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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, cookies)
end
def key_generator
env[Cookies::GENERATOR_KEY]
end
def signed_cookie_salt
env[Cookies::SIGNED_COOKIE_SALT]
end
def encrypted_cookie_salt
env[Cookies::ENCRYPTED_COOKIE_SALT]
end
def encrypted_signed_cookie_salt
env[Cookies::ENCRYPTED_SIGNED_COOKIE_SALT]
end
def secret_token
env[Cookies::SECRET_TOKEN]
end
def secret_key_base
env[Cookies::SECRET_KEY_BASE]
end
def cookies_serializer
env[Cookies::COOKIES_SERIALIZER]
end
def cookies_digest
env[Cookies::COOKIES_DIGEST]
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>:tld_length</tt> - When using <tt>:domain => :all</tt>, this option can be used to explicitly
# set the TLD length when using a short (<= 3 character) domain that is being interpreted as part of a TLD.
# For example, to share cookies between user1.lvh.me and user2.lvh.me, set <tt>:tld_length</tt> to 1.
# * <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, @request)
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 upgrade_legacy_signed_cookies?
UpgradeLegacySignedCookieJar.new(self, @request)
else
SignedCookieJar.new(self, @request)
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 upgrade_legacy_signed_cookies?
UpgradeLegacyEncryptedCookieJar.new(self, @request)
else
EncryptedCookieJar.new(self, @request)
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 @request.secret_key_base.present?
encrypted
else
signed
end
end
private
def upgrade_legacy_signed_cookies?
@request.secret_token.present? && @request.secret_key_base.present?
end
def key_generator
@request.key_generator
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(@request.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.build(req, cookies)
new(req).tap do |hash|
hash.update(cookies)
end
end
def initialize(request)
@set_cookies = {}
@delete_cookies = {}
@request = request
@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 to_header
@cookies.map { |k,v| "#{k}=#{v}" }.join ';'
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]}}$/ : DOMAIN_REGEXP
# if host is not ip and matches domain regexp
# (ip confirms to domain regexp so we explicitly check for ip)
options[:domain] = if (@request.host !~ /^[\d.]+$/) && (@request.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| @request.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)
@request.ssl? || !cookie[:secure] || always_write_cookie
end
end
class PermanentCookieJar #:nodoc:
include ChainedCookieJars
def initialize(parent_jar, request)
@parent_jar = parent_jar
@request = request
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)
@request.cookies_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 = @request.cookies_serializer || :marshal
case serializer
when :marshal
Marshal
when :json, :hybrid
JsonSerializer
else
serializer
end
end
def digest
@request.cookies_digest || 'SHA1'
end
end
class SignedCookieJar #:nodoc:
include ChainedCookieJars
include SerializedCookieJars
def initialize(parent_jar, request)
@parent_jar = parent_jar
@request = request
secret = key_generator.generate_key(request.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, request)
@request = request
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
secret = key_generator.generate_key(request.encrypted_cookie_salt || '')
sign_secret = key_generator.generate_key(request.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
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