1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
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
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
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
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
|
# frozen_string_literal: true
# Check a user's access to perform a git action. All public methods in this
# class return an instance of `GitlabAccessStatus`
module Gitlab
class GitAccess
include Gitlab::Utils::StrongMemoize
ForbiddenError = Class.new(StandardError)
NotFoundError = Class.new(StandardError)
TimeoutError = Class.new(StandardError)
# Use the magic string '_any' to indicate we do not know what the
# changes are. This is also what gitlab-shell does.
ANY = '_any'
ERROR_MESSAGES = {
upload: 'You are not allowed to upload code for this project.',
download: 'You are not allowed to download code from this project.',
auth_upload: 'You are not allowed to upload code.',
auth_download: 'You are not allowed to download code.',
deploy_key_upload: 'This deploy key does not have write access to this project.',
no_repo: 'A repository for this project does not exist yet.',
project_not_found: "The project you were looking for could not be found or you don't have permission to view it.",
command_not_allowed: "The command you're trying to execute is not allowed.",
upload_pack_disabled_over_http: 'Pulling over HTTP is not allowed.',
receive_pack_disabled_over_http: 'Pushing over HTTP is not allowed.',
read_only: 'The repository is temporarily read-only. Please try again later.',
cannot_push_to_read_only: "You can't push code to a read-only GitLab instance.",
push_code: 'You are not allowed to push code to this project.'
}.freeze
INTERNAL_TIMEOUT = 50.seconds.freeze
LOG_HEADER = <<~MESSAGE
Push operation timed out
Timing information for debugging purposes:
MESSAGE
DOWNLOAD_COMMANDS = %w{git-upload-pack git-upload-archive}.freeze
PUSH_COMMANDS = %w{git-receive-pack}.freeze
ALL_COMMANDS = DOWNLOAD_COMMANDS + PUSH_COMMANDS
attr_reader :actor, :protocol, :authentication_abilities,
:repository_path, :redirected_path, :auth_result_type,
:cmd, :changes
attr_accessor :container
def self.error_message(key)
self.ancestors.each do |cls|
return cls.const_get('ERROR_MESSAGES', false).fetch(key)
rescue NameError, KeyError
next
end
raise ArgumentError, "No error message defined for #{key}"
end
def initialize(actor, container, protocol, authentication_abilities:, repository_path: nil, redirected_path: nil, auth_result_type: nil)
@actor = actor
@container = container
@protocol = protocol
@authentication_abilities = Array(authentication_abilities)
@repository_path = repository_path
@redirected_path = redirected_path
@auth_result_type = auth_result_type
end
def check(cmd, changes)
@changes = changes
@cmd = cmd
check_protocol!
check_valid_actor!
check_active_user!
check_authentication_abilities!
check_command_disabled!
check_command_existence!
custom_action = check_custom_action
return custom_action if custom_action
check_db_accessibility!
check_container!
check_repository_existence!
case cmd
when *DOWNLOAD_COMMANDS
check_download_access!
when *PUSH_COMMANDS
check_push_access!
end
check_additional_conditions!
success_result
end
def logger
@logger ||= Checks::TimedLogger.new(timeout: INTERNAL_TIMEOUT, header: LOG_HEADER)
end
def guest_can_download_code?
Guest.can?(download_ability, container)
end
def deploy_key_can_download_code?
authentication_abilities.include?(:download_code) &&
deploy_key? &&
deploy_key.has_access_to?(container) &&
(project? && project&.repository_access_level != ::Featurable::DISABLED)
end
def user_can_download_code?
authentication_abilities.include?(:download_code) &&
user_access.can_do_action?(download_ability)
end
# @return [Symbol] the name of a Declarative Policy ability to check
def download_ability
raise NotImplementedError
end
# @return [Symbol] the name of a Declarative Policy ability to check
def push_ability
raise NotImplementedError
end
def build_can_download_code?
authentication_abilities.include?(:build_download_code) && user_access.can_do_action?(:build_download_code)
end
def request_from_ci_build?
return false unless protocol == 'http'
auth_result_type == :build || auth_result_type == :ci
end
def protocol_allowed?
Gitlab::ProtocolAccess.allowed?(protocol)
end
private
def check_container!
# Strict nil check, to avoid any surprises with Object#present?
# which can delegate to #empty?
raise NotFoundError, not_found_message if container.nil?
check_project! if project?
add_container_moved_message!
end
def check_project!
check_project_accessibility!
end
def check_custom_action
# no-op: Overridden in EE
end
def check_for_console_messages
return console_messages unless key?
key_status = Gitlab::Auth::KeyStatusChecker.new(actor)
if key_status.show_console_message?
console_messages.push(key_status.console_message)
else
console_messages
end
end
def console_messages
[]
end
def check_valid_actor!
return unless key?
unless actor.valid?
raise ForbiddenError, "Your SSH key #{actor.errors[:key].first}."
end
end
def check_protocol!
return if request_from_ci_build?
unless protocol_allowed?
raise ForbiddenError, "Git access over #{protocol.upcase} is not allowed"
end
end
def check_active_user!
return unless user
unless user_access.allowed?
message = Gitlab::Auth::UserAccessDeniedReason.new(user).rejection_message
raise ForbiddenError, message
end
end
def check_authentication_abilities!
case cmd
when *DOWNLOAD_COMMANDS
unless authentication_abilities.include?(:download_code) || authentication_abilities.include?(:build_download_code)
raise ForbiddenError, error_message(:auth_download)
end
when *PUSH_COMMANDS
unless authentication_abilities.include?(:push_code)
raise ForbiddenError, error_message(:auth_upload)
end
end
end
def check_project_accessibility!
raise NotFoundError, not_found_message unless can_read_project?
end
def not_found_message
error_message(:project_not_found)
end
def add_container_moved_message!
return if redirected_path.nil?
container_moved = Checks::ContainerMoved.new(repository, user, protocol, redirected_path)
container_moved.add_message
end
def check_command_disabled!
if upload_pack?
check_upload_pack_disabled!
elsif receive_pack?
check_receive_pack_disabled!
end
end
def check_upload_pack_disabled!
if http? && upload_pack_disabled_over_http?
raise ForbiddenError, error_message(:upload_pack_disabled_over_http)
end
end
def check_receive_pack_disabled!
if http? && receive_pack_disabled_over_http?
raise ForbiddenError, error_message(:receive_pack_disabled_over_http)
end
end
def check_command_existence!
unless ALL_COMMANDS.include?(cmd)
raise ForbiddenError, error_message(:command_not_allowed)
end
end
def check_db_accessibility!
return unless receive_pack?
if Gitlab::Database.read_only?
raise ForbiddenError, push_to_read_only_message
end
end
def check_repository_existence!
raise NotFoundError, no_repo_message unless repository.exists?
end
def no_repo_message
error_message(:no_repo)
end
def check_download_access!
passed = deploy_key_can_download_code? ||
deploy_token? ||
user_can_download_code? ||
build_can_download_code? ||
guest_can_download_code?
unless passed
raise ForbiddenError, download_forbidden_message
end
end
def download_forbidden_message
error_message(:download)
end
def project?
# Strict nil check, to avoid any surprises with Object#present?
# which can delegate to #empty?
!project.nil?
end
def project
container if container.is_a?(::Project)
end
def check_push_access!
if project&.repository_read_only?
raise ForbiddenError, error_message(:read_only)
end
if deploy_key?
unless deploy_key.can_push_to?(project)
raise ForbiddenError, error_message(:deploy_key_upload)
end
elsif user
# User access is verified in check_change_access!
else
raise ForbiddenError, error_message(:upload)
end
check_change_access!
end
def user_can_push?
user_access.can_do_action?(push_ability)
end
def check_change_access!
if changes == ANY
can_push = deploy_key? ||
user_can_push? ||
project&.any_branch_allows_collaboration?(user_access.user)
unless can_push
raise ForbiddenError, error_message(:push_code)
end
else
# If there are worktrees with a HEAD pointing to a non-existent object,
# calls to `git rev-list --all` will fail in git 2.15+. This should also
# clear stale lock files.
project.repository.clean_stale_repository_files if project.present?
check_access!
end
end
def check_access!
Checks::ChangesAccess.new(
changes_list.changes,
user_access: user_access,
project: project,
protocol: protocol,
logger: logger
).validate!
rescue Checks::TimedLogger::TimeoutError
raise TimeoutError, logger.full_message
end
def deploy_key
actor if deploy_key?
end
def deploy_key?
actor.is_a?(DeployKey)
end
def deploy_token
actor if deploy_token?
end
def deploy_token?
actor.is_a?(DeployToken)
end
def ci?
actor == :ci
end
def key?
actor.is_a?(Key)
end
def can_read_project?
if deploy_key?
deploy_key.has_access_to?(project)
elsif deploy_token?
deploy_token.has_access_to?(project)
elsif user
user.can?(:read_project, project)
elsif ci?
true # allow CI (build without a user) for backwards compatibility
end || Guest.can?(:read_project, project)
end
def http?
protocol == 'http'
end
def ssh?
protocol == 'ssh'
end
def upload_pack?
cmd == 'git-upload-pack'
end
def receive_pack?
cmd == 'git-receive-pack'
end
def upload_pack_disabled_over_http?
!Gitlab.config.gitlab_shell.upload_pack
end
def receive_pack_disabled_over_http?
!Gitlab.config.gitlab_shell.receive_pack
end
protected
def error_message(key)
self.class.error_message(key)
end
def success_result
::Gitlab::GitAccessResult::Success.new(console_messages: check_for_console_messages)
end
def changes_list
@changes_list ||= Gitlab::ChangesList.new(changes == ANY ? [] : changes)
end
def user
strong_memoize(:user) do
case actor
when User
actor
when DeployKey
nil
when Key
actor.user
when :ci
nil
end
end
end
def user_access
@user_access ||= if ci?
CiAccess.new
elsif user && request_from_ci_build?
BuildAccess.new(user, container: container)
elsif deploy_key?
DeployKeyAccess.new(deploy_key, container: container)
else
UserAccess.new(user, container: container)
end
end
def push_to_read_only_message
error_message(:cannot_push_to_read_only)
end
def repository
container&.repository
end
def check_size_before_push!
if check_size_limit? && size_checker.above_size_limit?
raise ForbiddenError, size_checker.error_message.push_error
end
end
def check_push_size!
return unless check_size_limit?
# If there are worktrees with a HEAD pointing to a non-existent object,
# calls to `git rev-list --all` will fail in git 2.15+. This should also
# clear stale lock files.
repository.clean_stale_repository_files
# Use #check_repository_disk_size to get correct push size whenever a lot of changes
# gets pushed at the same time containing the same blobs. This is only
# doable if GIT_OBJECT_DIRECTORY_RELATIVE env var is set and happens
# when git push comes from CLI (not via UI and API).
#
# Fallback to determining push size using the changes_list so we can still
# determine the push size if env var isn't set (e.g. changes are made
# via UI and API).
if check_quarantine_size?
check_repository_disk_size
else
check_changes_size
end
end
def check_quarantine_size?
git_env = ::Gitlab::Git::HookEnv.all(repository.gl_repository)
git_env['GIT_OBJECT_DIRECTORY_RELATIVE'].present?
end
def check_repository_disk_size
check_size_against_limit(repository.object_directory_size)
end
def check_changes_size
changes_size = 0
changes_list.each do |change|
changes_size += repository.new_blobs(change[:newrev]).sum(&:size)
check_size_against_limit(changes_size)
end
end
def check_size_against_limit(size)
if size_checker.changes_will_exceed_size_limit?(size)
raise ForbiddenError, size_checker.error_message.new_changes_error
end
end
def check_size_limit?
strong_memoize(:check_size_limit) do
changes_list.any? { |change| !Gitlab::Git.blank_ref?(change[:newrev]) }
end
end
def size_checker
container.repository_size_checker
end
# overriden in EE
def check_additional_conditions!
end
end
end
Gitlab::GitAccess.prepend_mod_with('Gitlab::GitAccess')
|