cirrusidentity/simplesamlphp-module-authoauth2

SSP Module for Oauth2 authentication sources


Keywords
oauth2, simplesamlphp, oidc
License
LGPL-2.1-only

Documentation

Table of Contents generated with DocToc

Build Status SimpleSAMLphp OAuth2 Authentication Source Module

This is a generic module for authentication against an OAuth2 or OIDC server. It performs the authorization_code flow and then uses the resulting access token to query an endpoint to get the user's attributes. It is a wrapper around the excellent PHP League OAuth2 Client.

Installation

The module can be installed with composer.

composer require cirrusidentity/simplesamlphp-module-authoauth2

Or you can install the latest from master

composer require cirrusidentity/simplesamlphp-module-authoauth2:dev-master

If you install into a tar ball distribution of SSP then composer, by default, will also install all dev dependencies for SSP and this module. This can be a long list. If you prefer not having dev dependencies installed, then you can use.

composer require --no-update cirrusidentity/simplesamlphp-module-authoauth2 && composer update --no-dev cirrusidentity/simplesamlphp-module-authoauth2

Changelog

View the change log

Usage

The generic OAuth2 client is configured with

  • the OAuth2 server endpoints
  • the client secret/id
  • optional parameters for scope
  • optional query parameters for the authorization url

Redirect URI

Almost all OAuth2/OIDC providers will require you to register a redirect URI. Use a url of the form below, and set hostname, SSP_PATH and optionally port to the correct values.

https://hostname/SSP_PATH/module.php/authoauth2/linkback.php

Provider specific Tips

Generic Usage

Generic usage provides enough configuration parameters to use with any OAuth2 or OIDC server.

       'oauth2' => array(
              'authoauth2:OAuth2',
              // *** Required for all integrations ***
              'urlAuthorize' => 'https://www.example.com/oauth2/authorize',
              'urlAccessToken' => 'https://www.example.com/oauth2/token',
              'urlResourceOwnerDetails' => 'https://api.example.com/userinfo',
              // You can add query params directly to urlResourceOwnerDetails or use urlResourceOwnerOptions.
              'urlResourceOwnerOptions' => [
                 'fields' => 'id,name,first_name,last_name,email'
              ],
              // allow fields from token response to be query params on resource owne details request
              'tokenFieldsToUserDetailsUrl' => [
                   'fieldName' => 'queryParamName',
                   'access_token' => 'access_token',
                   'user_id' > 'user_id',
              ],
              // *** Required for most integrations ***
              // Test App.
              'clientId' => '133972730583345',
              'clientSecret' => '36aefb235314bad5df075363b79cbbcd',
              // *** Optional ***
              // Custom query parameters to add to authorize request
              'urlAuthorizeOptions' => [
                  'prompt' => 'always',
              ],
              // Scopes to request
              'scopes' = ['email', 'profile'],
              'scopeSeparator' => ' ',
              // Customize redirect, if you don't want to use the standard /module.php/authoauth2/linkback.php
              'redirectUri' => 'https://myapp.example.com/callback',
              // See League\OAuth2\Client\Provider\GenericProvider for more options
              
              // Guzzle HTTP config
              // Wait up to 3.4 seconds for Oauth2 servers to respond
              //http://docs.guzzlephp.org/en/stable/request-options.html#timeout 
              'timeout' => 3.4,
              // http://docs.guzzlephp.org/en/stable/request-options.html#proxy
              'proxy' => [
              ],
              
              // All attribute keys will have this prefix
              'attributePrefix' => 'someprefix.'
              // Enable logging of request/response. This *will* leak you client secret and tokens into the logs
              'logHttpTraffic' => true, //default is false
              'logMessageFormat' => 'A Guzzle MessageFormatter format string', // default setting is sufficient for most debugging
              'logIdTokenJson' => true, //default false. Log the json in the ID token.
              
          ),

OpenID Connect Usage

For providers that support OpenID Connect discovery protocol the configuration can be simplified a bit. Only the issuer url, client id and client secret are required..

       'openidconnect' => array(
              'authoauth2:OpenIDConnect',
              // *** Required for all integrations ***
              'issuer' => 'https://www.example.com', # e.g https://accounts.google.com
              'clientId' => '133972730583345',
              'clientSecret' => '36aefb235314bad5df075363b79cbbcd',

              // Most Optional settings for OAuth2 above can be used
              // *** New Optional ***
              // Customize post logout redirect, if you don't want to use the standard /module.php/authoauth2/loggedout.php
              'postLogoutRedirectUri' => 'https://myapp.example.com/loggedout'
          ),

If your OP supports front channel single logout, you can configure https://hostname/SSP_PATH/module.php/authoauth2/logout.php?authSource=AUTHSOURCE where AUTHSOURCE is the id of your authsource in the authsources configuration (openidconnect in the example above)

Provider Specific Usage

There are numerous Offical and Third-Party providers that you can use instead of the generic OAuth2 provider. Using one of those providers can simplify the configurations.

To use a provider you must first install it composer require league/oauth2-some-provider and then configure it.

    'providerExample' => array(
        // Must install correct provider with: composer require league/oauth2-example
        'authoauth2:OAuth2',
        'providerClass' => 'League\OAuth2\Client\Provider\SomeProvider',
        'clientId' => 'my_id',
        'clientSecret' => 'my_secret',
    ),

Template Specific Usage

For some OAuth2 providers the generic endpoint configurations are already defined in ConfigTemplate. You can reference this to reduce the amount of typing needed in your authsource

    'google' => array_merge(\SimpleSAML\Module\authoauth2\ConfigTemplate::GoogleOIDC, [
        'clientId' => '3473456456-qqh0n4b5rrt7vkapgk3e4osre40.apps.googleusercontent.com',
        'clientSecret' => 'shhh',
        'urlAuthorizeOptions' => [
            'hd' => 'example.com',
        ],
    ]),

or by using the template option

    'providerExample' => array(
        'authoauth2:OAuth2',
        'template' => 'GoogleOIDC',
        'clientId' => 'my_id',
        'clientSecret' => 'my_secret',
    ),

Samples

Several of these samples show how to configure the generic endpoint to authenticate against Facebook, Amazon and Google, etc. In a lot of cases you can use a template from ConfigTemplate to make the configuration cleaner or you can use a provider specific implementations of the base OAuth2 client.

Generic Facebook

You can use the Facebook template 'template' => 'Facebook', and then provide just the clientId and clientSecret to have a cleaner looking config

    'genericFacebookTest' => array(
        'authoauth2:OAuth2',
        // *** Facebook endpoints ***
        'urlAuthorize' => 'https://www.facebook.com/dialog/oauth',
        'urlAccessToken' => 'https://graph.facebook.com/oauth/access_token',
        // Add requested attributes as fields
        'urlResourceOwnerDetails' => 'https://graph.facebook.com/me?fields=id,name,first_name,last_name,email',
        // *** My application ***
        'clientId' => '13397273example',
        'clientSecret' => '36aefb235314baexample',
        'scopes' => 'email',
        // *** Optional ***
        // Custom query parameters to add to authorize request
        'urlAuthorizeOptions' => [
            // Force use to reauthenticate
            'auth_type' => 'reauthenticate',
        ],
    ),

Generic Amazon

    'genericAmazonTest' => array(
        'authoauth2:OAuth2',
        // *** Amazon Endpoints ***
        'urlAuthorize' => 'https://www.amazon.com/ap/oa',
        'urlAccessToken' => 'https://api.amazon.com/auth/o2/token',
        'urlResourceOwnerDetails' => 'https://api.amazon.com/user/profile',
        // *** My application ***
        'clientId' => 'amzn1.application-oa2-client.94d04152358dexample',
        'clientSecret' => '8681bdd290df87example',
        'scopes' => 'profile',
    ),

Generic Google

View full Google instructions.

'genericGoogleTest' => array(
        'authoauth2:OAuth2',
        // *** Google Endpoints ***
        'urlAuthorize' => 'https://accounts.google.com/o/oauth2/auth',
        'urlAccessToken' => 'https://accounts.google.com/o/oauth2/token',
        'urlResourceOwnerDetails' => 'https://www.googleapis.com/oauth2/v3/userinfo',
        // *** My application ***
        'clientId' => '685947170891-exmaple.apps.googleusercontent.com',
        'clientSecret' => 'wV0FdFs_example',
        'scopes' =>  array(
            'openid',
            'email',
            'profile'
        ),
        'scopeSeparator' => ' ',
    ),

Provider Specific Google

View full Google instructions.

   'googleProvider' => array(
       // Must install correct provider with: composer require league/oauth2-google
       'authoauth2:OAuth2',
       'providerClass' => 'League\OAuth2\Client\Provider\Google',
       'clientId' => 'client_id',
       'clientSecret' => 'secret',
   ),

Debugging

HTTP Logging

You can enable http logging with the logHttpTraffic flag and optionally customize the format with logMessageFormat. See Guzzle's MessageFormatter class for how to define a format string.

security note: enabling http logging will make your client secret and any returned access or id tokens to appear in your logs.

Using Curl

You can use curl on the command line to interact with the OAuth2/OIDC server.

Get Code

The first step is get a valid code AND ensure the module doesn't try to use it. This can be done by constructing an authorize url with an invalid state value but with all other params correct

https://as.example.com/openid/authorize?state=invalid-state&scope=openid&response_type=code&redirect_uri=https%3A%2F%2Fmyapp.example.com%2Fsimplesaml%2Fmodule.php%2Fauthoauth2%2Flinkback.php&client_id=my_client

If you log in with the above it will redirect you back to your SSP instance with an authorization_code (which you should capture) and then your SSP instance will report an error about an invalid state parameter. The state check happens prior to consuming the authorization_code so you know SSP hasn't used it.

Get Access Token

Now you can use the code and try to get an access token

curl -d "code=REPLACE" \
    -d "client_secret=my_secret" \
    -d "client_id=my_client" \
    -d "redirect_uri=https://myapp.example.com/simplesaml/module.php/authoauth2/linkback.php" \
    -d 'grant_type=authorization_code' \
   https://as.example.com/openid/token

Get User Info

Take the access token from above and call the user info endpoint

curl -H "Authorization: Bearer $ACCESS_TOKEN" https://as.example.com/userInfo

Migrating from an existing auth module

If you are migrating away from an existing auth module, such as authfacebook you will need to one of the following:

  • add this module's authoauth2 redirect URI to the facebook app, or
  • override the authoauth2 authsource's redirect URI to match the authfacebook uri (https://myserver.com/module.php/authfacebook/linkback.php) AND do one of the following
    • edit /modules/authfacebook/www/linkback.php to conditionally call OAuth2ResponseHandler (see below)
    • configure an Apache rewrite rule to change '/module.php/authfacebook/linkback.php' to '/module.php/authoauth2/linkback.php'
    • symlink or edit /modules/authfacebook/www/linkback.php to invoke the /modules/authoauth2/www/linkback.php

Some social providers support multiple login protocols and older SSP modules may use the non-OAuth2 version for login. To migrate to this module you may need to make some application changes. For example

  • the LinkedIn module uses oauth1 and you may need to make adjustments to your app to move to their oauth2 API
  • moving from OpenID 2 Yahoo logins to OIDC Yahoo logins requires creating a Yahoo app.

Calling OAuth2ResponseHandler

To migrate from an existing module you can adjust that modules linkback/redirect handler to conditionally use the OAuth2ResponseHandler In the below example the code will use the authoauth2 if that is what initiated the process else use the existing handler

$handler = new \SimpleSAML\Module\authoauth2\OAuth2ResponseHandler();
if ($handler->canHandleResponse()) {
   $handler->handleResponse();
   return;
 } 

Development

To perform some integration tests you can run the embedded webserver. You may need to run composer install and then phpunit one time first to correctly link the project into SSP's modules directory

export SIMPLESAMLPHP_CONFIG_DIR=$PWD/tests/config/
mkdir -p /tmp/ssp-log/
php -S 0.0.0.0:8732 -t $PWD/vendor/simplesamlphp/simplesamlphp/www &

Then visit http://abc.tutorial.stack-dev.cirrusidentity.com:8732/

Note: *.tutorial.stack-dev.cirrusidentity.com resolves to your local host.

authsources.php contains some preconfigured clients. The generic facebook and google ones should work as is. The generic amazon one requires https. You can run use it and when Amazon redirects back to https change the url to http to proceed. The google provider authsource requires you to install the google auth module first.

Code style

Run phpcs to check code style

./vendor/bin/phpcs --standard=PSR2 lib/