intervieweb/spid-php-lib

PHP package for SPID authentication

v1.0.4 2024-04-22 14:58 UTC

README

Main differences with official release:

  • implements logging
  • uses PSR-12 style guide

spid-php-lib

PHP package for SPID authentication.

This PHP package is aimed at implementing SPID Service Providers. SPID is the Italian digital identity system, which enables citizens to access all public services with a single set of credentials. This package provides a layer of abstraction over the SAML protocol by exposing just the subset required in order to implement SPID authentication in a web application.

Alternatives for PHP:

Framework specific libraries and examples based on spid-php-lib:

Alternatives for other languages:

Table of Contents

Repository layout

  • bin/ auxiliary scripts
  • example/ contains a demo application
  • src/ contains the library implementation
  • test/ contains the unit tests

Getting Started

Tested on: amd64 Debian 9.5 (stretch, current stable) with PHP 7.0.

Supports PHP 7.0, 7.1 and 7.2.

Prerequisites

sudo apt install composer make openssl php-curl php-zip php-xml

Configuring and Installing

NOTE: during testing, please use the test Identity Provider spid-testenv2.

  1. Install with composer

    composer require italia/spid-php-lib

  2. (OPTIONAL) Manually generate key and certificate files for your Service Provider (SP).

    Example: openssl req -x509 -nodes -sha256 -days 365 -newkey rsa:2048 -subj "/C=IT/ST=Italy/L=Milan/O=myservice/CN=localhost" -keyout sp.key -out sp.crt

    This step can be skipped: the library takes care of this step automatically if you declare the optional sp_key_cert_values key in the settings array. Check the example in the Usage section for further details.

  3. Download the Identity Provider (IdP) metadata files and place them in a directory in your project, for example idp_metadata. A convenience tool is provided to download those of the production IdPs: vendor/italia/spid-php-lib/bin/download_idp_metadata.php, example usage:

    mkdir idp_metadata
    php vendor/italia/spid-php-lib/bin/download_idp_metadata.php ./idp_metadata

    TEST ENVIRONMENT: If you are using spid-testenv2, manually download the IdP metadata and place it in your idp_metadata folder

  4. Make your SP known to IdPs: for production follow the guidelines at https://www.spid.gov.it/come-diventare-fornitore-di-servizi-pubblici-e-privati-con-spid

    TEST ENVIRONMENT: simply download your Service Provider (SP) metadata and place it in the appropriate folder of the test environment. The test environment must be restarted after every change to the SP metadata.

Usage

All classes provided by this package reside in the Italia\Spid namespace. More detailed documentation is available in the SAMLInterface.php file.

Load them using the composer-generated autoloader:

require_once(__DIR__ . "/vendor/autoload.php");

The main class is Italia\Spid\Sp (service provider).

Generate a settings array following this guideline

$settings = array(
    'sp_entityid' => SP_BASE_URL, // preferred: https protocol, no trailing slash, example: https://sp.example.com/
    'sp_key_file' => '/path/to/sp.key',
    'sp_cert_file' => '/path/to/sp.crt',
    'sp_comparison' => 'exact', // one of: "exact", "minimum", "better" or "maximum"
    'sp_assertionconsumerservice' => [
        // order is important ! the 0-base index in this array will be used as ID in the calls
        SP_BASE_URL . '/acs',
        ...
    ],
    'sp_singlelogoutservice' => [
        // order is important ! the 0-base index in this array will be used as ID in the calls
        [SP_BASE_URL . '/slo', 'POST'],
        [SP_BASE_URL . '/slo', 'REDIRECT']
        ...
    ],
    'sp_org_name' => 'your organization full name',
    'sp_org_display_name' => 'your organization display name',
    'sp_key_cert_values' => [ // Optional: remove this if you want to generate .key & .crt files manually
        'countryName' => 'Your Country',
        'stateOrProvinceName' => 'Your Province or State',
        'localityName' => 'Locality',
        'commonName' => 'Name',
        'emailAddress' => 'your@email.com',
    ]
    'idp_metadata_folder' => '/path/to/idp_metadata/',
    'sp_attributeconsumingservice' => [
        // order is important ! the 0-base index in this array will be used as ID in the calls
        ["fiscalNumber"],
        ["name", "familyName", "fiscalNumber", "email", "spidCode"],
        ...
    ],
    // Time in seconds of skew that is acceptable between client and server when checking OnBefore and NotOnOrAfter
    // assertion condition validity timestamps, and IssueInstant response / assertion timestamps. Optional.
    // Default is 0. Acceptable range: 0-300 (inclusive)
    'accepted_clock_skew_seconds' => 100
);

then initialize the main Sp class

$sp = new Italia\Spid\Sp($settings);

Don't want the library to generate .key and .crt files for you? Then remove the sp_key_cert_values key from the settings array, or decalre

// $autoconfiguration skips .key/.crt generation if set to false
$sp = new Italia\Spid\Sp($settings, null, $autoconfiguration = false);

Performing login

// shortname of IdP, same as the name of corresponding IdP metadata file, without .xml
$idpName = 'testenv';
// index of assertion consumer service as per the SP metadata (sp_assertionconsumerservice in settings array)
$assertId = 0;
// index of attribute consuming service as per the SP metadata (sp_attributeconsumingservice in settings array)
$attrId = 1;

// Generate the login URL and redirect to the IdP login page
$sp->login($idpName, $assertId, $attrId);

Complete the login operation by calling

$sp->isAuthenticated();

at the assertion consumer service URL.

Then call

$userAttributes = $sp->getAttributes();

to receive an array of the requested user attributes.

Performing logout

Call

// index of single logout service as per the SP metadata (sp_singlelogoutservice in settings array)
$sloId = 0;

$sp->logout($sloId);

The method will redirect to the IdP Single Logout page, or return false if you are not logged in.

Complete API

Example

A basic demo application is provided in the example/ directory of this repository.

/example and /tests folders are NOT provided with the production version from packagist, remember to require the dev-develop version or just clone this repository (advised)

To try it out:

  1. Generate a test certificate and key pair with:

    openssl req -x509 -nodes -sha256 -days 365 -newkey rsa:2048 -subj "/C=IT/ST=Italy/L=Milan/O=myservice/CN=localhost" -keyout sp.key -out sp.crt
  2. Adapt the hostname of the SP changing the $base variable in the example/index.php file; the browser you'll be testing from must be able to resolve the FQDN (the default is https://sp.example.com). Using HTTPS is strongly suggested.

  3. Configure and install the test IdP spid-testenv2

  4. Serve the example dir from your preferred webserver

  5. Visit https://sp.example.com/metadata to get the SP metadata, then copy these over to the IdP and register the SP with the IdP

  6. Visit https://idp.example.com/metadata to get the IdP metadata, then save it as example/idp_metadata/testenv.xml to register the IdP with the SP

  7. Visit: https://sp.example.com and click login.

Demo application

A Docker-based demo application is available at https://github.com/simevo/spid-php-lib-example.

Features

  • provides a lean implementation without relying on external SAML packages
  • routing-agnostic, can be integrated in any web framework / CMS
  • uses a session to store the authentication result and the received attributes
  • does not currently support Attribute Authority (AA)

More features

  • Generation of SPID button markup

Troubleshooting

It is advised to install a browser plugin to trace SAML messages:

In addition, you can use the SAML Developer Tools provided by onelogin to understand what is going on

Testing

To test and lint this package you must place yourself in its root directory, then follow the provided instructions.

Assuming you followed the installation instructions with composer, simply do:

cd vendor/italia/spid-php-lib

Unit tests

Install prerequisites with composer, generate key and certificate for the SP and download the metadata for all current production IdPs with:

composer install
bin/download_idp_metadata.php example/idp_metadata

then launch the unit tests with PHPunit:

./vendor/bin/phpunit --stderr --testdox tests

Linting

This project complies with the PSR-2: Coding Style Guide.

Make sure you are in the package directory, then lint the code with:

./vendor/bin/phpcs --standard=PSR2 xxx.php

Contributing

For your contributions please use the git-flow workflow.

See also

Authors

Lorenzo Cattaneo and Paolo Greppi, simevo s.r.l.

License

Copyright (c) 2018-2020, Developers Italia

License: BSD 3-Clause, see LICENSE file.