JezK
Edit File: package.rb
# -*- coding: utf-8 -*- # frozen_string_literal: true #-- # Copyright (C) 2004 Mauricio Julio Fernández Pradier # See LICENSE.txt for additional licensing information. #++ # # Example using a Gem::Package # # Builds a .gem file given a Gem::Specification. A .gem file is a tarball # which contains a data.tar.gz and metadata.gz, and possibly signatures. # # require 'rubygems' # require 'rubygems/package' # # spec = Gem::Specification.new do |s| # s.summary = "Ruby based make-like utility." # s.name = 'rake' # s.version = PKG_VERSION # s.requirements << 'none' # s.files = PKG_FILES # s.description = <<-EOF # Rake is a Make-like program implemented in Ruby. Tasks # and dependencies are specified in standard Ruby syntax. # EOF # end # # Gem::Package.build spec # # Reads a .gem file. # # require 'rubygems' # require 'rubygems/package' # # the_gem = Gem::Package.new(path_to_dot_gem) # the_gem.contents # get the files in the gem # the_gem.extract_files destination_directory # extract the gem into a directory # the_gem.spec # get the spec out of the gem # the_gem.verify # check the gem is OK (contains valid gem specification, contains a not corrupt contents archive) # # #files are the files in the .gem tar file, not the Ruby files in the gem # #extract_files and #contents automatically call #verify require 'rubygems/security' require 'rubygems/specification' require 'rubygems/user_interaction' require 'zlib' class Gem::Package include Gem::UserInteraction class Error < Gem::Exception; end class FormatError < Error attr_reader :path def initialize message, source = nil if source @path = source.path message = message + " in #{path}" if path end super message end end class PathError < Error def initialize destination, destination_dir super "installing into parent path %s of %s is not allowed" % [destination, destination_dir] end end class NonSeekableIO < Error; end class TooLongFileName < Error; end ## # Raised when a tar file is corrupt class TarInvalidError < Error; end attr_accessor :build_time # :nodoc: ## # Checksums for the contents of the package attr_reader :checksums ## # The files in this package. This is not the contents of the gem, just the # files in the top-level container. attr_reader :files ## # The security policy used for verifying the contents of this package. attr_accessor :security_policy ## # Sets the Gem::Specification to use to build this package. attr_writer :spec def self.build spec, skip_validation=false gem_file = spec.file_name package = new gem_file package.spec = spec package.build skip_validation gem_file end ## # Creates a new Gem::Package for the file at +gem+. +gem+ can also be # provided as an IO object. # # If +gem+ is an existing file in the old format a Gem::Package::Old will be # returned. def self.new gem, security_policy = nil gem = if gem.is_a?(Gem::Package::Source) gem elsif gem.respond_to? :read Gem::Package::IOSource.new gem else Gem::Package::FileSource.new gem end return super unless Gem::Package == self return super unless gem.present? return super unless gem.start return super unless gem.start.include? 'MD5SUM =' Gem::Package::Old.new gem end ## # Creates a new package that will read or write to the file +gem+. def initialize gem, security_policy # :notnew: @gem = gem @build_time = Time.now @checksums = {} @contents = nil @digests = Hash.new { |h, algorithm| h[algorithm] = {} } @files = nil @security_policy = security_policy @signatures = {} @signer = nil @spec = nil end ## # Copies this package to +path+ (if possible) def copy_to path FileUtils.cp @gem.path, path unless File.exist? path end ## # Adds a checksum for each entry in the gem to checksums.yaml.gz. def add_checksums tar Gem.load_yaml checksums_by_algorithm = Hash.new { |h, algorithm| h[algorithm] = {} } @checksums.each do |name, digests| digests.each do |algorithm, digest| checksums_by_algorithm[algorithm][name] = digest.hexdigest end end tar.add_file_signed 'checksums.yaml.gz', 0444, @signer do |io| gzip_to io do |gz_io| YAML.dump checksums_by_algorithm, gz_io end end end ## # Adds the files listed in the packages's Gem::Specification to data.tar.gz # and adds this file to the +tar+. def add_contents tar # :nodoc: digests = tar.add_file_signed 'data.tar.gz', 0444, @signer do |io| gzip_to io do |gz_io| Gem::Package::TarWriter.new gz_io do |data_tar| add_files data_tar end end end @checksums['data.tar.gz'] = digests end ## # Adds files included the package's Gem::Specification to the +tar+ file def add_files tar # :nodoc: @spec.files.each do |file| stat = File.lstat file if stat.symlink? relative_dir = File.dirname(file).sub("#{Dir.pwd}/", '') target_path = File.join(relative_dir, File.readlink(file)) tar.add_symlink file, target_path, stat.mode end next unless stat.file? tar.add_file_simple file, stat.mode, stat.size do |dst_io| File.open file, 'rb' do |src_io| dst_io.write src_io.read 16384 until src_io.eof? end end end end ## # Adds the package's Gem::Specification to the +tar+ file def add_metadata tar # :nodoc: digests = tar.add_file_signed 'metadata.gz', 0444, @signer do |io| gzip_to io do |gz_io| gz_io.write @spec.to_yaml end end @checksums['metadata.gz'] = digests end ## # Builds this package based on the specification set by #spec= def build skip_validation = false Gem.load_yaml require 'rubygems/security' @spec.mark_version @spec.validate unless skip_validation setup_signer @gem.with_write_io do |gem_io| Gem::Package::TarWriter.new gem_io do |gem| add_metadata gem add_contents gem add_checksums gem end end say <<-EOM Successfully built RubyGem Name: #{@spec.name} Version: #{@spec.version} File: #{File.basename @spec.cache_file} EOM ensure @signer = nil end ## # A list of file names contained in this gem def contents return @contents if @contents verify unless @spec @contents = [] @gem.with_read_io do |io| gem_tar = Gem::Package::TarReader.new io gem_tar.each do |entry| next unless entry.full_name == 'data.tar.gz' open_tar_gz entry do |pkg_tar| pkg_tar.each do |contents_entry| @contents << contents_entry.full_name end end return @contents end end end ## # Creates a digest of the TarEntry +entry+ from the digest algorithm set by # the security policy. def digest entry # :nodoc: algorithms = if @checksums then @checksums.keys else [Gem::Security::DIGEST_NAME].compact end algorithms.each do |algorithm| digester = if defined?(OpenSSL::Digest) then OpenSSL::Digest.new algorithm else Digest.const_get(algorithm).new end digester << entry.read(16384) until entry.eof? entry.rewind @digests[algorithm][entry.full_name] = digester end @digests end ## # Extracts the files in this package into +destination_dir+ # # If +pattern+ is specified, only entries matching that glob will be # extracted. def extract_files destination_dir, pattern = "*" verify unless @spec FileUtils.mkdir_p destination_dir @gem.with_read_io do |io| reader = Gem::Package::TarReader.new io reader.each do |entry| next unless entry.full_name == 'data.tar.gz' extract_tar_gz entry, destination_dir, pattern return # ignore further entries end end end ## # Extracts all the files in the gzipped tar archive +io+ into # +destination_dir+. # # If an entry in the archive contains a relative path above # +destination_dir+ or an absolute path is encountered an exception is # raised. # # If +pattern+ is specified, only entries matching that glob will be # extracted. def extract_tar_gz io, destination_dir, pattern = "*" # :nodoc: open_tar_gz io do |tar| tar.each do |entry| next unless File.fnmatch pattern, entry.full_name, File::FNM_DOTMATCH destination = install_location entry.full_name, destination_dir FileUtils.rm_rf destination mkdir_options = {} mkdir_options[:mode] = entry.header.mode if entry.directory? mkdir = if entry.directory? then destination else File.dirname destination end mkdir_p_safe mkdir, mkdir_options, destination_dir, entry.full_name File.open destination, 'wb' do |out| out.write entry.read FileUtils.chmod entry.header.mode, destination end if entry.file? File.symlink(entry.header.linkname, destination) if entry.symlink? verbose destination end end end ## # Gzips content written to +gz_io+ to +io+. #-- # Also sets the gzip modification time to the package build time to ease # testing. def gzip_to io # :yields: gz_io gz_io = Zlib::GzipWriter.new io, Zlib::BEST_COMPRESSION gz_io.mtime = @build_time yield gz_io ensure gz_io.close end ## # Returns the full path for installing +filename+. # # If +filename+ is not inside +destination_dir+ an exception is raised. def install_location filename, destination_dir # :nodoc: raise Gem::Package::PathError.new(filename, destination_dir) if filename.start_with? '/' destination_dir = realpath destination_dir destination_dir = File.expand_path destination_dir destination = File.join destination_dir, filename destination = File.expand_path destination raise Gem::Package::PathError.new(destination, destination_dir) unless destination.start_with? destination_dir + '/' begin real_destination = File.expand_path(File.realpath(destination)) rescue # it's fine if the destination doesn't exist, because rm -rf'ing it can't cause any damage nil else raise Gem::Package::PathError.new(real_destination, destination_dir) unless real_destination.start_with? destination_dir + '/' end destination.untaint destination end def mkdir_p_safe mkdir, mkdir_options, destination_dir, file_name destination_dir = realpath File.expand_path(destination_dir) parts = mkdir.split(File::SEPARATOR) parts.reduce do |path, basename| path = realpath path unless path == "" path = File.expand_path(path + File::SEPARATOR + basename) lstat = File.lstat path rescue nil if !lstat || !lstat.directory? unless path.start_with? destination_dir and (FileUtils.mkdir path, mkdir_options rescue false) raise Gem::Package::PathError.new(file_name, destination_dir) end end path end end ## # Loads a Gem::Specification from the TarEntry +entry+ def load_spec entry # :nodoc: case entry.full_name when 'metadata' then @spec = Gem::Specification.from_yaml entry.read when 'metadata.gz' then args = [entry] args << { :external_encoding => Encoding::UTF_8 } if Object.const_defined?(:Encoding) && Zlib::GzipReader.method(:wrap).arity != 1 Zlib::GzipReader.wrap(*args) do |gzio| @spec = Gem::Specification.from_yaml gzio.read end end end ## # Opens +io+ as a gzipped tar archive def open_tar_gz io # :nodoc: Zlib::GzipReader.wrap io do |gzio| tar = Gem::Package::TarReader.new gzio yield tar end end ## # Reads and loads checksums.yaml.gz from the tar file +gem+ def read_checksums gem Gem.load_yaml @checksums = gem.seek 'checksums.yaml.gz' do |entry| Zlib::GzipReader.wrap entry do |gz_io| Gem::SafeYAML.safe_load gz_io.read end end end ## # Prepares the gem for signing and checksum generation. If a signing # certificate and key are not present only checksum generation is set up. def setup_signer passphrase = ENV['GEM_PRIVATE_KEY_PASSPHRASE'] if @spec.signing_key then @signer = Gem::Security::Signer.new @spec.signing_key, @spec.cert_chain, passphrase @spec.signing_key = nil @spec.cert_chain = @signer.cert_chain.map { |cert| cert.to_s } else @signer = Gem::Security::Signer.new nil, nil, passphrase @spec.cert_chain = @signer.cert_chain.map { |cert| cert.to_pem } if @signer.cert_chain end end ## # The spec for this gem. # # If this is a package for a built gem the spec is loaded from the # gem and returned. If this is a package for a gem being built the provided # spec is returned. def spec verify unless @spec @spec end ## # Verifies that this gem: # # * Contains a valid gem specification # * Contains a contents archive # * The contents archive is not corrupt # # After verification the gem specification from the gem is available from # #spec def verify @files = [] @spec = nil @gem.with_read_io do |io| Gem::Package::TarReader.new io do |reader| read_checksums reader verify_files reader end end verify_checksums @digests, @checksums @security_policy.verify_signatures @spec, @digests, @signatures if @security_policy true rescue Gem::Security::Exception @spec = nil @files = [] raise rescue Errno::ENOENT => e raise Gem::Package::FormatError.new e.message rescue Gem::Package::TarInvalidError => e raise Gem::Package::FormatError.new e.message, @gem end ## # Verifies the +checksums+ against the +digests+. This check is not # cryptographically secure. Missing checksums are ignored. def verify_checksums digests, checksums # :nodoc: return unless checksums checksums.sort.each do |algorithm, gem_digests| gem_digests.sort.each do |file_name, gem_hexdigest| computed_digest = digests[algorithm][file_name] unless computed_digest.hexdigest == gem_hexdigest then raise Gem::Package::FormatError.new \ "#{algorithm} checksum mismatch for #{file_name}", @gem end end end end ## # Verifies +entry+ in a .gem file. def verify_entry entry file_name = entry.full_name @files << file_name case file_name when /\.sig$/ then @signatures[$`] = entry.read if @security_policy return else digest entry end case file_name when /^metadata(.gz)?$/ then load_spec entry when 'data.tar.gz' then verify_gz entry end rescue => e message = "package is corrupt, exception while verifying: " + "#{e.message} (#{e.class})" raise Gem::Package::FormatError.new message, @gem end ## # Verifies the files of the +gem+ def verify_files gem gem.each do |entry| verify_entry entry end unless @spec then raise Gem::Package::FormatError.new 'package metadata is missing', @gem end unless @files.include? 'data.tar.gz' then raise Gem::Package::FormatError.new \ 'package content (data.tar.gz) is missing', @gem end if duplicates = @files.group_by {|f| f }.select {|k,v| v.size > 1 }.map(&:first) and duplicates.any? raise Gem::Security::Exception, "duplicate files in the package: (#{duplicates.map(&:inspect).join(', ')})" end end ## # Verifies that +entry+ is a valid gzipped file. def verify_gz entry # :nodoc: Zlib::GzipReader.wrap entry do |gzio| gzio.read 16384 until gzio.eof? # gzip checksum verification end rescue Zlib::GzipFile::Error => e raise Gem::Package::FormatError.new(e.message, entry.full_name) end if File.respond_to? :realpath def realpath file File.realpath file end else def realpath file file end end end require 'rubygems/package/digest_io' require 'rubygems/package/source' require 'rubygems/package/file_source' require 'rubygems/package/io_source' require 'rubygems/package/old' require 'rubygems/package/tar_header' require 'rubygems/package/tar_reader' require 'rubygems/package/tar_reader/entry' require 'rubygems/package/tar_writer'