1 files changed, 89 insertions, 0 deletions
diff --git a/library/Icinga/Protocol/Dns.php b/library/Icinga/Protocol/Dns.php
new file mode 100644
index 0000000..3d422d7
--- /dev/null
+++ b/library/Icinga/Protocol/Dns.php
@@ -0,0 +1,89 @@
+<?php
+/* Icinga Web 2 | (c) 2014 Icinga Development Team | GPLv2+ */
+
+namespace Icinga\Protocol;
+
+/**
+ * Discover dns records using regular or reverse lookup
+ */
+class Dns
+{
+    /**
+     * Discover all service records on a given domain
+     *
+     * @param string    $domain     The domain to search
+     * @param string    $service    The type of the service, like for example 'ldaps' or 'ldap'
+     * @param string    $protocol   The transport protocol used by the service, defaults to 'tcp'
+     *
+     * @return array                An array of all found service records
+     */
+    public static function getSrvRecords($domain, $service, $protocol = 'tcp')
+    {
+        $records = dns_get_record('_' . $service . '._' . $protocol . '.' . $domain, DNS_SRV);
+        return $records === false ? array() : $records;
+    }
+
+    /**
+     * Get all ldap records for the given domain
+     *
+     * @param   string  $query    The domain to query
+     * @param   int     $type     The type of DNS-entry to fetch, see
+     *                            http://www.php.net/manual/de/function.dns-get-record.php for available types
+     *
+     * @return  array|null        An array of record entries
+     */
+    public static function records($query, $type = DNS_ANY)
+    {
+        return dns_get_record($query, $type);
+    }
+
+    /**
+     * Reverse lookup all host names available on the given ip address
+     *
+     * @param   string  $ipAddress
+     * @param   int     $type
+     *
+     * @return array|null
+     */
+    public static function ptr($ipAddress, $type = DNS_ANY)
+    {
+        $host = gethostbyaddr($ipAddress);
+        if ($host === false || $host === $ipAddress) {
+            // malformed input or no host found
+            return null;
+        }
+        return self::records($host, $type);
+    }
+
+    /**
+     * Get the IPv4 address of the given hostname.
+     *
+     * @param   $hostname       The hostname to resolve
+     *
+     * @return  string|null     The IPv4 address of the given hostname or null, when no entry exists.
+     */
+    public static function ipv4($hostname)
+    {
+        $records = dns_get_record($hostname, DNS_A);
+        if ($records !== false && count($records) > 0) {
+            return $records[0]['ip'];
+        }
+        return null;
+    }
+
+    /**
+     * Get the IPv6 address of the given hostname.
+     *
+     * @param   $hostname       The hostname to resolve
+     *
+     * @return  string|null     The IPv6 address of the given hostname or null, when no entry exists.
+     */
+    public static function ipv6($hostname)
+    {
+        $records = dns_get_record($hostname, DNS_AAAA);
+        if ($records !== false && count($records) > 0) {
+            return $records[0]['ip'];
+        }
+        return null;
+    }
+}