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
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
|
require 'active_support/core_ext/hash/keys'
require 'active_support/core_ext/module/attribute_accessors'
require 'active_support/core_ext/object/blank'
require 'active_support/key_generator'
require 'active_support/message_verifier'
require 'active_support/json'
module ActionDispatch
class Request < Rack::Request
def cookie_jar
env['action_dispatch.cookies'] ||= Cookies::CookieJar.build(self)
end
end
# \Cookies are read and written through ActionController#cookies.
#
# The cookies being read are the ones received along with the request, the cookies
# being written will be sent out with the response. Reading a cookie does not get
# the cookie object itself back, just the value it holds.
#
# Examples of writing:
#
# # Sets a simple session cookie.
# # This cookie will be deleted when the user's browser is closed.
# cookies[:user_name] = "david"
#
# # Cookie values are String based. Other data types need to be serialized.
# cookies[:lat_lon] = JSON.generate([47.68, -122.37])
#
# # Sets a cookie that expires in 1 hour.
# cookies[:login] = { value: "XJ-122", expires: 1.hour.from_now }
#
# # Sets a signed cookie, which prevents users from tampering with its value.
# # The cookie is signed by your app's `secrets.secret_key_base` value.
# # It can be read using the signed method `cookies.signed[:name]`
# cookies.signed[:user_id] = current_user.id
#
# # Sets a "permanent" cookie (which expires in 20 years from now).
# cookies.permanent[:login] = "XJ-122"
#
# # You can also chain these methods:
# cookies.permanent.signed[:login] = "XJ-122"
#
# Examples of reading:
#
# cookies[:user_name] # => "david"
# cookies.size # => 2
# JSON.parse(cookies[:lat_lon]) # => [47.68, -122.37]
# cookies.signed[:login] # => "XJ-122"
#
# Example for deleting:
#
# cookies.delete :user_name
#
# Please note that if you specify a :domain when setting a cookie, you must also specify the domain when deleting the cookie:
#
# cookies[:name] = {
# value: 'a yummy cookie',
# expires: 1.year.from_now,
# domain: 'domain.com'
# }
#
# cookies.delete(:name, domain: 'domain.com')
#
# The option symbols for setting cookies are:
#
# * <tt>:value</tt> - The cookie's value.
# * <tt>:path</tt> - The path for which this cookie applies. Defaults to the root
# of the application.
# * <tt>:domain</tt> - The domain for which this cookie applies so you can
# restrict to the domain level. If you use a schema like www.example.com
# and want to share session with user.example.com set <tt>:domain</tt>
# to <tt>:all</tt>. Make sure to specify the <tt>:domain</tt> option with
# <tt>:all</tt> or <tt>Array</tt> again when deleting cookies.
#
# domain: nil # Does not set cookie domain. (default)
# domain: :all # Allow the cookie for the top most level
# # domain and subdomains.
# domain: %w(.example.com .example.org) # Allow the cookie
# # for concrete domain names.
#
# * <tt>:expires</tt> - The time at which this cookie expires, as a \Time object.
# * <tt>:secure</tt> - Whether this cookie is only transmitted to HTTPS servers.
# Default is +false+.
# * <tt>:httponly</tt> - Whether this cookie is accessible via scripting or
# only HTTP. Defaults to +false+.
class Cookies
HTTP_HEADER = "Set-Cookie".freeze
GENERATOR_KEY = "action_dispatch.key_generator".freeze
SIGNED_COOKIE_SALT = "action_dispatch.signed_cookie_salt".freeze
ENCRYPTED_COOKIE_SALT = "action_dispatch.encrypted_cookie_salt".freeze
ENCRYPTED_SIGNED_COOKIE_SALT = "action_dispatch.encrypted_signed_cookie_salt".freeze
SECRET_TOKEN = "action_dispatch.secret_token".freeze
SECRET_KEY_BASE = "action_dispatch.secret_key_base".freeze
COOKIES_SERIALIZER = "action_dispatch.cookies_serializer".freeze
COOKIES_DIGEST = "action_dispatch.cookies_digest".freeze
# Cookies can typically store 4096 bytes.
MAX_COOKIE_SIZE = 4096
# Raised when storing more than 4K of session data.
CookieOverflow = Class.new StandardError
# Include in a cookie jar to allow chaining, e.g. cookies.permanent.signed
module ChainedCookieJars
# Returns a jar that'll automatically set the assigned cookies to have an expiration date 20 years from now. Example:
#
# cookies.permanent[:prefers_open_id] = true
# # => Set-Cookie: prefers_open_id=true; path=/; expires=Sun, 16-Dec-2029 03:24:16 GMT
#
# This jar is only meant for writing. You'll read permanent cookies through the regular accessor.
#
# This jar allows chaining with the signed jar as well, so you can set permanent, signed cookies. Examples:
#
# cookies.permanent.signed[:remember_me] = current_user.id
# # => Set-Cookie: remember_me=BAhU--848956038e692d7046deab32b7131856ab20e14e; path=/; expires=Sun, 16-Dec-2029 03:24:16 GMT
def permanent
@permanent ||= PermanentCookieJar.new(self, @key_generator, @options)
end
# Returns a jar that'll automatically generate a signed representation of cookie value and verify it when reading from
# the cookie again. This is useful for creating cookies with values that the user is not supposed to change. If a signed
# cookie was tampered with by the user (or a 3rd party), nil will be returned.
#
# If +secrets.secret_key_base+ and +secrets.secret_token+ (deprecated) are both set,
# legacy cookies signed with the old key generator will be transparently upgraded.
#
# This jar requires that you set a suitable secret for the verification on your app's +secrets.secret_key_base+.
#
# Example:
#
# cookies.signed[:discount] = 45
# # => Set-Cookie: discount=BAhpMg==--2c1c6906c90a3bc4fd54a51ffb41dffa4bf6b5f7; path=/
#
# cookies.signed[:discount] # => 45
def signed
@signed ||=
if @options[:upgrade_legacy_signed_cookies]
UpgradeLegacySignedCookieJar.new(self, @key_generator, @options)
else
SignedCookieJar.new(self, @key_generator, @options)
end
end
# Returns a jar that'll automatically encrypt cookie values before sending them to the client and will decrypt them for read.
# If the cookie was tampered with by the user (or a 3rd party), nil will be returned.
#
# If +secrets.secret_key_base+ and +secrets.secret_token+ (deprecated) are both set,
# legacy cookies signed with the old key generator will be transparently upgraded.
#
# This jar requires that you set a suitable secret for the verification on your app's +secrets.secret_key_base+.
#
# Example:
#
# cookies.encrypted[:discount] = 45
# # => Set-Cookie: discount=ZS9ZZ1R4cG1pcUJ1bm80anhQang3dz09LS1mbDZDSU5scGdOT3ltQ2dTdlhSdWpRPT0%3D--ab54663c9f4e3bc340c790d6d2b71e92f5b60315; path=/
#
# cookies.encrypted[:discount] # => 45
def encrypted
@encrypted ||=
if @options[:upgrade_legacy_signed_cookies]
UpgradeLegacyEncryptedCookieJar.new(self, @key_generator, @options)
else
EncryptedCookieJar.new(self, @key_generator, @options)
end
end
# Returns the +signed+ or +encrypted+ jar, preferring +encrypted+ if +secret_key_base+ is set.
# Used by ActionDispatch::Session::CookieStore to avoid the need to introduce new cookie stores.
def signed_or_encrypted
@signed_or_encrypted ||=
if @options[:secret_key_base].present?
encrypted
else
signed
end
end
end
# Passing the ActiveSupport::MessageEncryptor::NullSerializer downstream
# to the Message{Encryptor,Verifier} allows us to handle the
# (de)serialization step within the cookie jar, which gives us the
# opportunity to detect and migrate legacy cookies.
module VerifyAndUpgradeLegacySignedMessage # :nodoc:
def initialize(*args)
super
@legacy_verifier = ActiveSupport::MessageVerifier.new(@options[:secret_token], serializer: ActiveSupport::MessageEncryptor::NullSerializer)
end
def verify_and_upgrade_legacy_signed_message(name, signed_message)
deserialize(name, @legacy_verifier.verify(signed_message)).tap do |value|
self[name] = { value: value }
end
rescue ActiveSupport::MessageVerifier::InvalidSignature
nil
end
end
class CookieJar #:nodoc:
include Enumerable, ChainedCookieJars
# This regular expression is used to split the levels of a domain.
# The top level domain can be any string without a period or
# **.**, ***.** style TLDs like co.uk or com.au
#
# www.example.co.uk gives:
# $& => example.co.uk
#
# example.com gives:
# $& => example.com
#
# lots.of.subdomains.example.local gives:
# $& => example.local
DOMAIN_REGEXP = /[^.]*\.([^.]*|..\...|...\...)$/
def self.options_for_env(env) #:nodoc:
{ signed_cookie_salt: env[SIGNED_COOKIE_SALT] || '',
encrypted_cookie_salt: env[ENCRYPTED_COOKIE_SALT] || '',
encrypted_signed_cookie_salt: env[ENCRYPTED_SIGNED_COOKIE_SALT] || '',
secret_token: env[SECRET_TOKEN],
secret_key_base: env[SECRET_KEY_BASE],
upgrade_legacy_signed_cookies: env[SECRET_TOKEN].present? && env[SECRET_KEY_BASE].present?,
serializer: env[COOKIES_SERIALIZER],
digest: env[COOKIES_DIGEST]
}
end
def self.build(request)
env = request.env
key_generator = env[GENERATOR_KEY]
options = options_for_env env
host = request.host
secure = request.ssl?
new(key_generator, host, secure, options).tap do |hash|
hash.update(request.cookies)
end
end
def initialize(key_generator, host = nil, secure = false, options = {})
@key_generator = key_generator
@set_cookies = {}
@delete_cookies = {}
@host = host
@secure = secure
@options = options
@cookies = {}
@committed = false
end
def committed?; @committed; end
def commit!
@committed = true
@set_cookies.freeze
@delete_cookies.freeze
end
def each(&block)
@cookies.each(&block)
end
# Returns the value of the cookie by +name+, or +nil+ if no such cookie exists.
def [](name)
@cookies[name.to_s]
end
def fetch(name, *args, &block)
@cookies.fetch(name.to_s, *args, &block)
end
def key?(name)
@cookies.key?(name.to_s)
end
alias :has_key? :key?
def update(other_hash)
@cookies.update other_hash.stringify_keys
self
end
def handle_options(options) #:nodoc:
options[:path] ||= "/"
if options[:domain] == :all || options[:domain] == 'all'
# if there is a provided tld length then we use it otherwise default domain regexp
domain_regexp = options[:tld_length] ? /([^.]+\.?){#{options[:tld_length]}}$/ : DOMAIN_REGEXP
# if host is not ip and matches domain regexp
# (ip confirms to domain regexp so we explicitly check for ip)
options[:domain] = if (@host !~ /^[\d.]+$/) && (@host =~ domain_regexp)
".#{$&}"
end
elsif options[:domain].is_a? Array
# if host matches one of the supplied domains without a dot in front of it
options[:domain] = options[:domain].find {|domain| @host.include? domain.sub(/^\./, '') }
end
end
# Sets the cookie named +name+. The second argument may be the cookie's
# value or a hash of options as documented above.
def []=(name, options)
if options.is_a?(Hash)
options.symbolize_keys!
value = options[:value]
else
value = options
options = { :value => value }
end
handle_options(options)
if @cookies[name.to_s] != value or options[:expires]
@cookies[name.to_s] = value
@set_cookies[name.to_s] = options
@delete_cookies.delete(name.to_s)
end
value
end
# Removes the cookie on the client machine by setting the value to an empty string
# and the expiration date in the past. Like <tt>[]=</tt>, you can pass in
# an options hash to delete cookies with extra data such as a <tt>:path</tt>.
def delete(name, options = {})
return unless @cookies.has_key? name.to_s
options.symbolize_keys!
handle_options(options)
value = @cookies.delete(name.to_s)
@delete_cookies[name.to_s] = options
value
end
# Whether the given cookie is to be deleted by this CookieJar.
# Like <tt>[]=</tt>, you can pass in an options hash to test if a
# deletion applies to a specific <tt>:path</tt>, <tt>:domain</tt> etc.
def deleted?(name, options = {})
options.symbolize_keys!
handle_options(options)
@delete_cookies[name.to_s] == options
end
# Removes all cookies on the client machine by calling <tt>delete</tt> for each cookie
def clear(options = {})
@cookies.each_key{ |k| delete(k, options) }
end
def write(headers)
@set_cookies.each { |k, v| ::Rack::Utils.set_cookie_header!(headers, k, v) if write_cookie?(v) }
@delete_cookies.each { |k, v| ::Rack::Utils.delete_cookie_header!(headers, k, v) }
end
def recycle! #:nodoc:
@set_cookies = {}
@delete_cookies = {}
end
mattr_accessor :always_write_cookie
self.always_write_cookie = false
private
def write_cookie?(cookie)
@secure || !cookie[:secure] || always_write_cookie
end
end
class PermanentCookieJar #:nodoc:
include ChainedCookieJars
def initialize(parent_jar, key_generator, options = {})
@parent_jar = parent_jar
@key_generator = key_generator
@options = options
end
def [](name)
@parent_jar[name.to_s]
end
def []=(name, options)
if options.is_a?(Hash)
options.symbolize_keys!
else
options = { :value => options }
end
options[:expires] = 20.years.from_now
@parent_jar[name] = options
end
end
class JsonSerializer # :nodoc:
def self.load(value)
ActiveSupport::JSON.decode(value)
end
def self.dump(value)
ActiveSupport::JSON.encode(value)
end
end
module SerializedCookieJars # :nodoc:
MARSHAL_SIGNATURE = "\x04\x08".freeze
protected
def needs_migration?(value)
@options[:serializer] == :hybrid && value.start_with?(MARSHAL_SIGNATURE)
end
def serialize(value)
serializer.dump(value)
end
def deserialize(name, value)
if value
if needs_migration?(value)
Marshal.load(value).tap do |v|
self[name] = { value: v }
end
else
serializer.load(value)
end
end
end
def serializer
serializer = @options[:serializer] || :marshal
case serializer
when :marshal
Marshal
when :json, :hybrid
JsonSerializer
else
serializer
end
end
def digest
@options[:digest] || 'SHA1'
end
end
class SignedCookieJar #:nodoc:
include ChainedCookieJars
include SerializedCookieJars
def initialize(parent_jar, key_generator, options = {})
@parent_jar = parent_jar
@options = options
secret = key_generator.generate_key(@options[:signed_cookie_salt])
@verifier = ActiveSupport::MessageVerifier.new(secret, digest: digest, serializer: ActiveSupport::MessageEncryptor::NullSerializer)
end
# Returns the value of the cookie by +name+ if it is untampered,
# returns +nil+ otherwise or if no such cookie exists.
def [](name)
if signed_message = @parent_jar[name]
deserialize name, verify(signed_message)
end
end
# Signs and Sets the cookie named +name+. The second argument may be the cookie's
# value or a hash of options as documented above.
def []=(name, options)
if options.is_a?(Hash)
options.symbolize_keys!
options[:value] = @verifier.generate(serialize(options[:value]))
else
options = { :value => @verifier.generate(serialize(options)) }
end
raise CookieOverflow if options[:value].bytesize > MAX_COOKIE_SIZE
@parent_jar[name] = options
end
private
def verify(signed_message)
@verifier.verify(signed_message)
rescue ActiveSupport::MessageVerifier::InvalidSignature
nil
end
end
# UpgradeLegacySignedCookieJar is used instead of SignedCookieJar if
# secrets.secret_token and secrets.secret_key_base are both set. It reads
# legacy cookies signed with the old dummy key generator and signs and
# re-saves them using the new key generator to provide a smooth upgrade path.
class UpgradeLegacySignedCookieJar < SignedCookieJar #:nodoc:
include VerifyAndUpgradeLegacySignedMessage
def [](name)
if signed_message = @parent_jar[name]
deserialize(name, verify(signed_message)) || verify_and_upgrade_legacy_signed_message(name, signed_message)
end
end
end
class EncryptedCookieJar #:nodoc:
include ChainedCookieJars
include SerializedCookieJars
def initialize(parent_jar, key_generator, options = {})
if ActiveSupport::LegacyKeyGenerator === key_generator
raise "You didn't set secrets.secret_key_base, which is required for this cookie jar. " +
"Read the upgrade documentation to learn more about this new config option."
end
@parent_jar = parent_jar
@options = options
secret = key_generator.generate_key(@options[:encrypted_cookie_salt])
sign_secret = key_generator.generate_key(@options[:encrypted_signed_cookie_salt])
@encryptor = ActiveSupport::MessageEncryptor.new(secret, sign_secret, digest: digest, serializer: ActiveSupport::MessageEncryptor::NullSerializer)
end
# Returns the value of the cookie by +name+ if it is untampered,
# returns +nil+ otherwise or if no such cookie exists.
def [](name)
if encrypted_message = @parent_jar[name]
deserialize name, decrypt_and_verify(encrypted_message)
end
end
# Encrypts and Sets the cookie named +name+. The second argument may be the cookie's
# value or a hash of options as documented above.
def []=(name, options)
if options.is_a?(Hash)
options.symbolize_keys!
else
options = { :value => options }
end
options[:value] = @encryptor.encrypt_and_sign(serialize(options[:value]))
raise CookieOverflow if options[:value].bytesize > MAX_COOKIE_SIZE
@parent_jar[name] = options
end
private
def decrypt_and_verify(encrypted_message)
@encryptor.decrypt_and_verify(encrypted_message)
rescue ActiveSupport::MessageVerifier::InvalidSignature, ActiveSupport::MessageEncryptor::InvalidMessage
nil
end
end
# UpgradeLegacyEncryptedCookieJar is used by ActionDispatch::Session::CookieStore
# instead of EncryptedCookieJar if secrets.secret_token and secrets.secret_key_base
# are both set. It reads legacy cookies signed with the old dummy key generator and
# encrypts and re-saves them using the new key generator to provide a smooth upgrade path.
class UpgradeLegacyEncryptedCookieJar < EncryptedCookieJar #:nodoc:
include VerifyAndUpgradeLegacySignedMessage
def [](name)
if encrypted_or_signed_message = @parent_jar[name]
deserialize(name, decrypt_and_verify(encrypted_or_signed_message)) || verify_and_upgrade_legacy_signed_message(name, encrypted_or_signed_message)
end
end
end
def initialize(app)
@app = app
end
def call(env)
status, headers, body = @app.call(env)
if cookie_jar = env['action_dispatch.cookies']
unless cookie_jar.committed?
cookie_jar.write(headers)
if headers[HTTP_HEADER].respond_to?(:join)
headers[HTTP_HEADER] = headers[HTTP_HEADER].join("\n")
end
end
end
[status, headers, body]
end
end
end
|