4 files changed, 283 insertions, 0 deletions
diff --git a/library/Icinga/Web/Helper/CookieHelper.php b/library/Icinga/Web/Helper/CookieHelper.php
new file mode 100644
index 0000000..cc7c448
--- /dev/null
+++ b/library/Icinga/Web/Helper/CookieHelper.php
@@ -0,0 +1,81 @@
+<?php
+/* Icinga Web 2 | (c) 2013 Icinga Development Team | GPLv2+ */
+
+namespace Icinga\Web\Helper;
+
+use Icinga\Web\Request;
+
+/**
+ * Helper Class Cookie
+ */
+class CookieHelper
+{
+    /**
+     * The name of the control cookie
+     */
+    const CHECK_COOKIE = '_chc';
+
+    /**
+     * The request
+     *
+     * @var Request
+     */
+    protected $request;
+
+    /**
+     * Create a new cookie
+     *
+     * @param Request $request
+     */
+    public function __construct(Request $request)
+    {
+        $this->request = $request;
+    }
+
+    /**
+     * Check whether cookies are supported or not
+     *
+     * @return bool
+     */
+    public function isSupported()
+    {
+        if (! empty($_COOKIE)) {
+            $this->cleanupCheck();
+            return true;
+        }
+
+        $url = $this->request->getUrl();
+
+        if ($url->hasParam('_checkCookie') && empty($_COOKIE)) {
+            return false;
+        }
+
+        if (! $url->hasParam('_checkCookie')) {
+            $this->provideCheck();
+        }
+
+        return false;
+    }
+
+    /**
+     * Prepare check to detect cookie support
+     */
+    public function provideCheck()
+    {
+        setcookie(self::CHECK_COOKIE, '1');
+
+        $requestUri = $this->request->getUrl()->addParams(array('_checkCookie' => 1));
+        $this->request->getResponse()->redirectAndExit($requestUri);
+    }
+
+    /**
+     * Cleanup the cookie support check
+     */
+    public function cleanupCheck()
+    {
+        if ($this->request->getUrl()->hasParam('_checkCookie') && isset($_COOKIE[self::CHECK_COOKIE])) {
+            $requestUri =$this->request->getUrl()->without('_checkCookie');
+            $this->request->getResponse()->redirectAndExit($requestUri);
+        }
+    }
+}
diff --git a/library/Icinga/Web/Helper/HtmlPurifier.php b/library/Icinga/Web/Helper/HtmlPurifier.php
new file mode 100644
index 0000000..19fd207
--- /dev/null
+++ b/library/Icinga/Web/Helper/HtmlPurifier.php
@@ -0,0 +1,95 @@
+<?php
+/* Icinga Web 2 | (c) 2018 Icinga Development Team | GPLv2+ */
+
+namespace Icinga\Web\Helper;
+
+use Closure;
+use Icinga\Web\FileCache;
+use InvalidArgumentException;
+
+class HtmlPurifier
+{
+    /**
+     * The actual purifier instance
+     *
+     * @var \HTMLPurifier
+     */
+    protected $purifier;
+
+    /**
+     * Create a new HtmlPurifier
+     *
+     * @param   array|Closure   $config     Additional configuration
+     */
+    public function __construct($config = null)
+    {
+        $purifierConfig = \HTMLPurifier_Config::createDefault();
+        $purifierConfig->set('Core.EscapeNonASCIICharacters', true);
+        $purifierConfig->set('Attr.AllowedFrameTargets', array('_blank'));
+
+        if (($cachePath = FileCache::instance()->directory('htmlpurifier.cache')) !== false) {
+            $purifierConfig->set('Cache.SerializerPath', $cachePath);
+        } else {
+            $purifierConfig->set('Cache.DefinitionImpl', null);
+        }
+
+        // This avoids permission problems:
+        // $purifierConfig->set('Core.DefinitionCache', null);
+
+        // $purifierConfig->set('URI.Base', 'http://www.example.com');
+        // $purifierConfig->set('URI.MakeAbsolute', true);
+
+        $this->configure($purifierConfig);
+
+        if ($config instanceof Closure) {
+            call_user_func($config, $purifierConfig);
+        } elseif (is_array($config)) {
+            $purifierConfig->loadArray($config);
+        } elseif ($config !== null) {
+            throw new InvalidArgumentException('$config must be either a Closure or array');
+        }
+
+        $this->purifier = new \HTMLPurifier($purifierConfig);
+    }
+
+    /**
+     * Apply additional default configuration
+     *
+     * May be overwritten by more concrete purifier implementations.
+     *
+     * @param   \HTMLPurifier_Config    $config
+     */
+    protected function configure($config)
+    {
+    }
+
+    /**
+     * Purify and return the given HTML string
+     *
+     * @param   string          $html
+     * @param   array|Closure   $config     Configuration to use instead of the default
+     *
+     * @return  string
+     */
+    public function purify($html, $config = null)
+    {
+        return $this->purifier->purify($html, $config);
+    }
+
+    /**
+     * Purify and return the given HTML string
+     *
+     * Convenience method to bypass object creation.
+     *
+     * @param   string          $html
+     * @param   array|Closure   $config     Additional configuration
+     *
+     * @return  string
+     */
+    public static function process($html, $config = null)
+    {
+        $purifier = new static($config);
+
+        return $purifier->purify($html);
+    }
+}
diff --git a/library/Icinga/Web/Helper/Markdown.php b/library/Icinga/Web/Helper/Markdown.php
new file mode 100644
index 0000000..cb854b4
--- /dev/null
+++ b/library/Icinga/Web/Helper/Markdown.php
@@ -0,0 +1,34 @@
+<?php
+/* Icinga Web 2 | (c) 2019 Icinga GmbH | GPLv2+ */
+
+namespace Icinga\Web\Helper;
+
+use Icinga\Web\Helper\Markdown\LinkTransformer;
+use Parsedown;
+
+class Markdown
+{
+    public static function line($content, $config = null)
+    {
+        if ($config === null) {
+            $config = function (\HTMLPurifier_Config $config) {
+                $config->set('HTML.Parent', 'span'); // Only allow inline elements
+
+                LinkTransformer::attachTo($config);
+            };
+        }
+
+        return HtmlPurifier::process(Parsedown::instance()->line($content), $config);
+    }
+
+    public static function text($content, $config = null)
+    {
+        if ($config === null) {
+            $config = function (\HTMLPurifier_Config $config) {
+                LinkTransformer::attachTo($config);
+            };
+        }
+
+        return HtmlPurifier::process(Parsedown::instance()->text($content), $config);
+    }
+}
diff --git a/library/Icinga/Web/Helper/Markdown/LinkTransformer.php b/library/Icinga/Web/Helper/Markdown/LinkTransformer.php
new file mode 100644
index 0000000..f323085
--- /dev/null
+++ b/library/Icinga/Web/Helper/Markdown/LinkTransformer.php
@@ -0,0 +1,73 @@
+<?php
+/* Icinga Web 2 | (c) 2021 Icinga GmbH | GPLv2+ */
+
+namespace Icinga\Web\Helper\Markdown;
+
+use HTMLPurifier_AttrTransform;
+use HTMLPurifier_Config;
+use ipl\Web\Url;
+
+class LinkTransformer extends HTMLPurifier_AttrTransform
+{
+    /**
+     * Link targets that are considered to have a thumbnail
+     *
+     * @var string[]
+     */
+    public static $IMAGE_FILES = [
+        'jpg',
+        'jpeg',
+        'png',
+        'bmp',
+        'gif',
+        'heif',
+        'heic',
+        'webp'
+    ];
+
+    public function transform($attr, $config, $context)
+    {
+        if (! isset($attr['href'])) {
+            return $attr;
+        }
+
+        $url = Url::fromPath($attr['href']);
+        $fileName = basename($url->getPath());
+
+        $ext = null;
+        if (($extAt = strrpos($fileName, '.')) !== false) {
+            $ext = substr($fileName, $extAt + 1);
+        }
+
+        $hasThumbnail = $ext !== null && in_array($ext, static::$IMAGE_FILES, true);
+        if ($hasThumbnail) {
+            // I would have liked to not only base this off of the extension, but also by
+            // whether there is an actual img tag inside the anchor. Seems not possible :(
+            $attr['class'] = 'with-thumbnail';
+        }
+
+        if (! isset($attr['target'])) {
+            if ($url->isExternal()) {
+                $attr['target'] = '_blank';
+            } else {
+                $attr['data-base-target'] = '_next';
+            }
+        }
+
+        return $attr;
+    }
+
+    public static function attachTo(HTMLPurifier_Config $config)
+    {
+        $module = $config->getHTMLDefinition(true)
+            ->getAnonymousModule();
+
+        if (isset($module->info['a'])) {
+            $a = $module->info['a'];
+        } else {
+            $a = $module->addBlankElement('a');
+        }
+
+        $a->attr_transform_post[] = new self();
+    }
+}