<?php
/**
*
* @package VC
* @version $Id$
* @copyright (c) 2006, 2008 phpBB Group
* @license http://opensource.org/licenses/gpl-license.php GNU Public License
*
*/
/**
* @ignore
*/
if (!defined('IN_PHPBB'))
{
exit;
}
global $table_prefix;
define('CAPTCHA_QUESTIONS_TABLE', $table_prefix . 'captcha_questions');
define('CAPTCHA_ANSWERS_TABLE', $table_prefix . 'captcha_answers');
define('CAPTCHA_QA_CONFIRM_TABLE', $table_prefix . 'qa_confirm');
/**
* And now to something completely different. Let's make a captcha without extending the abstract class.
* QA CAPTCHA sample implementation
*
* @package VC
*/
class phpbb_captcha_qa
{
var $confirm_id;
var $answer;
var $question_ids;
var $question_text;
var $question_lang;
var $question_strict;
var $attempts = 0;
var $type;
// dirty trick: 0 is false, but can still encode that the captcha is not yet validated
var $solved = 0;
/**
* @param int $type as per the CAPTCHA API docs, the type
*/
function init($type)
{
global $config, $db, $user;
// load our language file
$user->add_lang('captcha_qa');
// read input
$this->confirm_id = request_var('qa_confirm_id', '');
$this->answer = utf8_normalize_nfc(request_var('qa_answer', '', true));
$this->type = (int) $type;
$this->question_lang = $user->lang_name;
// we need all defined questions - shouldn't be too many, so we can just grab them
// try the user's lang first
$sql = 'SELECT question_id
FROM ' . CAPTCHA_QUESTIONS_TABLE . "
WHERE lang_iso = '" . $db->sql_escape($user->lang_name) . "'";
$result = $db->sql_query($sql, 3600);
while ($row = $db->sql_fetchrow($result))
{
$this->question_ids[$row['question_id']] = $row['question_id'];
}
$db->sql_freeresult($result);
// fallback to the board default lang
if (!sizeof($this->question_ids))
{
$this->question_lang = $config['default_lang'];
$sql = 'SELECT question_id
FROM ' . CAPTCHA_QUESTIONS_TABLE . "
WHERE lang_iso = '" . $db->sql_escape($config['default_lang']) . "'";
$result = $db->sql_query($sql, 7200);
while ($row = $db->sql_fetchrow($result))
{
$this->question_ids[$row['question_id']] = $row['question_id'];
}
$db->sql_freeresult($result);
}
// okay, if there is a confirm_id, we try to load that confirm's state. If not, we try to find one
if (!$this->load_answer() && (!$this->load_confirm_id() || !$this->load_answer()))
{
// we have no valid confirm ID, better get ready to ask something
$this->select_question();
}
}
/**
* API function
*/
function &get_instance()
{
$instance =& new phpbb_captcha_qa();
return $instance;
}
/**
* See if the captcha has created its tables.
*/
function is_installed()
{
global $db, $phpbb_root_path, $phpEx;
if (!class_exists('phpbb_db_tools'))
{
include("$phpbb_root_path/includes/db/db_tools.$phpEx");
}
$db_tool = new phpbb_db_tools($db);
return $db_tool->sql_table_exists(CAPTCHA_QUESTIONS_TABLE);
}
/**
* API function - for the captcha to be available, it must have installed itself and there has to be at least one question in the board's default lang
*/
function is_available()
{
global $config, $db, $phpbb_root_path, $phpEx, $user;
// load language file for pretty display in the ACP dropdown
$user->add_lang('captcha_qa');
if (!phpbb_captcha_qa::is_installed())
{
return false;
}
$sql = 'SELECT COUNT(question_id) AS question_count
FROM ' . CAPTCHA_QUESTIONS_TABLE . "
WHERE lang_iso = '" . $db->sql_escape($config['default_lang']) . "'";
$result = $db->sql_query($sql);
$row = $db->sql_fetchrow($result);
$db->sql_freeresult($result);
return ((bool) $row['question_count']);
}
/**
* API function
*/
function has_config()
{
return true;
}
/**
* API function
*/
function get_name()
{
return 'CAPTCHA_QA';
}
/**
* API function
*/
function get_class_name()
{
return 'phpbb_captcha_qa';
}
/**
* API function - not needed as we don't display an image
*/
function execute_demo()
{
}
/**
* API function - not needed as we don't display an image
*/
function execute()
{
}
/**
* API function - send the question to the template
*/
function get_template()
{
global $template;
if ($this->is_solved())
{
return false;
}
else
{
$template->assign_vars(array(
'QA_CONFIRM_QUESTION' => $this->question_text,
'QA_CONFIRM_ID' => $this->confirm_id,
'S_CONFIRM_CODE' => true,
'S_TYPE' => $this->type,
));
return 'captcha_qa.html';
}
}
/**
* API function - we just display a mockup so that the captcha doesn't need to be installed
*/
function get_demo_template()
{
global $config, $db, $template;
if ($this->is_available())
{
$sql = 'SELECT question_text
FROM ' . CAPTCHA_QUESTIONS_TABLE . "
WHERE lang_iso = '" . $db->sql_escape($config['default_lang']) . "'";
$result = $db->sql_query_limit($sql, 1);
if ($row = $db->sql_fetchrow($result))
{
$template->assign_vars(array(
'QA_CONFIRM_QUESTION' => $row['question_text'],
));
}
$db->sql_freeresult($result);
}
return 'captcha_qa_acp_demo.html';
}
/**
* API function
*/
function get_hidden_fields()
{
$hidden_fields = array();
// this is required - otherwise we would forget about the captcha being already solved
if ($this->solved)
{
$hidden_fields['qa_answer'] = $this->answer;
}
$hidden_fields['qa_confirm_id'] = $this->confirm_id;
return $hidden_fields;
}
/**
* API function
*/
function garbage_collect($type = 0)
{
global $db, $config;
$sql = 'SELECT c.confirm_id
FROM ' . CAPTCHA_QA_CONFIRM_TABLE . ' c
LEFT JOIN ' . SESSIONS_TABLE . ' s
ON (c.session_id = s.session_id)
WHERE s.session_id IS NULL' .
((empty($type)) ? '' : ' AND c.confirm_type = ' . (int) $type);
$result = $db->sql_query($sql);
if ($row = $db->sql_fetchrow($result))
{
$sql_in = array();
do
{
$sql_in[] = (string) $row['confirm_id'];
}
while ($row = $db->sql_fetchrow($result));
if (sizeof($sql_in))
{
$sql = 'DELETE FROM ' . CAPTCHA_QA_CONFIRM_TABLE . '
WHERE ' . $db->sql_in_set('confirm_id', $sql_in);
$db->sql_query($sql);
}
}
$db->sql_freeresult($result);
}
/**
* API function - we don't drop the tables here, as that would cause the loss of all entered questions.
*/
function uninstall()
{
$this->garbage_collect(0);
}
/**
* API function - set up shop
*/
function install()
{
global $db, $phpbb_root_path, $phpEx;
if (!class_exists('phpbb_db_tools'))
{
include("$phpbb_root_path/includes/db/db_tools.$phpEx");
}
$db_tool = new phpbb_db_tools($db);
$tables = array(CAPTCHA_QUESTIONS_TABLE, CAPTCHA_ANSWERS_TABLE, CAPTCHA_QA_CONFIRM_TABLE);
$schemas = array(
CAPTCHA_QUESTIONS_TABLE => array (
'COLUMNS' => array(
'question_id' => array('UINT', Null, 'auto_increment'),
'strict' => array('BOOL', 0),
'lang_id' => array('UINT', 0),
'lang_iso' => array('VCHAR:30', ''),
'question_text' => array('TEXT_UNI', ''),
),
'PRIMARY_KEY' => 'question_id',
'KEYS' => array(
'lang' => array('INDEX', 'lang_iso'),
),
),
CAPTCHA_ANSWERS_TABLE => array (
'COLUMNS' => array(
'question_id' => array('UINT', 0),
'answer_text' => array('STEXT_UNI', ''),
),
'KEYS' => array(
'qid' => array('INDEX', 'question_id'),
),
),
CAPTCHA_QA_CONFIRM_TABLE => array (
'COLUMNS' => array(
'session_id' => array('CHAR:32', ''),
'confirm_id' => array('CHAR:32', ''),
'lang_iso' => array('VCHAR:30', ''),
'question_id' => array('UINT', 0),
'attempts' => array('UINT', 0),
'confirm_type' => array('USINT', 0),
),
'KEYS' => array(
'session_id' => array('INDEX', 'session_id'),
'lookup' => array('INDEX', array('confirm_id', 'session_id', 'lang_iso')),
),
'PRIMARY_KEY' => 'confirm_id',
),
);
foreach($schemas as $table => $schema)
{
if (!$db_tool->sql_table_exists($table))
{
$db_tool->sql_create_table($table, $schema);
}
}
}
/**
* API function - see what has to be done to validate
*/
function validate()
{
global $config, $db, $user;
$error = '';
if (!sizeof($this->question_ids))
{
return false;
}
if (!$this->confirm_id)
{
$error = $user->lang['CONFIRM_QUESTION_WRONG'];
}
else
{
if ($this->check_answer())
{
// $this->delete_code(); commented out to allow posting.php to repeat the question
$this->solved = true;
}
else
{
$error = $user->lang['CONFIRM_QUESTION_WRONG'];
}
}
if (strlen($error))
{
// okay, incorrect answer. Let's ask a new question.
$this->new_attempt();
$this->solved = false;
return $error;
}
else
{
return false;
}
}
/**
* Select a question
*/
function select_question()
{
global $db, $user;
if (!sizeof($this->question_ids))
{
return false;
}
$this->confirm_id = md5(unique_id($user->ip));
$this->question = (int) array_rand($this->question_ids);
$sql = 'INSERT INTO ' . CAPTCHA_QA_CONFIRM_TABLE . ' ' . $db->sql_build_array('INSERT', array(
'confirm_id' => (string) $this->confirm_id,
'session_id' => (string) $user->session_id,
'lang_iso' => (string) $this->question_lang,
'confirm_type' => (int) $this->type,
'question_id' => (int) $this->question,
));
$db->sql_query($sql);
$this->load_answer();
}
/**
* New Question, if desired.
*/
function reselect_question()
{
global $db, $user;
if (!sizeof($this->question_ids))
{
return false;
}
$this->question = (int) array_rand($this->question_ids);
$this->solved = 0;
$sql = 'UPDATE ' . CAPTCHA_QA_CONFIRM_TABLE . '
SET question_id = ' . (int) $this->question . "
WHERE confirm_id = '" . $db->sql_escape($this->confirm_id) . "'
AND session_id = '" . $db->sql_escape($user->session_id) . "'";
$db->sql_query($sql);
$this->load_answer();
}
/**
* Wrong answer, so we increase the attempts and use a different question.
*/
function new_attempt()
{
global $db, $user;
// yah, I would prefer a stronger rand, but this should work
$this->question = (int) array_rand($this->question_ids);
$this->solved = 0;
$sql = 'UPDATE ' . CAPTCHA_QA_CONFIRM_TABLE . '
SET question_id = ' . (int) $this->question . ",
attempts = attempts + 1
WHERE confirm_id = '" . $db->sql_escape($this->confirm_id) . "'
AND session_id = '" . $db->sql_escape($user->session_id) . "'";
$db->sql_query($sql);
$this->load_answer();
}
/**
* See if there is already an entry for the current session.
*/
function load_confirm_id()
{
global $db, $user;
$sql = 'SELECT confirm_id
FROM ' . CAPTCHA_QA_CONFIRM_TABLE . "
WHERE
session_id = '" . $db->sql_escape($user->session_id) . "'
AND lang_iso = '" . $db->sql_escape($this->question_lang) . "'
AND confirm_type = " . $this->type;
$result = $db->sql_query_limit($sql, 1);
$row = $db->sql_fetchrow($result);
$db->sql_freeresult($result);
if ($row)
{
$this->confirm_id = $row['confirm_id'];
return true;
}
return false;
}
/**
* Look up everything we need and populate the instance variables.
*/
function load_answer()
{
global $db, $user;
if (!strlen($this->confirm_id) || !sizeof($this->question_ids))
{
return false;
}
$sql = 'SELECT con.question_id, attempts, question_text, strict
FROM ' . CAPTCHA_QA_CONFIRM_TABLE . ' con, ' . CAPTCHA_QUESTIONS_TABLE . " qes
WHERE con.question_id = qes.question_id
AND confirm_id = '" . $db->sql_escape($this->confirm_id) . "'
AND session_id = '" . $db->sql_escape($user->session_id) . "'
AND qes.lang_iso = '" . $db->sql_escape($this->question_lang) . "'
AND confirm_type = " . $this->type;
$result = $db->sql_query($sql);
$row = $db->sql_fetchrow($result);
$db->sql_freeresult($result);
if ($row)
{
$this->question = $row['question_id'];
$this->attempts = $row['attempts'];
$this->question_strict = $row['strict'];
$this->question_text = $row['question_text'];
return true;
}
return false;
}
/**
* The actual validation
*/
function check_answer()
{
global $db;
$answer = ($this->question_strict) ? utf8_normalize_nfc(request_var('qa_answer', '', true)) : utf8_clean_string(utf8_normalize_nfc(request_var('qa_answer', '', true)));
$sql = 'SELECT answer_text
FROM ' . CAPTCHA_ANSWERS_TABLE . '
WHERE question_id = ' . (int) $this->question;
$result = $db->sql_query($sql);
while ($row = $db->sql_fetchrow($result))
{
$solution = ($this->question_strict) ? $row['answer_text'] : utf8_clean_string($row['answer_text']);
if ($solution === $answer)
{
$this->solved = true;
break;
}
}
$db->sql_freeresult($result);
return $this->solved;
}
/**
* API function - clean the entry
*/
function delete_code()
{
global $db, $user;
$sql = 'DELETE FROM ' . CAPTCHA_QA_CONFIRM_TABLE . "
WHERE confirm_id = '" . $db->sql_escape($confirm_id) . "'
AND session_id = '" . $db->sql_escape($user->session_id) . "'
AND confirm_type = " . $this->type;
$db->sql_query($sql);
}
/**
* API function
*/
function get_attempt_count()
{
return $this->attempts;
}
/**
* API function
*/
function reset()
{
global $db, $user;
$sql = 'DELETE FROM ' . CAPTCHA_QA_CONFIRM_TABLE . "
WHERE session_id = '" . $db->sql_escape($user->session_id) . "'
AND confirm_type = " . (int) $this->type;
$db->sql_query($sql);
// we leave the class usable by generating a new question
$this->select_question();
}
/**
* API function
*/
function is_solved()
{
if (request_var('qa_answer', false) && $this->solved === 0)
{
$this->validate();
}
return (bool) $this->solved;
}
/**
* API function - The ACP backend, this marks the end of the easy methods
*/
function acp_page($id, &$module)
{
global $db, $user, $auth, $template;
global $config, $phpbb_root_path, $phpbb_admin_path, $phpEx;
$user->add_lang('acp/board');
$user->add_lang('captcha_qa');
if (!$this->is_installed())
{
$this->install();
}
$module->tpl_name = 'captcha_qa_acp';
$module->page_title = 'ACP_VC_SETTINGS';
$form_key = 'acp_captcha';
add_form_key($form_key);
$submit = request_var('submit', false);
$question_id = request_var('question_id', 0);
$action = request_var('action', '');
// we have two pages, so users might want to navigate from one to the other
$list_url = $module->u_action . "&configure=1&select_captcha=" . $this->get_class_name();
$template->assign_vars(array(
'U_ACTION' => $module->u_action,
'QUESTION_ID' => $question_id ,
'CLASS' => $this->get_class_name(),
));
// show the list?
if (!$question_id && $action != 'add')
{
$this->acp_question_list($module);
}
else if ($question_id && $action == 'delete')
{
if ($this->get_class_name() !== $config['captcha_plugin'] || !$this->acp_is_last($question_id))
{
if (confirm_box(true))
{
$this->acp_delete_question($question_id);
trigger_error($user->lang['QUESTION_DELETED'] . adm_back_link($list_url));
}
else
{
confirm_box(false, $user->lang['CONFIRM_OPERATION'], build_hidden_fields(array(
'question_id' => $question_id,
'action' => $action,
'configure' => 1,
'select_captcha' => $this->get_class_name(),
))
);
}
}
else
{
trigger_error($user->lang['QA_LAST_QUESTION'] . adm_back_link($list_url), E_USER_WARNING);
}
}
else
{
// okay, show the editor
$error = false;
$input_question = request_var('question_text', '', true);
$input_answers = request_var('answers', '', true);
$input_lang = request_var('lang_iso', '', true);
$input_strict = request_var('strict', false);
$langs = $this->get_languages();
foreach ($langs as $lang => $entry)
{
$template->assign_block_vars('langs', array(
'ISO' => $lang,
'NAME' => $entry['name'],
));
}
$template->assign_vars(array(
'U_LIST' => $list_url,
));
if ($question_id)
{
if ($question = $this->acp_get_question_data($question_id))
{
$answers = (isset($input_answers[$lang])) ? $input_answers[$lang] : implode("\n", $question['answers']);
$template->assign_vars(array(
'QUESTION_TEXT' => ($input_question) ? $input_question : $question['question_text'],
'LANG_ISO' => ($input_lang) ? $input_lang : $question['lang_iso'],
'STRICT' => (isset($_REQUEST['strict'])) ? $input_strict : $question['strict'],
'ANSWERS' => $answers,
));
}
else
{
trigger_error($user->lang['FORM_INVALID'] . adm_back_link($list_url));
}
}
else
{
$template->assign_vars(array(
'QUESTION_TEXT' => $input_question,
'LANG_ISO' => $input_lang,
'STRICT' => $input_strict,
'ANSWERS' => $input_answers,
));
}
if ($submit && check_form_key($form_key))
{
$data = $this->acp_get_question_input();
if (!$this->validate_input($data))
{
$template->assign_vars(array(
'S_ERROR' => true,
));
}
else
{
if ($question_id)
{
$this->acp_update_question($data, $question_id);
}
else
{
$this->acp_add_question($data);
}
add_log('admin', 'LOG_CONFIG_VISUAL');
trigger_error($user->lang['CONFIG_UPDATED'] . adm_back_link($list_url));
}
}
else if ($submit)
{
trigger_error($user->lang['FORM_INVALID'] . adm_back_link($list_url), E_USER_WARNING);
}
}
}
/**
* This handles the list overview
*/
function acp_question_list(&$module)
{
global $db, $template;
$sql = 'SELECT *
FROM ' . CAPTCHA_QUESTIONS_TABLE;
$result = $db->sql_query($sql);
$template->assign_vars(array(
'S_LIST' => true,
));
while ($row = $db->sql_fetchrow($result))
{
$url = $module->u_action . "&question_id={$row['question_id']}&configure=1&select_captcha=" . $this->get_class_name() . '&';
$template->assign_block_vars('questions', array(
'QUESTION_TEXT' => $row['question_text'],
'QUESTION_ID' => $row['question_id'],
'QUESTION_LANG' => $row['lang_iso'],
'U_DELETE' => "{$url}action=delete",
'U_EDIT' => "{$url}action=edit",
));
}
$db->sql_freeresult($result);
}
/**
* Grab a question and bring it into a format the editor understands
*/
function acp_get_question_data($question_id)
{
global $db;
if ($question_id)
{
$sql = 'SELECT *
FROM ' . CAPTCHA_QUESTIONS_TABLE . '
WHERE question_id = ' . $question_id;
$result = $db->sql_query($sql);
$question = $db->sql_fetchrow($result);
$db->sql_freeresult($result);
if (!$question)
{
return false;
}
$question['answers'] = array();
$sql = 'SELECT *
FROM ' . CAPTCHA_ANSWERS_TABLE . '
WHERE question_id = ' . $question_id;
$result = $db->sql_query($sql);
while ($row = $db->sql_fetchrow($result))
{
$question['answers'][] = $row['answer_text'];
}
$db->sql_freeresult($result);
return $question;
}
}
/**
* Grab a question from input and bring it into a format the editor understands
*/
function acp_get_question_input()
{
$answers = utf8_normalize_nfc(request_var('answers', '', true));
$question = array(
'question_text' => request_var('question_text', '', true),
'strict' => request_var('strict', false),
'lang_iso' => request_var('lang_iso', ''),
'answers' => (strlen($answers)) ? explode("\n", $answers) : '',
);
return $question;
}
/**
* Update a question.
* param mixed $data : an array as created from acp_get_question_input or acp_get_question_data
*/
function acp_update_question($data, $question_id)
{
global $db, $cache;
// easier to delete all answers than to figure out which to update
$sql = 'DELETE FROM ' . CAPTCHA_ANSWERS_TABLE . " WHERE question_id = $question_id";
$db->sql_query($sql);
$langs = $this->get_languages();
$question_ary = $data;
$question_ary['lang_id'] = $langs[$question_ary['lang_iso']]['id'];
unset($question_ary['answers']);
$sql = 'UPDATE ' . CAPTCHA_QUESTIONS_TABLE . '
SET ' . $db->sql_build_array('UPDATE', $question_ary) . "
WHERE question_id = $question_id";
$db->sql_query($sql);
$this->acp_insert_answers($data, $question_id);
$cache->destroy('sql', CAPTCHA_QUESTIONS_TABLE);
}
/**
* Insert a question.
* param mixed $data : an array as created from acp_get_question_input or acp_get_question_data
*/
function acp_add_question($data)
{
global $db, $cache;
$langs = $this->get_languages();
$question_ary = $data;
$question_ary['lang_id'] = $langs[$data['lang_iso']]['id'];
unset($question_ary['answers']);
$sql = 'INSERT INTO ' . CAPTCHA_QUESTIONS_TABLE . ' ' . $db->sql_build_array('INSERT', $question_ary);
$db->sql_query($sql);
$question_id = $db->sql_nextid();
$this->acp_insert_answers($data, $question_id);
$cache->destroy('sql', CAPTCHA_QUESTIONS_TABLE);
}
/**
* Insert the answers.
* param mixed $data : an array as created from acp_get_question_input or acp_get_question_data
*/
function acp_insert_answers($data, $question_id)
{
global $db, $cache;
foreach ($data['answers'] as $answer)
{
$answer_ary = array(
'question_id' => $question_id,
'answer_text' => $answer,
);
$sql = 'INSERT INTO ' . CAPTCHA_ANSWERS_TABLE . ' ' . $db->sql_build_array('INSERT', $answer_ary);
$db->sql_query($sql);
}
$cache->destroy('sql', CAPTCHA_ANSWERS_TABLE);
}
/**
* Delete a question.
*/
function acp_delete_question($question_id)
{
global $db, $cache;
$tables = array(CAPTCHA_QUESTIONS_TABLE, CAPTCHA_ANSWERS_TABLE);
foreach ($tables as $table)
{
$sql = "DELETE FROM $table
WHERE question_id = $question_id";
$db->sql_query($sql);
}
$cache->destroy('sql', $tables);
}
/**
* Check if the entered data can be inserted/used
* param mixed $data : an array as created from acp_get_question_input or acp_get_question_data
*/
function validate_input($question_data)
{
$langs = $this->get_languages();
if (!isset($question_data['lang_iso']) ||
!isset($question_data['question_text']) ||
!isset($question_data['strict']) ||
!isset($question_data['answers']))
{
return false;
}
if (!isset($langs[$question_data['lang_iso']]) ||
!strlen($question_data['question_text']) ||
!sizeof($question_data['answers']) ||
!is_array($question_data['answers']))
{
return false;
}
return true;
}
/**
* List the installed language packs
*/
function get_languages()
{
global $db;
$sql = 'SELECT *
FROM ' . LANG_TABLE;
$result = $db->sql_query($sql);
$langs = array();
while ($row = $db->sql_fetchrow($result))
{
$langs[$row['lang_iso']] = array(
'name' => $row['lang_local_name'],
'id' => (int) $row['lang_id'],
);
}
$db->sql_freeresult($result);
return $langs;
}
/**
* See if there is a question other than the one we have
*/
function acp_is_last($question_id)
{
global $config, $db;
if ($question_id)
{
$sql = 'SELECT question_id
FROM ' . CAPTCHA_QUESTIONS_TABLE . "
WHERE lang_iso = '" . $db->sql_escape($config['default_lang']) . "'
AND question_id <> " . (int) $question_id;
$result = $db->sql_query_limit($sql, 1);
$question = $db->sql_fetchrow($result);
$db->sql_freeresult($result);
if (!$question)
{
return true;
}
return false;
}
}
}
?>