SimpleSAML\Module\ldap\Auth\Source\Ldap

Complexity

Total Complexity

18

Size/Duplication

Total Lines	213
Duplicated Lines	0 %

Importance

Changes	7
Bugs	1	Features	0

4 Methods

Rating	Name	Duplication	Size	Complexity
A	__construct()	0	8	1
B	search()	0	49	7
A	bind()	0	12	3
B	login()	0	93	7

<?php

declare(strict_types=1);

namespace SimpleSAML\Module\ldap\Auth\Source;

use SimpleSAML\Assert\Assert;
use SimpleSAML\Configuration;
use SimpleSAML\Error;
use SimpleSAML\Logger;
use SimpleSAML\Module\core\Auth\UserPassBase;
use Symfony\Component\Ldap\Entry;
use Symfony\Component\Ldap\Exception\ConnectionException;
use Symfony\Component\Ldap\Ldap as LdapObject;
use Symfony\Component\Ldap\Adapter\ExtLdap\Query;

use function array_fill_keys;
use function array_keys;
use function array_map;
use function array_pop;
use function array_values;
use function count;
use function explode;
use function is_array;
use function sprintf;
use function strval;
use function str_replace;
use function var_export;

/**
 * LDAP authentication source.
 *
 * See the ldap-entry in config-templates/authsources.php for information about
 * configuration of this authentication source.
 *
 * @package simplesamlphp/simplesamlphp-module-ldap
 */

class Ldap extends UserPassBase
{
    /**
     * An LDAP configuration object.
     */
    private Configuration $ldapConfig;


    /**
     * Constructor for this authentication source.
     *
     * @param array $info  Information about this authentication source.
     * @param array $config  Configuration.
     */
    public function __construct(array $info, array $config)
    {
        // Call the parent constructor first, as required by the interface
        parent::__construct($info, $config);

        $this->ldapConfig = Configuration::loadFromArray(
            $config,
            'authsources[' . var_export($this->authId, true) . ']'
        );
    }


    /**
     * Attempt to log in using the given username and password.
     *
     * @param string $username  The username the user wrote.
     * @param string $password  The password the user wrote.
     * @return array  Associative array with the users attributes.
     */
    protected function login(string $username, string $password): array
    {
        $encryption = $this->ldapConfig->getString('encryption', 'ssl');
        Assert::oneOf($encryption, ['none', 'ssl', 'tls']);

        $version = $this->ldapConfig->getInteger('version', 3);
        Assert::positiveInteger($version);

        $ldapServers = [];
        foreach (explode(' ', $this->ldapConfig->getString('connection_string')) as $connection_string) {
            Assert::regex($connection_string, '#^ldap[s]?:\/\/#');

            $ldapServers[] = LdapObject::create(
                $this->ldapConfig->getString('extension', 'ext_ldap'),
                [
                    'connection_string' => $connection_string,
                    'encryption' => 'ssl',
                    'version' => $version,
                ]
            );
        }

        $searchScope = $this->ldapConfig->getString('search.scope', Query::SCOPE_SUB);
        Assert::oneOf($searchScope, [Query::SCOPE_BASE, Query::SCOPE_ONE, Query::SCOPE_SUB]);

        $referrals = $this->ldapConfig->getValue('referrals', Query::DEREF_NEVER);
        Assert::oneOf($referrals, [Query::DEREF_ALWAYS, Query::DEREF_NEVER, Query::DEREF_FINDING, Query::DEREF_SEARCHING]);

        $timeout = $this->ldapConfig->getString('timeout', 3);
        $searchBase = $this->ldapConfig->getArray('search.base');
        $options = [
            'scope' => $searchScope,
            'timeout' => $timeout,
            'deref' => $referrals,
        ];

        $searchEnable = $this->ldapConfig->getBoolean('search.enable', false);
        if ($searchEnable === false) {
            $dnPattern = $this->ldapConfig->getString('dnpattern');
            $dn = str_replace('%username%', $username, $dnPattern);
        } else {
            $searchUsername = $this->ldapConfig->getString('search.username');
            Assert::notWhitespaceOnly($searchUsername);

            $searchPassword = $this->ldapConfig->getString('search.password', null);
            Assert::nullOrnotWhitespaceOnly($searchPassword);

            $searchAttributes = $this->ldapConfig->getArray('search.attributes');
            $searchFilter = $this->ldapConfig->getString('search.filter', null);

            $ldap = $this->bind($ldapServers, $searchUsername, $searchPassword);

            $filter = '';
            foreach ($searchAttributes as $attr) {
                $filter .= '(' . $attr . '=' . $username . ')';
            }
            $filter = '(|' . $filter . ')';

            // Append LDAP filters if defined
            if ($searchFilter !== null) {
                $filter = "(&" . $filter . $searchFilter . ")";
            }

            /** @psalm-var \Symfony\Component\Ldap\Entry $entry */
            $entry = $this->search($ldap, $searchBase, $filter, $options, false);
            $dn = $entry->getDn();
        }

        $ldap = $this->bind($ldapServers, $dn, $password);
        $filter = sprintf('(distinguishedName=%s)', $dn);

        /** @psalm-var \Symfony\Component\Ldap\Entry $entry */
        $entry = $this->search($ldap, $searchBase, $filter, $options, false);

        $attributes = $this->ldapConfig->getArray('attributes', []);
        if ($attributes === ['*']) {
            $result = $entry->getAttributes();
        } else {
            $result = array_intersect_key(
                $entry->getAttributes(),
                array_fill_keys(array_values($attributes), null)
            );
        }

        $binaries = array_intersect(
            array_keys($result),
            $this->ldapConfig->getArray('attributes.binary', []),
        );
        foreach ($binaries as $binary) {
            $result[$binary] = array_map('base64_encode', $result[$binary]);
        }

        return $result;
    }


    /**
     * Bind to an LDAP-server
     *
     * @param \Symfony\Component\Ldap\Ldap[] $ldapServers
     * @param string $username
     * @param string|null $password  Null for passwordless logon
     * @throws \SimpleSAML\Error\Exception if none of the LDAP-servers could be contacted
     */
    private function bind(array $ldapServers, string $username, ?string $password)
    {
        foreach ($ldapServers as $ldap) {
            try {
                $ldap->bind($username, strval($password));
                return $ldap;
            } catch (ConnectionException $e) {
                // Try next server
            }
        }

        throw new Error\Exception("Unable to bind to any of the configured LDAP servers.");
    }


    /**
     * Search the LDAP-directory for a specific DN
     *
     * @param \Symfony\Component\Ldap\Ldap $ldap
     * @param array $searchBase
     * @param string $filter
     * @param array $options
     * @param boolean $allowMissing
     * @return \Symfony\Component\Ldap\Entry|null The result of the search or null if none found
     * @throws \SimpleSAML\Error\Exception if more than one entry was found
     * @throws \SimpleSAML\Error\Exception if the object cannot be found using the given search base and filter
     */
    private function search(
        LdapObject $ldap,
        array $searchBase,
        string $filter,
        array $options,
        bool $allowMissing
    ): ?Entry {
        $entry = null;

        foreach ($searchBase as $base) {
            $query = $ldap->query($base, $filter, $options);
            $result = $query->execute();
            $result = is_array($result) ? $result : $result->toArray();

            if (count($result) > 1) {
                throw new Error\Exception(
                    sprintf(
                        "Library - LDAP search(): Found %d entries searching base '%s' for '%s'",
                        count($result),
                        $base,
                        $filter,
                    )
                );
            } elseif (count($result) === 1) {
                $entry = array_pop($result);
                break;
            } else {
                Logger::debug(
                    sprintf(
                        "Library - LDAP search(): Found no entries searching base '%s' for '%s'",
                        count($result),
                        $base,
                        $filter,
                    )
                );
            }
        }

        if ($entry === null && $allowMissing === false) {
            throw new Error\Exception(
                sprintf(
                    "Object not found using search base [%s] and filter '%s'",
                    implode(', ', $searchBase),
                    $filter
                )
            );
        }

        return $entry;
    }
}