4 files changed, 63 insertions, 4 deletions
diff --git a/app/services/activitypub/process_account_service.rb b/app/services/activitypub/process_account_service.rb
index 670a0e4d6..c77858f1d 100644
--- a/app/services/activitypub/process_account_service.rb
+++ b/app/services/activitypub/process_account_service.rb
@@ -34,6 +34,7 @@ class ActivityPub::ProcessAccountService < BaseService
     after_protocol_change! if protocol_changed?
     after_key_change! if key_changed? && !@options[:signed_with_known_key]
     check_featured_collection! if @account.featured_collection_url.present?
+    check_links! unless @account.fields.empty?
 
     @account
   rescue Oj::ParseError
@@ -99,6 +100,10 @@ class ActivityPub::ProcessAccountService < BaseService
     ActivityPub::SynchronizeFeaturedCollectionWorker.perform_async(@account.id)
   end
 
+  def check_links!
+    VerifyAccountLinksWorker.perform_async(@account.id)
+  end
+
   def actor_type
     if @json['type'].is_a?(Array)
       @json['type'].find { |type| ActivityPub::FetchRemoteAccountService::SUPPORTED_TYPES.include?(type) }
diff --git a/app/services/fetch_link_card_service.rb b/app/services/fetch_link_card_service.rb
index ea94e2491..4169c685b 100644
--- a/app/services/fetch_link_card_service.rb
+++ b/app/services/fetch_link_card_service.rb
@@ -29,7 +29,7 @@ class FetchLinkCardService < BaseService
     end
 
     attach_card if @card&.persisted?
-  rescue HTTP::Error, Addressable::URI::InvalidURIError, Mastodon::LengthValidationError => e
+  rescue HTTP::Error, Addressable::URI::InvalidURIError, Mastodon::HostValidationError, Mastodon::LengthValidationError => e
     Rails.logger.debug "Error fetching link #{@url}: #{e}"
     nil
   end
diff --git a/app/services/update_account_service.rb b/app/services/update_account_service.rb
index 09ea377e7..ec69d944a 100644
--- a/app/services/update_account_service.rb
+++ b/app/services/update_account_service.rb
@@ -2,20 +2,26 @@
 
 class UpdateAccountService < BaseService
   def call(account, params, raise_error: false)
-    was_locked = account.locked
+    was_locked    = account.locked
     update_method = raise_error ? :update! : :update
+
     account.send(update_method, params).tap do |ret|
       next unless ret
+
       authorize_all_follow_requests(account) if was_locked && !account.locked
+      check_links(account)
     end
   end
 
   private
 
   def authorize_all_follow_requests(account)
-    follow_requests = FollowRequest.where(target_account: account)
-    AuthorizeFollowWorker.push_bulk(follow_requests) do |req|
+    AuthorizeFollowWorker.push_bulk(FollowRequest.where(target_account: account).select(:account_id, :target_account_id)) do |req|
       [req.account_id, req.target_account_id]
     end
   end
+
+  def check_links(account)
+    VerifyAccountLinksWorker.perform_async(account.id)
+  end
 end
diff --git a/app/services/verify_link_service.rb b/app/services/verify_link_service.rb
new file mode 100644
index 000000000..7d53bc255
--- /dev/null
+++ b/app/services/verify_link_service.rb
@@ -0,0 +1,48 @@
+# frozen_string_literal: true
+
+class VerifyLinkService < BaseService
+  def call(field)
+    @link_back = ActivityPub::TagManager.instance.url_for(field.account)
+    @url       = field.value
+
+    perform_request!
+
+    return unless link_back_present?
+
+    field.mark_verified!
+    field.account.save!
+  rescue HTTP::Error, Addressable::URI::InvalidURIError, Mastodon::HostValidationError, Mastodon::LengthValidationError => e
+    Rails.logger.debug "Error fetching link #{@url}: #{e}"
+    nil
+  end
+
+  private
+
+  def perform_request!
+    @body = Request.new(:get, @url).add_headers('Accept' => 'text/html').perform do |res|
+      res.code != 200 ? nil : res.body_with_limit
+    end
+  end
+
+  def link_back_present?
+    return false if @body.empty?
+
+    links = Nokogiri::HTML(@body).xpath('//a[contains(concat(" ", normalize-space(@rel), " "), " me ")]|//link[contains(concat(" ", normalize-space(@rel), " "), " me ")]')
+
+    if links.any? { |link| link['href'] == @link_back }
+      true
+    elsif links.empty?
+      false
+    else
+      link_redirects_back?(links.first['href'])
+    end
+  end
+
+  def link_redirects_back?(test_url)
+    redirect_to_url = Request.new(:head, test_url, follow: false).perform do |res|
+      res.headers['Location']
+    end
+
+    redirect_to_url == @link_back
+  end
+end