<?php
/* vim: set expandtab tabstop=4 shiftwidth=4 softtabstop=4: */

/**
 * DNS Library for handling lookups and updates. 
 *
 * PHP Version 5
 *
 * Copyright (c) 2012, Mike Pultz <mike@mikepultz.com>.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *   * Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *
 *   * Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in
 *     the documentation and/or other materials provided with the
 *     distribution.
 *
 *   * Neither the name of Mike Pultz nor the names of his contributors 
 *     may be used to endorse or promote products derived from this 
 *     software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRIC
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 * @category  Networking
 * @package   Net_DNS2
 * @author    Mike Pultz <mike@mikepultz.com>
 * @copyright 2012 Mike Pultz <mike@mikepultz.com>
 * @license   http://www.opensource.org/licenses/bsd-license.php  BSD License
 * @version   SVN: $Id: TLSA.php 198 2013-05-26 05:05:22Z mike.pultz $
 * @link      http://pear.php.net/package/Net_DNS2
 * @since     File available since Release 1.2.5
 *
 */

/**
 * TLSA Resource Record - RFC 6698
 *
 *   0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *  |  Cert. Usage  |   Selector    | Matching Type |               /
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+               /
 *  /                                                               /
 *  /                 Certificate Association Data                  /
 *  /                                                               /
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 * 
 * @category Networking
 * @package  Net_DNS2
 * @author   Mike Pultz <mike@mikepultz.com>
 * @license  http://www.opensource.org/licenses/bsd-license.php  BSD License
 * @link     http://pear.php.net/package/Net_DNS2
 * @see      Net_DNS2_RR
 *
 */
class Net_DNS2_RR_TLSA extends Net_DNS2_RR
{
    /*
     * The Certificate Usage Field
     */
    public $cert_usage;

    /*
     * The Selector Field
     */
    public $selector;

    /*
     * The Matching Type Field
     */
    public $matching_type;

    /*
     * The Certificate Association Data Field
     */
    public $certificate;

    /**
     * method to return the rdata portion of the packet as a string
     *
     * @return  string
     * @access  protected
     *
     */
    protected function rrToString()
    {
        return $this->cert_usage . ' ' . $this->selector . ' ' . 
            $this->matching_type . ' ' . base64_encode($this->certificate);
    }

    /**
     * parses the rdata portion from a standard DNS config line
     *
     * @param array $rdata a string split line of values for the rdata
     *
     * @return boolean
     * @access protected
     *
     */
    protected function rrFromString(array $rdata)
    {
        $this->cert_usage       = array_shift($rdata);
        $this->selector         = array_shift($rdata);
        $this->matching_type    = array_shift($rdata);
        $this->certificate      = base64_decode(implode('', $rdata));

        return true;
    }

    /**
     * parses the rdata of the Net_DNS2_Packet object
     *
     * @param Net_DNS2_Packet &$packet a Net_DNS2_Packet packet to parse the RR from
     *
     * @return boolean
     * @access protected
     *
     */
    protected function rrSet(Net_DNS2_Packet &$packet)
    {
        if ($this->rdlength > 0) {

            //
            // unpack the format, keytag and algorithm
            //
            $x = unpack('Cusage/Cselector/Ctype', $this->rdata);

            $this->cert_usage       = $x['usage'];
            $this->selector         = $x['selector'];
            $this->matching_type    = $x['type'];

            //
            // copy the certificate
            //
            $this->certificate  = substr($this->rdata, 3, $this->rdlength - 3);

            return true;
        }

        return false;
    }

    /**
     * returns the rdata portion of the DNS packet
     *
     * @param Net_DNS2_Packet &$packet a Net_DNS2_Packet packet use for
     *                                 compressed names
     *
     * @return mixed                   either returns a binary packed
     *                                 string or null on failure
     * @access protected
     *
     */
    protected function rrGet(Net_DNS2_Packet &$packet)
    {
        if (strlen($this->certificate) > 0) {

            $data = pack(
                'CCC', $this->cert_usage, $this->selector, $this->matching_type
            ) . $this->certificate;

            $packet->offset += strlen($data);

            return $data;
        }

        return null;
    }
}

/*
 * Local variables:
 * tab-width: 4
 * c-basic-offset: 4
 * c-hanging-comment-ender-p: nil
 * End:
 */
?>
