Prevent silenced local users from notifying remote users not followin…

…g them (mastodon#10575)

* Prevent silenced local users from notifying remote users not following them

This is an attempt to extend the local restrictions of silenced users to the
federation.

* Add tests

* Add tests for making sure private status don't get sent over OStatus

app/lib/activitypub/tag_manager.rb

@@ -65,7 +65,14 @@ def to(status)
     when 'unlisted', 'private'
       [account_followers_url(status.account)]
     when 'direct', 'limited'
-      status.active_mentions.map { |mention| uri_for(mention.account) }
+      if status.account.silenced?
+        # Only notify followers if the account is locally silenced
+        account_ids = status.active_mentions.pluck(:account_id)
+        to = status.account.followers.where(id: account_ids).map { |account| uri_for(account) }
+        to.concat(FollowRequest.where(target_account_id: status.account_id, account_id: account_ids).map { |request| uri_for(request.account) })
+      else
+        status.active_mentions.map { |mention| uri_for(mention.account) }
+      end
     end
   end
 
@@ -86,7 +93,16 @@ def cc(status)
       cc << COLLECTIONS[:public]
     end
 
-    cc.concat(status.active_mentions.map { |mention| uri_for(mention.account) }) unless status.direct_visibility? || status.limited_visibility?
+    unless status.direct_visibility? || status.limited_visibility?
+      if status.account.silenced?
+        # Only notify followers if the account is locally silenced
+        account_ids = status.active_mentions.pluck(:account_id)
+        cc.concat(status.account.followers.where(id: account_ids).map { |account| uri_for(account) })
+        cc.concat(FollowRequest.where(target_account_id: status.account_id, account_id: account_ids).map { |request| uri_for(request.account) })
+      else
+        cc.concat(status.active_mentions.map { |mention| uri_for(mention.account) })
+      end
+    end
 
     cc
   end

spec/lib/activitypub/tag_manager_spec.rb

@@ -41,6 +41,22 @@
       status.mentions.create(account: mentioned)
       expect(subject.to(status)).to eq [subject.uri_for(mentioned)]
     end
+
+    it "returns URIs of mentions for direct silenced author's status only if they are followers or requesting to be" do
+      bob    = Fabricate(:account, username: 'bob')
+      alice  = Fabricate(:account, username: 'alice')
+      foo    = Fabricate(:account)
+      author = Fabricate(:account, username: 'author', silenced: true)
+      status = Fabricate(:status, visibility: :direct, account: author)
+      bob.follow!(author)
+      FollowRequest.create!(account: foo, target_account: author)
+      status.mentions.create(account: alice)
+      status.mentions.create(account: bob)
+      status.mentions.create(account: foo)
+      expect(subject.to(status)).to include(subject.uri_for(bob))
+      expect(subject.to(status)).to include(subject.uri_for(foo))
+      expect(subject.to(status)).to_not include(subject.uri_for(alice))
+    end
   end
 
   describe '#cc' do
@@ -70,6 +86,22 @@
       status.mentions.create(account: mentioned)
       expect(subject.cc(status)).to include(subject.uri_for(mentioned))
     end
+
+    it "returns URIs of mentions for silenced author's non-direct status only if they are followers or requesting to be" do
+      bob    = Fabricate(:account, username: 'bob')
+      alice  = Fabricate(:account, username: 'alice')
+      foo    = Fabricate(:account)
+      author = Fabricate(:account, username: 'author', silenced: true)
+      status = Fabricate(:status, visibility: :public, account: author)
+      bob.follow!(author)
+      FollowRequest.create!(account: foo, target_account: author)
+      status.mentions.create(account: alice)
+      status.mentions.create(account: bob)
+      status.mentions.create(account: foo)
+      expect(subject.cc(status)).to include(subject.uri_for(bob))
+      expect(subject.cc(status)).to include(subject.uri_for(foo))
+      expect(subject.cc(status)).to_not include(subject.uri_for(alice))
+    end
   end
 
   describe '#local_uri?' do

spec/services/process_mentions_service_spec.rb

@@ -1,10 +1,11 @@
 require 'rails_helper'
 
 RSpec.describe ProcessMentionsService, type: :service do
-  let(:account) { Fabricate(:account, username: 'alice') }
-  let(:status)  { Fabricate(:status, account: account, text: "Hello @#{remote_user.acct}") }
+  let(:account)    { Fabricate(:account, username: 'alice') }
+  let(:visibility) { :public }
+  let(:status)     { Fabricate(:status, account: account, text: "Hello @#{remote_user.acct}", visibility: visibility) }
 
-  context 'OStatus' do
+  context 'OStatus with public toot' do
     let(:remote_user) { Fabricate(:account, username: 'remote_user', protocol: :ostatus, domain: 'example.com', salmon_url: 'http://salmon.example.com') }
 
     subject { ProcessMentionsService.new }
@@ -23,6 +24,26 @@
     end
   end
 
+  context 'OStatus with private toot' do
+    let(:visibility)  { :private }
+    let(:remote_user) { Fabricate(:account, username: 'remote_user', protocol: :ostatus, domain: 'example.com', salmon_url: 'http://salmon.example.com') }
+
+    subject { ProcessMentionsService.new }
+
+    before do
+      stub_request(:post, remote_user.salmon_url)
+      subject.call(status)
+    end
+
+    it 'does not create a mention' do
+      expect(remote_user.mentions.where(status: status).count).to eq 0
+    end
+
+    it 'does not post to remote user\'s Salmon end point' do
+      expect(a_request(:post, remote_user.salmon_url)).to_not have_been_made
+    end
+  end
+
   context 'ActivityPub' do
     let(:remote_user) { Fabricate(:account, username: 'remote_user', protocol: :activitypub, domain: 'example.com', inbox_url: 'http://example.com/inbox') }