diff --git a/activitypub.py b/activitypub.py
index f054339..41ef479 100644
--- a/activitypub.py
+++ b/activitypub.py
@@ -30,6 +30,7 @@ from common import (
     host_url,
     LOCAL_DOMAINS,
     PRIMARY_DOMAIN,
+    PROTOCOL_DOMAINS,
     redirect_wrap,
     subdomain_wrap,
     unwrap,
@@ -56,6 +57,8 @@ WEB_OPT_OUT_DOMAINS = None
 
 FEDI_URL_RE = re.compile(r'https://[^/]+/(@|users/)([^/@]+)(@[^/@]+)?(/(?:statuses/)?[0-9]+)?')
 
+_BOT_ACTOR_IDS = None
+
 
 def instance_actor():
     global _INSTANCE_ACTOR
@@ -65,6 +68,15 @@ def instance_actor():
     return _INSTANCE_ACTOR
 
 
+def bot_actor_ids():
+    global _BOT_ACTOR_IDS
+    if _BOT_ACTOR_IDS is None:
+        from activitypub import ActivityPub
+        _BOT_ACTOR_IDS = [translate_user_id(id=domain, from_=Web, to=ActivityPub)
+                          for domain in PROTOCOL_DOMAINS]
+    return _BOT_ACTOR_IDS
+
+
 class ActivityPub(User, Protocol):
     """ActivityPub protocol class.
 
@@ -926,6 +938,7 @@ def inbox(protocol=None, id=None):
     # follows, or other activity types, since Mastodon doesn't currently mark
     # those as explicitly public. Use as2's is_public instead of as1's because
     # as1's interprets unlisted as true.
+    # TODO: move this to Protocol
     if type == 'Create' and not as2.is_public(activity, unlisted=False):
         logger.info('Dropping non-public activity')
         return 'OK'
diff --git a/protocol.py b/protocol.py
index 98018f7..5c80cc6 100644
--- a/protocol.py
+++ b/protocol.py
@@ -804,6 +804,20 @@ class Protocol:
             from_user.disable_protocol(proto)
             return 'OK', 200
 
+        elif obj.type == 'post':
+            to_cc = (util.get_list(inner_obj_as1, 'to')
+                     + util.get_list(inner_obj_as1, 'cc'))
+            if len(to_cc) == 1 and to_cc[0] in PROTOCOL_DOMAINS:
+                content = inner_obj_as1.get('content').strip().lower()
+                logger.info(f'DM to bot user {to_cc}: {content}')
+                proto = Protocol.for_bridgy_subdomain(to_cc[0])
+                assert proto
+                if content in ('yes', 'ok'):
+                    from_user.enable_protocol(proto)
+                elif content == 'no':
+                    from_user.disable_protocol(proto)
+                return 'OK', 200
+
         # fetch actor if necessary
         if actor and actor.keys() == set(['id']):
             logger.info('Fetching actor so we have name, profile photo, etc')
diff --git a/tests/test_activitypub.py b/tests/test_activitypub.py
index 5d95b75..93174ac 100644
--- a/tests/test_activitypub.py
+++ b/tests/test_activitypub.py
@@ -829,6 +829,9 @@ class ActivityPubTest(TestCase):
     def test_inbox_unlisted(self, *mocks):
         self._test_inbox_with_to_ignored(['@unlisted'], *mocks)
 
+    def test_inbox_dm(self, *mocks):
+        self._test_inbox_with_to_ignored(['http://localhost/web/user.com'], *mocks)
+
     def _test_inbox_with_to_ignored(self, to, mock_head, mock_get, mock_post):
         Follower.get_or_create(to=self.make_user(ACTOR['id'], cls=ActivityPub),
                                from_=self.user)
diff --git a/tests/test_protocol.py b/tests/test_protocol.py
index 3c784d4..8b6d9f4 100644
--- a/tests/test_protocol.py
+++ b/tests/test_protocol.py
@@ -1796,7 +1796,7 @@ class ProtocolReceiveTest(TestCase):
         user = self.make_user('eefake:user', cls=ExplicitEnableFake)
         self.assertFalse(ExplicitEnableFake.is_enabled_to(Fake, user))
 
-        # protocol isn't enabled yet, block should be a noop
+        # fake protocol isn't enabled yet, block should be a noop
         self.assertEqual(('OK', 200), ExplicitEnableFake.receive_as1(block))
         user = user.key.get()
         self.assertEqual([], user.enabled_protocols)
@@ -1826,6 +1826,45 @@ class ProtocolReceiveTest(TestCase):
         self.assertEqual([], user.enabled_protocols)
         self.assertFalse(ExplicitEnableFake.is_enabled_to(Fake, user))
 
+    def test_dm_no_yes_sets_enabled_protocols(self):
+        dm = {
+            'objectType': 'note',
+            'id': 'eefake:dm',
+            'actor': 'eefake:user',
+            'to': ['fa.brid.gy'],
+            'content': 'no',
+        }
+
+        user = self.make_user('eefake:user', cls=ExplicitEnableFake)
+        self.assertFalse(ExplicitEnableFake.is_enabled_to(Fake, user))
+
+        # fake protocol isn't enabled yet, no DM should be a noop
+        self.assertEqual(('OK', 200), ExplicitEnableFake.receive_as1(dm))
+        user = user.key.get()
+        self.assertEqual([], user.enabled_protocols)
+
+        # yes DM should add to enabled_protocols
+        dm['id'] += '2'
+        dm['content'] = 'yes'
+        self.assertEqual(('OK', 200), ExplicitEnableFake.receive_as1(dm))
+        user = user.key.get()
+        self.assertEqual(['fake'], user.enabled_protocols)
+        self.assertTrue(ExplicitEnableFake.is_enabled_to(Fake, user))
+
+        # another yes DM should be a noop
+        dm['id'] += '3'
+        self.assertEqual(('OK', 200), ExplicitEnableFake.receive_as1(dm))
+        user = user.key.get()
+        self.assertEqual(['fake'], user.enabled_protocols)
+
+        # block should remove from enabled_protocols
+        dm['id'] += '4'
+        dm['content'] = ' \n NO  '
+        self.assertEqual(('OK', 200), ExplicitEnableFake.receive_as1(dm))
+        user = user.key.get()
+        self.assertEqual([], user.enabled_protocols)
+        self.assertFalse(ExplicitEnableFake.is_enabled_to(Fake, user))
+
     def test_receive_task_handler(self):
         note = {
             'id': 'fake:post',