ACFで、内容が保存時に暗号化されるフィールド。需要は知らない。

acf-encrypted_field.php

<?php
/*
Plugin Name: Advanced Custom Fields: encrypted_field
Version: 1.0.0
Author: Toro_Unit
Author URI: http://www.jbnet.jp
License: GPLv2 or later
License URI: http://www.gnu.org/licenses/gpl-2.0.html
*/


class acf_field_encrypted_field_plugin
{
    /*
	*  Construct
	*
	*  @description:
	*  @since: 3.6
	*  @created: 1/04/13
	*/

	function __construct()
	{
		// set text domain
		/*
		$domain = 'acf-encrypted_field';
		$mofile = trailingslashit(dirname(__File__)) . 'lang/' . $domain . '-' . get_locale() . '.mo';
		load_textdomain( $domain, $mofile );
		*/


		// version 4+
		add_action('acf/register_fields', array($this, 'register_fields'));


		// version 3-
		//add_action( 'init', array( $this, 'init' ), 5);
	}


	/*
	*  Init
	*
	*  @description:
	*  @since: 3.6
	*  @created: 1/04/13
	*/

	function init()
	{
		if(function_exists('register_field'))
		{
			register_field('acf_field_encrypted_field', dirname(__File__) . '/encrypted_field-v3.php');
		}
	}

	/*
	*  register_fields
	*
	*  @description:
	*  @since: 3.6
	*  @created: 1/04/13
	*/

	function register_fields()
	{
		include_once('encrypted_field-v4.php');
	}

}

new acf_field_encrypted_field_plugin();

?>

encrypted_field-v4.php

<?php

class acf_field_encrypted_field extends acf_field
{
    // vars
	var $settings, // will hold info such as dir / path
		$defaults, // will hold default field options
		$key,
		$iv,
		$resource;

	public function __construct()
	{
		// vars
		$this->name = 'encrypted_field';
		$this->label = __('encrypted field');
		$this->category = __("Basic",'acf'); // Basic, Content, Choice, etc

		// do not delete!
    	parent::__construct();

    	// settings
		$this->settings = array(
			'path' => apply_filters('acf/helpers/get_path', __FILE__),
			'dir' => apply_filters('acf/helpers/get_dir', __FILE__),
			'version' => '1.0.0'
		);
	}


	public function create_options( $field )
	{
		$key = $field['name'];
		?>
		<tr class="field_option field_option_<?php echo $this->name; ?>">
			<td class="label">
				<label><?php _e("Key Strings",'acf'); ?></label>
			</td>
			<td>
				<?php
				do_action('acf/create_field', array(
					'type'	=>	'text',
					'name'	=>	'fields['.$key.'][key_string]',
					'value'	=>	$field['key_string'],
				));
				?>
			</td>
		</tr>
		<?php
	}


	public function create_field( $field ) {
		echo '<input type="text" value="' . esc_attr( $field['value'] ) . '" id="' . esc_attr( $field['id'] ) . '" class="' . esc_attr( $field['class'] ) . '" name="' . esc_attr( $field['name'] ) . '" />';
	}


	public function load_value( $value, $post_id, $field ) {
		$value = $this->_decrypt( $value ,$field['key_string']);
		return $value;
	}


	public function update_value( $value, $post_id, $field ) {
		$value = $this->_encrypt( $value ,$field['key_string']);
		return $value;
	}

	protected function mcript_open($key) {
		$td  = mcrypt_module_open('des', '', 'ecb', '');
		$key = substr($key, 0, mcrypt_enc_get_key_size($td));
		$iv  = mcrypt_create_iv(mcrypt_enc_get_iv_size($td), MCRYPT_RAND);

		if (mcrypt_generic_init($td, $key, $iv) < 0) {
			exit('error.');
		}

		return $td;
	}

	protected function mcrypt_close( $td ) {
		mcrypt_generic_deinit($td);
		mcrypt_module_close($td);
	}


	protected function _encrypt( $input, $key ) {

		$td = $this->mcript_open($key);
		$encrypt_text = base64_encode(mcrypt_generic($td, $input));
		$this->mcrypt_close($td);

		return $encrypt_text;
	}

	protected function _decrypt( $input, $key ) {
		if( !$input ) {
			return $input;
		}
		$td = $this->mcript_open($key);
		$decrypt_text = mdecrypt_generic($td, base64_decode( $input ));
		$this->mcrypt_close($td);

		return str_replace("\0", "", $decrypt_text);

	}


}


// create field
new acf_field_encrypted_field();

?>