gitlab-org--gitlab-foss/lib/gitlab/middleware/read_only/controller.rb

156 lines
5.1 KiB
Ruby

# frozen_string_literal: true
module Gitlab
module Middleware
class ReadOnly
class Controller
DISALLOWED_METHODS = %w(POST PATCH PUT DELETE).freeze
APPLICATION_JSON = 'application/json'
APPLICATION_JSON_TYPES = %W{#{APPLICATION_JSON} application/vnd.git-lfs+json}.freeze
ERROR_MESSAGE = 'You cannot perform write operations on a read-only instance'
ALLOWLISTED_GIT_READ_ONLY_ROUTES = {
'repositories/git_http' => %w{git_upload_pack}
}.freeze
ALLOWLISTED_GIT_LFS_BATCH_ROUTES = {
'repositories/lfs_api' => %w{batch}
}.freeze
ALLOWLISTED_GIT_REVISION_ROUTES = {
'projects/compare' => %w{create}
}.freeze
ALLOWLISTED_SESSION_ROUTES = {
'sessions' => %w{destroy},
'admin/sessions' => %w{create destroy}
}.freeze
GRAPHQL_URL = '/api/graphql'
def initialize(app, env)
@app = app
@env = env
end
def call
if disallowed_request? && read_only?
Gitlab::AppLogger.debug('GitLab ReadOnly: preventing possible non read-only operation')
if json_request?
return [403, { 'Content-Type' => APPLICATION_JSON }, [{ 'message' => ERROR_MESSAGE }.to_json]]
else
rack_flash.alert = ERROR_MESSAGE
rack_session['flash'] = rack_flash.to_session_value
return [301, { 'Location' => last_visited_url }, []]
end
end
@app.call(@env)
end
private
def disallowed_request?
DISALLOWED_METHODS.include?(@env['REQUEST_METHOD']) &&
!allowlisted_routes
end
# Overridden in EE module
def read_only?
Gitlab::Database.read_only?
end
def json_request?
APPLICATION_JSON_TYPES.include?(request.media_type)
end
def rack_flash
@rack_flash ||= ActionDispatch::Flash::FlashHash.from_session_value(rack_session)
end
def rack_session
@env['rack.session']
end
def request
@env['actionpack.request'] ||= ActionDispatch::Request.new(@env)
end
def last_visited_url
@env['HTTP_REFERER'] || rack_session['user_return_to'] || Gitlab::Routing.url_helpers.root_url
end
def route_hash
@route_hash ||= Rails.application.routes.recognize_path(request_url, { method: request.request_method }) rescue {}
end
def request_url
request.url.chomp('/')
end
def request_path
@request_path ||= request.path.chomp('/')
end
def relative_url
File.join('', Gitlab.config.gitlab.relative_url_root).chomp('/')
end
# Overridden in EE module
def allowlisted_routes
workhorse_passthrough_route? || internal_route? || lfs_batch_route? || compare_git_revisions_route? || sidekiq_route? || session_route? || graphql_query?
end
# URL for requests passed through gitlab-workhorse to rails-web
# https://gitlab.com/gitlab-org/gitlab-workhorse/-/merge_requests/12
def workhorse_passthrough_route?
# Calling route_hash may be expensive. Only do it if we think there's a possible match
return false unless request.post? &&
request_path.end_with?('.git/git-upload-pack')
ALLOWLISTED_GIT_READ_ONLY_ROUTES[route_hash[:controller]]&.include?(route_hash[:action])
end
def internal_route?
ReadOnly.internal_routes.any? { |path| request.path.include?(path) }
end
def compare_git_revisions_route?
# Calling route_hash may be expensive. Only do it if we think there's a possible match
return false unless request.post? && request.path.end_with?('compare')
ALLOWLISTED_GIT_REVISION_ROUTES[route_hash[:controller]]&.include?(route_hash[:action])
end
# Batch upload requests are blocked in:
# https://gitlab.com/gitlab-org/gitlab/blob/master/app/controllers/repositories/lfs_api_controller.rb#L106
def lfs_batch_route?
# Calling route_hash may be expensive. Only do it if we think there's a possible match
return unless request_path.end_with?('/info/lfs/objects/batch')
ALLOWLISTED_GIT_LFS_BATCH_ROUTES[route_hash[:controller]]&.include?(route_hash[:action])
end
def session_route?
# Calling route_hash may be expensive. Only do it if we think there's a possible match
return false unless request.post? && request_path.end_with?('/users/sign_out',
'/admin/session', '/admin/session/destroy')
ALLOWLISTED_SESSION_ROUTES[route_hash[:controller]]&.include?(route_hash[:action])
end
def sidekiq_route?
request.path.start_with?("#{relative_url}/admin/sidekiq")
end
def graphql_query?
request.post? && request.path.start_with?(File.join(relative_url, GRAPHQL_URL))
end
end
end
end
end
Gitlab::Middleware::ReadOnly::Controller.prepend_mod_with('Gitlab::Middleware::ReadOnly::Controller')