fix(mobile): honor authenticated owner policy in agent candidates

mobile/lib/features/channels/channel_management_provider.dart

@@ -296,17 +296,7 @@ List<String> relayMemberPubkeysFromEvents(List<NostrEvent> events) {
 /// Converts kind:0 events into a deduplicated, alphabetized people directory.
 @visibleForTesting
 List<DirectoryUser> directoryUsersFromProfileEvents(List<NostrEvent> events) {
-  final latestByPubkey = <String, NostrEvent>{};
-  for (final event in events) {
-    if (event.kind != 0) {
-      continue;
-    }
-    final pubkey = event.pubkey.toLowerCase();
-    final current = latestByPubkey[pubkey];
-    if (current == null || event.createdAt > current.createdAt) {
-      latestByPubkey[pubkey] = event;
-    }
-  }
+  final latestByPubkey = latestProfileEvents(events);
 
   return [
     for (final event in latestByPubkey.values)
@@ -316,7 +306,7 @@ List<DirectoryUser> directoryUsersFromProfileEvents(List<NostrEvent> events) {
           displayName: profile.displayName,
           avatarUrl: profile.avatarUrl,
           nip05Handle: profile.nip05,
-          isAgent: verifiedOaOwnerPubkey(event.tags, event.pubkey) != null,
+          isAgent: verifiedOaOwnerPubkey(event) != null,
         ),
   ]..sort((a, b) {
     final labelComparison = a.label.toLowerCase().compareTo(
@@ -373,29 +363,14 @@ final relayDirectoryUsersProvider =
         NostrFilters.profilesBatch(memberPubkeys),
       ]);
       final profilesByPubkey = {
-        for (final event in profileEvents)
-          event.pubkey.toLowerCase(): ProfileData.fromEvent(event),
+        for (final user in directoryUsersFromProfileEvents(profileEvents))
+          user.pubkey: user,
       };
       users =
           [
             for (final pubkey in memberPubkeys)
               if (profilesByPubkey[pubkey] case final profile?)
-                DirectoryUser(
-                  pubkey: pubkey,
-                  displayName: profile.displayName,
-                  avatarUrl: profile.avatarUrl,
-                  nip05Handle: profile.nip05,
-                  isAgent:
-                      verifiedOaOwnerPubkey(
-                        profileEvents
-                            .firstWhere(
-                              (event) => event.pubkey.toLowerCase() == pubkey,
-                            )
-                            .tags,
-                        pubkey,
-                      ) !=
-                      null,
-                )
+                profile
               else
                 DirectoryUser(pubkey: pubkey),
           ]..sort((a, b) {

mobile/lib/features/channels/mentions/mention_candidates.dart

@@ -12,6 +12,11 @@ bool agentIsSharedWithUser(
   Set<String> sharedChannelIds,
   String? currentPubkey,
 ) {
+  if (currentPubkey != null &&
+      agent.ownerPubkey == currentPubkey.toLowerCase() &&
+      const ['owner-only', 'allowlist', 'anyone'].contains(agent.respondTo)) {
+    return true;
+  }
   if (agent.respondTo == 'allowlist' && currentPubkey != null) {
     return agent.respondToAllowlist.contains(currentPubkey.toLowerCase());
   }
@@ -62,6 +67,11 @@ List<MentionCandidate> buildMentionCandidates({
     final profile = userCache[pk];
     final ownerPubkey = ownerByAgentPubkey[pk] ?? profile?.ownerPubkey;
     final isAgent = member.isBot || ownerPubkey != null;
+    final policy = relayAgents.where((agent) => agent.pubkey == pk).firstOrNull;
+    if (policy?.ownerPubkey != null &&
+        !agentIsSharedWithUser(policy!, sharedChannelIds, currentPubkey)) {
+      continue;
+    }
     candidates.add(
       MentionCandidate(
         pubkey: pk,
@@ -121,6 +131,12 @@ List<MentionCandidate> buildMentionCandidates({
       // verified NIP-OA owner) or shared via the relay agent directory.
       final ownedByCurrentUser =
           currentLower != null && ownerPubkey?.toLowerCase() == currentLower;
+      final policy = relayAgents
+          .where((agent) => agent.pubkey == pk)
+          .firstOrNull;
+      if (policy?.ownerPubkey != null && !sharedAgentPubkeys.contains(pk)) {
+        continue;
+      }
       if (!ownedByCurrentUser && !sharedAgentPubkeys.contains(pk)) {
         continue;
       }

mobile/lib/features/channels/mentions/mention_candidates_provider.dart

@@ -38,16 +38,7 @@ final mentionUserSearchProvider = FutureProvider.autoDispose
       // Keep only the latest kind:0 event per pubkey (the bridge does not
       // honor the `kinds` filter under search, and may return several
       // profile revisions — mirrors desktop's `list_user_search_results`).
-      final latestByPubkey = <String, NostrEvent>{};
-      for (final event in events) {
-        if (event.kind != 0) continue;
-        final pk = event.pubkey.toLowerCase();
-        final current = latestByPubkey[pk];
-        if (current == null || event.createdAt > current.createdAt) {
-          latestByPubkey[pk] = event;
-        }
-      }
-
+      final latestByPubkey = latestProfileEvents(events);
       return [
         for (final event in latestByPubkey.values) _profileFromEvent(event),
       ];
@@ -61,7 +52,7 @@ UserProfile _profileFromEvent(NostrEvent event) {
     avatarUrl: data.avatarUrl,
     about: data.about,
     nip05Handle: data.nip05,
-    ownerPubkey: verifiedOaOwnerPubkey(event.tags, event.pubkey),
+    ownerPubkey: verifiedOaOwnerPubkey(event),
   );
 }
 

mobile/lib/features/profile/profile_provider.dart

@@ -116,7 +116,7 @@ class ProfileNotifier extends AsyncNotifier<UserProfile?> {
       avatarUrl: data.avatarUrl,
       about: data.about,
       nip05Handle: data.nip05,
-      ownerPubkey: verifiedOaOwnerPubkey(latest.tags, data.pubkey),
+      ownerPubkey: verifiedOaOwnerPubkey(latest),
     );
     _requireCurrentWriteContext(context);
     _metadata = metadata;
@@ -233,7 +233,7 @@ class ProfileNotifier extends AsyncNotifier<UserProfile?> {
       avatarUrl: _metadata['picture'] as String?,
       about: _metadata['about'] as String?,
       nip05Handle: _metadata['nip05'] as String?,
-      ownerPubkey: verifiedOaOwnerPubkey(submittedEvent.tags, pubkey),
+      ownerPubkey: verifiedOaOwnerPubkey(submittedEvent),
     );
     state = AsyncData(profile);
     ref.read(userCacheProvider.notifier).put(profile);

mobile/lib/shared/crypto/nip_oa.dart

@@ -4,6 +4,9 @@ import 'dart:typed_data';
 import 'package:nostr/nostr.dart' as nostr;
 import 'package:pointycastle/digests/sha256.dart';
 
+import '../relay/nostr_models.dart';
+import 'signed_event.dart';
+
 /// NIP-OA (Owner Attestation) — verify the `auth` tag on a kind:0 profile
 /// that proves an owner key authorized an agent key.
 ///
@@ -15,48 +18,60 @@ import 'package:pointycastle/digests/sha256.dart';
 /// verified against the profile event author, so a forged or stale marker
 /// cannot turn a person into an agent.
 ///
-/// Returns the owner pubkey (lowercase hex) for the first valid auth tag,
-/// or null if none verifies.
-String? verifiedOaOwnerPubkey(List<List<String>> tags, String agentPubkey) {
-  final agent = agentPubkey.toLowerCase();
-
-  for (final tag in tags) {
-    if (tag.length != 4 || tag[0] != 'auth') continue;
-
-    final owner = tag[1].toLowerCase();
-    final conditions = tag[2];
-    final sig = tag[3];
-
-    // Self-attestation is meaningless and rejected.
-    if (owner == agent) continue;
-    if (owner.length != 64 || sig.length != 128) continue;
-    if (!_validConditions(conditions)) continue;
-
-    final preimage = utf8.encode('nostr:agent-auth:$agent:$conditions');
-    final digest = SHA256Digest().process(Uint8List.fromList(preimage));
-    final message = digest
-        .map((b) => b.toRadixString(16).padLeft(2, '0'))
-        .join();
+/// Returns the owner only when the signed profile has exactly one valid auth
+/// tag whose conditions apply to that event (not to the verifier's clock).
+String? verifiedOaOwnerPubkey(NostrEvent event) {
+  if (event.kind != 0) return null;
+  final tags = event.tags.where((tag) => tag.isNotEmpty && tag[0] == 'auth');
+  if (tags.length != 1) return null;
+  final tag = tags.single;
+  if (tag.length != 4) return null;
+  final owner = tag[1];
+  final conditions = tag[2];
+  final sig = tag[3];
+  if (owner == event.pubkey ||
+      !RegExp(r'^[0-9a-f]{64}$').hasMatch(owner) ||
+      !RegExp(r'^[0-9a-f]{128}$').hasMatch(sig) ||
+      !_validConditions(conditions, event) ||
+      !verifySignedEvent(event)) {
+    return null;
+  }
+  final preimage = utf8.encode('nostr:agent-auth:${event.pubkey}:$conditions');
+  final digest = SHA256Digest().process(Uint8List.fromList(preimage));
+  final message = digest.map((b) => b.toRadixString(16).padLeft(2, '0')).join();
+  try {
+    return nostr.Schnorr.verify(
+          publicKey: owner,
+          message: message,
+          signature: sig,
+        )
+        ? owner
+        : null;
+  } catch (_) {
+    return null;
+  }
+}
 
-    try {
-      if (nostr.Schnorr.verify(
-        publicKey: owner,
-        message: message,
-        signature: sig,
-      )) {
-        return owner;
-      }
-    } catch (_) {
-      // Malformed hex — treat as an invalid tag.
+/// Select the latest profile before checking ownership, including revocations.
+/// NIP-01 ties choose the lowest event id, independent of response order.
+Map<String, NostrEvent> latestProfileEvents(Iterable<NostrEvent> events) {
+  final latest = <String, NostrEvent>{};
+  for (final event in events.where((event) => event.kind == 0)) {
+    final key = event.pubkey.toLowerCase();
+    final previous = latest[key];
+    if (previous == null ||
+        event.createdAt > previous.createdAt ||
+        (event.createdAt == previous.createdAt &&
+            event.id.compareTo(previous.id) < 0)) {
+      latest[key] = event;
     }
   }
-
-  return null;
+  return latest;
 }
 
 /// Validate the NIP-OA `conditions` string: empty, or `&`-joined clauses of
 /// `kind=<n>`, `created_at<<n>`, or `created_at><n>` with canonical decimals.
-bool _validConditions(String conditions) {
+bool _validConditions(String conditions, NostrEvent event) {
   if (conditions.isEmpty) return true;
   if (conditions.contains(RegExp(r'\s'))) return false;
 
@@ -67,7 +82,15 @@ bool _validConditions(String conditions) {
     if (match == null) return false;
     final value = int.tryParse(match.group(1)!);
     if (value == null || value > 4294967295) return false;
-    if (clause.startsWith('kind=') && value > 65535) return false;
+    if (clause.startsWith('kind=') && (value > 65535 || value != event.kind)) {
+      return false;
+    }
+    if (clause.startsWith('created_at<') && event.createdAt >= value) {
+      return false;
+    }
+    if (clause.startsWith('created_at>') && event.createdAt <= value) {
+      return false;
+    }
   }
 
   return true;

mobile/lib/shared/crypto/signed_event.dart

@@ -0,0 +1,27 @@
+import 'package:nostr/nostr.dart' as nostr;
+
+import '../relay/nostr_models.dart';
+
+/// Verify the canonical event id and author's signature without a wall-clock
+/// freshness restriction. Authority readers apply their own kind/signer scope.
+bool verifySignedEvent(NostrEvent event) {
+  if (!RegExp(r'^[0-9a-f]{64}$').hasMatch(event.pubkey) ||
+      !RegExp(r'^[0-9a-f]{64}$').hasMatch(event.id) ||
+      !RegExp(r'^[0-9a-f]{128}$').hasMatch(event.sig) ||
+      event.createdAt < 0 ||
+      event.kind < 0 ||
+      event.kind > 65535) {
+    return false;
+  }
+  try {
+    final signed = nostr.Event.fromMap(event.toJson(), verify: false);
+    return signed.getEventId() == event.id &&
+        nostr.Schnorr.verify(
+          publicKey: event.pubkey,
+          message: event.id,
+          signature: event.sig,
+        );
+  } catch (_) {
+    return false;
+  }
+}

mobile/lib/shared/mentions/agent_identity_provider.dart

@@ -5,8 +5,11 @@ import 'package:flutter/foundation.dart';
 import 'package:hooks_riverpod/hooks_riverpod.dart';
 
 import '../../shared/crypto/nip_oa.dart';
+import '../../shared/crypto/signed_event.dart';
 import '../../shared/relay/relay.dart';
 
+part 'agent_policy.dart';
+
 /// A relay agent parsed from its kind:10100 agent-profile event.
 ///
 /// Mirrors the fields desktop's `RelayAgent` uses for mention eligibility
@@ -15,13 +18,15 @@ import '../../shared/relay/relay.dart';
 class AgentDirectoryEntry {
   final String pubkey;
   final String? displayName;
+  final String? ownerPubkey;
   final String? respondTo;
   final List<String> respondToAllowlist;
   final List<String> channelIds;
 
   const AgentDirectoryEntry({
     required this.pubkey,
     this.displayName,
+    this.ownerPubkey,
     this.respondTo,
     this.respondToAllowlist = const [],
     this.channelIds = const [],
@@ -66,7 +71,7 @@ final agentDirectoryProvider = FutureProvider<List<AgentDirectoryEntry>>((
   if (sessionState.status != SessionStatus.connected) return const [];
   final session = ref.read(relaySessionProvider.notifier);
   final events = await session.fetchHistory(NostrFilters.agentProfiles());
-  return [for (final event in events) AgentDirectoryEntry.fromEvent(event)];
+  return resolveAgentPolicies(session, events);
 });
 
 /// Verified NIP-OA owner pubkey per agent pubkey, from the agents' kind:0
@@ -80,8 +85,8 @@ final agentOwnersProvider = FutureProvider<Map<String, String>>((ref) async {
     NostrFilters.profilesBatch([for (final agent in agents) agent.pubkey]),
   );
   final owners = <String, String>{};
-  for (final event in events) {
-    final owner = verifiedOaOwnerPubkey(event.tags, event.pubkey);
+  for (final event in latestProfileEvents(events).values) {
+    final owner = verifiedOaOwnerPubkey(event);
     if (owner != null) owners[event.pubkey.toLowerCase()] = owner;
   }
   return owners;