Make Key and Certificate extend KeyMaterial,

get rid of CertificateReader

pgp-cert-d-java/src/main/java/pgp/cert_d/BackendProvider.java

@@ -4,14 +4,11 @@
 
 package pgp.cert_d;
 
-import pgp.certificate_store.CertificateReaderBackend;
 import pgp.certificate_store.CertificateMerger;
 import pgp.certificate_store.KeyReaderBackend;
 
 public abstract class BackendProvider {
 
-    public abstract CertificateReaderBackend provideCertificateReaderBackend();
-
     public abstract KeyReaderBackend provideKeyReaderBackend();
 
     public abstract CertificateMerger provideDefaultMergeCallback();

pgp-cert-d-java/src/main/java/pgp/cert_d/SharedPGPCertificateDirectoryImpl.java

@@ -17,54 +17,47 @@ import java.util.Iterator;
 import java.util.List;
 
 import pgp.certificate_store.Key;
+import pgp.certificate_store.KeyMaterial;
 import pgp.certificate_store.KeyMerger;
 import pgp.certificate_store.KeyReaderBackend;
 import pgp.certificate_store.exception.BadDataException;
 import pgp.certificate_store.exception.BadNameException;
 import pgp.certificate_store.exception.NotAStoreException;
 import pgp.certificate_store.Certificate;
-import pgp.certificate_store.CertificateReaderBackend;
 import pgp.certificate_store.CertificateMerger;
 
 public class SharedPGPCertificateDirectoryImpl implements SharedPGPCertificateDirectory {
 
     private final FilenameResolver resolver;
     private final LockingMechanism writeLock;
-    private final CertificateReaderBackend certificateReaderBackend;
     private final KeyReaderBackend keyReaderBackend;
 
     public SharedPGPCertificateDirectoryImpl(BackendProvider backendProvider)
             throws NotAStoreException {
-        this(backendProvider.provideCertificateReaderBackend(), backendProvider.provideKeyReaderBackend());
+        this(backendProvider.provideKeyReaderBackend());
     }
 
-    public SharedPGPCertificateDirectoryImpl(CertificateReaderBackend certificateReaderBackend,
+    public SharedPGPCertificateDirectoryImpl(KeyReaderBackend keyReaderBackend)
-                                             KeyReaderBackend keyReaderBackend)
             throws NotAStoreException {
         this(
                 BaseDirectoryProvider.getDefaultBaseDir(),
-                certificateReaderBackend,
                 keyReaderBackend);
     }
 
     public SharedPGPCertificateDirectoryImpl(File baseDirectory,
-                                             CertificateReaderBackend certificateReaderBackend,
                                              KeyReaderBackend keyReaderBackend)
             throws NotAStoreException {
         this(
-                certificateReaderBackend,
                 keyReaderBackend,
                 new FilenameResolver(baseDirectory),
                 FileLockingMechanism.defaultDirectoryFileLock(baseDirectory));
     }
 
     public SharedPGPCertificateDirectoryImpl(
-            CertificateReaderBackend certificateReaderBackend,
             KeyReaderBackend keyReaderBackend,
             FilenameResolver filenameResolver,
             LockingMechanism writeLock)
             throws NotAStoreException {
-        this.certificateReaderBackend = certificateReaderBackend;
         this.keyReaderBackend = keyReaderBackend;
         this.resolver = filenameResolver;
         this.writeLock = writeLock;
@@ -96,8 +89,8 @@ public class SharedPGPCertificateDirectoryImpl implements SharedPGPCertificateDi
 
         FileInputStream fileIn = new FileInputStream(certFile);
         BufferedInputStream bufferedIn = new BufferedInputStream(fileIn);
-        Certificate certificate = certificateReaderBackend.readCertificate(bufferedIn);
 
+        Certificate certificate = readCertificate(bufferedIn);
         if (!certificate.getFingerprint().equals(fingerprint)) {
             // TODO: Figure out more suitable exception
             throw new BadDataException();
@@ -106,6 +99,28 @@ public class SharedPGPCertificateDirectoryImpl implements SharedPGPCertificateDi
         return certificate;
     }
 
+    private Certificate readCertificate(InputStream inputStream) throws BadDataException, IOException {
+        KeyMaterial record = keyReaderBackend.read(inputStream);
+        Certificate certificate = null;
+        if (record instanceof Certificate) {
+            certificate = (Certificate) record;
+        } else if (record instanceof Key) {
+            Key key = (Key) record;
+            certificate = key.getCertificate();
+        } else {
+            throw new BadDataException();
+        }
+        return certificate;
+    }
+
+    private Key readKey(InputStream inputStream) throws BadDataException, IOException {
+        KeyMaterial record = keyReaderBackend.read(inputStream);
+        if (record instanceof Key) {
+            return (Key) record;
+        }
+        throw new BadDataException();
+    }
+
     @Override
     public Certificate getBySpecialName(String specialName)
             throws IOException, BadNameException, BadDataException {
@@ -116,7 +131,7 @@ public class SharedPGPCertificateDirectoryImpl implements SharedPGPCertificateDi
 
         FileInputStream fileIn = new FileInputStream(certFile);
         BufferedInputStream bufferedIn = new BufferedInputStream(fileIn);
-        Certificate certificate = certificateReaderBackend.readCertificate(bufferedIn);
+        Certificate certificate = readCertificate(bufferedIn);
 
         return certificate;
     }
@@ -155,7 +170,7 @@ public class SharedPGPCertificateDirectoryImpl implements SharedPGPCertificateDi
         }
         FileInputStream fileIn = new FileInputStream(keyFile);
         BufferedInputStream bufferedInputStream = new BufferedInputStream(fileIn);
-        Key key = keyReaderBackend.readKey(bufferedInputStream);
+        Key key = readKey(bufferedInputStream);
 
         return key;
     }
@@ -197,7 +212,7 @@ public class SharedPGPCertificateDirectoryImpl implements SharedPGPCertificateDi
 
     private Certificate _insert(InputStream data, CertificateMerger merge)
             throws IOException, BadDataException {
-        Certificate newCertificate = certificateReaderBackend.readCertificate(data);
+        Certificate newCertificate = readCertificate(data);
         Certificate existingCertificate;
         File certFile;
         try {
@@ -218,7 +233,7 @@ public class SharedPGPCertificateDirectoryImpl implements SharedPGPCertificateDi
 
     private Key _insertTrustRoot(InputStream data, KeyMerger merge)
         throws IOException, BadDataException {
-        Key newKey = keyReaderBackend.readKey(data);
+        Key newKey = readKey(data);
         Key existingKey;
         File keyFile;
         try {
@@ -297,7 +312,7 @@ public class SharedPGPCertificateDirectoryImpl implements SharedPGPCertificateDi
 
     private Certificate _insertSpecial(String specialName, InputStream data, CertificateMerger merge)
             throws IOException, BadNameException, BadDataException {
-        Certificate newCertificate = certificateReaderBackend.readCertificate(data);
+        Certificate newCertificate = readCertificate(data);
         Certificate existingCertificate = getBySpecialName(specialName);
         File certFile = resolver.getCertFileBySpecialName(specialName);
 
@@ -338,7 +353,7 @@ public class SharedPGPCertificateDirectoryImpl implements SharedPGPCertificateDi
                             @Override
                             Certificate get() throws BadDataException {
                                 try {
-                                    Certificate certificate = certificateReaderBackend.readCertificate(new FileInputStream(certFile));
+                                    Certificate certificate = readCertificate(new FileInputStream(certFile));
                                     if (!(subdirectory.getName() + certFile.getName()).equals(certificate.getFingerprint())) {
                                         throw new BadDataException();
                                     }

pgp-certificate-store/src/main/java/pgp/certificate_store/Certificate.java

@@ -11,14 +11,7 @@ import java.util.Set;
 /**
  * OpenPGP certificate (public key).
  */
-public abstract class Certificate {
+public abstract class Certificate implements KeyMaterial {
-    /**
-     * Return the fingerprint of the certificate as 40 lowercase hex characters.
-     * TODO: Allow OpenPGP V5 fingerprints
-     *
-     * @return fingerprint
-     */
-    public abstract String getFingerprint();
 
     /**
      * Return an {@link InputStream} of the binary representation of the certificate.

pgp-certificate-store/src/main/java/pgp/certificate_store/CertificateReaderBackend.java

@@ -1,29 +0,0 @@
-// SPDX-FileCopyrightText: 2022 Paul Schaub <vanitasvitae@fsfe.org>
-//
-// SPDX-License-Identifier: Apache-2.0
-
-package pgp.certificate_store;
-
-import pgp.certificate_store.exception.BadDataException;
-
-import java.io.IOException;
-import java.io.InputStream;
-
-/**
- * Interface definition for a class that can read {@link Certificate Certificates} from binary
- * {@link InputStream InputStreams}.
- */
-public interface CertificateReaderBackend {
-
-    /**
-     * Read a {@link Certificate} from the given {@link InputStream}.
-     *
-     * @param inputStream input stream containing the binary representation of the certificate.
-     * @return certificate object
-     *
-     * @throws IOException in case of an IO error
-     * @throws BadDataException in case that the input stream does not contain OpenPGP certificate data
-     */
-    Certificate readCertificate(InputStream inputStream) throws IOException, BadDataException;
-
-}

pgp-certificate-store/src/main/java/pgp/certificate_store/Key.java

@@ -10,7 +10,7 @@ import java.io.InputStream;
 /**
  * OpenPGP key (secret key).
  */
-public abstract class Key {
+public abstract class Key implements KeyMaterial {
 
     /**
      * Return the certificate part of this OpenPGP key.

pgp-certificate-store/src/main/java/pgp/certificate_store/KeyMaterial.java

@@ -0,0 +1,17 @@
+// SPDX-FileCopyrightText: 2022 Paul Schaub <vanitasvitae@fsfe.org>
+//
+// SPDX-License-Identifier: Apache-2.0
+
+package pgp.certificate_store;
+
+public interface KeyMaterial {
+
+    /**
+     * Return the fingerprint of the certificate as 40 lowercase hex characters.
+     * TODO: Allow OpenPGP V5 fingerprints
+     *
+     * @return fingerprint
+     */
+    String getFingerprint();
+
+}

pgp-certificate-store/src/main/java/pgp/certificate_store/KeyReaderBackend.java

@@ -12,13 +12,13 @@ import java.io.InputStream;
 public interface KeyReaderBackend {
 
     /**
-     * Read a {@link Key} from the given {@link InputStream}.
+     * Read a {@link KeyMaterial} (either {@link Key} or {@link Certificate}) from the given {@link InputStream}.
      *
      * @param data input stream containing the binary representation of the key.
-     * @return key object
+     * @return key or certificate object
      *
      * @throws IOException in case of an IO error
-     * @throws BadDataException in case that the data stream does not contain a valid OpenPGP key
+     * @throws BadDataException in case that the data stream does not contain a valid OpenPGP key/certificate
      */
-    Key readKey(InputStream data) throws IOException, BadDataException;
+    KeyMaterial read(InputStream data) throws IOException, BadDataException;
 }