Merge tag 'v4.1.15'

* Fix insufficient Content-Type checking of fetched ActivityStreams objects

* Allow JSON-LD documents with multiple profiles

CHANGELOG.md

@@ -3,6 +3,59 @@ Changelog
 
 All notable changes to this project will be documented in this file.
 
+## [4.1.15] - 2024-02-16
+
+### Fixed
+
+- Fix OmniAuth tests and edge cases in error handling ([ClearlyClaire](https://github.com/mastodon/mastodon/pull/29201), [ClearlyClaire](https://github.com/mastodon/mastodon/pull/29207))
+
+### Security
+
+- Fix insufficient checking of remote posts ([GHSA-jhrq-qvrm-qr36](https://github.com/mastodon/mastodon/security/advisories/GHSA-jhrq-qvrm-qr36))
+
+## [4.1.14] - 2024-02-14
+
+### Security
+
+- Update the `sidekiq-unique-jobs` dependency (see [GHSA-cmh9-rx85-xj38](https://github.com/mhenrixon/sidekiq-unique-jobs/security/advisories/GHSA-cmh9-rx85-xj38))
+  In addition, we have disabled the web interface for `sidekiq-unique-jobs` out of caution.
+  If you need it, you can re-enable it by setting `ENABLE_SIDEKIQ_UNIQUE_JOBS_UI=true`.
+  If you only need to clear all locks, you can now use `bundle exec rake sidekiq_unique_jobs:delete_all_locks`.
+- Update the `nokogiri` dependency (see [GHSA-xc9x-jj77-9p9j](https://github.com/sparklemotion/nokogiri/security/advisories/GHSA-xc9x-jj77-9p9j))
+- Disable administrative Doorkeeper routes ([ThisIsMissEm](https://github.com/mastodon/mastodon/pull/29187))
+- Fix ongoing streaming sessions not being invalidated when applications get deleted in some cases ([GHSA-7w3c-p9j8-mq3x](https://github.com/mastodon/mastodon/security/advisories/GHSA-7w3c-p9j8-mq3x))
+  In some rare cases, the streaming server was not notified of access tokens revocation on application deletion.
+- Change external authentication behavior to never reattach a new identity to an existing user by default ([GHSA-vm39-j3vx-pch3](https://github.com/mastodon/mastodon/security/advisories/GHSA-vm39-j3vx-pch3))
+  Up until now, Mastodon has allowed new identities from external authentication providers to attach to an existing local user based on their verified e-mail address.
+  This allowed upgrading users from a database-stored password to an external authentication provider, or move from one authentication provider to another.
+  However, this behavior may be unexpected, and means that when multiple authentication providers are configured, the overall security would be that of the least secure authentication provider.
+  For these reasons, this behavior is now locked under the `ALLOW_UNSAFE_AUTH_PROVIDER_REATTACH` environment variable.
+  In addition, regardless of this environment variable, Mastodon will refuse to attach two identities from the same authentication provider to the same account.
+
+## [4.1.13] - 2024-02-01
+
+### Security
+
+- Fix insufficient origin validation (CVE-2024-23832, [GHSA-3fjr-858r-92rw](https://github.com/mastodon/mastodon/security/advisories/GHSA-3fjr-858r-92rw))
+
+## [4.1.12] - 2024-01-24
+
+### Fixed
+
+- Fix error when processing remote files with unusually long names ([ClearlyClaire](https://github.com/mastodon/mastodon/pull/28823))
+- Fix processing of compacted single-item JSON-LD collections ([ClearlyClaire](https://github.com/mastodon/mastodon/pull/28816))
+- Retry 401 errors on replies fetching ([ShadowJonathan](https://github.com/mastodon/mastodon/pull/28788))
+- Fix `RecordNotUnique` errors in LinkCrawlWorker ([tribela](https://github.com/mastodon/mastodon/pull/28748))
+- Fix Mastodon not correctly processing HTTP Signatures with query strings ([ClearlyClaire](https://github.com/mastodon/mastodon/pull/28443), [ClearlyClaire](https://github.com/mastodon/mastodon/pull/28476))
+- Fix potential redirection loop of streaming endpoint ([ClearlyClaire](https://github.com/mastodon/mastodon/pull/28665))
+- Fix streaming API redirection ignoring the port of `streaming_api_base_url` ([ClearlyClaire](https://github.com/mastodon/mastodon/pull/28558))
+- Fix `Undo Announce` activity not being sent to non-follower authors ([MitarashiDango](https://github.com/mastodon/mastodon/pull/18482))
+- Fix `LinkCrawlWorker` error when encountering empty OEmbed response ([ClearlyClaire](https://github.com/mastodon/mastodon/pull/28268))
+
+### Security
+
+- Add rate-limit of TOTP authentication attempts at controller level ([ClearlyClaire](https://github.com/mastodon/mastodon/pull/28801))
+
 ## [4.1.11] - 2023-12-04
 
 ### Changed

Gemfile.lock

@@ -405,7 +405,7 @@ GEM
       mime-types-data (~> 3.2015)
     mime-types-data (3.2022.0105)
     mini_mime (1.1.5)
-    mini_portile2 (2.8.4)
+    mini_portile2 (2.8.5)
     minitest (5.17.0)
     msgpack (1.6.0)
     multi_json (1.15.0)
@@ -424,8 +424,8 @@ GEM
       net-protocol
     net-ssh (7.0.1)
     nio4r (2.5.9)
-    nokogiri (1.14.5)
-      mini_portile2 (~> 2.8.0)
+    nokogiri (1.16.2)
+      mini_portile2 (~> 2.8.2)
       racc (~> 1.4)
     nsa (0.2.8)
       activesupport (>= 4.2, < 7)
@@ -468,7 +468,7 @@ GEM
     parslet (2.0.0)
     pastel (0.8.0)
       tty-color (~> 0.5)
-    pg (1.4.5)
+    pg (1.4.6)
     pghero (3.1.0)
       activerecord (>= 6)
     pkg-config (1.5.1)
@@ -496,7 +496,7 @@ GEM
     pundit (2.3.0)
       activesupport (>= 3.0.0)
     raabro (1.4.0)
-    racc (1.6.2)
+    racc (1.7.3)
     rack (2.2.8)
     rack-attack (6.6.1)
       rack (>= 1.0, < 3)
@@ -634,7 +634,7 @@ GEM
       activerecord (>= 4.0.0)
       railties (>= 4.0.0)
     semantic_range (3.0.0)
-    sidekiq (6.5.11)
+    sidekiq (6.5.12)
       connection_pool (>= 2.2.5, < 3)
       rack (~> 2.0)
       redis (>= 4.5.0, < 5)
@@ -645,7 +645,7 @@ GEM
       rufus-scheduler (~> 3.2)
       sidekiq (>= 4, < 7)
       tilt (>= 1.4.0)
-    sidekiq-unique-jobs (7.1.29)
+    sidekiq-unique-jobs (7.1.33)
       brpoplpush-redis_script (> 0.1.1, <= 2.0.0)
       concurrent-ruby (~> 1.0, >= 1.0.5)
       redis (< 5.0)

SECURITY.md

@@ -14,6 +14,4 @@ A "vulnerability in Mastodon" is a vulnerability in the code distributed through
 | ------- | ---------------- |
 | 4.2.x   | Yes              |
 | 4.1.x   | Yes              |
-| 4.0.x   | No               |
-| 3.5.x   | Until 2023-12-31 |
-| < 3.5   | No               |
+| < 4.1   | No               |

app/controllers/api/v1/streaming_controller.rb

@@ -2,7 +2,7 @@
 
 class Api::V1::StreamingController < Api::BaseController
   def index
-    if Rails.configuration.x.streaming_api_base_url == request.host
+    if same_host?
       not_found
     else
       redirect_to streaming_api_url, status: 301
@@ -11,9 +11,16 @@ class Api::V1::StreamingController < Api::BaseController
 
   private
 
+  def same_host?
+    base_url = Addressable::URI.parse(Rails.configuration.x.streaming_api_base_url)
+    request.host == base_url.host && request.port == (base_url.port || 80)
+  end
+
   def streaming_api_url
     Addressable::URI.parse(request.url).tap do |uri|
-      uri.host = Addressable::URI.parse(Rails.configuration.x.streaming_api_base_url).host
+      base_url = Addressable::URI.parse(Rails.configuration.x.streaming_api_base_url)
+      uri.host = base_url.host
+      uri.port = base_url.port
     end.to_s
   end
 end

app/controllers/auth/omniauth_callbacks_controller.rb

@@ -5,7 +5,7 @@ class Auth::OmniauthCallbacksController < Devise::OmniauthCallbacksController
 
   def self.provides_callback_for(provider)
     define_method provider do
-      @user = User.find_for_oauth(request.env['omniauth.auth'], current_user)
+      @user = User.find_for_omniauth(request.env['omniauth.auth'], current_user)
 
       if @user.persisted?
         LoginActivity.create(
@@ -24,6 +24,9 @@ class Auth::OmniauthCallbacksController < Devise::OmniauthCallbacksController
         session["devise.#{provider}_data"] = request.env['omniauth.auth']
         redirect_to new_user_registration_url
       end
+    rescue ActiveRecord::RecordInvalid
+      flash[:alert] = I18n.t('devise.failure.omniauth_user_creation_failure') if is_navigational_format?
+      redirect_to new_user_session_url
     end
   end
 

app/controllers/auth/sessions_controller.rb

@@ -1,6 +1,10 @@
 # frozen_string_literal: true
 
 class Auth::SessionsController < Devise::SessionsController
+  include Redisable
+
+  MAX_2FA_ATTEMPTS_PER_HOUR = 10
+
   layout 'auth'
 
   skip_before_action :require_no_authentication, only: [:create]
@@ -136,9 +140,23 @@ class Auth::SessionsController < Devise::SessionsController
     session.delete(:attempt_user_updated_at)
   end
 
+  def clear_2fa_attempt_from_user(user)
+    redis.del(second_factor_attempts_key(user))
+  end
+
+  def check_second_factor_rate_limits(user)
+    attempts, = redis.multi do |multi|
+      multi.incr(second_factor_attempts_key(user))
+      multi.expire(second_factor_attempts_key(user), 1.hour)
+    end
+
+    attempts >= MAX_2FA_ATTEMPTS_PER_HOUR
+  end
+
   def on_authentication_success(user, security_measure)
     @on_authentication_success_called = true
 
+    clear_2fa_attempt_from_user(user)
     clear_attempt_from_session
 
     user.update_sign_in!(new_sign_in: true)
@@ -170,4 +188,8 @@ class Auth::SessionsController < Devise::SessionsController
       user_agent: request.user_agent
     )
   end
+
+  def second_factor_attempts_key(user)
+    "2fa_auth_attempts:#{user.id}:#{Time.now.utc.hour}"
+  end
 end

app/controllers/concerns/signature_verification.rb

@@ -91,14 +91,23 @@ module SignatureVerification
     raise SignatureVerificationError, "Public key not found for key #{signature_params['keyId']}" if actor.nil?
 
     signature             = Base64.decode64(signature_params['signature'])
-    compare_signed_string = build_signed_string
+    compare_signed_string = build_signed_string(include_query_string: true)
 
     return actor unless verify_signature(actor, signature, compare_signed_string).nil?
 
+    # Compatibility quirk with older Mastodon versions
+    compare_signed_string = build_signed_string(include_query_string: false)
+    return actor unless verify_signature(actor, signature, compare_signed_string).nil?
+
     actor = stoplight_wrap_request { actor_refresh_key!(actor) }
 
     raise SignatureVerificationError, "Could not refresh public key #{signature_params['keyId']}" if actor.nil?
 
+    compare_signed_string = build_signed_string(include_query_string: true)
+    return actor unless verify_signature(actor, signature, compare_signed_string).nil?
+
+    # Compatibility quirk with older Mastodon versions
+    compare_signed_string = build_signed_string(include_query_string: false)
     return actor unless verify_signature(actor, signature, compare_signed_string).nil?
 
     fail_with! "Verification failed for #{actor.to_log_human_identifier} #{actor.uri} using rsa-sha256 (RSASSA-PKCS1-v1_5 with SHA-256)", signed_string: compare_signed_string, signature: signature_params['signature']
@@ -177,16 +186,24 @@ module SignatureVerification
     nil
   end
 
-  def build_signed_string
+  def build_signed_string(include_query_string: true)
     signed_headers.map do |signed_header|
-      if signed_header == Request::REQUEST_TARGET
-        "#{Request::REQUEST_TARGET}: #{request.method.downcase} #{request.path}"
-      elsif signed_header == '(created)'
+      case signed_header
+      when Request::REQUEST_TARGET
+        if include_query_string
+          "#{Request::REQUEST_TARGET}: #{request.method.downcase} #{request.original_fullpath}"
+        else
+          # Current versions of Mastodon incorrectly omit the query string from the (request-target) pseudo-header.
+          # Therefore, temporarily support such incorrect signatures for compatibility.
+          # TODO: remove eventually some time after release of the fixed version
+          "#{Request::REQUEST_TARGET}: #{request.method.downcase} #{request.path}"
+        end
+      when '(created)'
         raise SignatureVerificationError, 'Invalid pseudo-header (created) for rsa-sha256' unless signature_algorithm == 'hs2019'
         raise SignatureVerificationError, 'Pseudo-header (created) used but corresponding argument missing' if signature_params['created'].blank?
 
         "(created): #{signature_params['created']}"
-      elsif signed_header == '(expires)'
+      when '(expires)'
         raise SignatureVerificationError, 'Invalid pseudo-header (expires) for rsa-sha256' unless signature_algorithm == 'hs2019'
         raise SignatureVerificationError, 'Pseudo-header (expires) used but corresponding argument missing' if signature_params['expires'].blank?
 
@@ -246,7 +263,7 @@ module SignatureVerification
       stoplight_wrap_request { ResolveAccountService.new.call(key_id.gsub(/\Aacct:/, ''), suppress_errors: false) }
     elsif !ActivityPub::TagManager.instance.local_uri?(key_id)
       account   = ActivityPub::TagManager.instance.uri_to_actor(key_id)
-      account ||= stoplight_wrap_request { ActivityPub::FetchRemoteKeyService.new.call(key_id, id: false, suppress_errors: false) }
+      account ||= stoplight_wrap_request { ActivityPub::FetchRemoteKeyService.new.call(key_id, suppress_errors: false) }
       account
     end
   rescue Mastodon::PrivateNetworkAddressError => e

app/controllers/concerns/two_factor_authentication_concern.rb

@@ -65,6 +65,11 @@ module TwoFactorAuthenticationConcern
   end
 
   def authenticate_with_two_factor_via_otp(user)
+    if check_second_factor_rate_limits(user)
+      flash.now[:alert] = I18n.t('users.rate_limited')
+      return prompt_for_two_factor(user)
+    end
+
     if valid_otp_attempt?(user)
       on_authentication_success(user, :otp)
     else

app/helpers/jsonld_helper.rb

@@ -157,8 +157,8 @@ module JsonLdHelper
     end
   end
 
-  def fetch_resource(uri, id, on_behalf_of = nil)
-    unless id
+  def fetch_resource(uri, id_is_known, on_behalf_of = nil, request_options: {})
+    unless id_is_known
       json = fetch_resource_without_id_validation(uri, on_behalf_of)
 
       return if !json.is_a?(Hash) || unsupported_uri_scheme?(json['id'])
@@ -166,17 +166,29 @@ module JsonLdHelper
       uri = json['id']
     end
 
-    json = fetch_resource_without_id_validation(uri, on_behalf_of)
+    json = fetch_resource_without_id_validation(uri, on_behalf_of, request_options: request_options)
     json.present? && json['id'] == uri ? json : nil
   end
 
-  def fetch_resource_without_id_validation(uri, on_behalf_of = nil, raise_on_temporary_error = false)
+  def fetch_resource_without_id_validation(uri, on_behalf_of = nil, raise_on_temporary_error = false, request_options: {})
     on_behalf_of ||= Account.representative
 
-    build_request(uri, on_behalf_of).perform do |response|
+    build_request(uri, on_behalf_of, options: request_options).perform do |response|
       raise Mastodon::UnexpectedResponseError, response unless response_successful?(response) || response_error_unsalvageable?(response) || !raise_on_temporary_error
 
-      body_to_json(response.body_with_limit) if response.code == 200
+      body_to_json(response.body_with_limit) if response.code == 200 && valid_activitypub_content_type?(response)
+    end
+  end
+
+  def valid_activitypub_content_type?(response)
+    return true if response.mime_type == 'application/activity+json'
+
+    # When the mime type is `application/ld+json`, we need to check the profile,
+    # but `http.rb` does not parse it for us.
+    return false unless response.mime_type == 'application/ld+json'
+
+    response.headers[HTTP::Headers::CONTENT_TYPE]&.split(';')&.map(&:strip)&.any? do |str|
+      str.start_with?('profile="') && str[9...-1].split.include?('https://www.w3.org/ns/activitystreams')
     end
   end
 
@@ -206,8 +218,8 @@ module JsonLdHelper
     response.code == 501 || ((400...500).cover?(response.code) && ![401, 408, 429].include?(response.code))
   end
 
-  def build_request(uri, on_behalf_of = nil)
-    Request.new(:get, uri).tap do |request|
+  def build_request(uri, on_behalf_of = nil, options: {})
+    Request.new(:get, uri, **options).tap do |request|
       request.on_behalf_of(on_behalf_of) if on_behalf_of
       request.add_headers('Accept' => 'application/activity+json, application/ld+json')
     end

app/lib/activitypub/activity.rb

@@ -153,7 +153,8 @@ class ActivityPub::Activity
   def fetch_remote_original_status
     if object_uri.start_with?('http')
       return if ActivityPub::TagManager.instance.local_uri?(object_uri)
-      ActivityPub::FetchRemoteStatusService.new.call(object_uri, id: true, on_behalf_of: @account.followers.local.first, request_id: @options[:request_id])
+
+      ActivityPub::FetchRemoteStatusService.new.call(object_uri, on_behalf_of: @account.followers.local.first, request_id: @options[:request_id])
     elsif @object['url'].present?
       ::FetchRemoteStatusService.new.call(@object['url'], request_id: @options[:request_id])
     end

app/lib/activitypub/linked_data_signature.rb

@@ -19,7 +19,7 @@ class ActivityPub::LinkedDataSignature
     return unless type == 'RsaSignature2017'
 
     creator = ActivityPub::TagManager.instance.uri_to_actor(creator_uri)
-    creator = ActivityPub::FetchRemoteKeyService.new.call(creator_uri, id: false) if creator&.public_key.blank?
+    creator = ActivityPub::FetchRemoteKeyService.new.call(creator_uri) if creator&.public_key.blank?
 
     return if creator.nil?
 

app/lib/application_extension.rb

@@ -4,12 +4,32 @@ module ApplicationExtension
   extend ActiveSupport::Concern
 
   included do
+    include Redisable
+
     validates :name, length: { maximum: 60 }
     validates :website, url: true, length: { maximum: 2_000 }, if: :website?
     validates :redirect_uri, length: { maximum: 2_000 }
+
+    # The relationship used between Applications and AccessTokens is using
+    # dependent: delete_all, which means the ActiveRecord callback in
+    # AccessTokenExtension is not run, so instead we manually announce to
+    # streaming that these tokens are being deleted.
+    before_destroy :push_to_streaming_api, prepend: true
   end
 
   def confirmation_redirect_uri
     redirect_uri.lines.first.strip
   end
+
+  def push_to_streaming_api
+    # TODO: #28793 Combine into a single topic
+    payload = Oj.dump(event: :kill)
+    access_tokens.in_batches do |tokens|
+      redis.pipelined do |pipeline|
+        tokens.ids.each do |id|
+          pipeline.publish("timeline:access_token:#{id}", payload)
+        end
+      end
+    end
+  end
 end

app/lib/request.rb

@@ -77,6 +77,7 @@ class Request
     @url         = Addressable::URI.parse(url).normalize
     @http_client = options.delete(:http_client)
     @allow_local = options.delete(:allow_local)
+    @full_path   = options.delete(:with_query_string)
     @options     = options.merge(socket_class: use_proxy? || @allow_local ? ProxySocket : Socket)
     @options     = @options.merge(timeout_class: PerOperationWithDeadline, timeout_options: TIMEOUT)
     @options     = @options.merge(proxy_url) if use_proxy?
@@ -146,7 +147,7 @@ class Request
   private
 
   def set_common_headers!
-    @headers[REQUEST_TARGET]    = "#{@verb} #{@url.path}"
+    @headers[REQUEST_TARGET]    = request_target
     @headers['User-Agent']      = Mastodon::Version.user_agent
     @headers['Host']            = @url.host
     @headers['Date']            = Time.now.utc.httpdate
@@ -157,6 +158,14 @@ class Request
     @headers['Digest'] = "SHA-256=#{Digest::SHA256.base64digest(@options[:body])}"
   end
 
+  def request_target
+    if @url.query.nil? || !@full_path
+      "#{@verb} #{@url.path}"
+    else
+      "#{@verb} #{@url.path}?#{@url.query}"
+    end
+  end
+
   def signature
     algorithm = 'rsa-sha256'
     signature = Base64.strict_encode64(@keypair.sign(OpenSSL::Digest.new('SHA256'), signed_string))

app/lib/status_reach_finder.rb

@@ -16,28 +16,28 @@ class StatusReachFinder
   private
 
   def reached_account_inboxes
+    Account.where(id: reached_account_ids).inboxes
+  end
+
+  def reached_account_ids
     # When the status is a reblog, there are no interactions with it
     # directly, we assume all interactions are with the original one
 
     if @status.reblog?
-      []
+      [reblog_of_account_id]
     else
-      Account.where(id: reached_account_ids).inboxes
-    end
-  end
-
-  def reached_account_ids
-    [
-      replied_to_account_id,
-      reblog_of_account_id,
-      mentioned_account_ids,
-      reblogs_account_ids,
-      favourites_account_ids,
-      replies_account_ids,
-    ].tap do |arr|
-      arr.flatten!
-      arr.compact!
-      arr.uniq!
+      [
+        replied_to_account_id,
+        reblog_of_account_id,
+        mentioned_account_ids,
+        reblogs_account_ids,
+        favourites_account_ids,
+        replies_account_ids,
+      ].tap do |arr|
+        arr.flatten!
+        arr.compact!
+        arr.uniq!
+      end
     end
   end
 

app/models/account.rb

@@ -112,7 +112,7 @@ class Account < ApplicationRecord
   scope :matches_domain, ->(value) { where(arel_table[:domain].matches("%#{value}%")) }
   scope :without_unapproved, -> { left_outer_joins(:user).remote.or(left_outer_joins(:user).merge(User.approved.confirmed)) }
   scope :searchable, -> { without_unapproved.without_suspended.where(moved_to_account_id: nil) }
-  scope :discoverable, -> { searchable.without_silenced.where(discoverable: true).left_outer_joins(:account_stat) }
+  scope :discoverable, -> { searchable.without_silenced.where(discoverable: true).joins(:account_stat) }
   scope :followable_by, ->(account) { joins(arel_table.join(Follow.arel_table, Arel::Nodes::OuterJoin).on(arel_table[:id].eq(Follow.arel_table[:target_account_id]).and(Follow.arel_table[:account_id].eq(account.id))).join_sources).where(Follow.arel_table[:id].eq(nil)).joins(arel_table.join(FollowRequest.arel_table, Arel::Nodes::OuterJoin).on(arel_table[:id].eq(FollowRequest.arel_table[:target_account_id]).and(FollowRequest.arel_table[:account_id].eq(account.id))).join_sources).where(FollowRequest.arel_table[:id].eq(nil)) }
   scope :by_recent_status, -> { includes(:account_stat).merge(AccountStat.order('last_status_at DESC NULLS LAST')).references(:account_stat) }
   scope :by_recent_sign_in, -> { order(Arel.sql('users.current_sign_in_at DESC NULLS LAST')) }

app/models/concerns/omniauthable.rb

@@ -19,17 +19,18 @@ module Omniauthable
   end
 
   class_methods do
-    def find_for_oauth(auth, signed_in_resource = nil)
+    def find_for_omniauth(auth, signed_in_resource = nil)
       # EOLE-SSO Patch
       auth.uid = (auth.uid[0][:uid] || auth.uid[0][:user]) if auth.uid.is_a? Hashie::Array
-      identity = Identity.find_for_oauth(auth)
+      identity = Identity.find_for_omniauth(auth)
 
       # If a signed_in_resource is provided it always overrides the existing user
       # to prevent the identity being locked with accidentally created accounts.
       # Note that this may leave zombie accounts (with no associated identity) which
       # can be cleaned up at a later date.
       user   = signed_in_resource || identity.user
-      user ||= create_for_oauth(auth)
+      user ||= reattach_for_auth(auth)
+      user ||= create_for_auth(auth)
 
       if identity.user.nil?
         identity.user = user
@@ -39,19 +40,35 @@ module Omniauthable
       user
     end
 
-    def create_for_oauth(auth)
-      # Check if the user exists with provided email. If no email was provided,
+    private
+
+    def reattach_for_auth(auth)
+      # If allowed, check if a user exists with the provided email address,
+      # and return it if they does not have an associated identity with the
+      # current authentication provider.
+
+      # This can be used to provide a choice of alternative auth providers
+      # or provide smooth gradual transition between multiple auth providers,
+      # but this is discouraged because any insecure provider will put *all*
+      # local users at risk, regardless of which provider they registered with.
+
+      return unless ENV['ALLOW_UNSAFE_AUTH_PROVIDER_REATTACH'] == 'true'
+
+      email, email_is_verified = email_from_auth(auth)
+      return unless email_is_verified
+
+      user = User.find_by(email: email)
+      return if user.nil? || Identity.exists?(provider: auth.provider, user_id: user.id)
+
+      user
+    end
+
+    def create_for_auth(auth)
+      # Create a user for the given auth params. If no email was provided,
       # we assign a temporary email and ask the user to verify it on
       # the next step via Auth::SetupController.show
 
-      strategy          = Devise.omniauth_configs[auth.provider.to_sym].strategy
-      assume_verified   = strategy&.security&.assume_email_is_verified
-      email_is_verified = auth.info.verified || auth.info.verified_email || auth.info.email_verified || assume_verified
-      email             = auth.info.verified_email || auth.info.email
-
-      user = User.find_by(email: email) if email_is_verified
-
-      return user unless user.nil?
+      email, email_is_verified = email_from_auth(auth)
 
       user = User.new(user_params_from_auth(email, auth))
 
@@ -68,7 +85,14 @@ module Omniauthable
       user
     end
 
-    private
+    def email_from_auth(auth)
+      strategy          = Devise.omniauth_configs[auth.provider.to_sym].strategy
+      assume_verified   = strategy&.security&.assume_email_is_verified
+      email_is_verified = auth.info.verified || auth.info.verified_email || auth.info.email_verified || assume_verified
+      email             = auth.info.verified_email || auth.info.email
+
+      [email, email_is_verified]
+    end
 
     def user_params_from_auth(email, auth)
       {

app/models/identity.rb

@@ -16,7 +16,7 @@ class Identity < ApplicationRecord
   validates :uid, presence: true, uniqueness: { scope: :provider }
   validates :provider, presence: true
 
-  def self.find_for_oauth(auth)
+  def self.find_for_omniauth(auth)
     find_or_create_by(uid: auth.uid, provider: auth.provider)
   end
 end

app/models/user.rb

@@ -399,6 +399,16 @@ class User < ApplicationRecord
     Doorkeeper::AccessToken.by_resource_owner(self).in_batches do |batch|
       batch.update_all(revoked_at: Time.now.utc)
       Web::PushSubscription.where(access_token_id: batch).delete_all
+
+      # Revoke each access token for the Streaming API, since `update_all``
+      # doesn't trigger ActiveRecord Callbacks:
+      # TODO: #28793 Combine into a single topic
+      payload = Oj.dump(event: :kill)
+      redis.pipelined do |pipeline|
+        batch.ids.each do |id|
+          pipeline.publish("timeline:access_token:#{id}", payload)
+        end
+      end
     end
   end
 

app/services/activitypub/fetch_featured_collection_service.rb

@@ -23,9 +23,9 @@ class ActivityPub::FetchFeaturedCollectionService < BaseService
 
     case collection['type']
     when 'Collection', 'CollectionPage'
-      collection['items']
+      as_array(collection['items'])
     when 'OrderedCollection', 'OrderedCollectionPage'
-      collection['orderedItems']
+      as_array(collection['orderedItems'])
     end
   end
 

app/services/activitypub/fetch_remote_account_service.rb

@@ -2,7 +2,7 @@
 
 class ActivityPub::FetchRemoteAccountService < ActivityPub::FetchRemoteActorService
   # Does a WebFinger roundtrip on each call, unless `only_key` is true
-  def call(uri, id: true, prefetched_body: nil, break_on_redirect: false, only_key: false, suppress_errors: true, request_id: nil)
+  def call(uri, prefetched_body: nil, break_on_redirect: false, only_key: false, suppress_errors: true, request_id: nil)
     actor = super
     return actor if actor.nil? || actor.is_a?(Account)
 

app/services/activitypub/fetch_remote_actor_service.rb

@@ -10,15 +10,15 @@ class ActivityPub::FetchRemoteActorService < BaseService
   SUPPORTED_TYPES = %w(Application Group Organization Person Service).freeze
 
   # Does a WebFinger roundtrip on each call, unless `only_key` is true
-  def call(uri, id: true, prefetched_body: nil, break_on_redirect: false, only_key: false, suppress_errors: true, request_id: nil)
+  def call(uri, prefetched_body: nil, break_on_redirect: false, only_key: false, suppress_errors: true, request_id: nil)
     return if domain_not_allowed?(uri)
     return ActivityPub::TagManager.instance.uri_to_actor(uri) if ActivityPub::TagManager.instance.local_uri?(uri)
 
     @json = begin
       if prefetched_body.nil?
-        fetch_resource(uri, id)
+        fetch_resource(uri, true)
       else
-        body_to_json(prefetched_body, compare_id: id ? uri : nil)
+        body_to_json(prefetched_body, compare_id: uri)
       end
     rescue Oj::ParseError
       raise Error, "Error parsing JSON-LD document #{uri}"

app/services/activitypub/fetch_remote_key_service.rb

@@ -6,23 +6,10 @@ class ActivityPub::FetchRemoteKeyService < BaseService
   class Error < StandardError; end
 
   # Returns actor that owns the key
-  def call(uri, id: true, prefetched_body: nil, suppress_errors: true)
+  def call(uri, suppress_errors: true)
     raise Error, 'No key URI given' if uri.blank?
 
-    if prefetched_body.nil?
-      if id
-        @json = fetch_resource_without_id_validation(uri)
-        if actor_type?
-          @json = fetch_resource(@json['id'], true)
-        elsif uri != @json['id']
-          raise Error, "Fetched URI #{uri} has wrong id #{@json['id']}"
-        end
-      else
-        @json = fetch_resource(uri, id)
-      end
-    else
-      @json = body_to_json(prefetched_body, compare_id: id ? uri : nil)
-    end
+    @json = fetch_resource(uri, false)
 
     raise Error, "Unable to fetch key JSON at #{uri}" if @json.nil?
     raise Error, "Unsupported JSON-LD context for document #{uri}" unless supported_context?(@json)

app/services/activitypub/fetch_remote_status_service.rb

@@ -7,13 +7,13 @@ class ActivityPub::FetchRemoteStatusService < BaseService
   DISCOVERIES_PER_REQUEST = 1000
 
   # Should be called when uri has already been checked for locality
-  def call(uri, id: true, prefetched_body: nil, on_behalf_of: nil, expected_actor_uri: nil, request_id: nil)
+  def call(uri, prefetched_body: nil, on_behalf_of: nil, expected_actor_uri: nil, request_id: nil)
     @request_id = request_id || "#{Time.now.utc.to_i}-status-#{uri}"
     @json = begin
       if prefetched_body.nil?
-        fetch_resource(uri, id, on_behalf_of)
+        fetch_resource(uri, true, on_behalf_of)
       else
-        body_to_json(prefetched_body, compare_id: id ? uri : nil)
+        body_to_json(prefetched_body, compare_id: uri)
       end
     end
 
@@ -63,7 +63,7 @@ class ActivityPub::FetchRemoteStatusService < BaseService
 
   def account_from_uri(uri)
     actor = ActivityPub::TagManager.instance.uri_to_resource(uri, Account)
-    actor = ActivityPub::FetchRemoteAccountService.new.call(uri, id: true, request_id: @request_id) if actor.nil? || actor.possibly_stale?
+    actor = ActivityPub::FetchRemoteAccountService.new.call(uri, request_id: @request_id) if actor.nil? || actor.possibly_stale?
     actor
   end
 

app/services/activitypub/fetch_replies_service.rb

@@ -26,9 +26,9 @@ class ActivityPub::FetchRepliesService < BaseService
 
     case collection['type']
     when 'Collection', 'CollectionPage'
-      collection['items']
+      as_array(collection['items'])
     when 'OrderedCollection', 'OrderedCollectionPage'
-      collection['orderedItems']
+      as_array(collection['orderedItems'])
     end
   end
 
@@ -36,7 +36,21 @@ class ActivityPub::FetchRepliesService < BaseService
     return collection_or_uri if collection_or_uri.is_a?(Hash)
     return unless @allow_synchronous_requests
     return if invalid_origin?(collection_or_uri)
-    fetch_resource_without_id_validation(collection_or_uri, nil, true)
+
+    # NOTE: For backward compatibility reasons, Mastodon signs outgoing
+    # queries incorrectly by default.
+    #
+    # While this is relevant for all URLs with query strings, this is
+    # the only code path where this happens in practice.
+    #
+    # Therefore, retry with correct signatures if this fails.
+    begin
+      fetch_resource_without_id_validation(collection_or_uri, nil, true)
+    rescue Mastodon::UnexpectedResponseError => e
+      raise unless e.response && e.response.code == 401 && Addressable::URI.parse(collection_or_uri).query.present?
+
+      fetch_resource_without_id_validation(collection_or_uri, nil, true, request_options: { with_query_string: true })
+    end
   end
 
   def filtered_replies

app/services/activitypub/process_account_service.rb

@@ -274,7 +274,7 @@ class ActivityPub::ProcessAccountService < BaseService
 
   def moved_account
     account   = ActivityPub::TagManager.instance.uri_to_resource(@json['movedTo'], Account)
-    account ||= ActivityPub::FetchRemoteAccountService.new.call(@json['movedTo'], id: true, break_on_redirect: true, request_id: @options[:request_id])
+    account ||= ActivityPub::FetchRemoteAccountService.new.call(@json['movedTo'], break_on_redirect: true, request_id: @options[:request_id])
     account
   end
 

app/services/activitypub/synchronize_followers_service.rb

@@ -59,9 +59,9 @@ class ActivityPub::SynchronizeFollowersService < BaseService
 
     case collection['type']
     when 'Collection', 'CollectionPage'
-      collection['items']
+      as_array(collection['items'])
     when 'OrderedCollection', 'OrderedCollectionPage'
-      collection['orderedItems']
+      as_array(collection['orderedItems'])
     end
   end
 

app/services/fetch_oembed_service.rb

@@ -100,7 +100,7 @@ class FetchOEmbedService
   end
 
   def validate(oembed)
-    oembed if oembed[:version].to_s == '1.0' && oembed[:type].present?
+    oembed if oembed.present? && oembed[:version].to_s == '1.0' && oembed[:type].present?
   end
 
   def html

app/services/fetch_resource_service.rb

@@ -43,11 +43,19 @@ class FetchResourceService < BaseService
     @response_code = response.code
     return nil if response.code != 200
 
-    if ['application/activity+json', 'application/ld+json'].include?(response.mime_type)
+    if valid_activitypub_content_type?(response)
       body = response.body_with_limit
       json = body_to_json(body)
 
-      [json['id'], { prefetched_body: body, id: true }] if supported_context?(json) && (equals_or_includes_any?(json['type'], ActivityPub::FetchRemoteActorService::SUPPORTED_TYPES) || expected_type?(json))
+      return unless supported_context?(json) && (equals_or_includes_any?(json['type'], ActivityPub::FetchRemoteActorService::SUPPORTED_TYPES) || expected_type?(json))
+
+      if json['id'] != @url
+        return if terminal
+
+        return process(json['id'], terminal: true)
+      end
+
+      [@url, { prefetched_body: body }]
     elsif !terminal
       link_header = response['Link'] && parse_link_header(response)
 

app/services/keys/query_service.rb

@@ -69,7 +69,7 @@ class Keys::QueryService < BaseService
 
     return if json['items'].blank?
 
-    @devices = json['items'].map do |device|
+    @devices = as_array(json['items']).map do |device|
       Device.new(device_id: device['id'], name: device['name'], identity_key: device.dig('identityKey', 'publicKeyBase64'), fingerprint_key: device.dig('fingerprintKey', 'publicKeyBase64'), claim_url: device['claim'])
     end
   rescue HTTP::Error, OpenSSL::SSL::SSLError, Mastodon::Error => e

app/services/reblog_service.rb

@@ -45,11 +45,7 @@ class ReblogService < BaseService
   def create_notification(reblog)
     reblogged_status = reblog.reblog
 
-    if reblogged_status.account.local?
-      LocalNotificationWorker.perform_async(reblogged_status.account_id, reblog.id, reblog.class.name, 'reblog')
-    elsif reblogged_status.account.activitypub? && !reblogged_status.account.following?(reblog.account)
-      ActivityPub::DeliveryWorker.perform_async(build_json(reblog), reblog.account_id, reblogged_status.account.inbox_url)
-    end
+    LocalNotificationWorker.perform_async(reblogged_status.account_id, reblog.id, reblog.class.name, 'reblog') if reblogged_status.account.local?
   end
 
   def bump_potential_friendship(account, reblog)

app/workers/link_crawl_worker.rb

@@ -7,7 +7,7 @@ class LinkCrawlWorker
 
   def perform(status_id)
     FetchLinkCardService.new.call(Status.find(status_id))
-  rescue ActiveRecord::RecordNotFound
+  rescue ActiveRecord::RecordNotFound, ActiveRecord::RecordNotUnique
     true
   end
 end

config/initializers/doorkeeper.rb

@@ -19,9 +19,14 @@ Doorkeeper.configure do
     user unless user&.otp_required_for_login?
   end
 
-  # If you want to restrict access to the web interface for adding oauth authorized applications, you need to declare the block below.
+  # Doorkeeper provides some administrative interfaces for managing OAuth
+  # Applications, allowing creation, edit, and deletion of applications from the
+  # server. At present, these administrative routes are not integrated into
+  # Mastodon, and as such, we've disabled them by always return a 403 forbidden
+  # response for them. This does not affect the ability for users to manage
+  # their own OAuth Applications.
   admin_authenticator do
-    current_user&.admin? || redirect_to(new_user_session_url)
+    head 403
   end
 
   # Authorization Code expiration time (default 10 minutes).

config/locales/devise.en.yml

@@ -12,6 +12,7 @@ en:
       last_attempt: You have one more attempt before your account is locked.
       locked: Your account is locked.
       not_found_in_database: Invalid %{authentication_keys} or password.
+      omniauth_user_creation_failure: Error creating an account for this identity.
       pending: Your account is still under review.
       timeout: Your session expired. Please sign in again to continue.
       unauthenticated: You need to sign in or sign up before continuing.

config/locales/en.yml

@@ -1684,6 +1684,7 @@ en:
     follow_limit_reached: You cannot follow more than %{limit} people
     invalid_otp_token: Invalid two-factor code
     otp_lost_help_html: If you lost access to both, you may get in touch with %{email}
+    rate_limited: Too many authentication attempts, try again later.
     seamless_external_login: You are logged in via an external service, so password and e-mail settings are not available.
     signed_in_as: 'Signed in as:'
   verification:

config/routes.rb

@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-require 'sidekiq_unique_jobs/web'
+require 'sidekiq_unique_jobs/web' if ENV['ENABLE_SIDEKIQ_UNIQUE_JOBS_UI'] == true
 require 'sidekiq-scheduler/web'
 
 Rails.application.routes.draw do

docker-compose.yml

@@ -56,7 +56,7 @@ services:
 
   web:
     build: .
-    image: ghcr.io/mastodon/mastodon:v4.1.11
+    image: ghcr.io/mastodon/mastodon:v4.1.15
     restart: always
     env_file: .env.production
     command: bash -c "rm -f /mastodon/tmp/pids/server.pid; bundle exec rails s -p 3000"
@@ -77,7 +77,7 @@ services:
 
   streaming:
     build: .
-    image: ghcr.io/mastodon/mastodon:v4.1.11
+    image: ghcr.io/mastodon/mastodon:v4.1.15
     restart: always
     env_file: .env.production
     command: node ./streaming
@@ -95,7 +95,7 @@ services:
 
   sidekiq:
     build: .
-    image: ghcr.io/mastodon/mastodon:v4.1.11
+    image: ghcr.io/mastodon/mastodon:v4.1.15
     restart: always
     env_file: .env.production
     command: bundle exec sidekiq

lib/mastodon/version.rb

@@ -13,7 +13,7 @@ module Mastodon
     end
 
     def patch
-      11
+      15
     end
 
     def flags

lib/paperclip/response_with_limit_adapter.rb

@@ -16,7 +16,7 @@ module Paperclip
     private
 
     def cache_current_values
-      @original_filename = filename_from_content_disposition.presence || filename_from_path.presence || 'data'
+      @original_filename = truncated_filename
       @tempfile = copy_to_tempfile(@target)
       @content_type = ContentTypeDetector.new(@tempfile.path).detect
       @size = File.size(@tempfile)
@@ -43,6 +43,13 @@ module Paperclip
       source.response.connection.close
     end
 
+    def truncated_filename
+      filename = filename_from_content_disposition.presence || filename_from_path.presence || 'data'
+      extension = File.extname(filename)
+      basename = File.basename(filename, extension)
+      [basename[...20], extension[..4]].compact_blank.join
+    end
+
     def filename_from_content_disposition
       disposition = @target.response.headers['content-disposition']
       disposition&.match(/filename="([^"]*)"/)&.captures&.first

lib/tasks/sidekiq_unique_jobs.rake

@@ -0,0 +1,11 @@
+# frozen_string_literal: true
+
+namespace :sidekiq_unique_jobs do
+  task delete_all_locks: :environment do
+    digests = SidekiqUniqueJobs::Digests.new
+    digests.delete_by_pattern('*', count: digests.count)
+
+    expiring_digests = SidekiqUniqueJobs::ExpiringDigests.new
+    expiring_digests.delete_by_pattern('*', count: expiring_digests.count)
+  end
+end

spec/controllers/api/v1/streaming_controller_spec.rb

@@ -5,7 +5,7 @@ require 'rails_helper'
 describe Api::V1::StreamingController do
   around(:each) do |example|
     before = Rails.configuration.x.streaming_api_base_url
-    Rails.configuration.x.streaming_api_base_url = Rails.configuration.x.web_domain
+    Rails.configuration.x.streaming_api_base_url = "wss://#{Rails.configuration.x.web_domain}"
     example.run
     Rails.configuration.x.streaming_api_base_url = before
   end

spec/controllers/auth/sessions_controller_spec.rb

@@ -262,7 +262,27 @@ RSpec.describe Auth::SessionsController, type: :controller do
           end
         end
 
-        context 'using a valid OTP' do
+        context 'when repeatedly using an invalid TOTP code before using a valid code' do
+          before do
+            stub_const('Auth::SessionsController::MAX_2FA_ATTEMPTS_PER_HOUR', 2)
+          end
+
+          it 'does not log the user in' do
+            # Travel to the beginning of an hour to avoid crossing rate-limit buckets
+            travel_to '2023-12-20T10:00:00Z'
+
+            Auth::SessionsController::MAX_2FA_ATTEMPTS_PER_HOUR.times do
+              post :create, params: { user: { otp_attempt: '1234' } }, session: { attempt_user_id: user.id, attempt_user_updated_at: user.updated_at.to_s }
+              expect(controller.current_user).to be_nil
+            end
+
+            post :create, params: { user: { otp_attempt: user.current_otp } }, session: { attempt_user_id: user.id, attempt_user_updated_at: user.updated_at.to_s }
+            expect(controller.current_user).to be_nil
+            expect(flash[:alert]).to match I18n.t('users.rate_limited')
+          end
+        end
+
+        context 'when using a valid OTP' do
           before do
             post :create, params: { user: { otp_attempt: user.current_otp } }, session: { attempt_user_id: user.id, attempt_user_updated_at: user.updated_at.to_s }
           end

spec/controllers/concerns/signature_verification_spec.rb

@@ -1,303 +0,0 @@
-# frozen_string_literal: true
-
-require 'rails_helper'
-
-describe ApplicationController, type: :controller do
-  class WrappedActor
-    attr_reader :wrapped_account
-
-    def initialize(wrapped_account)
-      @wrapped_account = wrapped_account
-    end
-
-    delegate :uri, :keypair, to: :wrapped_account
-  end
-
-  controller do
-    include SignatureVerification
-
-    before_action :require_actor_signature!, only: [:signature_required]
-
-    def success
-      head 200
-    end
-
-    def alternative_success
-      head 200
-    end
-
-    def signature_required
-      head 200
-    end
-  end
-
-  before do
-    routes.draw do
-      match via: [:get, :post], 'success' => 'anonymous#success'
-      match via: [:get, :post], 'signature_required' => 'anonymous#signature_required'
-    end
-  end
-
-  context 'without signature header' do
-    before do
-      get :success
-    end
-
-    describe '#signed_request?' do
-      it 'returns false' do
-        expect(controller.signed_request?).to be false
-      end
-    end
-
-    describe '#signed_request_account' do
-      it 'returns nil' do
-        expect(controller.signed_request_account).to be_nil
-      end
-    end
-  end
-
-  context 'with signature header' do
-    let!(:author) { Fabricate(:account, domain: 'example.com', uri: 'https://example.com/actor') }
-
-    context 'without body' do
-      before do
-        get :success
-
-        fake_request = Request.new(:get, request.url)
-        fake_request.on_behalf_of(author)
-
-        request.headers.merge!(fake_request.headers)
-      end
-
-      describe '#signed_request?' do
-        it 'returns true' do
-          expect(controller.signed_request?).to be true
-        end
-      end
-
-      describe '#signed_request_account' do
-        it 'returns an account' do
-          expect(controller.signed_request_account).to eq author
-        end
-
-        it 'returns nil when path does not match' do
-          request.path = '/alternative-path'
-          expect(controller.signed_request_account).to be_nil
-        end
-
-        it 'returns nil when method does not match' do
-          post :success
-          expect(controller.signed_request_account).to be_nil
-        end
-      end
-    end
-
-    context 'with a valid actor that is not an Account' do
-      let(:actor) { WrappedActor.new(author) }
-
-      before do
-        get :success
-
-        fake_request = Request.new(:get, request.url)
-        fake_request.on_behalf_of(author)
-
-        request.headers.merge!(fake_request.headers)
-
-        allow(ActivityPub::TagManager.instance).to receive(:uri_to_actor).with(anything) do
-          actor
-        end
-      end
-
-      describe '#signed_request?' do
-        it 'returns true' do
-          expect(controller.signed_request?).to be true
-        end
-      end
-
-      describe '#signed_request_account' do
-        it 'returns nil' do
-          expect(controller.signed_request_account).to be_nil
-        end
-      end
-
-      describe '#signed_request_actor' do
-        it 'returns the expected actor' do
-          expect(controller.signed_request_actor).to eq actor
-        end
-      end
-    end
-
-    context 'with request with unparseable Date header' do
-      before do
-        get :success
-
-        fake_request = Request.new(:get, request.url)
-        fake_request.add_headers({ 'Date' => 'wrong date' })
-        fake_request.on_behalf_of(author)
-
-        request.headers.merge!(fake_request.headers)
-      end
-
-      describe '#signed_request?' do
-        it 'returns true' do
-          expect(controller.signed_request?).to be true
-        end
-      end
-
-      describe '#signed_request_account' do
-        it 'returns nil' do
-          expect(controller.signed_request_account).to be_nil
-        end
-      end
-
-      describe '#signature_verification_failure_reason' do
-        it 'contains an error description' do
-          controller.signed_request_account
-          expect(controller.signature_verification_failure_reason[:error]).to eq 'Invalid Date header: not RFC 2616 compliant date: "wrong date"'
-        end
-      end
-    end
-
-    context 'with request older than a day' do
-      before do
-        get :success
-
-        fake_request = Request.new(:get, request.url)
-        fake_request.add_headers({ 'Date' => 2.days.ago.utc.httpdate })
-        fake_request.on_behalf_of(author)
-
-        request.headers.merge!(fake_request.headers)
-      end
-
-      describe '#signed_request?' do
-        it 'returns true' do
-          expect(controller.signed_request?).to be true
-        end
-      end
-
-      describe '#signed_request_account' do
-        it 'returns nil' do
-          expect(controller.signed_request_account).to be_nil
-        end
-      end
-
-      describe '#signature_verification_failure_reason' do
-        it 'contains an error description' do
-          controller.signed_request_account
-          expect(controller.signature_verification_failure_reason[:error]).to eq 'Signed request date outside acceptable time window'
-        end
-      end
-    end
-
-    context 'with inaccessible key' do
-      before do
-        get :success
-
-        author = Fabricate(:account, domain: 'localhost:5000', uri: 'http://localhost:5000/actor')
-        fake_request = Request.new(:get, request.url)
-        fake_request.on_behalf_of(author)
-        author.destroy
-
-        request.headers.merge!(fake_request.headers)
-
-        stub_request(:get, 'http://localhost:5000/actor#main-key').to_raise(Mastodon::HostValidationError)
-      end
-
-      describe '#signed_request?' do
-        it 'returns true' do
-          expect(controller.signed_request?).to be true
-        end
-      end
-
-      describe '#signed_request_account' do
-        it 'returns nil' do
-          expect(controller.signed_request_account).to be_nil
-        end
-      end
-    end
-
-    context 'with body' do
-      before do
-        allow(controller).to receive(:actor_refresh_key!).and_return(author)
-        post :success, body: 'Hello world'
-
-        fake_request = Request.new(:post, request.url, body: 'Hello world')
-        fake_request.on_behalf_of(author)
-
-        request.headers.merge!(fake_request.headers)
-      end
-
-      describe '#signed_request?' do
-        it 'returns true' do
-          expect(controller.signed_request?).to be true
-        end
-      end
-
-      describe '#signed_request_account' do
-        it 'returns an account' do
-          expect(controller.signed_request_account).to eq author
-        end
-      end
-
-      context 'when path does not match' do
-        before do
-          request.path = '/alternative-path'
-        end
-
-        describe '#signed_request_account' do
-          it 'returns nil' do
-            expect(controller.signed_request_account).to be_nil
-          end
-        end
-
-        describe '#signature_verification_failure_reason' do
-          it 'contains an error description' do
-            controller.signed_request_account
-            expect(controller.signature_verification_failure_reason[:error]).to include('using rsa-sha256 (RSASSA-PKCS1-v1_5 with SHA-256)')
-            expect(controller.signature_verification_failure_reason[:signed_string]).to include("(request-target): post /alternative-path\n")
-          end
-        end
-      end
-
-      context 'when method does not match' do
-        before do
-          get :success
-        end
-
-        describe '#signed_request_account' do
-          it 'returns nil' do
-            expect(controller.signed_request_account).to be_nil
-          end
-        end
-      end
-
-      context 'when body has been tampered' do
-        before do
-          post :success, body: 'doo doo doo'
-        end
-
-        describe '#signed_request_account' do
-          it 'returns nil when body has been tampered' do
-            expect(controller.signed_request_account).to be_nil
-          end
-        end
-      end
-    end
-  end
-
-  context 'when a signature is required' do
-    before do
-      get :signature_required
-    end
-
-    context 'without signature header' do
-      it 'returns HTTP 401' do
-        expect(response).to have_http_status(401)
-      end
-
-      it 'returns an error' do
-        expect(Oj.load(response.body)['error']).to eq 'Request not signed'
-      end
-    end
-  end
-end

spec/helpers/jsonld_helper_spec.rb

@@ -56,15 +56,15 @@ describe JsonLdHelper do
   describe '#fetch_resource' do
     context 'when the second argument is false' do
       it 'returns resource even if the retrieved ID and the given URI does not match' do
-        stub_request(:get, 'https://bob.test/').to_return body: '{"id": "https://alice.test/"}'
-        stub_request(:get, 'https://alice.test/').to_return body: '{"id": "https://alice.test/"}'
+        stub_request(:get, 'https://bob.test/').to_return(body: '{"id": "https://alice.test/"}', headers: { 'Content-Type': 'application/activity+json' })
+        stub_request(:get, 'https://alice.test/').to_return(body: '{"id": "https://alice.test/"}', headers: { 'Content-Type': 'application/activity+json' })
 
         expect(fetch_resource('https://bob.test/', false)).to eq({ 'id' => 'https://alice.test/' })
       end
 
       it 'returns nil if the object identified by the given URI and the object identified by the retrieved ID does not match' do
-        stub_request(:get, 'https://mallory.test/').to_return body: '{"id": "https://marvin.test/"}'
-        stub_request(:get, 'https://marvin.test/').to_return body: '{"id": "https://alice.test/"}'
+        stub_request(:get, 'https://mallory.test/').to_return(body: '{"id": "https://marvin.test/"}', headers: { 'Content-Type': 'application/activity+json' })
+        stub_request(:get, 'https://marvin.test/').to_return(body: '{"id": "https://alice.test/"}', headers: { 'Content-Type': 'application/activity+json' })
 
         expect(fetch_resource('https://mallory.test/', false)).to eq nil
       end
@@ -72,7 +72,7 @@ describe JsonLdHelper do
 
     context 'when the second argument is true' do
       it 'returns nil if the retrieved ID and the given URI does not match' do
-        stub_request(:get, 'https://mallory.test/').to_return body: '{"id": "https://alice.test/"}'
+        stub_request(:get, 'https://mallory.test/').to_return(body: '{"id": "https://alice.test/"}', headers: { 'Content-Type': 'application/activity+json' })
         expect(fetch_resource('https://mallory.test/', true)).to eq nil
       end
     end
@@ -80,12 +80,12 @@ describe JsonLdHelper do
 
   describe '#fetch_resource_without_id_validation' do
     it 'returns nil if the status code is not 200' do
-      stub_request(:get, 'https://host.test/').to_return status: 400, body: '{}'
+      stub_request(:get, 'https://host.test/').to_return(status: 400, body: '{}', headers: { 'Content-Type': 'application/activity+json' })
       expect(fetch_resource_without_id_validation('https://host.test/')).to eq nil
     end
 
     it 'returns hash' do
-      stub_request(:get, 'https://host.test/').to_return status: 200, body: '{}'
+      stub_request(:get, 'https://host.test/').to_return(status: 200, body: '{}', headers: { 'Content-Type': 'application/activity+json' })
       expect(fetch_resource_without_id_validation('https://host.test/')).to eq({})
     end
   end

spec/lib/activitypub/activity/announce_spec.rb

@@ -33,7 +33,7 @@ RSpec.describe ActivityPub::Activity::Announce do
     context 'when sender is followed by a local account' do
       before do
         Fabricate(:account).follow!(sender)
-        stub_request(:get, 'https://example.com/actor/hello-world').to_return(body: Oj.dump(unknown_object_json))
+        stub_request(:get, 'https://example.com/actor/hello-world').to_return(body: Oj.dump(unknown_object_json), headers: { 'Content-Type': 'application/activity+json' })
         subject.perform
       end
 
@@ -118,7 +118,7 @@ RSpec.describe ActivityPub::Activity::Announce do
       subject { described_class.new(json, sender, relayed_through_actor: relay_account) }
 
       before do
-        stub_request(:get, 'https://example.com/actor/hello-world').to_return(body: Oj.dump(unknown_object_json))
+        stub_request(:get, 'https://example.com/actor/hello-world').to_return(body: Oj.dump(unknown_object_json), headers: { 'Content-Type': 'application/activity+json' })
       end
 
       context 'and the relay is enabled' do

spec/lib/activitypub/linked_data_signature_spec.rb

@@ -58,7 +58,7 @@ RSpec.describe ActivityPub::LinkedDataSignature do
 
         allow(ActivityPub::FetchRemoteKeyService).to receive(:new).and_return(service_stub)
 
-        allow(service_stub).to receive(:call).with('http://example.com/alice', id: false) do
+        allow(service_stub).to receive(:call).with('http://example.com/alice') do
           sender.update!(public_key: old_key)
           sender
         end
@@ -66,7 +66,7 @@ RSpec.describe ActivityPub::LinkedDataSignature do
 
       it 'fetches key and returns creator' do
         expect(subject.verify_actor!).to eq sender
-        expect(service_stub).to have_received(:call).with('http://example.com/alice', id: false).once
+        expect(service_stub).to have_received(:call).with('http://example.com/alice').once
       end
     end
 

spec/lib/activitypub/tag_manager_spec.rb

@@ -110,6 +110,14 @@ RSpec.describe ActivityPub::TagManager do
       expect(subject.cc(status)).to include(subject.uri_for(foo))
       expect(subject.cc(status)).to_not include(subject.uri_for(alice))
     end
+
+    it 'returns poster of reblogged post, if reblog' do
+      bob    = Fabricate(:account, username: 'bob', domain: 'example.com', inbox_url: 'http://example.com/bob')
+      alice  = Fabricate(:account, username: 'alice')
+      status = Fabricate(:status, visibility: :public, account: bob)
+      reblog = Fabricate(:status, visibility: :public, account: alice, reblog: status)
+      expect(subject.cc(reblog)).to include(subject.uri_for(bob))
+    end
   end
 
   describe '#local_uri?' do

spec/models/identity_spec.rb

@@ -1,16 +1,16 @@
 require 'rails_helper'
 
 RSpec.describe Identity, type: :model do
-  describe '.find_for_oauth' do
+  describe '.find_for_omniauth' do
     let(:auth) { Fabricate(:identity, user: Fabricate(:user)) }
 
     it 'calls .find_or_create_by' do
       expect(described_class).to receive(:find_or_create_by).with(uid: auth.uid, provider: auth.provider)
-      described_class.find_for_oauth(auth)
+      described_class.find_for_omniauth(auth)
     end
 
     it 'returns an instance of Identity' do
-      expect(described_class.find_for_oauth(auth)).to be_instance_of Identity
+      expect(described_class.find_for_omniauth(auth)).to be_instance_of Identity
     end
   end
 end

spec/models/user_spec.rb

@@ -439,7 +439,10 @@ RSpec.describe User, type: :model do
     let!(:access_token) { Fabricate(:access_token, resource_owner_id: user.id) }
     let!(:web_push_subscription) { Fabricate(:web_push_subscription, access_token: access_token) }
 
+    let(:redis_pipeline_stub) { instance_double(Redis::Namespace, publish: nil) }
+
     before do
+      allow(redis).to receive(:pipelined).and_yield(redis_pipeline_stub)
       user.reset_password!
     end
 
@@ -455,6 +458,10 @@ RSpec.describe User, type: :model do
       expect(Doorkeeper::AccessToken.active_for(user).count).to eq 0
     end
 
+    it 'revokes streaming access for all access tokens' do
+      expect(redis_pipeline_stub).to have_received(:publish).with("timeline:access_token:#{access_token.id}", Oj.dump(event: :kill)).once
+    end
+
     it 'removes push subscriptions' do
       expect(Web::PushSubscription.where(user: user).or(Web::PushSubscription.where(access_token: access_token)).count).to eq 0
     end

spec/requests/api/v1/directories_spec.rb

@@ -0,0 +1,139 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+describe 'Directories API' do
+  let(:user)    { Fabricate(:user, confirmed_at: nil) }
+  let(:token)   { Fabricate(:accessible_access_token, resource_owner_id: user.id, scopes: scopes) }
+  let(:scopes)  { 'read:follows' }
+  let(:headers) { { 'Authorization' => "Bearer #{token.token}" } }
+
+  describe 'GET /api/v1/directories' do
+    context 'with no params' do
+      before do
+        local_unconfirmed_account = Fabricate(
+          :account,
+          domain: nil,
+          user: Fabricate(:user, confirmed_at: nil, approved: true),
+          username: 'local_unconfirmed'
+        )
+        local_unconfirmed_account.create_account_stat!
+
+        local_unapproved_account = Fabricate(
+          :account,
+          domain: nil,
+          user: Fabricate(:user, confirmed_at: 10.days.ago),
+          username: 'local_unapproved'
+        )
+        local_unapproved_account.create_account_stat!
+        local_unapproved_account.user.update(approved: false)
+
+        local_undiscoverable_account = Fabricate(
+          :account,
+          domain: nil,
+          user: Fabricate(:user, confirmed_at: 10.days.ago, approved: true),
+          discoverable: false,
+          username: 'local_undiscoverable'
+        )
+        local_undiscoverable_account.create_account_stat!
+
+        excluded_from_timeline_account = Fabricate(
+          :account,
+          domain: 'host.example',
+          discoverable: true,
+          username: 'remote_excluded_from_timeline'
+        )
+        excluded_from_timeline_account.create_account_stat!
+        Fabricate(:block, account: user.account, target_account: excluded_from_timeline_account)
+
+        domain_blocked_account = Fabricate(
+          :account,
+          domain: 'test.example',
+          discoverable: true,
+          username: 'remote_domain_blocked'
+        )
+        domain_blocked_account.create_account_stat!
+        Fabricate(:account_domain_block, account: user.account, domain: 'test.example')
+
+        local_discoverable_account.create_account_stat!
+        eligible_remote_account.create_account_stat!
+      end
+
+      let(:local_discoverable_account) do
+        Fabricate(
+          :account,
+          domain: nil,
+          user: Fabricate(:user, confirmed_at: 10.days.ago, approved: true),
+          discoverable: true,
+          username: 'local_discoverable'
+        )
+      end
+
+      let(:eligible_remote_account) do
+        Fabricate(
+          :account,
+          domain: 'host.example',
+          discoverable: true,
+          username: 'eligible_remote'
+        )
+      end
+
+      it 'returns the local discoverable account and the remote discoverable account' do
+        get '/api/v1/directory', headers: headers
+
+        expect(response).to have_http_status(200)
+        expect(body_as_json.size).to eq(2)
+        expect(body_as_json.pluck(:id)).to contain_exactly(eligible_remote_account.id.to_s, local_discoverable_account.id.to_s)
+      end
+    end
+
+    context 'when asking for local accounts only' do
+      let(:user) { Fabricate(:user, confirmed_at: 10.days.ago, approved: true) }
+      let(:local_account) { Fabricate(:account, domain: nil, user: user) }
+      let(:remote_account) { Fabricate(:account, domain: 'host.example') }
+
+      before do
+        local_account.create_account_stat!
+        remote_account.create_account_stat!
+      end
+
+      it 'returns only the local accounts' do
+        get '/api/v1/directory', headers: headers, params: { local: '1' }
+
+        expect(response).to have_http_status(200)
+        expect(body_as_json.size).to eq(1)
+        expect(body_as_json.first[:id]).to include(local_account.id.to_s)
+        expect(response.body).to_not include(remote_account.id.to_s)
+      end
+    end
+
+    context 'when ordered by active' do
+      it 'returns accounts in order of most recent status activity' do
+        old_stat = Fabricate(:account_stat, last_status_at: 1.day.ago)
+        new_stat = Fabricate(:account_stat, last_status_at: 1.minute.ago)
+
+        get '/api/v1/directory', headers: headers, params: { order: 'active' }
+
+        expect(response).to have_http_status(200)
+        expect(body_as_json.size).to eq(2)
+        expect(body_as_json.first[:id]).to include(new_stat.account_id.to_s)
+        expect(body_as_json.second[:id]).to include(old_stat.account_id.to_s)
+      end
+    end
+
+    context 'when ordered by new' do
+      it 'returns accounts in order of creation' do
+        account_old = Fabricate(:account_stat).account
+        travel_to 10.seconds.from_now
+        account_new = Fabricate(:account_stat).account
+
+        get '/api/v1/directory', headers: headers, params: { order: 'new' }
+
+        expect(response).to have_http_status(200)
+        expect(body_as_json.size).to eq(2)
+        expect(body_as_json.first[:id]).to include(account_new.id.to_s)
+        expect(body_as_json.second[:id]).to include(account_old.id.to_s)
+      end
+    end
+  end
+end

spec/requests/disabled_oauth_endpoints_spec.rb

@@ -0,0 +1,83 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+describe 'Disabled OAuth routes' do
+  # These routes are disabled via the doorkeeper configuration for
+  # `admin_authenticator`, as these routes should only be accessible by server
+  # administrators. For now, these routes are not properly designed and
+  # integrated into Mastodon, so we're disabling them completely
+  describe 'GET /oauth/applications' do
+    it 'returns 403 forbidden' do
+      get oauth_applications_path
+
+      expect(response).to have_http_status(403)
+    end
+  end
+
+  describe 'POST /oauth/applications' do
+    it 'returns 403 forbidden' do
+      post oauth_applications_path
+
+      expect(response).to have_http_status(403)
+    end
+  end
+
+  describe 'GET /oauth/applications/new' do
+    it 'returns 403 forbidden' do
+      get new_oauth_application_path
+
+      expect(response).to have_http_status(403)
+    end
+  end
+
+  describe 'GET /oauth/applications/:id' do
+    let(:application) { Fabricate(:application, scopes: 'read') }
+
+    it 'returns 403 forbidden' do
+      get oauth_application_path(application)
+
+      expect(response).to have_http_status(403)
+    end
+  end
+
+  describe 'PATCH /oauth/applications/:id' do
+    let(:application) { Fabricate(:application, scopes: 'read') }
+
+    it 'returns 403 forbidden' do
+      patch oauth_application_path(application)
+
+      expect(response).to have_http_status(403)
+    end
+  end
+
+  describe 'PUT /oauth/applications/:id' do
+    let(:application) { Fabricate(:application, scopes: 'read') }
+
+    it 'returns 403 forbidden' do
+      put oauth_application_path(application)
+
+      expect(response).to have_http_status(403)
+    end
+  end
+
+  describe 'DELETE /oauth/applications/:id' do
+    let(:application) { Fabricate(:application, scopes: 'read') }
+
+    it 'returns 403 forbidden' do
+      delete oauth_application_path(application)
+
+      expect(response).to have_http_status(403)
+    end
+  end
+
+  describe 'GET /oauth/applications/:id/edit' do
+    let(:application) { Fabricate(:application, scopes: 'read') }
+
+    it 'returns 403 forbidden' do
+      get edit_oauth_application_path(application)
+
+      expect(response).to have_http_status(403)
+    end
+  end
+end

spec/requests/omniauth_callbacks_spec.rb

@@ -0,0 +1,143 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+describe 'OmniAuth callbacks' do
+  shared_examples 'omniauth provider callbacks' do |provider|
+    subject { post send :"user_#{provider}_omniauth_callback_path" }
+
+    context 'with full information in response' do
+      before do
+        mock_omniauth(provider, {
+          provider: provider.to_s,
+          uid: '123',
+          info: {
+            verified: 'true',
+            email: 'user@host.example',
+          },
+        })
+      end
+
+      context 'without a matching user' do
+        it 'creates a user and an identity and redirects to root path' do
+          expect { subject }
+            .to change(User, :count)
+            .by(1)
+            .and change(Identity, :count)
+            .by(1)
+            .and change(LoginActivity, :count)
+            .by(1)
+
+          expect(User.last.email).to eq('user@host.example')
+          expect(Identity.find_by(user: User.last).uid).to eq('123')
+          expect(response).to redirect_to(root_path)
+        end
+      end
+
+      context 'with a matching user and no matching identity' do
+        before do
+          Fabricate(:user, email: 'user@host.example')
+        end
+
+        context 'when ALLOW_UNSAFE_AUTH_PROVIDER_REATTACH is set to true' do
+          around do |example|
+            ClimateControl.modify ALLOW_UNSAFE_AUTH_PROVIDER_REATTACH: 'true' do
+              example.run
+            end
+          end
+
+          it 'matches the existing user, creates an identity, and redirects to root path' do
+            expect { subject }
+              .to not_change(User, :count)
+              .and change(Identity, :count)
+              .by(1)
+              .and change(LoginActivity, :count)
+              .by(1)
+
+            expect(Identity.find_by(user: User.last).uid).to eq('123')
+            expect(response).to redirect_to(root_path)
+          end
+        end
+
+        context 'when ALLOW_UNSAFE_AUTH_PROVIDER_REATTACH is not set to true' do
+          it 'does not match the existing user or create an identity, and redirects to login page' do
+            expect { subject }
+              .to not_change(User, :count)
+              .and not_change(Identity, :count)
+              .and not_change(LoginActivity, :count)
+
+            expect(response).to redirect_to(new_user_session_url)
+          end
+        end
+      end
+
+      context 'with a matching user and a matching identity' do
+        before do
+          user = Fabricate(:user, email: 'user@host.example')
+          Fabricate(:identity, user: user, uid: '123', provider: provider)
+        end
+
+        it 'matches the existing records and redirects to root path' do
+          expect { subject }
+            .to not_change(User, :count)
+            .and not_change(Identity, :count)
+            .and change(LoginActivity, :count)
+            .by(1)
+
+          expect(response).to redirect_to(root_path)
+        end
+      end
+    end
+
+    context 'with a response missing email address' do
+      before do
+        mock_omniauth(provider, {
+          provider: provider.to_s,
+          uid: '123',
+          info: {
+            verified: 'true',
+          },
+        })
+      end
+
+      it 'redirects to the auth setup page' do
+        expect { subject }
+          .to change(User, :count)
+          .by(1)
+          .and change(Identity, :count)
+          .by(1)
+          .and change(LoginActivity, :count)
+          .by(1)
+
+        expect(response).to redirect_to(auth_setup_path(missing_email: '1'))
+      end
+    end
+
+    context 'when a user cannot be built' do
+      before do
+        allow(User).to receive(:find_for_omniauth).and_return(User.new)
+      end
+
+      it 'redirects to the new user signup page' do
+        expect { subject }
+          .to not_change(User, :count)
+          .and not_change(Identity, :count)
+          .and not_change(LoginActivity, :count)
+
+        expect(response).to redirect_to(new_user_registration_url)
+      end
+    end
+  end
+
+  describe '#openid_connect', if: ENV['OIDC_ENABLED'] == 'true' && ENV['OIDC_SCOPE'].present? do
+    include_examples 'omniauth provider callbacks', :openid_connect
+  end
+
+  describe '#cas', if: ENV['CAS_ENABLED'] == 'true' do
+    include_examples 'omniauth provider callbacks', :cas
+  end
+
+  describe '#saml', if: ENV['SAML_ENABLED'] == 'true' do
+    include_examples 'omniauth provider callbacks', :saml
+  end
+end

spec/requests/signature_verification_spec.rb

@@ -0,0 +1,398 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+describe 'signature verification concern' do
+  before do
+    stub_tests_controller
+
+    # Signature checking is time-dependent, so travel to a fixed date
+    travel_to '2023-12-20T10:00:00Z'
+  end
+
+  after { Rails.application.reload_routes! }
+
+  # Include the private key so the tests can be easily adjusted and reviewed
+  let(:actor_keypair) do
+    OpenSSL::PKey.read(<<~PEM_TEXT)
+      -----BEGIN RSA PRIVATE KEY-----
+      MIIEowIBAAKCAQEAqIAYvNFGbZ5g4iiK6feSdXD4bDStFM58A7tHycYXaYtzZQpI
+      eHXAmaXuZzXIwtrP4N0gIk8JNwZvXj2UPS+S07t0V9wNK94he01LV5EMz/GN4eNn
+      FmDL64HIEuKLvV8TvgjbUPRD6Y5X0UpKi2ZIFLSb96Q5w0Z/k7ntpVKV52y8kz5F
+      jr/O/0JuHryZe0yItzJh8kzFfeMf0EXzfSnaKvT7P9jhgC6uTre+jXyvVZjiHDrn
+      qvvucdI3I7DRfXo1OqARBrLjy+TdseUAjNYJ+OuPRI1URIWQI01DCHqcohVu9+Ar
+      +BiCjFp3ua+XMuJvrvbD61d1Fvig/9nbBRR+8QIDAQABAoIBAAgySHnFWI6gItR3
+      fkfiqIm80cHCN3Xk1C6iiVu+3oBOZbHpW9R7vl9e/WOA/9O+LPjiSsQOegtWnVvd
+      RRjrl7Hj20VDlZKv5Mssm6zOGAxksrcVbqwdj+fUJaNJCL0AyyseH0x/IE9T8rDC
+      I1GH+3tB3JkhkIN/qjipdX5ab8MswEPu8IC4ViTpdBgWYY/xBcAHPw4xuL0tcwzh
+      FBlf4DqoEVQo8GdK5GAJ2Ny0S4xbXHUURzx/R4y4CCts7niAiLGqd9jmLU1kUTMk
+      QcXfQYK6l+unLc7wDYAz7sFEHh04M48VjWwiIZJnlCqmQbLda7uhhu8zkF1DqZTu
+      ulWDGQECgYEA0TIAc8BQBVab979DHEEmMdgqBwxLY3OIAk0b+r50h7VBGWCDPRsC
+      STD73fQY3lNet/7/jgSGwwAlAJ5PpMXxXiZAE3bUwPmHzgF7pvIOOLhA8O07tHSO
+      L2mvQe6NPzjZ+6iAO2U9PkClxcvGvPx2OBvisfHqZLmxC9PIVxzruQECgYEAzjM6
+      BTUXa6T/qHvLFbN699BXsUOGmHBGaLRapFDBfVvgZrwqYQcZpBBhesLdGTGSqwE7
+      gWsITPIJ+Ldo+38oGYyVys+w/V67q6ud7hgSDTW3hSvm+GboCjk6gzxlt9hQ0t9X
+      8vfDOYhEXvVUJNv3mYO60ENqQhILO4bQ0zi+VfECgYBb/nUccfG+pzunU0Cb6Dp3
+      qOuydcGhVmj1OhuXxLFSDG84Tazo7juvHA9mp7VX76mzmDuhpHPuxN2AzB2SBEoE
+      cSW0aYld413JRfWukLuYTc6hJHIhBTCRwRQFFnae2s1hUdQySm8INT2xIc+fxBXo
+      zrp+Ljg5Wz90SAnN5TX0AQKBgDaatDOq0o/r+tPYLHiLtfWoE4Dau+rkWJDjqdk3
+      lXWn/e3WyHY3Vh/vQpEqxzgju45TXjmwaVtPATr+/usSykCxzP0PMPR3wMT+Rm1F
+      rIoY/odij+CaB7qlWwxj0x/zRbwB7x1lZSp4HnrzBpxYL+JUUwVRxPLIKndSBTza
+      GvVRAoGBAIVBcNcRQYF4fvZjDKAb4fdBsEuHmycqtRCsnkGOz6ebbEQznSaZ0tZE
+      +JuouZaGjyp8uPjNGD5D7mIGbyoZ3KyG4mTXNxDAGBso1hrNDKGBOrGaPhZx8LgO
+      4VXJ+ybXrATf4jr8ccZYsZdFpOphPzz+j55Mqg5vac5P1XjmsGTb
+      -----END RSA PRIVATE KEY-----
+    PEM_TEXT
+  end
+
+  context 'without a Signature header' do
+    it 'does not treat the request as signed' do
+      get '/activitypub/success'
+
+      expect(response).to have_http_status(200)
+      expect(body_as_json).to match(
+        signed_request: false,
+        signature_actor_id: nil,
+        error: 'Request not signed'
+      )
+    end
+
+    context 'when a signature is required' do
+      it 'returns http unauthorized with appropriate error' do
+        get '/activitypub/signature_required'
+
+        expect(response).to have_http_status(401)
+        expect(body_as_json).to match(
+          error: 'Request not signed'
+        )
+      end
+    end
+  end
+
+  context 'with an HTTP Signature from a known account' do
+    let!(:actor) { Fabricate(:account, domain: 'remote.domain', uri: 'https://remote.domain/users/bob', private_key: nil, public_key: actor_keypair.public_key.to_pem) }
+
+    context 'with a valid signature on a GET request' do
+      let(:signature_header) do
+        'keyId="https://remote.domain/users/bob#main-key",algorithm="rsa-sha256",headers="date host (request-target)",signature="Z8ilar3J7bOwqZkMp7sL8sRs4B1FT+UorbmvWoE+A5UeoOJ3KBcUmbsh+k3wQwbP5gMNUrra9rEWabpasZGphLsbDxfbsWL3Cf0PllAc7c1c7AFEwnewtExI83/qqgEkfWc2z7UDutXc2NfgAx89Ox8DXU/fA2GG0jILjB6UpFyNugkY9rg6oI31UnvfVi3R7sr3/x8Ea3I9thPvqI2byF6cojknSpDAwYzeKdngX3TAQEGzFHz3SDWwyp3jeMWfwvVVbM38FxhvAnSumw7YwWW4L7M7h4M68isLimoT3yfCn2ucBVL5Dz8koBpYf/40w7QidClAwCafZQFC29yDOg=="' # rubocop:disable Layout/LineLength
+      end
+
+      it 'successfuly verifies signature', :aggregate_failures do
+        expect(signature_header).to eq build_signature_string(actor_keypair, 'https://remote.domain/users/bob#main-key', 'get /activitypub/success', { 'Date' => 'Wed, 20 Dec 2023 10:00:00 GMT', 'Host' => 'www.example.com' })
+
+        get '/activitypub/success', headers: {
+          'Host' => 'www.example.com',
+          'Date' => 'Wed, 20 Dec 2023 10:00:00 GMT',
+          'Signature' => signature_header,
+        }
+
+        expect(response).to have_http_status(200)
+        expect(body_as_json).to match(
+          signed_request: true,
+          signature_actor_id: actor.id.to_s
+        )
+      end
+    end
+
+    context 'with a valid signature on a GET request that has a query string' do
+      let(:signature_header) do
+        'keyId="https://remote.domain/users/bob#main-key",algorithm="rsa-sha256",headers="date host (request-target)",signature="SDMa4r/DQYMXYxVgYO2yEqGWWUXugKjVuz0I8dniQAk+aunzBaF2aPu+4grBfawAshlx1Xytl8lhb0H2MllEz16/tKY7rUrb70MK0w8ohXgpb0qs3YvQgdj4X24L1x2MnkFfKHR/J+7TBlnivq0HZqXm8EIkPWLv+eQxu8fbowLwHIVvRd/3t6FzvcfsE0UZKkoMEX02542MhwSif6cu7Ec/clsY9qgKahb9JVGOGS1op9Lvg/9y1mc8KCgD83U5IxVygYeYXaVQ6gixA9NgZiTCwEWzHM5ELm7w5hpdLFYxYOHg/3G3fiqJzpzNQAcCD4S4JxfE7hMI0IzVlNLT6A=="' # rubocop:disable Layout/LineLength
+      end
+
+      it 'successfuly verifies signature', :aggregate_failures do
+        expect(signature_header).to eq build_signature_string(actor_keypair, 'https://remote.domain/users/bob#main-key', 'get /activitypub/success?foo=42', { 'Date' => 'Wed, 20 Dec 2023 10:00:00 GMT', 'Host' => 'www.example.com' })
+
+        get '/activitypub/success?foo=42', headers: {
+          'Host' => 'www.example.com',
+          'Date' => 'Wed, 20 Dec 2023 10:00:00 GMT',
+          'Signature' => signature_header,
+        }
+
+        expect(response).to have_http_status(200)
+        expect(body_as_json).to match(
+          signed_request: true,
+          signature_actor_id: actor.id.to_s
+        )
+      end
+    end
+
+    context 'when the query string is missing from the signature verification (compatibility quirk)' do
+      let(:signature_header) do
+        'keyId="https://remote.domain/users/bob#main-key",algorithm="rsa-sha256",headers="date host (request-target)",signature="Z8ilar3J7bOwqZkMp7sL8sRs4B1FT+UorbmvWoE+A5UeoOJ3KBcUmbsh+k3wQwbP5gMNUrra9rEWabpasZGphLsbDxfbsWL3Cf0PllAc7c1c7AFEwnewtExI83/qqgEkfWc2z7UDutXc2NfgAx89Ox8DXU/fA2GG0jILjB6UpFyNugkY9rg6oI31UnvfVi3R7sr3/x8Ea3I9thPvqI2byF6cojknSpDAwYzeKdngX3TAQEGzFHz3SDWwyp3jeMWfwvVVbM38FxhvAnSumw7YwWW4L7M7h4M68isLimoT3yfCn2ucBVL5Dz8koBpYf/40w7QidClAwCafZQFC29yDOg=="' # rubocop:disable Layout/LineLength
+      end
+
+      it 'successfuly verifies signature', :aggregate_failures do
+        expect(signature_header).to eq build_signature_string(actor_keypair, 'https://remote.domain/users/bob#main-key', 'get /activitypub/success', { 'Date' => 'Wed, 20 Dec 2023 10:00:00 GMT', 'Host' => 'www.example.com' })
+
+        get '/activitypub/success?foo=42', headers: {
+          'Host' => 'www.example.com',
+          'Date' => 'Wed, 20 Dec 2023 10:00:00 GMT',
+          'Signature' => signature_header,
+        }
+
+        expect(response).to have_http_status(200)
+        expect(body_as_json).to match(
+          signed_request: true,
+          signature_actor_id: actor.id.to_s
+        )
+      end
+    end
+
+    context 'with mismatching query string' do
+      let(:signature_header) do
+        'keyId="https://remote.domain/users/bob#main-key",algorithm="rsa-sha256",headers="date host (request-target)",signature="SDMa4r/DQYMXYxVgYO2yEqGWWUXugKjVuz0I8dniQAk+aunzBaF2aPu+4grBfawAshlx1Xytl8lhb0H2MllEz16/tKY7rUrb70MK0w8ohXgpb0qs3YvQgdj4X24L1x2MnkFfKHR/J+7TBlnivq0HZqXm8EIkPWLv+eQxu8fbowLwHIVvRd/3t6FzvcfsE0UZKkoMEX02542MhwSif6cu7Ec/clsY9qgKahb9JVGOGS1op9Lvg/9y1mc8KCgD83U5IxVygYeYXaVQ6gixA9NgZiTCwEWzHM5ELm7w5hpdLFYxYOHg/3G3fiqJzpzNQAcCD4S4JxfE7hMI0IzVlNLT6A=="' # rubocop:disable Layout/LineLength
+      end
+
+      it 'fails to verify signature', :aggregate_failures do
+        expect(signature_header).to eq build_signature_string(actor_keypair, 'https://remote.domain/users/bob#main-key', 'get /activitypub/success?foo=42', { 'Date' => 'Wed, 20 Dec 2023 10:00:00 GMT', 'Host' => 'www.example.com' })
+
+        get '/activitypub/success?foo=43', headers: {
+          'Host' => 'www.example.com',
+          'Date' => 'Wed, 20 Dec 2023 10:00:00 GMT',
+          'Signature' => signature_header,
+        }
+
+        expect(body_as_json).to match(
+          signed_request: true,
+          signature_actor_id: nil,
+          error: anything
+        )
+      end
+    end
+
+    context 'with a mismatching path' do
+      it 'fails to verify signature', :aggregate_failures do
+        get '/activitypub/alternative-path', headers: {
+          'Host' => 'www.example.com',
+          'Date' => 'Wed, 20 Dec 2023 10:00:00 GMT',
+          'Signature' => 'keyId="https://remote.domain/users/bob#main-key",algorithm="rsa-sha256",headers="date host (request-target)",signature="Z8ilar3J7bOwqZkMp7sL8sRs4B1FT+UorbmvWoE+A5UeoOJ3KBcUmbsh+k3wQwbP5gMNUrra9rEWabpasZGphLsbDxfbsWL3Cf0PllAc7c1c7AFEwnewtExI83/qqgEkfWc2z7UDutXc2NfgAx89Ox8DXU/fA2GG0jILjB6UpFyNugkY9rg6oI31UnvfVi3R7sr3/x8Ea3I9thPvqI2byF6cojknSpDAwYzeKdngX3TAQEGzFHz3SDWwyp3jeMWfwvVVbM38FxhvAnSumw7YwWW4L7M7h4M68isLimoT3yfCn2ucBVL5Dz8koBpYf/40w7QidClAwCafZQFC29yDOg=="', # rubocop:disable Layout/LineLength
+        }
+
+        expect(body_as_json).to match(
+          signed_request: true,
+          signature_actor_id: nil,
+          error: anything
+        )
+      end
+    end
+
+    context 'with a mismatching method' do
+      it 'fails to verify signature', :aggregate_failures do
+        post '/activitypub/success', headers: {
+          'Host' => 'www.example.com',
+          'Date' => 'Wed, 20 Dec 2023 10:00:00 GMT',
+          'Signature' => 'keyId="https://remote.domain/users/bob#main-key",algorithm="rsa-sha256",headers="date host (request-target)",signature="Z8ilar3J7bOwqZkMp7sL8sRs4B1FT+UorbmvWoE+A5UeoOJ3KBcUmbsh+k3wQwbP5gMNUrra9rEWabpasZGphLsbDxfbsWL3Cf0PllAc7c1c7AFEwnewtExI83/qqgEkfWc2z7UDutXc2NfgAx89Ox8DXU/fA2GG0jILjB6UpFyNugkY9rg6oI31UnvfVi3R7sr3/x8Ea3I9thPvqI2byF6cojknSpDAwYzeKdngX3TAQEGzFHz3SDWwyp3jeMWfwvVVbM38FxhvAnSumw7YwWW4L7M7h4M68isLimoT3yfCn2ucBVL5Dz8koBpYf/40w7QidClAwCafZQFC29yDOg=="', # rubocop:disable Layout/LineLength
+        }
+
+        expect(body_as_json).to match(
+          signed_request: true,
+          signature_actor_id: nil,
+          error: anything
+        )
+      end
+    end
+
+    context 'with an unparsable date' do
+      let(:signature_header) do
+        'keyId="https://remote.domain/users/bob#main-key",algorithm="rsa-sha256",headers="date host (request-target)",signature="d4B7nfx8RJcfdJDu1J//5WzPzK/hgtPkdzZx49lu5QhnE7qdV3lgyVimmhCFrO16bwvzIp9iRMyRLkNFxLiEeVaa1gqeKbldGSnU0B0OMjx7rFBa65vLuzWQOATDitVGiBEYqoK4v0DMuFCz2DtFaA/DIUZ3sty8bZ/Ea3U1nByLOO6MacARA3zhMSI0GNxGqsSmZmG0hPLavB3jIXoE3IDoQabMnC39jrlcO/a8h1iaxBm2WD8TejrImJullgqlJIFpKhIHI3ipQkvTGPlm9dx0y+beM06qBvWaWQcmT09eRIUefVsOAzIhUtS/7FVb/URhZvircIJDa7vtiFcmZQ=="' # rubocop:disable Layout/LineLength
+      end
+
+      it 'fails to verify signature', :aggregate_failures do
+        expect(signature_header).to eq build_signature_string(actor_keypair, 'https://remote.domain/users/bob#main-key', 'get /activitypub/success', { 'Date' => 'wrong date', 'Host' => 'www.example.com' })
+
+        get '/activitypub/success', headers: {
+          'Host' => 'www.example.com',
+          'Date' => 'wrong date',
+          'Signature' => signature_header,
+        }
+
+        expect(body_as_json).to match(
+          signed_request: true,
+          signature_actor_id: nil,
+          error: 'Invalid Date header: not RFC 2616 compliant date: "wrong date"'
+        )
+      end
+    end
+
+    context 'with a request older than a day' do
+      let(:signature_header) do
+        'keyId="https://remote.domain/users/bob#main-key",algorithm="rsa-sha256",headers="date host (request-target)",signature="G1NuJv4zgoZ3B/ZIjzDWZHK4RC+5pYee74q8/LJEMCWXhcnAomcb9YHaqk1QYfQvcBUIXw3UZ3Q9xO8F9y0i8G5mzJHfQ+OgHqCoJk8EmGwsUXJMh5s1S5YFCRt8TT12TmJZz0VMqLq85ubueSYBM7QtUE/FzFIVLvz4RysgXxaXQKzdnM6+gbUEEKdCURpXdQt2NXQhp4MAmZH3+0lQoR6VxdsK0hx0Ji2PNp1nuqFTlYqNWZazVdLBN+9rETLRmvGXknvg9jOxTTppBVWnkAIl26HtLS3wwFVvz4pJzi9OQDOvLziehVyLNbU61hky+oJ215e2HuKSe2hxHNl1MA=="' # rubocop:disable Layout/LineLength
+      end
+
+      it 'fails to verify signature', :aggregate_failures do
+        expect(signature_header).to eq build_signature_string(actor_keypair, 'https://remote.domain/users/bob#main-key', 'get /activitypub/success', { 'Date' => 'Wed, 18 Dec 2023 10:00:00 GMT', 'Host' => 'www.example.com' })
+
+        get '/activitypub/success', headers: {
+          'Host' => 'www.example.com',
+          'Date' => 'Wed, 18 Dec 2023 10:00:00 GMT',
+          'Signature' => signature_header,
+        }
+
+        expect(body_as_json).to match(
+          signed_request: true,
+          signature_actor_id: nil,
+          error: 'Signed request date outside acceptable time window'
+        )
+      end
+    end
+
+    context 'with a valid signature on a POST request' do
+      let(:digest_header) { 'SHA-256=ZOyIygCyaOW6GjVnihtTFtIS9PNmskdyMlNKiuyjfzw=' }
+      let(:signature_header) do
+        'keyId="https://remote.domain/users/bob#main-key",algorithm="rsa-sha256",headers="host date digest (request-target)",signature="gmhMjgMROGElJU3fpehV2acD5kMHeELi8EFP2UPHOdQ54H0r55AxIpji+J3lPe+N2qSb/4H1KXIh6f0lRu8TGSsu12OQmg5hiO8VA9flcA/mh9Lpk+qwlQZIPRqKP9xUEfqD+Z7ti5wPzDKrWAUK/7FIqWgcT/mlqB1R1MGkpMFc/q4CIs2OSNiWgA4K+Kp21oQxzC2kUuYob04gAZ7cyE/FTia5t08uv6lVYFdRsn4XNPn1MsHgFBwBMRG79ng3SyhoG4PrqBEi5q2IdLq3zfre/M6He3wlCpyO2VJNdGVoTIzeZ0Zz8jUscPV3XtWUchpGclLGSaKaq/JyNZeiYQ=="' # rubocop:disable Layout/LineLength
+      end
+
+      it 'successfuly verifies signature', :aggregate_failures do
+        expect(digest_header).to eq digest_value('Hello world')
+        expect(signature_header).to eq build_signature_string(actor_keypair, 'https://remote.domain/users/bob#main-key', 'post /activitypub/success', { 'Host' => 'www.example.com', 'Date' => 'Wed, 20 Dec 2023 10:00:00 GMT', 'Digest' => digest_header })
+
+        post '/activitypub/success', params: 'Hello world', headers: {
+          'Host' => 'www.example.com',
+          'Date' => 'Wed, 20 Dec 2023 10:00:00 GMT',
+          'Digest' => digest_header,
+          'Signature' => signature_header,
+        }
+
+        expect(response).to have_http_status(200)
+        expect(body_as_json).to match(
+          signed_request: true,
+          signature_actor_id: actor.id.to_s
+        )
+      end
+    end
+
+    context 'when the Digest of a POST request is not signed' do
+      let(:digest_header) { 'SHA-256=ZOyIygCyaOW6GjVnihtTFtIS9PNmskdyMlNKiuyjfzw=' }
+      let(:signature_header) do
+        'keyId="https://remote.domain/users/bob#main-key",algorithm="rsa-sha256",headers="host date (request-target)",signature="CPD704CG8aCm8X8qIP8kkkiGp1qwFLk/wMVQHOGP0Txxan8c2DZtg/KK7eN8RG8tHx8br/yS2hJs51x4kXImYukGzNJd7ihE3T8lp+9RI1tCcdobTzr/VcVJHDFySdQkg266GCMijRQRZfNvqlJLiisr817PI+gNVBI5qV+vnVd1XhWCEZ+YSmMe8UqYARXAYNqMykTheojqGpTeTFGPUpTQA2Fmt2BipwIjcFDm2Hpihl2kB0MUS0x3zPmHDuadvzoBbN6m3usPDLgYrpALlh+wDs1dYMntcwdwawRKY1oE1XNtgOSum12wntDq3uYL4gya2iPdcw3c929b4koUzw=="' # rubocop:disable Layout/LineLength
+      end
+
+      it 'fails to verify signature', :aggregate_failures do
+        expect(digest_header).to eq digest_value('Hello world')
+        expect(signature_header).to eq build_signature_string(actor_keypair, 'https://remote.domain/users/bob#main-key', 'post /activitypub/success', { 'Host' => 'www.example.com', 'Date' => 'Wed, 20 Dec 2023 10:00:00 GMT' })
+
+        post '/activitypub/success', params: 'Hello world', headers: {
+          'Host' => 'www.example.com',
+          'Date' => 'Wed, 20 Dec 2023 10:00:00 GMT',
+          'Digest' => digest_header,
+          'Signature' => signature_header,
+        }
+
+        expect(body_as_json).to match(
+          signed_request: true,
+          signature_actor_id: nil,
+          error: 'Mastodon requires the Digest header to be signed when doing a POST request'
+        )
+      end
+    end
+
+    context 'with a tampered body on a POST request' do
+      let(:digest_header) { 'SHA-256=ZOyIygCyaOW6GjVnihtTFtIS9PNmskdyMlNKiuyjfzw=' }
+      let(:signature_header) do
+        'keyId="https://remote.domain/users/bob#main-key",algorithm="rsa-sha256",headers="host date digest (request-target)",signature="gmhMjgMROGElJU3fpehV2acD5kMHeELi8EFP2UPHOdQ54H0r55AxIpji+J3lPe+N2qSb/4H1KXIh6f0lRu8TGSsu12OQmg5hiO8VA9flcA/mh9Lpk+qwlQZIPRqKP9xUEfqD+Z7ti5wPzDKrWAUK/7FIqWgcT/mlqB1R1MGkpMFc/q4CIs2OSNiWgA4K+Kp21oQxzC2kUuYob04gAZ7cyE/FTia5t08uv6lVYFdRsn4XNPn1MsHgFBwBMRG79ng3SyhoG4PrqBEi5q2IdLq3zfre/M6He3wlCpyO2VJNdGVoTIzeZ0Zz8jUscPV3XtWUchpGclLGSaKaq/JyNZeiYQ=="' # rubocop:disable Layout/LineLength
+      end
+
+      it 'fails to verify signature', :aggregate_failures do
+        expect(digest_header).to_not eq digest_value('Hello world!')
+        expect(signature_header).to eq build_signature_string(actor_keypair, 'https://remote.domain/users/bob#main-key', 'post /activitypub/success', { 'Host' => 'www.example.com', 'Date' => 'Wed, 20 Dec 2023 10:00:00 GMT', 'Digest' => digest_header })
+
+        post '/activitypub/success', params: 'Hello world!', headers: {
+          'Host' => 'www.example.com',
+          'Date' => 'Wed, 20 Dec 2023 10:00:00 GMT',
+          'Digest' => 'SHA-256=ZOyIygCyaOW6GjVnihtTFtIS9PNmskdyMlNKiuyjfzw=',
+          'Signature' => signature_header,
+        }
+
+        expect(body_as_json).to match(
+          signed_request: true,
+          signature_actor_id: nil,
+          error: 'Invalid Digest value. Computed SHA-256 digest: wFNeS+K3n/2TKRMFQ2v4iTFOSj+uwF7P/Lt98xrZ5Ro=; given: ZOyIygCyaOW6GjVnihtTFtIS9PNmskdyMlNKiuyjfzw='
+        )
+      end
+    end
+
+    context 'with a tampered path in a POST request' do
+      it 'fails to verify signature', :aggregate_failures do
+        post '/activitypub/alternative-path', params: 'Hello world', headers: {
+          'Host' => 'www.example.com',
+          'Date' => 'Wed, 20 Dec 2023 10:00:00 GMT',
+          'Digest' => 'SHA-256=ZOyIygCyaOW6GjVnihtTFtIS9PNmskdyMlNKiuyjfzw=',
+          'Signature' => 'keyId="https://remote.domain/users/bob#main-key",algorithm="rsa-sha256",headers="host date digest (request-target)",signature="gmhMjgMROGElJU3fpehV2acD5kMHeELi8EFP2UPHOdQ54H0r55AxIpji+J3lPe+N2qSb/4H1KXIh6f0lRu8TGSsu12OQmg5hiO8VA9flcA/mh9Lpk+qwlQZIPRqKP9xUEfqD+Z7ti5wPzDKrWAUK/7FIqWgcT/mlqB1R1MGkpMFc/q4CIs2OSNiWgA4K+Kp21oQxzC2kUuYob04gAZ7cyE/FTia5t08uv6lVYFdRsn4XNPn1MsHgFBwBMRG79ng3SyhoG4PrqBEi5q2IdLq3zfre/M6He3wlCpyO2VJNdGVoTIzeZ0Zz8jUscPV3XtWUchpGclLGSaKaq/JyNZeiYQ=="', # rubocop:disable Layout/LineLength
+        }
+
+        expect(response).to have_http_status(200)
+        expect(body_as_json).to match(
+          signed_request: true,
+          signature_actor_id: nil,
+          error: anything
+        )
+      end
+    end
+  end
+
+  context 'with an inaccessible key' do
+    before do
+      stub_request(:get, 'https://remote.domain/users/alice#main-key').to_return(status: 404)
+    end
+
+    it 'fails to verify signature', :aggregate_failures do
+      get '/activitypub/success', headers: {
+        'Host' => 'www.example.com',
+        'Date' => 'Wed, 20 Dec 2023 10:00:00 GMT',
+        'Signature' => 'keyId="https://remote.domain/users/alice#main-key",algorithm="rsa-sha256",headers="date host (request-target)",signature="Z8ilar3J7bOwqZkMp7sL8sRs4B1FT+UorbmvWoE+A5UeoOJ3KBcUmbsh+k3wQwbP5gMNUrra9rEWabpasZGphLsbDxfbsWL3Cf0PllAc7c1c7AFEwnewtExI83/qqgEkfWc2z7UDutXc2NfgAx89Ox8DXU/fA2GG0jILjB6UpFyNugkY9rg6oI31UnvfVi3R7sr3/x8Ea3I9thPvqI2byF6cojknSpDAwYzeKdngX3TAQEGzFHz3SDWwyp3jeMWfwvVVbM38FxhvAnSumw7YwWW4L7M7h4M68isLimoT3yfCn2ucBVL5Dz8koBpYf/40w7QidClAwCafZQFC29yDOg=="', # rubocop:disable Layout/LineLength
+      }
+
+      expect(body_as_json).to match(
+        signed_request: true,
+        signature_actor_id: nil,
+        error: 'Unable to fetch key JSON at https://remote.domain/users/alice#main-key'
+      )
+    end
+  end
+
+  private
+
+  def stub_tests_controller
+    stub_const('ActivityPub::TestsController', activitypub_tests_controller)
+
+    Rails.application.routes.draw do
+      # NOTE: RouteSet#draw removes all routes, so we need to re-insert one
+      resource :instance_actor, path: 'actor', only: [:show]
+
+      match :via => [:get, :post], '/activitypub/success' => 'activitypub/tests#success'
+      match :via => [:get, :post], '/activitypub/alternative-path' => 'activitypub/tests#alternative_success'
+      match :via => [:get, :post], '/activitypub/signature_required' => 'activitypub/tests#signature_required'
+    end
+  end
+
+  def activitypub_tests_controller
+    Class.new(ApplicationController) do
+      include SignatureVerification
+
+      before_action :require_actor_signature!, only: [:signature_required]
+
+      def success
+        render json: {
+          signed_request: signed_request?,
+          signature_actor_id: signed_request_actor&.id&.to_s,
+        }.merge(signature_verification_failure_reason || {})
+      end
+
+      alias_method :alternative_success, :success
+      alias_method :signature_required, :success
+    end
+  end
+
+  def digest_value(body)
+    "SHA-256=#{Digest::SHA256.base64digest(body)}"
+  end
+
+  def build_signature_string(keypair, key_id, request_target, headers)
+    algorithm = 'rsa-sha256'
+    signed_headers = headers.merge({ '(request-target)' => request_target })
+    signed_string = signed_headers.map { |key, value| "#{key.downcase}: #{value}" }.join("\n")
+    signature = Base64.strict_encode64(keypair.sign(OpenSSL::Digest.new('SHA256'), signed_string))
+
+    "keyId=\"#{key_id}\",algorithm=\"#{algorithm}\",headers=\"#{signed_headers.keys.join(' ').downcase}\",signature=\"#{signature}\""
+  end
+end

spec/services/activitypub/fetch_featured_collection_service_spec.rb

@@ -60,10 +60,10 @@ RSpec.describe ActivityPub::FetchFeaturedCollectionService, type: :service do
 
   shared_examples 'sets pinned posts' do
     before do
-      stub_request(:get, 'https://example.com/account/pinned/1').to_return(status: 200, body: Oj.dump(status_json_1))
-      stub_request(:get, 'https://example.com/account/pinned/2').to_return(status: 200, body: Oj.dump(status_json_2))
+      stub_request(:get, 'https://example.com/account/pinned/1').to_return(status: 200, body: Oj.dump(status_json_1), headers: { 'Content-Type': 'application/activity+json' })
+      stub_request(:get, 'https://example.com/account/pinned/2').to_return(status: 200, body: Oj.dump(status_json_2), headers: { 'Content-Type': 'application/activity+json' })
       stub_request(:get, 'https://example.com/account/pinned/3').to_return(status: 404)
-      stub_request(:get, 'https://example.com/account/pinned/4').to_return(status: 200, body: Oj.dump(status_json_4))
+      stub_request(:get, 'https://example.com/account/pinned/4').to_return(status: 200, body: Oj.dump(status_json_4), headers: { 'Content-Type': 'application/activity+json' })
 
       subject.call(actor, note: true, hashtag: false)
     end
@@ -76,7 +76,7 @@ RSpec.describe ActivityPub::FetchFeaturedCollectionService, type: :service do
   describe '#call' do
     context 'when the endpoint is a Collection' do
       before do
-        stub_request(:get, actor.featured_collection_url).to_return(status: 200, body: Oj.dump(payload))
+        stub_request(:get, actor.featured_collection_url).to_return(status: 200, body: Oj.dump(payload), headers: { 'Content-Type': 'application/activity+json' })
       end
 
       it_behaves_like 'sets pinned posts'
@@ -93,10 +93,25 @@ RSpec.describe ActivityPub::FetchFeaturedCollectionService, type: :service do
       end
 
       before do
-        stub_request(:get, actor.featured_collection_url).to_return(status: 200, body: Oj.dump(payload))
+        stub_request(:get, actor.featured_collection_url).to_return(status: 200, body: Oj.dump(payload), headers: { 'Content-Type': 'application/activity+json' })
       end
 
       it_behaves_like 'sets pinned posts'
+
+      context 'when there is a single item, with the array compacted away' do
+        let(:items) { 'https://example.com/account/pinned/4' }
+
+        before do
+          stub_request(:get, 'https://example.com/account/pinned/4').to_return(status: 200, body: Oj.dump(status_json_4), headers: { 'Content-Type': 'application/activity+json' })
+          subject.call(actor, note: true, hashtag: false)
+        end
+
+        it 'sets expected posts as pinned posts' do
+          expect(actor.pinned_statuses.pluck(:uri)).to contain_exactly(
+            'https://example.com/account/pinned/4'
+          )
+        end
+      end
     end
 
     context 'when the endpoint is a paginated Collection' do
@@ -114,10 +129,25 @@ RSpec.describe ActivityPub::FetchFeaturedCollectionService, type: :service do
       end
 
       before do
-        stub_request(:get, actor.featured_collection_url).to_return(status: 200, body: Oj.dump(payload))
+        stub_request(:get, actor.featured_collection_url).to_return(status: 200, body: Oj.dump(payload), headers: { 'Content-Type': 'application/activity+json' })
       end
 
       it_behaves_like 'sets pinned posts'
+
+      context 'when there is a single item, with the array compacted away' do
+        let(:items) { 'https://example.com/account/pinned/4' }
+
+        before do
+          stub_request(:get, 'https://example.com/account/pinned/4').to_return(status: 200, body: Oj.dump(status_json_4), headers: { 'Content-Type': 'application/activity+json' })
+          subject.call(actor, note: true, hashtag: false)
+        end
+
+        it 'sets expected posts as pinned posts' do
+          expect(actor.pinned_statuses.pluck(:uri)).to contain_exactly(
+            'https://example.com/account/pinned/4'
+          )
+        end
+      end
     end
   end
 end

spec/services/activitypub/fetch_featured_tags_collection_service_spec.rb

@@ -36,7 +36,7 @@ RSpec.describe ActivityPub::FetchFeaturedTagsCollectionService, type: :service d
   describe '#call' do
     context 'when the endpoint is a Collection' do
       before do
-        stub_request(:get, collection_url).to_return(status: 200, body: Oj.dump(payload))
+        stub_request(:get, collection_url).to_return(status: 200, body: Oj.dump(payload), headers: { 'Content-Type': 'application/activity+json' })
       end
 
       it_behaves_like 'sets featured tags'
@@ -44,7 +44,7 @@ RSpec.describe ActivityPub::FetchFeaturedTagsCollectionService, type: :service d
 
     context 'when the account already has featured tags' do
       before do
-        stub_request(:get, collection_url).to_return(status: 200, body: Oj.dump(payload))
+        stub_request(:get, collection_url).to_return(status: 200, body: Oj.dump(payload), headers: { 'Content-Type': 'application/activity+json' })
 
         actor.featured_tags.create!(name: 'FoO')
         actor.featured_tags.create!(name: 'baz')
@@ -65,7 +65,7 @@ RSpec.describe ActivityPub::FetchFeaturedTagsCollectionService, type: :service d
       end
 
       before do
-        stub_request(:get, collection_url).to_return(status: 200, body: Oj.dump(payload))
+        stub_request(:get, collection_url).to_return(status: 200, body: Oj.dump(payload), headers: { 'Content-Type': 'application/activity+json' })
       end
 
       it_behaves_like 'sets featured tags'
@@ -86,7 +86,7 @@ RSpec.describe ActivityPub::FetchFeaturedTagsCollectionService, type: :service d
       end
 
       before do
-        stub_request(:get, collection_url).to_return(status: 200, body: Oj.dump(payload))
+        stub_request(:get, collection_url).to_return(status: 200, body: Oj.dump(payload), headers: { 'Content-Type': 'application/activity+json' })
       end
 
       it_behaves_like 'sets featured tags'

spec/services/activitypub/fetch_remote_account_service_spec.rb

@@ -16,7 +16,7 @@ RSpec.describe ActivityPub::FetchRemoteAccountService, type: :service do
   end
 
   describe '#call' do
-    let(:account) { subject.call('https://example.com/alice', id: true) }
+    let(:account) { subject.call('https://example.com/alice') }
 
     shared_examples 'sets profile data' do
       it 'returns an account' do
@@ -42,7 +42,7 @@ RSpec.describe ActivityPub::FetchRemoteAccountService, type: :service do
       before do
         actor[:inbox] = nil
 
-        stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor))
+        stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor), headers: { 'Content-Type': 'application/activity+json' })
         stub_request(:get, 'https://example.com/.well-known/webfinger?resource=acct:alice@example.com').to_return(body: Oj.dump(webfinger), headers: { 'Content-Type': 'application/jrd+json' })
       end
 
@@ -65,7 +65,7 @@ RSpec.describe ActivityPub::FetchRemoteAccountService, type: :service do
       let!(:webfinger) { { subject: 'acct:alice@example.com', links: [{ rel: 'self', href: 'https://example.com/alice' }] } }
 
       before do
-        stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor))
+        stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor), headers: { 'Content-Type': 'application/activity+json' })
         stub_request(:get, 'https://example.com/.well-known/webfinger?resource=acct:alice@example.com').to_return(body: Oj.dump(webfinger), headers: { 'Content-Type': 'application/jrd+json' })
       end
 
@@ -91,7 +91,7 @@ RSpec.describe ActivityPub::FetchRemoteAccountService, type: :service do
       let!(:webfinger) { { subject: 'acct:alice@iscool.af', links: [{ rel: 'self', href: 'https://example.com/alice' }] } }
 
       before do
-        stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor))
+        stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor), headers: { 'Content-Type': 'application/activity+json' })
         stub_request(:get, 'https://example.com/.well-known/webfinger?resource=acct:alice@example.com').to_return(body: Oj.dump(webfinger), headers: { 'Content-Type': 'application/jrd+json' })
         stub_request(:get, 'https://iscool.af/.well-known/webfinger?resource=acct:alice@iscool.af').to_return(body: Oj.dump(webfinger), headers: { 'Content-Type': 'application/jrd+json' })
       end
@@ -123,7 +123,7 @@ RSpec.describe ActivityPub::FetchRemoteAccountService, type: :service do
       let!(:webfinger) { { subject: 'acct:alice@example.com', links: [{ rel: 'self', href: 'https://example.com/bob' }] } }
 
       before do
-        stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor))
+        stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor), headers: { 'Content-Type': 'application/activity+json' })
         stub_request(:get, 'https://example.com/.well-known/webfinger?resource=acct:alice@example.com').to_return(body: Oj.dump(webfinger), headers: { 'Content-Type': 'application/jrd+json' })
       end
 
@@ -146,7 +146,7 @@ RSpec.describe ActivityPub::FetchRemoteAccountService, type: :service do
       let!(:webfinger) { { subject: 'acct:alice@iscool.af', links: [{ rel: 'self', href: 'https://example.com/bob' }] } }
 
       before do
-        stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor))
+        stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor), headers: { 'Content-Type': 'application/activity+json' })
         stub_request(:get, 'https://example.com/.well-known/webfinger?resource=acct:alice@example.com').to_return(body: Oj.dump(webfinger), headers: { 'Content-Type': 'application/jrd+json' })
         stub_request(:get, 'https://iscool.af/.well-known/webfinger?resource=acct:alice@iscool.af').to_return(body: Oj.dump(webfinger), headers: { 'Content-Type': 'application/jrd+json' })
       end

spec/services/activitypub/fetch_remote_actor_service_spec.rb

@@ -16,7 +16,7 @@ RSpec.describe ActivityPub::FetchRemoteActorService, type: :service do
   end
 
   describe '#call' do
-    let(:account) { subject.call('https://example.com/alice', id: true) }
+    let(:account) { subject.call('https://example.com/alice') }
 
     shared_examples 'sets profile data' do
       it 'returns an account' do
@@ -42,7 +42,7 @@ RSpec.describe ActivityPub::FetchRemoteActorService, type: :service do
       before do
         actor[:inbox] = nil
 
-        stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor))
+        stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor), headers: { 'Content-Type': 'application/activity+json' })
         stub_request(:get, 'https://example.com/.well-known/webfinger?resource=acct:alice@example.com').to_return(body: Oj.dump(webfinger), headers: { 'Content-Type': 'application/jrd+json' })
       end
 
@@ -65,7 +65,7 @@ RSpec.describe ActivityPub::FetchRemoteActorService, type: :service do
       let!(:webfinger) { { subject: 'acct:alice@example.com', links: [{ rel: 'self', href: 'https://example.com/alice' }] } }
 
       before do
-        stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor))
+        stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor), headers: { 'Content-Type': 'application/activity+json' })
         stub_request(:get, 'https://example.com/.well-known/webfinger?resource=acct:alice@example.com').to_return(body: Oj.dump(webfinger), headers: { 'Content-Type': 'application/jrd+json' })
       end
 
@@ -91,7 +91,7 @@ RSpec.describe ActivityPub::FetchRemoteActorService, type: :service do
       let!(:webfinger) { { subject: 'acct:alice@iscool.af', links: [{ rel: 'self', href: 'https://example.com/alice' }] } }
 
       before do
-        stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor))
+        stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor), headers: { 'Content-Type': 'application/activity+json' })
         stub_request(:get, 'https://example.com/.well-known/webfinger?resource=acct:alice@example.com').to_return(body: Oj.dump(webfinger), headers: { 'Content-Type': 'application/jrd+json' })
         stub_request(:get, 'https://iscool.af/.well-known/webfinger?resource=acct:alice@iscool.af').to_return(body: Oj.dump(webfinger), headers: { 'Content-Type': 'application/jrd+json' })
       end
@@ -123,7 +123,7 @@ RSpec.describe ActivityPub::FetchRemoteActorService, type: :service do
       let!(:webfinger) { { subject: 'acct:alice@example.com', links: [{ rel: 'self', href: 'https://example.com/bob' }] } }
 
       before do
-        stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor))
+        stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor), headers: { 'Content-Type': 'application/activity+json' })
         stub_request(:get, 'https://example.com/.well-known/webfinger?resource=acct:alice@example.com').to_return(body: Oj.dump(webfinger), headers: { 'Content-Type': 'application/jrd+json' })
       end
 
@@ -146,7 +146,7 @@ RSpec.describe ActivityPub::FetchRemoteActorService, type: :service do
       let!(:webfinger) { { subject: 'acct:alice@iscool.af', links: [{ rel: 'self', href: 'https://example.com/bob' }] } }
 
       before do
-        stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor))
+        stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor), headers: { 'Content-Type': 'application/activity+json' })
         stub_request(:get, 'https://example.com/.well-known/webfinger?resource=acct:alice@example.com').to_return(body: Oj.dump(webfinger), headers: { 'Content-Type': 'application/jrd+json' })
         stub_request(:get, 'https://iscool.af/.well-known/webfinger?resource=acct:alice@iscool.af').to_return(body: Oj.dump(webfinger), headers: { 'Content-Type': 'application/jrd+json' })
       end

spec/services/activitypub/fetch_remote_key_service_spec.rb

@@ -38,16 +38,16 @@ RSpec.describe ActivityPub::FetchRemoteKeyService, type: :service do
   end
 
   before do
-    stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor))
+    stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor), headers: { 'Content-Type': 'application/activity+json' })
     stub_request(:get, 'https://example.com/.well-known/webfinger?resource=acct:alice@example.com').to_return(body: Oj.dump(webfinger), headers: { 'Content-Type': 'application/jrd+json' })
   end
 
   describe '#call' do
-    let(:account) { subject.call(public_key_id, id: false) }
+    let(:account) { subject.call(public_key_id) }
 
     context 'when the key is a sub-object from the actor' do
       before do
-        stub_request(:get, public_key_id).to_return(body: Oj.dump(actor))
+        stub_request(:get, public_key_id).to_return(body: Oj.dump(actor), headers: { 'Content-Type': 'application/activity+json' })
       end
 
       it 'returns the expected account' do
@@ -59,7 +59,7 @@ RSpec.describe ActivityPub::FetchRemoteKeyService, type: :service do
       let(:public_key_id) { 'https://example.com/alice-public-key.json' }
 
       before do
-        stub_request(:get, public_key_id).to_return(body: Oj.dump(key_json.merge({ '@context': ['https://www.w3.org/ns/activitystreams', 'https://w3id.org/security/v1'] })))
+        stub_request(:get, public_key_id).to_return(body: Oj.dump(key_json.merge({ '@context': ['https://www.w3.org/ns/activitystreams', 'https://w3id.org/security/v1'] })), headers: { 'Content-Type': 'application/activity+json' })
       end
 
       it 'returns the expected account' do
@@ -72,7 +72,7 @@ RSpec.describe ActivityPub::FetchRemoteKeyService, type: :service do
       let(:actor_public_key) { 'https://example.com/alice-public-key.json' }
 
       before do
-        stub_request(:get, public_key_id).to_return(body: Oj.dump(key_json.merge({ '@context': ['https://www.w3.org/ns/activitystreams', 'https://w3id.org/security/v1'] })))
+        stub_request(:get, public_key_id).to_return(body: Oj.dump(key_json.merge({ '@context': ['https://www.w3.org/ns/activitystreams', 'https://w3id.org/security/v1'] })), headers: { 'Content-Type': 'application/activity+json' })
       end
 
       it 'returns the nil' do

spec/services/activitypub/fetch_replies_service_spec.rb

@@ -32,6 +32,18 @@ RSpec.describe ActivityPub::FetchRepliesService, type: :service do
 
   describe '#call' do
     context 'when the payload is a Collection with inlined replies' do
+      context 'when there is a single reply, with the array compacted away' do
+        let(:items) { 'http://example.com/self-reply-1' }
+
+        it 'queues the expected worker' do
+          allow(FetchReplyWorker).to receive(:push_bulk)
+
+          subject.call(status, payload)
+
+          expect(FetchReplyWorker).to have_received(:push_bulk).with(['http://example.com/self-reply-1'])
+        end
+      end
+
       context 'when passing the collection itself' do
         it 'spawns workers for up to 5 replies on the same server' do
           expect(FetchReplyWorker).to receive(:push_bulk).with(['http://example.com/self-reply-1', 'http://example.com/self-reply-2', 'http://example.com/self-reply-3', 'http://example.com/self-reply-4', 'http://example.com/self-reply-5'])
@@ -41,7 +53,7 @@ RSpec.describe ActivityPub::FetchRepliesService, type: :service do
 
       context 'when passing the URL to the collection' do
         before do
-          stub_request(:get, collection_uri).to_return(status: 200, body: Oj.dump(payload))
+          stub_request(:get, collection_uri).to_return(status: 200, body: Oj.dump(payload), headers: { 'Content-Type': 'application/activity+json' })
         end
 
         it 'spawns workers for up to 5 replies on the same server' do
@@ -70,7 +82,7 @@ RSpec.describe ActivityPub::FetchRepliesService, type: :service do
 
       context 'when passing the URL to the collection' do
         before do
-          stub_request(:get, collection_uri).to_return(status: 200, body: Oj.dump(payload))
+          stub_request(:get, collection_uri).to_return(status: 200, body: Oj.dump(payload), headers: { 'Content-Type': 'application/activity+json' })
         end
 
         it 'spawns workers for up to 5 replies on the same server' do
@@ -103,7 +115,7 @@ RSpec.describe ActivityPub::FetchRepliesService, type: :service do
 
       context 'when passing the URL to the collection' do
         before do
-          stub_request(:get, collection_uri).to_return(status: 200, body: Oj.dump(payload))
+          stub_request(:get, collection_uri).to_return(status: 200, body: Oj.dump(payload), headers: { 'Content-Type': 'application/activity+json' })
         end
 
         it 'spawns workers for up to 5 replies on the same server' do

spec/services/activitypub/synchronize_followers_service_spec.rb

@@ -58,7 +58,7 @@ RSpec.describe ActivityPub::SynchronizeFollowersService, type: :service do
   describe '#call' do
     context 'when the endpoint is a Collection of actor URIs' do
       before do
-        stub_request(:get, collection_uri).to_return(status: 200, body: Oj.dump(payload))
+        stub_request(:get, collection_uri).to_return(status: 200, body: Oj.dump(payload), headers: { 'Content-Type': 'application/activity+json' })
       end
 
       it_behaves_like 'synchronizes followers'
@@ -75,7 +75,7 @@ RSpec.describe ActivityPub::SynchronizeFollowersService, type: :service do
       end
 
       before do
-        stub_request(:get, collection_uri).to_return(status: 200, body: Oj.dump(payload))
+        stub_request(:get, collection_uri).to_return(status: 200, body: Oj.dump(payload), headers: { 'Content-Type': 'application/activity+json' })
       end
 
       it_behaves_like 'synchronizes followers'
@@ -96,7 +96,7 @@ RSpec.describe ActivityPub::SynchronizeFollowersService, type: :service do
       end
 
       before do
-        stub_request(:get, collection_uri).to_return(status: 200, body: Oj.dump(payload))
+        stub_request(:get, collection_uri).to_return(status: 200, body: Oj.dump(payload), headers: { 'Content-Type': 'application/activity+json' })
       end
 
       it_behaves_like 'synchronizes followers'

spec/services/fetch_resource_service_spec.rb

@@ -54,7 +54,7 @@ RSpec.describe FetchResourceService, type: :service do
 
       let(:json) do
         {
-          id: 1,
+          id: 'http://example.com/foo',
           '@context': ActivityPub::TagManager::CONTEXT,
           type: 'Note',
         }.to_json
@@ -79,14 +79,14 @@ RSpec.describe FetchResourceService, type: :service do
         let(:content_type) { 'application/activity+json; charset=utf-8' }
         let(:body) { json }
 
-        it { is_expected.to eq [1, { prefetched_body: body, id: true }] }
+        it { is_expected.to eq ['http://example.com/foo', { prefetched_body: body }] }
       end
 
       context 'when content type is ld+json with profile' do
         let(:content_type) { 'application/ld+json; profile="https://www.w3.org/ns/activitystreams"' }
         let(:body) { json }
 
-        it { is_expected.to eq [1, { prefetched_body: body, id: true }] }
+        it { is_expected.to eq ['http://example.com/foo', { prefetched_body: body }] }
       end
 
       before do
@@ -97,14 +97,14 @@ RSpec.describe FetchResourceService, type: :service do
       context 'when link header is present' do
         let(:headers) { { 'Link' => '<http://example.com/foo>; rel="alternate"; type="application/activity+json"', } }
 
-        it { is_expected.to eq [1, { prefetched_body: json, id: true }] }
+        it { is_expected.to eq ['http://example.com/foo', { prefetched_body: json }] }
       end
 
       context 'when content type is text/html' do
         let(:content_type) { 'text/html' }
         let(:body) { '<html><head><link rel="alternate" href="http://example.com/foo" type="application/activity+json"/></head></html>' }
 
-        it { is_expected.to eq [1, { prefetched_body: json, id: true }] }
+        it { is_expected.to eq ['http://example.com/foo', { prefetched_body: json }] }
       end
     end
   end

spec/services/reblog_service_spec.rb

@@ -69,9 +69,5 @@ RSpec.describe ReblogService, type: :service do
     it 'distributes to followers' do
       expect(ActivityPub::DistributionWorker).to have_received(:perform_async)
     end
-
-    it 'sends an announce activity to the author' do
-      expect(a_request(:post, bob.inbox_url)).to have_been_made.once
-    end
   end
 end

spec/services/remove_status_service_spec.rb

@@ -108,4 +108,22 @@ RSpec.describe RemoveStatusService, type: :service do
       )).to have_been_made.once
     end
   end
+
+  context 'when removed status is a reblog of a non-follower' do
+    let!(:original_status) { Fabricate(:status, account: bill, text: 'Hello ThisIsASecret', visibility: :public) }
+    let!(:status) { ReblogService.new.call(alice, original_status) }
+
+    it 'sends Undo activity to followers' do
+      subject.call(status)
+      expect(a_request(:post, bill.inbox_url).with(
+               body: hash_including({
+                 'type' => 'Undo',
+                 'object' => hash_including({
+                   'type' => 'Announce',
+                   'object' => ActivityPub::TagManager.instance.uri_for(original_status),
+                 }),
+               })
+             )).to have_been_made.once
+    end
+  end
 end

spec/services/resolve_url_service_spec.rb

@@ -139,6 +139,7 @@ describe ResolveURLService, type: :service do
         stub_request(:get, url).to_return(status: 302, headers: { 'Location' => status_url })
         body = ActiveModelSerializers::SerializableResource.new(status, serializer: ActivityPub::NoteSerializer, adapter: ActivityPub::Adapter).to_json
         stub_request(:get, status_url).to_return(body: body, headers: { 'Content-Type' => 'application/activity+json' })
+        stub_request(:get, uri).to_return(body: body, headers: { 'Content-Type' => 'application/activity+json' })
       end
 
       it 'returns status by url' do

spec/support/omniauth_mocks.rb

@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+
+OmniAuth.config.test_mode = true
+
+def mock_omniauth(provider, data)
+  OmniAuth.config.mock_auth[provider] = OmniAuth::AuthHash.new(data)
+end

spec/workers/activitypub/fetch_replies_worker_spec.rb

@@ -21,7 +21,7 @@ describe ActivityPub::FetchRepliesWorker do
 
   describe 'perform' do
     it 'performs a request if the collection URI is from the same host' do
-      stub_request(:get, 'https://example.com/statuses_replies/1').to_return(status: 200, body: json)
+      stub_request(:get, 'https://example.com/statuses_replies/1').to_return(status: 200, body: json, headers: { 'Content-Type': 'application/activity+json' })
       subject.perform(status.id, 'https://example.com/statuses_replies/1')
       expect(a_request(:get, 'https://example.com/statuses_replies/1')).to have_been_made.once
     end