Added a builder method to sign/encrypt as a text document rather than binary data (#60).

Author: bjansen

src/main/java/name/neuhalfen/projects/crypto/bouncycastle/openpgp/BuildEncryptionOutputStreamAPI.java

@@ -51,6 +51,7 @@ public final class BuildEncryptionOutputStreamAPI {
   private String signWith;
   private Set<PGPPublicKey> recipients;
   private boolean armorOutput;
+  private boolean textMode;
 
   // Signature
 
@@ -99,6 +100,16 @@ OutputStream andWriteTo(OutputStream sinkForEncryptedData)
         throws PGPException, SignatureException, NoSuchAlgorithmException, NoSuchProviderException, IOException;
   }
 
+  public interface BuildWithTextMode extends Build {
+
+    /**
+     * Emulates GnuPG's {@code --textmode} flag, which encodes data as text literal
+     * packets rather than binary literal packets.
+     * @return next step
+     */
+    Build textMode();
+  }
+
 
   public interface WithAlgorithmSuite {
 
@@ -222,14 +233,14 @@ interface Armor {
            *
            * @return next step
            */
-          Build binaryOutput();
+          BuildWithTextMode binaryOutput();
 
           /**
            * Ascii armor the output, e.g. for usage in text protocols.
            *
            * @return next step
            */
-          Build armorAsciiOutput();
+          BuildWithTextMode armorAsciiOutput();
         }
       }
     }
@@ -486,21 +497,21 @@ public Armor andDoNotSign() {
         public final class ArmorImpl implements Armor {
 
           @Override
-          public Build binaryOutput() {
+          public BuildWithTextMode binaryOutput() {
             BuildEncryptionOutputStreamAPI.this.armorOutput = false;
             LOGGER.trace("binary output");
-            return new Builder();
+            return new BuilderWithTextMode();
           }
 
           @Override
-          public Build armorAsciiOutput() {
+          public BuildWithTextMode armorAsciiOutput() {
             BuildEncryptionOutputStreamAPI.this.armorOutput = true;
             LOGGER.trace("ascii armor output");
-            return new Builder();
+            return new BuilderWithTextMode();
           }
 
 
-          public final class Builder implements Build {
+          public class Builder implements Build {
 
             @Override
             public OutputStream andWriteTo(OutputStream sinkForEncryptedData)
@@ -513,10 +524,21 @@ public OutputStream andWriteTo(OutputStream sinkForEncryptedData)
                   BuildEncryptionOutputStreamAPI.this.sinkForEncryptedData,
                   getKeySelectionStrategy(),
                   BuildEncryptionOutputStreamAPI.this.armorOutput,
-                  BuildEncryptionOutputStreamAPI.this.recipients);
+                  BuildEncryptionOutputStreamAPI.this.recipients,
+                  BuildEncryptionOutputStreamAPI.this.textMode);
 
             }
           }
+
+          public final class BuilderWithTextMode extends Builder implements BuildWithTextMode {
+
+            @Override
+            public Build textMode() {
+              BuildEncryptionOutputStreamAPI.this.textMode = true;
+              LOGGER.trace("text mode");
+              return this;
+            }
+          }
         }
       }
     }

src/main/java/name/neuhalfen/projects/crypto/bouncycastle/openpgp/encrypting/PGPEncryptingStream.java

@@ -78,6 +78,7 @@ private PGPEncryptingStream(final KeyringConfig config, final PGPAlgorithmSuite
    * @param keySelectionStrategy selection strategy
    * @param armor armor the file (true) or use binary.
    * @param encryptTo encrypt to
+   * @param textMode simulates GnuPG's {@code --textmode} flag
    *
    * @return stream where plaintext gets written into
    *
@@ -93,7 +94,8 @@ public static OutputStream create(final KeyringConfig config,
       final OutputStream cipherTextSink,
       final KeySelectionStrategy keySelectionStrategy,
       final boolean armor,
-      final Set<PGPPublicKey> encryptTo)
+      final Set<PGPPublicKey> encryptTo,
+      final boolean textMode)
       throws IOException, PGPException, NoSuchAlgorithmException, NoSuchProviderException {
 
     requireNonNull(config, "callback must not be null");
@@ -109,7 +111,7 @@ public static OutputStream create(final KeyringConfig config,
     }
 
     final PGPEncryptingStream encryptingStream = new PGPEncryptingStream(config, algorithmSuite);
-    encryptingStream.setup(cipherTextSink, signingUid, encryptTo, keySelectionStrategy, armor);
+    encryptingStream.setup(cipherTextSink, signingUid, encryptTo, keySelectionStrategy, armor, textMode);
     return encryptingStream;
   }
 
@@ -122,6 +124,7 @@ public static OutputStream create(final KeyringConfig config,
    * @param pubEncKeys the pub enc keys
    * @param keySelectionStrategy key selection strategy (for signatures)
    * @param armor if OutputStream should be "armored", that means base64 encoded
+   * @param textMode simulates GnuPG's {@code --textmode} flag
    *
    * @throws IOException Signals that an I/O exception has occurred.
    * @throws PGPException the pGP exception
@@ -134,7 +137,8 @@ private void setup(final OutputStream cipherTextSink,
       @Nullable final String signingUid,
       final Set<PGPPublicKey> pubEncKeys,
       final KeySelectionStrategy keySelectionStrategy,
-      final boolean armor) throws
+      final boolean armor,
+      final boolean textMode) throws
       IOException, PGPException {
     isDoSign = signingUid != null;
 
@@ -186,7 +190,7 @@ private void setup(final OutputStream cipherTextSink,
           new BcPGPContentSignerBuilder(pgpSec.getPublicKey().getAlgorithm(),
               algorithmSuite.getHashAlgorithmCode().getAlgorithmId()));
 
-      signatureGenerator.init(PGPSignature.BINARY_DOCUMENT, pgpPrivKey);
+      signatureGenerator.init(textMode ? PGPSignature.CANONICAL_TEXT_DOCUMENT : PGPSignature.BINARY_DOCUMENT, pgpPrivKey);
 
       final Iterator<?> userIDs = pgpSec.getPublicKey().getUserIDs();
       if (userIDs.hasNext()) {
@@ -208,7 +212,7 @@ private void setup(final OutputStream cipherTextSink,
 
     encryptionDataStreamGenerator = new PGPLiteralDataGenerator();
     encryptionDataStream = encryptionDataStreamGenerator
-        .open(compressionStream, PGPLiteralData.BINARY, "", new Date(), new byte[1 << 16]);
+        .open(compressionStream, textMode ? PGPLiteralData.TEXT : PGPLiteralData.BINARY, "", new Date(), new byte[1 << 16]);
   }
 
   @Override
@@ -268,4 +272,4 @@ public void close() throws IOException {
       isClosed = true;
     }
   }
-}
+}

src/test/java/name/neuhalfen/projects/crypto/bouncycastle/openpgp/encrypting/EncryptWithOpenPGPTestDriver.java

@@ -91,10 +91,10 @@ void encryptAndSign(final InputStream in, OutputStream out, final Set<PGPPublicK
 
     try (final OutputStream encryptionStream = PGPEncryptingStream
         .create(config, algorithmSuite, signatureUid, out, keySelectionStrategy, armor,
-            pubEncKeys)) {
+            pubEncKeys, false)) {
       Streams.pipeAll(in, encryptionStream);
       encryptionStream.flush();
     }
     out.flush();
   }
-}
+}

src/test/java/name/neuhalfen/projects/crypto/bouncycastle/openpgp/roundtrip/EncryptionDecryptionRoundtripIntegrationTest.java

@@ -11,7 +11,6 @@
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
-import java.nio.charset.StandardCharsets;
 import java.security.NoSuchAlgorithmException;
 import java.security.NoSuchProviderException;
 import java.security.SignatureException;
@@ -127,6 +126,41 @@ public void encryptAndSignBinary_thenDecryptAndVerify_yieldsOriginalPlaintext()
     assertArrayEquals(expectedPlaintext, decryptedPlaintext);
   }
 
+  @Test
+  public void encryptAndSignTextModeBinary_thenDecryptAndVerify_yieldsOriginalPlaintext()
+      throws IOException, PGPException, NoSuchAlgorithmException, NoSuchProviderException, SignatureException {
+    final byte[] expectedPlaintext = ExampleMessages.IMPORTANT_QUOTE_TEXT.getBytes("US-ASCII");
+
+    ByteArrayOutputStream cipherText = new ByteArrayOutputStream();
+
+    final OutputStream encryptionStream = BouncyGPG
+        .encryptToStream()
+        .withConfig(Configs.keyringConfigFromFilesForSender())
+        .withAlgorithms(algorithmSuite)
+        .toRecipient("recipient@example.com")
+        .andSignWith("sender@example.com")
+        .binaryOutput()
+        .textMode()
+        .andWriteTo(cipherText);
+
+    encryptionStream.write(expectedPlaintext);
+    encryptionStream.close();
+    cipherText.close();
+
+    ByteArrayInputStream cipherTextAsSource = new ByteArrayInputStream(cipherText.toByteArray());
+
+    // Decrypt
+    final InputStream decryptedPlaintextStream = BouncyGPG
+        .decryptAndVerifyStream()
+        .withConfig(Configs.keyringConfigFromResourceForRecipient())
+        .andRequireSignatureFromAllKeys("sender@example.com")
+        .fromEncryptedInputStream(cipherTextAsSource);
+
+    final byte[] decryptedPlaintext = Streams.readAll(decryptedPlaintextStream);
+
+    assertArrayEquals(expectedPlaintext, decryptedPlaintext);
+  }
+
 
   @Test
   public void encryptAndSignBinaryWithSHA256_AES256_thenDecryptAndVerify_yieldsOriginalPlaintext()