introduced CryptoOperationHelper in ImportKeysActivity

9 files changed, 778 insertions, 511 deletions

diff --git a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/operations/ImportExportOperation.java b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/operations/ImportExportOperation.java
index cdda42dae..c7f0ef423 100644
--- a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/operations/ImportExportOperation.java
+++ b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/operations/ImportExportOperation.java
@@ -22,6 +22,7 @@ import android.content.Context;
 import android.database.Cursor;
 import android.net.Uri;
 
+import android.os.Parcelable;
 import org.spongycastle.bcpg.ArmoredOutputStream;
 import org.sufficientlysecure.keychain.Constants;
 import org.sufficientlysecure.keychain.R;
@@ -33,6 +34,7 @@ import org.sufficientlysecure.keychain.keyimport.ParcelableKeyRing;
 import org.sufficientlysecure.keychain.operations.results.ConsolidateResult;
 import org.sufficientlysecure.keychain.operations.results.ExportResult;
 import org.sufficientlysecure.keychain.operations.results.ImportKeyResult;
+import org.sufficientlysecure.keychain.operations.results.OperationResult;
 import org.sufficientlysecure.keychain.operations.results.OperationResult.LogType;
 import org.sufficientlysecure.keychain.operations.results.OperationResult.OperationLog;
 import org.sufficientlysecure.keychain.operations.results.SaveKeyringResult;
@@ -45,6 +47,9 @@ import org.sufficientlysecure.keychain.provider.KeychainContract.KeyRings;
 import org.sufficientlysecure.keychain.provider.KeychainDatabase.Tables;
 import org.sufficientlysecure.keychain.provider.ProviderHelper;
 import org.sufficientlysecure.keychain.service.ContactSyncAdapterService;
+import org.sufficientlysecure.keychain.service.ImportKeyringParcel;
+import org.sufficientlysecure.keychain.service.input.CryptoInputParcel;
+import org.sufficientlysecure.keychain.service.input.RequiredInputParcel;
 import org.sufficientlysecure.keychain.ui.util.KeyFormattingUtils;
 import org.sufficientlysecure.keychain.util.FileHelper;
 import org.sufficientlysecure.keychain.util.Log;
@@ -59,9 +64,18 @@ import java.io.FileNotFoundException;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.OutputStream;
+import java.net.Proxy;
 import java.util.ArrayList;
+import java.util.HashSet;
 import java.util.Iterator;
 import java.util.List;
+import java.util.concurrent.Callable;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.ExecutorCompletionService;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.SynchronousQueue;
+import java.util.concurrent.ThreadPoolExecutor;
+import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicBoolean;
 
 /** An operation class which implements high level import and export
@@ -87,7 +101,7 @@ import java.util.concurrent.atomic.AtomicBoolean;
  * TODO rework uploadKeyRingToServer
  *
  */
-public class ImportExportOperation extends BaseOperation {
+public class ImportExportOperation extends BaseOperation<ImportKeyringParcel> {
 
     public ImportExportOperation(Context context, ProviderHelper providerHelper, Progressable progressable) {
         super(context, providerHelper, progressable);
@@ -127,23 +141,41 @@ public class ImportExportOperation extends BaseOperation {
         }
     }
 
-    public ImportKeyResult importKeyRings(List<ParcelableKeyRing> entries, String keyServerUri) {
+    // Overloaded functions for using progressable supplied in constructor during import
+    public ImportKeyResult serialKeyRingImport(Iterator<ParcelableKeyRing> entries, int num,
+                                               String keyServerUri) {
+        return serialKeyRingImport(entries, num, keyServerUri, mProgressable);
+    }
+
+    public ImportKeyResult serialKeyRingImport(List<ParcelableKeyRing> entries,
+                                               String keyServerUri) {
 
         Iterator<ParcelableKeyRing> it = entries.iterator();
         int numEntries = entries.size();
 
-        return importKeyRings(it, numEntries, keyServerUri);
+        return serialKeyRingImport(it, numEntries, keyServerUri, mProgressable);
 
     }
 
-    public ImportKeyResult importKeyRings(ParcelableFileCache<ParcelableKeyRing> cache, String keyServerUri) {
+    public ImportKeyResult serialKeyRingImport(List<ParcelableKeyRing> entries, String keyServerUri,
+                                               Progressable progressable) {
+
+        Iterator<ParcelableKeyRing> it = entries.iterator();
+        int numEntries = entries.size();
+
+        return serialKeyRingImport(it, numEntries, keyServerUri, progressable);
+
+    }
+
+    public ImportKeyResult serialKeyRingImport(ParcelableFileCache<ParcelableKeyRing> cache,
+                                               String keyServerUri) {
 
         // get entries from cached file
         try {
             IteratorWithSize<ParcelableKeyRing> it = cache.readCache();
             int numEntries = it.getSize();
 
-            return importKeyRings(it, numEntries, keyServerUri);
+            return serialKeyRingImport(it, numEntries, keyServerUri, mProgressable);
         } catch (IOException e) {
 
             // Special treatment here, we need a lot
@@ -157,15 +189,18 @@ public class ImportExportOperation extends BaseOperation {
     }
 
     /**
-     * Since the introduction of multithreaded import, we expect calling functions to handle the key sync i,e
-     * ContactSyncAdapterService.requestSync()
+     * Since the introduction of multithreaded import, we expect calling functions to handle the
+     * key sync i,eContactSyncAdapterService.requestSync()
      *
-     * @param entries keys to import
-     * @param num number of keys to import
+     * @param entries      keys to import
+     * @param num          number of keys to import
      * @param keyServerUri contains uri of keyserver to import from, if it is an import from cloud
+     * @param progressable Allows multi-threaded import to supply a progressable that ignores the
+     *                     progress of a single key being imported
      * @return
      */
-    public ImportKeyResult importKeyRings(Iterator<ParcelableKeyRing> entries, int num, String keyServerUri) {
+    public ImportKeyResult serialKeyRingImport(Iterator<ParcelableKeyRing> entries, int num,
+                                               String keyServerUri, Progressable progressable) {
         updateProgress(R.string.progress_importing, 0, 100);
 
         OperationLog log = new OperationLog();
@@ -224,7 +259,8 @@ public class ImportExportOperation extends BaseOperation {
                             byte[] data;
                             // Download by fingerprint, or keyId - whichever is available
                             if (entry.mExpectedFingerprint != null) {
-                                log.add(LogType.MSG_IMPORT_FETCH_KEYSERVER, 2, "0x" + entry.mExpectedFingerprint.substring(24));
+                                log.add(LogType.MSG_IMPORT_FETCH_KEYSERVER, 2, "0x" +
+                                        entry.mExpectedFingerprint.substring(24));
                                 data = keyServer.get("0x" + entry.mExpectedFingerprint).getBytes();
                             } else {
                                 log.add(LogType.MSG_IMPORT_FETCH_KEYSERVER, 2, entry.mKeyIdHex);
@@ -302,10 +338,12 @@ public class ImportExportOperation extends BaseOperation {
                 mProviderHelper.clearLog();
                 if (key.isSecret()) {
                     result = mProviderHelper.saveSecretKeyRing(key,
-                            new ProgressScaler(mProgressable, (int)(position*progSteps), (int)((position+1)*progSteps), 100));
+                            new ProgressScaler(progressable, (int)(position*progSteps),
+                                    (int)((position+1)*progSteps), 100));
                 } else {
                     result = mProviderHelper.savePublicKeyRing(key,
-                            new ProgressScaler(mProgressable, (int)(position*progSteps), (int)((position+1)*progSteps), 100));
+                            new ProgressScaler(progressable, (int)(position*progSteps),
+                                    (int)((position+1)*progSteps), 100));
                 }
                 if (!result.success()) {
                     badKeys += 1;
@@ -333,7 +371,7 @@ public class ImportExportOperation extends BaseOperation {
         // Special: consolidate on secret key import (cannot be cancelled!)
         if (secret > 0) {
             setPreventCancel();
-            ConsolidateResult result = mProviderHelper.consolidateDatabaseStep1(mProgressable);
+            ConsolidateResult result = mProviderHelper.consolidateDatabaseStep1(progressable);
             log.add(result, 1);
         }
 
@@ -590,4 +628,210 @@ public class ImportExportOperation extends BaseOperation {
 
     }
 
-}
+    @Override
+    public ImportKeyResult execute(ImportKeyringParcel input, CryptoInputParcel cryptoInput) {
+
+        return importKeys(input.mKeyList, input.mKeyserver);
+    }
+
+    public ImportKeyResult importKeys(ArrayList<ParcelableKeyRing> keyList, String keyServer) {
+
+        ImportKeyResult result;
+
+        if (keyList == null) {// import from file, do serially
+            ParcelableFileCache<ParcelableKeyRing> cache = new ParcelableFileCache<>(mContext,
+                    "key_import.pcl");
+
+            result =  serialKeyRingImport(cache, keyServer);
+        } else {
+            // if there is more than one key with the same fingerprint, we do a serial import to prevent
+            // https://github.com/open-keychain/open-keychain/issues/1221
+            HashSet<String> keyFingerprintSet = new HashSet<>();
+            for (int i = 0; i < keyList.size(); i++) {
+                keyFingerprintSet.add(keyList.get(i).mExpectedFingerprint);
+            }
+            if (keyFingerprintSet.size() == keyList.size()) {
+                // all keys have unique fingerprints
+                result =  multiThreadedKeyImport(keyList.iterator(), keyList.size(), keyServer);
+            } else {
+                result = serialKeyRingImport(keyList, keyServer);
+            }
+        }
+
+        ContactSyncAdapterService.requestSync();
+        return result;
+    }
+
+    private ImportKeyResult multiThreadedKeyImport(Iterator<ParcelableKeyRing> keyListIterator,
+                                                   int totKeys, final String keyServer) {
+        Log.d(Constants.TAG, "Multi-threaded key import starting");
+        if (keyListIterator != null) {
+            KeyImportAccumulator accumulator = new KeyImportAccumulator(totKeys, mProgressable);
+
+            final Progressable ignoreProgressable = new Progressable() {
+                @Override
+                public void setProgress(String message, int current, int total) {
+
+                }
+
+                @Override
+                public void setProgress(int resourceId, int current, int total) {
+
+                }
+
+                @Override
+                public void setProgress(int current, int total) {
+
+                }
+
+                @Override
+                public void setPreventCancel() {
+
+                }
+            };
+
+
+            final int maxThreads = 200;
+            ExecutorService importExecutor = new ThreadPoolExecutor(0, maxThreads,
+                    30L, TimeUnit.SECONDS,
+                    new SynchronousQueue<Runnable>());
+
+            ExecutorCompletionService<ImportKeyResult> importCompletionService =
+                    new ExecutorCompletionService(importExecutor);
+
+            while (keyListIterator.hasNext()) { // submit all key rings to be imported
+
+                final ParcelableKeyRing pkRing = keyListIterator.next();
+
+                Callable<ImportKeyResult> importOperationCallable = new Callable<ImportKeyResult>() {
+
+                    @Override
+                    public ImportKeyResult call() {
+
+                        ArrayList<ParcelableKeyRing> list = new ArrayList<>();
+                        list.add(pkRing);
+
+                        return serialKeyRingImport(list, keyServer, ignoreProgressable);
+                    }
+                };
+
+                importCompletionService.submit(importOperationCallable);
+            }
+
+            while (!accumulator.isImportFinished()) { // accumulate the results of each import
+                try {
+                    accumulator.accumulateKeyImport(importCompletionService.take().get());
+                } catch (InterruptedException | ExecutionException e) {
+                    Log.e(Constants.TAG, "A key could not be imported during multi-threaded import", e);
+                    // do nothing?
+                    if (e instanceof ExecutionException) {
+                        // Since serialKeyRingImport does not throw any exceptions, this is what would have happened if
+                        // we were importing the key on this thread
+                        throw new RuntimeException();
+                    }
+                }
+            }
+            return accumulator.getConsolidatedResult();
+        }
+        return null; // TODO: Decide if we should just crash instead of returning null
+    }
+
+    /**
+     * Used to accumulate the results of individual key imports
+     */
+    private class KeyImportAccumulator {
+        private OperationResult.OperationLog mImportLog = new OperationResult.OperationLog();
+        Progressable mProgressable;
+        private int mTotalKeys;
+        private int mImportedKeys = 0;
+        ArrayList<Long> mImportedMasterKeyIds = new ArrayList<Long>();
+        private int mBadKeys = 0;
+        private int mNewKeys = 0;
+        private int mUpdatedKeys = 0;
+        private int mSecret = 0;
+        private int mResultType = 0;
+
+        /**
+         * Accumulates keyring imports and updates the progressable whenever a new key is imported.
+         * Also sets the progress to 0 on instantiation.
+         *
+         * @param totalKeys            total number of keys to be imported
+         * @param externalProgressable the external progressable to be updated every time a key is imported
+         */
+        public KeyImportAccumulator(int totalKeys, Progressable externalProgressable) {
+            mTotalKeys = totalKeys;
+            mProgressable = externalProgressable;
+            mProgressable.setProgress(0, totalKeys);
+        }
+
+        public int getTotalKeys() {
+            return mTotalKeys;
+        }
+
+        public int getImportedKeys() {
+            return mImportedKeys;
+        }
+
+        public synchronized void accumulateKeyImport(ImportKeyResult result) {
+            mImportedKeys++;
+
+            mProgressable.setProgress(mImportedKeys, mTotalKeys);
+
+            mImportLog.addAll(result.getLog().toList());//accumulates log
+            mBadKeys += result.mBadKeys;
+            mNewKeys += result.mNewKeys;
+            mUpdatedKeys += result.mUpdatedKeys;
+            mSecret += result.mSecret;
+
+            long[] masterKeyIds = result.getImportedMasterKeyIds();
+            for (long masterKeyId : masterKeyIds) {
+                mImportedMasterKeyIds.add(masterKeyId);
+            }
+
+            // if any key import has been cancelled, set result type to cancelled
+            // resultType is added to in getConsolidatedKayImport to account for remaining factors
+            mResultType |= result.getResult() & ImportKeyResult.RESULT_CANCELLED;
+        }
+
+        /**
+         * returns accumulated result of all imports so far
+         */
+        public ImportKeyResult getConsolidatedResult() {
+
+            // adding required information to mResultType
+            // special case,no keys requested for import
+            if (mBadKeys == 0 && mNewKeys == 0 && mUpdatedKeys == 0) {
+                mResultType = ImportKeyResult.RESULT_FAIL_NOTHING;
+            } else {
+                if (mNewKeys > 0) {
+                    mResultType |= ImportKeyResult.RESULT_OK_NEWKEYS;
+                }
+                if (mUpdatedKeys > 0) {
+                    mResultType |= ImportKeyResult.RESULT_OK_UPDATED;
+                }
+                if (mBadKeys > 0) {
+                    mResultType |= ImportKeyResult.RESULT_WITH_ERRORS;
+                    if (mNewKeys == 0 && mUpdatedKeys == 0) {
+                        mResultType |= ImportKeyResult.RESULT_ERROR;
+                    }
+                }
+                if (mImportLog.containsWarnings()) {
+                    mResultType |= ImportKeyResult.RESULT_WARNINGS;
+                }
+            }
+
+            long masterKeyIds[] = new long[mImportedMasterKeyIds.size()];
+            for (int i = 0; i < masterKeyIds.length; i++) {
+                masterKeyIds[i] = mImportedMasterKeyIds.get(i);
+            }
+
+            return new ImportKeyResult(mResultType, mImportLog, mNewKeys, mUpdatedKeys, mBadKeys,
+                    mSecret, masterKeyIds);
+        }
+
+        public boolean isImportFinished() {
+            return mTotalKeys == mImportedKeys;
+        }
+    }
+
+}
\ No newline at end of file
diff --git a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/provider/ProviderHelper.java b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/provider/ProviderHelper.java
index bf7014853..5fbc7f6c7 100644
--- a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/provider/ProviderHelper.java
+++ b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/provider/ProviderHelper.java
@@ -1250,7 +1250,7 @@ public class ProviderHelper {
 
                     ImportKeyResult result = new ImportExportOperation(mContext, this,
                             new ProgressFixedScaler(progress, 10, 25, 100, R.string.progress_con_reimport))
-                            .importKeyRings(itSecrets, numSecrets, null);
+                            .serialKeyRingImport(itSecrets, numSecrets, null);
                     log.add(result, indent);
                 } else {
                     log.add(LogType.MSG_CON_REIMPORT_SECRET_SKIP, indent);
@@ -1278,7 +1278,7 @@ public class ProviderHelper {
 
                     ImportKeyResult result = new ImportExportOperation(mContext, this,
                             new ProgressFixedScaler(progress, 25, 99, 100, R.string.progress_con_reimport))
-                            .importKeyRings(itPublics, numPublics, null);
+                            .serialKeyRingImport(itPublics, numPublics, null);
                     log.add(result, indent);
                 } else {
                     log.add(LogType.MSG_CON_REIMPORT_PUBLIC_SKIP, indent);
diff --git a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/service/ImportKeyringParcel.java b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/service/ImportKeyringParcel.java
new file mode 100644
index 000000000..a41dd71cb
--- /dev/null
+++ b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/service/ImportKeyringParcel.java
@@ -0,0 +1,74 @@
+/*
+ * Copyright (C) 2015 Dominik Schürmann <dominik@dominikschuermann.de>
+ * Copyright (C) 2015 Adithya Abraham Philip <adithyaphilip@gmail.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package org.sufficientlysecure.keychain.service;
+
+import android.os.Parcel;
+import android.os.Parcelable;
+import org.sufficientlysecure.keychain.keyimport.ParcelableKeyRing;
+
+import java.util.ArrayList;
+
+public class ImportKeyringParcel implements Parcelable {
+    // if null, keys are expected to be read from a cache file in ImportExportOperations
+    public ArrayList<ParcelableKeyRing> mKeyList;
+    public String mKeyserver; // must be set if keys are to be imported from a keyserver
+
+    public ImportKeyringParcel (ArrayList<ParcelableKeyRing> keyList, String keyserver) {
+        mKeyList = keyList;
+        mKeyserver = keyserver;
+    }
+
+    protected ImportKeyringParcel(Parcel in) {
+        if (in.readByte() == 0x01) {
+            mKeyList = new ArrayList<>();
+            in.readList(mKeyList, ParcelableKeyRing.class.getClassLoader());
+        } else {
+            mKeyList = null;
+        }
+        mKeyserver = in.readString();
+    }
+
+    @Override
+    public int describeContents() {
+        return 0;
+    }
+
+    @Override
+    public void writeToParcel(Parcel dest, int flags) {
+        if (mKeyList == null) {
+            dest.writeByte((byte) (0x00));
+        } else {
+            dest.writeByte((byte) (0x01));
+            dest.writeList(mKeyList);
+        }
+        dest.writeString(mKeyserver);
+    }
+
+    public static final Parcelable.Creator<ImportKeyringParcel> CREATOR = new Parcelable.Creator<ImportKeyringParcel>() {
+        @Override
+        public ImportKeyringParcel createFromParcel(Parcel in) {
+            return new ImportKeyringParcel(in);
+        }
+
+        @Override
+        public ImportKeyringParcel[] newArray(int size) {
+            return new ImportKeyringParcel[size];
+        }
+    };
+}
\ No newline at end of file
diff --git a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/service/KeychainNewService.java b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/service/KeychainNewService.java
index 9e33a1421..822c2b12e 100644
--- a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/service/KeychainNewService.java
+++ b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/service/KeychainNewService.java
@@ -31,10 +31,7 @@ import android.os.Parcelable;
 import android.os.RemoteException;
 
 import org.sufficientlysecure.keychain.Constants;
-import org.sufficientlysecure.keychain.operations.BaseOperation;
-import org.sufficientlysecure.keychain.operations.CertifyOperation;
-import org.sufficientlysecure.keychain.operations.EditKeyOperation;
-import org.sufficientlysecure.keychain.operations.SignEncryptOperation;
+import org.sufficientlysecure.keychain.operations.*;
 import org.sufficientlysecure.keychain.operations.results.OperationResult;
 import org.sufficientlysecure.keychain.pgp.PgpDecryptVerify;
 import org.sufficientlysecure.keychain.pgp.PgpDecryptVerifyInputParcel;
@@ -96,13 +93,19 @@ public class KeychainNewService extends Service implements Progressable {
                 // just for brevity
                 KeychainNewService outerThis = KeychainNewService.this;
                 if (inputParcel instanceof SignEncryptParcel) {
-                    op = new SignEncryptOperation(outerThis, new ProviderHelper(outerThis), outerThis, mActionCanceled);
+                    op = new SignEncryptOperation(outerThis, new ProviderHelper(outerThis),
+                            outerThis, mActionCanceled);
                 } else if (inputParcel instanceof PgpDecryptVerifyInputParcel) {
                     op = new PgpDecryptVerify(outerThis, new ProviderHelper(outerThis), outerThis);
                 } else if (inputParcel instanceof SaveKeyringParcel) {
-                    op = new EditKeyOperation(outerThis, new ProviderHelper(outerThis), outerThis, mActionCanceled);
+                    op = new EditKeyOperation(outerThis, new ProviderHelper(outerThis), outerThis,
+                            mActionCanceled);
                 } else if (inputParcel instanceof CertifyAction) {
-                    op = new CertifyOperation(outerThis, new ProviderHelper(outerThis), outerThis, mActionCanceled);
+                    op = new CertifyOperation(outerThis, new ProviderHelper(outerThis), outerThis,
+                            mActionCanceled);
+                } else if (inputParcel instanceof ImportKeyringParcel){
+                    op = new ImportExportOperation(outerThis, new ProviderHelper(outerThis),
+                            outerThis, mActionCanceled);
                 } else {
                     return;
                 }
diff --git a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/service/KeychainService.java b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/service/KeychainService.java
index ba877c2a2..bcd5d837f 100644
--- a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/service/KeychainService.java
+++ b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/service/KeychainService.java
@@ -37,13 +37,10 @@ import org.sufficientlysecure.keychain.R;
 import org.sufficientlysecure.keychain.keyimport.HkpKeyserver;
 import org.sufficientlysecure.keychain.keyimport.Keyserver;
 import org.sufficientlysecure.keychain.keyimport.ParcelableKeyRing;
-import org.sufficientlysecure.keychain.operations.CertifyOperation;
 import org.sufficientlysecure.keychain.operations.DeleteOperation;
 import org.sufficientlysecure.keychain.operations.EditKeyOperation;
 import org.sufficientlysecure.keychain.operations.ImportExportOperation;
 import org.sufficientlysecure.keychain.operations.PromoteKeyOperation;
-import org.sufficientlysecure.keychain.operations.SignEncryptOperation;
-import org.sufficientlysecure.keychain.operations.results.CertifyResult;
 import org.sufficientlysecure.keychain.operations.results.ConsolidateResult;
 import org.sufficientlysecure.keychain.operations.results.DecryptVerifyResult;
 import org.sufficientlysecure.keychain.operations.results.DeleteResult;
@@ -52,30 +49,21 @@ import org.sufficientlysecure.keychain.operations.results.ImportKeyResult;
 import org.sufficientlysecure.keychain.operations.results.OperationResult;
 import org.sufficientlysecure.keychain.operations.results.OperationResult.OperationLog;
 import org.sufficientlysecure.keychain.operations.results.PromoteKeyResult;
-import org.sufficientlysecure.keychain.operations.results.SignEncryptResult;
 import org.sufficientlysecure.keychain.pgp.CanonicalizedPublicKeyRing;
 import org.sufficientlysecure.keychain.pgp.PgpDecryptVerify;
 import org.sufficientlysecure.keychain.pgp.PgpDecryptVerifyInputParcel;
 import org.sufficientlysecure.keychain.pgp.Progressable;
-import org.sufficientlysecure.keychain.pgp.SignEncryptParcel;
 import org.sufficientlysecure.keychain.pgp.exception.PgpGeneralException;
 import org.sufficientlysecure.keychain.pgp.exception.PgpGeneralMsgIdException;
 import org.sufficientlysecure.keychain.provider.ProviderHelper;
 import org.sufficientlysecure.keychain.service.input.CryptoInputParcel;
 import org.sufficientlysecure.keychain.service.ServiceProgressHandler.MessageStatus;
 import org.sufficientlysecure.keychain.util.Log;
-import org.sufficientlysecure.keychain.util.ParcelableFileCache;
 
 import java.io.ByteArrayInputStream;
 import java.io.InputStream;
 import java.util.ArrayList;
-import java.util.HashSet;
-import java.util.Iterator;
 import java.util.List;
-import java.util.concurrent.ExecutorService;
-import java.util.concurrent.SynchronousQueue;
-import java.util.concurrent.ThreadPoolExecutor;
-import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicBoolean;
 
 import de.measite.minidns.Client;
@@ -156,11 +144,6 @@ public class KeychainService extends Service implements Progressable {
     // this attribute can possibly merged with the one above? not sure...
     private AtomicBoolean mActionCanceled = new AtomicBoolean(false);
 
-
-    private KeyImportAccumulator mKeyImportAccumulator;
-
-    private KeychainService mKeychainService;
-
     @Override
     public IBinder onBind(Intent intent) {
         return null;
@@ -171,7 +154,6 @@ public class KeychainService extends Service implements Progressable {
      */
     @Override
     public int onStartCommand(final Intent intent, int flags, int startId) {
-        mKeychainService = this;
 
         if (ACTION_CANCEL.equals(intent.getAction())) {
             mActionCanceled.set(true);
@@ -208,7 +190,7 @@ public class KeychainService extends Service implements Progressable {
 
                 Log.logDebugBundle(data, "EXTRA_DATA");
 
-                ProviderHelper providerHelper = new ProviderHelper(mKeychainService);
+                ProviderHelper providerHelper = new ProviderHelper(KeychainService.this);
 
                 String action = intent.getAction();
 
@@ -219,9 +201,9 @@ public class KeychainService extends Service implements Progressable {
                         // Operation
                         ConsolidateResult result;
                         if (data.containsKey(CONSOLIDATE_RECOVERY) && data.getBoolean(CONSOLIDATE_RECOVERY)) {
-                            result = providerHelper.consolidateDatabaseStep2(mKeychainService);
+                            result = providerHelper.consolidateDatabaseStep2(KeychainService.this);
                         } else {
-                            result = providerHelper.consolidateDatabaseStep1(mKeychainService);
+                            result = providerHelper.consolidateDatabaseStep1(KeychainService.this);
                         }
 
                         // Result
@@ -284,8 +266,8 @@ public class KeychainService extends Service implements Progressable {
                                 }
                             }
 
-                            PgpDecryptVerify op = new PgpDecryptVerify(mKeychainService, providerHelper,
-                                    mKeychainService);
+                            PgpDecryptVerify op = new PgpDecryptVerify(KeychainService.this, providerHelper,
+                                    KeychainService.this);
 
                             PgpDecryptVerifyInputParcel input = new PgpDecryptVerifyInputParcel(messageBytes)
                                     .setSignedLiteralData(true)
@@ -330,7 +312,7 @@ public class KeychainService extends Service implements Progressable {
                         boolean isSecret = data.getBoolean(DELETE_IS_SECRET);
 
                         // Operation
-                        DeleteOperation op = new DeleteOperation(mKeychainService, providerHelper, mKeychainService);
+                        DeleteOperation op = new DeleteOperation(KeychainService.this, providerHelper, KeychainService.this);
                         DeleteResult result = op.execute(masterKeyIds, isSecret);
 
                         // Result
@@ -345,8 +327,8 @@ public class KeychainService extends Service implements Progressable {
                         CryptoInputParcel cryptoInput = data.getParcelable(EXTRA_CRYPTO_INPUT);
 
                         // Operation
-                        EditKeyOperation op = new EditKeyOperation(mKeychainService, providerHelper,
-                                mKeychainService, mActionCanceled);
+                        EditKeyOperation op = new EditKeyOperation(KeychainService.this, providerHelper,
+                                KeychainService.this, mActionCanceled);
                         OperationResult result = op.execute(saveParcel, cryptoInput);
 
                         // Result
@@ -363,7 +345,7 @@ public class KeychainService extends Service implements Progressable {
 
                         // Operation
                         PromoteKeyOperation op = new PromoteKeyOperation(
-                                mKeychainService, providerHelper, mKeychainService,
+                                KeychainService.this, providerHelper, KeychainService.this,
                                 mActionCanceled);
                         PromoteKeyResult result = op.execute(keyRingId, cardAid, subKeyIds);
 
@@ -384,7 +366,7 @@ public class KeychainService extends Service implements Progressable {
 
                         // Operation
                         ImportExportOperation importExportOperation = new ImportExportOperation(
-                                mKeychainService, providerHelper, mKeychainService);
+                                KeychainService.this, providerHelper, KeychainService.this);
                         ExportResult result;
                         if (outputFile != null) {
                             result = importExportOperation.exportToFile(masterKeyIds, exportSecret, outputFile);
@@ -403,23 +385,16 @@ public class KeychainService extends Service implements Progressable {
                         String keyServer = data.getString(IMPORT_KEY_SERVER);
                         ArrayList<ParcelableKeyRing> keyList = data.getParcelableArrayList(IMPORT_KEY_LIST);
 
-                        // either keyList or cache must be null, no guarantees otherwise
-                        if (keyList == null) {// import from file, do serially
-                            serialKeyImport(null, keyServer, providerHelper);
-                        } else {
-                            // if there is more than one key with the same fingerprint, we do a serial import to prevent
-                            // https://github.com/open-keychain/open-keychain/issues/1221
-                            HashSet<String> keyFingerprintSet = new HashSet<>();
-                            for (int i = 0; i < keyList.size(); i++) {
-                                keyFingerprintSet.add(keyList.get(i).mExpectedFingerprint);
-                            }
-                            if (keyFingerprintSet.size() == keyList.size()) {
-                                // all keys have unique fingerprints
-                                multiThreadedKeyImport(keyList.iterator(), keyList.size(), keyServer);
-                            } else {
-                                serialKeyImport(keyList, keyServer, providerHelper);
-                            }
-                        }
+                        ImportExportOperation importExportOperation = new ImportExportOperation(
+                                KeychainService.this,
+                                providerHelper, KeychainService.this, mActionCanceled);
+
+                        ImportKeyringParcel inputParcel = new ImportKeyringParcel(keyList, keyServer);
+                        CryptoInputParcel cryptoInputParcel = new CryptoInputParcel();
+
+                        ImportKeyResult result = importExportOperation.execute(inputParcel, cryptoInputParcel);
+
+                        sendMessageToHandler(MessageStatus.OKAY, result);
 
                         break;
                     }
@@ -434,8 +409,8 @@ public class KeychainService extends Service implements Progressable {
                             HkpKeyserver server = new HkpKeyserver(keyServer);
 
                             CanonicalizedPublicKeyRing keyring = providerHelper.getCanonicalizedPublicKeyRing(dataUri);
-                            ImportExportOperation importExportOperation = new ImportExportOperation(mKeychainService,
-                                    providerHelper, mKeychainService);
+                            ImportExportOperation importExportOperation = new ImportExportOperation(
+                                    KeychainService.this, providerHelper, KeychainService.this);
 
                             try {
                                 importExportOperation.uploadKeyRingToServer(server, keyring);
@@ -450,16 +425,13 @@ public class KeychainService extends Service implements Progressable {
                         break;
                     }
                 }
-                if (!intent.getAction().equals(ACTION_IMPORT_KEYRING)) {
-                    // import keyring handles stopping service on its own
-                    stopSelf();
-                }
+                stopSelf();
             }
         };
 
         Thread actionThread = new Thread(actionRunnable);
         actionThread.start();
-        
+
         return START_NOT_STICKY;
     }
 
@@ -484,7 +456,7 @@ public class KeychainService extends Service implements Progressable {
         // contextualize the exception, if necessary
         String message;
         if (e instanceof PgpGeneralMsgIdException) {
-            e = ((PgpGeneralMsgIdException) e).getContextualized(mKeychainService);
+            e = ((PgpGeneralMsgIdException) e).getContextualized(KeychainService.this);
             message = e.getMessage();
         } else {
             message = e.getMessage();
@@ -563,215 +535,4 @@ public class KeychainService extends Service implements Progressable {
     public void setPreventCancel() {
         sendMessageToHandler(MessageStatus.PREVENT_CANCEL);
     }
-
-    public void serialKeyImport(ArrayList<ParcelableKeyRing> keyList, final String keyServer,
-                                ProviderHelper providerHelper) {
-        Log.d(Constants.TAG, "serial key import starting");
-        ParcelableFileCache<ParcelableKeyRing> cache =
-                new ParcelableFileCache<>(mKeychainService, "key_import.pcl");
-
-        // Operation
-        ImportExportOperation importExportOperation = new ImportExportOperation(
-                mKeychainService, providerHelper, mKeychainService,
-                mActionCanceled);
-        // Either list or cache must be null, no guarantees otherwise.
-        ImportKeyResult result = keyList != null
-                ? importExportOperation.importKeyRings(keyList, keyServer)
-                : importExportOperation.importKeyRings(cache, keyServer);
-
-        ContactSyncAdapterService.requestSync();
-        // Result
-        sendMessageToHandler(MessageStatus.OKAY, result);
-
-        stopSelf();
-    }
-
-    public void multiThreadedKeyImport(Iterator<ParcelableKeyRing> keyListIterator, int totKeys, final String
-            keyServer) {
-        Log.d(Constants.TAG, "Multi-threaded key import starting");
-        if (keyListIterator != null) {
-            mKeyImportAccumulator = new KeyImportAccumulator(totKeys, mKeychainService);
-            setProgress(0, totKeys);
-
-            final int maxThreads = 200;
-            ExecutorService importExecutor = new ThreadPoolExecutor(0, maxThreads,
-                    30L, TimeUnit.SECONDS,
-                    new SynchronousQueue<Runnable>());
-
-            while (keyListIterator.hasNext()) {
-
-                final ParcelableKeyRing pkRing = keyListIterator.next();
-
-                Runnable importOperationRunnable = new Runnable() {
-
-                    @Override
-                    public void run() {
-                        ImportKeyResult result = null;
-                        try {
-                            ImportExportOperation importExportOperation = new ImportExportOperation(
-                                    mKeychainService,
-                                    new ProviderHelper(mKeychainService),
-                                    mKeyImportAccumulator.getImportProgressable(),
-                                    mActionCanceled);
-
-                            ArrayList<ParcelableKeyRing> list = new ArrayList<>();
-                            list.add(pkRing);
-
-                            result = importExportOperation.importKeyRings(list,
-                                    keyServer);
-                        } finally {
-                            // in the off-chance that importKeyRings does something to crash the
-                            // thread before it can call singleKeyRingImportCompleted, our imported
-                            // key count will go wrong. This will cause the service to never die,
-                            // and the progress dialog to stay displayed. The finally block was
-                            // originally meant to ensure singleKeyRingImportCompleted was called,
-                            // and checks for null were to be introduced, but in such a scenario,
-                            // knowing an uncaught error exists in importKeyRings is more important.
-
-                            // if a null gets passed, something wrong is happening. We want a crash.
-
-                            mKeyImportAccumulator.singleKeyRingImportCompleted(result);
-                        }
-                    }
-                };
-
-                importExecutor.execute(importOperationRunnable);
-            }
-        }
-    }
-
-    /**
-     * Used to accumulate the results of individual key imports
-     */
-    private class KeyImportAccumulator {
-        private OperationResult.OperationLog mImportLog = new OperationResult.OperationLog();
-        private int mTotalKeys;
-        private int mImportedKeys = 0;
-        private Progressable mInternalProgressable;
-        ArrayList<Long> mImportedMasterKeyIds = new ArrayList<Long>();
-        private int mBadKeys = 0;
-        private int mNewKeys = 0;
-        private int mUpdatedKeys = 0;
-        private int mSecret = 0;
-        private int mResultType = 0;
-
-        /**
-         * meant to be used with a service due to stopSelf() in singleKeyRingImportCompleted. Remove this if
-         * generalising.
-         *
-         * @param totalKeys            total number of keys to be imported
-         * @param externalProgressable the external progressable to be updated every time a key is imported
-         */
-        public KeyImportAccumulator(int totalKeys, Progressable externalProgressable) {
-            mTotalKeys = totalKeys;
-            // ignore updates from ImportExportOperation for now
-            mInternalProgressable = new Progressable() {
-                @Override
-                public void setProgress(String message, int current, int total) {
-
-                }
-
-                @Override
-                public void setProgress(int resourceId, int current, int total) {
-
-                }
-
-                @Override
-                public void setProgress(int current, int total) {
-
-                }
-
-                @Override
-                public void setPreventCancel() {
-
-                }
-            };
-        }
-
-        private synchronized void singleKeyRingImportCompleted(ImportKeyResult result) {
-            // increase imported key count and accumulate log and bad, new etc. key counts from result
-            mKeyImportAccumulator.accumulateKeyImport(result);
-
-            setProgress(mKeyImportAccumulator.getImportedKeys(), mKeyImportAccumulator.getTotalKeys());
-
-            if (mKeyImportAccumulator.isImportFinished()) {
-                ContactSyncAdapterService.requestSync();
-
-                sendMessageToHandler(ServiceProgressHandler.MessageStatus.OKAY,
-                        mKeyImportAccumulator.getConsolidatedImportKeyResult());
-
-                stopSelf();//we're done here
-            }
-        }
-
-        public Progressable getImportProgressable() {
-            return mInternalProgressable;
-        }
-
-        public int getTotalKeys() {
-            return mTotalKeys;
-        }
-
-        public int getImportedKeys() {
-            return mImportedKeys;
-        }
-
-        public synchronized void accumulateKeyImport(ImportKeyResult result) {
-            mImportedKeys++;
-            mImportLog.addAll(result.getLog().toList());//accumulates log
-            mBadKeys += result.mBadKeys;
-            mNewKeys += result.mNewKeys;
-            mUpdatedKeys += result.mUpdatedKeys;
-            mSecret += result.mSecret;
-
-            long[] masterKeyIds = result.getImportedMasterKeyIds();
-            for (long masterKeyId : masterKeyIds) {
-                mImportedMasterKeyIds.add(masterKeyId);
-            }
-
-            // if any key import has been cancelled, set result type to cancelled
-            // resultType is added to in getConsolidatedKayImport to account for remaining factors
-            mResultType |= result.getResult() & ImportKeyResult.RESULT_CANCELLED;
-        }
-
-        /**
-         * returns accumulated result of all imports so far
-         */
-        public ImportKeyResult getConsolidatedImportKeyResult() {
-
-            // adding required information to mResultType
-            // special case,no keys requested for import
-            if (mBadKeys == 0 && mNewKeys == 0 && mUpdatedKeys == 0) {
-                mResultType = ImportKeyResult.RESULT_FAIL_NOTHING;
-            } else {
-                if (mNewKeys > 0) {
-                    mResultType |= ImportKeyResult.RESULT_OK_NEWKEYS;
-                }
-                if (mUpdatedKeys > 0) {
-                    mResultType |= ImportKeyResult.RESULT_OK_UPDATED;
-                }
-                if (mBadKeys > 0) {
-                    mResultType |= ImportKeyResult.RESULT_WITH_ERRORS;
-                    if (mNewKeys == 0 && mUpdatedKeys == 0) {
-                        mResultType |= ImportKeyResult.RESULT_ERROR;
-                    }
-                }
-                if (mImportLog.containsWarnings()) {
-                    mResultType |= ImportKeyResult.RESULT_WARNINGS;
-                }
-            }
-
-            long masterKeyIds[] = new long[mImportedMasterKeyIds.size()];
-            for (int i = 0; i < masterKeyIds.length; i++) {
-                masterKeyIds[i] = mImportedMasterKeyIds.get(i);
-            }
-
-            return new ImportKeyResult(mResultType, mImportLog, mNewKeys, mUpdatedKeys, mBadKeys,
-                    mSecret, masterKeyIds);
-        }
-
-        public boolean isImportFinished() {
-            return mTotalKeys == mImportedKeys;
-        }
-    }
-}
+}
\ No newline at end of file
diff --git a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/service/ServiceProgressHandler.java b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/service/ServiceProgressHandler.java
index 989b0c4bd..d294e5057 100644
--- a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/service/ServiceProgressHandler.java
+++ b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/service/ServiceProgressHandler.java
@@ -64,6 +64,8 @@ public class ServiceProgressHandler extends Handler {
     public static final String KEYBASE_PRESENCE_URL = "keybase_presence_url";
     public static final String KEYBASE_PRESENCE_LABEL = "keybase_presence_label";
 
+    public static final String TAG_PROGRESS_DIALOG = "progressDialog";
+
     FragmentActivity mActivity;
 
     public ServiceProgressHandler(FragmentActivity activity) {
@@ -88,7 +90,7 @@ public class ServiceProgressHandler extends Handler {
         Handler handler = new Handler();
         handler.post(new Runnable() {
             public void run() {
-                frag.show(manager, "progressDialog");
+                frag.show(manager, TAG_PROGRESS_DIALOG);
             }
         });
 
diff --git a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/ImportKeysActivity.java b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/ImportKeysActivity.java
index 07ab88b02..b05cc6f50 100644
--- a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/ImportKeysActivity.java
+++ b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/ImportKeysActivity.java
@@ -17,12 +17,10 @@
 
 package org.sufficientlysecure.keychain.ui;
 
-import android.app.ProgressDialog;
 import android.content.Intent;
 import android.net.Uri;
 import android.os.Bundle;
 import android.os.Message;
-import android.os.Messenger;
 import android.support.v4.app.Fragment;
 import android.view.View;
 import android.view.View.OnClickListener;
@@ -35,9 +33,10 @@ import org.sufficientlysecure.keychain.keyimport.ImportKeysListEntry;
 import org.sufficientlysecure.keychain.keyimport.ParcelableKeyRing;
 import org.sufficientlysecure.keychain.operations.results.ImportKeyResult;
 import org.sufficientlysecure.keychain.operations.results.OperationResult;
-import org.sufficientlysecure.keychain.service.KeychainService;
+import org.sufficientlysecure.keychain.service.ImportKeyringParcel;
 import org.sufficientlysecure.keychain.ui.base.BaseNfcActivity;
 import org.sufficientlysecure.keychain.service.ServiceProgressHandler;
+import org.sufficientlysecure.keychain.ui.base.CryptoOperationHelper;
 import org.sufficientlysecure.keychain.ui.util.KeyFormattingUtils;
 import org.sufficientlysecure.keychain.ui.util.Notify;
 import org.sufficientlysecure.keychain.util.Log;
@@ -47,7 +46,8 @@ import org.sufficientlysecure.keychain.util.ParcelableFileCache.IteratorWithSize
 import java.io.IOException;
 import java.util.ArrayList;
 
-public class ImportKeysActivity extends BaseNfcActivity {
+public class ImportKeysActivity extends BaseNfcActivity
+        implements CryptoOperationHelper.Callback<ImportKeyringParcel, ImportKeyResult> {
 
     public static final String ACTION_IMPORT_KEY = OpenKeychainIntents.IMPORT_KEY;
     public static final String ACTION_IMPORT_KEY_FROM_KEYSERVER = OpenKeychainIntents.IMPORT_KEY_FROM_KEYSERVER;
@@ -82,6 +82,12 @@ public class ImportKeysActivity extends BaseNfcActivity {
     private Fragment mTopFragment;
     private View mImportButton;
 
+    // for CryptoOperationHelper.Callback
+    private String mKeyserver;
+    private ArrayList<ParcelableKeyRing> mKeyList;
+
+    private CryptoOperationHelper<ImportKeyringParcel, ImportKeyResult> mOperationHelper;
+
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
@@ -388,23 +394,9 @@ public class ImportKeysActivity extends BaseNfcActivity {
             return;
         }
 
-        ServiceProgressHandler serviceHandler = new ServiceProgressHandler(this) {
-            @Override
-            public void handleMessage(Message message) {
-                // handle messages by standard KeychainIntentServiceHandler first
-                super.handleMessage(message);
-
-                ImportKeysActivity.this.handleMessage(message);
-            }
-        };
-
-        // Send all information needed to service to import key in other thread
-        Intent intent = new Intent(this, KeychainService.class);
-
-        intent.setAction(KeychainService.ACTION_IMPORT_KEYRING);
-
-        // fill values for this action
-        Bundle data = new Bundle();
+        mOperationHelper = new CryptoOperationHelper<ImportKeyringParcel, ImportKeyResult>(
+                this, this, R.string.progress_importing
+        );
 
         ImportKeysListFragment.LoaderState ls = mListFragment.getLoaderState();
         if (ls instanceof ImportKeysListFragment.BytesLoaderState) {
@@ -423,30 +415,18 @@ public class ImportKeysActivity extends BaseNfcActivity {
                         new ParcelableFileCache<>(this, "key_import.pcl");
                 cache.writeCache(selectedEntries);
 
-                intent.putExtra(KeychainService.EXTRA_DATA, data);
-
-                // Create a new Messenger for the communication back
-                Messenger messenger = new Messenger(serviceHandler);
-                intent.putExtra(KeychainService.EXTRA_MESSENGER, messenger);
+                mKeyList = null;
+                mKeyserver = null;
+                mOperationHelper.cryptoOperation();
 
-                // show progress dialog
-                serviceHandler.showProgressDialog(
-                        getString(R.string.progress_importing),
-                        ProgressDialog.STYLE_HORIZONTAL,
-                        true
-                );
-
-                // start service with intent
-                startService(intent);
             } catch (IOException e) {
                 Log.e(Constants.TAG, "Problem writing cache file", e);
                 Notify.create(this, "Problem writing cache file!", Notify.Style.ERROR)
                         .show((ViewGroup) findViewById(R.id.import_snackbar));
             }
         } else if (ls instanceof ImportKeysListFragment.CloudLoaderState) {
-            ImportKeysListFragment.CloudLoaderState sls = (ImportKeysListFragment.CloudLoaderState) ls;
-
-            data.putString(KeychainService.IMPORT_KEY_SERVER, sls.mCloudPrefs.keyserver);
+            ImportKeysListFragment.CloudLoaderState sls =
+                    (ImportKeysListFragment.CloudLoaderState) ls;
 
             // get selected key entries
             ArrayList<ParcelableKeyRing> keys = new ArrayList<>();
@@ -459,22 +439,11 @@ public class ImportKeysActivity extends BaseNfcActivity {
                     );
                 }
             }
-            data.putParcelableArrayList(KeychainService.IMPORT_KEY_LIST, keys);
-
-            intent.putExtra(KeychainService.EXTRA_DATA, data);
 
-            // Create a new Messenger for the communication back
-            Messenger messenger = new Messenger(serviceHandler);
-            intent.putExtra(KeychainService.EXTRA_MESSENGER, messenger);
+            mKeyList = keys;
+            mKeyserver = sls.mCloudPrefs.keyserver;
+            mOperationHelper.cryptoOperation();
 
-            // show progress dialog
-            serviceHandler.showProgressDialog(
-                    getString(R.string.progress_importing),
-                    ProgressDialog.STYLE_HORIZONTAL, true
-            );
-
-            // start service with intent
-            startService(intent);
         }
     }
 
@@ -485,4 +454,52 @@ public class ImportKeysActivity extends BaseNfcActivity {
         // either way, finish afterwards
         finish();
     }
+
+    @Override
+    public void onActivityResult(int requestCode, int resultCode, Intent data) {
+        if (mOperationHelper == null ||
+                !mOperationHelper.handleActivityResult(requestCode, resultCode, data)) {
+            super.onActivityResult(requestCode, resultCode, data);
+        }
+    }
+
+    public void handleResult (ImportKeyResult result) {
+        if (ACTION_IMPORT_KEY_FROM_KEYSERVER_AND_RETURN_RESULT.equals(getIntent().getAction())
+                || ACTION_IMPORT_KEY_FROM_FILE_AND_RETURN.equals(getIntent().getAction())) {
+            Intent intent = new Intent();
+            intent.putExtra(ImportKeyResult.EXTRA_RESULT, result);
+            ImportKeysActivity.this.setResult(RESULT_OK, intent);
+            ImportKeysActivity.this.finish();
+            return;
+        }
+        if (ACTION_IMPORT_KEY_FROM_KEYSERVER_AND_RETURN_TO_SERVICE.equals(getIntent().getAction())) {
+            ImportKeysActivity.this.setResult(RESULT_OK, mPendingIntentData);
+            ImportKeysActivity.this.finish();
+            return;
+        }
+
+        result.createNotify(ImportKeysActivity.this)
+                .show((ViewGroup) findViewById(R.id.import_snackbar));
+    }
+    // methods from CryptoOperationHelper.Callback
+
+    @Override
+    public ImportKeyringParcel createOperationInput() {
+        return new ImportKeyringParcel(mKeyList, mKeyserver);
+    }
+
+    @Override
+    public void onCryptoOperationSuccess(ImportKeyResult result) {
+        handleResult(result);
+    }
+
+    @Override
+    public void onCryptoOperationCancelled() {
+        // do nothing
+    }
+
+    @Override
+    public void onCryptoOperationError(ImportKeyResult result) {
+        handleResult(result);
+    }
 }
diff --git a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/base/CryptoOperationFragment.java b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/base/CryptoOperationFragment.java
index 764602735..c00ebd915 100644
--- a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/base/CryptoOperationFragment.java
+++ b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/base/CryptoOperationFragment.java
@@ -18,185 +18,66 @@
 
 package org.sufficientlysecure.keychain.ui.base;
 
-import android.app.Activity;
-import android.app.ProgressDialog;
 import android.content.Intent;
-import android.os.Bundle;
-import android.os.Message;
-import android.os.Messenger;
 import android.os.Parcelable;
 import android.support.v4.app.Fragment;
 
-import org.sufficientlysecure.keychain.R;
-import org.sufficientlysecure.keychain.operations.results.InputPendingResult;
 import org.sufficientlysecure.keychain.operations.results.OperationResult;
-import org.sufficientlysecure.keychain.service.KeychainNewService;
-import org.sufficientlysecure.keychain.service.KeychainService;
-import org.sufficientlysecure.keychain.service.ServiceProgressHandler;
 import org.sufficientlysecure.keychain.service.input.CryptoInputParcel;
-import org.sufficientlysecure.keychain.service.input.RequiredInputParcel;
-import org.sufficientlysecure.keychain.ui.NfcOperationActivity;
-import org.sufficientlysecure.keychain.ui.PassphraseDialogActivity;
-import org.sufficientlysecure.keychain.ui.dialog.ProgressDialogFragment;
 
 
 /**
  * All fragments executing crypto operations need to extend this class.
  */
-public abstract class CryptoOperationFragment <T extends Parcelable, S extends OperationResult>
+public abstract class CryptoOperationFragment<T extends Parcelable, S extends OperationResult>
         extends Fragment {
 
-    public static final int REQUEST_CODE_PASSPHRASE = 0x00008001;
-    public static final int REQUEST_CODE_NFC = 0x00008002;
+    private CryptoOperationHelper<T, S> mOperationHelper;
 
-    private void initiateInputActivity(RequiredInputParcel requiredInput) {
+    public CryptoOperationFragment() {
+        // this is implemented here instead of by the fragment so that the corresponding methods in
+        // CryptoOperationFragment may continue using the "protected" modifier.
+        CryptoOperationHelper.Callback callback = new CryptoOperationHelper.Callback<T, S>() {
 
-        switch (requiredInput.mType) {
-            case NFC_KEYTOCARD:
-            case NFC_DECRYPT:
-            case NFC_SIGN: {
-                Intent intent = new Intent(getActivity(), NfcOperationActivity.class);
-                intent.putExtra(NfcOperationActivity.EXTRA_REQUIRED_INPUT, requiredInput);
-                startActivityForResult(intent, REQUEST_CODE_NFC);
-                return;
+            @Override
+            public T createOperationInput() {
+                return CryptoOperationFragment.this.createOperationInput();
             }
 
-            case PASSPHRASE:
-            case PASSPHRASE_SYMMETRIC: {
-                Intent intent = new Intent(getActivity(), PassphraseDialogActivity.class);
-                intent.putExtra(PassphraseDialogActivity.EXTRA_REQUIRED_INPUT, requiredInput);
-                startActivityForResult(intent, REQUEST_CODE_PASSPHRASE);
-                return;
+            @Override
+            public void onCryptoOperationSuccess(S result) {
+                CryptoOperationFragment.this.onCryptoOperationSuccess(result);
             }
-        }
-
-        throw new RuntimeException("Unhandled pending result!");
-    }
 
-    @Override
-    public void onActivityResult(int requestCode, int resultCode, Intent data) {
-        if (resultCode == Activity.RESULT_CANCELED) {
-            onCryptoOperationCancelled();
-            return;
-        }
-
-        switch (requestCode) {
-            case REQUEST_CODE_PASSPHRASE: {
-                if (resultCode == Activity.RESULT_OK && data != null) {
-                    CryptoInputParcel cryptoInput =
-                            data.getParcelableExtra(PassphraseDialogActivity.RESULT_CRYPTO_INPUT);
-                    cryptoOperation(cryptoInput);
-                    return;
-                }
-                break;
+            @Override
+            public void onCryptoOperationCancelled() {
+                CryptoOperationFragment.this.onCryptoOperationCancelled();
             }
 
-            case REQUEST_CODE_NFC: {
-                if (resultCode == Activity.RESULT_OK && data != null) {
-                    CryptoInputParcel cryptoInput =
-                            data.getParcelableExtra(NfcOperationActivity.RESULT_DATA);
-                    cryptoOperation(cryptoInput);
-                    return;
-                }
-                break;
+            @Override
+            public void onCryptoOperationError(S result) {
+                CryptoOperationFragment.this.onCryptoOperationError(result);
             }
+        };
 
-            default: {
-                super.onActivityResult(requestCode, resultCode, data);
-            }
-        }
+        mOperationHelper = new CryptoOperationHelper<>(this, callback);
     }
 
-    protected void dismissProgress() {
-
-        ProgressDialogFragment progressDialogFragment =
-                (ProgressDialogFragment) getFragmentManager().findFragmentByTag("progressDialog");
-
-        if (progressDialogFragment == null) {
-            return;
-        }
-
-        progressDialogFragment.dismissAllowingStateLoss();
-
+    @Override
+    public void onActivityResult(int requestCode, int resultCode, Intent data) {
+        mOperationHelper.handleActivityResult(requestCode, resultCode, data);
     }
 
     protected abstract T createOperationInput();
 
-    protected void cryptoOperation(CryptoInputParcel cryptoInput) {
-        cryptoOperation(cryptoInput, true);
-    }
-
     protected void cryptoOperation() {
         cryptoOperation(new CryptoInputParcel());
     }
 
-    protected void cryptoOperation(CryptoInputParcel cryptoInput, boolean showProgress) {
-
-        T operationInput = createOperationInput();
-        if (operationInput == null) {
-            return;
-        }
-
-        // Send all information needed to service to edit key in other thread
-        Intent intent = new Intent(getActivity(), KeychainNewService.class);
-
-        intent.putExtra(KeychainNewService.EXTRA_OPERATION_INPUT, operationInput);
-        intent.putExtra(KeychainNewService.EXTRA_CRYPTO_INPUT, cryptoInput);
-
-        ServiceProgressHandler saveHandler = new ServiceProgressHandler(getActivity()) {
-            @Override
-            public void handleMessage(Message message) {
-                // handle messages by standard KeychainIntentServiceHandler first
-                super.handleMessage(message);
-
-                if (message.arg1 == MessageStatus.OKAY.ordinal()) {
-
-                    // get returned data bundle
-                    Bundle returnData = message.getData();
-                    if (returnData == null) {
-                        return;
-                    }
-
-                    final OperationResult result =
-                            returnData.getParcelable(OperationResult.EXTRA_RESULT);
-
-                    onHandleResult(result);
-                }
-            }
-
-            @Override
-            protected void onSetProgress(String msg, int progress, int max) {
-                // allow handling of progress in fragment, or delegate upwards
-                if ( ! onCryptoSetProgress(msg, progress, max)) {
-                    super.onSetProgress(msg, progress, max);
-                }
-            }
-        };
-
-        // Create a new Messenger for the communication back
-        Messenger messenger = new Messenger(saveHandler);
-        intent.putExtra(KeychainService.EXTRA_MESSENGER, messenger);
-
-        if (showProgress) {
-            saveHandler.showProgressDialog(
-                    getString(R.string.progress_building_key),
-                    ProgressDialog.STYLE_HORIZONTAL, false);
-        }
-
-        getActivity().startService(intent);
-
-    }
-
-    protected void onCryptoOperationResult(S result) {
-        if (result.success()) {
-            onCryptoOperationSuccess(result);
-        } else {
-            onCryptoOperationError(result);
-        }
+    protected void cryptoOperation(CryptoInputParcel cryptoInput) {
+        mOperationHelper.cryptoOperation(cryptoInput);
     }
 
-    abstract protected void onCryptoOperationSuccess(S result);
-
     protected void onCryptoOperationError(S result) {
         result.createNotify(getActivity()).show();
     }
@@ -204,31 +85,9 @@ public abstract class CryptoOperationFragment <T extends Parcelable, S extends O
     protected void onCryptoOperationCancelled() {
     }
 
-    public void onHandleResult(OperationResult result) {
-
-        if (result instanceof InputPendingResult) {
-            InputPendingResult pendingResult = (InputPendingResult) result;
-            if (pendingResult.isPending()) {
-                RequiredInputParcel requiredInput = pendingResult.getRequiredInputParcel();
-                initiateInputActivity(requiredInput);
-                return;
-            }
-        }
-
-        dismissProgress();
-
-        try {
-            // noinspection unchecked, because type erasure :(
-            onCryptoOperationResult((S) result);
-        } catch (ClassCastException e) {
-            throw new AssertionError("bad return class ("
-                    + result.getClass().getSimpleName() + "), this is a programming error!");
-        }
-
-    }
+    abstract protected void onCryptoOperationSuccess(S result);
 
-    protected boolean onCryptoSetProgress(String msg, int progress, int max) {
-        return false;
+    protected void onCryptoOperationResult(S result) {
+        mOperationHelper.onCryptoOperationResult(result);
     }
-
 }
diff --git a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/base/CryptoOperationHelper.java b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/base/CryptoOperationHelper.java
new file mode 100644
index 000000000..ffbda330e
--- /dev/null
+++ b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/base/CryptoOperationHelper.java
@@ -0,0 +1,307 @@
+/*
+ * Copyright (C) 2015 Dominik Schürmann <dominik@dominikschuermann.de>
+ * Copyright (C) 2015 Vincent Breitmoser <v.breitmoser@mugenguild.com>
+ * Copyright (C) 2015 Adithya Abraham Philip <adithyaphilip@gmail.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package org.sufficientlysecure.keychain.ui.base;
+
+import android.app.Activity;
+import android.app.ProgressDialog;
+import android.content.Intent;
+import android.os.Bundle;
+import android.os.Message;
+import android.os.Messenger;
+import android.os.Parcelable;
+import android.support.v4.app.Fragment;
+import android.support.v4.app.FragmentActivity;
+
+import android.support.v4.app.FragmentManager;
+import org.sufficientlysecure.keychain.R;
+import org.sufficientlysecure.keychain.operations.results.InputPendingResult;
+import org.sufficientlysecure.keychain.operations.results.OperationResult;
+import org.sufficientlysecure.keychain.service.KeychainNewService;
+import org.sufficientlysecure.keychain.service.KeychainService;
+import org.sufficientlysecure.keychain.service.ServiceProgressHandler;
+import org.sufficientlysecure.keychain.service.input.CryptoInputParcel;
+import org.sufficientlysecure.keychain.service.input.RequiredInputParcel;
+import org.sufficientlysecure.keychain.ui.NfcOperationActivity;
+import org.sufficientlysecure.keychain.ui.PassphraseDialogActivity;
+import org.sufficientlysecure.keychain.ui.dialog.ProgressDialogFragment;
+import org.sufficientlysecure.keychain.util.Log;
+
+/**
+ * Designed to be integrated into activities or fragments used for CryptoOperations.
+ * Encapsulates the execution of a crypto operation and handling of input pending cases.s
+ *
+ * @param <T> The type of input parcel sent to the operation
+ * @param <S> The type of result returned by the operation
+ */
+public class CryptoOperationHelper<T extends Parcelable, S extends OperationResult> {
+
+    public interface Callback <T extends Parcelable, S extends  OperationResult> {
+        T createOperationInput();
+        void onCryptoOperationSuccess(S result);
+        void onCryptoOperationCancelled();
+        void onCryptoOperationError(S result);
+    }
+
+    public static final int REQUEST_CODE_PASSPHRASE = 0x00008001;
+    public static final int REQUEST_CODE_NFC = 0x00008002;
+
+    // keeps track of request code used to start an activity from this CryptoOperationHelper.
+    // this is necessary when multiple CryptoOperationHelpers are used in the same fragment/activity
+    // otherwise all CryptoOperationHandlers may respond to the same onActivityResult
+    private int mRequestedCode = -1;
+
+    private int mProgressMessageString;
+
+    private FragmentActivity mActivity;
+    private Fragment mFragment;
+    private Callback<T, S> mCallback;
+
+    private boolean mUseFragment; // short hand for mActivity == null
+
+    /**
+     * If OperationHelper is being integrated into an activity
+     *
+     * @param activity
+     */
+    public CryptoOperationHelper(FragmentActivity activity, Callback<T, S> callback, int progressMessageString) {
+        mActivity = activity;
+        mUseFragment = false;
+        mCallback = callback;
+        mProgressMessageString = progressMessageString;
+    }
+
+    /**
+     * if OperationHelper is being integrated into a fragment
+     *
+     * @param fragment
+     */
+    public CryptoOperationHelper(Fragment fragment, Callback<T, S> callback, int progressMessageString) {
+        mFragment = fragment;
+        mUseFragment = true;
+        mProgressMessageString = progressMessageString;
+        mCallback = callback;
+    }
+
+    /**
+     * if OperationHelper is being integrated into a fragment with default message for the progress dialog
+     *
+     * @param fragment
+     */
+    public CryptoOperationHelper(Fragment fragment, Callback<T, S> callback) {
+        mFragment = fragment;
+        mUseFragment = true;
+        mProgressMessageString = R.string.progress_building_key;
+        mCallback = callback;
+    }
+
+    private void initiateInputActivity(RequiredInputParcel requiredInput) {
+
+        Activity activity = mUseFragment ? mFragment.getActivity() : mActivity;
+
+        Log.d("PHILIP", "Initating input " + requiredInput.mType);
+        switch (requiredInput.mType) {
+            case NFC_KEYTOCARD:
+            case NFC_DECRYPT:
+            case NFC_SIGN: {
+                Intent intent = new Intent(activity, NfcOperationActivity.class);
+                intent.putExtra(NfcOperationActivity.EXTRA_REQUIRED_INPUT, requiredInput);
+                mRequestedCode = REQUEST_CODE_NFC;
+                if (mUseFragment) {
+                    mFragment.startActivityForResult(intent, mRequestedCode);
+                } else {
+                    mActivity.startActivityForResult(intent, mRequestedCode);
+                }
+                return;
+            }
+
+            case PASSPHRASE:
+            case PASSPHRASE_SYMMETRIC: {
+                Intent intent = new Intent(activity, PassphraseDialogActivity.class);
+                intent.putExtra(PassphraseDialogActivity.EXTRA_REQUIRED_INPUT, requiredInput);
+                mRequestedCode = REQUEST_CODE_PASSPHRASE;
+                if (mUseFragment) {
+                    mFragment.startActivityForResult(intent, mRequestedCode);
+                } else {
+                    mActivity.startActivityForResult(intent, mRequestedCode);
+                }
+                return;
+            }
+        }
+
+        throw new RuntimeException("Unhandled pending result!");
+    }
+
+    /**
+     * Attempts the result of an activity started by this helper. Returns true if requestCode is recognized,
+     * false otherwise.
+     *
+     * @param requestCode
+     * @param resultCode
+     * @param data
+     * @return true if requestCode was recognized, false otherwise
+     */
+    public boolean handleActivityResult(int requestCode, int resultCode, Intent data) {
+        Log.d("PHILIP", "received activity result in OperationHelper");
+
+        if (mRequestedCode != requestCode) {
+            // this wasn't meant for us to handle
+            return false;
+        } else {
+            mRequestedCode = -1;
+        }
+        if (resultCode == Activity.RESULT_CANCELED) {
+            mCallback.onCryptoOperationCancelled();
+            return true;
+        }
+
+        switch (requestCode) {
+            case REQUEST_CODE_PASSPHRASE: {
+                if (resultCode == Activity.RESULT_OK && data != null) {
+                    CryptoInputParcel cryptoInput =
+                            data.getParcelableExtra(PassphraseDialogActivity.RESULT_CRYPTO_INPUT);
+                    cryptoOperation(cryptoInput);
+                    return true;
+                }
+                break;
+            }
+
+            case REQUEST_CODE_NFC: {
+                if (resultCode == Activity.RESULT_OK && data != null) {
+                    CryptoInputParcel cryptoInput =
+                            data.getParcelableExtra(NfcOperationActivity.RESULT_DATA);
+                    cryptoOperation(cryptoInput);
+                    return true;
+                }
+                break;
+            }
+
+            default: {
+                return false;
+            }
+        }
+        return true;
+    }
+
+    protected void dismissProgress() {
+        FragmentManager fragmentManager =
+                mUseFragment ? mFragment.getFragmentManager() :
+                        mActivity.getSupportFragmentManager();
+
+        ProgressDialogFragment progressDialogFragment =
+                (ProgressDialogFragment) fragmentManager.findFragmentByTag(
+                        ServiceProgressHandler.TAG_PROGRESS_DIALOG);
+
+        if (progressDialogFragment == null) {
+            return;
+        }
+
+        progressDialogFragment.dismissAllowingStateLoss();
+
+    }
+
+    public void cryptoOperation(CryptoInputParcel cryptoInput) {
+
+        FragmentActivity activity = mUseFragment ? mFragment.getActivity() : mActivity;
+
+        T operationInput = mCallback.createOperationInput();
+        if (operationInput == null) {
+            return;
+        }
+
+        // Send all information needed to service to edit key in other thread
+        Intent intent = new Intent(activity, KeychainNewService.class);
+
+        intent.putExtra(KeychainNewService.EXTRA_OPERATION_INPUT, operationInput);
+        intent.putExtra(KeychainNewService.EXTRA_CRYPTO_INPUT, cryptoInput);
+
+        ServiceProgressHandler saveHandler = new ServiceProgressHandler(activity) {
+            @Override
+            public void handleMessage(Message message) {
+                // handle messages by standard KeychainIntentServiceHandler first
+                super.handleMessage(message);
+
+                if (message.arg1 == MessageStatus.OKAY.ordinal()) {
+
+                    // get returned data bundle
+                    Bundle returnData = message.getData();
+                    if (returnData == null) {
+                        return;
+                    }
+
+                    final OperationResult result =
+                            returnData.getParcelable(OperationResult.EXTRA_RESULT);
+
+                    onHandleResult(result);
+                }
+            }
+        };
+
+        saveHandler.showProgressDialog(
+                activity.getString(mProgressMessageString),
+                ProgressDialog.STYLE_HORIZONTAL, false);
+
+        // Create a new Messenger for the communication back
+        Messenger messenger = new Messenger(saveHandler);
+        intent.putExtra(KeychainService.EXTRA_MESSENGER, messenger);
+
+        activity.startService(intent);
+
+    }
+
+    public void cryptoOperation() {
+        cryptoOperation(new CryptoInputParcel());
+    }
+
+    protected void onCryptoOperationResult(S result) {
+        Log.d("PHILIP", "cryptoResult " + result.success());
+        if (result.success()) {
+            mCallback.onCryptoOperationSuccess(result);
+        } else {
+            mCallback.onCryptoOperationError(result);
+        }
+    }
+
+    public void onHandleResult(OperationResult result) {
+        Log.d("PHILIP", "Handling result in OperationHelper");
+
+        if (result instanceof InputPendingResult) {
+            Log.d("PHILIP", "is pending result");
+            InputPendingResult pendingResult = (InputPendingResult) result;
+            if (pendingResult.isPending()) {
+
+                Log.d("PHILIP", "Is pending");
+                RequiredInputParcel requiredInput = pendingResult.getRequiredInputParcel();
+                initiateInputActivity(requiredInput);
+                return;
+            }
+        }
+
+        dismissProgress();
+
+        try {
+            // noinspection unchecked, because type erasure :(
+            onCryptoOperationResult((S) result);
+        } catch (ClassCastException e) {
+            throw new AssertionError("bad return class ("
+                    + result.getClass().getSimpleName() + "), this is a programming error!");
+        }
+
+    }
+}
\ No newline at end of file