--- /dev/null
+module ActionController
+ module HttpAuthentication
+ # Makes it dead easy to do HTTP Basic authentication.
+ #
+ # Simple Basic example:
+ #
+ # class PostsController < ApplicationController
+ # USER_NAME, PASSWORD = "dhh", "secret"
+ #
+ # before_filter :authenticate, :except => [ :index ]
+ #
+ # def index
+ # render :text => "Everyone can see me!"
+ # end
+ #
+ # def edit
+ # render :text => "I'm only accessible if you know the password"
+ # end
+ #
+ # private
+ # def authenticate
+ # authenticate_or_request_with_http_basic do |user_name, password|
+ # user_name == USER_NAME && password == PASSWORD
+ # end
+ # end
+ # end
+ #
+ #
+ # Here is a more advanced Basic example where only Atom feeds and the XML API is protected by HTTP authentication,
+ # the regular HTML interface is protected by a session approach:
+ #
+ # class ApplicationController < ActionController::Base
+ # before_filter :set_account, :authenticate
+ #
+ # protected
+ # def set_account
+ # @account = Account.find_by_url_name(request.subdomains.first)
+ # end
+ #
+ # def authenticate
+ # case request.format
+ # when Mime::XML, Mime::ATOM
+ # if user = authenticate_with_http_basic { |u, p| @account.users.authenticate(u, p) }
+ # @current_user = user
+ # else
+ # request_http_basic_authentication
+ # end
+ # else
+ # if session_authenticated?
+ # @current_user = @account.users.find(session[:authenticated][:user_id])
+ # else
+ # redirect_to(login_url) and return false
+ # end
+ # end
+ # end
+ # end
+ #
+ # In your integration tests, you can do something like this:
+ #
+ # def test_access_granted_from_xml
+ # get(
+ # "/notes/1.xml", nil,
+ # :authorization => ActionController::HttpAuthentication::Basic.encode_credentials(users(:dhh).name, users(:dhh).password)
+ # )
+ #
+ # assert_equal 200, status
+ # end
+ #
+ # Simple Digest example:
+ #
+ # require 'digest/md5'
+ # class PostsController < ApplicationController
+ # REALM = "SuperSecret"
+ # USERS = {"dhh" => "secret", #plain text password
+ # "dap" => Digest:MD5::hexdigest(["dap",REALM,"secret"].join(":")) #ha1 digest password
+ #
+ # before_filter :authenticate, :except => [:index]
+ #
+ # def index
+ # render :text => "Everyone can see me!"
+ # end
+ #
+ # def edit
+ # render :text => "I'm only accessible if you know the password"
+ # end
+ #
+ # private
+ # def authenticate
+ # authenticate_or_request_with_http_digest(REALM) do |username|
+ # USERS[username]
+ # end
+ # end
+ # end
+ #
+ # NOTE: The +authenticate_or_request_with_http_digest+ block must return the user's password or the ha1 digest hash so the framework can appropriately
+ # hash to check the user's credentials. Returning +nil+ will cause authentication to fail.
+ # Storing the ha1 hash: MD5(username:realm:password), is better than storing a plain password. If
+ # the password file or database is compromised, the attacker would be able to use the ha1 hash to
+ # authenticate as the user at this +realm+, but would not have the user's password to try using at
+ # other sites.
+ #
+ # On shared hosts, Apache sometimes doesn't pass authentication headers to
+ # FCGI instances. If your environment matches this description and you cannot
+ # authenticate, try this rule in your Apache setup:
+ #
+ # RewriteRule ^(.*)$ dispatch.fcgi [E=X-HTTP_AUTHORIZATION:%{HTTP:Authorization},QSA,L]
+ module Basic
+ extend self
+
+ module ControllerMethods
+ def authenticate_or_request_with_http_basic(realm = "Application", &login_procedure)
+ authenticate_with_http_basic(&login_procedure) || request_http_basic_authentication(realm)
+ end
+
+ def authenticate_with_http_basic(&login_procedure)
+ HttpAuthentication::Basic.authenticate(self, &login_procedure)
+ end
+
+ def request_http_basic_authentication(realm = "Application")
+ HttpAuthentication::Basic.authentication_request(self, realm)
+ end
+ end
+
+ def authenticate(controller, &login_procedure)
+ unless authorization(controller.request).blank?
+ login_procedure.call(*user_name_and_password(controller.request))
+ end
+ end
+
+ def user_name_and_password(request)
+ decode_credentials(request).split(/:/, 2)
+ end
+
+ def authorization(request)
+ request.env['HTTP_AUTHORIZATION'] ||
+ request.env['X-HTTP_AUTHORIZATION'] ||
+ request.env['X_HTTP_AUTHORIZATION'] ||
+ request.env['REDIRECT_X_HTTP_AUTHORIZATION']
+ end
+
+ def decode_credentials(request)
+ ActiveSupport::Base64.decode64(authorization(request).split.last || '')
+ end
+
+ def encode_credentials(user_name, password)
+ "Basic #{ActiveSupport::Base64.encode64("#{user_name}:#{password}")}"
+ end
+
+ def authentication_request(controller, realm)
+ controller.headers["WWW-Authenticate"] = %(Basic realm="#{realm.gsub(/"/, "")}")
+ controller.__send__ :render, :text => "HTTP Basic: Access denied.\n", :status => :unauthorized
+ end
+ end
+
+ module Digest
+ extend self
+
+ module ControllerMethods
+ def authenticate_or_request_with_http_digest(realm = "Application", &password_procedure)
+ authenticate_with_http_digest(realm, &password_procedure) || request_http_digest_authentication(realm)
+ end
+
+ # Authenticate with HTTP Digest, returns true or false
+ def authenticate_with_http_digest(realm = "Application", &password_procedure)
+ HttpAuthentication::Digest.authenticate(self, realm, &password_procedure)
+ end
+
+ # Render output including the HTTP Digest authentication header
+ def request_http_digest_authentication(realm = "Application", message = nil)
+ HttpAuthentication::Digest.authentication_request(self, realm, message)
+ end
+ end
+
+ # Returns false on a valid response, true otherwise
+ def authenticate(controller, realm, &password_procedure)
+ authorization(controller.request) && validate_digest_response(controller.request, realm, &password_procedure)
+ end
+
+ def authorization(request)
+ request.env['HTTP_AUTHORIZATION'] ||
+ request.env['X-HTTP_AUTHORIZATION'] ||
+ request.env['X_HTTP_AUTHORIZATION'] ||
+ request.env['REDIRECT_X_HTTP_AUTHORIZATION']
+ end
+
+ # Raises error unless the request credentials response value matches the expected value.
+ # First try the password as a ha1 digest password. If this fails, then try it as a plain
+ # text password.
+ def validate_digest_response(request, realm, &password_procedure)
+ credentials = decode_credentials_header(request)
+ valid_nonce = validate_nonce(request, credentials[:nonce])
+
+ if valid_nonce && realm == credentials[:realm] && opaque == credentials[:opaque]
+ password = password_procedure.call(credentials[:username])
+
+ [true, false].any? do |password_is_ha1|
+ expected = expected_response(request.env['REQUEST_METHOD'], request.env['REQUEST_URI'], credentials, password, password_is_ha1)
+ expected == credentials[:response]
+ end
+ end
+ end
+
+ # Returns the expected response for a request of +http_method+ to +uri+ with the decoded +credentials+ and the expected +password+
+ # Optional parameter +password_is_ha1+ is set to +true+ by default, since best practice is to store ha1 digest instead
+ # of a plain-text password.
+ def expected_response(http_method, uri, credentials, password, password_is_ha1=true)
+ ha1 = password_is_ha1 ? password : ha1(credentials, password)
+ ha2 = ::Digest::MD5.hexdigest([http_method.to_s.upcase, uri].join(':'))
+ ::Digest::MD5.hexdigest([ha1, credentials[:nonce], credentials[:nc], credentials[:cnonce], credentials[:qop], ha2].join(':'))
+ end
+
+ def ha1(credentials, password)
+ ::Digest::MD5.hexdigest([credentials[:username], credentials[:realm], password].join(':'))
+ end
+
+ def encode_credentials(http_method, credentials, password, password_is_ha1)
+ credentials[:response] = expected_response(http_method, credentials[:uri], credentials, password, password_is_ha1)
+ "Digest " + credentials.sort_by {|x| x[0].to_s }.inject([]) {|a, v| a << "#{v[0]}='#{v[1]}'" }.join(', ')
+ end
+
+ def decode_credentials_header(request)
+ decode_credentials(authorization(request))
+ end
+
+ def decode_credentials(header)
+ header.to_s.gsub(/^Digest\s+/,'').split(',').inject({}) do |hash, pair|
+ key, value = pair.split('=', 2)
+ hash[key.strip.to_sym] = value.to_s.gsub(/^"|"$/,'').gsub(/'/, '')
+ hash
+ end
+ end
+
+ def authentication_header(controller, realm)
+ controller.headers["WWW-Authenticate"] = %(Digest realm="#{realm}", qop="auth", algorithm=MD5, nonce="#{nonce}", opaque="#{opaque}")
+ end
+
+ def authentication_request(controller, realm, message = nil)
+ message ||= "HTTP Digest: Access denied.\n"
+ authentication_header(controller, realm)
+ controller.__send__ :render, :text => message, :status => :unauthorized
+ end
+
+ # Uses an MD5 digest based on time to generate a value to be used only once.
+ #
+ # A server-specified data string which should be uniquely generated each time a 401 response is made.
+ # It is recommended that this string be base64 or hexadecimal data.
+ # Specifically, since the string is passed in the header lines as a quoted string, the double-quote character is not allowed.
+ #
+ # The contents of the nonce are implementation dependent.
+ # The quality of the implementation depends on a good choice.
+ # A nonce might, for example, be constructed as the base 64 encoding of
+ #
+ # => time-stamp H(time-stamp ":" ETag ":" private-key)
+ #
+ # where time-stamp is a server-generated time or other non-repeating value,
+ # ETag is the value of the HTTP ETag header associated with the requested entity,
+ # and private-key is data known only to the server.
+ # With a nonce of this form a server would recalculate the hash portion after receiving the client authentication header and
+ # reject the request if it did not match the nonce from that header or
+ # if the time-stamp value is not recent enough. In this way the server can limit the time of the nonce's validity.
+ # The inclusion of the ETag prevents a replay request for an updated version of the resource.
+ # (Note: including the IP address of the client in the nonce would appear to offer the server the ability
+ # to limit the reuse of the nonce to the same client that originally got it.
+ # However, that would break proxy farms, where requests from a single user often go through different proxies in the farm.
+ # Also, IP address spoofing is not that hard.)
+ #
+ # An implementation might choose not to accept a previously used nonce or a previously used digest, in order to
+ # protect against a replay attack. Or, an implementation might choose to use one-time nonces or digests for
+ # POST or PUT requests and a time-stamp for GET requests. For more details on the issues involved see Section 4
+ # of this document.
+ #
+ # The nonce is opaque to the client. Composed of Time, and hash of Time with secret
+ # key from the Rails session secret generated upon creation of project. Ensures
+ # the time cannot be modifed by client.
+ def nonce(time = Time.now)
+ t = time.to_i
+ hashed = [t, secret_key]
+ digest = ::Digest::MD5.hexdigest(hashed.join(":"))
+ Base64.encode64("#{t}:#{digest}").gsub("\n", '')
+ end
+
+ # Might want a shorter timeout depending on whether the request
+ # is a PUT or POST, and if client is browser or web service.
+ # Can be much shorter if the Stale directive is implemented. This would
+ # allow a user to use new nonce without prompting user again for their
+ # username and password.
+ def validate_nonce(request, value, seconds_to_timeout=5*60)
+ t = Base64.decode64(value).split(":").first.to_i
+ nonce(t) == value && (t - Time.now.to_i).abs <= seconds_to_timeout
+ end
+
+ # Opaque based on random generation - but changing each request?
+ def opaque()
+ ::Digest::MD5.hexdigest(secret_key)
+ end
+
+ # Set in /initializers/session_store.rb, and loaded even if sessions are not in use.
+ def secret_key
+ ActionController::Base.session_options[:secret]
+ end
+
+ end
+ end
+end
projects / feedcatcher.git / blobdiff