Identify custom decryptor factories by subkey id

pgpainless-core/src/main/java/org/pgpainless/decryption_verification/ConsumerOptions.java

@@ -25,6 +25,7 @@ import org.bouncycastle.openpgp.PGPSignature;
 import org.bouncycastle.openpgp.operator.PublicKeyDataDecryptorFactory;
 import org.pgpainless.decryption_verification.cleartext_signatures.InMemoryMultiPassStrategy;
 import org.pgpainless.decryption_verification.cleartext_signatures.MultiPassStrategy;
+import org.pgpainless.key.SubkeyIdentifier;
 import org.pgpainless.key.protection.SecretKeyRingProtector;
 import org.pgpainless.signature.SignatureUtils;
 import org.pgpainless.util.Passphrase;
@@ -49,7 +50,7 @@ public class ConsumerOptions {
 
     // Session key for decryption without passphrase/key
     private SessionKey sessionKey = null;
-    private final Map<Long, PublicKeyDataDecryptorFactory> customPublicKeyDataDecryptorFactories = new HashMap<>();
+    private final Map<SubkeyIdentifier, PublicKeyDataDecryptorFactory> customPublicKeyDataDecryptorFactories = new HashMap<>();
 
     private final Map<PGPSecretKeyRing, SecretKeyRingProtector> decryptionKeys = new HashMap<>();
     private final Set<Passphrase> decryptionPassphrases = new HashSet<>();
@@ -249,11 +250,11 @@ public class ConsumerOptions {
      * @return options
      */
     public ConsumerOptions addCustomDecryptorFactory(@Nonnull CustomPublicKeyDataDecryptorFactory factory) {
-        this.customPublicKeyDataDecryptorFactories.put(factory.getKeyId(), factory);
+        this.customPublicKeyDataDecryptorFactories.put(factory.getSubkeyIdentifier(), factory);
         return this;
     }
 
-    Map<Long, PublicKeyDataDecryptorFactory> getCustomDecryptorFactories() {
+    Map<SubkeyIdentifier, PublicKeyDataDecryptorFactory> getCustomDecryptorFactories() {
         return new HashMap<>(customPublicKeyDataDecryptorFactories);
     }
 

pgpainless-core/src/main/java/org/pgpainless/decryption_verification/CustomPublicKeyDataDecryptorFactory.java

@@ -5,9 +5,10 @@
 package org.pgpainless.decryption_verification;
 
 import org.bouncycastle.openpgp.operator.PublicKeyDataDecryptorFactory;
+import org.pgpainless.key.SubkeyIdentifier;
 
 public interface CustomPublicKeyDataDecryptorFactory extends PublicKeyDataDecryptorFactory {
 
-    long getKeyId();
+    SubkeyIdentifier getSubkeyIdentifier();
 
 }

pgpainless-core/src/main/java/org/pgpainless/decryption_verification/DecryptionStreamFactory.java

@@ -409,7 +409,7 @@ public final class DecryptionStreamFactory {
         }
 
         // Try custom PublicKeyDataDecryptorFactories (e.g. hardware-backed).
-        Map<Long, PublicKeyDataDecryptorFactory> customFactories = options.getCustomDecryptorFactories();
+        Map<SubkeyIdentifier, PublicKeyDataDecryptorFactory> customFactories = options.getCustomDecryptorFactories();
         for (PGPPublicKeyEncryptedData publicKeyEncryptedData : publicKeyProtected) {
             Long keyId = publicKeyEncryptedData.getKeyID();
             if (!customFactories.containsKey(keyId)) {

pgpainless-core/src/main/java/org/pgpainless/decryption_verification/HardwareSecurity.java

@@ -11,6 +11,7 @@ import org.bouncycastle.openpgp.PGPSecretKeyRing;
 import org.bouncycastle.openpgp.operator.PGPDataDecryptor;
 import org.bouncycastle.openpgp.operator.PublicKeyDataDecryptorFactory;
 import org.bouncycastle.openpgp.operator.bc.BcPublicKeyDataDecryptorFactory;
+import org.pgpainless.key.SubkeyIdentifier;
 
 import java.util.HashSet;
 import java.util.Set;
@@ -74,16 +75,16 @@ public class HardwareSecurity {
         // luckily we can instantiate the BcPublicKeyDataDecryptorFactory with null as argument.
         private final PublicKeyDataDecryptorFactory factory =
                 new BcPublicKeyDataDecryptorFactory(null);
-        private long keyId;
+        private SubkeyIdentifier subkey;
 
         /**
          * Create a new {@link HardwareDataDecryptorFactory}.
          *
          * @param callback decryption callback
          */
-        public HardwareDataDecryptorFactory(long keyId, DecryptionCallback callback) {
+        public HardwareDataDecryptorFactory(SubkeyIdentifier subkeyIdentifier, DecryptionCallback callback) {
             this.callback = callback;
-            this.keyId = keyId;
+            this.subkey = subkeyIdentifier;
         }
 
         @Override
@@ -91,7 +92,7 @@ public class HardwareSecurity {
                 throws PGPException {
             try {
                 // delegate decryption to the callback
-                return callback.decryptSessionKey(keyId, keyAlgorithm, secKeyData[0]);
+                return callback.decryptSessionKey(subkey.getSubkeyId(), keyAlgorithm, secKeyData[0]);
             } catch (HardwareSecurityException e) {
                 throw new PGPException("Hardware-backed decryption failed.", e);
             }
@@ -104,8 +105,14 @@ public class HardwareSecurity {
         }
 
         @Override
-        public long getKeyId() {
+        public PGPDataDecryptor createDataDecryptor(int aeadAlgorithm, byte[] iv, int chunkSize, int encAlgorithm, byte[] key)
-            return keyId;
+                throws PGPException {
+            return factory.createDataDecryptor(aeadAlgorithm, iv, chunkSize, encAlgorithm, key);
+        }
+
+        @Override
+        public SubkeyIdentifier getSubkeyIdentifier() {
+            return subkey;
         }
     }
 

pgpainless-core/src/test/java/org/pgpainless/decryption_verification/CustomPublicKeyDataDecryptorFactoryTest.java

@@ -19,6 +19,7 @@ import org.pgpainless.algorithm.EncryptionPurpose;
 import org.pgpainless.encryption_signing.EncryptionOptions;
 import org.pgpainless.encryption_signing.EncryptionStream;
 import org.pgpainless.encryption_signing.ProducerOptions;
+import org.pgpainless.key.SubkeyIdentifier;
 import org.pgpainless.key.info.KeyRingInfo;
 import org.pgpainless.key.protection.UnlockSecretKey;
 import org.pgpainless.util.Passphrase;
@@ -74,7 +75,7 @@ public class CustomPublicKeyDataDecryptorFactoryTest {
                 .withOptions(ConsumerOptions.get()
                         .addCustomDecryptorFactory(
                                 new HardwareSecurity.HardwareDataDecryptorFactory(
-                                        encryptionKey.getKeyID(),
+                                        new SubkeyIdentifier(cert, encryptionKey.getKeyID()),
                                         hardwareDecryptionCallback)));
 
         ByteArrayOutputStream decryptedOut = new ByteArrayOutputStream();