gitlab-ce/lib/gitlab/middleware/path_traversal_check.rb

94 lines
2.6 KiB
Ruby

# frozen_string_literal: true
module Gitlab
module Middleware
class PathTraversalCheck
PATH_TRAVERSAL_MESSAGE = 'Potential path traversal attempt detected'
EXCLUDED_EXACT_PATHS = %w[/search].freeze
EXCLUDED_PATH_PREFIXES = %w[/search/].freeze
EXCLUDED_API_PATHS = %w[/search].freeze
EXCLUDED_PROJECT_API_PATHS = %w[/search].freeze
EXCLUDED_GROUP_API_PATHS = %w[/search].freeze
API_PREFIX = %r{/api/[^/]+}
API_SUFFIX = %r{(?:\.[^/]+)?}
EXCLUDED_API_PATHS_REGEX = [
EXCLUDED_API_PATHS.map do |path|
%r{\A#{API_PREFIX}#{path}#{API_SUFFIX}\z}
end.freeze,
EXCLUDED_PROJECT_API_PATHS.map do |path|
%r{\A#{API_PREFIX}/projects/[^/]+(?:/-)?#{path}#{API_SUFFIX}\z}
end.freeze,
EXCLUDED_GROUP_API_PATHS.map do |path|
%r{\A#{API_PREFIX}/groups/[^/]+(?:/-)?#{path}#{API_SUFFIX}\z}
end.freeze
].flatten.freeze
def initialize(app)
@app = app
end
def call(env)
return @app.call(env) unless Feature.enabled?(:check_path_traversal_middleware, Feature.current_request)
log_params = {}
execution_time = measure_execution_time do
request = ::Rack::Request.new(env.dup)
check(request, log_params) unless excluded?(request)
end
log_params[:duration_ms] = execution_time.round(5) if execution_time
result = @app.call(env)
unless log_params.empty?
log_params[:status] = result.first
log(log_params)
end
result
end
private
def measure_execution_time(&blk)
if Feature.enabled?(:log_execution_time_path_traversal_middleware, Feature.current_request)
Benchmark.ms(&blk)
else
yield
nil
end
end
def check(request, log_params)
decoded_fullpath = CGI.unescape(request.fullpath)
::Gitlab::PathTraversal.check_path_traversal!(decoded_fullpath, skip_decoding: true)
rescue ::Gitlab::PathTraversal::PathTraversalAttackError
log_params[:method] = request.request_method
log_params[:fullpath] = request.fullpath
log_params[:message] = PATH_TRAVERSAL_MESSAGE
end
def excluded?(request)
path = request.path
return true if path.in?(EXCLUDED_EXACT_PATHS)
return true if EXCLUDED_PATH_PREFIXES.any? { |p| path.start_with?(p) }
return true if EXCLUDED_API_PATHS_REGEX.any? { |r| path.match?(r) }
false
end
def log(payload)
Gitlab::AppLogger.warn(
payload.merge(class_name: self.class.name)
)
end
end
end
end