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, FormatError, NonSeekableIO, Old, PathError, 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

Methods included from DefaultUserInteraction

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

Constructor Details

#initialize(gem) ⇒ Package

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



137
138
139
140
141
142
143
144
145
146
147
148
149
# File 'lib/rubygems/package.rb', line 137

def initialize gem # :notnew:
  @gem = gem

  @build_time      = Time.now
  @checksums       = {}
  @contents        = nil
  @digests         = Hash.new { |h, algorithm| h[algorithm] = {} }
  @files           = nil
  @security_policy = nil
  @signatures      = {}
  @signer          = nil
  @spec            = nil
end

Instance Attribute Details

#build_timeObject

:nodoc:



83
84
85
# File 'lib/rubygems/package.rb', line 83

def build_time
  @build_time
end

#checksumsObject (readonly)

Checksums for the contents of the package



88
89
90
# File 'lib/rubygems/package.rb', line 88

def checksums
  @checksums
end

#filesObject (readonly)

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



94
95
96
# File 'lib/rubygems/package.rb', line 94

def files
  @files
end

#security_policyObject

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



99
100
101
# File 'lib/rubygems/package.rb', line 99

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.



446
447
448
449
450
# File 'lib/rubygems/package.rb', line 446

def spec
  verify unless @spec

  @spec
end

Class Method Details

.build(spec, skip_validation = false) ⇒ Object



106
107
108
109
110
111
112
113
114
# File 'lib/rubygems/package.rb', line 106

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

.new(gem) ⇒ Object

Creates a new Gem::Package for the file at gem.

If gem is an existing file in the old format a Gem::Package::Old will be returned.



122
123
124
125
126
127
128
129
130
131
132
# File 'lib/rubygems/package.rb', line 122

def self.new gem
  return super unless Gem::Package == self
  return super unless File.exist? gem

  start = File.read gem, 20

  return super unless start
  return super unless 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.



154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
# File 'lib/rubygems/package.rb', line 154

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.



176
177
178
179
180
181
182
183
184
185
186
# File 'lib/rubygems/package.rb', line 176

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



191
192
193
194
195
196
197
198
199
200
201
202
203
# File 'lib/rubygems/package.rb', line 191

def add_files tar # :nodoc:
  @spec.files.each do |file|
    stat = File.stat file

    next unless stat.file?

    tar.add_file_simple file, stat.mode, stat.size do |dst_io|
      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



208
209
210
211
212
213
214
215
216
# File 'lib/rubygems/package.rb', line 208

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) ⇒ Object

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



221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
# File 'lib/rubygems/package.rb', line 221

def build skip_validation = false
  Gem.load_yaml
  require 'rubygems/security'

  @spec.mark_version
  @spec.validate unless skip_validation

  setup_signer

  open @gem, 'wb' 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



251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
# File 'lib/rubygems/package.rb', line 251

def contents
  return @contents if @contents

  verify unless @spec

  @contents = []

  open @gem, 'rb' 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

#digest(entry) ⇒ Object

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



279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
# File 'lib/rubygems/package.rb', line 279

def digest entry # :nodoc:
  algorithms = if @checksums then
                 @checksums.keys
               else
                 [Gem::Security::DIGEST_NAME]
               end

  algorithms.each do |algorithm|
    digester = OpenSSL::Digest.new algorithm

    digester << entry.read(16384) until entry.eof?

    entry.rewind

    @digests[algorithm][entry.full_name] = digester
  end

  @digests
end

#extract_files(destination_dir) ⇒ Object

Extracts the files in this package into destination_dir



302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
# File 'lib/rubygems/package.rb', line 302

def extract_files destination_dir
  verify unless @spec

  FileUtils.mkdir_p destination_dir

  open @gem, 'rb' 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

      return # ignore further entries
    end
  end
end

#extract_tar_gz(io, destination_dir) ⇒ 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.



328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
# File 'lib/rubygems/package.rb', line 328

def extract_tar_gz io, destination_dir # :nodoc:
  open_tar_gz io do |tar|
    tar.each do |entry|
      destination = install_location entry.full_name, destination_dir

      FileUtils.rm_rf destination

      FileUtils.mkdir_p File.dirname destination

      open destination, 'wb', entry.header.mode do |out|
        out.write entry.read
        out.fsync rescue nil # for filesystems without fsync(2)
      end

      say destination if Gem.configuration.really_verbose
    end
  end
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.



353
354
355
356
357
358
359
360
# File 'lib/rubygems/package.rb', line 353

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.



367
368
369
370
371
372
373
374
375
376
377
378
379
# File 'lib/rubygems/package.rb', line 367

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

  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

  destination.untaint
  destination
end

#load_spec(entry) ⇒ Object

Loads a Gem::Specification from the TarEntry entry



384
385
386
387
388
389
390
391
392
393
394
395
396
397
# File 'lib/rubygems/package.rb', line 384

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

#open_tar_gz(io) ⇒ Object

Opens io as a gzipped tar archive



402
403
404
405
406
407
408
# File 'lib/rubygems/package.rb', line 402

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



413
414
415
416
417
418
419
420
421
# File 'lib/rubygems/package.rb', line 413

def read_checksums gem
  Gem.load_yaml

  @checksums = gem.seek 'checksums.yaml.gz' do |entry|
    Zlib::GzipReader.wrap entry do |gz_io|
      YAML.load gz_io.read
    end
  end
end

#setup_signerObject

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



427
428
429
430
431
432
433
434
435
436
437
# File 'lib/rubygems/package.rb', line 427

def setup_signer
  if @spec.signing_key then
    @signer = Gem::Security::Signer.new @spec.signing_key, @spec.cert_chain
    @spec.signing_key = nil
    @spec.cert_chain = @signer.cert_chain.map { |cert| cert.to_s }
  else
    @signer = Gem::Security::Signer.new nil, nil
    @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



462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
# File 'lib/rubygems/package.rb', line 462

def verify
  @files     = []
  @spec      = nil

  open @gem, 'rb' 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.



494
495
496
497
498
499
500
501
502
503
504
505
506
507
# File 'lib/rubygems/package.rb', line 494

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_files(gem) ⇒ Object

Verifies the files of the gem



512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
# File 'lib/rubygems/package.rb', line 512

def verify_files gem
  gem.each do |entry|
    file_name = entry.full_name
    @files << file_name

    case file_name
    when /\.sig$/ then
      @signatures[$`] = entry.read if @security_policy
      next
    else
      digest entry
    end

    case file_name
    when /^metadata(.gz)?$/ then
      load_spec entry
    when 'data.tar.gz' then
      verify_gz entry
    end
  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
end

#verify_gz(entry) ⇒ Object

Verifies that entry is a valid gzipped file.



546
547
548
549
550
551
552
# File 'lib/rubygems/package.rb', line 546

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