Revert "fix: unify encryption across platforms (#3470)" (#3634)

diff --git a/cw_core/lib/encryption_file_utils.dart b/cw_core/lib/encryption_file_utils.dart
index 54729b73..72a601bc 100644
--- a/cw_core/lib/encryption_file_utils.dart
+++ b/cw_core/lib/encryption_file_utils.dart
@@ -1,34 +1,41 @@
+import 'dart:io';
+import 'dart:typed_data';
 import 'package:cw_core/utils/file.dart' as file;
+import 'package:cake_backup/backup.dart' as cwb;
 
-EncryptionFileUtils encryptionFileUtilsFor(bool isDirect) =>
-    XChaCha20MigratingEncryptionFileUtils(isDirect: isDirect);
+EncryptionFileUtils encryptionFileUtilsFor(bool direct) =>
+    direct ? XChaCha20EncryptionFileUtils() : Salsa20EncryhptionFileUtils();
 
 abstract class EncryptionFileUtils {
   Future<void> write({required String path, required String password, required String data});
   Future<String> read({required String path, required String password});
 }
 
-class XChaCha20MigratingEncryptionFileUtils extends EncryptionFileUtils {
-  XChaCha20MigratingEncryptionFileUtils({required this.isDirect});
+class Salsa20EncryhptionFileUtils extends EncryptionFileUtils {
+  // Requires legacy complex key + iv as password
+  @override
+  Future<void> write(
+          {required String path, required String password, required String data}) async =>
+      await file.write(path: path, password: password, data: data);
 
-  final bool isDirect;
+  // Requires legacy complex key + iv as password
+  @override
+  Future<String> read({required String path, required String password}) async =>
+      await file.read(path: path, password: password);
+}
 
+class XChaCha20EncryptionFileUtils extends EncryptionFileUtils {
   @override
-  Future<void> write({required String path, required String password, required String data}) {
-    return file.write(
-      path: path,
-      password: password,
-      data: data,
-      highEntropyPassphrase: !isDirect,
-    );
+  Future<void> write({required String path, required String password, required String data}) async {
+    final encrypted = await cwb.encrypt(password, Uint8List.fromList(data.codeUnits));
+    await File(path).writeAsBytes(encrypted);
   }
 
   @override
-  Future<String> read({required String path, required String password}) {
-    return file.read(
-      path: path,
-      password: password,
-      highEntropyPassphrase: !isDirect,
-    );
+  Future<String> read({required String path, required String password}) async {
+    final file = File(path);
+    final encrypted = await file.readAsBytes();
+    final bytes = await cwb.decrypt(password, encrypted);
+    return String.fromCharCodes(bytes);
   }
 }
diff --git a/cw_core/lib/key.dart b/cw_core/lib/key.dart
index 99570bc7..383cbfff 100644
--- a/cw_core/lib/key.dart
+++ b/cw_core/lib/key.dart
@@ -1,8 +1,35 @@
 import 'package:encrypt/encrypt.dart' as encrypt;
 
+const ivEncodedStringLength = 12;
+
 String generateKey() {
   final key = encrypt.Key.fromSecureRandom(512);
   final iv = encrypt.IV.fromSecureRandom(8);
 
   return key.base64 + iv.base64;
 }
+
+List<String> extractKeys(String key) {
+  final _key = key.substring(0, key.length - ivEncodedStringLength);
+  final iv = key.substring(key.length - ivEncodedStringLength);
+
+  return [_key, iv];
+}
+
+Future<String> encode(
+    {required encrypt.Key key, required encrypt.IV iv, required String data}) async {
+  final encrypter = encrypt.Encrypter(encrypt.Salsa20(key));
+  final encrypted = encrypter.encrypt(data, iv: iv);
+
+  return encrypted.base64;
+}
+
+Future<String> decode({required String password, required String data}) async {
+  final keys = extractKeys(password);
+  final key = encrypt.Key.fromBase64(keys.first);
+  final iv = encrypt.IV.fromBase64(keys.last);
+  final encrypter = encrypt.Encrypter(encrypt.Salsa20(key));
+  final encrypted = encrypter.decrypt64(data, iv: iv);
+
+  return encrypted;
+}
diff --git a/cw_core/lib/utils/file.dart b/cw_core/lib/utils/file.dart
index 3ad3165d..72fc9485 100644
--- a/cw_core/lib/utils/file.dart
+++ b/cw_core/lib/utils/file.dart
@@ -1,84 +1,21 @@
-import 'dart:convert';
 import 'dart:io';
-import 'dart:typed_data';
-
-import 'package:cake_backup/backup.dart' as cwb;
+import 'package:cw_core/key.dart';
 import 'package:encrypt/encrypt.dart' as encrypt;
 
-const _ivEncodedStringLength = 12;
-
-Future<void> write({
-  required String path,
-  required String password,
-  required String data,
-  bool? highEntropyPassphrase,
-}) async {
-  await _writeXChaCha20(
-    path: path,
-    password: password,
-    data: data,
-    highEntropyPassphrase: highEntropyPassphrase ?? !Platform.isLinux,
-  );
-}
-
-Future<String> read({
-  required String path,
-  required String password,
-  bool? highEntropyPassphrase,
-}) async {
-  final useHighEntropy = highEntropyPassphrase ?? !Platform.isLinux;
-  try {
-    return await _readXChaCha20(path: path, password: password);
-  } catch (e) {
-    final encrypted = await File(path).readAsBytes();
-    if (encrypted.isNotEmpty &&
-        (encrypted[0] == cwb.lowEntropyVersion || encrypted[0] == cwb.highEntropyVersion)) {
-      rethrow;
-    }
+Future<void> write({required String path, required String password, required String data}) async =>
+    writeData(path: path, password: password, data: data);
 
-    final String data;
-    try {
-      data = await _readLegacy(path: path, password: password);
-    } catch (_) {
-      throw Exception('Failed to decrypt legacy file: invalid password or corrupted data');
-    }
-    if (data.isEmpty) {
-      throw Exception('Failed to read data');
-    }
-
-    // Salsa20 is unauthenticated, so a wrong password decrypts to garbage instead of
-    // failing. Every payload written here is a JSON object with at least one key, so a
-    // correctly decrypted file always starts with '{"' and anything else is a bad
-    // password.
-    // There's 1 in 2^16 chance that this will be a false positive, but check later
-    // prevents any damage to the file caused by re-encryption.
-    if (!data.startsWith('{"')) {
-      throw Exception('Failed to decrypt legacy file: invalid password or corrupted data');
-    }
-
-    if (_isJson(data)) {
-      await _writeXChaCha20(
-        path: path,
-        password: password,
-        data: data,
-        highEntropyPassphrase: useHighEntropy,
-      );
-    }
-
-    return data;
-  }
-}
-
-bool _isJson(String data) {
-  try {
-    json.decode(data);
-    return true;
-  } catch (_) {
-    return false;
-  }
+Future<void> writeData(
+    {required String path, required String password, required String data}) async {
+  final keys = extractKeys(password);
+  final key = encrypt.Key.fromBase64(keys.first);
+  final iv = encrypt.IV.fromBase64(keys.last);
+  final encrypted = await encode(key: key, iv: iv, data: data);
+  final f = File(path);
+  f.writeAsStringSync(encrypted);
 }
 
-Future<String> _readLegacy({required String path, required String password}) async {
+Future<String> read({required String path, required String password}) async {
   final file = File(path);
 
   if (!file.existsSync()) {
@@ -87,57 +24,5 @@ Future<String> _readLegacy({required String path, required String password}) asy
 
   final encrypted = file.readAsStringSync();
 
-  return _decode(password: password, data: encrypted);
-}
-
-Future<void> _writeXChaCha20({
-  required String path,
-  required String password,
-  required String data,
-  required bool highEntropyPassphrase,
-}) async {
-  final encrypted = await cwb.encrypt(
-    password,
-    Uint8List.fromList(utf8.encode(data)),
-    highEntropyPassphrase: highEntropyPassphrase,
-  );
-
-  final tmpFile = File('$path.tmp');
-  tmpFile.writeAsBytesSync(encrypted, flush: true);
-  tmpFile.renameSync(path);
-}
-
-Future<String> _readXChaCha20({
-  required String path,
-  required String password,
-}) async {
-  final encrypted = await File(path).readAsBytes();
-  final bytes = await cwb.decrypt(password, encrypted);
-  return _decodeUtf8(bytes);
-}
-
-// Linux wallets written by the old XChaCha20EncryptionFileUtils stored one byte per
-// UTF-16 code unit, so bytes above 0x7F in those files are Latin-1 rather than UTF-8.
-String _decodeUtf8(Uint8List bytes) {
-  try {
-    return utf8.decode(bytes);
-  } on FormatException {
-    return String.fromCharCodes(bytes);
-  }
-}
-
-List<String> _extractKeys(String key) {
-  final k = key.substring(0, key.length - _ivEncodedStringLength);
-  final iv = key.substring(key.length - _ivEncodedStringLength);
-
-  return [k, iv];
-}
-
-Future<String> _decode({required String password, required String data}) async {
-  final keys = _extractKeys(password);
-  final key = encrypt.Key.fromBase64(keys.first);
-  final iv = encrypt.IV.fromBase64(keys.last);
-  final encrypter = encrypt.Encrypter(encrypt.Salsa20(key));
-
-  return encrypter.decrypt64(data, iv: iv);
+  return decode(password: password, data: encrypted);
 }
diff --git a/cw_core/lib/wallet_service.dart b/cw_core/lib/wallet_service.dart
index d69300d1..72ea98a9 100644
--- a/cw_core/lib/wallet_service.dart
+++ b/cw_core/lib/wallet_service.dart
@@ -1,18 +1,17 @@
 import "dart:convert";
 import "dart:io";
 
-import 'package:cw_core/encryption_file_utils.dart';
-import 'package:cw_core/imported_nft.dart';
-import 'package:cw_core/pathForWallet.dart';
-import 'package:cw_core/spl_token.dart';
-import 'package:cw_core/tron_token.dart';
-import 'package:cw_core/utils/print_verbose.dart';
-import 'package:cw_core/wallet_keys_file.dart';
-import 'package:cw_core/wallet_base.dart';
-import 'package:cw_core/wallet_credentials.dart';
-import 'package:cw_core/wallet_info.dart';
-import 'package:cw_core/wallet_type.dart';
-import 'package:path/path.dart' as p;
+import "package:cw_core/imported_nft.dart";
+import "package:cw_core/pathForWallet.dart";
+import "package:cw_core/spl_token.dart";
+import "package:cw_core/tron_token.dart";
+import "package:cw_core/utils/file.dart";
+import "package:cw_core/utils/print_verbose.dart";
+import "package:cw_core/wallet_base.dart";
+import "package:cw_core/wallet_credentials.dart";
+import "package:cw_core/wallet_info.dart";
+import "package:cw_core/wallet_type.dart";
+import "package:path/path.dart" as p;
 
 abstract class WalletService<N extends WalletCredentials, RFS extends WalletCredentials,
     RFK extends WalletCredentials, RFH extends WalletCredentials> {
@@ -96,15 +95,8 @@ abstract class WalletService<N extends WalletCredentials, RFS extends WalletCred
 
   Future<String> getSeeds(String name, String password, WalletType type) async {
     try {
-      final encryption = encryptionFileUtilsFor(Platform.isLinux);
-
-      if (await WalletKeysFile.hasKeysFile(name, type)) {
-        final keysData = await WalletKeysFile.readKeysFile(name, type, password, encryption);
-        return keysData.mnemonic ?? keysData.altMnemonic ?? keysData.privateKey ?? '';
-      }
-
       final path = await pathForWallet(name: name, type: type);
-      final jsonSource = await encryption.read(path: path, password: password);
+      final jsonSource = await read(path: path, password: password);
       try {
         final data = json.decode(jsonSource) as Map;
         return data["mnemonic"] as String? ?? "";
diff --git a/cw_core/pubspec.yaml b/cw_core/pubspec.yaml
index b7843f4b..38a4e9a4 100644
--- a/cw_core/pubspec.yaml
+++ b/cw_core/pubspec.yaml
@@ -22,7 +22,8 @@ dependencies:
   cake_backup:
     git:
       url: https://github.com/cake-tech/cake_backup.git
-      ref: b5d86a2a21e1c186cd0baa4df1f3a4f3f9413056
+      ref: main
+      version: 1.0.0
   socks5_proxy:
     git:
       url: https://github.com/LacticWhale/socks_dart
diff --git a/cw_core/test/encryption_file_utils_test.dart b/cw_core/test/encryption_file_utils_test.dart
deleted file mode 100644
index bfd840f0..00000000
--- a/cw_core/test/encryption_file_utils_test.dart
+++ /dev/null
@@ -1,380 +0,0 @@
-import 'dart:convert';
-import 'dart:io';
-import 'dart:typed_data';
-
-import 'package:cake_backup/backup.dart' as cwb;
-import 'package:cw_core/encryption_file_utils.dart';
-import 'package:cw_core/key.dart';
-import 'package:cw_core/utils/file.dart' as encrypted_file;
-import 'package:cw_core/wallet_keys_file.dart';
-import 'package:encrypt/encrypt.dart' as encrypt;
-import 'package:flutter_test/flutter_test.dart';
-
-void main() {
-  late Directory tmpDir;
-
-  setUp(() {
-    tmpDir = Directory.systemTemp.createTempSync('cw_enc_');
-  });
-
-  tearDown(() {
-    if (tmpDir.existsSync()) {
-      tmpDir.deleteSync(recursive: true);
-    }
-  });
-
-  String path([String name = 'wallet.json']) => '${tmpDir.path}/$name';
-
-  const walletJson = '{"mnemonic":"abandon ability able","privateKey":null}';
-
-  group('XChaCha20 round-trip', () {
-    test('writes and reads JSON with a generated high-entropy password', () async {
-      final password = generateKey();
-      await encrypted_file.write(
-        path: path(),
-        password: password,
-        data: walletJson,
-        highEntropyPassphrase: true,
-      );
-
-      expect(await encrypted_file.read(path: path(), password: password), walletJson);
-      expect(File('${path()}.tmp').existsSync(), isFalse);
-    });
-
-    test('uses high-entropy (v3) vs low-entropy (v2) version bytes', () async {
-      final password = generateKey();
-
-      await encrypted_file.write(
-        path: path('high'),
-        password: password,
-        data: walletJson,
-        highEntropyPassphrase: true,
-      );
-      expect(File(path('high')).readAsBytesSync().first, cwb.highEntropyVersion);
-
-      await encrypted_file.write(
-        path: path('low'),
-        password: password,
-        data: walletJson,
-        highEntropyPassphrase: false,
-      );
-      expect(File(path('low')).readAsBytesSync().first, cwb.lowEntropyVersion);
-
-      expect(await encrypted_file.read(path: path('high'), password: password), walletJson);
-      expect(await encrypted_file.read(path: path('low'), password: password), walletJson);
-    });
-
-    test('read ignores highEntropyPassphrase because version is in the file', () async {
-      final password = generateKey();
-      await encrypted_file.write(
-        path: path(),
-        password: password,
-        data: walletJson,
-        highEntropyPassphrase: true,
-      );
-
-      expect(
-        await encrypted_file.read(
-          path: path(),
-          password: password,
-          highEntropyPassphrase: false,
-        ),
-        walletJson,
-      );
-    });
-
-    test('round-trips UTF-8 JSON with non-ASCII characters', () async {
-      final password = generateKey();
-      const data = '{"name":"Café","mnemonic":"abandon"}';
-      await encrypted_file.write(
-        path: path(),
-        password: password,
-        data: data,
-        highEntropyPassphrase: true,
-      );
-
-      expect(await encrypted_file.read(path: path(), password: password), data);
-    });
-
-    test('wrong password does not fall back to Salsa20 or rewrite the file', () async {
-      final password = generateKey();
-      await encrypted_file.write(
-        path: path(),
-        password: password,
-        data: walletJson,
-        highEntropyPassphrase: true,
-      );
-      final before = File(path()).readAsBytesSync();
-
-      await expectLater(
-        encrypted_file.read(path: path(), password: generateKey()),
-        throwsA(anything),
-      );
-      expect(File(path()).readAsBytesSync(), before);
-    });
-
-    test('corrupt XChaCha20 blob is not treated as a legacy Salsa20 file', () async {
-      final password = generateKey();
-      await encrypted_file.write(
-        path: path(),
-        password: password,
-        data: walletJson,
-        highEntropyPassphrase: true,
-      );
-      final bytes = File(path()).readAsBytesSync();
-      bytes[bytes.length - 1] = bytes[bytes.length - 1] ^ 0xFF;
-      File(path()).writeAsBytesSync(bytes);
-
-      await expectLater(
-        encrypted_file.read(path: path(), password: password),
-        throwsA(anything),
-      );
-      expect(File(path()).readAsBytesSync().first, cwb.highEntropyVersion);
-    });
-  });
-
-  group('encryptionFileUtilsFor', () {
-    test('isDirect=false (generated password) writes high-entropy v3', () async {
-      final password = generateKey();
-      final encryption = encryptionFileUtilsFor(false);
-      await encryption.write(path: path(), password: password, data: walletJson);
-
-      expect(File(path()).readAsBytesSync().first, cwb.highEntropyVersion);
-      expect(await encryption.read(path: path(), password: password), walletJson);
-    });
-
-    test('isDirect=true (user password) writes low-entropy v2', () async {
-      const password = 'user-chosen-passphrase';
-      final encryption = encryptionFileUtilsFor(true);
-      await encryption.write(path: path(), password: password, data: walletJson);
-
-      expect(File(path()).readAsBytesSync().first, cwb.lowEntropyVersion);
-      expect(await encryption.read(path: path(), password: password), walletJson);
-    });
-
-    test('WalletKeysData JSON survives a write/read used by getSeeds', () async {
-      final password = generateKey();
-      final keys = WalletKeysData(
-        mnemonic: 'abandon ability able about above absent absorb abstract',
-        privateKey: 'deadbeef',
-      );
-      final encryption = encryptionFileUtilsFor(false);
-      await encryption.write(path: path(), password: password, data: keys.toJSON());
-
-      final decoded = json.decode(await encryption.read(path: path(), password: password))
-          as Map<String, dynamic>;
-      final restored = WalletKeysData.fromJSON(decoded);
-      expect(restored.mnemonic, keys.mnemonic);
-      expect(restored.privateKey, keys.privateKey);
-    });
-  });
-
-  group('legacy Salsa20 migration', () {
-    test('reads a Salsa20 wallet file and re-encrypts it as XChaCha20', () async {
-      final password = generateKey();
-      File(path()).writeAsStringSync(_salsa20Encrypt(password, walletJson));
-      expect(File(path()).readAsBytesSync().first, isNot(cwb.lowEntropyVersion));
-      expect(File(path()).readAsBytesSync().first, isNot(cwb.highEntropyVersion));
-
-      final result = await encrypted_file.read(
-        path: path(),
-        password: password,
-        highEntropyPassphrase: true,
-      );
-
-      expect(result, walletJson);
-      expect(File(path()).readAsBytesSync().first, cwb.highEntropyVersion);
-      expect(await encrypted_file.read(path: path(), password: password), walletJson);
-    });
-
-    test('migrated file can be opened with EncryptionFileUtils', () async {
-      final password = generateKey();
-      File(path()).writeAsStringSync(_salsa20Encrypt(password, walletJson));
-
-      final encryption = encryptionFileUtilsFor(false);
-      expect(await encryption.read(path: path(), password: password), walletJson);
-      expect(await encryption.read(path: path(), password: password), walletJson);
-    });
-
-    test('wrong password does not rewrite the Salsa20 file', () async {
-      final password = generateKey();
-      final salsa = _salsa20Encrypt(password, walletJson);
-      File(path()).writeAsStringSync(salsa);
-
-      await expectLater(
-        encrypted_file.read(path: path(), password: generateKey()),
-        throwsLegacyDecryptError,
-      );
-      expect(File(path()).readAsStringSync(), salsa);
-    });
-
-    test('short or malformed password does not leak _readLegacy errors', () async {
-      final password = generateKey();
-      final salsa = _salsa20Encrypt(password, walletJson);
-      File(path()).writeAsStringSync(salsa);
-
-      await expectLater(
-        encrypted_file.read(path: path(), password: 'user-pass'),
-        throwsLegacyDecryptError,
-      );
-      expect(File(path()).readAsStringSync(), salsa);
-    });
-
-    test('corrupt non-base64 file does not leak _readLegacy errors', () async {
-      File(path()).writeAsStringSync('not-valid-base64!!!');
-
-      await expectLater(
-        encrypted_file.read(path: path(), password: generateKey()),
-        throwsLegacyDecryptError,
-      );
-      expect(File(path()).readAsStringSync(), 'not-valid-base64!!!');
-    });
-
-    test('invalid UTF-8 legacy bytes do not leak _readLegacy errors', () async {
-      File(path()).writeAsBytesSync(const [0x00, 0xFF, 0xFE, 0x01]);
-
-      await expectLater(
-        encrypted_file.read(path: path(), password: generateKey()),
-        throwsLegacyDecryptError,
-      );
-      expect(File(path()).readAsBytesSync(), const [0x00, 0xFF, 0xFE, 0x01]);
-    });
-
-    test('rejects Salsa20 plaintext that does not start with {"', () async {
-      final password = generateKey();
-      File(path()).writeAsStringSync(_salsa20Encrypt(password, 'not-json-payload'));
-
-      await expectLater(
-        encrypted_file.read(path: path(), password: password),
-        throwsLegacyDecryptError,
-      );
-      expect(File(path()).readAsBytesSync().first, isNot(cwb.highEntropyVersion));
-      expect(File(path()).readAsBytesSync().first, isNot(cwb.lowEntropyVersion));
-    });
-
-    test('does not re-encrypt Salsa20 data that starts with {" but is not JSON', () async {
-      final password = generateKey();
-      const garbage = '{"not valid json';
-      File(path()).writeAsStringSync(_salsa20Encrypt(password, garbage));
-
-      expect(await encrypted_file.read(path: path(), password: password), garbage);
-      expect(File(path()).readAsBytesSync().first, isNot(cwb.highEntropyVersion));
-      expect(File(path()).readAsBytesSync().first, isNot(cwb.lowEntropyVersion));
-    });
-
-    test(
-      'wrong password that decrypts to {" does not rewrite the file',
-      () async {
-        final password = generateKey();
-        final salsa = _salsa20Encrypt(password, walletJson);
-        File(path()).writeAsStringSync(salsa);
-
-        final collision = _findWrongPasswordWithJsonObjectPrefix(salsa);
-        expect(collision, isNot(password));
-        expect(_salsa20Decrypt(collision, salsa).startsWith('{"'), isTrue);
-        expect(() => json.decode(_salsa20Decrypt(collision, salsa)), throwsA(anything));
-
-        final result = await encrypted_file.read(path: path(), password: collision);
-
-        expect(result.startsWith('{"'), isTrue);
-        expect(result, isNot(walletJson));
-        expect(File(path()).readAsStringSync(), salsa);
-      },
-    );
-  });
-
-  group('legacy Linux XChaCha20 Latin-1 payloads', () {
-    test('decodes files stored as one byte per UTF-16 code unit', () async {
-      final password = generateKey();
-      const data = '{"name":"Café","mnemonic":"abandon"}';
-      // Old XChaCha20EncryptionFileUtils used String.codeUnits instead of utf8.encode.
-      final encrypted = await cwb.encrypt(
-        password,
-        Uint8List.fromList(data.codeUnits),
-        highEntropyPassphrase: true,
-      );
-      File(path()).writeAsBytesSync(encrypted);
-
-      expect(await encrypted_file.read(path: path(), password: password), data);
-    });
-  });
-
-  group('generateKey', () {
-    test('produces unique passwords that still encrypt and decrypt', () async {
-      final a = generateKey();
-      final b = generateKey();
-      expect(a, isNot(b));
-      expect(a.length, greaterThan(12));
-
-      await encrypted_file.write(
-        path: path(),
-        password: a,
-        data: walletJson,
-        highEntropyPassphrase: true,
-      );
-      expect(await encrypted_file.read(path: path(), password: a), walletJson);
-    });
-  });
-}
-
-final throwsLegacyDecryptError = throwsA(
-  isA<Exception>().having(
-    (e) => e.toString(),
-    'message',
-    contains('Failed to decrypt legacy file'),
-  ),
-);
-
-({encrypt.Key key, encrypt.IV iv}) _salsa20Keys(String password) {
-  const ivEncodedStringLength = 12;
-  return (
-    key: encrypt.Key.fromBase64(password.substring(0, password.length - ivEncodedStringLength)),
-    iv: encrypt.IV.fromBase64(password.substring(password.length - ivEncodedStringLength)),
-  );
-}
-
-encrypt.Encrypter _salsa20(String password) {
-  final keys = _salsa20Keys(password);
-  return encrypt.Encrypter(encrypt.Salsa20(keys.key));
-}
-
-String _salsa20Encrypt(String password, String data) {
-  final keys = _salsa20Keys(password);
-  return _salsa20(password).encrypt(data, iv: keys.iv).base64;
-}
-
-String _salsa20Decrypt(String password, String data) {
-  final keys = _salsa20Keys(password);
-  return _salsa20(password).decrypt64(data, iv: keys.iv);
-}
-
-List<int> _salsa20DecryptBytes(String password, String data) {
-  final keys = _salsa20Keys(password);
-  return _salsa20(password).decryptBytes(encrypt.Encrypted.fromBase64(data), iv: keys.iv);
-}
-
-String _passwordFromNonce(int nonce) {
-  final ivBytes = Uint8List(8);
-  ivBytes.buffer.asByteData().setUint64(0, nonce, Endian.little);
-  return encrypt.Key(Uint8List(32)).base64 + encrypt.IV(ivBytes).base64;
-}
-
-/// Salsa20 has no MAC, so a wrong key decrypts to garbage. The first two bytes
-/// are `{"` about once in 2^16 tries; keep going until that happens, then skip
-/// the much rarer case where the garbage is also valid JSON (that would rewrite).
-String _findWrongPasswordWithJsonObjectPrefix(String ciphertext) {
-  const maxAttempts = 1 << 20;
-  for (var nonce = 0; nonce < maxAttempts; nonce++) {
-    final candidate = _passwordFromNonce(nonce);
-    final bytes = _salsa20DecryptBytes(candidate, ciphertext);
-    if (bytes.length < 2 || bytes[0] != 0x7b || bytes[1] != 0x22) {
-      continue;
-    }
-    try {
-      json.decode(_salsa20Decrypt(candidate, ciphertext));
-    } catch (_) {
-      return candidate;
-    }
-  }
-  fail('no Salsa20 {" prefix collision in $maxAttempts attempts');
-}
diff --git a/lib/view_model/dashboard/dashboard_view_model.dart b/lib/view_model/dashboard/dashboard_view_model.dart
index 1c71ce11..f428b354 100644
--- a/lib/view_model/dashboard/dashboard_view_model.dart
+++ b/lib/view_model/dashboard/dashboard_view_model.dart
@@ -55,7 +55,7 @@ import 'package:cw_core/pathForWallet.dart';
 import 'package:cw_core/sync_status.dart';
 import 'package:cw_core/transaction_history.dart';
 import 'package:cw_core/transaction_info.dart';
-import 'package:cw_core/encryption_file_utils.dart';
+import 'package:cw_core/utils/file.dart';
 import 'package:cw_core/utils/print_verbose.dart';
 import 'package:cw_core/wallet_base.dart';
 import 'package:cw_core/wallet_info.dart';
@@ -1515,8 +1515,7 @@ abstract class DashboardViewModelBase with Store {
         if (walletInfo.type == WalletType.bitcoin) {
           final password = await keyService.getWalletPassword(walletName: walletInfo.name);
           final path = await pathForWallet(name: walletInfo.name, type: walletInfo.type);
-          final encryption = encryptionFileUtilsFor(SettingsStoreBase.walletPasswordDirectInput);
-          final jsonSource = await encryption.read(path: path, password: password);
+          final jsonSource = await read(path: path, password: password);
           final data = json.decode(jsonSource) as Map;
           final mnemonic = data['mnemonic'] as String?;
 
diff --git a/pubspec.lock b/pubspec.lock
index 4cd50bf7..f37ff20e 100644
--- a/pubspec.lock
+++ b/pubspec.lock
@@ -388,8 +388,8 @@ packages:
     dependency: "direct main"
     description:
       path: "."
-      ref: b5d86a2a21e1c186cd0baa4df1f3a4f3f9413056
-      resolved-ref: b5d86a2a21e1c186cd0baa4df1f3a4f3f9413056
+      ref: "3aba867dcab6737f6707782f5db15d71f303db38"
+      resolved-ref: "3aba867dcab6737f6707782f5db15d71f303db38"
       url: "https://github.com/cake-tech/cake_backup.git"
     source: git
     version: "1.0.0+1"
diff --git a/pubspec_base.yaml b/pubspec_base.yaml
index 52a41ad6..e8c75f95 100644
--- a/pubspec_base.yaml
+++ b/pubspec_base.yaml
@@ -85,7 +85,7 @@ dependencies:
   cake_backup:
     git:
       url: https://github.com/cake-tech/cake_backup.git
-      ref: b5d86a2a21e1c186cd0baa4df1f3a4f3f9413056
+      ref: 3aba867dcab6737f6707782f5db15d71f303db38
   flutter_plugin_android_lifecycle: 2.0.23
   path_provider_android: ^2.2.1
   shared_preferences_android: ^2.4.8
@@ -247,7 +247,7 @@ dev_dependencies:
 #   cake_backup:
 #     git:
 #       url: https://github.com/cake-tech/cake_backup.git
-#       ref: b5d86a2a21e1c186cd0baa4df1f3a4f3f9413056
+#       ref: 3aba867dcab6737f6707782f5db15d71f303db38
 
 flutter_icons:
   image_path: "assets/images/app_logo.png"
diff --git a/pubspec_overrides.yaml b/pubspec_overrides.yaml
index 2bf9d2ce..15910a4f 100644
--- a/pubspec_overrides.yaml
+++ b/pubspec_overrides.yaml
@@ -174,7 +174,7 @@ dependency_overrides:
   cake_backup:
     git:
       url: https://github.com/cake-tech/cake_backup.git
-      ref: b5d86a2a21e1c186cd0baa4df1f3a4f3f9413056
+      ref: 3aba867dcab6737f6707782f5db15d71f303db38
   characters:
     git:
       url: https://github.com/dart-lang/core