Copyright 2011 SWITCH - Serving Swiss Universities. See LICENSE file for details. ------------------------------------------------------------------------------- SWITCH WAYF Contact: aai@switch.ch or go to http://www.switch.ch/aai/wayf Version: See head of file 'WAYF' in the same directory Project web site: https://forge.switch.ch/redmine/projects/wayf Bug reports/feature requests: https://forge.switch.ch/redmine/projects/wayf/issues ------------------------------------------------------------------------------- Description: The SWITCHwayf is an implementation of the Shibboleth WAYF and SAML2 Discovery Service protocol for use withing a Shibboleth architecture. ------------------------------------------------------------------------------- Security Notes Release (25. October 2010): The Discovery Service protocol as defined in http://docs.oasis-open.org/security/saml/Post2.0/sstc-saml-idp-discovery.pdf states that the protocol creates opportunities for phishing attacks as do all SSO protocols that make use of redirection. The specification states that an implementation "SHOULD" examine the 'return' parameter used in a Discovery Service request and match it against the extension in SAML metadata. The implementation of the Discovery Service protocol in the SWITCHwayf prior to version 1.14 does NOT verify the return parameter even if SAML metadata was used to generate the list of Identity Provider. Version 1.14 or newer fixes this problem. Thanks to Tom Scavo for making us aware of this issue. ------------------------------------------------------------------------------- Some of the Features: - Preselecting entry in drop down list by - SAML common domain cookie that contains selected Identity Providers - resource path info hint (e.g. /WAYF/unige.ch?shire=https://... selects University of Geneva, depends of course on the ID scheme a federation uses) - Kerberos preselection - IP range preselection - IP reverse DNS lookup preselection - Transparent redirection mode, e.g. /WAYF/unige.ch/redirect?shire=https://... - Can read SAML2 metadata files - Supports Discovery Service and the Shibboleth authentication request protocol - Various customizations options for header, footer, language strings etc. - HTML code generation for embedding the WAYF directly into a web page - Support for templates - Support for remembering IdP selection permanently - I18N support, currently language packs for en, de, it, fr and pt are included ------------------------------------------------------------------------------- Requirements: - The web server must support PHP5 - If the configuration and the backup configuration differ, you have to make sure the user that runs the php script has write access for the configuration files. - PHP XML Parser extension for parsing SAML2 metadata ------------------------------------------------------------------------------- Installation: 1. Unpack the Zip archive into a directory on a host where Apache (IIS also should work) is deployed. 2. Make a copy of the *.dist.php files - Copy the file config.dist.php and name it config.php This is the main configuration file of the SWITCHwayf - Copy the file IDProvider.conf.dist.php and name it IDProvider.conf.php This file contains the list of Identity Providers that you configure by hand 3. Make sure that permissions for the files: - SProvider.metadata.php - IDProvider.metadata.php - metadata.lock - $WAYFLogFile (typically /var/log/apache2/wayf.log) are set such that the web server user (e.g. www-data, www or httpd) has write permissions for these two files. 4. Adapt the SWITCHwayf configuration in config.php. There are comments in that file that should help you make suitable choices for your use case. 5. If you use Apache 2, add the following statement to the Apache configugration: -- SetHandler php5-script -- In some clustered environments with FastCGI it may be necessary to use something like -- Options +FollowSymLinks RewriteEngine On RewriteRule ^WAYF/(.*)$ WAYF.php/$1 [QSA,L] RewriteRule ^WAYF$ WAYF.php [QSA,L] -- Alternatively, one also could rename the file 'WAYF' to 'WAYF.php'. 6. When using the embedded WAYF feature it might be necessary to add a line to the Apache configuration like below in order to prevent certain web browsers from not displaying the Embedded WAYF or parts of it: -- Header set P3P "CP=\"NOI CUR DEVa OUR IND COM NAV PRE\"" -- For that to work, the Apache header extension must also be enabled with a command like: -- a2enmod headers /etc/init.d/apache2 reload -- See http://www.w3.org/P3P/ for more details on P3P. 7. Test access by calling the WAYF with a URL like: https://your.host.com/path/to/WAYF Use this URL as Location for your Shibboleth configuration. The WAYF will automatically be able to detect whether it receives a Shibboleth authentication request or a Discovery Service request. ------------------------------------------------------------------------------- General Update Instructions: 1. Make a backup of the directory where the currently active version of the SWITCHwayf is installed 2. Get the compressed archive of the new version and move it into the directory of the currently deployed version 3. Unpack the archive with zip or tar This step will overwrite some existing files. Files whose name starts with 'custom-' will not be overwritten. 4. Have a look at config.dist.php and compare this file with your current config.php in order to identify new configuration options. ------------------------------------------------------------------------------- Specific Update Instructions: Updates from versions before 1.15 The keys of the following languages strings were renamed and should be adapted in your custom languages.php file: - 'about_aai' was renamed to 'about_federation' - 'about_switch' was renamed to 'about_organisation' - 'switch_description' was renamed to 'additional_info' Update from versions before 1.4.3: The new setting '$metadataLockFile' was introduced in config.php. It allows configuring the location of the lock file. When the SWITCHwayf is used in a Windows environment, the path to this file probably has to be adapted. Update from versions before 1.8: This version has a slightly different structure than previous versions. Therefore, it is recommended to start with a clean installation. However, you should be able to take over most of your old config.php functions and use them in the new template.php file again to keep your customized look and feel. ------------------------------------------------------------------------------- Troubleshooting: Generall, if there is an error or an exception, the WAYF will log the to syslog. In case there is a problem and you see only a white page without any output, open config.php in a text editor, go to the bottom of the file and set: $developmentMode = true; This will output PHP warning messages which are otherwise supressed. ------------------------------------------------------------------------------- Customizations: Since version 1.12 any graphical aspects of this WAYF/DS implementation can be customized such that these changes survive an upgrade. Files whose names start with 'default-' can be copied and renamed to start with 'custom-' in order to customize the file's behaviour. In particular, the following customizations can be applied: HTML header: custom-header.php Customize page header HTML Footer: custom-footer.php Customize page footer HTML Body: custom-body.php Customize WAYF/DS body HTML Body: custom-settings.php Customize WAYF/DS permanent settings body HTML Body: custom-notice.php Customize WAYF/DS permanent settings notice body HTML Body: custom-embedded-wayf.php Customize WAYF/DS body HTML Error: custom-error.php Customize error messages CSS Styles: css/custom-styles.css Customize CSS styles that are printed inline in header. The custom styles are loaded in addition to the default styles. Therefore, they can be used to overwrite the default CSS styles. Languages: custom-languages.php Can be used to change default or add new language strings. The custom languages strings in addition to the default styles. Therefore, they can be used to overwrite the default CSS styles. If the above files don't exist, the default templates and settings will be used. To create a custom template, copy of the default files with cp default-{$template}.php custom-{$template}.php where {$template} stands for the file you want to customize. ------------------------------------------------------------------------------- Logging: The general log where errors are written to is syslog. This log file will contain error messages for example in case files cannot be read or written. If the configuration option $useLogging is true, a log file will be written to the path specified in $WAYFLogFile. This log file is an audit log file where each line is an entry of the form: #DATE# #TIME# #IP# #IDP_SELECTION# #REQUEST_TYPE# #IDP_ENTITYID# #FORWARDING_URL# Log entries are only created if the user was forwarded to an Identity Provider. #DATE# Date of request, e.g. 2010-11-02 #TIME# Time of request, e.g. 06:25:13 #IP# IP of requester, e.g. 127.0.0.1 #IDP_SELECTION# How the IdP was selected: Cookie or Request #REQUEST_TYPE# Type of request: DS, WAYF, Embedded-DS, Embedded-WAYF #IDP_ENTITYID# EntityID of the IdP the user was forwarded to. #FORWARDING_URL# URL the user was redirected to ------------------------------------------------------------------------------- Optimizations: If your instance of the SWITCHwayf has many requests and the load is becoming higher and higher, you might want to think about using a PHP opcode cacher like XCache, apc, eaccelerator, phpa, truck-mmcache or similar. Using such a tool can decrease the processing time of the PHP code almost by half. However, internal tests have shown that the bottleneck in general is not the PHP processing but the TLS handshake, which has nothing to do with PHP itself. Benchmark tests conducted by SWITCH demonstrated that generating the Javascript WAYF/embedded-wayf.js can be speed up by 100% if the script provided the script is accessed via HTTP (without TLS). However, if the script is accessed via HTTPS (default in SWITCHaai), the overall speed gain by using XCache is less than 1% because the TLS hand-shake is what consumes most CPU time. ------------------------------------------------------------------------------- SAML2 Metadata support: In case you want the WAYF/DS to display the list of IdPs by parsing them from a SAML2 Medatadata file that is used by Shibboleth - Set $useSAML2Metadata in config.php to true - Specify the path to the metadata file that shall be read in $metadataFile and make sure this file is updated regularely by Shibboleth or a cron job - Make sure the files specified in $metadataIDPFile and $metadataSPFile can be written by the userthat executes the PHP script (the web server user, e.g. www-data or _www) The parsend IDP and SP entries will be stored in $metadataIDPFile and $metadataSPFile as executable PHP code. Storing parsed information in JSON or PHP serialized format would allow faster reading and executing in general. However, for large numbers of entities an opcode cacher might speed up execution time considerably (see chapter "Optimization" above) thanks to this format. If you want to change, remove or extend an entry from this automatically generated file, you can extend the IDP definitions by modifying them in the $IDPConfigFile. In case you want to overwrite some IDP values with entries in the $IDPConfigFile, make sure the entry $SAML2MetaOverLocalConf is set to false; For example you could change the displayed name of an IdP by adding an entry in the file $IDPConfigFile like: $IDProviders["urn:mace:switch.ch:SWITCHaai:switch.ch"]["Name"] = "Foobar"; You could also manually force the IdP list being upgraded by running the readMetadata.php in command line mode, e.g. by executing a cron script like: 5 * * * * /usr/bin/php readMetadata.php > /dev/null This feature has been initially developed in the framework of GRNET's project VNOC by Pavlos Drandakis. ------------------------------------------------------------------------------- Embedded WAYF support: With the embedded WAYF support you as an administrator of an application that is protected by Shibboleth, can easily integrate a Discovery Service on the home page of your application just by copying and adapting the HTML code snippet at the bottom of this file. The embedded WAYF then will display on the remote site a drop-down list with the same Identity Providers as if you were on this instance of the WAYF directly. However, you can also configure the embedded WAYF for your site by hiding or adding certain Identity Providers (even from remote federations) or adapt the look and feel of the embedded wayf. This can be done by simpling modifying the JavaScript variables in the HTML snippet that can be found at the bottom of the page. Note: If you operate a WAYF for your federation, you must carefully protect the host this WAYF is operated on when you activate this feature. If your WAYF host gets compromised, an attacker could modify the JavaScript that is embedded on the remote site in a malicous wayf (e.g. phish the user's password, redirect users to malicous pages, steal their sessions etc). You also have to make sure that your central WAYF has a very high availability because a lot of third-party services will depend on it. Also, please be aware that using the Embedded WAYF allows anybody to guess a user's Home Organisation without much effort. This information then could be used for phising attacks for example! ------------------------------------------------------------------------------- Kerberos support: Your web server needs to support Negotiate/SPNEGO Kerberos protocol. For example by using mod_auth_kerb. - Make a symlink of the file 'WAYF' and name it like configured in the variable $kerberosRedirectURL - Protect file $kerberosRedirectURL with Kerberos. The Kerberos realm must be specified in "IDProvider.conf.php" for each IdP. Each IdP's KDC must also establish a Kerberos cross-realm trust with the WAYF's KDC. This was tested with a Windows 2000 KDC, with the WAYF running on RHEL4. Credits for this feature go to Josh Howlett from Bristol University. ------------------------------------------------------------------------------- Configuration file format: Checkout the file 'IDProvider.conf.php' for an example of the file format. It's supposed to be mostly self-explanatory. Basically the file format is PHP code that defines an array of arrays called $IDProviders. The keys of the array $IDProviders must correspond to the entityIDs of the Identity Providers or a unique value in case of a cascaded WAYF/DS or a category. The entityID must be a valid URI (URL or URN) where in the case of a URN the last component must be a valid hostname. If metadata is not parsed from SAML2 metadta (using the setting $useSAML2Metadata = false), the IdPs and category entries will be displayed in order as defined in the configuration file and no sorting is done. If metadata is used ($useSAML2Metadata = true) to generate the list of Identity Providers, the Identity Providers will first be sorted according to their type/category, their Index value (see below) and then alphabetically after their (local) Name within the same type category. If an IdP does not have a type, its category is 'unknown'. If there exists a type for an IdP that does not have a corresponding category it will be displayed in the category 'unknown' at the end of the drop down list but will keep its type value (this is important for the Embedded Discovery Service). A general entry for an Identity Provider, a cascaded WAYF/DS or a category is of the following form: $IDProviders[#key#] = #entry# #key# is a unique value that must correspond to the entity's entityID in case the entry stands for an Identity Provider. For entries of Type category, the #key# should be an identifier that corresponds to a 'Type' of an IdP. #entry# is another hash array with the following keys: ['Type']: Optional Type that is used for the embedded wayf to hide or show certain categories. Default type will be 'unknown' if not specified. An entry for another WAYF/DS that the user shall be redirected to should have ['Type'] ='wayf The Type values 'category' and 'wayf' are reserved words that are not allowed to be assigned to entries for Identity Providers. ['Name']: Mandatory Default name to display in drop-down list ['en'|'it'|'fr'|'de'|'pt']['Name']: Optional Display name in other languages ['SSO']: Mandatory Should be the SAML1 SSO endpoint of the IdP ['Realm']: Optional Kerberos Realm ['IP'][]: Optional IP ranges of that organizations that can be used to guess a user's Identity Provider ['Index']: Optional An alphanumerical value that is used for sorting categories and Identity Provider in ascending order if the Identity Providers are parsed from metadata. This is only relevant if $includeLocalConfEntries = true For category entries, only Type, (local) Name and Index are relevant. ------------------------------------------------------------------------------- Version History: 1.15 Release date: 18. October 2011 - A default and custom CSS file can now be used - Graphical design now is based new SWITCH harmos elements - Adapted JSON output to be compatible with the supported by Shibboleth - Renamed some string keys to make them independent from SWITCH. Please review the 'Specific Update Instructions' in this document - Focus on submit button works better with different browsers - Invalid values for width and height are now defaulted to auto for Embedded WAYF - Fixed a URL composing bug that resulted in a wrong return URL to the Service Provider if the return parameter did not contain any GET arguments. Reported by Tom Scavo - Made implementation behave according to the Discovery Service protocol specification when it comes to the return parameter. This parameter is optional in case the DS knows the SP Discovery URL. Reported by Tom Scavo. 1.14.3 Release date: 4. March 2011 - Fixed a race condition. Thanks go to Robert Basch from MIT for reporting the issue and providing a patch. 1.14.2 Release date: 15. December 2010 - IDProvider.conf.php and config.php are not overwritten anymore by upgrades - Logging to Syslog now works properly and is more consistent - Access log now properly locks file - Unknown category is not shown anymore when there is no other category - Namespaces are now taken properly into account when parsing SAML2 metadata. Thanks go to Olivier Salaün for reporting this issue and submitting a patch. - Improved installation instructions 1.14.1 Release date: 12. November 2010 - Fixed an encoding bug that affected non-ASCII characters in JavaScripts. Thanks to Prof. Kazutsuna Yamaji for reporting this issue. - Corrected behaviour of $enableDSReturnParamCheck and $useACURLsForReturnParamCheck. There won't be an error anymore if an SP has no extension defined. In such a case there will only be a check if $useACURLsForReturnParamCheck is enabled. - Fixed a bug in readMetadata.php that prevented CLI execution - Changed the default configuration option to generate the Embedded WAYF to false due to some concerns regarding phishing attacks - Added proper copyright statements to all source code files To see the revision history of older versions, please have a look at: https://forge.switch.ch/redmine/projects/wayf/wiki/Changes Releases with a version number X.Y.Z usually contain bug fix releases, typo corrections and graphical changes whereas releases with a version number X.Y usually introduce new functionality. ------------------------------------------------------------------------------- Embedded WAYF code snippet: To get a valid HTML snippet to embedd in a web page, please access your WAYF with a URL like: https://#HOSTNAME#/#PATH_TO_WAYF#/WAYF/embedded-wayf.js/snippet.html The script then should return some HTML code that can be embedded together with short descriptions of the available settings. Embedded WAYF code limitations: If the embedded WAYF is placed on the right side or at the bottom of a web page, it may be that the web browser cannot expand and render the complete drop-down list of Identity Providers. ------------------------------------------------------------------------------- Path Info parameters and files: Modifying the WAYF's URL it is possible to influence its behaviour. This can be done by appending certain Path Info extension to the URL. The Path Info components can also be combined. The allowed syntax is: [/#i18n string#][/redirect][/#entityID hostname#] [/#i18n string#][/embedded-wayf.js] [/embedded-wayf.js/snippet.html] [/IDProviders.json] [/IDProviders.php] [/IDProviders.txt] Note: Your web server must support the use of Path Info. Hinted Identity Provider and transparent redirects -------------------------------------------------- Path Info Extensions: [/redirect][/#entityID hostname#] #entityID hostname# must be the host name of an entityId or the last component of a URN. Examples: https://aai-login.switch.ch/idp/shibboleth -> aai-login.switch.ch urn:mace:switch.ch:aaitest:aai-demo-idp.switch.ch -> aai-demo-idp.switch.ch If the '/redirect' is included in the Path Info as well, the web browser is redirected transparently to the specified entityID hostname. Note: One must make sure that the entityID hostname is not the same as one of the reserved keywords like 'redirect', the below mentioned file types or a i18n langauge abbreviation. Language preselection: ---------------------- Path Info Extensions: [/#i18n string#] Examples of i18n strings are 'en', 'de_CH' or 'fr_CH.ISO8859-1' etc. However, in the default distribution only 'en', 'de', 'fr', 'it' and 'pt' are available and supported. But it would be easy to create sub types of existing languages for country/region support by adding something like this to languages.php: -- // Create a country specific copy of the German language strings $langStrings['de_CH'] = $langStrings['de']; // Overwrite a specific string $langStrings['de_CH']['title'] = 'Auswahl der Heimorganisation'; -- Special handlers: ----------------- In order for the Embedded WAYF feature to work there are some special files that need to be generated. The following Path Info Extensions must be the last components of the Path Info URL. Path Info Extensions: [/deleteSettings] As the name suggests, this handler deletes all settings cookies that were stored by the WAYF service in cookies. Unless there is a 'return' GET argument provided the user is sent to the settings page. [/embedded-wayf.js] Generates the JavaScript for the Embedded WAYF [/embedded-wayf.js/snippet.html] Generates HTML snippet for the Embedded WAYF [/idps-and-state.json] Returns JSON data structure that contains the content of the IDProviders array. The last element of that array will be a key called 'preselectedIDP', which contains the Identity Provider that would be preselected in the drop-down list for that user. [/IDProviders.txt] Same as above but in human readable form. [/IDProviders.php] Same as above but as PHP code ------------------------------------------------------------------------------- Credits: Find below the list of people who have contributed to code, either because they found bugs, suggested improvements or contributed code. Have a look at the version history in order to see the individual contributions. The list is sorted alphabetically. - Robert Basch from MIT (US) - Pavlos Drandakis from University of Athens (GR) - Nicolas Dunand from Université Lausanne (CH) - Michael R. Gettes from Internet2 (US) - Nuno Gonçalves from FCCN (PT) - Florent Guilleux from CRU (FR) - Josh Howlett from University of Bristol (UK) - Franz Kuster from ETHZ (CH) - Wolgang Lierz from ETH Zurich (CH) - Lourival Pereira Vieira Neto from RNP (BR) - Martins Purins from Latvijas Universitates (LV) - Olivier Salaün from RENATER (FR) - Tom Scavo from Internet2 (US) - Mika Suvanto from CSC (FI) - Huân Thebault from Centre de Calcul de l'IN2P3 (FR) - Prof. Kazutsuna Yamaji from NII (JP) - And of course all SWITCH staff members who have contributed suggestions, bug fixes and translation to this code.