Merge pull request #26 from skirmis/feature/add-caa-type

Rdata: add new CAA record type and unit test

lib/Rdata/CAA.php

+<?php
+
+/*
+ * This file is part of Badcow DNS Library.
+ *
+ * (c) Samuel Williams <sam@badcow.co>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Badcow\DNS\Rdata;
+
+/**
+ * Class CaaRdata.
+ *
+ * CAA is defined in RFC 6844
+ *
+ * @see https://tools.ietf.org/html/rfc6844
+ *
+ * @author Samuel Williams <sam@badcow.co>
+ */
+class CAA extends CNAME
+{
+    const TYPE = 'CAA';
+
+    const MAX_FLAG = 255;
+
+    const ALLOWED_TAGS = ['issue', 'issuewild', 'iodef'];
+
+    /**
+     * It is currently used to represent the critical flag
+     *
+     * @var int
+     */
+    private $flag;
+
+    /**
+     * An ASCII string that represents the identifier of the property represented by the record.
+     * The RFC currently defines 3 available tags:
+     *  - issue: explicity authorizes a single certificate authority to issue a certificate (any type) for the hostname.
+     *  - issuewild: explicity authorizes a single certificate authority to issue a wildcard certificate (and only wildcard) for the hostname.
+     *  - iodef: specifies a URL to which a certificate authority may report policy violations.
+     *
+     * @var string
+     */
+    private $tag;
+
+    /**
+     * @return int
+     */
+    public function getFlag(): ?int
+    {
+        return $this->flag;
+    }
+
+    /**
+     * @param int $flag
+     *
+     * @throws \InvalidArgumentException
+     */
+    public function setFlag(int $flag): void
+    {
+        if ($flag < 0 || $flag > static::MAX_FLAG) {
+            throw new \InvalidArgumentException('Flag must be an unsigned integer on the range [0-255]');
+        }
+
+        $this->flag = $flag;
+    }
+
+    /**
+     * @return int
+     */
+    public function getTag(): ?string
+    {
+        return $this->tag;
+    }
+
+    /**
+     * @param int $tag
+     *
+     * @throws \InvalidArgumentException
+     */
+    public function setTag(string $tag): void
+    {
+        if (!in_array($tag, static::ALLOWED_TAGS)) {
+            throw new \InvalidArgumentException('Tag can be one of this type '.implode(' ', static::ALLOWED_TAGS));
+        }
+
+        $this->tag = $tag;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function output(): string
+    {
+        return sprintf('%s %s "%s"',
+            $this->flag,
+            $this->tag,
+            $this->target
+        );
+    }
+}

lib/Rdata/Factory.php

@@ -352,4 +352,21 @@ class Factory
 
         return $rdata;
     }
+
+    /**
+     * @param integer $flag
+     * @param string  $tag
+     * @param string  $target
+     *
+     * @return CAA
+     */
+    public static function Caa($flag, $tag, $target)
+    {
+        $rdata = new CAA();
+        $rdata->setFlag($flag);
+        $rdata->setTag($tag);
+        $rdata->setTarget($target);
+
+        return $rdata;
+    }
 }

lib/Tests/Rdata/CaaRdataTest.php

+<?php
+
+/*
+ * This file is part of Badcow DNS Library.
+ *
+ * (c) Samuel Williams <sam@badcow.co>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Badcow\DNS\Tests\Rdata;
+
+use Badcow\DNS\Rdata\CAA;
+use Badcow\DNS\Rdata\Factory;
+
+class CaaRdataTest extends \PHPUnit\Framework\TestCase
+{
+    public function testOutput()
+    {
+        $caa = Factory::Caa(0, 'issue', 'letsencrypt.org');
+
+        $expectation = '0 issue "letsencrypt.org"';
+
+        $this->assertEquals($expectation, $caa->output());
+        $this->assertEquals(0, $caa->getFlag());
+        $this->assertEquals('issue', $caa->getTag());
+    }
+
+    /**
+     * @expectedException \InvalidArgumentException
+     */
+    public function testFlagException()
+    {
+        $srv = new CAA();
+        $srv->setFlag(CAA::MAX_FLAG + 1);
+    }
+
+    /**
+     * @expectedException \InvalidArgumentException
+     */
+    public function testTagException()
+    {
+        $srv = new CAA();
+        $srv->setTag('not_exist');
+    }
+}