Flutter Hive Reader

crc.dart

// crc.dart

import 'dart:typed_data';

/// Efficient CRC32 implementation
class Crc32 {
  /// Computes the CRC32 checksum of [bytes] using a previous [crc] value.
  static int compute(
    Uint8List bytes, {
    int crc = 0,
    int offset = 0,
    int? length,
  }) {
    crc = crc ^ 0xffffffff;

    length ??= bytes.length;

    for (var i = offset; i < offset + length; i++) {
      crc = _table[(crc ^ bytes[i]) & 0xff] ^ (crc >> 8);
    }

    return crc ^ 0xffffffff;
  }

  /// Precalculated CRC table.
  static const List<int> _table = [
    //
    0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f,
    0xe963a535, 0x9e6495a3, 0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988,
    0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91, 0x1db71064, 0x6ab020f2,
    0xf3b97148, 0x84be41de, 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7,
    0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9,
    0xfa0f3d63, 0x8d080df5, 0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172,
    0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b, 0x35b5a8fa, 0x42b2986c,
    0xdbbbc9d6, 0xacbcf940, 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59,
    0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423,
    0xcfba9599, 0xb8bda50f, 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924,
    0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d, 0x76dc4190, 0x01db7106,
    0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433,
    0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d,
    0x91646c97, 0xe6635c01, 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e,
    0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457, 0x65b0d9c6, 0x12b7e950,
    0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65,
    0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, 0x4adfa541, 0x3dd895d7,
    0xa4d1c46d, 0xd3d6f4fb, 0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0,
    0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9, 0x5005713c, 0x270241aa,
    0xbe0b1010, 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
    0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, 0x2eb40d81,
    0xb7bd5c3b, 0xc0ba6cad, 0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a,
    0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683, 0xe3630b12, 0x94643b84,
    0x0d6d6a3e, 0x7a6a5aa8, 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1,
    0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb,
    0x196c3671, 0x6e6b06e7, 0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc,
    0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5, 0xd6d6a3e8, 0xa1d1937e,
    0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b,
    0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55,
    0x316e8eef, 0x4669be79, 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236,
    0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, 0xc5ba3bbe, 0xb2bd0b28,
    0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d,
    0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, 0x9c0906a9, 0xeb0e363f,
    0x72076785, 0x05005713, 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38,
    0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242,
    0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777,
    0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, 0x8f659eff, 0xf862ae69,
    0x616bffd3, 0x166ccf45, 0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2,
    0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db, 0xaed16a4a, 0xd9d65adc,
    0x40df0b66, 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
    0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, 0xcdd70693,
    0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94,
    0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d
  ];
}

generic_adapter.dart

//generic_adapter.dart
import 'package:hive/hive.dart';

class GenericAdapter extends TypeAdapter<List> {
  @override
  final int typeId;

  GenericAdapter(this.typeId);

  @override
  List<dynamic> read(BinaryReader reader) {
    final numOfFields = reader.readByte();
    var list = List<dynamic>.filled(numOfFields, null, growable: true);

    for (var i = 0; i < numOfFields; i++) {
      list[reader.readByte()] = reader.read();
    }

    return list;
  }

  @override
  int get hashCode => typeId.hashCode;
  
  @override
  void write(BinaryWriter writer, List obj) {
    // No write needed
  }
}

main.dart

//main.dart
import 'package:eu_nviso_hivetest/generic_adapter.dart';
import 'package:flutter/material.dart';
import 'package:hive_flutter/hive_flutter.dart';
import 'package:path_provider/path_provider.dart';
import 'package:file_picker/file_picker.dart';
import 'package:hive/hive.dart';
import 'dart:convert';
import 'package:path/path.dart' as Path;
import 'package:flutter/services.dart';
import 'package:eu_nviso_hivetest/crc.dart';
import 'dart:io';
import 'dart:typed_data';
import 'dart:math';


void main() async {
  WidgetsFlutterBinding.ensureInitialized();
  final dir = await getApplicationDocumentsDirectory();
  Hive.init(dir.path);

  // Register the GenericAdapter for all available typeIds
  for(var i = 0; i<223; i++)
  {
    Hive.registerAdapter(GenericAdapter(i));
  }

  runApp(MaterialApp(home:MyApp()));

}


class MyApp extends StatefulWidget {
  @override
  _MyAppState createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {
  Map<dynamic, dynamic> hiveEntries = {};

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: Text('Hive Entries Viewer'),
        ),
        body: Column(
          children: [
            ElevatedButton(
              onPressed: () => _pickAndReadHiveFile(),
              child: Text('Browse Hive File'),
            ),
            Expanded(
              child: SingleChildScrollView(
                child: SingleChildScrollView(
                  scrollDirection: Axis.horizontal,
                  child: DataTable(
  columns: const [
    DataColumn(label: Text('Key')),
    DataColumn(label: Text('Value')),
  ],
  rows: hiveEntries.entries
      .map(
        (entry) => DataRow(cells: [
          DataCell(
            InkWell(
              onTap: () async {
                Clipboard.setData(ClipboardData(text: entry.key.toString()));
                  ScaffoldMessenger.of(context).showSnackBar(
                    SnackBar(
                      content: Text('Key copied to clipboard'),
                    ),
                  );
              },
              child: Text(entry.key.toString()),
            ),
          ),
          DataCell(
            InkWell(
              onTap: () {
                Clipboard.setData(ClipboardData(text: entry.value.toString()))
                    .then((_) {
                  ScaffoldMessenger.of(context).showSnackBar(
                    SnackBar(
                      content: Text('Value copied to clipboard'),
                    ),
                  );
                });
              },
              child: Text(entry.value.toString()),
            ),
          ),
        ]),
      )
      .toList(),
),

                ),
              ),
            ),
          ],
        ),
      ),
    );
  }

  Future<void> _pickAndReadHiveFile() async {
    FilePickerResult? result = await FilePicker.platform.pickFiles();

    if (result != null) {
      String? filePath = result.files.single.path;
      if (filePath != null) {
        TextEditingController passwordController = TextEditingController();
        // Show dialog to enter password
        showDialog(
          context: context,
          builder: (BuildContext context) {
            return AlertDialog(
              title: Text('Enter Password'),
              content: TextField(
                controller: passwordController,
                obscureText: true,
                decoration: InputDecoration(
                  hintText: 'Password',
                )
              ),
              actions: <Widget>[
                TextButton(
                  child: Text('OK'),
                  onPressed: () async {
                    String password = "";
                    if(passwordController.text.length > 0){
                      password = passwordController.text;
                    }
                    
                    Navigator.of(context).pop(); // Close the dialog
                    
                    await _readHiveFile(filePath, password); // Pass the password
                  },
                ),
              ],
            );
          },
        );
      }
    }
  }

  
   Future<void> _readHiveFile(String filePath, String password) async {

    

    File recoveredFile = await recoverHive(filePath, password.isEmpty ? null : HiveAesCipher(base64.decode(password)));

    String directory = Path.dirname(recoveredFile.path);
    String boxName = Path.basenameWithoutExtension(filePath);

    Hive.init(directory);

    Box<dynamic> box;
    if(password.isNotEmpty)
    {
      var passwordBytes = base64.decode(password);
      var encryptionCipher = HiveAesCipher(passwordBytes);
      box = await Hive.openBox<dynamic>(boxName, path: directory, encryptionCipher: encryptionCipher);
    }
    else{
      box = await Hive.openBox<dynamic>(boxName, path: directory);
    }

    setState(() {
      hiveEntries = Map<dynamic, dynamic>.from(box.toMap());
    });
    await box.close();
  }
}


Future<String> copyFileToTemp(String sourcePath) async {
  var sourceFile = File(sourcePath);
  // Generate a random subfolder name
  var rng = Random();
  var tempSubfolderName = "temp_${rng.nextInt(10000)}"; // Random subfolder name
  var tempDir = Directory.systemTemp.createTempSync(tempSubfolderName);
  
  // Create a File instance for the destination file in the new subfolder
  var tempFile = File('${tempDir.path}/${sourceFile.uri.pathSegments.last}');

  try {
    await sourceFile.copy(tempFile.path);
    print('File copied successfully to temporary directory: ${tempFile.path}');
  } catch (e) {
    print('Failed to copy file to temporary directory: $e');
  }
  return tempFile.path;
}

Future<File> recoverHive(originalFile, HiveAesCipher? cipher) async {
  var filePath = await copyFileToTemp(originalFile);
  var file = File(filePath);
  var bytes = await file.readAsBytes();
  int offset = 0;
  var allFrames = BytesBuilder();
  var keyNames = <String, int>{};
  var keyInts = [];


  while (offset < bytes.length) {
    var frameLength = ByteData.sublistView(bytes, offset, offset + 4).getUint32(0, Endian.little);
    var keyOffset = offset + 4; // Start looking for the key name right after the frame length
    var endOffset = offset + frameLength;
    if (bytes.length > keyOffset + 2) {

      Uint8List newKey;
      int frameResize;
      int keyLength;
      if(bytes[keyOffset] == 0x01){
        // Key is String
        keyLength = bytes[keyOffset + 1];
        var keyBytes = bytes.sublist(keyOffset + 2, keyOffset + 2 + keyLength);
        var keyName = String.fromCharCodes(keyBytes);

         if (keyNames.containsKey(keyName)) {
            keyNames[keyName] = keyNames[keyName]! + 1;
            keyName = "${keyName}_${keyNames[keyName]}";
          } else {
            keyNames[keyName] = 1;
          }
          var modifiedKeyBytes = Uint8List.fromList(keyName.codeUnits);
          var modifiedKeyLength = modifiedKeyBytes.length;

          // get bytes for TYPE + LENGTH + VALUE
          var bb = BytesBuilder();
          bb.addByte(0x01);
          bb.addByte(modifiedKeyLength);
          bb.add(modifiedKeyBytes);
          newKey = bb.toBytes();
          frameResize = modifiedKeyLength - keyLength;
          keyLength += 2; // add the length of the type

      }
      else{
        // Key is int
        keyLength = 5; // type + uint32
        var keyIndexOffset = keyOffset + 0x01;
        var keyInt = ByteData.sublistView(bytes, keyIndexOffset, keyIndexOffset + 4).getUint32(0, Endian.little);

        while(keyInts.contains(keyInt)){
          keyInt += 1;
        }
        keyInts.add(keyInt);

        var index = ByteData(4)..setUint32(0, keyInt, Endian.little);
        

        // get bytes for TYPE + index
        var bb = BytesBuilder();
        bb.addByte(0x00);
        bb.add(index.buffer.asUint8List());
        newKey = bb.toBytes();
        frameResize = 0;
      }

      // If there is no value, it's a delete frame, so we don't bother adding it again
      if(frameLength == keyLength + 8){ // 4 bytes for CRC, 4 bytes for frame length
        offset = endOffset;
        print("Dropping delete frame for " + newKey.toString());
        continue;
      }
      
      // Calculate new length of frame
      frameLength += frameResize;

      // Create a new frame bytes builder
      var frameBytes = BytesBuilder();
      
      // Prepare the frame length in ByteData and add it to the frame
      var frameLengthData = ByteData(4)..setUint32(0, frameLength, Endian.little);
      frameBytes.add(frameLengthData.buffer.asUint8List());

      // Add the new key
      frameBytes.add(newKey);
      
      // Add the rest of the frame after the original key. Don't include the CRC
      frameBytes.add(bytes.sublist(keyOffset + keyLength, endOffset-4));

      // Compute CRC using Hive's Crc32 class
      var newCrc = Crc32.compute(
        frameBytes.toBytes(),
        offset: 0,
        length: frameLength - 4,
        crc: cipher?.calculateKeyCrc() ?? 0,
      );

      // Write Crc code
      var newCrcBytes = Uint8List(4)..buffer.asByteData().setUint32(0, newCrc, Endian.little);
      frameBytes.add(newCrcBytes);

      // Update the overall frames with the modified frame
      allFrames.add(frameBytes.toBytes());
    }

    offset = endOffset; // Move to the next frame
  }

  var reconstructedBytes = allFrames.takeBytes();

  try {
    await file.writeAsBytes(reconstructedBytes);
    print('Bytes successfully written to temporary file: ${file.path}');
  } catch (e) {
    print('Failed to write bytes to temporary file: $e');
  }
  return file;
}

pubspec.yaml

name: eu_nviso_hivetest
description: "A new Flutter project."
publish_to: 'none' 

version: 1.0.0+1

environment:
  sdk: '>=3.3.0 <4.0.0'
dependencies:
  flutter:
    sdk: flutter 

  hive: ^2.2.3
  hive_flutter: ^1.1.0
  isar_flutter_libs: ^3.1.0+1
  path_provider: ^2.1.2
  file_picker: ^6.1.1
  path: ^1.9.0
  flutter_secure_storage: ^9.0.0
  cupertino_icons: ^1.0.6

dev_dependencies:
  flutter_test:
    sdk: flutter

  hive_generator: ^1.1.0 
  build_runner: ^2.0.1
  flutter_lints: ^3.0.0
flutter:
  uses-material-design: true