Merge pull request #2304 from open-keychain/autocrypt-setup-message

Autocrypt setup message format support

OpenKeychain/src/main/AndroidManifest.xml

@@ -454,6 +454,14 @@
                 <data android:pathPattern=".*\\..*\\..*\\..*\\..*\\..*\\..*\\..*\\..*\\.bin" />
                 <data android:pathPattern=".*\\..*\\..*\\..*\\..*\\..*\\..*\\..*\\..*\\..*\\.bin" />
             </intent-filter>
+            <intent-filter android:label="@string/intent_autocrypt_setup">
+                <action android:name="android.intent.action.VIEW" />
+
+                <category android:name="android.intent.category.DEFAULT" />
+                <category android:name="android.intent.category.BROWSABLE" />
+
+                <data android:mimeType="application/autocrypt-setup" />
+            </intent-filter>
         </activity>
         <activity
             android:name=".ui.UploadKeyActivity"

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/operations/BackupOperation.java

@@ -58,8 +58,10 @@ import org.sufficientlysecure.keychain.provider.TemporaryFileProvider;
 import org.sufficientlysecure.keychain.service.BackupKeyringParcel;
 import org.sufficientlysecure.keychain.service.input.CryptoInputParcel;
 import org.sufficientlysecure.keychain.ui.util.KeyFormattingUtils;
+import org.sufficientlysecure.keychain.util.Numeric9x4PassphraseUtil;
 import org.sufficientlysecure.keychain.util.CountingOutputStream;
 import org.sufficientlysecure.keychain.util.InputData;
+import org.sufficientlysecure.keychain.util.Passphrase;
 import timber.log.Timber;
 
 
@@ -127,8 +129,8 @@ public class BackupOperation extends BaseOperation<BackupKeyringParcel> {
             }
 
             CountingOutputStream outStream = new CountingOutputStream(new BufferedOutputStream(plainOut));
-            boolean backupSuccess = exportKeysToStream(
+            boolean backupSuccess = exportKeysToStream(log, backupInput.getMasterKeyIds(),
-                    log, backupInput.getMasterKeyIds(), backupInput.getExportSecret(), outStream);
+                    backupInput.getExportSecret(), backupInput.getExportPublic(), outStream);
 
             if (!backupSuccess) {
                 // if there was an error, it will be in the log so we just have to return
@@ -169,9 +171,15 @@ public class BackupOperation extends BaseOperation<BackupKeyringParcel> {
         PgpSignEncryptOperation signEncryptOperation = new PgpSignEncryptOperation(mContext, mKeyRepository, mProgressable, mCancelled);
 
         PgpSignEncryptData.Builder builder = PgpSignEncryptData.builder();
-        builder.setSymmetricPassphrase(cryptoInput.getPassphrase());
+        Passphrase passphrase = cryptoInput.getPassphrase();
+        builder.setSymmetricPassphrase(passphrase);
         builder.setEnableAsciiArmorOutput(backupInput.getEnableAsciiArmorOutput());
-        builder.setAddBackupHeader(true);
+        boolean isNumeric9x4Passphrase = passphrase != null && Numeric9x4PassphraseUtil.isNumeric9x4Passphrase(passphrase);
+        if (isNumeric9x4Passphrase) {
+            builder.setPassphraseFormat("numeric9x4");
+            char[] passphraseChars = passphrase.getCharArray();
+            builder.setPassphraseBegin("" + passphraseChars[0] + passphraseChars[1]);
+        }
         PgpSignEncryptData pgpSignEncryptData = builder.build();
 
         InputStream inStream = mContext.getContentResolver().openInputStream(plainUri);
@@ -206,7 +214,8 @@ public class BackupOperation extends BaseOperation<BackupKeyringParcel> {
                 pgpSignEncryptData, CryptoInputParcel.createCryptoInputParcel(), inputData, outStream);
     }
 
-    boolean exportKeysToStream(OperationLog log, long[] masterKeyIds, boolean exportSecret, OutputStream outStream) {
+    boolean exportKeysToStream(OperationLog log, long[] masterKeyIds, boolean exportSecret, boolean exportPublic,
+            OutputStream outStream) {
         // noinspection unused TODO use these in a log entry
         int okSecret = 0, okPublic = 0;
 
@@ -232,9 +241,15 @@ public class BackupOperation extends BaseOperation<BackupKeyringParcel> {
                 long masterKeyId = cursor.getLong(INDEX_MASTER_KEY_ID);
                 log.add(LogType.MSG_BACKUP_PUBLIC, 1, KeyFormattingUtils.beautifyKeyId(masterKeyId));
 
-                if (writePublicKeyToStream(masterKeyId, log, outStream)) {
+                boolean publicKeyWriteOk = false;
-                    okPublic += 1;
+                if (exportPublic) {
+                    publicKeyWriteOk = writePublicKeyToStream(masterKeyId, log, outStream);
+                    if (publicKeyWriteOk) {
+                        okPublic += 1;
+                    }
+                }
 
+                if (publicKeyWriteOk || !exportPublic) {
                     boolean hasSecret = cursor.getInt(INDEX_HAS_ANY_SECRET) > 0;
                     if (exportSecret && hasSecret) {
                         log.add(LogType.MSG_BACKUP_SECRET, 2, KeyFormattingUtils.beautifyKeyId(masterKeyId));

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/operations/results/OperationResult.java

@@ -627,6 +627,8 @@ public abstract class OperationResult implements Parcelable {
         MSG_DC_ASYM (LogLevel.DEBUG, R.string.msg_dc_asym),
         MSG_DC_CHARSET (LogLevel.DEBUG, R.string.msg_dc_charset),
         MSG_DC_BACKUP_VERSION (LogLevel.DEBUG, R.string.msg_dc_backup_version),
+        MSG_DC_PASSPHRASE_FORMAT (LogLevel.DEBUG, R.string.msg_dc_passphrase_format),
+        MSG_DC_PASSPHRASE_BEGIN (LogLevel.DEBUG, R.string.msg_dc_passphrase_begin),
         MSG_DC_CLEAR_DATA (LogLevel.DEBUG, R.string.msg_dc_clear_data),
         MSG_DC_CLEAR_DECOMPRESS (LogLevel.DEBUG, R.string.msg_dc_clear_decompress),
         MSG_DC_CLEAR_META_FILE (LogLevel.DEBUG, R.string.msg_dc_clear_meta_file),

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/pgp/PgpDecryptVerifyInputParcel.java

@@ -41,6 +41,7 @@ public abstract class PgpDecryptVerifyInputParcel implements Parcelable {
 
     abstract boolean isAllowSymmetricDecryption();
     abstract boolean isDecryptMetadataOnly();
+    abstract boolean isAutocryptSetup();
 
     @Nullable
     abstract List<Long> getAllowedKeyIds();
@@ -55,7 +56,8 @@ public abstract class PgpDecryptVerifyInputParcel implements Parcelable {
     public static Builder builder() {
         return new AutoValue_PgpDecryptVerifyInputParcel.Builder()
                 .setAllowSymmetricDecryption(false)
-                .setDecryptMetadataOnly(false);
+                .setDecryptMetadataOnly(false)
+                .setAutocryptSetup(false);
     }
 
     @AutoValue.Builder
@@ -68,6 +70,7 @@ public abstract class PgpDecryptVerifyInputParcel implements Parcelable {
         public abstract Builder setDecryptMetadataOnly(boolean decryptMetadataOnly);
         public abstract Builder setDetachedSignature(byte[] detachedSignature);
         public abstract Builder setSenderAddress(String senderAddress);
+        public abstract Builder setAutocryptSetup(boolean isAutocryptSetup);
 
         public abstract Builder setAllowedKeyIds(List<Long> allowedKeyIds);
         abstract List<Long> getAllowedKeyIds();

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/pgp/PgpDecryptVerifyOperation.java

@@ -93,6 +93,7 @@ import static java.lang.String.format;
 public class PgpDecryptVerifyOperation extends BaseOperation<PgpDecryptVerifyInputParcel> {
 
     public static final int PROGRESS_STRIDE_MILLISECONDS = 200;
+    public static final String PASSPHRASE_FORMAT_NUMERIC9X4 = "numeric9x4";
 
     public PgpDecryptVerifyOperation(Context context, KeyRepository keyRepository, Progressable progressable) {
         super(context, keyRepository, progressable);
@@ -230,6 +231,8 @@ public class PgpDecryptVerifyOperation extends BaseOperation<PgpDecryptVerifyInp
     private static class ArmorHeaders {
         String charset = null;
         Integer backupVersion = null;
+        String passphraseFormat;
+        String passphraseBegin;
     }
 
     private ArmorHeaders parseArmorHeaders(InputStream in, OperationLog log, int indent) {
@@ -261,6 +264,14 @@ public class PgpDecryptVerifyOperation extends BaseOperation<PgpDecryptVerifyInp
                             }
                             break;
                         }
+                        case "passphrase-format": {
+                            armorHeaders.passphraseFormat = pieces[1].trim();
+                            break;
+                        }
+                        case "passphrase-begin": {
+                            armorHeaders.passphraseBegin = pieces[1].trim();
+                            break;
+                        }
                         default: {
                             // continue;
                         }
@@ -272,6 +283,12 @@ public class PgpDecryptVerifyOperation extends BaseOperation<PgpDecryptVerifyInp
                 if (armorHeaders.backupVersion != null) {
                     log.add(LogType.MSG_DC_BACKUP_VERSION, indent, Integer.toString(armorHeaders.backupVersion));
                 }
+                if (armorHeaders.passphraseFormat != null) {
+                    log.add(LogType.MSG_DC_PASSPHRASE_FORMAT, indent, armorHeaders.passphraseFormat);
+                }
+                if (armorHeaders.passphraseBegin != null) {
+                    log.add(LogType.MSG_DC_PASSPHRASE_BEGIN, indent, armorHeaders.passphraseBegin);
+                }
             }
         }
 
@@ -294,9 +311,16 @@ public class PgpDecryptVerifyOperation extends BaseOperation<PgpDecryptVerifyInp
         // parse ASCII Armor headers
         ArmorHeaders armorHeaders = parseArmorHeaders(in, log, indent);
         String charset = armorHeaders.charset;
-        boolean useBackupCode = false;
+        RequiredInputParcel customRequiredInputParcel = null;
         if (armorHeaders.backupVersion != null && armorHeaders.backupVersion == 2) {
-            useBackupCode = true;
+            customRequiredInputParcel = RequiredInputParcel.createRequiredBackupCode();
+        } else if (PASSPHRASE_FORMAT_NUMERIC9X4.equalsIgnoreCase(armorHeaders.passphraseFormat)) {
+            if (input.isAutocryptSetup()) {
+                customRequiredInputParcel =
+                        RequiredInputParcel.createRequiredNumeric9x4Autocrypt(armorHeaders.passphraseBegin);
+            } else {
+                customRequiredInputParcel = RequiredInputParcel.createRequiredNumeric9x4(armorHeaders.passphraseBegin);
+            }
         }
 
         OpenPgpDecryptionResultBuilder decryptionResultBuilder = new OpenPgpDecryptionResultBuilder();
@@ -311,7 +335,7 @@ public class PgpDecryptVerifyOperation extends BaseOperation<PgpDecryptVerifyInp
 
             if (obj instanceof PGPEncryptedDataList) {
                 esResult = handleEncryptedPacket(
-                        input, cryptoInput, (PGPEncryptedDataList) obj, log, indent, useBackupCode);
+                        input, cryptoInput, (PGPEncryptedDataList) obj, log, indent, customRequiredInputParcel);
 
                 // if there is an error, nothing left to do here
                 if (esResult.errorResult != null) {
@@ -565,7 +589,8 @@ public class PgpDecryptVerifyOperation extends BaseOperation<PgpDecryptVerifyInp
     }
 
     private EncryptStreamResult handleEncryptedPacket(PgpDecryptVerifyInputParcel input, CryptoInputParcel cryptoInput,
-            PGPEncryptedDataList enc, OperationLog log, int indent, boolean useBackupCode) throws PGPException {
+            PGPEncryptedDataList enc, OperationLog log, int indent, RequiredInputParcel customRequiredInputParcel)
+            throws PGPException {
 
         EncryptStreamResult result = new EncryptStreamResult();
 
@@ -723,9 +748,8 @@ public class PgpDecryptVerifyOperation extends BaseOperation<PgpDecryptVerifyInp
 
                     if (passphrase == null) {
                         log.add(LogType.MSG_DC_PENDING_PASSPHRASE, indent + 1);
-                        RequiredInputParcel requiredInputParcel = useBackupCode ?
+                        RequiredInputParcel requiredInputParcel = customRequiredInputParcel != null ?
-                                RequiredInputParcel.createRequiredBackupCode() :
+                                customRequiredInputParcel : RequiredInputParcel.createRequiredSymmetricPassphrase();
-                                RequiredInputParcel.createRequiredSymmetricPassphrase();
                         return result.with(new DecryptVerifyResult(log,
                                 requiredInputParcel,
                                 cryptoInput));
@@ -771,9 +795,8 @@ public class PgpDecryptVerifyOperation extends BaseOperation<PgpDecryptVerifyInp
                 result.cleartextStream = encryptedDataSymmetric.getDataStream(decryptorFactory);
             } catch (PGPDataValidationException e) {
                 log.add(LogType.MSG_DC_ERROR_SYM_PASSPHRASE, indent + 1);
-                RequiredInputParcel requiredInputParcel = useBackupCode ?
+                RequiredInputParcel requiredInputParcel = customRequiredInputParcel != null ?
-                        RequiredInputParcel.createRequiredBackupCode() :
+                        customRequiredInputParcel : RequiredInputParcel.createRequiredSymmetricPassphrase();
-                        RequiredInputParcel.createRequiredSymmetricPassphrase();
                 return result.with(new DecryptVerifyResult(log, requiredInputParcel, cryptoInput));
             }
 

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/pgp/PgpSignEncryptData.java

@@ -58,9 +58,13 @@ public abstract class PgpSignEncryptData implements Parcelable {
     public abstract boolean isEnableAsciiArmorOutput();
     public abstract boolean isCleartextSignature();
     public abstract boolean isDetachedSignature();
-    public abstract boolean isAddBackupHeader();
     public abstract boolean isHiddenRecipients();
 
+    @Nullable
+    public abstract String getPassphraseFormat();
+    @Nullable
+    public abstract String getPassphraseBegin();
+
     public static Builder builder() {
         return new AutoValue_PgpSignEncryptData.Builder()
                 .setSignatureMasterKeyId(Constants.key.none)
@@ -68,7 +72,6 @@ public abstract class PgpSignEncryptData implements Parcelable {
                 .setEnableAsciiArmorOutput(false)
                 .setCleartextSignature(false)
                 .setDetachedSignature(false)
-                .setAddBackupHeader(false)
                 .setHiddenRecipients(false)
                 .setCompressionAlgorithm(OpenKeychainCompressionAlgorithmTags.USE_DEFAULT)
                 .setSignatureHashAlgorithm(OpenKeychainHashAlgorithmTags.USE_DEFAULT)
@@ -91,7 +94,6 @@ public abstract class PgpSignEncryptData implements Parcelable {
         public abstract Builder setSignatureHashAlgorithm(int signatureHashAlgorithm);
         public abstract Builder setSymmetricEncryptionAlgorithm(int symmetricEncryptionAlgorithm);
 
-        public abstract Builder setAddBackupHeader(boolean isAddBackupHeader);
         public abstract Builder setEnableAsciiArmorOutput(boolean enableAsciiArmorOutput);
         public abstract Builder setCleartextSignature(boolean isCleartextSignature);
         public abstract Builder setDetachedSignature(boolean isDetachedSignature);
@@ -102,6 +104,9 @@ public abstract class PgpSignEncryptData implements Parcelable {
             setAllowedSigningKeyIds(Collections.unmodifiableList(new ArrayList<>(allowedSigningKeyIds)));
             return this;
         }
+
+        public abstract Builder setPassphraseFormat(String passphraseFormat);
+        public abstract Builder setPassphraseBegin(String passphraseBegin);
     }
 }
 

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/pgp/PgpSignEncryptOperation.java

@@ -202,9 +202,13 @@ public class PgpSignEncryptOperation extends BaseOperation<PgpSignEncryptInputPa
             if (data.getCharset() != null) {
                 armorOut.setHeader("Charset", data.getCharset());
             }
-            // add proprietary header to indicate that this is a key backup
+            String passphraseFormat = data.getPassphraseFormat();
-            if (data.isAddBackupHeader()) {
+            if (passphraseFormat != null) {
-                armorOut.setHeader("BackupVersion", "2");
+                armorOut.setHeader("Passphrase-Format", passphraseFormat);
+            }
+            String passphraseBegin = data.getPassphraseBegin();
+            if (passphraseBegin != null) {
+                armorOut.setHeader("Passphrase-Begin", passphraseBegin);
             }
             out = armorOut;
         } else {

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/remote/OpenPgpService.java

@@ -731,7 +731,7 @@ public class OpenPgpService extends Service {
             // the backup code is cached in CryptoInputParcelCacheService, now we can proceed
 
             BackupKeyringParcel input = BackupKeyringParcel
-                    .createBackupKeyringParcel(masterKeyIds, backupSecret, true, enableAsciiArmorOutput, null);
+                    .create(masterKeyIds, backupSecret, true, enableAsciiArmorOutput, null);
             BackupOperation op = new BackupOperation(this, mKeyRepository, null);
             ExportResult pgpResult = op.execute(input, inputParcel, outputStream);
 

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/service/BackupKeyringParcel.java

@@ -31,14 +31,20 @@ public abstract class BackupKeyringParcel implements Parcelable {
     @SuppressWarnings("mutable")
     public abstract long[] getMasterKeyIds();
     public abstract boolean getExportSecret();
+    public abstract boolean getExportPublic();
     public abstract boolean getIsEncrypted();
     public abstract boolean getEnableAsciiArmorOutput();
     @Nullable
     public abstract Uri getOutputUri();
 
-    public static BackupKeyringParcel createBackupKeyringParcel(long[] masterKeyIds, boolean exportSecret,
+    public static BackupKeyringParcel create(long[] masterKeyIds, boolean exportSecret,
             boolean isEncrypted, boolean enableAsciiArmorOutput, Uri outputUri) {
         return new AutoValue_BackupKeyringParcel(
-                masterKeyIds, exportSecret, isEncrypted, enableAsciiArmorOutput, outputUri);
+                masterKeyIds, exportSecret, true, isEncrypted, enableAsciiArmorOutput, outputUri);
+    }
+
+    public static BackupKeyringParcel createExportAutocryptSetupMessage(long[] masterKeyIds) {
+        return new AutoValue_BackupKeyringParcel(
+                masterKeyIds, true, false, true, true, null);
     }
 }

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/service/input/RequiredInputParcel.java

@@ -31,9 +31,17 @@ import org.sufficientlysecure.keychain.util.Passphrase;
 
 public class RequiredInputParcel implements Parcelable {
 
+    public boolean hasPassphraseBegin() {
+        return mInputData != null && mInputData.length == 1 && mInputData[0].length == 2;
+    }
+
+    public String getPassphraseBegin() {
+        return new String(mInputData[0]);
+    }
+
     public enum RequiredInputType {
         PASSPHRASE, PASSPHRASE_SYMMETRIC, PASSPHRASE_AUTH,
-        BACKUP_CODE,
+        BACKUP_CODE, NUMERIC_9X4, NUMERIC_9X4_AUTOCRYPT,
         SECURITY_TOKEN_SIGN, SECURITY_TOKEN_AUTH, SECURITY_TOKEN_DECRYPT,
         SECURITY_TOKEN_MOVE_KEY_TO_CARD, SECURITY_TOKEN_RESET_CARD,
         ENABLE_ORBOT, UPLOAD_FAIL_RETRY
@@ -179,6 +187,18 @@ public class RequiredInputParcel implements Parcelable {
                 null, null, null, (long[]) null, null);
     }
 
+    public static RequiredInputParcel createRequiredNumeric9x4(String beginChars) {
+        byte[][] inputData = beginChars != null ? new byte[][] { beginChars.getBytes() } : null;
+        return new RequiredInputParcel(RequiredInputType.NUMERIC_9X4,
+                inputData, null, null, (long[]) null, null);
+    }
+
+    public static RequiredInputParcel createRequiredNumeric9x4Autocrypt(String beginChars) {
+        byte[][] inputData = beginChars != null ? new byte[][] { beginChars.getBytes() } : null;
+        return new RequiredInputParcel(RequiredInputType.NUMERIC_9X4_AUTOCRYPT,
+                inputData, null, null, (long[]) null, null);
+    }
+
     public static RequiredInputParcel createRequiredPassphrase(
             RequiredInputParcel req) {
         return new RequiredInputParcel(RequiredInputType.PASSPHRASE,

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/BackupCodeFragment.java

@@ -20,11 +20,9 @@ package org.sufficientlysecure.keychain.ui;
 
 import java.io.File;
 import java.io.IOException;
-import java.security.SecureRandom;
 import java.text.SimpleDateFormat;
 import java.util.Date;
 import java.util.Locale;
-import java.util.Random;
 
 import android.animation.ArgbEvaluator;
 import android.animation.ValueAnimator;
@@ -52,7 +50,6 @@ import android.view.View;
 import android.view.View.OnClickListener;
 import android.view.ViewGroup;
 import android.view.animation.AccelerateInterpolator;
-import android.widget.EditText;
 import android.widget.TextView;
 
 import org.sufficientlysecure.keychain.Constants;
@@ -66,6 +63,7 @@ import org.sufficientlysecure.keychain.ui.util.Notify;
 import org.sufficientlysecure.keychain.ui.util.Notify.ActionListener;
 import org.sufficientlysecure.keychain.ui.util.Notify.Style;
 import org.sufficientlysecure.keychain.ui.widget.ToolableViewAnimator;
+import org.sufficientlysecure.keychain.util.Numeric9x4PassphraseUtil;
 import org.sufficientlysecure.keychain.util.FileHelper;
 import org.sufficientlysecure.keychain.util.Passphrase;
 
@@ -83,20 +81,13 @@ public class BackupCodeFragment extends CryptoOperationFragment<BackupKeyringPar
     public static final int REQUEST_SAVE = 1;
     public static final String ARG_BACK_STACK = "back_stack";
 
-    // https://github.com/open-keychain/open-keychain/wiki/Backups
-    // excludes 0 and O
-    private static final char[] mBackupCodeAlphabet =
-            new char[]{'1', '2', '3', '4', '5', '6', '7', '8', '9',
-                    'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N',
-                    'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z'};
-
     // argument variables
     private boolean mExportSecret;
     private long[] mMasterKeyIds;
-    String mBackupCode;
+    Passphrase mBackupCode;
     private boolean mExecuteBackupOperation;
 
-    private EditText[] mCodeEditText;
+    private TextView[] mCodeEditText;
 
     private ToolableViewAnimator mStatusAnimator, mTitleAnimator, mCodeFieldsAnimator;
     private Integer mBackStackLevel;
@@ -110,7 +101,7 @@ public class BackupCodeFragment extends CryptoOperationFragment<BackupKeyringPar
         BackupCodeFragment frag = new BackupCodeFragment();
 
         Bundle args = new Bundle();
-        args.putString(ARG_BACKUP_CODE, generateRandomBackupCode());
+        args.putParcelable(ARG_BACKUP_CODE, Numeric9x4PassphraseUtil.generateNumeric9x4Passphrase());
         args.putLongArray(ARG_MASTER_KEY_IDS, masterKeyIds);
         args.putBoolean(ARG_EXPORT_SECRET, exportSecret);
         args.putBoolean(ARG_EXECUTE_BACKUP_OPERATION, executeBackupOperation);
@@ -149,13 +140,16 @@ public class BackupCodeFragment extends CryptoOperationFragment<BackupKeyringPar
             item.setChecked(newCheckedState);
             mDebugModeAcceptAnyCode = newCheckedState;
             if (newCheckedState && TextUtils.isEmpty(mCodeEditText[0].getText())) {
-                mCodeEditText[0].setText("ABCD");
+                mCodeEditText[0].setText("1234");
-                mCodeEditText[1].setText("EFGH");
+                mCodeEditText[1].setText("5678");
-                mCodeEditText[2].setText("IJKL");
+                mCodeEditText[2].setText("9012");
-                mCodeEditText[3].setText("MNOP");
+                mCodeEditText[3].setText("3456");
-                mCodeEditText[4].setText("QRST");
+                mCodeEditText[4].setText("7890");
-                mCodeEditText[5].setText("UVWX");
+                mCodeEditText[5].setText("1234");
-                Notify.create(getActivity(), "Actual backup code is all 'A's", Style.WARN).show();
+                mCodeEditText[6].setText("5678");
+                mCodeEditText[7].setText("9012");
+                mCodeEditText[8].setText("3456");
+                Notify.create(getActivity(), "Actual backup code is all '1's", Style.WARN).show();
             }
             return true;
         }
@@ -178,7 +172,7 @@ public class BackupCodeFragment extends CryptoOperationFragment<BackupKeyringPar
                 mTitleAnimator.setDisplayedChild(1, animate);
                 mStatusAnimator.setDisplayedChild(1, animate);
                 mCodeFieldsAnimator.setDisplayedChild(1, animate);
-                for (EditText editText : mCodeEditText) {
+                for (TextView editText : mCodeEditText) {
                     editText.setText("");
                 }
 
@@ -213,7 +207,7 @@ public class BackupCodeFragment extends CryptoOperationFragment<BackupKeyringPar
 
                 hideKeyboard();
 
-                for (EditText editText : mCodeEditText) {
+                for (TextView editText : mCodeEditText) {
                     editText.setEnabled(false);
                 }
 
@@ -255,30 +249,18 @@ public class BackupCodeFragment extends CryptoOperationFragment<BackupKeyringPar
         View view = inflater.inflate(R.layout.backup_code_fragment, container, false);
 
         Bundle args = getArguments();
-        mBackupCode = args.getString(ARG_BACKUP_CODE);
+        mBackupCode = args.getParcelable(ARG_BACKUP_CODE);
         mMasterKeyIds = args.getLongArray(ARG_MASTER_KEY_IDS);
         mExportSecret = args.getBoolean(ARG_EXPORT_SECRET);
         mExecuteBackupOperation = args.getBoolean(ARG_EXECUTE_BACKUP_OPERATION, true);
 
-        mCodeEditText = new EditText[6];
+        mCodeEditText = getTransferCodeTextViews(view, R.id.transfer_code_input);
-        mCodeEditText[0] = view.findViewById(R.id.backup_code_1);
-        mCodeEditText[1] = view.findViewById(R.id.backup_code_2);
-        mCodeEditText[2] = view.findViewById(R.id.backup_code_3);
-        mCodeEditText[3] = view.findViewById(R.id.backup_code_4);
-        mCodeEditText[4] = view.findViewById(R.id.backup_code_5);
-        mCodeEditText[5] = view.findViewById(R.id.backup_code_6);
 
         {
-            TextView[] codeDisplayText = new TextView[6];
+            TextView[] codeDisplayText = getTransferCodeTextViews(view, R.id.transfer_code_display);
-            codeDisplayText[0] = view.findViewById(R.id.backup_code_display_1);
-            codeDisplayText[1] = view.findViewById(R.id.backup_code_display_2);
-            codeDisplayText[2] = view.findViewById(R.id.backup_code_display_3);
-            codeDisplayText[3] = view.findViewById(R.id.backup_code_display_4);
-            codeDisplayText[4] = view.findViewById(R.id.backup_code_display_5);
-            codeDisplayText[5] = view.findViewById(R.id.backup_code_display_6);
 
             // set backup code in code TextViews
-            char[] backupCode = mBackupCode.toCharArray();
+            char[] backupCode = mBackupCode.getCharArray();
             for (int i = 0; i < codeDisplayText.length; i++) {
                 codeDisplayText[i].setText(backupCode, i * 5, 4);
             }
@@ -340,6 +322,22 @@ public class BackupCodeFragment extends CryptoOperationFragment<BackupKeyringPar
         return view;
     }
 
+    @NonNull
+    private TextView[] getTransferCodeTextViews(View view, int transferCodeViewGroupId) {
+        ViewGroup transferCodeGroup = view.findViewById(transferCodeViewGroupId);
+        TextView[] codeDisplayText = new TextView[9];
+        codeDisplayText[0] = transferCodeGroup.findViewById(R.id.transfer_code_block_1);
+        codeDisplayText[1] = transferCodeGroup.findViewById(R.id.transfer_code_block_2);
+        codeDisplayText[2] = transferCodeGroup.findViewById(R.id.transfer_code_block_3);
+        codeDisplayText[3] = transferCodeGroup.findViewById(R.id.transfer_code_block_4);
+        codeDisplayText[4] = transferCodeGroup.findViewById(R.id.transfer_code_block_5);
+        codeDisplayText[5] = transferCodeGroup.findViewById(R.id.transfer_code_block_6);
+        codeDisplayText[6] = transferCodeGroup.findViewById(R.id.transfer_code_block_7);
+        codeDisplayText[7] = transferCodeGroup.findViewById(R.id.transfer_code_block_8);
+        codeDisplayText[8] = transferCodeGroup.findViewById(R.id.transfer_code_block_9);
+        return codeDisplayText;
+    }
+
     private void showFaq() {
         HelpActivity.startHelpActivity(getActivity(), HelpActivity.TAB_FAQ);
     }
@@ -369,8 +367,8 @@ public class BackupCodeFragment extends CryptoOperationFragment<BackupKeyringPar
         outState.putInt(ARG_BACK_STACK, mBackStackLevel == null ? -1 : mBackStackLevel);
     }
 
-    private void setupEditTextSuccessListener(final EditText[] backupCodes) {
+    private void setupEditTextSuccessListener(final TextView[] backupCodes) {
-        for (EditText backupCode : backupCodes) {
+        for (TextView backupCode : backupCodes) {
 
             backupCode.addTextChangedListener(new TextWatcher() {
                 @Override
@@ -410,7 +408,7 @@ public class BackupCodeFragment extends CryptoOperationFragment<BackupKeyringPar
         }
 
         StringBuilder backupCodeInput = new StringBuilder(26);
-        for (EditText editText : mCodeEditText) {
+        for (TextView editText : mCodeEditText) {
             if (editText.getText().length() < 4) {
                 return;
             }
@@ -449,7 +447,7 @@ public class BackupCodeFragment extends CryptoOperationFragment<BackupKeyringPar
 
     }
 
-    private static void setupEditTextFocusNext(final EditText[] backupCodes) {
+    private static void setupEditTextFocusNext(final TextView[] backupCodes) {
         for (int i = 0; i < backupCodes.length - 1; i++) {
 
             final int next = i + 1;
@@ -516,9 +514,9 @@ public class BackupCodeFragment extends CryptoOperationFragment<BackupKeyringPar
                 + (mExportSecret ? Constants.FILE_EXTENSION_ENCRYPTED_BACKUP_SECRET
                 : Constants.FILE_EXTENSION_ENCRYPTED_BACKUP_PUBLIC);
 
-        Passphrase passphrase = new Passphrase(mBackupCode);
+        Passphrase passphrase = new Passphrase(mBackupCode.getCharArray());
         if (Constants.DEBUG && mDebugModeAcceptAnyCode) {
-            passphrase = new Passphrase("AAAA-AAAA-AAAA-AAAA-AAAA-AAAA");
+            passphrase = new Passphrase("1111-1111-1111-1111-1111-1111-1111-1111-1111");
         }
 
         // if we don't want to execute the actual operation outside of this activity, drop out here
@@ -612,7 +610,7 @@ public class BackupCodeFragment extends CryptoOperationFragment<BackupKeyringPar
     @Override
     public BackupKeyringParcel createOperationInput() {
         return BackupKeyringParcel
-                .createBackupKeyringParcel(mMasterKeyIds, mExportSecret, true, true, mCachedBackupUri);
+                .create(mMasterKeyIds, mExportSecret, true, true, mCachedBackupUri);
     }
 
     @Override
@@ -631,27 +629,4 @@ public class BackupCodeFragment extends CryptoOperationFragment<BackupKeyringPar
         mCachedBackupUri = null;
     }
 
-    /**
-     * Generate backup code using format defined in
-     * https://github.com/open-keychain/open-keychain/wiki/Backups
-     */
-    @NonNull
-    private static String generateRandomBackupCode() {
-
-        Random r = new SecureRandom();
-
-        // simple generation of a 24 character backup code
-        StringBuilder code = new StringBuilder(28);
-        for (int i = 0; i < 24; i++) {
-            if (i == 4 || i == 8 || i == 12 || i == 16 || i == 20) {
-                code.append('-');
-            }
-
-            code.append(mBackupCodeAlphabet[r.nextInt(mBackupCodeAlphabet.length)]);
-        }
-
-        return code.toString();
-    }
-
-
 }

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/DecryptActivity.java

@@ -42,6 +42,7 @@ import org.sufficientlysecure.keychain.ui.base.BaseActivity;
 
 
 public class DecryptActivity extends BaseActivity {
+    public static final String APPLICATION_AUTOCRYPT_SETUP = "application/autocrypt-setup";
 
     /* Intents */
     public static final String ACTION_DECRYPT_FROM_CLIPBOARD = "DECRYPT_DATA_CLIPBOARD";
@@ -84,6 +85,7 @@ public class DecryptActivity extends BaseActivity {
 
         // depending on the data source, we may or may not be able to delete the original file
         boolean canDelete = false;
+        boolean isAutocryptSetup = false;
 
         try {
 
@@ -160,6 +162,9 @@ public class DecryptActivity extends BaseActivity {
                 case Constants.DECRYPT_DATA:
                 default:
                     Uri uri = intent.getData();
+
+                    isAutocryptSetup = APPLICATION_AUTOCRYPT_SETUP.equalsIgnoreCase(intent.getType());
+
                     if (uri != null) {
 
                         if ("com.android.email.attachmentprovider".equals(uri.getHost())) {
@@ -187,7 +192,7 @@ public class DecryptActivity extends BaseActivity {
             return;
         }
 
-        displayListFragment(uris, canDelete);
+        displayListFragment(uris, canDelete, isAutocryptSetup);
 
     }
 
@@ -211,9 +216,9 @@ public class DecryptActivity extends BaseActivity {
         return tempFile;
     }
 
-    public void displayListFragment(ArrayList<Uri> inputUris, boolean canDelete) {
+    public void displayListFragment(ArrayList<Uri> inputUris, boolean canDelete, boolean isAutocryptSetup) {
 
-        DecryptListFragment frag = DecryptListFragment.newInstance(inputUris, canDelete);
+        DecryptListFragment frag = DecryptListFragment.newInstance(inputUris, canDelete, isAutocryptSetup);
 
         FragmentManager fragMan = getSupportFragmentManager();
 

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/DecryptListFragment.java

@@ -125,6 +125,7 @@ public class DecryptListFragment
     public static final String ARG_CANCELLED_URIS = "cancelled_uris";
     public static final String ARG_RESULTS = "results";
     public static final String ARG_CAN_DELETE = "can_delete";
+    public static final String ARG_IS_AUTOCRYPT_SETUP = "is_autocrypt_setup";
 
     private static final int REQUEST_CODE_OUTPUT = 0x00007007;
     private static final int REQUEST_PERMISSION_READ_EXTERNAL_STORAGE = 12;
@@ -136,6 +137,7 @@ public class DecryptListFragment
 
     private Uri mCurrentInputUri;
     private boolean mCanDelete;
+    private boolean mIsAutocryptSetup;
 
     private DecryptFilesAdapter mAdapter;
     private Uri mCurrentSaveFileUri;
@@ -143,12 +145,13 @@ public class DecryptListFragment
     /**
      * Creates new instance of this fragment
      */
-    public static DecryptListFragment newInstance(@NonNull ArrayList<Uri> uris, boolean canDelete) {
+    public static DecryptListFragment newInstance(@NonNull ArrayList<Uri> uris, boolean canDelete, boolean isAutocryptSetup) {
         DecryptListFragment frag = new DecryptListFragment();
 
         Bundle args = new Bundle();
         args.putParcelableArrayList(ARG_INPUT_URIS, uris);
         args.putBoolean(ARG_CAN_DELETE, canDelete);
+        args.putBoolean(ARG_IS_AUTOCRYPT_SETUP, isAutocryptSetup);
         frag.setArguments(args);
 
         return frag;
@@ -205,6 +208,7 @@ public class DecryptListFragment
         outState.putParcelable(ARG_OUTPUT_URIS, new ParcelableHashMap<>(mInputDataResults));
         outState.putParcelableArrayList(ARG_CANCELLED_URIS, mCancelledInputUris);
         outState.putBoolean(ARG_CAN_DELETE, mCanDelete);
+        outState.putBoolean(ARG_IS_AUTOCRYPT_SETUP, mIsAutocryptSetup);
 
         // this does not save mCurrentInputUri - if anything is being
         // processed at fragment recreation time, the operation in
@@ -222,6 +226,7 @@ public class DecryptListFragment
         ParcelableHashMap<Uri, InputDataResult> results = args.getParcelable(ARG_RESULTS);
 
         mCanDelete = args.getBoolean(ARG_CAN_DELETE, false);
+        mIsAutocryptSetup = args.getBoolean(ARG_IS_AUTOCRYPT_SETUP, false);
 
         displayInputUris(inputUris, cancelledUris,
                 results != null ? results.getMap() : null
@@ -638,11 +643,14 @@ public class DecryptListFragment
         }
 
         PgpDecryptVerifyInputParcel.Builder decryptInput = PgpDecryptVerifyInputParcel.builder()
-                .setAllowSymmetricDecryption(true);
+                .setAllowSymmetricDecryption(true)
+                .setAutocryptSetup(mIsAutocryptSetup);
         return InputDataParcel.createInputDataParcel(mCurrentInputUri, decryptInput.build());
 
     }
 
+
+
     /**
      * Request READ_EXTERNAL_STORAGE permission on Android >= 6.0 to read content from "file" Uris.
      * <p/>

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/PassphraseDialogActivity.java

@@ -31,6 +31,7 @@ import android.support.v4.app.DialogFragment;
 import android.support.v4.app.FragmentActivity;
 import android.support.v7.app.AlertDialog;
 import android.text.Editable;
+import android.text.InputFilter;
 import android.text.InputType;
 import android.text.TextWatcher;
 import android.text.method.PasswordTransformationMethod;
@@ -68,6 +69,7 @@ import org.sufficientlysecure.keychain.service.input.RequiredInputParcel.Require
 import org.sufficientlysecure.keychain.ui.dialog.CustomAlertDialogBuilder;
 import org.sufficientlysecure.keychain.ui.util.ThemeChanger;
 import org.sufficientlysecure.keychain.ui.widget.CacheTTLSpinner;
+import org.sufficientlysecure.keychain.ui.widget.PrefixedEditText;
 import org.sufficientlysecure.keychain.util.Passphrase;
 import org.sufficientlysecure.keychain.util.Preferences;
 import timber.log.Timber;
@@ -193,7 +195,7 @@ public class PassphraseDialogActivity extends FragmentActivity {
                 mBackupCodeEditText[4] = view.findViewById(R.id.backup_code_5);
                 mBackupCodeEditText[5] = view.findViewById(R.id.backup_code_6);
 
-                setupEditTextFocusNext(mBackupCodeEditText);
+                setupEditTextFocusNext(mBackupCodeEditText, false);
 
                 AlertDialog dialog = alert.create();
                 dialog.setButton(DialogInterface.BUTTON_POSITIVE,
@@ -201,6 +203,49 @@ public class PassphraseDialogActivity extends FragmentActivity {
                 return dialog;
             }
 
+            if (mRequiredInput.mType == RequiredInputType.NUMERIC_9X4 ||
+                    mRequiredInput.mType == RequiredInputType.NUMERIC_9X4_AUTOCRYPT) {
+                LayoutInflater inflater = LayoutInflater.from(theme);
+                View view = inflater.inflate(R.layout.passphrase_dialog_numeric_9x4, null);
+                alert.setView(view);
+
+                mBackupCodeEditText = new EditText[9];
+                mBackupCodeEditText[0] = view.findViewById(R.id.transfer_code_block_1);
+                mBackupCodeEditText[1] = view.findViewById(R.id.transfer_code_block_2);
+                mBackupCodeEditText[2] = view.findViewById(R.id.transfer_code_block_3);
+                mBackupCodeEditText[3] = view.findViewById(R.id.transfer_code_block_4);
+                mBackupCodeEditText[4] = view.findViewById(R.id.transfer_code_block_5);
+                mBackupCodeEditText[5] = view.findViewById(R.id.transfer_code_block_6);
+                mBackupCodeEditText[6] = view.findViewById(R.id.transfer_code_block_7);
+                mBackupCodeEditText[7] = view.findViewById(R.id.transfer_code_block_8);
+                mBackupCodeEditText[8] = view.findViewById(R.id.transfer_code_block_9);
+
+                if (mRequiredInput.hasPassphraseBegin()) {
+                    String beginChars = mRequiredInput.getPassphraseBegin();
+                    int inputLength = 4 - beginChars.length();
+                    setupEditTextFocusNext(mBackupCodeEditText, true);
+
+                    PrefixedEditText prefixEditText = (PrefixedEditText) mBackupCodeEditText[0];
+                    if (beginChars.matches("\\d\\d")) {
+                        prefixEditText.setPrefix(beginChars);
+                        prefixEditText.setHint("1234".substring(inputLength));
+                        prefixEditText.setFilters(new InputFilter[] { new InputFilter.LengthFilter(inputLength) });
+                    }
+                } else {
+                    setupEditTextFocusNext(mBackupCodeEditText, false);
+                }
+
+                if (mRequiredInput.mType == RequiredInputType.NUMERIC_9X4_AUTOCRYPT) {
+                    TextView promptText = view.findViewById(R.id.passphrase_text);
+                    promptText.setText(R.string.passphrase_transfer_autocrypt);
+                }
+
+                AlertDialog dialog = alert.create();
+                dialog.setButton(DialogInterface.BUTTON_POSITIVE,
+                        activity.getString(R.string.btn_proceed), (DialogInterface.OnClickListener) null);
+                return dialog;
+            }
+
             LayoutInflater inflater = LayoutInflater.from(theme);
             mLayout = (ViewAnimator) inflater.inflate(R.layout.passphrase_dialog, null);
             alert.setView(mLayout);
@@ -377,10 +422,9 @@ public class PassphraseDialogActivity extends FragmentActivity {
             textView.requestFocus();
         }
 
-        private static void setupEditTextFocusNext(final EditText[] backupCodes) {
+        private static void setupEditTextFocusNext(EditText[] backupCodes, boolean hasPrefix) {
             for (int i = 0; i < backupCodes.length - 1; i++) {
-
+                int idx = i;
-                final int next = i + 1;
 
                 backupCodes[i].addTextChangedListener(new TextWatcher() {
                     @Override
@@ -390,10 +434,11 @@ public class PassphraseDialogActivity extends FragmentActivity {
                     @Override
                     public void onTextChanged(CharSequence s, int start, int before, int count) {
                         boolean inserting = before < count;
-                        boolean cursorAtEnd = (start + count) == 4;
+                        int maxLen = hasPrefix && idx == 0 ? 2 : 4;
+                        boolean cursorAtEnd = (start + count) == maxLen;
 
                         if (inserting && cursorAtEnd) {
-                            backupCodes[next].requestFocus();
+                            backupCodes[idx + 1].requestFocus();
                         }
                     }
 
@@ -401,7 +446,6 @@ public class PassphraseDialogActivity extends FragmentActivity {
                     public void afterTextChanged(Editable s) {
                     }
                 });
-
             }
         }
 
@@ -432,6 +476,27 @@ public class PassphraseDialogActivity extends FragmentActivity {
                         return;
                     }
 
+                    if (mRequiredInput.mType == RequiredInputType.NUMERIC_9X4 ||
+                            mRequiredInput.mType == RequiredInputType.NUMERIC_9X4_AUTOCRYPT) {
+                        StringBuilder backupCodeInput = new StringBuilder(36);
+                        if (mRequiredInput.hasPassphraseBegin()) {
+                            backupCodeInput.append(mRequiredInput.getPassphraseBegin());
+                        }
+                        for (EditText editText : mBackupCodeEditText) {
+                            if (editText.getText().length() != 2 && editText.getText().length() != 4) {
+                                return;
+                            }
+                            backupCodeInput.append(editText.getText());
+                            backupCodeInput.append('-');
+                        }
+                        backupCodeInput.deleteCharAt(backupCodeInput.length() - 1);
+
+                        Passphrase passphrase = new Passphrase(backupCodeInput.toString());
+                        finishCaching(passphrase, null);
+
+                        return;
+                    }
+
                     final Passphrase passphrase = new Passphrase(mPassphraseEditText);
                     final int timeToLiveSeconds = mTimeToLiveSpinner.getSelectedTimeToLive();
 

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/base/CryptoOperationHelper.java

@@ -162,7 +162,9 @@ public class CryptoOperationHelper<T extends Parcelable, S extends OperationResu
 
             case PASSPHRASE:
             case PASSPHRASE_SYMMETRIC:
-            case BACKUP_CODE: {
+            case BACKUP_CODE:
+            case NUMERIC_9X4:
+            case NUMERIC_9X4_AUTOCRYPT: {
                 Intent intent = new Intent(activity, PassphraseDialogActivity.class);
                 intent.putExtra(PassphraseDialogActivity.EXTRA_REQUIRED_INPUT, requiredInput);
                 intent.putExtra(PassphraseDialogActivity.EXTRA_CRYPTO_INPUT, cryptoInputParcel);

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/widget/PrefixedEditText.java

@@ -21,21 +21,25 @@ import android.content.Context;
 import android.content.res.TypedArray;
 import android.graphics.*;
 import android.support.annotation.NonNull;
+import android.support.v7.widget.AppCompatEditText;
+import android.text.Layout;
+import android.text.TextPaint;
 import android.util.AttributeSet;
-import android.widget.EditText;
 
 import org.sufficientlysecure.keychain.R;
 
-public class PrefixedEditText extends EditText {
+public class PrefixedEditText extends AppCompatEditText {
 
-    private String mPrefix;
+    private CharSequence mPrefix;
-    private Rect mPrefixRect = new Rect();
+    private int mPrefixColor;
+    private int desiredWidth;
 
-	public PrefixedEditText(Context context, AttributeSet attrs) {
+    public PrefixedEditText(Context context, AttributeSet attrs) {
 		super(context, attrs);
         TypedArray style = context.getTheme().obtainStyledAttributes(
                 attrs, R.styleable.PrefixedEditText, 0, 0);
         mPrefix = style.getString(R.styleable.PrefixedEditText_prefix);
+        mPrefixColor = style.getColor(R.styleable.PrefixedEditText_prefixColor, getCurrentTextColor());
         if (mPrefix == null) {
             mPrefix = "";
         }
@@ -43,20 +47,29 @@ public class PrefixedEditText extends EditText {
 
     @Override
     protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
-        getPaint().getTextBounds(mPrefix, 0, mPrefix.length(), mPrefixRect);
-
         super.onMeasure(widthMeasureSpec, heightMeasureSpec);
+        desiredWidth = (int) Math.ceil(Layout.getDesiredWidth(mPrefix, getPaint()));
     }
 
     @Override
     protected void onDraw(@NonNull Canvas canvas) {
         super.onDraw(canvas);
-        canvas.drawText(mPrefix, super.getCompoundPaddingLeft(), getBaseline(), getPaint());
+        TextPaint paint = getPaint();
+        // reset to the actual text color - it might be the hint color currently
+        paint.setColor(mPrefixColor);
+        canvas.drawText(mPrefix, 0, mPrefix.length(), super.getCompoundPaddingLeft(), getBaseline(), paint);
     }
 
     @Override
     public int getCompoundPaddingLeft() {
-        return super.getCompoundPaddingLeft() + mPrefixRect.width();
+        return super.getCompoundPaddingLeft() + desiredWidth;
+    }
+
+    public void setPrefix(CharSequence prefix) {
+	    mPrefix = prefix;
+
+	    invalidate();
+	    requestLayout();
     }
 
 }

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/util/Numeric9x4PassphraseUtil.java

@@ -0,0 +1,59 @@
+/*
+ * Copyright (C) 2017 Schürmann & Breitmoser GbR
+ *
+ * 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.util;
+
+
+import java.nio.CharBuffer;
+import java.security.SecureRandom;
+import java.util.Random;
+import java.util.regex.Pattern;
+
+import android.support.annotation.VisibleForTesting;
+
+// see https://autocrypt.org/level1.html#setup-code
+public class Numeric9x4PassphraseUtil {
+    public static Passphrase generateNumeric9x4Passphrase() {
+        return generateNumeric9x4Passphrase(new SecureRandom());
+    }
+
+    @VisibleForTesting
+    static Passphrase generateNumeric9x4Passphrase(Random r) {
+        StringBuilder code = new StringBuilder(36);
+        for (int i = 0; i < 36; i++) {
+            boolean isBeginningOfBlock = i > 0 && (i % 4) == 0;
+            if (isBeginningOfBlock) {
+                code.append('-');
+            }
+
+            String digit = Integer.toString(r.nextInt(10));
+            code.append(digit);
+        }
+
+        return new Passphrase(code.toString());
+    }
+
+    private static final Pattern AUTOCRYPT_TRANSFER_CODE = Pattern.compile("(\\d{4}-){8}\\d{4}");
+
+    public static boolean isNumeric9x4Passphrase(Passphrase transferCodeChars) {
+        return isNumeric9x4Passphrase(CharBuffer.wrap(transferCodeChars.getCharArray()));
+    }
+
+    public static boolean isNumeric9x4Passphrase(CharSequence code) {
+        return AUTOCRYPT_TRANSFER_CODE.matcher(code).matches();
+    }
+}

OpenKeychain/src/main/res/layout-w400dp/backup_code_fragment.xml

@@ -1,459 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
-    xmlns:custom="http://schemas.android.com/apk/res-auto"
-    xmlns:tools="http://schemas.android.com/tools"
-    android:layout_width="match_parent"
-    android:layout_height="match_parent"
-    android:orientation="vertical"
-    android:paddingTop="20dp">
-
-    <org.sufficientlysecure.keychain.ui.widget.ToolableViewAnimator
-        android:id="@+id/title_animator"
-        android:layout_width="match_parent"
-        android:layout_height="wrap_content"
-        android:layout_gravity="center_horizontal"
-        android:inAnimation="@anim/fade_in"
-        android:outAnimation="@anim/fade_out"
-        custom:initialView="0">
-
-        <TextView
-            style="?android:textAppearanceMedium"
-            android:layout_width="wrap_content"
-            android:layout_height="wrap_content"
-            android:layout_gravity="center_horizontal"
-            android:gravity="center_horizontal"
-            android:padding="10dp"
-            android:text="@string/backup_code_explanation" />
-
-        <TextView
-            style="?android:textAppearanceMedium"
-            android:layout_width="wrap_content"
-            android:layout_height="wrap_content"
-            android:layout_gravity="center_horizontal"
-            android:gravity="center_horizontal"
-            android:padding="10dp"
-            android:text="@string/backup_code_enter" />
-
-        <TextView
-            style="?android:textAppearanceMedium"
-            android:layout_width="wrap_content"
-            android:layout_height="wrap_content"
-            android:layout_gravity="center_horizontal"
-            android:gravity="center_horizontal"
-            android:padding="10dp"
-            android:text="@string/backup_code_ok" />
-
-    </org.sufficientlysecure.keychain.ui.widget.ToolableViewAnimator>
-
-    <org.sufficientlysecure.keychain.ui.widget.ToolableViewAnimator
-        android:id="@+id/code_animator"
-        android:layout_width="match_parent"
-        android:layout_height="wrap_content"
-        android:layout_gravity="center_horizontal"
-        android:layout_marginBottom="15dp"
-        android:layout_marginTop="15dp"
-        android:inAnimation="@anim/fade_in"
-        android:outAnimation="@anim/fade_out"
-        custom:initialView="1">
-
-        <LinearLayout
-            android:layout_width="wrap_content"
-            android:layout_height="wrap_content"
-            android:layout_gravity="center_horizontal">
-
-            <TextView
-                android:id="@+id/backup_code_display_1"
-                style="@android:style/Widget.EditText"
-                android:layout_width="wrap_content"
-                android:layout_height="wrap_content"
-                android:layout_gravity="center_horizontal"
-                android:clickable="false"
-                android:focusable="false"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="SpUsage"
-                tools:text="ABCD" />
-
-            <TextView
-                android:layout_width="wrap_content"
-                android:layout_height="match_parent"
-                android:gravity="center_vertical"
-                android:text="-"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="HardcodedText,SpUsage" />
-
-            <TextView
-                android:id="@+id/backup_code_display_2"
-                style="@android:style/Widget.EditText"
-                android:layout_width="wrap_content"
-                android:layout_height="wrap_content"
-                android:layout_gravity="center_horizontal"
-                android:clickable="false"
-                android:focusable="false"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="SpUsage"
-                tools:text="EFGH" />
-
-            <TextView
-                android:layout_width="wrap_content"
-                android:layout_height="match_parent"
-                android:gravity="center_vertical"
-                android:text="-"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="HardcodedText,SpUsage" />
-
-            <TextView
-                android:id="@+id/backup_code_display_3"
-                style="@android:style/Widget.EditText"
-                android:layout_width="wrap_content"
-                android:layout_height="wrap_content"
-                android:layout_gravity="center_horizontal"
-                android:clickable="false"
-                android:focusable="false"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="SpUsage"
-                tools:text="IJKL" />
-
-            <TextView
-                android:layout_width="wrap_content"
-                android:layout_height="match_parent"
-                android:gravity="center_vertical"
-                android:text="-"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="HardcodedText,SpUsage" />
-
-            <TextView
-                android:id="@+id/backup_code_display_4"
-                style="@android:style/Widget.EditText"
-                android:layout_width="wrap_content"
-                android:layout_height="wrap_content"
-                android:layout_gravity="center_horizontal"
-                android:clickable="false"
-                android:focusable="false"
-                android:singleLine="true"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="SpUsage"
-                tools:text="MNOP" />
-
-            <TextView
-                android:layout_width="wrap_content"
-                android:layout_height="match_parent"
-                android:gravity="center_vertical"
-                android:text="-"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="HardcodedText,SpUsage" />
-
-            <TextView
-                android:id="@+id/backup_code_display_5"
-                style="@android:style/Widget.EditText"
-                android:layout_width="wrap_content"
-                android:layout_height="wrap_content"
-                android:layout_gravity="center_horizontal"
-                android:clickable="false"
-                android:focusable="false"
-                android:singleLine="true"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="SpUsage"
-                tools:text="QRST" />
-
-            <TextView
-                android:layout_width="wrap_content"
-                android:layout_height="match_parent"
-                android:gravity="center_vertical"
-                android:text="-"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="HardcodedText,SpUsage" />
-
-            <TextView
-                android:id="@+id/backup_code_display_6"
-                style="@android:style/Widget.EditText"
-                android:layout_width="wrap_content"
-                android:layout_height="wrap_content"
-                android:layout_gravity="center_horizontal"
-                android:clickable="false"
-                android:focusable="false"
-                android:singleLine="true"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="SpUsage"
-                tools:text="UVWX" />
-
-        </LinearLayout>
-
-        <LinearLayout
-            android:layout_width="wrap_content"
-            android:layout_height="wrap_content"
-            android:layout_gravity="center_horizontal">
-
-            <!--
-            The most reliable way to correctly size these I found was to put a transparent hint on them.
-             Theoretically, this should be what the android:ems attribute is for - didn't work for me.
-            -->
-            <EditText
-                android:id="@+id/backup_code_1"
-                android:layout_width="wrap_content"
-                android:layout_height="wrap_content"
-                android:layout_gravity="center_horizontal"
-                android:hint="ABCD"
-                android:inputType="textNoSuggestions|textCapCharacters"
-                android:maxLength="4"
-                android:singleLine="true"
-                android:textColorHint="@android:color/transparent"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="HardcodedText,SpUsage" />
-
-            <TextView
-                android:layout_width="wrap_content"
-                android:layout_height="match_parent"
-                android:gravity="center_vertical"
-                android:text="-"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="HardcodedText,SpUsage" />
-
-            <EditText
-                android:id="@+id/backup_code_2"
-                android:layout_width="wrap_content"
-                android:layout_height="wrap_content"
-                android:layout_gravity="center_horizontal"
-                android:hint="ABCD"
-                android:inputType="textNoSuggestions|textCapCharacters"
-                android:maxLength="4"
-                android:singleLine="true"
-                android:textColorHint="@android:color/transparent"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="HardcodedText,SpUsage" />
-
-            <TextView
-                android:layout_width="wrap_content"
-                android:layout_height="match_parent"
-                android:gravity="center_vertical"
-                android:text="-"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="HardcodedText,SpUsage" />
-
-            <EditText
-                android:id="@+id/backup_code_3"
-                android:layout_width="wrap_content"
-                android:layout_height="wrap_content"
-                android:layout_gravity="center_horizontal"
-                android:hint="ABCD"
-                android:inputType="textNoSuggestions|textCapCharacters"
-                android:maxLength="4"
-                android:singleLine="true"
-                android:textColorHint="@android:color/transparent"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="HardcodedText,SpUsage" />
-
-            <TextView
-                android:layout_width="wrap_content"
-                android:layout_height="match_parent"
-                android:gravity="center_vertical"
-                android:text="-"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="HardcodedText,SpUsage" />
-
-            <EditText
-                android:id="@+id/backup_code_4"
-                android:layout_width="wrap_content"
-                android:layout_height="wrap_content"
-                android:layout_gravity="center_horizontal"
-                android:hint="ABCD"
-                android:inputType="textNoSuggestions|textCapCharacters"
-                android:maxLength="4"
-                android:singleLine="true"
-                android:textColorHint="@android:color/transparent"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="HardcodedText,SpUsage" />
-
-            <TextView
-                android:layout_width="wrap_content"
-                android:layout_height="match_parent"
-                android:gravity="center_vertical"
-                android:text="-"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="HardcodedText,SpUsage" />
-
-            <EditText
-                android:id="@+id/backup_code_5"
-                android:layout_width="wrap_content"
-                android:layout_height="wrap_content"
-                android:layout_gravity="center_horizontal"
-                android:hint="ABCD"
-                android:inputType="textNoSuggestions|textCapCharacters"
-                android:maxLength="4"
-                android:singleLine="true"
-                android:textColorHint="@android:color/transparent"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="HardcodedText,SpUsage" />
-
-            <TextView
-                android:layout_width="wrap_content"
-                android:layout_height="match_parent"
-                android:gravity="center_vertical"
-                android:text="-"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="HardcodedText,SpUsage" />
-
-            <EditText
-                android:id="@+id/backup_code_6"
-                android:layout_width="wrap_content"
-                android:layout_height="wrap_content"
-                android:layout_gravity="center_horizontal"
-                android:hint="ABCD"
-                android:inputType="textNoSuggestions|textCapCharacters"
-                android:maxLength="4"
-                android:singleLine="true"
-                android:textColorHint="@android:color/transparent"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="HardcodedText,SpUsage" />
-
-        </LinearLayout>
-
-    </org.sufficientlysecure.keychain.ui.widget.ToolableViewAnimator>
-
-    <org.sufficientlysecure.keychain.ui.widget.ToolableViewAnimator
-        android:id="@+id/button_bar_animator"
-        android:layout_width="match_parent"
-        android:layout_height="wrap_content"
-        android:layout_gravity="center_horizontal"
-        android:inAnimation="@anim/fade_in_delayed"
-        android:outAnimation="@anim/fade_out"
-        custom:initialView="2">
-
-        <Button
-            android:id="@+id/button_backup_input"
-            style="?android:buttonBarButtonStyle"
-            android:layout_width="wrap_content"
-            android:layout_height="wrap_content"
-            android:layout_gravity="center_horizontal"
-            android:layout_margin="10dp"
-            android:drawableLeft="@drawable/ic_mode_edit_grey_24dp"
-            android:drawablePadding="8dp"
-            android:padding="12dp"
-            android:text="@string/btn_code_wrotedown" />
-
-        <Space
-            android:layout_width="wrap_content"
-            android:layout_height="wrap_content" />
-
-        <LinearLayout
-            android:layout_width="wrap_content"
-            android:layout_height="wrap_content"
-            android:layout_gravity="center_horizontal"
-            android:orientation="vertical">
-
-            <TextView
-                style="?android:textAppearanceMedium"
-                android:layout_width="wrap_content"
-                android:layout_height="wrap_content"
-                android:gravity="center_horizontal"
-                android:text="@string/backup_code_wrong" />
-
-            <Button
-                android:id="@+id/button_backup_back"
-                style="?android:buttonBarButtonStyle"
-                android:layout_width="wrap_content"
-                android:layout_height="wrap_content"
-                android:layout_gravity="center_horizontal"
-                android:layout_margin="10dp"
-                android:drawableLeft="@drawable/ic_repeat_grey_24dp"
-                android:drawablePadding="8dp"
-                android:padding="12dp"
-                android:text="@string/btn_backup_back" />
-
-        </LinearLayout>
-
-        <LinearLayout
-            style="?android:buttonBarStyle"
-            android:layout_width="wrap_content"
-            android:layout_height="wrap_content"
-            android:layout_gravity="center_horizontal"
-            android:orientation="vertical">
-
-            <LinearLayout
-                style="?android:buttonBarStyle"
-                android:layout_width="wrap_content"
-                android:layout_height="wrap_content"
-                android:layout_gravity="center_horizontal">
-
-                <Button
-                    android:id="@+id/button_backup_share"
-                    style="?android:buttonBarButtonStyle"
-                    android:layout_width="0dp"
-                    android:layout_height="wrap_content"
-                    android:layout_margin="10dp"
-                    android:layout_weight="1"
-                    android:drawableLeft="@drawable/ic_share_grey_24dp"
-                    android:drawablePadding="8dp"
-                    android:padding="12dp"
-                    android:text="@string/btn_backup_share" />
-
-                <Button
-                    android:id="@+id/button_backup_save"
-                    style="?android:buttonBarButtonStyle"
-                    android:layout_width="0dp"
-                    android:layout_height="wrap_content"
-                    android:layout_margin="10dp"
-                    android:layout_weight="1"
-                    android:drawableLeft="@drawable/ic_save_grey_24dp"
-                    android:drawablePadding="8dp"
-                    android:padding="12dp"
-                    android:text="@string/btn_backup_save" />
-
-
-            </LinearLayout>
-
-            <Button
-                android:id="@+id/button_faq"
-                style="?android:buttonBarButtonStyle"
-                android:layout_width="match_parent"
-                android:layout_height="wrap_content"
-                android:gravity="center"
-                android:text="@string/how_to_import" />
-        </LinearLayout>
-
-    </org.sufficientlysecure.keychain.ui.widget.ToolableViewAnimator>
-
-</LinearLayout>

OpenKeychain/src/main/res/layout-w600dp/backup_code_fragment.xml

@@ -1,459 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
-    xmlns:custom="http://schemas.android.com/apk/res-auto"
-    xmlns:tools="http://schemas.android.com/tools"
-    android:layout_width="match_parent"
-    android:layout_height="match_parent"
-    android:orientation="vertical"
-    android:paddingTop="20dp">
-
-    <org.sufficientlysecure.keychain.ui.widget.ToolableViewAnimator
-        android:id="@+id/title_animator"
-        android:layout_width="match_parent"
-        android:layout_height="wrap_content"
-        android:layout_gravity="center_horizontal"
-        android:inAnimation="@anim/fade_in"
-        android:outAnimation="@anim/fade_out"
-        custom:initialView="0">
-
-        <TextView
-            style="?android:textAppearanceMedium"
-            android:layout_width="wrap_content"
-            android:layout_height="wrap_content"
-            android:layout_gravity="center_horizontal"
-            android:gravity="center_horizontal"
-            android:padding="10dp"
-            android:text="@string/backup_code_explanation" />
-
-        <TextView
-            style="?android:textAppearanceMedium"
-            android:layout_width="wrap_content"
-            android:layout_height="wrap_content"
-            android:layout_gravity="center_horizontal"
-            android:gravity="center_horizontal"
-            android:padding="10dp"
-            android:text="@string/backup_code_enter" />
-
-        <TextView
-            style="?android:textAppearanceMedium"
-            android:layout_width="wrap_content"
-            android:layout_height="wrap_content"
-            android:layout_gravity="center_horizontal"
-            android:gravity="center_horizontal"
-            android:padding="10dp"
-            android:text="@string/backup_code_ok" />
-
-    </org.sufficientlysecure.keychain.ui.widget.ToolableViewAnimator>
-
-    <org.sufficientlysecure.keychain.ui.widget.ToolableViewAnimator
-        android:id="@+id/code_animator"
-        android:layout_width="match_parent"
-        android:layout_height="wrap_content"
-        android:layout_gravity="center_horizontal"
-        android:layout_marginBottom="15dp"
-        android:layout_marginTop="15dp"
-        android:inAnimation="@anim/fade_in"
-        android:outAnimation="@anim/fade_out"
-        custom:initialView="1">
-
-        <LinearLayout
-            android:layout_width="wrap_content"
-            android:layout_height="wrap_content"
-            android:layout_gravity="center_horizontal">
-
-            <TextView
-                android:id="@+id/backup_code_display_1"
-                style="@android:style/Widget.EditText"
-                android:layout_width="wrap_content"
-                android:layout_height="wrap_content"
-                android:layout_gravity="center_horizontal"
-                android:clickable="false"
-                android:focusable="false"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="SpUsage"
-                tools:text="ABCD" />
-
-            <TextView
-                android:layout_width="wrap_content"
-                android:layout_height="match_parent"
-                android:gravity="center_vertical"
-                android:text="-"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="HardcodedText,SpUsage" />
-
-            <TextView
-                android:id="@+id/backup_code_display_2"
-                style="@android:style/Widget.EditText"
-                android:layout_width="wrap_content"
-                android:layout_height="wrap_content"
-                android:layout_gravity="center_horizontal"
-                android:clickable="false"
-                android:focusable="false"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="SpUsage"
-                tools:text="EFGH" />
-
-            <TextView
-                android:layout_width="wrap_content"
-                android:layout_height="match_parent"
-                android:gravity="center_vertical"
-                android:text="-"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="HardcodedText,SpUsage" />
-
-            <TextView
-                android:id="@+id/backup_code_display_3"
-                style="@android:style/Widget.EditText"
-                android:layout_width="wrap_content"
-                android:layout_height="wrap_content"
-                android:layout_gravity="center_horizontal"
-                android:clickable="false"
-                android:focusable="false"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="SpUsage"
-                tools:text="IJKL" />
-
-            <TextView
-                android:layout_width="wrap_content"
-                android:layout_height="match_parent"
-                android:gravity="center_vertical"
-                android:text="-"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="HardcodedText,SpUsage" />
-
-            <TextView
-                android:id="@+id/backup_code_display_4"
-                style="@android:style/Widget.EditText"
-                android:layout_width="wrap_content"
-                android:layout_height="wrap_content"
-                android:layout_gravity="center_horizontal"
-                android:clickable="false"
-                android:focusable="false"
-                android:singleLine="true"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="SpUsage"
-                tools:text="MNOP" />
-
-            <TextView
-                android:layout_width="wrap_content"
-                android:layout_height="match_parent"
-                android:gravity="center_vertical"
-                android:text="-"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="HardcodedText,SpUsage" />
-
-            <TextView
-                android:id="@+id/backup_code_display_5"
-                style="@android:style/Widget.EditText"
-                android:layout_width="wrap_content"
-                android:layout_height="wrap_content"
-                android:layout_gravity="center_horizontal"
-                android:clickable="false"
-                android:focusable="false"
-                android:singleLine="true"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="SpUsage"
-                tools:text="QRST" />
-
-            <TextView
-                android:layout_width="wrap_content"
-                android:layout_height="match_parent"
-                android:gravity="center_vertical"
-                android:text="-"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="HardcodedText,SpUsage" />
-
-            <TextView
-                android:id="@+id/backup_code_display_6"
-                style="@android:style/Widget.EditText"
-                android:layout_width="wrap_content"
-                android:layout_height="wrap_content"
-                android:layout_gravity="center_horizontal"
-                android:clickable="false"
-                android:focusable="false"
-                android:singleLine="true"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="SpUsage"
-                tools:text="UVWX" />
-
-        </LinearLayout>
-
-        <LinearLayout
-            android:layout_width="wrap_content"
-            android:layout_height="wrap_content"
-            android:layout_gravity="center_horizontal">
-
-            <!--
-            The most reliable way to correctly size these I found was to put a transparent hint on them.
-             Theoretically, this should be what the android:ems attribute is for - didn't work for me.
-            -->
-            <EditText
-                android:id="@+id/backup_code_1"
-                android:layout_width="wrap_content"
-                android:layout_height="wrap_content"
-                android:layout_gravity="center_horizontal"
-                android:hint="ABCD"
-                android:inputType="textNoSuggestions|textCapCharacters"
-                android:maxLength="4"
-                android:singleLine="true"
-                android:textColorHint="@android:color/transparent"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="HardcodedText,SpUsage" />
-
-            <TextView
-                android:layout_width="wrap_content"
-                android:layout_height="match_parent"
-                android:gravity="center_vertical"
-                android:text="-"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="HardcodedText,SpUsage" />
-
-            <EditText
-                android:id="@+id/backup_code_2"
-                android:layout_width="wrap_content"
-                android:layout_height="wrap_content"
-                android:layout_gravity="center_horizontal"
-                android:hint="ABCD"
-                android:inputType="textNoSuggestions|textCapCharacters"
-                android:maxLength="4"
-                android:singleLine="true"
-                android:textColorHint="@android:color/transparent"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="HardcodedText,SpUsage" />
-
-            <TextView
-                android:layout_width="wrap_content"
-                android:layout_height="match_parent"
-                android:gravity="center_vertical"
-                android:text="-"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="HardcodedText,SpUsage" />
-
-            <EditText
-                android:id="@+id/backup_code_3"
-                android:layout_width="wrap_content"
-                android:layout_height="wrap_content"
-                android:layout_gravity="center_horizontal"
-                android:hint="ABCD"
-                android:inputType="textNoSuggestions|textCapCharacters"
-                android:maxLength="4"
-                android:singleLine="true"
-                android:textColorHint="@android:color/transparent"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="HardcodedText,SpUsage" />
-
-            <TextView
-                android:layout_width="wrap_content"
-                android:layout_height="match_parent"
-                android:gravity="center_vertical"
-                android:text="-"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="HardcodedText,SpUsage" />
-
-            <EditText
-                android:id="@+id/backup_code_4"
-                android:layout_width="wrap_content"
-                android:layout_height="wrap_content"
-                android:layout_gravity="center_horizontal"
-                android:hint="ABCD"
-                android:inputType="textNoSuggestions|textCapCharacters"
-                android:maxLength="4"
-                android:singleLine="true"
-                android:textColorHint="@android:color/transparent"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="HardcodedText,SpUsage" />
-
-            <TextView
-                android:layout_width="wrap_content"
-                android:layout_height="match_parent"
-                android:gravity="center_vertical"
-                android:text="-"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="HardcodedText,SpUsage" />
-
-            <EditText
-                android:id="@+id/backup_code_5"
-                android:layout_width="wrap_content"
-                android:layout_height="wrap_content"
-                android:layout_gravity="center_horizontal"
-                android:hint="ABCD"
-                android:inputType="textNoSuggestions|textCapCharacters"
-                android:maxLength="4"
-                android:singleLine="true"
-                android:textColorHint="@android:color/transparent"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="HardcodedText,SpUsage" />
-
-            <TextView
-                android:layout_width="wrap_content"
-                android:layout_height="match_parent"
-                android:gravity="center_vertical"
-                android:text="-"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="HardcodedText,SpUsage" />
-
-            <EditText
-                android:id="@+id/backup_code_6"
-                android:layout_width="wrap_content"
-                android:layout_height="wrap_content"
-                android:layout_gravity="center_horizontal"
-                android:hint="ABCD"
-                android:inputType="textNoSuggestions|textCapCharacters"
-                android:maxLength="4"
-                android:singleLine="true"
-                android:textColorHint="@android:color/transparent"
-                android:textSize="18dp"
-                android:textStyle="bold"
-                android:typeface="monospace"
-                tools:ignore="HardcodedText,SpUsage" />
-
-        </LinearLayout>
-
-    </org.sufficientlysecure.keychain.ui.widget.ToolableViewAnimator>
-
-    <org.sufficientlysecure.keychain.ui.widget.ToolableViewAnimator
-        android:id="@+id/button_bar_animator"
-        android:layout_width="match_parent"
-        android:layout_height="wrap_content"
-        android:layout_gravity="center_horizontal"
-        android:inAnimation="@anim/fade_in_delayed"
-        android:outAnimation="@anim/fade_out"
-        custom:initialView="2">
-
-        <Button
-            android:id="@+id/button_backup_input"
-            style="?android:buttonBarButtonStyle"
-            android:layout_width="wrap_content"
-            android:layout_height="wrap_content"
-            android:layout_gravity="center_horizontal"
-            android:layout_margin="10dp"
-            android:drawableLeft="@drawable/ic_mode_edit_grey_24dp"
-            android:drawablePadding="8dp"
-            android:padding="12dp"
-            android:text="@string/btn_code_wrotedown" />
-
-        <Space
-            android:layout_width="wrap_content"
-            android:layout_height="wrap_content" />
-
-        <LinearLayout
-            android:layout_width="wrap_content"
-            android:layout_height="wrap_content"
-            android:layout_gravity="center_horizontal"
-            android:orientation="horizontal">
-
-            <TextView
-                style="?android:textAppearanceMedium"
-                android:layout_width="wrap_content"
-                android:layout_height="wrap_content"
-                android:gravity="center_horizontal"
-                android:text="@string/backup_code_wrong" />
-
-            <Button
-                android:id="@+id/button_backup_back"
-                style="?android:buttonBarButtonStyle"
-                android:layout_width="wrap_content"
-                android:layout_height="wrap_content"
-                android:layout_gravity="center_horizontal"
-                android:layout_margin="10dp"
-                android:drawableLeft="@drawable/ic_repeat_grey_24dp"
-                android:drawablePadding="8dp"
-                android:padding="12dp"
-                android:text="@string/btn_backup_back" />
-
-        </LinearLayout>
-
-        <LinearLayout
-            style="?android:buttonBarStyle"
-            android:layout_width="wrap_content"
-            android:layout_height="wrap_content"
-            android:layout_gravity="center_horizontal"
-            android:orientation="vertical">
-
-            <LinearLayout
-                style="?android:buttonBarStyle"
-                android:layout_width="wrap_content"
-                android:layout_height="wrap_content"
-                android:layout_gravity="center_horizontal">
-
-                <Button
-                    android:id="@+id/button_backup_share"
-                    style="?android:buttonBarButtonStyle"
-                    android:layout_width="0dp"
-                    android:layout_height="wrap_content"
-                    android:layout_margin="10dp"
-                    android:layout_weight="1"
-                    android:drawableLeft="@drawable/ic_share_grey_24dp"
-                    android:drawablePadding="8dp"
-                    android:padding="12dp"
-                    android:text="@string/btn_backup_share" />
-
-                <Button
-                    android:id="@+id/button_backup_save"
-                    style="?android:buttonBarButtonStyle"
-                    android:layout_width="0dp"
-                    android:layout_height="wrap_content"
-                    android:layout_margin="10dp"
-                    android:layout_weight="1"
-                    android:drawableLeft="@drawable/ic_save_grey_24dp"
-                    android:drawablePadding="8dp"
-                    android:padding="12dp"
-                    android:text="@string/btn_backup_save" />
-
-
-            </LinearLayout>
-
-            <Button
-                android:id="@+id/button_faq"
-                style="?android:buttonBarButtonStyle"
-                android:layout_width="match_parent"
-                android:layout_height="wrap_content"
-                android:gravity="center"
-                android:text="@string/how_to_import" />
-        </LinearLayout>
-
-    </org.sufficientlysecure.keychain.ui.widget.ToolableViewAnimator>
-
-</LinearLayout>

OpenKeychain/src/main/res/layout/backup_code_fragment.xml

@@ -56,330 +56,9 @@
         android:outAnimation="@anim/fade_out"
         custom:initialView="1">
 
-        <LinearLayout
+        <include layout="@layout/transfer_code_display" android:id="@+id/transfer_code_display" />
-            android:layout_width="wrap_content"
-            android:layout_height="wrap_content"
-            android:layout_gravity="center_horizontal"
-            android:orientation="vertical">
 
-            <LinearLayout
+        <include layout="@layout/transfer_code_input" android:id="@+id/transfer_code_input" />
-                android:layout_width="wrap_content"
-                android:layout_height="wrap_content"
-                android:layout_gravity="right"
-                android:orientation="horizontal">
-
-                <TextView
-                    android:id="@+id/backup_code_display_1"
-                    style="@android:style/Widget.EditText"
-                    android:layout_width="wrap_content"
-                    android:layout_height="wrap_content"
-                    android:layout_gravity="center_horizontal"
-                    android:clickable="false"
-                    android:focusable="false"
-                    android:textSize="18dp"
-                    android:textStyle="bold"
-                    android:typeface="monospace"
-                    tools:ignore="SpUsage"
-                    tools:text="ABCD" />
-
-                <TextView
-                    android:layout_width="wrap_content"
-                    android:layout_height="match_parent"
-                    android:gravity="center_vertical"
-                    android:text="-"
-                    android:textSize="18dp"
-                    android:textStyle="bold"
-                    android:typeface="monospace"
-                    tools:ignore="HardcodedText,SpUsage" />
-
-                <TextView
-                    android:id="@+id/backup_code_display_2"
-                    style="@android:style/Widget.EditText"
-                    android:layout_width="wrap_content"
-                    android:layout_height="wrap_content"
-                    android:layout_gravity="center_horizontal"
-                    android:clickable="false"
-                    android:focusable="false"
-                    android:textSize="18dp"
-                    android:textStyle="bold"
-                    android:typeface="monospace"
-                    tools:ignore="SpUsage"
-                    tools:text="EFGH" />
-
-                <TextView
-                    android:layout_width="wrap_content"
-                    android:layout_height="match_parent"
-                    android:gravity="center_vertical"
-                    android:text="-"
-                    android:textSize="18dp"
-                    android:textStyle="bold"
-                    android:typeface="monospace"
-                    tools:ignore="HardcodedText,SpUsage" />
-
-                <TextView
-                    android:id="@+id/backup_code_display_3"
-                    style="@android:style/Widget.EditText"
-                    android:layout_width="wrap_content"
-                    android:layout_height="wrap_content"
-                    android:layout_gravity="center_horizontal"
-                    android:clickable="false"
-                    android:focusable="false"
-                    android:textSize="18dp"
-                    android:textStyle="bold"
-                    android:typeface="monospace"
-                    tools:ignore="SpUsage"
-                    tools:text="IJKL" />
-
-            </LinearLayout>
-
-            <LinearLayout
-                android:layout_width="wrap_content"
-                android:layout_height="wrap_content"
-                android:orientation="horizontal">
-
-                <TextView
-                    android:layout_width="wrap_content"
-                    android:layout_height="match_parent"
-                    android:gravity="center_vertical"
-                    android:text="-"
-                    android:textSize="18dp"
-                    android:textStyle="bold"
-                    android:typeface="monospace"
-                    tools:ignore="HardcodedText,SpUsage" />
-
-                <TextView
-                    android:id="@+id/backup_code_display_4"
-                    style="@android:style/Widget.EditText"
-                    android:layout_width="wrap_content"
-                    android:layout_height="wrap_content"
-                    android:layout_gravity="center_horizontal"
-                    android:clickable="false"
-                    android:focusable="false"
-                    android:singleLine="true"
-                    android:textSize="18dp"
-                    android:textStyle="bold"
-                    android:typeface="monospace"
-                    tools:ignore="SpUsage"
-                    tools:text="MNOP" />
-
-                <TextView
-                    android:layout_width="wrap_content"
-                    android:layout_height="match_parent"
-                    android:gravity="center_vertical"
-                    android:text="-"
-                    android:textSize="18dp"
-                    android:textStyle="bold"
-                    android:typeface="monospace"
-                    tools:ignore="HardcodedText,SpUsage" />
-
-                <TextView
-                    android:id="@+id/backup_code_display_5"
-                    style="@android:style/Widget.EditText"
-                    android:layout_width="wrap_content"
-                    android:layout_height="wrap_content"
-                    android:layout_gravity="center_horizontal"
-                    android:clickable="false"
-                    android:focusable="false"
-                    android:singleLine="true"
-                    android:textSize="18dp"
-                    android:textStyle="bold"
-                    android:typeface="monospace"
-                    tools:ignore="SpUsage"
-                    tools:text="QRST" />
-
-                <TextView
-                    android:layout_width="wrap_content"
-                    android:layout_height="match_parent"
-                    android:gravity="center_vertical"
-                    android:text="-"
-                    android:textSize="18dp"
-                    android:textStyle="bold"
-                    android:typeface="monospace"
-                    tools:ignore="HardcodedText,SpUsage" />
-
-                <TextView
-                    android:id="@+id/backup_code_display_6"
-                    style="@android:style/Widget.EditText"
-                    android:layout_width="wrap_content"
-                    android:layout_height="wrap_content"
-                    android:layout_gravity="center_horizontal"
-                    android:clickable="false"
-                    android:focusable="false"
-                    android:singleLine="true"
-                    android:textSize="18dp"
-                    android:textStyle="bold"
-                    android:typeface="monospace"
-                    tools:ignore="SpUsage"
-                    tools:text="UVWX" />
-            </LinearLayout>
-        </LinearLayout>
-
-        <LinearLayout
-            android:layout_width="wrap_content"
-            android:layout_height="wrap_content"
-            android:layout_gravity="center_horizontal"
-            android:orientation="vertical">
-
-            <LinearLayout
-                android:layout_width="wrap_content"
-                android:layout_height="wrap_content"
-                android:layout_gravity="right"
-                android:orientation="horizontal">
-
-                <!--
-                The most reliable way to correctly size these I found was to put a transparent hint on them.
-                 Theoretically, this should be what the android:ems attribute is for - didn't work for me.
-                -->
-                <EditText
-                    android:id="@+id/backup_code_1"
-                    android:layout_width="wrap_content"
-                    android:layout_height="wrap_content"
-                    android:layout_gravity="center_horizontal"
-                    android:hint="ABCD"
-                    android:inputType="textNoSuggestions|textCapCharacters"
-                    android:maxLength="4"
-                    android:singleLine="true"
-                    android:textColorHint="@android:color/transparent"
-                    android:textSize="18dp"
-                    android:textStyle="bold"
-                    android:typeface="monospace"
-                    tools:ignore="HardcodedText,SpUsage" />
-
-                <TextView
-                    android:layout_width="wrap_content"
-                    android:layout_height="match_parent"
-                    android:gravity="center_vertical"
-                    android:text="-"
-                    android:textSize="18dp"
-                    android:textStyle="bold"
-                    android:typeface="monospace"
-                    tools:ignore="HardcodedText,SpUsage" />
-
-                <EditText
-                    android:id="@+id/backup_code_2"
-                    android:layout_width="wrap_content"
-                    android:layout_height="wrap_content"
-                    android:layout_gravity="center_horizontal"
-                    android:hint="ABCD"
-                    android:inputType="textNoSuggestions|textCapCharacters"
-                    android:maxLength="6"
-                    android:singleLine="true"
-                    android:textColorHint="@android:color/transparent"
-                    android:textSize="18dp"
-                    android:textStyle="bold"
-                    android:typeface="monospace"
-                    tools:ignore="HardcodedText,SpUsage" />
-
-                <TextView
-                    android:layout_width="wrap_content"
-                    android:layout_height="match_parent"
-                    android:gravity="center_vertical"
-                    android:text="-"
-                    android:textSize="18dp"
-                    android:textStyle="bold"
-                    android:typeface="monospace"
-                    tools:ignore="HardcodedText,SpUsage" />
-
-                <EditText
-                    android:id="@+id/backup_code_3"
-                    android:layout_width="wrap_content"
-                    android:layout_height="wrap_content"
-                    android:layout_gravity="center_horizontal"
-                    android:hint="ABCD"
-                    android:inputType="textNoSuggestions|textCapCharacters"
-                    android:maxLength="6"
-                    android:singleLine="true"
-                    android:textColorHint="@android:color/transparent"
-                    android:textSize="18dp"
-                    android:textStyle="bold"
-                    android:typeface="monospace"
-                    tools:ignore="HardcodedText,SpUsage" />
-
-
-            </LinearLayout>
-
-            <LinearLayout
-                android:layout_width="wrap_content"
-                android:layout_height="wrap_content"
-                android:orientation="horizontal">
-
-                <TextView
-                    android:layout_width="wrap_content"
-                    android:layout_height="match_parent"
-                    android:gravity="center_vertical"
-                    android:text="-"
-                    android:textSize="18dp"
-                    android:textStyle="bold"
-                    android:typeface="monospace"
-                    tools:ignore="HardcodedText,SpUsage" />
-
-                <EditText
-                    android:id="@+id/backup_code_4"
-                    android:layout_width="wrap_content"
-                    android:layout_height="wrap_content"
-                    android:layout_gravity="center_horizontal"
-                    android:hint="ABCD"
-                    android:inputType="textNoSuggestions|textCapCharacters"
-                    android:maxLength="6"
-                    android:singleLine="true"
-                    android:textColorHint="@android:color/transparent"
-                    android:textSize="18dp"
-                    android:textStyle="bold"
-                    android:typeface="monospace"
-                    tools:ignore="HardcodedText,SpUsage" />
-
-                <TextView
-                    android:layout_width="wrap_content"
-                    android:layout_height="match_parent"
-                    android:gravity="center_vertical"
-                    android:text="-"
-                    android:textSize="18dp"
-                    android:textStyle="bold"
-                    android:typeface="monospace"
-                    tools:ignore="HardcodedText,SpUsage" />
-
-                <EditText
-                    android:id="@+id/backup_code_5"
-                    android:layout_width="wrap_content"
-                    android:layout_height="wrap_content"
-                    android:layout_gravity="center_horizontal"
-                    android:hint="ABCD"
-                    android:inputType="textNoSuggestions|textCapCharacters"
-                    android:maxLength="6"
-                    android:singleLine="true"
-                    android:textColorHint="@android:color/transparent"
-                    android:textSize="18dp"
-                    android:textStyle="bold"
-                    android:typeface="monospace"
-                    tools:ignore="HardcodedText,SpUsage" />
-
-                <TextView
-                    android:layout_width="wrap_content"
-                    android:layout_height="match_parent"
-                    android:gravity="center_vertical"
-                    android:text="-"
-                    android:textSize="18dp"
-                    android:textStyle="bold"
-                    android:typeface="monospace"
-                    tools:ignore="HardcodedText,SpUsage" />
-
-                <EditText
-                    android:id="@+id/backup_code_6"
-                    android:layout_width="wrap_content"
-                    android:layout_height="wrap_content"
-                    android:layout_gravity="center_horizontal"
-                    android:hint="ABCD"
-                    android:inputType="textNoSuggestions|textCapCharacters"
-                    android:maxLength="6"
-                    android:singleLine="true"
-                    android:textColorHint="@android:color/transparent"
-                    android:textSize="18dp"
-                    android:textStyle="bold"
-                    android:typeface="monospace"
-                    tools:ignore="HardcodedText,SpUsage" />
-
-            </LinearLayout>
-        </LinearLayout>
 
     </org.sufficientlysecure.keychain.ui.widget.ToolableViewAnimator>
 

OpenKeychain/src/main/res/layout/passphrase_dialog_numeric_9x4.xml

@@ -0,0 +1,54 @@
+<?xml version="1.0" encoding="utf-8"?>
+<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="match_parent"
+    android:layout_height="wrap_content"
+    android:orientation="vertical"
+    android:paddingBottom="14dp"
+    android:paddingTop="14dp">
+
+    <LinearLayout
+        android:id="@+id/input"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:orientation="vertical">
+
+        <TextView
+            android:id="@+id/passphrase_text"
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:layout_marginLeft="24dp"
+            android:layout_marginRight="24dp"
+            android:layout_marginBottom="24dp"
+            android:text="@string/passphrase_transfer"
+            android:textAppearance="@style/TextAppearance.AppCompat.Medium" />
+
+        <include layout="@layout/transfer_code_input" />
+
+    </LinearLayout>
+
+    <LinearLayout
+        android:id="@+id/progress"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_centerInParent="true"
+        android:orientation="horizontal"
+        android:visibility="invisible">
+
+        <ProgressBar
+            style="?android:attr/progressBarStyle"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_gravity="center_horizontal" />
+
+        <TextView
+            style="?android:attr/textAppearanceMedium"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_gravity="center_vertical"
+            android:padding="4dp"
+            android:text="@string/label_unlock" />
+
+    </LinearLayout>
+
+</RelativeLayout>

OpenKeychain/src/main/res/layout/transfer_code_display.xml

@@ -0,0 +1,145 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="wrap_content"
+    android:layout_height="wrap_content"
+    xmlns:custom="http://schemas.android.com/apk/res-auto"
+    android:layout_gravity="center_horizontal"
+    android:orientation="vertical">
+
+    <LinearLayout
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:orientation="horizontal">
+
+        <!--
+            The most reliable way to correctly size these I found was to put a transparent hint on them.
+             Theoretically, this should be what the android:ems attribute is for - didn't work for me.
+            -->
+        <org.sufficientlysecure.keychain.ui.widget.PrefixedEditText
+            android:id="@+id/transfer_code_block_1"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:background="@android:color/transparent"
+            android:enabled="false"
+            custom:prefixColor="@color/md_grey_600"
+            tools:hint="34"
+            tools:prefix="12"
+            tools:text="34"
+            style="@style/TransferCodeText"
+            />
+
+        <TextView
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            style="@style/TransferCodeTextSep" />
+
+        <TextView
+            android:id="@+id/transfer_code_block_2"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            style="@style/TransferCodeText"
+            tools:text="1234" />
+
+        <TextView
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            style="@style/TransferCodeTextSep" />
+
+        <TextView
+            android:id="@+id/transfer_code_block_3"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            style="@style/TransferCodeText"
+            tools:text="1234" />
+
+        <TextView
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            style="@style/TransferCodeTextSep" />
+
+    </LinearLayout>
+
+    <LinearLayout
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:orientation="horizontal">
+
+        <TextView
+            android:id="@+id/transfer_code_block_4"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            style="@style/TransferCodeText"
+            tools:text="1234" />
+
+        <TextView
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            style="@style/TransferCodeTextSep" />
+
+        <TextView
+            android:id="@+id/transfer_code_block_5"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            style="@style/TransferCodeText"
+            tools:text="1234" />
+
+        <TextView
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            style="@style/TransferCodeTextSep" />
+
+        <TextView
+            android:id="@+id/transfer_code_block_6"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            style="@style/TransferCodeText"
+            tools:text="1234" />
+
+        <TextView
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            style="@style/TransferCodeTextSep" />
+
+    </LinearLayout>
+
+    <LinearLayout
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:orientation="horizontal">
+
+        <TextView
+            android:id="@+id/transfer_code_block_7"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            style="@style/TransferCodeText"
+            tools:text="1234" />
+
+        <TextView
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            style="@style/TransferCodeTextSep" />
+
+        <TextView
+            android:id="@+id/transfer_code_block_8"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            style="@style/TransferCodeText"
+            tools:text="1234" />
+
+        <TextView
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            style="@style/TransferCodeTextSep" />
+
+        <TextView
+            android:id="@+id/transfer_code_block_9"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            style="@style/TransferCodeText"
+            tools:text="1234" />
+
+    </LinearLayout>
+
+</LinearLayout>

OpenKeychain/src/main/res/layout/transfer_code_input.xml

@@ -0,0 +1,138 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="wrap_content"
+    android:layout_height="wrap_content"
+    xmlns:custom="http://schemas.android.com/apk/res-auto"
+    android:layout_gravity="center_horizontal"
+    android:orientation="vertical"
+    tools:showIn="@layout/backup_code_fragment">
+
+    <LinearLayout
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:orientation="horizontal">
+
+        <org.sufficientlysecure.keychain.ui.widget.PrefixedEditText
+            android:id="@+id/transfer_code_block_1"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            custom:prefixColor="@color/md_grey_600"
+            tools:prefix="12"
+            tools:hint="34"
+            style="@style/TransferCodeText"
+            />
+
+        <TextView
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            style="@style/TransferCodeTextSep" />
+
+        <EditText
+            android:id="@+id/transfer_code_block_2"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            style="@style/TransferCodeText" />
+
+        <TextView
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            style="@style/TransferCodeTextSep" />
+
+        <EditText
+            android:id="@+id/transfer_code_block_3"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            style="@style/TransferCodeText"
+            />
+
+        <TextView
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            style="@style/TransferCodeTextSep" />
+
+    </LinearLayout>
+
+    <LinearLayout
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:orientation="horizontal">
+
+        <EditText
+            android:id="@+id/transfer_code_block_4"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            style="@style/TransferCodeText"
+            />
+
+        <TextView
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            style="@style/TransferCodeTextSep" />
+
+        <EditText
+            android:id="@+id/transfer_code_block_5"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            style="@style/TransferCodeText"
+            />
+
+        <TextView
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            style="@style/TransferCodeTextSep" />
+
+        <EditText
+            android:id="@+id/transfer_code_block_6"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            style="@style/TransferCodeText"
+            />
+
+        <TextView
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            style="@style/TransferCodeTextSep" />
+
+    </LinearLayout>
+
+    <LinearLayout
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:orientation="horizontal">
+
+        <EditText
+            android:id="@+id/transfer_code_block_7"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            style="@style/TransferCodeText"
+            />
+
+        <TextView
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            style="@style/TransferCodeTextSep" />
+
+        <EditText
+            android:id="@+id/transfer_code_block_8"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            style="@style/TransferCodeText"
+            />
+
+        <TextView
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            style="@style/TransferCodeTextSep" />
+
+        <EditText
+            android:id="@+id/transfer_code_block_9"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            style="@style/TransferCodeText"
+            />
+
+    </LinearLayout>
+
+</LinearLayout>

OpenKeychain/src/main/res/values/attr.xml

@@ -13,6 +13,7 @@
 
     <declare-styleable name="PrefixedEditText">
         <attr name="prefix" format="string" />
+        <attr name="prefixColor" format="color" />
     </declare-styleable>
 
 </resources>

OpenKeychain/src/main/res/values/strings.xml

@@ -102,6 +102,7 @@
     <string name="btn_encrypt_text">"Encrypt text"</string>
     <string name="btn_add_email">"Add additional email address"</string>
     <string name="btn_unlock">"Unlock"</string>
+    <string name="btn_proceed">"Proceed"</string>
     <string name="btn_add_keyserver">"Add"</string>
     <string name="btn_save_default">"Save as default"</string>
     <string name="btn_saved">"Saved!"</string>
@@ -333,6 +334,8 @@
     <string name="passphrase_for_any">"Enter password"</string>
     <string name="passphrase_keyboard_hint_alpha">"Switch to alphabetic keyboard"</string>
     <string name="passphrase_keyboard_hint_numeric">"Switch to numeric keyboard"</string>
+    <string name="passphrase_transfer">"Enter transfer code"</string>
+    <string name="passphrase_transfer_autocrypt">"To import this Autocrypt Setup Message, enter transfer code:"</string>
     <string name="pin_for">"Enter PIN for '%s'"</string>
     <string name="security_token_pin_for">"Enter PIN to access Security Token for '%s'"</string>
     <string name="security_token_nfc_text">"Hold Security Token against the NFC marker at the back of your device."</string>
@@ -633,6 +636,7 @@
     <string name="intent_import_key">"Import Key with OpenKeychain"</string>
     <string name="intent_send_encrypt">"Encrypt with OpenKeychain"</string>
     <string name="intent_send_decrypt">"Decrypt with OpenKeychain"</string>
+    <string name="intent_autocrypt_setup">"Import Autocrypt Setup Message"</string>
 
     <!-- Remote API -->
     <string name="api_settings_show_info">"Show advanced information"</string>
@@ -1176,6 +1180,8 @@
     <string name="msg_dc_asym">"Found block of asymmetrically encrypted data for key %s"</string>
     <string name="msg_dc_charset">"Found charset header: '%s'"</string>
     <string name="msg_dc_backup_version">"Found backupVersion header: '%s'"</string>
+    <string name="msg_dc_passphrase_format">"Found Passphrase-Format header: '%s'"</string>
+    <string name="msg_dc_passphrase_begin">"Found Passphrase-Begin header: '%s'"</string>
     <string name="msg_dc_clear_data">"Processing literal data"</string>
     <string name="msg_dc_clear_decompress">"Unpacking compressed data"</string>
     <string name="msg_dc_clear_meta_file">"Filename: %s"</string>

OpenKeychain/src/main/res/values/styles.xml

@@ -65,4 +65,23 @@
         <item name="android:textSize" tools:ignore="SpUsage">14dp</item>
     </style>
 
+    <style name="TransferCodeText">
+        <item name="android:gravity">center_vertical</item>
+        <item name="android:singleLine">true</item>
+        <item name="android:hint">1234</item>
+        <item name="android:maxLength">4</item>
+        <item name="android:textColorHint">@android:color/transparent</item>
+        <item name="android:textSize">18sp</item>
+        <item name="android:minHeight">42sp</item>
+        <item name="android:textStyle">bold</item>
+        <item name="android:typeface">monospace</item>
+        <item name="android:textColor">#000</item>
+        <item name="android:inputType">numberPassword|textVisiblePassword</item>
+    </style>
+
+    <style name="TransferCodeTextSep" parent="TransferCodeText">
+        <item name="android:hint"></item>
+        <item name="android:text">-</item>
+    </style>
+
 </resources>

OpenKeychain/src/test/java/org/sufficientlysecure/keychain/operations/BackupOperationTest.java

@@ -157,7 +157,7 @@ public class BackupOperationTest {
         assertTrue("second keyring has local certification", checkForLocal(mStaticRing2));
 
         ByteArrayOutputStream out = new ByteArrayOutputStream();
-        boolean result = op.exportKeysToStream(new OperationLog(), null, false, out);
+        boolean result = op.exportKeysToStream(new OperationLog(), null, false, true, out);
 
         assertTrue("export must be a success", result);
 
@@ -194,7 +194,7 @@ public class BackupOperationTest {
         }
 
         out = new ByteArrayOutputStream();
-        result = op.exportKeysToStream(new OperationLog(), null, true, out);
+        result = op.exportKeysToStream(new OperationLog(), null, true, true, out);
 
         assertTrue("export must be a success", result);
 
@@ -252,7 +252,7 @@ public class BackupOperationTest {
         BackupOperation op = new BackupOperation(spyApplication,
                 KeyWritableRepository.create(RuntimeEnvironment.application), null);
 
-        BackupKeyringParcel parcel = BackupKeyringParcel.createBackupKeyringParcel(
+        BackupKeyringParcel parcel = BackupKeyringParcel.create(
                 new long[] { mStaticRing1.getMasterKeyId() }, false, false, true, fakeOutputUri);
 
         ExportResult result = op.execute(parcel, null);
@@ -309,7 +309,7 @@ public class BackupOperationTest {
             BackupOperation op = new BackupOperation(spyApplication,
                     KeyWritableRepository.create(RuntimeEnvironment.application), null);
 
-            BackupKeyringParcel parcel = BackupKeyringParcel.createBackupKeyringParcel(
+            BackupKeyringParcel parcel = BackupKeyringParcel.create(
                     new long[] { mStaticRing1.getMasterKeyId() }, false, true, true, fakeOutputUri);
             CryptoInputParcel inputParcel = CryptoInputParcel.createCryptoInputParcel(passphrase);
             ExportResult result = op.execute(parcel, inputParcel);

OpenKeychain/src/test/java/org/sufficientlysecure/keychain/util/Numeric9x4PassphraseUtilTest.java

@@ -0,0 +1,40 @@
+package org.sufficientlysecure.keychain.util;
+
+
+import java.util.Random;
+
+import org.junit.Test;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+
+
+public class Numeric9x4PassphraseUtilTest {
+    private static final int RANDOM_SEED = 12345;
+    private static final String TRANSFER_CODE_3x3x4 = "1018-5452-1972-0624-7325-1126-8153-1997-1535";
+
+    @Test
+    public void generateNumeric9x4Passphrase() {
+        Random r = new Random(RANDOM_SEED);
+
+        Passphrase passphrase = Numeric9x4PassphraseUtil.generateNumeric9x4Passphrase(r);
+
+        assertEquals(TRANSFER_CODE_3x3x4, passphrase.toStringUnsafe());
+    }
+
+    @Test
+    public void isNumeric9x4Passphrase() {
+        boolean isValidCodeLayout = Numeric9x4PassphraseUtil.isNumeric9x4Passphrase(TRANSFER_CODE_3x3x4);
+
+        assertTrue(isValidCodeLayout);
+    }
+
+
+    @Test
+    public void isNumeric9x4Passphrase_withBadSuffix() {
+        boolean isValidCodeLayout = Numeric9x4PassphraseUtil.isNumeric9x4Passphrase(TRANSFER_CODE_3x3x4 + "x");
+
+        assertFalse(isValidCodeLayout);
+    }
+}