cirrusidentity/simplesamlphp-module-cirrusgeneral

SSP Module of various filters developed by Cirrus Identity

v3.0.0-alpha.2 2023-10-26 23:35 UTC

Requires

• php: >=7.4
• simplesamlphp/composer-module-installer: ^1.1
• simplesamlphp/simplesamlphp: ^2.0

Requires (Dev)

• ext-tidy: *
• cirrusidentity/simplesamlphp-test-utils: v2.x-dev
• phpunit/phpunit: ^9.5
• simplesamlphp/simplesamlphp-test-framework: ^1
• squizlabs/php_codesniffer: *
• vimeo/psalm: ^5.8

LGPL-2.1-only

• simplesamlphp

README

Table of Contents generated with DocToc

• Installation
• ModifyingMetadataSource
  • Strategies
    • AdfsMetadataStrategy
    • OverridingMetadataStrategy
    • PhpMetadtaStrategy
• AttributeSplitter
• AttributeValueMapper
  • CSV file format
• PromptAttributeRelease
• ConditionalSetAuthnContext
• AttributeRemove
• ObjectSidConverter
• Conditional AuthProc Insertion
  • PhpConditionalAuthProcInserter
• Development
• Exploring with Docker
  • Things to try
    • Attribute prompt/picker

Installation

For SSP 2, use version 3 of the module

composer require cirrusidentity/simplesamlphp-module-cirrusgeneral:v3.0.0-alpha.1

For SSP 1.X use version 2 of the module

ModifyingMetadataSource

There is often a need to adjust the metadata for an entityId to fix certain values, or to add SSP specific config items. This is difficult to achieve if metadata is loaded from a remote source. The ModifyingMetadataSource allows you to configure different strategies to change the metadata that is loaded. The source delegates to other sources (like mdq or the serialize source) and then edits the metadata before returning it.

 'metadata.sources' => [
            [
                'type' => 'SimpleSAML\Module\cirrusgeneral\Metadata\Sources\ModifyingMetadataSource',
                // Any sources that you want to delegate to
                'sources' => [
                    array('type' => 'flatfile', 'directory' => __DIR__ . '/testMetadata'),
                    array('type' => 'flatfile', 'directory' => __DIR__ . '/testMetadata2'),
                ],
                'strategies' => [
                    ['type' => 'SimpleSAML\Module\cirrusgeneral\Metadata\AdfsMetadataStrategy'],
                    [
                        'type' => 'SimpleSAML\Module\cirrusgeneral\Metadata\OverridingMetadataStrategy',
                        'source' => array('type' => 'flatfile', 'directory' => __DIR__ . '/overrideMetadata'),
                    ],
                    [
                        'type' => 'SimpleSAML\Module\cirrusgeneral\Metadata\PhpMetadataStrategy',
                        // Run php code to edit the metadat. Defined variables are $metadata, $set, and $entityId
                        'code' => '
                             if ($set === "saml20-sp-remote") {
                                $metadata["attributes"] = $metadata["attributes"] ?? ["attr1", "attr2"];
                             } 
                        '
                    ]                    
                    // some other strategy
                    // ['type' => 'Myclass', 'configOption1' => true],
                ],
            ],
            // Any sources that you don't want to pass to the modifying strategis
            // [ 'type' => 'flatfile' ],
        ]

Strategies

AdfsMetadataStrategy

Add disable_scoping to any metadata that looks like ADFS

OverridingMetadataStrategy

Load additonal metadata from a source and combine it with the main metadata using +. A flatfile override strategy for saml20-sp-remote would look in the file saml20-sp-remote-override.php and then return the metadata as $overrideMetadata + $unalteredMetadata which will keep keys from the override metadata if the same key exists in the regular metadata.

PhpMetadtaStrategy

This strategy allows you to run php code snippets to adjust metadata. Your code will have 3 variables available: array $metadata, string $set, and string $entityId. $metadata will contain the current metadata for the entity and your code can make changes to this array.

If you have complex code logic you are better off creating your own strategy with unit tests.

AttributeSplitter

This AuthProc filter will split an attributes values on a delimiter and turn it into an array. Some systems stores the multi valued attributes, such as eduPersonAffiliation, as a comma delimited list - student,member This filter will split that into multiple values

Usage:

// In your authProc config
    20 => [
        'class' => 'cirrusgeneral:AttributeSplitter',
        'delimiter' =>  ',',  // Optional. Default is comma
        'attributes' => ['eduPersonAffiliation', 'urn:oid:1.3.6.1.4.1.5923.1.1.1.1'],
    ]

AttributeValueMapper

Maps a source attribute name and value to a new attribute name and values(s) based on csv file or or in php config. Useful when a datasource (for groups, entitlements, etc) contains names and values that need to be mapped to something new.

// In your authProc config
    20 => [
        'class' => 'cirrusgeneral:AttributeValueMapper',
        'csvFile' =>  '/patch/to/csv',
         'mappingLookup' => [
                // source attribute name
                'inc-eduPersonEntitlement' => [
                     // source value
                     'inc-eduPersonEntitlement-everfi' => [
                           // dest attribute      =>   [ dest val1, dest val2]
                           'eduPersonEntitlement' => ['val1', 'val2'],
                           'localEntitlement' => ['anotherValue'],
                     ]
                ],
         ]
    ]

CSV file format

Each line contains a source attribute and value, and if a user has an attribute of that value then they get the resulting destinationAttribute populated with the destinationValue. Duplicates are removed

sourceAttribute,sourceValue,destinationAttribute,destinationValue
group-test,newStudent,eduPersonAffiliation,student
group-med,newStudent,eduPersonAffiliation,student
group-test,newStudent,eduPersonAffiliation,member
group-test,oldStudent,eduPersonAffiliation,alumni
group-test,incoming-Student,eduPersonAffiliation,student
group-test,incoming-Student,entitlement,https://example.com/checkfinacialAid
group-test,newStudent,entitlement,urn:blah:blahstudent-app
group-med,med-student,eduPersonAffiliation,student
group-med,med-student,eduPersonAffiliation,other
group-med,newStudent,entitlement,urn:med:student-app
group-med,faculty,entitlement,urn:med:faculty-app

PromptAttributeRelease

If a user has a multi-valued attribute and the SP can only use/expects one value, then the PromptAttributeRelease filter can prompt the user to pick which value should be released to the SP. An example, an SP has different functionality depending on the eduPersonAffiliation value. This filter would allow user to select which of their affiliations to release.

// In your authProc config
    20 => [
        'class' => 'cirrusgeneral:PromptAttributeRelease',
         'attribute' => 'eduPersonAffiliation',
         // optional labels to prefix in front of values
         'labels' => [
             'student' => 'Student Role',
             'member'  => 'Generic Role'
             // any other values don't get a label and are shown as the plain value in the UI
         ]
         // optional: should the attribute value be shown after the label? defaults to true
         'displayAttributeValue' => false

ConditionalSetAuthnContext

This AuthProc filter allows you to assert a specific authnContextClassRef if value in the users state equals some expected value. For example some upstream systems may indicate the user was required to perform MFA by setting an attribute on the user. This filter will allow you to assert https://refeds.org/profile/mfa if that attribute is present.

Usage:

// In your authProc config of your IdP
    20 => [
        'class' => 'cirrusgeneral:ConditionalSetAuthnContext',
        'path' => ['Attributes', 'mfaActivated'], // The path of keys to traverse in the request state,
        'value' =>  'true',  // Using the string 'true' rather than a boolean true
        'contextToAssert' => 'https://refeds.org/profile/mfa',
        'ignoreForEntities' => ['match1', 'match2', 'other']

        // Optional context to assert if there is no match
        // 'elseContextToAssert' => 'https://refeds.org/profile/sfa'
    ]

// Example for Okta
      25 => array(
                    'class' => 'cirrusgeneral:ConditionalSetAuthnContext',
                    'path' => ['Attributes', 'session.amr'],
                    'value' => 'mfa',
                    'contextToAssert' => 'https://refeds.org/profile/mfa',
                ),

// Exmample for Aure AD
      49 => array(
                    'class' => 'cirrusgeneral:ConditionalSetAuthnContext',
                    'path' => ['Attributes', 'http://schemas.microsoft.com/claims/authnmethodsreferences'],
                    'value' => 'http://schemas.microsoft.com/claims/multipleauthn',
                    'contextToAssert' => 'https://refeds.org/profile/mfa',
                ),

AttributeRemove

This AuthProc filter allows you to define attributes that should always be removed. We use it with AzureAD since it always returns certain extra attributes (such as tenantId )that we want removed from the users attributes.

Usage:

// In your authProc config
    20 => [
        'class' => 'cirrusgeneral:AttributeRemove',
        'attributes' => ['http://schemas.microsoft.com/identity/claims/tenantid', 'http://schemas.microsoft.com/identity/claims/objectidentifier'],
        'attributeRegexes' => ['/^operational/']
    ]

ObjectSidConverter

ActiveDirectory's objectSid can be a in a binary format or as a formatted string. Sometimes you'll receive one and expect the other.

Conditional AuthProc Insertion

There are use cases where you want to run a set of authproc filters, but only if a certain condition is met when a user is logging in. Not all authproc filters support conditional use. Subclasses of BaseConditionalAuthProcInserter allow you to insert an arbitrary number of authproc filters at the BaseConditionalAuthProcInserter priority during authproc processing. This allows you to check things in the user's state prior to creating the filters.

PhpConditionalAuthProcInserter

PhpConditionalAuthProcInserter is an example of defining a boolean expression that determines if the authproc filters are created. Two variables are available: array $attributes and array $state

// In your authsources.php or saml20-idp-metadata.php or whereever you define your authprocs
   'authproc' => [
       10 => [
           // a norma authproc
           'core:AttributeMap'
       ],
       20 => [
             'class' => 'cirrusgeneral:PhpConditionalAuthProcInserter',
             //php boolean expression. Two variables are available: $attributes and $state
            'condition' => 'return $state["saml:sp:State"]["saml:sp:AuthnContext"] === "https://refeds.org/profile/mfa";',
             // These will only get created if AuthnContext is refeds MFA, and they will run immediately after
             // PhpConditionalAuthProcInserter
             'authproc' => [
                [
                  'class' => 'core:AttributeAdd',
                  'newAttribute' => array('newValue'),
                ],
                [
                   'class' => 'core:AttributeMap',
                ],
             ],
             // These will only get created if authnContext is not refeds MFA
             'elseAuthproc' => [
                [
                  'class' => 'somemodule:PerformMfa',
                ],
                [
                   'class' => 'somemodule:SetRefedsMfa',
                ],
             ]
       ],
       30 => [
          // another normal authproc
          'core:AttributeMap'
       ]


   ]

Development

Run phpcs to check code style

./vendor/bin/phpcs

Run phpunit to test

./vendor/bin/phpunit

You can auto correct some findings from phpcs. It is recommended you do this after stage your changes (or maybe even commit) since there is a non-trivial chance it will just mess up your code.

./vendor/bin/phpcbf

Run psalm to find issues

./vendor/bin/psalm   --no-cache

Exploring with Docker

You can explore these features with Docker.

docker run -d --name ssp-cirrusgeneral \
   --mount type=bind,source="$(pwd)",target=/var/simplesamlphp/staging-modules/cirrusgeneral,readonly \
  -e STAGINGCOMPOSERREPOS=cirrusgeneral \
  -e COMPOSER_REQUIRE="cirrusidentity/simplesamlphp-module-cirrusgeneral:@dev" \
  -e SSP_ENABLED_MODULES="cirrusgeneral" \
  --mount type=bind,source="$(pwd)/tests/docker/metadata/",target=/var/simplesamlphp/metadata/,readonly \
  --mount type=bind,source="$(pwd)/tests/docker/authsources.php",target=/var/simplesamlphp/config/authsources.php,readonly \
  --mount type=bind,source="$(pwd)/tests/docker/config-override.php",target=/var/simplesamlphp/config/config-override.php,readonly \
  --mount type=bind,source="$(pwd)/tests/docker/cert/",target=/var/simplesamlphp/cert/,readonly \
   -p 443:443 cirrusid/simplesamlphp:v2.0.0

Then log in as admin:secret to https://cirrusgeneral.local.stack-dev.cirrusidentity.com/simplesaml/module.php/core/frontpage_welcome.php to confirm things work.

Things to try

Attribute prompt/picker

The Idp has the PromptAttributeRelease authproc filter enabled for the eduPersonAffiliation attribute. If a user has more than one value they will need to pick which value to release. See authsources.php for the available users. To make the IdP run it's authproc filters you need to send a login from an SP, and the sp-auth source will do that login.