feature/dht-create (#55)

* moved from old fork

* updated create function with algorithm handling

* updated key generation and storage to match web did

* revert key manager changes

packages/web5/lib/src/crypto/crypto.dart

@@ -37,6 +37,17 @@ class Crypto {
     }
   }
 
+  static Uint8List publicKeyToBytes(Jwk publicKey) {
+    switch (publicKey.kty) {
+      case Ed25519.kty:
+        return Ed25519.publicKeyToBytes(publicKey: publicKey);
+      case Secp256k1.kty:
+        return Secp256k1.publicKeyToBytes(publicKey: publicKey);
+      default:
+        throw Exception('unsupported kty: ${publicKey.kty}');
+    }
+  }
+
   static Future<Uint8List> sign(Jwk privateKeyJwk, Uint8List payload) {
     switch (privateKeyJwk.kty) {
       case Ecdsa.kty:

packages/web5/lib/src/crypto/ed25519.dart

@@ -1,3 +1,4 @@
+import 'dart:convert';
 import 'dart:typed_data';
 
 import 'package:cryptography/cryptography.dart' as crypto;
@@ -51,6 +52,17 @@ class Ed25519 {
     return privateKeyJwk;
   }
 
+  static Uint8List publicKeyToBytes({required Jwk publicKey}) {
+    if (publicKey.x == null) {
+      throw Error();
+    }
+
+    final Uint8List encodedKey = utf8.encode(publicKey.x!);
+    final String base64Url = base64UrlEncode(encodedKey);
+
+    return utf8.encode(base64Url);
+  }
+
   static Future<Uint8List> sign(Jwk privateKey, Uint8List payload) async {
     final privateKeyBytes = Base64Url.decode(privateKey.d!);
 

packages/web5/lib/src/crypto/secp256k1.dart

@@ -1,3 +1,4 @@
+import 'dart:convert';
 import 'dart:math';
 import 'dart:typed_data';
 
@@ -79,6 +80,17 @@ class Secp256k1 {
     return Future.value(privateKeyJwk);
   }
 
+  static Uint8List publicKeyToBytes({required Jwk publicKey}) {
+    if (publicKey.x == null) {
+      throw Error();
+    }
+
+    final Uint8List encodedKey = utf8.encode(publicKey.x!);
+    final String base64Url = base64UrlEncode(encodedKey);
+
+    return utf8.encode(base64Url);
+  }
+
   static Future<Uint8List> sign(Jwk privateKeyJwk, Uint8List payload) {
     final sha256 = SHA256Digest();
 

packages/web5/lib/src/dids/did_core/did_document_metadata.dart

@@ -1,3 +1,5 @@
+import 'package:web5/src/dids/did_dht/registered_did_type.dart';
+
 /// contains metadata about the DID document contained in the didDocument
 /// property. This metadata typically does not change between invocations of
 /// the resolve and resolveRepresentation functions unless the DID document
@@ -51,6 +53,8 @@ class DidDocumentMetadata {
   ///     the scope of the containing DID document.
   final String? canonicalId;
 
+  final List<DidDhtRegisteredDidType>? types;
+
   const DidDocumentMetadata({
     this.created,
     this.updated,
@@ -60,6 +64,7 @@ class DidDocumentMetadata {
     this.nextVersionId,
     this.equivalentId,
     this.canonicalId,
+    this.types,
   });
 
   Map<String, dynamic> toJson() {
@@ -72,6 +77,7 @@ class DidDocumentMetadata {
       'nextVersionId': nextVersionId,
       'equivalentId': equivalentId,
       'canonicalId': canonicalId,
+      'types': types?.map((e) => e.value) ?? [],
     };
 
     json.removeWhere((key, value) => value == null);
@@ -105,6 +111,7 @@ class DidDocumentMetadata {
       nextVersionId,
       equivalentId,
       canonicalId,
+      types,
     );
   }
 }

packages/web5/lib/src/dids/did_dht/did_dht.dart

@@ -1,11 +1,15 @@
 import 'dart:io';
+import 'dart:typed_data';
 
 import 'package:web5/src/crypto.dart';
+import 'package:web5/src/dids/bearer_did.dart';
 import 'package:web5/src/dids/did.dart';
 import 'package:web5/src/dids/did_core.dart';
 import 'package:web5/src/dids/did_dht/dns_packet.dart';
+import 'package:web5/src/dids/did_dht/registered_did_type.dart';
 import 'package:web5/src/dids/did_method_resolver.dart';
 import 'package:web5/src/encoders.dart';
+import 'package:web5/src/encoders/zbase.dart';
 
 final Set<String> txtEntryNames = {'vm', 'auth', 'asm', 'agm', 'inv', 'del'};
 
@@ -14,6 +18,126 @@ class DidDht {
 
   static final resolver = DidMethodResolver(name: methodName, resolve: resolve);
 
+  static Future<BearerDid> create({
+    KeyManager? keyManager,
+    List<String>? alsoKnownAs,
+    List<String>? controllers,
+    String? gatewayUri,
+    bool? publish,
+    List<DidService>? services,
+    List<DidDhtRegisteredDidType>? types,
+    List<DidCreateVerificationMethod>? verificationMethods,
+  }) async {
+    final AlgorithmId idAlgorithm = AlgorithmId.ed25519;
+    keyManager ??= InMemoryKeyManager();
+
+    // Generate random key material for the Identity Key.
+    final String keyAlias = await keyManager.generatePrivateKey(idAlgorithm);
+    final Jwk identityKey = await keyManager.getPublicKey(keyAlias);
+
+    final String didUri = identityKeyToIdentifier(identityKey: identityKey);
+    final DidDocument doc = DidDocument(
+      id: didUri,
+      alsoKnownAs: alsoKnownAs,
+      controller: controllers ?? didUri,
+    );
+
+    // If the given verification methods do not contain an Identity Key, add one.
+    final List<DidCreateVerificationMethod> methodsToAdd =
+        verificationMethods ?? [];
+
+    final Iterable<DidCreateVerificationMethod> identityMethods =
+        methodsToAdd.where(
+      (vm) => vm.id?.split('#').last == '0',
+    );
+
+    if (identityMethods.isEmpty) {
+      methodsToAdd.add(
+        DidCreateVerificationMethod(
+          algorithm: AlgorithmId.ed25519,
+          id: '0',
+          type: 'JsonWebKey',
+          controller: didUri,
+          purposes: [
+            VerificationPurpose.authentication,
+            VerificationPurpose.assertionMethod,
+            VerificationPurpose.capabilityDelegation,
+            VerificationPurpose.capabilityInvocation,
+          ],
+        ),
+      );
+    }
+
+    // Generate random key material for the Identity Key and any additional verification methods.
+    // Add verification methods to the DID document.
+    for (final DidCreateVerificationMethod vm in methodsToAdd) {
+      // Generate a random key for the verification method, or if its the Identity Key's
+      // verification method (`id` is 0) use the key previously generated.
+      late Jwk publicKey;
+
+      if (vm.id?.split('#').last == '0') {
+        publicKey = identityKey;
+      } else {
+        String alias = await keyManager.generatePrivateKey(vm.algorithm);
+        publicKey = await keyManager.getPublicKey(alias);
+      }
+
+      // Use the given ID, the key's ID, or the key's thumbprint as the verification method ID.
+      String methodId = vm.id ?? publicKey.kid ?? publicKey.computeThumbprint();
+      methodId = '$didUri#${methodId.split('#').last}';
+
+      doc.addVerificationMethod(
+        DidVerificationMethod(
+          id: methodId,
+          type: vm.type,
+          controller: vm.controller,
+          publicKeyJwk: publicKey,
+        ),
+      );
+
+      for (final VerificationPurpose purpose in vm.purposes) {
+        doc.addVerificationPurpose(purpose, methodId);
+      }
+    }
+
+    for (final DidService service in (services ?? [])) {
+      doc.addService(service);
+    }
+
+    final BearerDid did = BearerDid(
+      uri: didUri,
+      keyManager: keyManager,
+      document: doc,
+      metadata: DidDocumentMetadata(
+        types: types,
+      ),
+    );
+
+    if (publish ?? true) {
+      DidDht.publish(did: did);
+    }
+
+    return did;
+  }
+
+  static String identityKeyToIdentifier({
+    required Jwk identityKey,
+  }) {
+    // Convert the key from JWK format to a byte array.
+    final Uint8List publicKeyBytes = Crypto.publicKeyToBytes(identityKey);
+
+    final String identifier = ZBase32.encode(publicKeyBytes);
+    return 'did:${DidDht.methodName}:$identifier';
+  }
+
+  static Future<void> publish({
+    required BearerDid did,
+    String? gatewayUri,
+  }) async {
+    // TODO: Finish publish method
+    // final DnsPacket dnsPacket = DnsPacket.fromDid(did);
+  }
+
   static Future<DidResolutionResult> resolve(
     Did did, {
     String relayUrl = 'https://diddht.tbddev.org',

packages/web5/lib/src/dids/did_dht/dns_packet/answer.dart

@@ -8,6 +8,22 @@ import 'package:web5/src/dids/did_dht/dns_packet/consts.dart';
 import 'package:web5/src/dids/did_dht/dns_packet/opt_data.dart';
 import 'package:web5/src/dids/did_dht/dns_packet/txt_data.dart';
 
+class BaseAnswer<D> {
+  BaseAnswer({
+    required this.type,
+    required this.name,
+    this.ttl,
+    this.classType,
+    required this.data,
+  });
+
+  DnsType type;
+  String name;
+  int? ttl;
+  String? classType;
+  D data;
+}
+
 /// Represents an answer section in a DNS packet.
 class DnsAnswer {
   /// The domain name to which this resource record pertains.

packages/web5/lib/src/dids/did_dht/dns_packet/header.dart

@@ -4,20 +4,49 @@ import 'package:web5/src/dids/did_dht/dns_packet/opcode.dart';
 import 'package:web5/src/dids/did_dht/dns_packet/rcode.dart';
 
 class DnsHeader {
+  /// Identifier assigned by the program that generates the query.
   int id;
+
+  /// Whether this message is a query (0), or a response (1)
   bool qr;
+
+  /// Specifies kind of query in this message.
   DnsOpCode opcode;
-  bool aa;
+
+  /// Specifies that the responding name server is an authority for the domain name in question section.
+  bool? aa;
+
+  /// Specifies whether the message was truncated.
   bool tc;
+
+  /// Directs the name server to pursue the query recursively
   bool rd;
-  bool ra;
+
+  /// Set or cleared in a response, and denotes whether recursive query support is available in the name server
+  bool? ra;
+
+  /// Reserved for future use, always set to 0.
   bool z;
-  bool ad;
-  bool cd;
-  DnsRCode rcode;
+
+  /// TODO: Find documentation for this field
+  bool? ad;
+
+  /// TODO: Find documentation for this field
+  bool? cd;
+
+  /// Response code
+  DnsRCode? rcode;
+
+  /// Number of entries in the question section.
   int qdcount;
+
+  /// Number of resource records in the answer section.
   int ancount;
+
+  /// Number of name server resource records in the authority records section.
   int nscount;
+
+  /// Number of resource records in the additional records section.
   int arcount;
 
   get numQuestions => qdcount;
@@ -31,14 +60,14 @@ class DnsHeader {
     required this.id,
     required this.qr,
     required this.opcode,
-    required this.aa,
+    this.aa,
     required this.tc,
     required this.rd,
-    required this.ra,
-    required this.z,
-    required this.ad,
-    required this.cd,
-    required this.rcode,
+    this.ra,
+    this.z = false,
+    this.ad,
+    this.cd,
+    this.rcode,
     required this.qdcount,
     required this.ancount,
     required this.nscount,