refactor: use OpenSSL for file e2ee

lib/src/event.dart

@@ -20,7 +20,6 @@ import 'dart:convert';
 import 'dart:typed_data';
 
 import 'package:http/http.dart' as http;
-import 'package:matrix_file_e2ee/matrix_file_e2ee.dart';
 
 import '../famedlysdk.dart';
 import 'database/database.dart' show DbRoomState, DbEvent;
@@ -29,6 +28,7 @@ import 'utils/matrix_localizations.dart';
 import 'utils/receipt.dart';
 import 'utils/run_in_background.dart';
 import 'utils/event_localizations.dart';
+import 'utils/crypto/encrypted_file.dart';
 
 abstract class RelationshipTypes {
   static const String reply = 'm.in_reply_to';

lib/src/room.dart

@@ -21,7 +21,6 @@ import 'dart:convert';
 
 import 'package:famedlysdk/src/utils/space_child.dart';
 import 'package:html_unescape/html_unescape.dart';
-import 'package:matrix_file_e2ee/matrix_file_e2ee.dart';
 
 import '../famedlysdk.dart';
 import 'client.dart';
@@ -29,6 +28,7 @@ import 'database/database.dart' show DbRoom;
 import 'event.dart';
 import 'timeline.dart';
 import 'user.dart';
+import 'utils/crypto/encrypted_file.dart';
 import 'utils/event_update.dart';
 import 'utils/markdown.dart';
 import 'utils/marked_unread.dart';

lib/src/utils/crypto/encrypted_file.dart

@@ -0,0 +1,40 @@
+import 'dart:typed_data';
+import 'dart:convert';
+
+import 'crypto.dart';
+
+class EncryptedFile {
+  EncryptedFile({
+    this.data,
+    this.k,
+    this.iv,
+    this.sha256,
+  });
+  Uint8List data;
+  String k;
+  String iv;
+  String sha256;
+}
+
+Future<EncryptedFile> encryptFile(Uint8List input) async {
+  final key = secureRandomBytes(32);
+  final iv = secureRandomBytes(16);
+  final data = await aesCtr.encrypt(input, key, iv);
+  final hash = await sha256(data);
+  return EncryptedFile(
+    data: data,
+    k: base64Url.encode(key).replaceAll('=', ''),
+    iv: base64.encode(iv).replaceAll('=', ''),
+    sha256: base64.encode(hash).replaceAll('=', ''),
+  );
+}
+
+Future<Uint8List> decryptFile(EncryptedFile input) async {
+  if (base64.encode(await sha256(input.data)) != base64.normalize(input.sha256)) {
+    return null;
+  }
+
+  final key = base64.decode(base64.normalize(input.k));
+  final iv = base64.decode(base64.normalize(input.iv));
+  return await aesCtr.encrypt(input.data, key, iv);
+}

lib/src/utils/crypto/ffi.dart

@@ -63,3 +63,14 @@ final EVP_CIPHER_CTX_free = libcrypto.lookupFunction<
   Pointer<NativeType> Function(Pointer<NativeType> ctx),
   Pointer<NativeType> Function(Pointer<NativeType> ctx)
 >('EVP_CIPHER_CTX_free');
+
+final EVP_Digest = libcrypto.lookupFunction<
+  IntPtr Function(Pointer<Uint8> data, IntPtr len, Pointer<Uint8> hash, Pointer<IntPtr> hsize, Pointer<NativeType> alg, Pointer<NativeType> engine),
+  int Function(Pointer<Uint8> data, int len, Pointer<Uint8> hash, Pointer<IntPtr> hsize, Pointer<NativeType> alg, Pointer<NativeType> engine)
+>('EVP_Digest');
+
+final EVP_MD_size = libcrypto.lookupFunction<
+  IntPtr Function(Pointer<NativeType> ctx),
+  int Function(Pointer<NativeType> ctx)
+>('EVP_MD_size');
+

lib/src/utils/crypto/js.dart

@@ -9,6 +9,8 @@ import 'subtle.dart' as subtle;
 abstract class Hash {
   Hash._(this.name);
   String name;
+
+  Future<Uint8List> call(Uint8List input) async => Uint8List.view(await digest(name, input));
 }
 
 final Hash sha1 = _Sha1();

lib/src/utils/crypto/native.dart

@@ -7,6 +7,19 @@ import 'ffi.dart';
 abstract class Hash {
   Hash._(this.ptr);
   Pointer<NativeType> ptr;
+
+  Uint8List call(Uint8List data) {
+    final outSize = EVP_MD_size(ptr);
+    final mem = malloc.call<Uint8>(outSize + data.length);
+    final dataMem = mem.elementAt(outSize);
+    try {
+      dataMem.asTypedList(data.length).setAll(0, data);
+      EVP_Digest(dataMem, data.length, mem, nullptr, ptr, nullptr);
+      return Uint8List.fromList(mem.asTypedList(outSize));
+    } finally {
+      malloc.free(mem);
+    }
+  }
 }
 
 final Hash sha1 = _Sha1();

lib/src/utils/crypto/subtle.dart

@@ -75,3 +75,10 @@ external dynamic _deriveBits(dynamic algorithm, CryptoKey baseKey, int length);
 Future<ByteBuffer> deriveBits(dynamic algorithm, CryptoKey baseKey, int length) {
   return promiseToFuture(_deriveBits(algorithm, baseKey, length));
 }
+
+@JS('crypto.subtle.digest')
+external dynamic _digest(String algorithm, Uint8List data);
+
+Future<ByteBuffer> digest(String algorithm, Uint8List data) {
+  return promiseToFuture(_digest(algorithm, data));
+}

lib/src/utils/matrix_file.dart

@@ -20,7 +20,7 @@
 
 import 'dart:typed_data';
 
-import 'package:matrix_file_e2ee/matrix_file_e2ee.dart';
+import 'crypto/encrypted_file.dart';
 import 'package:mime/mime.dart';
 
 import '../../famedlysdk.dart';

pubspec.yaml

@@ -18,10 +18,6 @@ dependencies:
   crypto: ^3.0.0
   base58check: ^2.0.0
   olm: ^2.0.0
-  matrix_file_e2ee:
-    git:
-      url: https://gitlab.com/famedly/libraries/matrix_file_e2ee.git
-      ref: nullsafety
   isolate: ^2.0.3
   logger: ^1.0.0
   matrix_api_lite: ^0.2.4