Class: Gem::Package

Inherits:
Object
  • Object
show all
Includes:
UserInteraction
Defined in:
lib/rubygems/package.rb

Direct Known Subclasses

Old

Defined Under Namespace

Classes: DigestIO, Error, FileSource, FormatError, IOSource, NonSeekableIO, Old, PathError, Source, TarHeader, TarInvalidError, TarReader, TarTestCase, TarWriter, TooLongFileName

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Methods included from UserInteraction

#alert, #alert_error, #alert_warning, #ask, #ask_for_password, #ask_yes_no, #choose_from_list, #say, #terminate_interaction, #verbose

Methods included from DefaultUserInteraction

ui, #ui, #ui=, ui=, use_ui, #use_ui

Constructor Details

#initialize(gem, security_policy) ⇒ Package

Creates a new package that will read or write to the file gem.


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# File 'lib/rubygems/package.rb', line 160

def initialize gem, security_policy # :notnew:
  @gem = gem

  @build_time      = ENV["SOURCE_DATE_EPOCH"] ? Time.at(ENV["SOURCE_DATE_EPOCH"].to_i).utc : Time.now
  @checksums       = {}
  @contents        = nil
  @digests         = Hash.new { |h, algorithm| h[algorithm] = {} }
  @files           = nil
  @security_policy = security_policy
  @signatures      = {}
  @signer          = nil
  @spec            = nil
end

Instance Attribute Details

#build_timeObject

:nodoc:


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# File 'lib/rubygems/package.rb', line 87

def build_time
  @build_time
end

#checksumsObject (readonly)

Checksums for the contents of the package


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# File 'lib/rubygems/package.rb', line 92

def checksums
  @checksums
end

#data_modeObject

Permission for other files


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# File 'lib/rubygems/package.rb', line 120

def data_mode
  @data_mode
end

#dir_modeObject

Permission for directories


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# File 'lib/rubygems/package.rb', line 112

def dir_mode
  @dir_mode
end

#filesObject (readonly)

The files in this package. This is not the contents of the gem, just the files in the top-level container.


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# File 'lib/rubygems/package.rb', line 98

def files
  @files
end

#prog_modeObject

Permission for program files


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# File 'lib/rubygems/package.rb', line 116

def prog_mode
  @prog_mode
end

#security_policyObject

The security policy used for verifying the contents of this package.


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# File 'lib/rubygems/package.rb', line 103

def security_policy
  @security_policy
end

#specObject

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.


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# File 'lib/rubygems/package.rb', line 555

def spec
  verify unless @spec

  @spec
end

Class Method Details

.build(spec, skip_validation = false, strict_validation = false) ⇒ Object


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# File 'lib/rubygems/package.rb', line 122

def self.build spec, skip_validation = false, strict_validation = false
  gem_file = spec.file_name

  package = new gem_file
  package.spec = spec
  package.build skip_validation, strict_validation

  gem_file
end

.new(gem, security_policy = nil) ⇒ Object

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.


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# File 'lib/rubygems/package.rb', line 139

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

Instance Method Details

#add_checksums(tar) ⇒ Object

Adds a checksum for each entry in the gem to checksums.yaml.gz.


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# File 'lib/rubygems/package.rb', line 184

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

#add_contents(tar) ⇒ Object

Adds the files listed in the packages's Gem::Specification to data.tar.gz and adds this file to the tar.


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# File 'lib/rubygems/package.rb', line 206

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

#add_files(tar) ⇒ Object

Adds files included the package's Gem::Specification to the tar file


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# File 'lib/rubygems/package.rb', line 221

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

#add_metadata(tar) ⇒ Object

Adds the package's Gem::Specification to the tar file


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# File 'lib/rubygems/package.rb', line 244

def  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

#build(skip_validation = false, strict_validation = false) ⇒ Object

Builds this package based on the specification set by #spec=


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# File 'lib/rubygems/package.rb', line 257

def build skip_validation = false, strict_validation = false
  raise ArgumentError, "skip_validation = true and strict_validation = true are incompatible" if skip_validation && strict_validation

  Gem.load_yaml
  require 'rubygems/security'

  @spec.mark_version
  @spec.validate true, strict_validation unless skip_validation

  setup_signer(
    signer_options: {
      expiration_length_days: Gem.configuration.cert_expiration_length_days
    }
  )

  @gem.with_write_io do |gem_io|
    Gem::Package::TarWriter.new gem_io do |gem|
       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

#contentsObject

A list of file names contained in this gem


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# File 'lib/rubygems/package.rb', line 293

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

#copy_to(path) ⇒ Object

Copies this package to path (if possible)


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# File 'lib/rubygems/package.rb', line 177

def copy_to path
  FileUtils.cp @gem.path, path unless File.exist? path
end

#digest(entry) ⇒ Object

Creates a digest of the TarEntry entry from the digest algorithm set by the security policy.


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# File 'lib/rubygems/package.rb', line 321

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

#extract_files(destination_dir, pattern = "*") ⇒ Object

Extracts the files in this package into destination_dir

If pattern is specified, only entries matching that glob will be extracted.


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# File 'lib/rubygems/package.rb', line 352

def extract_files destination_dir, pattern = "*"
  verify unless @spec

  FileUtils.mkdir_p destination_dir, :mode => dir_mode && 0700

  @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

#extract_tar_gz(io, destination_dir, pattern = "*") ⇒ Object

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.


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# File 'lib/rubygems/package.rb', line 381

def extract_tar_gz io, destination_dir, pattern = "*" # :nodoc:
  directories = [] if dir_mode
  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] = dir_mode ? 0700 : (entry.header.mode if entry.directory?)
      mkdir =
        if entry.directory? then
          destination
        else
          File.dirname destination
        end
      directories << mkdir if directories

      mkdir_p_safe mkdir, mkdir_options, destination_dir, entry.full_name

      File.open destination, 'wb' do |out|
        out.write entry.read
        FileUtils.chmod file_mode(entry.header.mode), destination
      end if entry.file?

      File.symlink(entry.header.linkname, destination) if entry.symlink?

      verbose destination
    end
  end

  if directories
    directories.uniq!
    File.chmod(dir_mode, *directories)
  end
end

#file_mode(mode) ⇒ Object

:nodoc:


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# File 'lib/rubygems/package.rb', line 420

def file_mode(mode) # :nodoc:
  ((mode & 0111).zero? ? data_mode : prog_mode) || mode
end

#gzip_to(io) ⇒ Object

Gzips content written to gz_io to io. – Also sets the gzip modification time to the package build time to ease testing.


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# File 'lib/rubygems/package.rb', line 430

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

#install_location(filename, destination_dir) ⇒ Object

Returns the full path for installing filename.

If filename is not inside destination_dir an exception is raised.


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# File 'lib/rubygems/package.rb', line 444

def install_location filename, destination_dir # :nodoc:
  raise Gem::Package::PathError.new(filename, destination_dir) if
    filename.start_with? '/'

  destination_dir = File.expand_path(File.realpath(destination_dir))
  destination = File.expand_path(File.join(destination_dir, filename))

  raise Gem::Package::PathError.new(destination, destination_dir) unless
    destination.start_with? destination_dir + '/'

  destination.untaint
  destination
end

#load_spec(entry) ⇒ Object

Loads a Gem::Specification from the TarEntry entry


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# File 'lib/rubygems/package.rb', line 485

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
      Zlib::GzipReader.method(:wrap).arity != 1

    Zlib::GzipReader.wrap(*args) do |gzio|
      @spec = Gem::Specification.from_yaml gzio.read
    end
  end
end

#mkdir_p_safe(mkdir, mkdir_options, destination_dir, file_name) ⇒ Object


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# File 'lib/rubygems/package.rb', line 466

def mkdir_p_safe mkdir, mkdir_options, destination_dir, file_name
  destination_dir = File.realpath(File.expand_path(destination_dir))
  parts = mkdir.split(File::SEPARATOR)
  parts.reduce do |path, basename|
    path = File.realpath(path) unless path == ""
    path = File.expand_path(path + File::SEPARATOR + basename)
    lstat = File.lstat path rescue nil
    if !lstat || !lstat.directory?
      unless normalize_path(path).start_with? normalize_path(destination_dir) and (FileUtils.mkdir path, mkdir_options rescue false)
        raise Gem::Package::PathError.new(file_name, destination_dir)
      end
    end
    path
  end
end

#normalize_path(pathname) ⇒ Object


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# File 'lib/rubygems/package.rb', line 458

def normalize_path(pathname)
  if Gem.win_platform?
    pathname.downcase
  else
    pathname
  end
end

#open_tar_gz(io) ⇒ Object

Opens io as a gzipped tar archive


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# File 'lib/rubygems/package.rb', line 503

def open_tar_gz io # :nodoc:
  Zlib::GzipReader.wrap io do |gzio|
    tar = Gem::Package::TarReader.new gzio

    yield tar
  end
end

#read_checksums(gem) ⇒ Object

Reads and loads checksums.yaml.gz from the tar file gem


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# File 'lib/rubygems/package.rb', line 514

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

#setup_signer(signer_options: {}) ⇒ Object

Prepares the gem for signing and checksum generation. If a signing certificate and key are not present only checksum generation is set up.


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# File 'lib/rubygems/package.rb', line 528

def setup_signer(signer_options: {})
  passphrase = ENV['GEM_PRIVATE_KEY_PASSPHRASE']
  if @spec.signing_key then
    @signer =
      Gem::Security::Signer.new(
        @spec.signing_key,
        @spec.cert_chain,
        passphrase,
        signer_options
      )

    @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

#verifyObject

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


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# File 'lib/rubygems/package.rb', line 571

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

#verify_checksums(digests, checksums) ⇒ Object

Verifies the checksums against the digests. This check is not cryptographically secure. Missing checksums are ignored.


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# File 'lib/rubygems/package.rb', line 603

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

#verify_entry(entry) ⇒ Object

Verifies entry in a .gem file.


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# File 'lib/rubygems/package.rb', line 621

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", "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

#verify_files(gem) ⇒ Object

Verifies the files of the gem


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# File 'lib/rubygems/package.rb', line 648

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

#verify_gz(entry) ⇒ Object

Verifies that entry is a valid gzipped file.


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# File 'lib/rubygems/package.rb', line 670

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