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
  26  * @subpackage paypal
  27  * @copyright 2010 Eugene Venter
  28  * @author     Eugene Venter - based on code by others
  29  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  30  */
  31
  32
  33 require("../../config.php");
  34 require_once("lib.php");
  35 require_once($CFG->libdir.'/eventslib.php');
  36 require_once($CFG->libdir.'/enrollib.php');
  37
  38
  39 /// Keep out casual intruders
  40 if (empty($_POST) or !empty($_GET)) {
  41     print_error("Sorry, you can not use the script that way.");
  42 }
  43
  44 /// Read all the data from PayPal and get it ready for later;
  45 /// we expect only valid UTF-8 encoding, it is the responsibility
  46 /// of user to set it up properly in PayPal business account,
  47 /// it is documented in docs wiki.
  48
  49 $req = 'cmd=_notify-validate';
  50
  51 $data = new stdClass();
  52
  53 foreach ($_POST as $key => $value) {
  54     $req .= "&$key=".urlencode($value);
  55     $data->$key = $value;
  56 }
  57
  58 $custom = explode('-', $data->custom);
  59 $data->userid           = (int)$custom[0];
  60 $data->courseid         = (int)$custom[1];
  61 $data->instanceid       = (int)$custom[2];
  62 $data->payment_gross    = $data->mc_gross;
  63 $data->payment_currency = $data->mc_currency;
  64 $data->timeupdated      = time();
  65
  66
  67 /// get the user and course records
  68
  69 if (! $user = $DB->get_record("user", array("id"=>$data->userid))) {
  70     message_paypal_error_to_admin("Not a valid user id", $data);
  71     die;
  72 }
  73
  74 if (! $course = $DB->get_record("course", array("id"=>$data->courseid))) {
  75     message_paypal_error_to_admin("Not a valid course id", $data);
  76     die;
  77 }
  78
  79 if (! $context = get_context_instance(CONTEXT_COURSE, $course->id)) {
  80     message_paypal_error_to_admin("Not a valid context id", $data);
  81     die;
  82 }
  83
  84 if (! $plugin_instance = $DB->get_record("enrol", array("id"=>$data->instanceid, "status"=>0))) {
  85     message_paypal_error_to_admin("Not a valid instance id", $data);
  86     die;
  87 }
  88
  89 $plugin = enrol_get_plugin('paypal');
  90
  91 /// Open a connection back to PayPal to validate the data
  92 $header = '';
  93 $header .= "POST /cgi-bin/webscr HTTP/1.0\r\n";
  94 $header .= "Content-Type: application/x-www-form-urlencoded\r\n";
  95 $header .= "Content-Length: " . strlen($req) . "\r\n\r\n";
  96 $paypaladdr = empty($CFG->usepaypalsandbox) ? 'www.paypal.com' : 'www.sandbox.paypal.com';
  97 $fp = fsockopen ($paypaladdr, 80, $errno, $errstr, 30);
  98
  99 if (!$fp) {  /// Could not open a socket to PayPal - FAIL
 100     echo "<p>Error: could not access paypal.com</p>";
 101     message_paypal_error_to_admin("Could not access paypal.com to verify payment", $data);
 102     die;
 103 }
 104
 105 /// Connection is OK, so now we post the data to validate it
 106
 107 fputs ($fp, $header.$req);
 108
 109 /// Now read the response and check if everything is OK.
 110
 111 while (!feof($fp)) {
 112     $result = fgets($fp, 1024);
 113     if (strcmp($result, "VERIFIED") == 0) {          // VALID PAYMENT!
 114
 115
 116         // check the payment_status and payment_reason
 117
 118         // If status is not completed or pending then unenrol the student if already enrolled
 119         // and notify admin
 120
 121         if ($data->payment_status != "Completed" and $data->payment_status != "Pending") {
 122             $plugin->unenrol_user($plugin_instance, $data->userid);
 123             message_paypal_error_to_admin("Status not completed or pending. User unenrolled from course", $data);
 124             die;
 125         }
 126
 127         // If currency is incorrectly set then someone maybe trying to cheat the system
 128
 129         if ($data->mc_currency != $plugin_instance->currency) {
 130             message_paypal_error_to_admin("Currency does not match course settings, received: ".$data->mc_currency, $data);
 131             die;
 132         }
 133
 134         // If status is pending and reason is other than echeck then we are on hold until further notice
 135         // Email user to let them know. Email admin.
 136
 137         if ($data->payment_status == "Pending" and $data->pending_reason != "echeck") {
 138             $eventdata = new stdClass();
 139             $eventdata->modulename        = 'moodle';
 140             $eventdata->component         = 'enrol_paypal';
 141             $eventdata->name              = 'paypal_enrolment';
 142             $eventdata->userfrom          = get_admin();
 143             $eventdata->userto            = $user;
 144             $eventdata->subject           = "Moodle: PayPal payment";
 145             $eventdata->fullmessage       = "Your PayPal payment is pending.";
 146             $eventdata->fullmessageformat = FORMAT_PLAIN;
 147             $eventdata->fullmessagehtml   = '';
 148             $eventdata->smallmessage      = '';
 149             message_send($eventdata);
 150
 151             message_paypal_error_to_admin("Payment pending", $data);
 152             die;
 153         }
 154
 155         // If our status is not completed or not pending on an echeck clearance then ignore and die
 156         // This check is redundant at present but may be useful if paypal extend the return codes in the future
 157
 158         if (! ( $data->payment_status == "Completed" or
 159                ($data->payment_status == "Pending" and $data->pending_reason == "echeck") ) ) {
 160             die;
 161         }
 162
 163         // At this point we only proceed with a status of completed or pending with a reason of echeck
 164
 165
 166
 167         if ($existing = $DB->get_record("enrol_paypal", array("txn_id"=>$data->txn_id))) {   // Make sure this transaction doesn't exist already
 168             message_paypal_error_to_admin("Transaction $data->txn_id is being repeated!", $data);
 169             die;
 170
 171         }
 172
 173         if ($data->business != $plugin->get_config('paypalbusiness')) {   // Check that the email is the one we want it to be
 174             message_paypal_error_to_admin("Business email is {$data->business} (not ".
 175                     $plugin->get_config('paypalbusiness').")", $data);
 176             die;
 177
 178         }
 179
 180         if (!$user = $DB->get_record('user', array('id'=>$data->userid))) {   // Check that user exists
 181             message_paypal_error_to_admin("User $data->userid doesn't exist", $data);
 182             die;
 183         }
 184
 185         if (!$course = $DB->get_record('course', array('id'=>$data->courseid))) { // Check that course exists
 186             message_paypal_error_to_admin("Course $data->courseid doesn't exist", $data);;
 187             die;
 188         }
 189
 190         $coursecontext = get_context_instance(CONTEXT_COURSE, $course->id);
 191
 192         // Check that amount paid is the correct amount
 193         if ( (float) $plugin_instance->cost <= 0 ) {
 194             $cost = (float) $plugin->get_config('cost');
 195         } else {
 196             $cost = (float) $plugin_instance->cost;
 197         }
 198
 199         if ($data->payment_gross < $cost) {
 200             $cost = format_float($cost, 2);
 201             message_paypal_error_to_admin("Amount paid is not enough ($data->payment_gross < $cost))", $data);
 202             die;
 203
 204         }
 205
 206         // ALL CLEAR !
 207
 208         $DB->insert_record("enrol_paypal", $data);
 209
 210         if ($plugin_instance->enrolperiod) {
 211             $timestart = time();
 212             $timeend   = $timestart + $plugin_instance->enrolperiod;
 213         } else {
 214             $timestart = 0;
 215             $timeend   = 0;
 216         }
 217
 218         // Enrol user
 219         $plugin->enrol_user($plugin_instance, $user->id, $plugin_instance->roleid, $timestart, $timeend);
 220
 221         // Pass $view=true to filter hidden caps if the user cannot see them
 222         if ($users = get_users_by_capability($context, 'moodle/course:update', 'u.*', 'u.id ASC',
 223                                              '', '', '', '', false, true)) {
 224             $users = sort_by_roleassignment_authority($users, $context);
 225             $teacher = array_shift($users);
 226         } else {
 227             $teacher = false;
 228         }
 229
 230         $mailstudents = $plugin->get_config('mailstudents');
 231         $mailteachers = $plugin->get_config('mailteachers');
 232         $mailadmins   = $plugin->get_config('mailadmins');
 233         $shortname = format_string($course->shortname, true, array('context' => $context));
 234
 235
 236         if (!empty($mailstudents)) {
 237             $a->coursename = format_string($course->fullname, true, array('context' => $coursecontext));
 238             $a->profileurl = "$CFG->wwwroot/user/view.php?id=$user->id";
 239
 240             $eventdata = new stdClass();
 241             $eventdata->modulename        = 'moodle';
 242             $eventdata->component         = 'enrol_paypal';
 243             $eventdata->name              = 'paypal_enrolment';
 244             $eventdata->userfrom          = $teacher;
 245             $eventdata->userto            = $user;
 246             $eventdata->subject           = get_string("enrolmentnew", 'enrol', $shortname);
 247             $eventdata->fullmessage       = get_string('welcometocoursetext', '', $a);
 248             $eventdata->fullmessageformat = FORMAT_PLAIN;
 249             $eventdata->fullmessagehtml   = '';
 250             $eventdata->smallmessage      = '';
 251             message_send($eventdata);
 252
 253         }
 254
 255         if (!empty($mailteachers)) {
 256             $a->course = format_string($course->fullname, true, array('context' => $coursecontext));
 257             $a->user = fullname($user);
 258
 259             $eventdata = new stdClass();
 260             $eventdata->modulename        = 'moodle';
 261             $eventdata->component         = 'enrol_paypal';
 262             $eventdata->name              = 'paypal_enrolment';
 263             $eventdata->userfrom          = $user;
 264             $eventdata->userto            = $teacher;
 265             $eventdata->subject           = get_string("enrolmentnew", 'enrol', $shortname);
 266             $eventdata->fullmessage       = get_string('enrolmentnewuser', 'enrol', $a);
 267             $eventdata->fullmessageformat = FORMAT_PLAIN;
 268             $eventdata->fullmessagehtml   = '';
 269             $eventdata->smallmessage      = '';
 270             message_send($eventdata);
 271         }
 272
 273         if (!empty($mailadmins)) {
 274             $a->course = format_string($course->fullname, true, array('context' => $coursecontext));
 275             $a->user = fullname($user);
 276             $admins = get_admins();
 277             foreach ($admins as $admin) {
 278                 $eventdata = new stdClass();
 279                 $eventdata->modulename        = 'moodle';
 280                 $eventdata->component         = 'enrol_paypal';
 281                 $eventdata->name              = 'paypal_enrolment';
 282                 $eventdata->userfrom          = $user;
 283                 $eventdata->userto            = $admin;
 284                 $eventdata->subject           = get_string("enrolmentnew", 'enrol', $shortname);
 285                 $eventdata->fullmessage       = get_string('enrolmentnewuser', 'enrol', $a);
 286                 $eventdata->fullmessageformat = FORMAT_PLAIN;
 287                 $eventdata->fullmessagehtml   = '';
 288                 $eventdata->smallmessage      = '';
 289                 message_send($eventdata);
 290             }
 291         }
 292
 293     } else if (strcmp ($result, "INVALID") == 0) { // ERROR
 294         $DB->insert_record("enrol_paypal", $data, false);
 295         message_paypal_error_to_admin("Received an invalid payment notification!! (Fake payment?)", $data);
 296     }
 297 }
 298
 299 fclose($fp);
 300 exit;
 301
 302
 303 //--- HELPER FUNCTIONS --------------------------------------------------------------------------------------
 304
 305
 306 function message_paypal_error_to_admin($subject, $data) {
 307     echo $subject;
 308     $admin = get_admin();
 309     $site = get_site();
 310
 311     $message = "$site->fullname:  Transaction failed.\n\n$subject\n\n";
 312
 313     foreach ($data as $key => $value) {
 314         $message .= "$key => $value\n";
 315     }
 316
 317     $eventdata = new stdClass();
 318     $eventdata->modulename        = 'moodle';
 319     $eventdata->component         = 'enrol_paypal';
 320     $eventdata->name              = 'paypal_enrolment';
 321     $eventdata->userfrom          = $admin;
 322     $eventdata->userto            = $admin;
 323     $eventdata->subject           = "PAYPAL ERROR: ".$subject;
 324     $eventdata->fullmessage       = $message;
 325     $eventdata->fullmessageformat = FORMAT_PLAIN;
 326     $eventdata->fullmessagehtml   = '';
 327     $eventdata->smallmessage      = '';
 328     message_send($eventdata);
 329 }
 330
 331