Add interface for detection of encrypted messages

This includes some capabilities that are not currently used by K-9 Mail, e.g. the ability to supply additional data to be inserted into the database.
thunderbird · Sep 2, 2018 · a8f4111 · a8f4111
1 parent 18bbd76
commit a8f4111
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Showing 21 changed files with 217 additions and 84 deletions.
diff --git a/app/core/src/main/java/com/fsck/k9/crypto/EncryptionExtractor.kt b/app/core/src/main/java/com/fsck/k9/crypto/EncryptionExtractor.kt
@@ -0,0 +1,17 @@
+package com.fsck.k9.crypto
+
+import android.content.ContentValues
+import com.fsck.k9.mail.Message
+import com.fsck.k9.message.extractors.PreviewResult
+
+interface EncryptionExtractor {
+    fun extractEncryption(message: Message): EncryptionResult?
+}
+
+data class EncryptionResult(
+        val encryptionType: String,
+        val attachmentCount: Int,
+        val previewResult: PreviewResult = PreviewResult.encrypted(),
+        val textForSearchIndex: String? = null,
+        val extraContentValues: ContentValues? = null
+)
diff --git a/app/core/src/main/java/com/fsck/k9/mailstore/LocalFolder.java b/app/core/src/main/java/com/fsck/k9/mailstore/LocalFolder.java
@@ -31,6 +31,8 @@
 import com.fsck.k9.K9;
 import com.fsck.k9.controller.MessageReference;
 import com.fsck.k9.backend.api.MessageRemovalListener;
+import com.fsck.k9.crypto.EncryptionExtractor;
+import com.fsck.k9.crypto.EncryptionResult;
 import com.fsck.k9.helper.FileHelper;
 import com.fsck.k9.helper.Utility;
 import com.fsck.k9.mail.Address;
@@ -77,6 +79,7 @@ public class LocalFolder extends Folder<LocalMessage> {
     private final SearchStatusManager searchStatusManager = DI.get(SearchStatusManager.class);
     private final LocalStore localStore;
     private final AttachmentInfoExtractor attachmentInfoExtractor;
+    private final EncryptionExtractor encryptionExtractor = DI.get(EncryptionExtractor.class);
 
 
     private String serverId = null;
@@ -1379,17 +1382,34 @@ private void saveMessage(SQLiteDatabase db, Message message, boolean copy, Map<S
         }
 
         try {
-            MessagePreviewCreator previewCreator = localStore.getMessagePreviewCreator();
-            PreviewResult previewResult = previewCreator.createPreview(message);
+            String encryptionType;
+            PreviewResult previewResult;
+            int attachmentCount;
+            String fulltext;
+            ContentValues extraContentValues;
+
+            EncryptionResult encryptionResult = encryptionExtractor.extractEncryption(message);
+            if (encryptionResult != null) {
+                encryptionType = encryptionResult.getEncryptionType();
+                previewResult = encryptionResult.getPreviewResult();
+                attachmentCount = encryptionResult.getAttachmentCount();
+                fulltext = encryptionResult.getTextForSearchIndex();
+                extraContentValues = encryptionResult.getExtraContentValues();
+            } else {
+                MessagePreviewCreator previewCreator = localStore.getMessagePreviewCreator();
+                MessageFulltextCreator fulltextCreator = localStore.getMessageFulltextCreator();
+                AttachmentCounter attachmentCounter = localStore.getAttachmentCounter();
+
+                encryptionType = null;
+                previewResult = previewCreator.createPreview(message);
+                attachmentCount = attachmentCounter.getAttachmentCount(message);
+                fulltext = fulltextCreator.createFulltext(message);
+                extraContentValues = null;
+            }
+
             PreviewType previewType = previewResult.getPreviewType();
             DatabasePreviewType databasePreviewType = DatabasePreviewType.fromPreviewType(previewType);
 
-            MessageFulltextCreator fulltextCreator = localStore.getMessageFulltextCreator();
-            String fulltext = fulltextCreator.createFulltext(message);
-
-            AttachmentCounter attachmentCounter = localStore.getAttachmentCounter();
-            int attachmentCount = attachmentCounter.getAttachmentCount(message);
-
             long rootMessagePartId = saveMessageParts(db, message);
 
             ContentValues cv = new ContentValues();
@@ -1415,6 +1435,7 @@ private void saveMessage(SQLiteDatabase db, Message message, boolean copy, Map<S
                     ? System.currentTimeMillis() : message.getInternalDate().getTime());
             cv.put("mime_type", message.getMimeType());
             cv.put("empty", 0);
+            cv.put("encryption_type", encryptionType);
 
             cv.put("preview_type", databasePreviewType.getDatabaseValue());
             if (previewResult.isPreviewTextAvailable()) {
@@ -1428,6 +1449,10 @@ private void saveMessage(SQLiteDatabase db, Message message, boolean copy, Map<S
                 cv.put("message_id", messageId);
             }
 
+            if (extraContentValues != null) {
+                cv.putAll(extraContentValues);
+            }
+
             if (oldMessageId == -1) {
                 msgId = db.insert("messages", "uid", cv);
 

diff --git a/app/core/src/main/java/com/fsck/k9/message/extractors/AttachmentCounter.java b/app/core/src/main/java/com/fsck/k9/message/extractors/AttachmentCounter.java
@@ -11,24 +11,12 @@
 
 
 public class AttachmentCounter {
-    private final EncryptionDetector encryptionDetector;
-
-
-    AttachmentCounter(EncryptionDetector encryptionDetector) {
-        this.encryptionDetector = encryptionDetector;
-    }
 
     public static AttachmentCounter newInstance() {
-        TextPartFinder textPartFinder = new TextPartFinder();
-        EncryptionDetector encryptionDetector = new EncryptionDetector(textPartFinder);
-        return new AttachmentCounter(encryptionDetector);
+        return new AttachmentCounter();
     }
 
     public int getAttachmentCount(Message message) throws MessagingException {
-        if (encryptionDetector.isEncrypted(message)) {
-            return 0;
-        }
-
         List<Part> attachmentParts = new ArrayList<>();
         MessageExtractor.findViewablesAndAttachments(message, null, attachmentParts);
 

diff --git a/app/core/src/main/java/com/fsck/k9/message/extractors/MessageFulltextCreator.java b/app/core/src/main/java/com/fsck/k9/message/extractors/MessageFulltextCreator.java
@@ -15,29 +15,18 @@ public class MessageFulltextCreator {
 
 
     private final TextPartFinder textPartFinder;
-    private final EncryptionDetector encryptionDetector;
 
 
-    MessageFulltextCreator(TextPartFinder textPartFinder, EncryptionDetector encryptionDetector) {
+    MessageFulltextCreator(TextPartFinder textPartFinder) {
         this.textPartFinder = textPartFinder;
-        this.encryptionDetector = encryptionDetector;
     }
 
     public static MessageFulltextCreator newInstance() {
         TextPartFinder textPartFinder = new TextPartFinder();
-        EncryptionDetector encryptionDetector = new EncryptionDetector(textPartFinder);
-        return new MessageFulltextCreator(textPartFinder, encryptionDetector);
+        return new MessageFulltextCreator(textPartFinder);
     }
 
     public String createFulltext(@NonNull Message message) {
-        if (encryptionDetector.isEncrypted(message)) {
-            return null;
-        }
-
-        return extractText(message);
-    }
-
-    private String extractText(Message message) {
         Part textPart = textPartFinder.findFirstTextPart(message);
         if (textPart == null || hasEmptyBody(textPart)) {
             return null;

diff --git a/app/core/src/main/java/com/fsck/k9/message/extractors/MessagePreviewCreator.java b/app/core/src/main/java/com/fsck/k9/message/extractors/MessagePreviewCreator.java
@@ -10,32 +10,20 @@
 public class MessagePreviewCreator {
     private final TextPartFinder textPartFinder;
     private final PreviewTextExtractor previewTextExtractor;
-    private final EncryptionDetector encryptionDetector;
 
 
-    MessagePreviewCreator(TextPartFinder textPartFinder, PreviewTextExtractor previewTextExtractor,
-            EncryptionDetector encryptionDetector) {
+    MessagePreviewCreator(TextPartFinder textPartFinder, PreviewTextExtractor previewTextExtractor) {
         this.textPartFinder = textPartFinder;
         this.previewTextExtractor = previewTextExtractor;
-        this.encryptionDetector = encryptionDetector;
     }
 
     public static MessagePreviewCreator newInstance() {
         TextPartFinder textPartFinder = new TextPartFinder();
         PreviewTextExtractor previewTextExtractor = new PreviewTextExtractor();
-        EncryptionDetector encryptionDetector = new EncryptionDetector(textPartFinder);
-        return new MessagePreviewCreator(textPartFinder, previewTextExtractor, encryptionDetector);
+        return new MessagePreviewCreator(textPartFinder, previewTextExtractor);
     }
 
     public PreviewResult createPreview(@NonNull Message message) {
-        if (encryptionDetector.isEncrypted(message)) {
-            return PreviewResult.encrypted();
-        }
-
-        return extractText(message);
-    }
-
-    private PreviewResult extractText(Message message) {
         Part textPart = textPartFinder.findFirstTextPart(message);
         if (textPart == null || hasEmptyBody(textPart)) {
             return PreviewResult.none();

diff --git a/app/core/src/main/java/com/fsck/k9/message/extractors/TextPartFinder.java b/app/core/src/main/java/com/fsck/k9/message/extractors/TextPartFinder.java
@@ -12,7 +12,7 @@
 import static com.fsck.k9.mail.internet.MimeUtility.isSameMimeType;
 
 
-class TextPartFinder {
+public class TextPartFinder {
     @Nullable
     public Part findFirstTextPart(@NonNull Part part) {
         String mimeType = part.getMimeType();

diff --git a/app/core/src/test/java/com/fsck/k9/TestApp.kt b/app/core/src/test/java/com/fsck/k9/TestApp.kt
@@ -1,6 +1,7 @@
 package com.fsck.k9
 
 import android.app.Application
+import com.fsck.k9.crypto.EncryptionExtractor
 import com.fsck.k9.storage.storageModule
 import com.nhaarman.mockito_kotlin.mock
 import org.koin.dsl.module.applicationContext
@@ -20,4 +21,5 @@ class TestApp : Application() {
 val testModule = applicationContext {
     bean { AppConfig(emptyList()) }
     bean { mock<CoreResourceProvider>() }
+    bean { mock<EncryptionExtractor>() }
 }
diff --git a/app/core/src/test/java/com/fsck/k9/message/extractors/MessagePreviewCreatorTest.java b/app/core/src/test/java/com/fsck/k9/message/extractors/MessagePreviewCreatorTest.java
@@ -21,35 +21,19 @@
 public class MessagePreviewCreatorTest {
     private TextPartFinder textPartFinder;
     private PreviewTextExtractor previewTextExtractor;
-    private EncryptionDetector encryptionDetector;
     private MessagePreviewCreator previewCreator;
 
     @Before
     public void setUp() throws Exception {
         textPartFinder = mock(TextPartFinder.class);
         previewTextExtractor = mock(PreviewTextExtractor.class);
-        encryptionDetector = mock(EncryptionDetector.class);
 
-        previewCreator = new MessagePreviewCreator(textPartFinder, previewTextExtractor, encryptionDetector);
+        previewCreator = new MessagePreviewCreator(textPartFinder, previewTextExtractor);
     }
 
     @Test
-    public void createPreview_withEncryptedMessage() throws Exception {
+    public void createPreview_withoutTextPart() {
         Message message = createDummyMessage();
-        when(encryptionDetector.isEncrypted(message)).thenReturn(true);
-
-        PreviewResult result = previewCreator.createPreview(message);
-
-        assertFalse(result.isPreviewTextAvailable());
-        assertEquals(PreviewType.ENCRYPTED, result.getPreviewType());
-        verifyNoMoreInteractions(textPartFinder);
-        verifyNoMoreInteractions(previewTextExtractor);
-    }
-
-    @Test
-    public void createPreview_withoutTextPart() throws Exception {
-        Message message = createDummyMessage();
-        when(encryptionDetector.isEncrypted(message)).thenReturn(false);
         when(textPartFinder.findFirstTextPart(message)).thenReturn(null);
 
         PreviewResult result = previewCreator.createPreview(message);
@@ -63,7 +47,6 @@ public void createPreview_withoutTextPart() throws Exception {
     public void createPreview_withEmptyTextPart() throws Exception {
         Message message = createDummyMessage();
         Part textPart = createEmptyPart("text/plain");
-        when(encryptionDetector.isEncrypted(message)).thenReturn(false);
         when(textPartFinder.findFirstTextPart(message)).thenReturn(textPart);
 
         PreviewResult result = previewCreator.createPreview(message);
@@ -77,7 +60,6 @@ public void createPreview_withEmptyTextPart() throws Exception {
     public void createPreview_withTextPart() throws Exception {
         Message message = createDummyMessage();
         Part textPart = createTextPart("text/plain");
-        when(encryptionDetector.isEncrypted(message)).thenReturn(false);
         when(textPartFinder.findFirstTextPart(message)).thenReturn(textPart);
         when(previewTextExtractor.extractPreview(textPart)).thenReturn("expected");
 
@@ -92,7 +74,6 @@ public void createPreview_withTextPart() throws Exception {
     public void createPreview_withPreviewTextExtractorThrowing() throws Exception {
         Message message = createDummyMessage();
         Part textPart = createTextPart("text/plain");
-        when(encryptionDetector.isEncrypted(message)).thenReturn(false);
         when(textPartFinder.findFirstTextPart(message)).thenReturn(textPart);
         when(previewTextExtractor.extractPreview(textPart)).thenThrow(new PreviewExtractionException(""));
 

diff --git a/app/crypto-openpgp/build.gradle b/app/crypto-openpgp/build.gradle
@@ -0,0 +1,33 @@
+apply plugin: 'com.android.library'
+apply plugin: 'org.jetbrains.kotlin.android'
+
+apply from: "${rootProject.projectDir}/gradle/plugins/checkstyle-android.gradle"
+apply from: "${rootProject.projectDir}/gradle/plugins/findbugs-android.gradle"
+
+dependencies {
+    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:${versions.kotlin}"
+
+    implementation project(":app:core")
+
+    testImplementation "junit:junit:${versions.junit}"
+    testImplementation "org.mockito:mockito-core:${versions.mockito}"
+}
+
+android {
+    compileSdkVersion buildConfig.compileSdk
+    buildToolsVersion buildConfig.buildTools
+
+    defaultConfig {
+        minSdkVersion buildConfig.minSdk
+    }
+
+    lintOptions {
+        abortOnError false
+        lintConfig file("$rootProject.projectDir/config/lint/lint.xml")
+    }
+
+    compileOptions {
+        sourceCompatibility JavaVersion.VERSION_1_7
+        targetCompatibility JavaVersion.VERSION_1_7
+    }
+}
diff --git a/app/crypto-openpgp/src/main/AndroidManifest.xml b/app/crypto-openpgp/src/main/AndroidManifest.xml
@@ -0,0 +1,2 @@
+<?xml version="1.0" encoding="utf-8"?>
+<manifest package="com.fsck.k9.crypto.openpgp" />
diff --git a/...essage/extractors/EncryptionDetector.java → ...k9/crypto/openpgp/EncryptionDetector.java b/...essage/extractors/EncryptionDetector.java → ...k9/crypto/openpgp/EncryptionDetector.java
@@ -1,4 +1,4 @@
-package com.fsck.k9.message.extractors;
+package com.fsck.k9.crypto.openpgp;
 
 
 import android.support.annotation.NonNull;
@@ -9,10 +9,12 @@
 import com.fsck.k9.mail.Message;
 import com.fsck.k9.mail.Multipart;
 import com.fsck.k9.mail.Part;
+import com.fsck.k9.message.extractors.TextPartFinder;
 
 import static com.fsck.k9.mail.internet.MimeUtility.isSameMimeType;
 
 
+//FIXME: Make this only detect OpenPGP messages. Move support for S/MIME messages to separate module.
 class EncryptionDetector {
     private final TextPartFinder textPartFinder;
 

diff --git a/app/crypto-openpgp/src/main/java/com/fsck/k9/crypto/openpgp/OpenPgpEncryptionExtractor.kt b/app/crypto-openpgp/src/main/java/com/fsck/k9/crypto/openpgp/OpenPgpEncryptionExtractor.kt
@@ -0,0 +1,31 @@
+package com.fsck.k9.crypto.openpgp
+
+import com.fsck.k9.crypto.EncryptionExtractor
+import com.fsck.k9.crypto.EncryptionResult
+import com.fsck.k9.mail.Message
+import com.fsck.k9.message.extractors.TextPartFinder
+
+class OpenPgpEncryptionExtractor internal constructor(
+        private val encryptionDetector: EncryptionDetector
+) : EncryptionExtractor {
+
+    override fun extractEncryption(message: Message): EncryptionResult? {
+        return if (encryptionDetector.isEncrypted(message)) {
+            EncryptionResult(ENCRYPTION_TYPE, 0)
+        } else {
+            null
+        }
+    }
+
+
+    companion object {
+        const val ENCRYPTION_TYPE = "openpgp"
+
+        @JvmStatic
+        fun newInstance(): OpenPgpEncryptionExtractor {
+            val textPartFinder = TextPartFinder()
+            val encryptionDetector = EncryptionDetector(textPartFinder)
+            return OpenPgpEncryptionExtractor(encryptionDetector)
+        }
+    }
+}