypt data that is stored on disk.
-         * Eg. Encrypted backup...
-         */
-        STORAGE,
-        /**
-         * The stream will use keys with either flags to encrypt the data.
-         */
-        STORAGE_AND_COMMUNICATIONS
-    }
-
     private static final Logger LOGGER = Logger.getLogger(EncryptionStream.class.getName());
     private static final Level LEVEL = Level.FINE;
 

pgpainless-core/src/main/java/org/pgpainless/key/info/KeyRingInfo.java

@@ -41,11 +41,11 @@ import org.bouncycastle.openpgp.PGPSecretKeyRing;
 import org.bouncycastle.openpgp.PGPSignature;
 import org.pgpainless.PGPainless;
 import org.pgpainless.algorithm.CompressionAlgorithm;
+import org.pgpainless.algorithm.EncryptionPurpose;
 import org.pgpainless.algorithm.HashAlgorithm;
 import org.pgpainless.algorithm.KeyFlag;
 import org.pgpainless.algorithm.PublicKeyAlgorithm;
 import org.pgpainless.algorithm.SymmetricKeyAlgorithm;
-import org.pgpainless.encryption_signing.EncryptionStream;
 import org.pgpainless.exception.KeyValidationException;
 import org.pgpainless.key.OpenPgpV4Fingerprint;
 import org.pgpainless.key.SubkeyIdentifier;
@@ -691,7 +691,7 @@ public class KeyRingInfo {
      * @param purpose purpose (encrypt data at rest / communications)
      * @return encryption subkeys
      */
-    public @Nonnull List<PGPPublicKey> getEncryptionSubkeys(EncryptionStream.Purpose purpose) {
+    public @Nonnull List<PGPPublicKey> getEncryptionSubkeys(EncryptionPurpose purpose) {
         Iterator<PGPPublicKey> subkeys = keys.getPublicKeys();
         List<PGPPublicKey> encryptionKeys = new ArrayList<>();
         while (subkeys.hasNext()) {
@@ -737,7 +737,7 @@ public class KeyRingInfo {
      * @param purpose encryption purpose
      * @return encryption subkeys
      */
-    public @Nonnull List<PGPPublicKey> getEncryptionSubkeys(String userId, EncryptionStream.Purpose purpose) {
+    public @Nonnull List<PGPPublicKey> getEncryptionSubkeys(String userId, EncryptionPurpose purpose) {
         if (userId != null) {
             if (!isUserIdValid(userId)) {
                 throw new KeyValidationException(userId, getLatestUserIdCertification(userId), getUserIdRevocation(userId));

pgpainless-core/src/test/java/org/pgpainless/encryption_signing/SigningTest.java

@@ -37,6 +37,7 @@ import org.junit.jupiter.params.ParameterizedTest;
 import org.junit.jupiter.params.provider.MethodSource;
 import org.pgpainless.PGPainless;
 import org.pgpainless.algorithm.DocumentSignatureType;
+import org.pgpainless.algorithm.EncryptionPurpose;
 import org.pgpainless.decryption_verification.DecryptionStream;
 import org.pgpainless.decryption_verification.OpenPgpMetadata;
 import org.pgpainless.implementation.ImplementationFactory;
@@ -64,7 +65,7 @@ public class SigningTest {
         PGPPublicKeyRingCollection keys = new PGPPublicKeyRingCollection(Arrays.asList(julietKeys, romeoKeys));
 
         ByteArrayOutputStream out = new ByteArrayOutputStream();
-        EncryptionStream encryptionStream = PGPainless.encryptAndOrSign(EncryptionStream.Purpose.STORAGE)
+        EncryptionStream encryptionStream = PGPainless.encryptAndOrSign(EncryptionPurpose.STORAGE)
                 .onOutputStream(out)
                 .toRecipients(keys)
                 .and()

pgpainless-core/src/test/java/org/pgpainless/weird_keys/TestEncryptCommsStorageFlagsDifferentiated.java

@@ -27,9 +27,9 @@ import org.bouncycastle.openpgp.PGPPublicKeyRing;
 import org.bouncycastle.openpgp.PGPSecretKeyRing;
 import org.junit.jupiter.api.Test;
 import org.pgpainless.PGPainless;
+import org.pgpainless.algorithm.EncryptionPurpose;
 import org.pgpainless.algorithm.KeyFlag;
 import org.pgpainless.encryption_signing.EncryptionBuilderInterface;
-import org.pgpainless.encryption_signing.EncryptionStream;
 import org.pgpainless.key.generation.KeySpec;
 import org.pgpainless.key.generation.type.KeyType;
 import org.pgpainless.key.generation.type.rsa.RsaLength;
@@ -52,7 +52,7 @@ public class TestEncryptCommsStorageFlagsDifferentiated {
         PGPPublicKeyRing publicKeys = KeyRingUtils.publicKeyRingFrom(secretKeys);
 
         ByteArrayOutputStream out = new ByteArrayOutputStream();
-        EncryptionBuilderInterface.ToRecipients builder = PGPainless.encryptAndOrSign(EncryptionStream.Purpose.COMMUNICATIONS)
+        EncryptionBuilderInterface.ToRecipients builder = PGPainless.encryptAndOrSign(EncryptionPurpose.COMMUNICATIONS)
                 .onOutputStream(out);
 
         // since the key does not carry the flag ENCRYPT_COMMS, it cannot be used by the stream.

pgpainless-core/src/test/java/org/pgpainless/weird_keys/TestTwoSubkeysEncryption.java

@@ -28,6 +28,7 @@ import org.bouncycastle.openpgp.PGPSecretKeyRing;
 import org.bouncycastle.util.io.Streams;
 import org.junit.jupiter.api.Test;
 import org.pgpainless.PGPainless;
+import org.pgpainless.algorithm.EncryptionPurpose;
 import org.pgpainless.encryption_signing.EncryptionOptions;
 import org.pgpainless.encryption_signing.EncryptionResult;
 import org.pgpainless.encryption_signing.EncryptionStream;
@@ -58,10 +59,10 @@ public class TestTwoSubkeysEncryption {
         PGPSecretKeyRing twoSuitableSubkeysKeyRing = WeirdKeys.getTwoCryptSubkeysKey();
         PGPPublicKeyRing publicKeys = KeyRingUtils.publicKeyRingFrom(twoSuitableSubkeysKeyRing);
         ByteArrayOutputStream out = new ByteArrayOutputStream();
-        EncryptionStream encryptionStream = PGPainless.encryptAndOrSign(EncryptionStream.Purpose.STORAGE)
+        EncryptionStream encryptionStream = PGPainless.encryptAndOrSign(EncryptionPurpose.STORAGE)
                 .onOutputStream(out)
                 .withOptions(
-                        ProducerOptions.encrypt(new EncryptionOptions(EncryptionStream.Purpose.STORAGE_AND_COMMUNICATIONS)
+                        ProducerOptions.encrypt(new EncryptionOptions(EncryptionPurpose.STORAGE_AND_COMMUNICATIONS)
                                 .addRecipient(publicKeys, EncryptionOptions.encryptToAllCapableSubkeys())
                         )
                         .setAsciiArmor(false)