Merge branch 'master' into glitch-soc/merge-upstream

Conflicts:
- `app/controllers/accounts_controller.rb`:
  Upstream change too close to a glitch-soc change related to
  instance-local toots. Merged upstream changes.
- `app/services/fan_out_on_write_service.rb`:
  Minor conflict due to glitch-soc's handling of Direct Messages,
  merged upstream changes.
- `yarn.lock`:
  Not really a conflict, caused by glitch-soc-only dependencies
  being textually too close to updated upstream dependencies.
  Merged upstream changes.

4 files changed, 115 insertions, 26 deletions

diff --git a/app/lib/activitypub/activity.rb b/app/lib/activitypub/activity.rb
index ab946470b..94aee7939 100644
--- a/app/lib/activitypub/activity.rb
+++ b/app/lib/activitypub/activity.rb
@@ -71,7 +71,15 @@ class ActivityPub::Activity
   end
 
   def object_uri
-    @object_uri ||= value_or_id(@object)
+    @object_uri ||= begin
+      str = value_or_id(@object)
+
+      if str.start_with?('bear:')
+        Addressable::URI.parse(str).query_values['u']
+      else
+        str
+      end
+    end
   end
 
   def unsupported_object_type?
@@ -159,20 +167,20 @@ class ActivityPub::Activity
 
   def dereference_object!
     return unless @object.is_a?(String)
-    return if invalid_origin?(@object)
 
-    object = fetch_resource(@object, true, signed_fetch_account)
-    return unless object.present? && object.is_a?(Hash) && supported_context?(object)
+    dereferencer = ActivityPub::Dereferencer.new(@object, permitted_origin: @account.uri, signature_account: signed_fetch_account)
 
-    @object = object
+    @object = dereferencer.object unless dereferencer.object.nil?
   end
 
   def signed_fetch_account
+    return Account.find(@options[:delivered_to_account_id]) if @options[:delivered_to_account_id].present?
+
     first_mentioned_local_account || first_local_follower
   end
 
   def first_mentioned_local_account
-    audience = (as_array(@json['to']) + as_array(@json['cc'])).uniq
+    audience = (as_array(@json['to']) + as_array(@json['cc'])).map { |x| value_or_id(x) }.uniq
     local_usernames = audience.select { |uri| ActivityPub::TagManager.instance.local_uri?(uri) }
                               .map { |uri| ActivityPub::TagManager.instance.uri_to_local_id(uri, :username) }
 
diff --git a/app/lib/activitypub/activity/announce.rb b/app/lib/activitypub/activity/announce.rb
index 9e108985a..349e8f77e 100644
--- a/app/lib/activitypub/activity/announce.rb
+++ b/app/lib/activitypub/activity/announce.rb
@@ -34,12 +34,20 @@ class ActivityPub::Activity::Announce < ActivityPub::Activity
 
   private
 
+  def audience_to
+    as_array(@json['to']).map { |x| value_or_id(x) }
+  end
+
+  def audience_cc
+    as_array(@json['cc']).map { |x| value_or_id(x) }
+  end
+
   def visibility_from_audience
-    if equals_or_includes?(@json['to'], ActivityPub::TagManager::COLLECTIONS[:public])
+    if audience_to.include?(ActivityPub::TagManager::COLLECTIONS[:public])
       :public
-    elsif equals_or_includes?(@json['cc'], ActivityPub::TagManager::COLLECTIONS[:public])
+    elsif audience_cc.include?(ActivityPub::TagManager::COLLECTIONS[:public])
       :unlisted
-    elsif equals_or_includes?(@json['to'], @account.followers_url)
+    elsif audience_to.include?(@account.followers_url)
       :private
     else
       :direct
diff --git a/app/lib/activitypub/activity/create.rb b/app/lib/activitypub/activity/create.rb
index f09caaae4..3a9f83978 100644
--- a/app/lib/activitypub/activity/create.rb
+++ b/app/lib/activitypub/activity/create.rb
@@ -15,7 +15,7 @@ class ActivityPub::Activity::Create < ActivityPub::Activity
   private
 
   def create_encrypted_message
-    return reject_payload! if invalid_origin?(@object['id']) || @options[:delivered_to_account_id].blank?
+    return reject_payload! if invalid_origin?(object_uri) || @options[:delivered_to_account_id].blank?
 
     target_account = Account.find(@options[:delivered_to_account_id])
     target_device  = target_account.devices.find_by(device_id: @object.dig('to', 'deviceId'))
@@ -43,7 +43,7 @@ class ActivityPub::Activity::Create < ActivityPub::Activity
   end
 
   def create_status
-    return reject_payload! if unsupported_object_type? || invalid_origin?(@object['id']) || Tombstone.exists?(uri: @object['id']) || !related_to_local_activity?
+    return reject_payload! if unsupported_object_type? || invalid_origin?(object_uri) || tombstone_exists? || !related_to_local_activity?
 
     RedisLock.acquire(lock_options) do |lock|
       if lock.acquired?
@@ -65,11 +65,11 @@ class ActivityPub::Activity::Create < ActivityPub::Activity
   end
 
   def audience_to
-    @object['to'] || @json['to']
+    as_array(@object['to'] || @json['to']).map { |x| value_or_id(x) }
   end
 
   def audience_cc
-    @object['cc'] || @json['cc']
+    as_array(@object['cc'] || @json['cc']).map { |x| value_or_id(x) }
   end
 
   def process_status
@@ -90,7 +90,7 @@ class ActivityPub::Activity::Create < ActivityPub::Activity
     fetch_replies(@status)
     check_for_spam
     distribute(@status)
-    forward_for_reply if @status.distributable?
+    forward_for_reply
   end
 
   def find_existing_status
@@ -102,8 +102,8 @@ class ActivityPub::Activity::Create < ActivityPub::Activity
   def process_status_params
     @params = begin
       {
-        uri: @object['id'],
-        url: object_url || @object['id'],
+        uri: object_uri,
+        url: object_url || object_uri,
         account: @account,
         text: text_from_content || '',
         language: detected_language,
@@ -122,7 +122,7 @@ class ActivityPub::Activity::Create < ActivityPub::Activity
   end
 
   def process_audience
-    (as_array(audience_to) + as_array(audience_cc)).uniq.each do |audience|
+    (audience_to + audience_cc).uniq.each do |audience|
       next if audience == ActivityPub::TagManager::COLLECTIONS[:public]
 
       # Unlike with tags, there is no point in resolving accounts we don't already
@@ -313,7 +313,7 @@ class ActivityPub::Activity::Create < ActivityPub::Activity
     RedisLock.acquire(poll_lock_options) do |lock|
       if lock.acquired?
         already_voted = poll.votes.where(account: @account).exists?
-        poll.votes.create!(account: @account, choice: poll.options.index(@object['name']), uri: @object['id'])
+        poll.votes.create!(account: @account, choice: poll.options.index(@object['name']), uri: object_uri)
       else
         raise Mastodon::RaceConditionError
       end
@@ -352,11 +352,11 @@ class ActivityPub::Activity::Create < ActivityPub::Activity
   end
 
   def visibility_from_audience
-    if equals_or_includes?(audience_to, ActivityPub::TagManager::COLLECTIONS[:public])
+    if audience_to.include?(ActivityPub::TagManager::COLLECTIONS[:public])
       :public
-    elsif equals_or_includes?(audience_cc, ActivityPub::TagManager::COLLECTIONS[:public])
+    elsif audience_cc.include?(ActivityPub::TagManager::COLLECTIONS[:public])
       :unlisted
-    elsif equals_or_includes?(audience_to, @account.followers_url)
+    elsif audience_to.include?(@account.followers_url)
       :private
     elsif direct_message == false
       :limited
@@ -367,7 +367,7 @@ class ActivityPub::Activity::Create < ActivityPub::Activity
 
   def audience_includes?(account)
     uri = ActivityPub::TagManager.instance.uri_for(account)
-    equals_or_includes?(audience_to, uri) || equals_or_includes?(audience_cc, uri)
+    audience_to.include?(uri) || audience_cc.include?(uri)
   end
 
   def direct_message
@@ -391,7 +391,7 @@ class ActivityPub::Activity::Create < ActivityPub::Activity
   end
 
   def text_from_content
-    return Formatter.instance.linkify([[text_from_name, text_from_summary.presence].compact.join("\n\n"), object_url || @object['id']].join(' ')) if converted_object_type?
+    return Formatter.instance.linkify([[text_from_name, text_from_summary.presence].compact.join("\n\n"), object_url || object_uri].join(' ')) if converted_object_type?
 
     if @object['content'].present?
       @object['content']
@@ -483,19 +483,23 @@ class ActivityPub::Activity::Create < ActivityPub::Activity
   def addresses_local_accounts?
     return true if @options[:delivered_to_account_id]
 
-    local_usernames = (as_array(audience_to) + as_array(audience_cc)).uniq.select { |uri| ActivityPub::TagManager.instance.local_uri?(uri) }.map { |uri| ActivityPub::TagManager.instance.uri_to_local_id(uri, :username) }
+    local_usernames = (audience_to + audience_cc).uniq.select { |uri| ActivityPub::TagManager.instance.local_uri?(uri) }.map { |uri| ActivityPub::TagManager.instance.uri_to_local_id(uri, :username) }
 
     return false if local_usernames.empty?
 
     Account.local.where(username: local_usernames).exists?
   end
 
+  def tombstone_exists?
+    Tombstone.exists?(uri: object_uri)
+  end
+
   def check_for_spam
     SpamCheck.perform(@status)
   end
 
   def forward_for_reply
-    return unless @json['signature'].present? && reply_to_local?
+    return unless @status.distributable? && @json['signature'].present? && reply_to_local?
 
     ActivityPub::RawDistributionWorker.perform_async(Oj.dump(@json), replied_to_status.account_id, [@account.preferred_inbox_url])
   end
@@ -513,7 +517,7 @@ class ActivityPub::Activity::Create < ActivityPub::Activity
   end
 
   def lock_options
-    { redis: Redis.current, key: "create:#{@object['id']}" }
+    { redis: Redis.current, key: "create:#{object_uri}" }
   end
 
   def poll_lock_options
diff --git a/app/lib/activitypub/dereferencer.rb b/app/lib/activitypub/dereferencer.rb
new file mode 100644
index 000000000..bea69608f
--- /dev/null
+++ b/app/lib/activitypub/dereferencer.rb
@@ -0,0 +1,69 @@
+# frozen_string_literal: true
+
+class ActivityPub::Dereferencer
+  include JsonLdHelper
+
+  def initialize(uri, permitted_origin: nil, signature_account: nil)
+    @uri               = uri
+    @permitted_origin  = permitted_origin
+    @signature_account = signature_account
+  end
+
+  def object
+    @object ||= fetch_object!
+  end
+
+  private
+
+  def bear_cap?
+    @uri.start_with?('bear:')
+  end
+
+  def fetch_object!
+    if bear_cap?
+      fetch_with_token!
+    else
+      fetch_with_signature!
+    end
+  end
+
+  def fetch_with_token!
+    perform_request(bear_cap['u'], headers: { 'Authorization' => "Bearer #{bear_cap['t']}" })
+  end
+
+  def fetch_with_signature!
+    perform_request(@uri)
+  end
+
+  def bear_cap
+    @bear_cap ||= Addressable::URI.parse(@uri).query_values
+  end
+
+  def perform_request(uri, headers: nil)
+    return if invalid_origin?(uri)
+
+    req = Request.new(:get, uri)
+
+    req.add_headers('Accept' => 'application/activity+json, application/ld+json')
+    req.add_headers(headers) if headers
+    req.on_behalf_of(@signature_account) if @signature_account
+
+    req.perform do |res|
+      if res.code == 200
+        json = body_to_json(res.body_with_limit)
+        json if json.present? && json['id'] == uri
+      else
+        raise Mastodon::UnexpectedResponseError, res unless response_successful?(res) || response_error_unsalvageable?(res)
+      end
+    end
+  end
+
+  def invalid_origin?(uri)
+    return true if unsupported_uri_scheme?(uri)
+
+    needle   = Addressable::URI.parse(uri).host
+    haystack = Addressable::URI.parse(@permitted_origin).host
+
+    !haystack.casecmp(needle).zero?
+  end
+end