enrol/paypal/ipn.php

   1 <?php
   2 // This file is part of Moodle - http://moodle.org/
   3 //
   4 // Moodle is free software: you can redistribute it and/or modify
   5 // it under the terms of the GNU General Public License as published by
   6 // the Free Software Foundation, either version 3 of the License, or
   7 // (at your option) any later version.
   8 //
   9 // Moodle is distributed in the hope that it will be useful,
  10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 // GNU General Public License for more details.
  13 //
  14 // You should have received a copy of the GNU General Public License
  15 // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  16
  17 /**
  18  * Listens for Instant Payment Notification from PayPal
  19  *
  20  * This script waits for Payment notification from PayPal,
  21  * then double checks that data by sending it back to PayPal.
  22  * If PayPal verifies this then it sets up the enrolment for that
  23  * user.
  24  *
  25  * @package    enrol_paypal
  26  * @copyright 2010 Eugene Venter
  27  * @author     Eugene Venter - based on code by others
  28  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  29  */
  30
  31 // Disable moodle specific debug messages and any errors in output,
  32 // comment out when debugging or better look into error log!
  33 define('NO_DEBUG_DISPLAY', true);
  34
  35 // @codingStandardsIgnoreLine This script does not require login.
  36 require("../../config.php");
  37 require_once("lib.php");
  38 require_once($CFG->libdir.'/enrollib.php');
  39 require_once($CFG->libdir . '/filelib.php');
  40
  41 // PayPal does not like when we return error messages here,
  42 // the custom handler just logs exceptions and stops.
  43 set_exception_handler(\enrol_paypal\util::get_exception_handler());
  44
  45 // Make sure we are enabled in the first place.
  46 if (!enrol_is_enabled('paypal')) {
  47     http_response_code(503);
  48     throw new moodle_exception('errdisabled', 'enrol_paypal');
  49 }
  50
  51 /// Keep out casual intruders
  52 if (empty($_POST) or !empty($_GET)) {
  53     http_response_code(400);
  54     throw new moodle_exception('invalidrequest', 'core_error');
  55 }
  56
  57 /// Read all the data from PayPal and get it ready for later;
  58 /// we expect only valid UTF-8 encoding, it is the responsibility
  59 /// of user to set it up properly in PayPal business account,
  60 /// it is documented in docs wiki.
  61
  62 $req = 'cmd=_notify-validate';
  63
  64 $data = new stdClass();
  65
  66 foreach ($_POST as $key => $value) {
  67     if ($key !== clean_param($key, PARAM_ALPHANUMEXT)) {
  68         throw new moodle_exception('invalidrequest', 'core_error', '', null, $key);
  69     }
  70     if (is_array($value)) {
  71         throw new moodle_exception('invalidrequest', 'core_error', '', null, 'Unexpected array param: '.$key);
  72     }
  73     $req .= "&$key=".urlencode($value);
  74     $data->$key = fix_utf8($value);
  75 }
  76
  77 if (empty($data->custom)) {
  78     throw new moodle_exception('invalidrequest', 'core_error', '', null, 'Missing request param: custom');
  79 }
  80
  81 $custom = explode('-', $data->custom);
  82 unset($data->custom);
  83
  84 if (empty($custom) || count($custom) < 3) {
  85     throw new moodle_exception('invalidrequest', 'core_error', '', null, 'Invalid value of the request param: custom');
  86 }
  87
  88 $data->userid           = (int)$custom[0];
  89 $data->courseid         = (int)$custom[1];
  90 $data->instanceid       = (int)$custom[2];
  91 $data->payment_gross    = $data->mc_gross;
  92 $data->payment_currency = $data->mc_currency;
  93 $data->timeupdated      = time();
  94
  95 $user = $DB->get_record("user", array("id" => $data->userid), "*", MUST_EXIST);
  96 $course = $DB->get_record("course", array("id" => $data->courseid), "*", MUST_EXIST);
  97 $context = context_course::instance($course->id, MUST_EXIST);
  98
  99 $PAGE->set_context($context);
 100
 101 $plugin_instance = $DB->get_record("enrol", array("id" => $data->instanceid, "enrol" => "paypal", "status" => 0), "*", MUST_EXIST);
 102 $plugin = enrol_get_plugin('paypal');
 103
 104 /// Open a connection back to PayPal to validate the data
 105 $paypaladdr = empty($CFG->usepaypalsandbox) ? 'ipnpb.paypal.com' : 'ipnpb.sandbox.paypal.com';
 106 $c = new curl();
 107 $options = array(
 108     'returntransfer' => true,
 109     'httpheader' => array('application/x-www-form-urlencoded', "Host: $paypaladdr"),
 110     'timeout' => 30,
 111     'CURLOPT_HTTP_VERSION' => CURL_HTTP_VERSION_1_1,
 112 );
 113 $location = "https://$paypaladdr/cgi-bin/webscr";
 114 $result = $c->post($location, $req, $options);
 115
 116 if ($c->get_errno()) {
 117     throw new moodle_exception('errpaypalconnect', 'enrol_paypal', '', array('url' => $paypaladdr, 'result' => $result),
 118         json_encode($data));
 119 }
 120
 121 /// Connection is OK, so now we post the data to validate it
 122
 123 /// Now read the response and check if everything is OK.
 124
 125 if (strlen($result) > 0) {
 126     if (strcmp($result, "VERIFIED") == 0) {          // VALID PAYMENT!
 127
 128
 129         // check the payment_status and payment_reason
 130
 131         // If status is not completed or pending then unenrol the student if already enrolled
 132         // and notify admin
 133
 134         if ($data->payment_status != "Completed" and $data->payment_status != "Pending") {
 135             $plugin->unenrol_user($plugin_instance, $data->userid);
 136             \enrol_paypal\util::message_paypal_error_to_admin("Status not completed or pending. User unenrolled from course",
 137                                                               $data);
 138             die;
 139         }
 140
 141         // If currency is incorrectly set then someone maybe trying to cheat the system
 142
 143         if ($data->mc_currency != $plugin_instance->currency) {
 144             \enrol_paypal\util::message_paypal_error_to_admin(
 145                 "Currency does not match course settings, received: ".$data->mc_currency,
 146                 $data);
 147             die;
 148         }
 149
 150         // If status is pending and reason is other than echeck then we are on hold until further notice
 151         // Email user to let them know. Email admin.
 152
 153         if ($data->payment_status == "Pending" and $data->pending_reason != "echeck") {
 154             $eventdata = new \core\message\message();
 155             $eventdata->courseid          = empty($data->courseid) ? SITEID : $data->courseid;
 156             $eventdata->modulename        = 'moodle';
 157             $eventdata->component         = 'enrol_paypal';
 158             $eventdata->name              = 'paypal_enrolment';
 159             $eventdata->userfrom          = get_admin();
 160             $eventdata->userto            = $user;
 161             $eventdata->subject           = "Moodle: PayPal payment";
 162             $eventdata->fullmessage       = "Your PayPal payment is pending.";
 163             $eventdata->fullmessageformat = FORMAT_PLAIN;
 164             $eventdata->fullmessagehtml   = '';
 165             $eventdata->smallmessage      = '';
 166             message_send($eventdata);
 167
 168             \enrol_paypal\util::message_paypal_error_to_admin("Payment pending", $data);
 169             die;
 170         }
 171
 172         // If our status is not completed or not pending on an echeck clearance then ignore and die
 173         // This check is redundant at present but may be useful if paypal extend the return codes in the future
 174
 175         if (! ( $data->payment_status == "Completed" or
 176                ($data->payment_status == "Pending" and $data->pending_reason == "echeck") ) ) {
 177             die;
 178         }
 179
 180         // At this point we only proceed with a status of completed or pending with a reason of echeck
 181
 182         // Make sure this transaction doesn't exist already.
 183         if ($existing = $DB->get_record("enrol_paypal", array("txn_id" => $data->txn_id), "*", IGNORE_MULTIPLE)) {
 184             \enrol_paypal\util::message_paypal_error_to_admin("Transaction $data->txn_id is being repeated!", $data);
 185             die;
 186         }
 187
 188         // Check that the receiver email is the one we want it to be.
 189         if (isset($data->business)) {
 190             $recipient = $data->business;
 191         } else if (isset($data->receiver_email)) {
 192             $recipient = $data->receiver_email;
 193         } else {
 194             $recipient = 'empty';
 195         }
 196
 197         if (core_text::strtolower($recipient) !== core_text::strtolower($plugin->get_config('paypalbusiness'))) {
 198             \enrol_paypal\util::message_paypal_error_to_admin("Business email is {$recipient} (not ".
 199                     $plugin->get_config('paypalbusiness').")", $data);
 200             die;
 201         }
 202
 203         if (!$user = $DB->get_record('user', array('id'=>$data->userid))) {   // Check that user exists
 204             \enrol_paypal\util::message_paypal_error_to_admin("User $data->userid doesn't exist", $data);
 205             die;
 206         }
 207
 208         if (!$course = $DB->get_record('course', array('id'=>$data->courseid))) { // Check that course exists
 209             \enrol_paypal\util::message_paypal_error_to_admin("Course $data->courseid doesn't exist", $data);
 210             die;
 211         }
 212
 213         $coursecontext = context_course::instance($course->id, IGNORE_MISSING);
 214
 215         // Check that amount paid is the correct amount
 216         if ( (float) $plugin_instance->cost <= 0 ) {
 217             $cost = (float) $plugin->get_config('cost');
 218         } else {
 219             $cost = (float) $plugin_instance->cost;
 220         }
 221
 222         // Use the same rounding of floats as on the enrol form.
 223         $cost = format_float($cost, 2, false);
 224
 225         if ($data->payment_gross < $cost) {
 226             \enrol_paypal\util::message_paypal_error_to_admin("Amount paid is not enough ($data->payment_gross < $cost))", $data);
 227             die;
 228
 229         }
 230         // Use the queried course's full name for the item_name field.
 231         $data->item_name = $course->fullname;
 232
 233         // ALL CLEAR !
 234
 235         $DB->insert_record("enrol_paypal", $data);
 236
 237         if ($plugin_instance->enrolperiod) {
 238             $timestart = time();
 239             $timeend   = $timestart + $plugin_instance->enrolperiod;
 240         } else {
 241             $timestart = 0;
 242             $timeend   = 0;
 243         }
 244
 245         // Enrol user
 246         $plugin->enrol_user($plugin_instance, $user->id, $plugin_instance->roleid, $timestart, $timeend);
 247
 248         // Pass $view=true to filter hidden caps if the user cannot see them
 249         if ($users = get_users_by_capability($context, 'moodle/course:update', 'u.*', 'u.id ASC',
 250                                              '', '', '', '', false, true)) {
 251             $users = sort_by_roleassignment_authority($users, $context);
 252             $teacher = array_shift($users);
 253         } else {
 254             $teacher = false;
 255         }
 256
 257         $mailstudents = $plugin->get_config('mailstudents');
 258         $mailteachers = $plugin->get_config('mailteachers');
 259         $mailadmins   = $plugin->get_config('mailadmins');
 260         $shortname = format_string($course->shortname, true, array('context' => $context));
 261
 262
 263         if (!empty($mailstudents)) {
 264             $a = new stdClass();
 265             $a->coursename = format_string($course->fullname, true, array('context' => $coursecontext));
 266             $a->profileurl = "$CFG->wwwroot/user/view.php?id=$user->id";
 267
 268             $eventdata = new \core\message\message();
 269             $eventdata->courseid          = $course->id;
 270             $eventdata->modulename        = 'moodle';
 271             $eventdata->component         = 'enrol_paypal';
 272             $eventdata->name              = 'paypal_enrolment';
 273             $eventdata->userfrom          = empty($teacher) ? core_user::get_noreply_user() : $teacher;
 274             $eventdata->userto            = $user;
 275             $eventdata->subject           = get_string("enrolmentnew", 'enrol', $shortname);
 276             $eventdata->fullmessage       = get_string('welcometocoursetext', '', $a);
 277             $eventdata->fullmessageformat = FORMAT_PLAIN;
 278             $eventdata->fullmessagehtml   = '';
 279             $eventdata->smallmessage      = '';
 280             message_send($eventdata);
 281
 282         }
 283
 284         if (!empty($mailteachers) && !empty($teacher)) {
 285             $a->course = format_string($course->fullname, true, array('context' => $coursecontext));
 286             $a->user = fullname($user);
 287
 288             $eventdata = new \core\message\message();
 289             $eventdata->courseid          = $course->id;
 290             $eventdata->modulename        = 'moodle';
 291             $eventdata->component         = 'enrol_paypal';
 292             $eventdata->name              = 'paypal_enrolment';
 293             $eventdata->userfrom          = $user;
 294             $eventdata->userto            = $teacher;
 295             $eventdata->subject           = get_string("enrolmentnew", 'enrol', $shortname);
 296             $eventdata->fullmessage       = get_string('enrolmentnewuser', 'enrol', $a);
 297             $eventdata->fullmessageformat = FORMAT_PLAIN;
 298             $eventdata->fullmessagehtml   = '';
 299             $eventdata->smallmessage      = '';
 300             message_send($eventdata);
 301         }
 302
 303         if (!empty($mailadmins)) {
 304             $a->course = format_string($course->fullname, true, array('context' => $coursecontext));
 305             $a->user = fullname($user);
 306             $admins = get_admins();
 307             foreach ($admins as $admin) {
 308                 $eventdata = new \core\message\message();
 309                 $eventdata->courseid          = $course->id;
 310                 $eventdata->modulename        = 'moodle';
 311                 $eventdata->component         = 'enrol_paypal';
 312                 $eventdata->name              = 'paypal_enrolment';
 313                 $eventdata->userfrom          = $user;
 314                 $eventdata->userto            = $admin;
 315                 $eventdata->subject           = get_string("enrolmentnew", 'enrol', $shortname);
 316                 $eventdata->fullmessage       = get_string('enrolmentnewuser', 'enrol', $a);
 317                 $eventdata->fullmessageformat = FORMAT_PLAIN;
 318                 $eventdata->fullmessagehtml   = '';
 319                 $eventdata->smallmessage      = '';
 320                 message_send($eventdata);
 321             }
 322         }
 323
 324     } else if (strcmp ($result, "INVALID") == 0) { // ERROR
 325         $DB->insert_record("enrol_paypal", $data, false);
 326         throw new moodle_exception('erripninvalid', 'enrol_paypal', '', null, json_encode($data));
 327     }
 328 }