mirror of
https://github.com/rails/rails.git
synced 2022-11-09 12:12:34 -05:00
224 lines
8.2 KiB
Ruby
224 lines
8.2 KiB
Ruby
module ActionController
|
|
module Session
|
|
# This cookie-based session store is the Rails default. Sessions typically
|
|
# contain at most a user_id and flash message; both fit within the 4K cookie
|
|
# size limit. Cookie-based sessions are dramatically faster than the
|
|
# alternatives.
|
|
#
|
|
# If you have more than 4K of session data or don't want your data to be
|
|
# visible to the user, pick another session store.
|
|
#
|
|
# CookieOverflow is raised if you attempt to store more than 4K of data.
|
|
#
|
|
# A message digest is included with the cookie to ensure data integrity:
|
|
# a user cannot alter his +user_id+ without knowing the secret key
|
|
# included in the hash. New apps are generated with a pregenerated secret
|
|
# in config/environment.rb. Set your own for old apps you're upgrading.
|
|
#
|
|
# Session options:
|
|
#
|
|
# * <tt>:secret</tt>: An application-wide key string or block returning a
|
|
# string called per generated digest. The block is called with the
|
|
# CGI::Session instance as an argument. It's important that the secret
|
|
# is not vulnerable to a dictionary attack. Therefore, you should choose
|
|
# a secret consisting of random numbers and letters and more than 30
|
|
# characters. Examples:
|
|
#
|
|
# :secret => '449fe2e7daee471bffae2fd8dc02313d'
|
|
# :secret => Proc.new { User.current_user.secret_key }
|
|
#
|
|
# * <tt>:digest</tt>: The message digest algorithm used to verify session
|
|
# integrity defaults to 'SHA1' but may be any digest provided by OpenSSL,
|
|
# such as 'MD5', 'RIPEMD160', 'SHA256', etc.
|
|
#
|
|
# To generate a secret key for an existing application, run
|
|
# "rake secret" and set the key in config/environment.rb.
|
|
#
|
|
# Note that changing digest or secret invalidates all existing sessions!
|
|
class CookieStore
|
|
# Cookies can typically store 4096 bytes.
|
|
MAX = 4096
|
|
SECRET_MIN_LENGTH = 30 # characters
|
|
|
|
DEFAULT_OPTIONS = {
|
|
:key => '_session_id',
|
|
:domain => nil,
|
|
:path => "/",
|
|
:expire_after => nil,
|
|
:httponly => true
|
|
}.freeze
|
|
|
|
ENV_SESSION_KEY = "rack.session".freeze
|
|
ENV_SESSION_OPTIONS_KEY = "rack.session.options".freeze
|
|
HTTP_SET_COOKIE = "Set-Cookie".freeze
|
|
|
|
# Raised when storing more than 4K of session data.
|
|
class CookieOverflow < StandardError; end
|
|
|
|
def initialize(app, options = {})
|
|
# Process legacy CGI options
|
|
options = options.symbolize_keys
|
|
if options.has_key?(:session_path)
|
|
options[:path] = options.delete(:session_path)
|
|
end
|
|
if options.has_key?(:session_key)
|
|
options[:key] = options.delete(:session_key)
|
|
end
|
|
if options.has_key?(:session_http_only)
|
|
options[:httponly] = options.delete(:session_http_only)
|
|
end
|
|
|
|
@app = app
|
|
|
|
# The session_key option is required.
|
|
ensure_session_key(options[:key])
|
|
@key = options.delete(:key).freeze
|
|
|
|
# The secret option is required.
|
|
ensure_secret_secure(options[:secret])
|
|
@secret = options.delete(:secret).freeze
|
|
|
|
@digest = options.delete(:digest) || 'SHA1'
|
|
@verifier = verifier_for(@secret, @digest)
|
|
|
|
@default_options = DEFAULT_OPTIONS.merge(options).freeze
|
|
|
|
freeze
|
|
end
|
|
|
|
def call(env)
|
|
env[ENV_SESSION_KEY] = AbstractStore::SessionHash.new(self, env)
|
|
env[ENV_SESSION_OPTIONS_KEY] = @default_options.dup
|
|
|
|
status, headers, body = @app.call(env)
|
|
|
|
session_data = env[ENV_SESSION_KEY]
|
|
options = env[ENV_SESSION_OPTIONS_KEY]
|
|
|
|
if !session_data.is_a?(AbstractStore::SessionHash) || session_data.send(:loaded?) || options[:expire_after]
|
|
session_data.send(:load!) if session_data.is_a?(AbstractStore::SessionHash) && !session_data.send(:loaded?)
|
|
session_data = marshal(session_data.to_hash)
|
|
|
|
raise CookieOverflow if session_data.size > MAX
|
|
|
|
cookie = Hash.new
|
|
cookie[:value] = session_data
|
|
unless options[:expire_after].nil?
|
|
cookie[:expires] = Time.now + options[:expire_after]
|
|
end
|
|
|
|
cookie = build_cookie(@key, cookie.merge(options))
|
|
case headers[HTTP_SET_COOKIE]
|
|
when Array
|
|
headers[HTTP_SET_COOKIE] << cookie
|
|
when String
|
|
headers[HTTP_SET_COOKIE] = [headers[HTTP_SET_COOKIE], cookie]
|
|
when nil
|
|
headers[HTTP_SET_COOKIE] = cookie
|
|
end
|
|
end
|
|
|
|
[status, headers, body]
|
|
end
|
|
|
|
private
|
|
# Should be in Rack::Utils soon
|
|
def build_cookie(key, value)
|
|
case value
|
|
when Hash
|
|
domain = "; domain=" + value[:domain] if value[:domain]
|
|
path = "; path=" + value[:path] if value[:path]
|
|
# According to RFC 2109, we need dashes here.
|
|
# N.B.: cgi.rb uses spaces...
|
|
expires = "; expires=" + value[:expires].clone.gmtime.
|
|
strftime("%a, %d-%b-%Y %H:%M:%S GMT") if value[:expires]
|
|
secure = "; secure" if value[:secure]
|
|
httponly = "; HttpOnly" if value[:httponly]
|
|
value = value[:value]
|
|
end
|
|
value = [value] unless Array === value
|
|
cookie = Rack::Utils.escape(key) + "=" +
|
|
value.map { |v| Rack::Utils.escape(v) }.join("&") +
|
|
"#{domain}#{path}#{expires}#{secure}#{httponly}"
|
|
end
|
|
|
|
def load_session(env)
|
|
request = Rack::Request.new(env)
|
|
session_data = request.cookies[@key]
|
|
data = unmarshal(session_data) || persistent_session_id!({})
|
|
[data[:session_id], data]
|
|
end
|
|
|
|
# Marshal a session hash into safe cookie data. Include an integrity hash.
|
|
def marshal(session)
|
|
@verifier.generate(persistent_session_id!(session))
|
|
end
|
|
|
|
# Unmarshal cookie data to a hash and verify its integrity.
|
|
def unmarshal(cookie)
|
|
persistent_session_id!(@verifier.verify(cookie)) if cookie
|
|
rescue ActiveSupport::MessageVerifier::InvalidSignature
|
|
nil
|
|
end
|
|
|
|
def ensure_session_key(key)
|
|
if key.blank?
|
|
raise ArgumentError, 'A key is required to write a ' +
|
|
'cookie containing the session data. Use ' +
|
|
'config.action_controller.session = { :key => ' +
|
|
'"_myapp_session", :secret => "some secret phrase" } in ' +
|
|
'config/environment.rb'
|
|
end
|
|
end
|
|
|
|
# To prevent users from using something insecure like "Password" we make sure that the
|
|
# secret they've provided is at least 30 characters in length.
|
|
def ensure_secret_secure(secret)
|
|
# There's no way we can do this check if they've provided a proc for the
|
|
# secret.
|
|
return true if secret.is_a?(Proc)
|
|
|
|
if secret.blank?
|
|
raise ArgumentError, "A secret is required to generate an " +
|
|
"integrity hash for cookie session data. Use " +
|
|
"config.action_controller.session = { :key => " +
|
|
"\"_myapp_session\", :secret => \"some secret phrase of at " +
|
|
"least #{SECRET_MIN_LENGTH} characters\" } " +
|
|
"in config/environment.rb"
|
|
end
|
|
|
|
if secret.length < SECRET_MIN_LENGTH
|
|
raise ArgumentError, "Secret should be something secure, " +
|
|
"like \"#{ActiveSupport::SecureRandom.hex(16)}\". The value you " +
|
|
"provided, \"#{secret}\", is shorter than the minimum length " +
|
|
"of #{SECRET_MIN_LENGTH} characters"
|
|
end
|
|
end
|
|
|
|
def verifier_for(secret, digest)
|
|
key = secret.respond_to?(:call) ? secret.call : secret
|
|
ActiveSupport::MessageVerifier.new(key, digest)
|
|
end
|
|
|
|
def generate_sid
|
|
ActiveSupport::SecureRandom.hex(16)
|
|
end
|
|
|
|
def persistent_session_id!(data)
|
|
(data ||= {}).merge!(inject_persistent_session_id(data))
|
|
end
|
|
|
|
def inject_persistent_session_id(data)
|
|
requires_session_id?(data) ? { :session_id => generate_sid } : {}
|
|
end
|
|
|
|
def requires_session_id?(data)
|
|
if data
|
|
data.respond_to?(:key?) && !data.key?(:session_id)
|
|
else
|
|
true
|
|
end
|
|
end
|
|
end
|
|
end
|
|
end
|