1.4.0

.gitignore

@@ -1,6 +1,9 @@
 # Files and directories created by pub.
 .dart_tool/
 .packages
+*.swp
+x
+tags
 
 # Conventional directory for build outputs.
 build/

README.md

@@ -16,8 +16,15 @@ flutter pub add nostr
 ## [NIPS](https://github.com/nostr-protocol/nips)
 - [x] [NIP 01 Basic protocol flow description](https://github.com/nostr-protocol/nips/blob/master/01.md)
 - [x] [NIP 02 Contact List and Petnames](https://github.com/nostr-protocol/nips/blob/master/02.md)
+- [x] [NIP 04 Encrypted Direct Message](https://github.com/nostr-protocol/nips/blob/master/04.md)
+- [x] [NIP 05 Mapping Nostr keys to DNS-based internet identifiers](https://github.com/nostr-protocol/nips/blob/master/05.md)
+- [x] [NIP 10 Conventions for clients' use of e and p tags in text events](https://github.com/nostr-protocol/nips/blob/master/10.md)
 - [x] [NIP 15 End of Stored Events Notice](https://github.com/nostr-protocol/nips/blob/master/15.md)
+- [x] [NIP 19 bech32-encoded entities](https://github.com/nostr-protocol/nips/blob/master/19.md)
 - [x] [NIP 20 Command Results](https://github.com/nostr-protocol/nips/blob/master/20.md)
+- [x] [NIP 28 Public Chat](https://github.com/nostr-protocol/nips/blob/master/28.md)
+- [x] [NIP 51 Lists](https://github.com/nostr-protocol/nips/blob/master/51.md)
+
 
 ## Usage
 ### Events messages

example/message_example.dart

@@ -2,7 +2,7 @@ import 'package:nostr/nostr.dart';
 
 void main() async {
  var eventPayload =
- '["EVENT","3979053091133091",{"id":"a60679692533b308f1d862c2a5ca5c08a304e5157b1df5cde0ff0454b9920605","pubkey":"7c579328cf9028a4548d5117afa4f8448fb510ca9023f576b7bc90fc5be6ce7e","created_at":1674405882,"kind":1,"tags":[],"content":"GM gm gm! Currently bathing my brain in coffee ☕️ hahaha. How many other nostrinos love coffee? 🤪🤙","sig":"10262aa6a83e0b744cda2097f06f7354357512b82846f6ef23ef7d997136b64815c343b613a0635a27da7e628c96ac2475f66dd72513c1fb8ce6560824eb25b8"}]';
+ '["EVENT","5ce1758166673a70e391303fb7cfeb0f5d47ec38a9342a27858950d13424d59b",{"content":"No quotes from the Bible? My global feed is full of religious nutcases","created_at":1685026912,"id":"e695c81fa5099b9f3ef0d868d8143eae481954114681bbe4432b50e44e199927","kind":1,"pubkey":"ab4103fc8cd4e1d8d31a99d079ed8293bdc26b11ec1ec61d95c13e43d7e048ff","sig":"0d17d6197ad12ab5ad77eb51231ae12c2ce1e639218bb6e3a01cce78aa092f3e77fb1f914b690675a425dcfd5b4dfa7be72c2cb608568798361781d75e354b32","tags":[["e","7804acd35bb9727d0374545a99bb4f30f901289aebaf3cf330dda28c235cd7ad"],["p","1bc70a0148b3f316da33fe3c89f23e3e71ac4ff998027ec712b905cd24f6a411"]]}]';
  var event = Message.deserialize(eventPayload);
  assert(event.type == "EVENT");
  assert(event.message.id ==

lib/nostr.dart

@@ -11,3 +11,10 @@ export 'src/close.dart';
 export 'src/message.dart';
 export 'src/utils.dart';
 export 'src/nips/nip_002.dart';
+export 'src/nips/nip_004.dart';
+export 'src/nips/nip_005.dart';
+export 'src/nips/nip_010.dart';
+export 'src/nips/nip_019.dart';
+export 'src/nips/nip_020.dart';
+export 'src/nips/nip_028.dart';
+export 'src/nips/nip_051.dart';

lib/src/close.dart

@@ -17,7 +17,7 @@ class Close {
  /// Deserialize a nostr close message
  /// - ["CLOSE", subscription_id]
  Close.deserialize(input) {
- assert(input.length == 2);
+ if (input.length != 2) throw 'Invalid length for CLOSE message';
  subscriptionId = input[1];
  }
 }

lib/src/crypto/kepler.dart

@@ -0,0 +1,63 @@
+// credit: https://github.com/tjcampanella/kepler/blob/master/lib/src/kepler.dart
+
+import 'package:convert/convert.dart';
+import 'dart:typed_data';
+import 'package:pointycastle/export.dart';
+import 'operator.dart';
+
+class Kepler {
+ /// return a Bytes data secret
+ static List<List<int>> byteSecret(String privateString, String publicString) {
+ final secret = rawSecret(privateString, publicString);
+ assert(secret.x != null && secret.y != null);
+ final xs = secret.x!.toBigInteger()!.toRadixString(16);
+ final ys = secret.y!.toBigInteger()!.toRadixString(16);
+ final hexX = leftPadding(xs, 64);
+ final hexY = leftPadding(ys, 64);
+ final secretBytes = Uint8List.fromList(hex.decode('$hexX$hexY'));
+ return [secretBytes.sublist(0, 32), secretBytes.sublist(32, 40)];
+ }
+
+ /// return a ECPoint data secret
+ static ECPoint rawSecret(String privateString, String publicString) {
+ final privateKey = loadPrivateKey(privateString);
+ final publicKey = loadPublicKey(publicString);
+ assert(privateKey.d != null && publicKey.Q != null);
+ return scalarMultiple(privateKey.d!, publicKey.Q!);
+ }
+
+ static String leftPadding(String s, int width) {
+ const paddingData = '000000000000000';
+ final paddingWidth = width - s.length;
+ if (paddingWidth < 1) {
+ return s;
+ }
+ return "${paddingData.substring(0, paddingWidth)}$s";
+ }
+
+ /// return a privateKey from hex string
+ static ECPrivateKey loadPrivateKey(String storedkey) {
+ final d = BigInt.parse(storedkey, radix: 16);
+ final param = ECCurve_secp256k1();
+ return ECPrivateKey(d, param);
+ }
+
+ /// return a publicKey from hex string
+ static ECPublicKey loadPublicKey(String storedkey) {
+ final param = ECCurve_secp256k1();
+ if (storedkey.length < 120) {
+ List<int> codeList = [];
+ for (var idx = 0; idx < storedkey.length - 1; idx += 2) {
+ final hexStr = storedkey.substring(idx, idx + 2);
+ codeList.add(int.parse(hexStr, radix: 16));
+ }
+ final Q = param.curve.decodePoint(codeList);
+ return ECPublicKey(Q, param);
+ } else {
+ final x = BigInt.parse(storedkey.substring(0, 64), radix: 16);
+ final y = BigInt.parse(storedkey.substring(64), radix: 16);
+ final Q = param.curve.createPoint(x, y);
+ return ECPublicKey(Q, param);
+ }
+ }
+}

lib/src/crypto/nip_004.dart

@@ -0,0 +1,58 @@
+import 'dart:convert';
+import 'dart:typed_data';
+import 'package:nostr/nostr.dart';
+import 'package:nostr/src/crypto/kepler.dart';
+import 'package:pointycastle/export.dart';
+
+/// NIP4 cipher
+String nip4cipher(
+ String privkey,
+ String pubkey,
+ String payload,
+ bool cipher, {
+ String? nonce,
+}) {
+ // if cipher=false –> decipher –> nonce needed
+ if (!cipher && nonce == null) throw Exception("missing nonce");
+
+ // init variables
+ Uint8List input, output, iv;
+ if (!cipher && nonce != null) {
+ input = base64.decode(payload);
+ output = Uint8List(input.length);
+ iv = base64.decode(nonce);
+ } else {
+ input = Utf8Encoder().convert(payload);
+ output = Uint8List(input.length + 16);
+ iv = Uint8List.fromList(generateRandomBytes(16));
+ }
+
+ // params
+ List<List<int>> keplerSecret = Kepler.byteSecret(privkey, pubkey);
+ var key = Uint8List.fromList(keplerSecret[0]);
+ var params = PaddedBlockCipherParameters(
+ ParametersWithIV(KeyParameter(key), iv),
+ null,
+ );
+ var algo = PaddedBlockCipherImpl(
+ PKCS7Padding(),
+ CBCBlockCipher(AESEngine()),
+ );
+
+ // processing
+ algo.init(cipher, params);
+ var offset = 0;
+ while (offset < input.length - 16) {
+ offset += algo.processBlock(input, offset, output, offset);
+ }
+ offset += algo.doFinal(input, offset, output, offset);
+ Uint8List result = output.sublist(0, offset);
+
+ if (cipher) {
+ String stringIv = base64.encode(iv);
+ String plaintext = base64.encode(result);
+ return "$plaintext?iv=$stringIv";
+ } else {
+ return Utf8Decoder().convert(result);
+ }
+}

lib/src/crypto/operator.dart

@@ -0,0 +1,113 @@
+// credit: https://github.com/tjcampanella/kepler/blob/master/lib/src/operator.dart
+
+import 'package:pointycastle/export.dart';
+
+BigInt theP = BigInt.parse(
+ "fffffffffffffffffffffffffffffffffffffffffffffffffffffffefffffc2f",
+ radix: 16);
+BigInt theN = BigInt.parse(
+ "fffffffffffffffffffffffffffffffebaaedce6af48a03bbfd25e8cd0364141",
+ radix: 16);
+
+bool isOnCurve(ECPoint point) {
+ assert(point.x != null &&
+ point.y != null &&
+ point.curve.a != null &&
+ point.curve.b != null);
+ final x = point.x!.toBigInteger();
+ final y = point.y!.toBigInteger();
+ final rs = (y! * y -
+ x! * x * x -
+ point.curve.a!.toBigInteger()! * x -
+ point.curve.b!.toBigInteger()!) %
+ theP;
+ return rs == BigInt.from(0);
+}
+
+BigInt inverseMod(BigInt k, BigInt p) {
+ if (k.compareTo(BigInt.zero) == 0) {
+ throw Exception("Cannot Divide By 0");
+ }
+ if (k < BigInt.from(0)) {
+ return p - inverseMod(-k, p);
+ }
+ var s = [BigInt.from(0), BigInt.from(1), BigInt.from(1)];
+ var t = [BigInt.from(1), BigInt.from(0), BigInt.from(0)];
+ var r = [p, k, k];
+ while (r[0] != BigInt.from(0)) {
+ var quotient = r[2] ~/ r[0];
+ r[1] = r[2] - quotient * r[0];
+ r[2] = r[0];
+ r[0] = r[1];
+ s[1] = s[2] - quotient * s[0];
+ s[2] = s[0];
+ s[0] = s[1];
+ t[1] = t[2] - quotient * t[0];
+ t[2] = t[0];
+ t[0] = t[1];
+ }
+ final gcd = r[2];
+ final x = s[2];
+ // final y = t[2];
+ assert(gcd == BigInt.from(1));
+ assert((k * x) % p == BigInt.from(1));
+ return x % p;
+}
+
+ECPoint pointNeg(ECPoint point) {
+ assert(isOnCurve(point));
+ assert(point.x != null || point.y != null);
+ final x = point.x!.toBigInteger();
+ final y = point.y!.toBigInteger();
+ final result = point.curve.createPoint(x!, -y! % theP);
+ assert(isOnCurve(result));
+ return result;
+}
+
+ECPoint pointAdd(ECPoint? point1, ECPoint? point2) {
+ if (point1 == null) {
+ return point2!;
+ }
+ if (point2 == null) {
+ return point1;
+ }
+ assert(isOnCurve(point1));
+ assert(isOnCurve(point2));
+ final x1 = point1.x!.toBigInteger();
+ final y1 = point1.y!.toBigInteger();
+ final x2 = point2.x!.toBigInteger();
+ final y2 = point2.y!.toBigInteger();
+
+ BigInt m;
+ if (x1 == x2) {
+ m = (BigInt.from(3) * x1! * x1 + point1.curve.a!.toBigInteger()!) *
+ inverseMod(BigInt.from(2) * y1!, theP);
+ } else {
+ m = (y1! - y2!) * inverseMod(x1! - x2!, theP);
+ }
+ final x3 = m * m - x1 - x2!;
+ final y3 = y1 + m * (x3 - x1);
+ ECPoint result = point1.curve.createPoint(x3 % theP, -y3 % theP);
+ assert(isOnCurve(result));
+ return result;
+}
+
+ECPoint scalarMultiple(BigInt k, ECPoint point) {
+ assert(isOnCurve(point));
+ assert((k % theN).compareTo(BigInt.zero) != 0);
+ assert(point.x != null && point.y != null);
+ if (k < BigInt.from(0)) {
+ return scalarMultiple(-k, pointNeg(point));
+ }
+ ECPoint? result;
+ ECPoint addend = point;
+ while (k > BigInt.from(0)) {
+ if (k & BigInt.from(1) > BigInt.from(0)) {
+ result = pointAdd(result, addend);
+ }
+ addend = pointAdd(addend, addend);
+ k >>= 1;
+ }
+ assert(isOnCurve(result!));
+ return result!;
+}

lib/src/event.dart

@@ -1,6 +1,7 @@
 import 'dart:convert';
+import 'dart:typed_data';
 import 'package:convert/convert.dart';
-import 'package:crypto/crypto.dart';
+import 'package:pointycastle/export.dart';
 import 'package:bip340/bip340.dart' as bip340;
 import 'package:nostr/src/utils.dart';
 
@@ -85,7 +86,7 @@ class Event {
  bool verify = true,
  }) {
  pubkey = pubkey.toLowerCase();
- if (verify) assert(isValid() == true);
+ if (verify && isValid() == false) throw 'Invalid event';
  }
 
  /// Partial constructor, you have to fill the fields yourself
@@ -127,27 +128,26 @@ class Event {
  );
  }
 
- /// Instantiate Event object from the minimum available data
+ /// Instantiate Event object from the minimum needed data
  ///
  /// ```dart
  ///Event event = Event.from(
  /// kind: 1,
- /// tags: [],
  /// content: "",
  /// privkey:
  /// "5ee1c8000ab28edd64d74a7d951ac2dd559814887b1b9e1ac7c5f89e96125c12",
  ///);
  ///```
  factory Event.from({
- int createdAt = 0,
+ int? createdAt,
  required int kind,
- required List<List<String>> tags,
+ List<List<String>> tags = const [],
  required String content,
  required String privkey,
  String? subscriptionId,
  bool verify = false,
  }) {
- if (createdAt == 0) createdAt = currentUnixTimestampSeconds();
+ createdAt ??= currentUnixTimestampSeconds();
  final pubkey = bip340.getPublicKey(privkey).toLowerCase();
 
  final id = _processEventId(
@@ -253,7 +253,7 @@ class Event {
  throw Exception('invalid input');
  }
 
- var tags = (json['tags'] as List<dynamic>)
+ List<List<String>> tags = (json['tags'] as List<dynamic>)
  .map((e) => (e as List<dynamic>).map((e) => e as String).toList())
  .toList();
 
@@ -302,7 +302,8 @@ class Event {
  ) {
  List data = [0, pubkey.toLowerCase(), createdAt, kind, tags, content];
  String serializedEvent = json.encode(data);
- List<int> hash = sha256.convert(utf8.encode(serializedEvent)).bytes;
+ Uint8List hash = SHA256Digest()
+ .process(Uint8List.fromList(utf8.encode(serializedEvent)));
  return hex.encode(hash);
  }
 

lib/src/message.dart

@@ -11,12 +11,19 @@ class Message {
  Message.deserialize(String payload) {
  dynamic data = jsonDecode(payload);
  var messages = ["EVENT", "REQ", "CLOSE", "NOTICE", "EOSE", "OK", "AUTH"];
- assert(messages.contains(data[0]), "Unsupported payload (or NIP)");
+ if (messages.contains(data[0]) == false) {
+ throw 'Unsupported payload (or NIP)';
+ }
 
  type = data[0];
  switch (type) {
  case "EVENT":
  message = Event.deserialize(data);
+ // ignore: deprecated_member_use_from_same_package
+ if (message.kind == 4) message = EncryptedDirectMessage(message);
+ break;
+ case "OK":
+ message = Nip20.deserialize(data);
  break;
  case "REQ":
  message = Request.deserialize(data);