Support backupVersion ASCII Armor header

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/Constants.java

@@ -82,7 +82,6 @@ public final class Constants {
 
     public static final class Path {
         public static final File APP_DIR = new File(Environment.getExternalStorageDirectory(), "OpenKeychain");
-        public static final File APP_DIR_FILE = new File(APP_DIR, "export.asc");
     }
 
     public static final class Notification {

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

@@ -142,6 +142,7 @@ public class BackupOperation extends BaseOperation<BackupKeyringParcel> {
             PgpSignEncryptInputParcel inputParcel = new PgpSignEncryptInputParcel();
             inputParcel.setSymmetricPassphrase(exportInput.mSymmetricPassphrase);
             inputParcel.setEnableAsciiArmorOutput(true);
+            inputParcel.setAddBackupHeader(true);
 
             InputStream inStream = mContext.getContentResolver().openInputStream(exportOutputUri);
 

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

@@ -639,6 +639,7 @@ public abstract class OperationResult implements Parcelable {
         MSG_DC_ASKIP_NOT_ALLOWED (LogLevel.DEBUG, R.string.msg_dc_askip_not_allowed),
         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_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/PgpDecryptVerifyOperation.java

@@ -31,6 +31,7 @@ import java.util.Iterator;
 
 import android.content.Context;
 import android.support.annotation.NonNull;
+import android.text.TextUtils;
 import android.webkit.MimeTypeMap;
 
 import org.openintents.openpgp.OpenPgpDecryptionResult;
@@ -201,6 +202,57 @@ public class PgpDecryptVerifyOperation extends BaseOperation<PgpDecryptVerifyInp
 
     }
 
+    private static class ArmorHeaders {
+        String charset = null;
+        Integer backupVersion = null;
+    }
+
+    private ArmorHeaders parseArmorHeaders(InputStream in, OperationLog log, int indent) {
+        ArmorHeaders armorHeaders = new ArmorHeaders();
+
+        // If the input stream is armored, and there is a charset specified, take a note for later
+        // https://tools.ietf.org/html/rfc4880#page56
+        if (in instanceof ArmoredInputStream) {
+            ArmoredInputStream aIn = (ArmoredInputStream) in;
+            if (aIn.getArmorHeaders() != null) {
+                for (String header : aIn.getArmorHeaders()) {
+                    String[] pieces = header.split(":", 2);
+                    if (pieces.length != 2
+                            || TextUtils.isEmpty(pieces[0])
+                            || TextUtils.isEmpty(pieces[1])) {
+                        continue;
+                    }
+
+                    switch (pieces[0].toLowerCase()) {
+                        case "charset": {
+                            armorHeaders.charset = pieces[1].trim();
+                            break;
+                        }
+                        case "backupversion": {
+                            try {
+                                armorHeaders.backupVersion = Integer.valueOf(pieces[1].trim());
+                            } catch (NumberFormatException e) {
+                                continue;
+                            }
+                            break;
+                        }
+                        default: {
+                            // continue;
+                        }
+                    }
+                }
+                if (armorHeaders.charset != null) {
+                    log.add(LogType.MSG_DC_CHARSET, indent, armorHeaders.charset);
+                }
+                if (armorHeaders.backupVersion != null) {
+                    log.add(LogType.MSG_DC_BACKUP_VERSION, indent, armorHeaders.backupVersion);
+                }
+            }
+        }
+
+        return armorHeaders;
+    }
+
     /** Decrypt and/or verify binary or ascii armored pgp data. */
     @NonNull
     private DecryptVerifyResult decryptVerify(
@@ -215,23 +267,12 @@ public class PgpDecryptVerifyOperation extends BaseOperation<PgpDecryptVerifyInp
         int currentProgress = 0;
         updateProgress(R.string.progress_reading_data, currentProgress, 100);
 
-        // If the input stream is armored, and there is a charset specified, take a note for later
+        // parse ASCII Armor headers
-        // https://tools.ietf.org/html/rfc4880#page56
+        ArmorHeaders armorHeaders = parseArmorHeaders(in, log, indent);
-        String charset = null;
+        String charset = armorHeaders.charset;
-        if (in instanceof ArmoredInputStream) {
+        boolean useBackupCode = false;
-            ArmoredInputStream aIn = (ArmoredInputStream) in;
+        if (armorHeaders.backupVersion != null && armorHeaders.backupVersion == 1) {
-            if (aIn.getArmorHeaders() != null) {
+            useBackupCode = true;
-                for (String header : aIn.getArmorHeaders()) {
-                    String[] pieces = header.split(":", 2);
-                    if (pieces.length == 2 && "charset".equalsIgnoreCase(pieces[0])) {
-                        charset = pieces[1].trim();
-                        break;
-                    }
-                }
-                if (charset != null) {
-                    log.add(LogType.MSG_DC_CHARSET, indent, charset);
-                }
-            }
         }
 
         OpenPgpDecryptionResultBuilder decryptionResultBuilder = new OpenPgpDecryptionResultBuilder();
@@ -245,7 +286,8 @@ public class PgpDecryptVerifyOperation extends BaseOperation<PgpDecryptVerifyInp
 
             if (obj instanceof PGPEncryptedDataList) {
                 esResult = handleEncryptedPacket(
-                        input, cryptoInput, (PGPEncryptedDataList) obj, log, indent, currentProgress);
+                        input, cryptoInput, (PGPEncryptedDataList) obj, log, indent,
+                        currentProgress, useBackupCode);
 
                 // if there is an error, nothing left to do here
                 if (esResult.errorResult != null) {
@@ -477,7 +519,7 @@ public class PgpDecryptVerifyOperation extends BaseOperation<PgpDecryptVerifyInp
     }
 
     private EncryptStreamResult handleEncryptedPacket(PgpDecryptVerifyInputParcel input, CryptoInputParcel cryptoInput,
-            PGPEncryptedDataList enc, OperationLog log, int indent, int currentProgress) throws PGPException {
+            PGPEncryptedDataList enc, OperationLog log, int indent, int currentProgress, boolean useBackupCode) throws PGPException {
 
         EncryptStreamResult result = new EncryptStreamResult();
 
@@ -609,8 +651,11 @@ public class PgpDecryptVerifyOperation extends BaseOperation<PgpDecryptVerifyInp
 
                     if (passphrase == null) {
                         log.add(LogType.MSG_DC_PENDING_PASSPHRASE, indent + 1);
+                        RequiredInputParcel requiredInputParcel = useBackupCode ?
+                                RequiredInputParcel.createRequiredBackupCode() :
+                                RequiredInputParcel.createRequiredSymmetricPassphrase();
                         return result.with(new DecryptVerifyResult(log,
-                                RequiredInputParcel.createRequiredSymmetricPassphrase(),
+                                requiredInputParcel,
                                 cryptoInput));
                     }
 
@@ -653,8 +698,10 @@ public class PgpDecryptVerifyOperation extends BaseOperation<PgpDecryptVerifyInp
                 result.cleartextStream = encryptedDataSymmetric.getDataStream(decryptorFactory);
             } catch (PGPDataValidationException e) {
                 log.add(LogType.MSG_DC_ERROR_SYM_PASSPHRASE, indent + 1);
-                return result.with(new DecryptVerifyResult(log,
+                RequiredInputParcel requiredInputParcel = useBackupCode ?
-                        RequiredInputParcel.createRequiredSymmetricPassphrase(), cryptoInput));
+                        RequiredInputParcel.createRequiredBackupCode() :
+                        RequiredInputParcel.createRequiredSymmetricPassphrase();
+                return result.with(new DecryptVerifyResult(log, requiredInputParcel, cryptoInput));
             }
 
             result.encryptedData = encryptedDataSymmetric;

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

@@ -44,6 +44,7 @@ public class PgpSignEncryptInputParcel implements Parcelable {
     protected boolean mDetachedSignature = false;
     protected boolean mHiddenRecipients = false;
     protected boolean mIntegrityProtected = true;
+    protected boolean mAddBackupHeader = false;
 
     public PgpSignEncryptInputParcel() {
 
@@ -70,6 +71,7 @@ public class PgpSignEncryptInputParcel implements Parcelable {
         mDetachedSignature = source.readInt() == 1;
         mHiddenRecipients = source.readInt() == 1;
         mIntegrityProtected = source.readInt() == 1;
+        mAddBackupHeader = source.readInt() == 1;
     }
 
     @Override
@@ -100,6 +102,7 @@ public class PgpSignEncryptInputParcel implements Parcelable {
         dest.writeInt(mDetachedSignature ? 1 : 0);
         dest.writeInt(mHiddenRecipients ? 1 : 0);
         dest.writeInt(mIntegrityProtected ? 1 : 0);
+        dest.writeInt(mAddBackupHeader ? 1 : 0);
     }
 
     public String getCharset() {
@@ -244,6 +247,15 @@ public class PgpSignEncryptInputParcel implements Parcelable {
         return this;
     }
 
+    public PgpSignEncryptInputParcel setAddBackupHeader(boolean addBackupHeader) {
+        this.mAddBackupHeader = addBackupHeader;
+        return this;
+    }
+
+    public boolean isAddBackupHeader() {
+        return mAddBackupHeader;
+    }
+
     public boolean isHiddenRecipients() {
         return mHiddenRecipients;
     }

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

@@ -149,6 +149,10 @@ public class PgpSignEncryptOperation extends BaseOperation {
             if (input.getCharset() != null) {
                 armorOut.setHeader("Charset", input.getCharset());
             }
+            // add proprietary header to indicate that this is a key backup
+            if (input.isAddBackupHeader()) {
+                armorOut.setHeader("BackupVersion", "1");
+            }
             out = armorOut;
         } else {
             out = outputStream;

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

@@ -14,8 +14,8 @@ import java.util.Date;
 public class RequiredInputParcel implements Parcelable {
 
     public enum RequiredInputType {
-        PASSPHRASE, PASSPHRASE_SYMMETRIC, NFC_SIGN, NFC_DECRYPT, NFC_MOVE_KEY_TO_CARD, ENABLE_ORBOT,
+        PASSPHRASE, PASSPHRASE_SYMMETRIC, BACKUP_CODE, NFC_SIGN, NFC_DECRYPT,
-        UPLOAD_FAIL_RETRY
+        NFC_MOVE_KEY_TO_CARD, ENABLE_ORBOT, UPLOAD_FAIL_RETRY
     }
 
     public Date mSignatureTime;
@@ -117,6 +117,11 @@ public class RequiredInputParcel implements Parcelable {
                 null, null, null, null, null);
     }
 
+    public static RequiredInputParcel createRequiredBackupCode() {
+        return new RequiredInputParcel(RequiredInputType.BACKUP_CODE,
+                null, null, null, null, null);
+    }
+
     public static RequiredInputParcel createRequiredPassphrase(
             RequiredInputParcel req) {
         return new RequiredInputParcel(RequiredInputType.PASSPHRASE,

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

@@ -1152,6 +1152,7 @@
     <string name="msg_dc_askip_not_allowed">"Data not encrypted with allowed key, skipping…"</string>
     <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_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>