Skip signature verification if it is not going to be displayed anyways

This also removes replacement of clearsigned data with its content from
MessageCryptoHelper, to be moved to text extraction later on.

k9mail/src/main/java/com/fsck/k9/activity/MessageLoaderHelper.java

@@ -81,6 +81,7 @@ public class MessageLoaderHelper {
     private LoaderManager loaderManager;
     @Nullable // make this explicitly nullable, make sure to cancel/ignore any operation if this is null
     private MessageLoaderCallbacks callback;
+    private final boolean processSignedOnly;
 
 
     // transient state
@@ -100,6 +101,8 @@ public class MessageLoaderHelper {
         this.loaderManager = loaderManager;
         this.fragmentManager = fragmentManager;
         this.callback = callback;
+
+        processSignedOnly = K9.getOpenPgpSupportSignOnly();
     }
 
 
@@ -276,7 +279,7 @@ public class MessageLoaderHelper {
             retainCryptoHelperFragment.setData(messageCryptoHelper);
         }
         messageCryptoHelper.asyncStartOrResumeProcessingMessage(
-                localMessage, messageCryptoCallback, cachedDecryptionResult);
+                localMessage, messageCryptoCallback, cachedDecryptionResult, processSignedOnly);
     }
 
     private void cancelAndClearCryptoOperation() {

k9mail/src/main/java/com/fsck/k9/ui/crypto/MessageCryptoHelper.java

@@ -84,6 +84,7 @@ public class MessageCryptoHelper {
     private State state;
     private CancelableBackgroundOperation cancelableBackgroundOperation;
     private boolean isCancelled;
+    private boolean processSignedOnly;
 
     private OpenPgpApi openPgpApi;
     private OpenPgpServiceConnection openPgpServiceConnection;
@@ -108,7 +109,7 @@ public class MessageCryptoHelper {
     }
 
     public void asyncStartOrResumeProcessingMessage(Message message, MessageCryptoCallback callback,
-            OpenPgpDecryptionResult cachedDecryptionResult) {
+            OpenPgpDecryptionResult cachedDecryptionResult, boolean processSignedOnly) {
         if (this.currentMessage != null) {
             reattachCallback(message, callback);
             return;
@@ -119,6 +120,7 @@ public class MessageCryptoHelper {
         this.currentMessage = message;
         this.cachedDecryptionResult = cachedDecryptionResult;
         this.callback = callback;
+        this.processSignedOnly = processSignedOnly;
 
         nextStep();
     }
@@ -143,6 +145,13 @@ public class MessageCryptoHelper {
         List<Part> signedParts = MessageCryptoStructureDetector
                 .findMultipartSignedParts(currentMessage, messageAnnotations);
         for (Part part : signedParts) {
+            if (!processSignedOnly) {
+                boolean isEncapsulatedSignature =
+                        messageAnnotations.findKeyForAnnotationWithReplacementPart(part) != null;
+                if (!isEncapsulatedSignature) {
+                    continue;
+                }
+            }
             if (!MessageHelper.isCompletePartAvailable(part)) {
                 MimeBodyPart replacementPart = getMultipartSignedContentPartIfAvailable(part);
                 addErrorAnnotation(part, CryptoError.OPENPGP_SIGNED_BUT_INCOMPLETE, replacementPart);
@@ -161,12 +170,15 @@ public class MessageCryptoHelper {
     private void findPartsForPgpInlinePass() {
         List<Part> inlineParts = MessageCryptoStructureDetector.findPgpInlineParts(currentMessage);
         for (Part part : inlineParts) {
+            if (!processSignedOnly && !MessageCryptoStructureDetector.isPartPgpInlineEncrypted(part)) {
+                continue;
+            }
+
             if (!currentMessage.getFlags().contains(Flag.X_DOWNLOADED_FULL)) {
                 if (MessageCryptoStructureDetector.isPartPgpInlineEncrypted(part)) {
                     addErrorAnnotation(part, CryptoError.OPENPGP_ENCRYPTED_BUT_INCOMPLETE, NO_REPLACEMENT_PART);
                 } else {
-                    MimeBodyPart replacementPart = extractClearsignedTextReplacementPart(part);
+                    addErrorAnnotation(part, CryptoError.OPENPGP_SIGNED_BUT_INCOMPLETE, NO_REPLACEMENT_PART);
-                    addErrorAnnotation(part, CryptoError.OPENPGP_SIGNED_BUT_INCOMPLETE, replacementPart);
                 }
                 continue;
             }

k9mail/src/test/java/com/fsck/k9/ui/crypto/MessageCryptoHelperTest.java

@@ -84,7 +84,7 @@ public class MessageCryptoHelperTest {
         message.setHeader("Content-Type", "text/plain");
 
         MessageCryptoCallback messageCryptoCallback = mock(MessageCryptoCallback.class);
-        messageCryptoHelper.asyncStartOrResumeProcessingMessage(message, messageCryptoCallback, null);
+        messageCryptoHelper.asyncStartOrResumeProcessingMessage(message, messageCryptoCallback, null, false);
 
         ArgumentCaptor<MessageCryptoAnnotations> captor = ArgumentCaptor.forClass(MessageCryptoAnnotations.class);
         verify(messageCryptoCallback).onCryptoOperationsFinished(captor.capture());
@@ -107,7 +107,7 @@ public class MessageCryptoHelperTest {
 
 
         MessageCryptoCallback messageCryptoCallback = mock(MessageCryptoCallback.class);
-        messageCryptoHelper.asyncStartOrResumeProcessingMessage(message, messageCryptoCallback, null);
+        messageCryptoHelper.asyncStartOrResumeProcessingMessage(message, messageCryptoCallback, null, false);
 
 
         ArgumentCaptor<MessageCryptoAnnotations> captor = ArgumentCaptor.forClass(MessageCryptoAnnotations.class);
@@ -132,7 +132,7 @@ public class MessageCryptoHelperTest {
         );
 
         MessageCryptoCallback messageCryptoCallback = mock(MessageCryptoCallback.class);
-        messageCryptoHelper.asyncStartOrResumeProcessingMessage(message, messageCryptoCallback, null);
+        messageCryptoHelper.asyncStartOrResumeProcessingMessage(message, messageCryptoCallback, null, true);
 
         assertPartAnnotationHasState(message, messageCryptoCallback, CryptoError.OPENPGP_SIGNED_BUT_INCOMPLETE, null,
                 null, null, null);
@@ -148,7 +148,7 @@ public class MessageCryptoHelperTest {
         );
 
         MessageCryptoCallback messageCryptoCallback = mock(MessageCryptoCallback.class);
-        messageCryptoHelper.asyncStartOrResumeProcessingMessage(message, messageCryptoCallback, null);
+        messageCryptoHelper.asyncStartOrResumeProcessingMessage(message, messageCryptoCallback, null, false);
 
         assertPartAnnotationHasState(
                 message, messageCryptoCallback, CryptoError.OPENPGP_ENCRYPTED_BUT_INCOMPLETE, null, null, null, null);
@@ -164,7 +164,7 @@ public class MessageCryptoHelperTest {
         );
 
         MessageCryptoCallback messageCryptoCallback = mock(MessageCryptoCallback.class);
-        messageCryptoHelper.asyncStartOrResumeProcessingMessage(message, messageCryptoCallback, null);
+        messageCryptoHelper.asyncStartOrResumeProcessingMessage(message, messageCryptoCallback, null, false);
 
         assertPartAnnotationHasState(message, messageCryptoCallback, CryptoError.ENCRYPTED_BUT_UNSUPPORTED, null, null,
                 null, null);
@@ -180,7 +180,7 @@ public class MessageCryptoHelperTest {
         );
 
         MessageCryptoCallback messageCryptoCallback = mock(MessageCryptoCallback.class);
-        messageCryptoHelper.asyncStartOrResumeProcessingMessage(message, messageCryptoCallback, null);
+        messageCryptoHelper.asyncStartOrResumeProcessingMessage(message, messageCryptoCallback, null, true);
 
         assertPartAnnotationHasState(message, messageCryptoCallback, CryptoError.SIGNED_BUT_UNSUPPORTED, null, null,
                 null, null);
@@ -210,6 +210,36 @@ public class MessageCryptoHelperTest {
         verifyNoMoreInteractions(autocryptOperations);
     }
 
+    @Test
+    public void multipartSigned__withSignOnlyDisabled__shouldReturnNothing() throws Exception {
+        Message message = messageFromBody(
+                multipart("signed", "application/pgp-signature",
+                        bodypart("text/plain", "content"),
+                        bodypart("application/pgp-signature", "content")
+                )
+        );
+
+        MessageCryptoCallback messageCryptoCallback = mock(MessageCryptoCallback.class);
+        messageCryptoHelper.asyncStartOrResumeProcessingMessage(message, messageCryptoCallback, null, false);
+
+        assertReturnsWithNoCryptoAnnotations(messageCryptoCallback);
+    }
+
+    @Test
+    public void multipartSigned__withSignOnlyDisabledAndNullBody__shouldReturnNothing() throws Exception {
+        Message message = messageFromBody(
+                multipart("signed", "application/pgp-signature",
+                        bodypart("text/plain"),
+                        bodypart("application/pgp-signature")
+                )
+        );
+
+        MessageCryptoCallback messageCryptoCallback = mock(MessageCryptoCallback.class);
+        messageCryptoHelper.asyncStartOrResumeProcessingMessage(message, messageCryptoCallback, null, false);
+
+        assertReturnsWithNoCryptoAnnotations(messageCryptoCallback);
+    }
+
     @Test
     public void multipartEncrypted__shouldCallOpenPgpApiAsync() throws Exception {
         Body encryptedBody;
@@ -249,7 +279,7 @@ public class MessageCryptoHelperTest {
 
     private void processEncryptedMessageAndCaptureMocks(Message message, Body encryptedBody, OutputStream outputStream)
             throws Exception {
-        messageCryptoHelper.asyncStartOrResumeProcessingMessage(message, messageCryptoCallback, null);
+        messageCryptoHelper.asyncStartOrResumeProcessingMessage(message, messageCryptoCallback, null, false);
 
         ArgumentCaptor<Intent> intentCaptor = ArgumentCaptor.forClass(Intent.class);
         ArgumentCaptor<OpenPgpDataSource> dataSourceCaptor = ArgumentCaptor.forClass(OpenPgpDataSource.class);
@@ -267,7 +297,7 @@ public class MessageCryptoHelperTest {
 
     private void processSignedMessageAndCaptureMocks(Message message, BodyPart signedBodyPart,
             OutputStream outputStream) throws Exception {
-        messageCryptoHelper.asyncStartOrResumeProcessingMessage(message, messageCryptoCallback, null);
+        messageCryptoHelper.asyncStartOrResumeProcessingMessage(message, messageCryptoCallback, null, true);
 
         ArgumentCaptor<Intent> intentCaptor = ArgumentCaptor.forClass(Intent.class);
         ArgumentCaptor<OpenPgpDataSource> dataSourceCaptor = ArgumentCaptor.forClass(OpenPgpDataSource.class);
@@ -283,6 +313,15 @@ public class MessageCryptoHelperTest {
         verify(signedBodyPart).writeTo(outputStream);
     }
 
+    private void assertReturnsWithNoCryptoAnnotations(MessageCryptoCallback messageCryptoCallback) {
+        ArgumentCaptor<MessageCryptoAnnotations> captor = ArgumentCaptor.forClass(MessageCryptoAnnotations.class);
+        verify(messageCryptoCallback).onCryptoOperationsFinished(captor.capture());
+        verifyNoMoreInteractions(messageCryptoCallback);
+
+        MessageCryptoAnnotations annotations = captor.getValue();
+        assertTrue(annotations.isEmpty());
+    }
+
     private void assertPartAnnotationHasState(Message message, MessageCryptoCallback messageCryptoCallback,
             CryptoError cryptoErrorState, MimeBodyPart replacementPart, OpenPgpDecryptionResult openPgpDecryptionResult,
             OpenPgpSignatureResult openPgpSignatureResult, PendingIntent openPgpPendingIntent) {