jappixmini/jappixmini.php

   1 <?php
   2
   3
   4 /**
   5 * Name: jappixmini
   6 * Description: Inserts a jabber chat
   7 * Version: 1.0
   8 * Author: leberwurscht
   9 *
  10 */
  11
  12 /*
  13
  14 Problem:
  15 * jabber password should not be stored on server
  16 * jabber password should not be sent between server and browser as soon as the user is logged in
  17 * jabber password should not be reconstructible from communication between server and browser as soon as the user is logged in
  18
  19 Solution:
  20 Only store an encrypted version of the jabber password on the server. The encryption key is only available to the browser
  21 and not to the server (at least as soon as the user is logged in). It can be stored using the jappix setDB function.
  22
  23 This encryption key could be the friendica password, but then this password would be stored in the browser in cleartext.
  24 It is better to use a hash of the password.
  25 The server should not be able to reconstruct the password, so we can't take the same hash the server stores. But we can
  26  use hash("some_prefix"+password). This will however not work with OpenID logins, for this type of login the password must
  27 be queried manually.
  28
  29 Problem:
  30 How to discover the jabber addresses of the friendica contacts?
  31
  32 Solution:
  33 Each Friendica site with this addon provides a /jappixmini/ module page. We go through our contacts and retrieve
  34 this information every week using a cron hook.
  35
  36 Problem:
  37 We do not want to make the jabber address public.
  38
  39 Solution:
  40 When two friendica users connect using DFRN, the relation gets a DFRN ID and a keypair is generated.
  41 Using this keypair, we can provide the jabber address only to contacts:
  42
  43 Alice:
  44   signed_address = openssl_*_encrypt(alice_jabber_address)
  45 send signed_address to Bob, who does
  46   trusted_address = openssl_*_decrypt(signed_address)
  47   save trusted_address
  48   encrypted_address = openssl_*_encrypt(bob_jabber_address)
  49 reply with encrypted_address to Alice, who does
  50   decrypted_address = openssl_*_decrypt(encrypted_address)
  51   save decrypted_address
  52
  53 Interface for this:
  54 GET /jappixmini/?role=%s&signed_address=%s&dfrn_id=%s
  55
  56 Response:
  57 json({"status":"ok", "encrypted_address":"%s"})
  58
  59 */
  60
  61 function jappixmini_install() {
  62 register_hook('plugin_settings', 'addon/jappixmini/jappixmini.php', 'jappixmini_settings');
  63 register_hook('plugin_settings_post', 'addon/jappixmini/jappixmini.php', 'jappixmini_settings_post');
  64
  65 register_hook('page_end', 'addon/jappixmini/jappixmini.php', 'jappixmini_script');
  66 register_hook('authenticate', 'addon/jappixmini/jappixmini.php', 'jappixmini_login');
  67
  68 register_hook('cron', 'addon/jappixmini/jappixmini.php', 'jappixmini_cron');
  69
  70 // Jappix source download as required by AGPL
  71 register_hook('about_hook', 'addon/jappixmini/jappixmini.php', 'jappixmini_download_source');
  72 }
  73
  74
  75 function jappixmini_uninstall() {
  76 unregister_hook('plugin_settings', 'addon/jappixmini/jappixmini.php', 'jappixmini_settings');
  77 unregister_hook('plugin_settings_post', 'addon/jappixmini/jappixmini.php', 'jappixmini_settings_post');
  78
  79 unregister_hook('page_end', 'addon/jappixmini/jappixmini.php', 'jappixmini_script');
  80 unregister_hook('authenticate', 'addon/jappixmini/jappixmini.php', 'jappixmini_login');
  81
  82 unregister_hook('cron', 'addon/jappixmini/jappixmini.php', 'jappixmini_cron');
  83
  84 unregister_hook('about_hook', 'addon/jappixmini/jappixmini.php', 'jappixmini_download_source');
  85 }
  86
  87 function jappixmini_plugin_admin(&$a, &$o) {
  88         // display instructions and warnings on addon settings page for admin
  89
  90         if (!file_exists("addon/jappixmini/jappix")) {
  91                 $o .= '<p><strong>You need to install the Jappix application, adapted for Friendica (see README).</strong></p>';
  92         }
  93         else if (!file_exists("addon/jappixmini/jappix.zip")) {
  94                 $o .= '<p><strong style="color:#fff;background-color:#f00">The source archive jappix.zip does not exist. This is probably a violation of the Jappix License (see README).</strong></p>';
  95         }
  96         else {
  97                 $o .= '<p>Jappix is installed.</p>';
  98         }
  99 }
 100
 101 function jappixmini_plugin_admin_post(&$a) {
 102 }
 103
 104 function jappixmini_module() {}
 105 function jappixmini_init(&$a) {
 106         // module page where other Friendica sites can submit Jabber addresses to and also can query Jabber addresses
 107         // of local users
 108
 109         if (!file_exists("addon/jappixmini/jappix")) killme();
 110
 111         $dfrn_id = $_REQUEST["dfrn_id"];
 112         if (!$dfrn_id) killme();
 113
 114         $role = $_REQUEST["role"];
 115         if ($role=="pub") {
 116                 $r = q("SELECT * FROM `contact` WHERE LENGTH(`pubkey`) AND `dfrn-id`='%s' LIMIT 1",
 117                         dbesc($dfrn_id)
 118                 );
 119                 if (!count($r)) killme();
 120
 121                 $encrypt_func = openssl_public_encrypt;
 122                 $decrypt_func = openssl_public_decrypt;
 123                 $key = $r[0]["pubkey"];
 124         } else if ($role=="prv") {
 125                 $r = q("SELECT * FROM `contact` WHERE LENGTH(`prvkey`) AND `issued-id`='%s' LIMIT 1",
 126                         dbesc($dfrn_id)
 127                 );
 128                 if (!count($r)) killme();
 129
 130                 $encrypt_func = openssl_private_encrypt;
 131                 $decrypt_func = openssl_private_decrypt;
 132                 $key = $r[0]["prvkey"];
 133         } else {
 134                 killme();
 135         }
 136
 137         $uid = $r[0]["uid"];
 138
 139         // save the Jabber address we received
 140         try {
 141                 $signed_address_hex = $_REQUEST["signed_address"];
 142                 $signed_address = hex2bin($signed_address_hex);
 143
 144                 $trusted_address = "";
 145                 $decrypt_func($signed_address, $trusted_address, $key);
 146
 147                 $now = intval(time());
 148                 set_pconfig($uid, "jappixmini", "id:$dfrn_id", "$now:$trusted_address");
 149         } catch (Exception $e) {
 150         }
 151
 152         // do not return an address if user deactivated plugin
 153         $activated = get_pconfig($uid, 'jappixmini', 'activate');
 154         if (!$activated) killme();
 155
 156         // return the requested Jabber address
 157         try {
 158                 $username = get_pconfig($uid, 'jappixmini', 'username');
 159                 $server = get_pconfig($uid, 'jappixmini', 'server');
 160                 $address = "$username@$server";
 161
 162                 $encrypted_address = "";
 163                 $encrypt_func($address, $encrypted_address, $key);
 164
 165                 $encrypted_address_hex = bin2hex($encrypted_address);
 166
 167                 $answer = Array(
 168                         "status"=>"ok",
 169                         "encrypted_address"=>$encrypted_address_hex
 170                 );
 171
 172                 $answer_json = json_encode($answer);
 173                 echo $answer_json;
 174                 killme();
 175         } catch (Exception $e) {
 176                 killme();
 177         }
 178 }
 179
 180 function jappixmini_settings(&$a, &$s) {
 181     // addon settings for a user
 182
 183     if (!file_exists("addon/jappixmini/jappix")) return;
 184
 185     $activate = get_pconfig(local_user(),'jappixmini','activate');
 186     $activate = intval($activate) ? ' checked="checked"' : '';
 187
 188     $username = get_pconfig(local_user(),'jappixmini','username');
 189     $username = htmlentities($username);
 190     $server = get_pconfig(local_user(),'jappixmini','server');
 191     $server = htmlentities($server);
 192     $bosh = get_pconfig(local_user(),'jappixmini','bosh');
 193     $bosh = htmlentities($bosh);
 194     $password = get_pconfig(local_user(),'jappixmini','password');
 195     $autosubscribe = get_pconfig(local_user(),'jappixmini','autosubscribe');
 196     $autosubscribe = intval($autosubscribe) ? ' checked="checked"' : '';
 197     $autoapprove = get_pconfig(local_user(),'jappixmini','autoapprove');
 198     $autoapprove = intval($autoapprove) ? ' checked="checked"' : '';
 199     $encrypt = intval(get_pconfig(local_user(),'jappixmini','encrypt'));
 200     $encrypt_checked = $encrypt ? ' checked="checked"' : '';
 201     $encrypt_disabled = $encrypt ? '' : ' disabled="disabled"';
 202
 203     if (!$activate) {
 204         // load scripts if not yet activated so that password can be saved
 205         $a->page['htmlhead'] .= '<script type="text/javascript" src="' . $a->get_baseurl() . '/addon/jappixmini/jappix/php/get.php?t=js&amp;g=mini.xml"></script>'."\r\n";
 206         $a->page['htmlhead'] .= '<script type="text/javascript" src="' . $a->get_baseurl() . '/addon/jappixmini/jappix/php/get.php?t=js&amp;f=presence.js"></script>'."\r\n";
 207
 208         $a->page['htmlhead'] .= '<script type="text/javascript" src="' . $a->get_baseurl() . '/addon/jappixmini/jappix/php/get.php?t=js&amp;f=caps.js"></script>'."\r\n";
 209         $a->page['htmlhead'] .= '<script type="text/javascript" src="' . $a->get_baseurl() . '/addon/jappixmini/jappix/php/get.php?t=js&amp;f=name.js"></script>'."\r\n";
 210         $a->page['htmlhead'] .= '<script type="text/javascript" src="' . $a->get_baseurl() . '/addon/jappixmini/jappix/php/get.php?t=js&amp;f=roster.js"></script>'."\r\n";
 211
 212         $a->page['htmlhead'] .= '<script type="text/javascript" src="' . $a->get_baseurl() . '/addon/jappixmini/lib.js"></script>'."\r\n";
 213     }
 214
 215     $s .= '<div class="settings-block">';
 216
 217     $s .= '<h3>Jappix Mini addon settings</h3>';
 218     $s .= '<div>';
 219     $s .= '<label for="jappixmini-activate">Activate addon</label>';
 220     $s .= ' <input id="jappixmini-activate" type="checkbox" name="jappixmini-activate" value="1"'.$activate.' />';
 221     $s .= '<br />';
 222     $s .= '<label for="jappixmini-username">Jabber username</label>';
 223     $s .= ' <input id="jappixmini-username" type="text" name="jappixmini-username" value="'.$username.'" />';
 224     $s .= '<br />';
 225     $s .= '<label for="jappixmini-server">Jabber server</label>';
 226     $s .= ' <input id="jappixmini-server" type="text" name="jappixmini-server" value="'.$server.'" />';
 227     $s .= '<br />';
 228
 229     $conf = file_get_contents("addon/jappixmini/jappix/store/conf/main.xml");
 230     preg_match("/<bosh_proxy>(.*)<\/bosh_proxy>/", $conf, $matches);
 231     if ($matches[1]=="on") {
 232         $s .= '<label for="jappixmini-bosh">Jabber BOSH host</label>';
 233         $s .= ' <input id="jappixmini-bosh" type="text" name="jappixmini-bosh" value="'.$bosh.'" />';
 234         $s .= '<br />';
 235     }
 236
 237     $s .= '<label for="jappixmini-password">Jabber password</label>';
 238     $s .= ' <input type="hidden" id="jappixmini-password" name="jappixmini-encrypted-password" value="'.$password.'" />';
 239     $s .= ' <input id="jappixmini-clear-password" type="password" value="" onchange="jappixmini_set_password();" />';
 240     $s .= '<br />';
 241     $onchange = "document.getElementById('jappixmini-friendica-password').disabled = !this.checked;jappixmini_set_password();";
 242     $s .= '<label for="jappixmini-encrypt">Encrypt Jabber password with Friendica password (recommended)</label>';
 243     $s .= ' <input id="jappixmini-encrypt" type="checkbox" name="jappixmini-encrypt" onchange="'.$onchange.'" value="1"'.$encrypt_checked.' />';
 244     $s .= '<br />';
 245     $s .= '<label for="jappixmini-friendica-password">Friendica password</label>';
 246     $s .= ' <input id="jappixmini-friendica-password" name="jappixmini-friendica-password" type="password" onchange="jappixmini_set_password();" value=""'.$encrypt_disabled.' />';
 247     $s .= '<br />';
 248     $s .= '<label for="jappixmini-autoapprove">Approve subscription requests from Friendica contacts automatically</label>';
 249     $s .= ' <input id="jappixmini-autoapprove" type="checkbox" name="jappixmini-autoapprove" value="1"'.$autoapprove.' />';
 250     $s .= '<br />';
 251     $s .= '<label for="jappixmini-autosubscribe">Subscribe to Friendica contacts automatically</label>';
 252     $s .= ' <input id="jappixmini-autosubscribe" type="checkbox" name="jappixmini-autosubscribe" value="1"'.$autosubscribe.' />';
 253     $s .= '<br />';
 254     $s .= '<label for="jappixmini-purge">Purge internal list of jabber addresses of contacts</label>';
 255     $s .= ' <input id="jappixmini-purge" type="checkbox" name="jappixmini-purge" value="1" />';
 256     $s .= '<br />';
 257     $s .= '<input type="submit" name="jappixmini-submit" value="' . t('Submit') . '" />';
 258     $s .= ' <input type="button" value="Add contact" onclick="jappixmini_addon_subscribe();" />';
 259     $s .= '</div>';
 260
 261     $s .= '</div>';
 262
 263     $a->page['htmlhead'] .= "<script type=\"text/javascript\">
 264         function jappixmini_set_password() {
 265             encrypt = document.getElementById('jappixmini-encrypt').checked;
 266             password = document.getElementById('jappixmini-password');
 267             clear_password = document.getElementById('jappixmini-clear-password');
 268             if (encrypt) {
 269                 friendica_password = document.getElementById('jappixmini-friendica-password');
 270
 271                 if (friendica_password) {
 272                     jappixmini_addon_set_client_secret(friendica_password.value);
 273                     jappixmini_addon_encrypt_password(clear_password.value, function(encrypted_password){
 274                         password.value = encrypted_password;
 275                     });
 276                 }
 277             }
 278             else {
 279                 password.value = clear_password.value;
 280             }
 281         }
 282
 283         jQuery(document).ready(function() {
 284             encrypt = document.getElementById('jappixmini-encrypt').checked;
 285             password = document.getElementById('jappixmini-password');
 286             clear_password = document.getElementById('jappixmini-clear-password');
 287             if (encrypt) {
 288                 jappixmini_addon_decrypt_password(password.value, function(decrypted_password){
 289                     clear_password.value = decrypted_password;
 290                 });
 291             }
 292             else {
 293                 clear_password.value = password.value;
 294             }
 295         });
 296     </script>";
 297 }
 298
 299 function jappixmini_settings_post(&$a,&$b) {
 300         // save addon settings for a user
 301
 302         if (!file_exists("addon/jappixmini/jappix")) return;
 303
 304         if(! local_user()) return;
 305         $uid = local_user();
 306
 307         if($_POST['jappixmini-submit']) {
 308                 $encrypt = intval($b['jappixmini-encrypt']);
 309                 if ($encrypt) {
 310                         // check that Jabber password was encrypted with correct Friendica password
 311                         $friendica_password = trim($b['jappixmini-friendica-password']);
 312                         $encrypted = hash('whirlpool',$friendica_password);
 313                         $r = q("SELECT * FROM `user` WHERE `uid`=$uid AND `password`='%s'",
 314                                 dbesc($encrypted)
 315                         );
 316                         if (!count($r)) {
 317                                 info("Wrong friendica password!");
 318                                 return;
 319                         }
 320                 }
 321
 322                 $purge = intval($b['jappixmini-purge']);
 323
 324                 $username = trim($b['jappixmini-username']);
 325                 $old_username = get_pconfig($uid,'jappixmini','username');
 326                 if ($username!=$old_username) $purge = 1;
 327
 328                 $server = trim($b['jappixmini-server']);
 329                 $old_server = get_pconfig($uid,'jappixmini','server');
 330                 if ($server!=$old_server) $purge = 1;
 331
 332                 set_pconfig($uid,'jappixmini','username',$username);
 333                 set_pconfig($uid,'jappixmini','server',$server);
 334                 set_pconfig($uid,'jappixmini','bosh',trim($b['jappixmini-bosh']));
 335                 set_pconfig($uid,'jappixmini','password',trim($b['jappixmini-encrypted-password']));
 336                 set_pconfig($uid,'jappixmini','autosubscribe',intval($b['jappixmini-autosubscribe']));
 337                 set_pconfig($uid,'jappixmini','autoapprove',intval($b['jappixmini-autoapprove']));
 338                 set_pconfig($uid,'jappixmini','activate',intval($b['jappixmini-activate']));
 339                 set_pconfig($uid,'jappixmini','encrypt',$encrypt);
 340                 info( 'Jappix Mini settings saved.' );
 341
 342                 if ($purge) {
 343                         q("DELETE FROM `pconfig` WHERE `uid`=$uid AND `cat`='jappixmini' and `k` LIKE 'id%%'");
 344                         info( 'List of addresses purged.' );
 345                 }
 346         }
 347 }
 348
 349 function jappixmini_script(&$a,&$s) {
 350     // adds the script to the page header which starts Jappix Mini
 351
 352     if (!file_exists("addon/jappixmini/jappix")) return;
 353     if(! local_user()) return;
 354
 355     $activate = get_pconfig(local_user(),'jappixmini','activate');
 356     if (!$activate) return;
 357
 358     $a->page['htmlhead'] .= '<script type="text/javascript" src="' . $a->get_baseurl() . '/addon/jappixmini/jappix/php/get.php?t=js&amp;g=mini.xml"></script>'."\r\n";
 359     $a->page['htmlhead'] .= '<script type="text/javascript" src="' . $a->get_baseurl() . '/addon/jappixmini/jappix/php/get.php?t=js&amp;f=presence.js"></script>'."\r\n";
 360
 361     $a->page['htmlhead'] .= '<script type="text/javascript" src="' . $a->get_baseurl() . '/addon/jappixmini/jappix/php/get.php?t=js&amp;f=caps.js"></script>'."\r\n";
 362     $a->page['htmlhead'] .= '<script type="text/javascript" src="' . $a->get_baseurl() . '/addon/jappixmini/jappix/php/get.php?t=js&amp;f=name.js"></script>'."\r\n";
 363     $a->page['htmlhead'] .= '<script type="text/javascript" src="' . $a->get_baseurl() . '/addon/jappixmini/jappix/php/get.php?t=js&amp;f=roster.js"></script>'."\r\n";
 364
 365     $a->page['htmlhead'] .= '<script type="text/javascript" src="' . $a->get_baseurl() . '/addon/jappixmini/lib.js"></script>'."\r\n";
 366
 367     $username = get_pconfig(local_user(),'jappixmini','username');
 368     $username = str_replace("'", "\\'", $username);
 369     $server = get_pconfig(local_user(),'jappixmini','server');
 370     $server = str_replace("'", "\\'", $server);
 371     $bosh = get_pconfig(local_user(),'jappixmini','bosh');
 372     $bosh = str_replace("'", "\\'", $bosh);
 373     $encrypt = get_pconfig(local_user(),'jappixmini','encrypt');
 374     $encrypt = intval($encrypt);
 375     $password = get_pconfig(local_user(),'jappixmini','password');
 376     $password = str_replace("'", "\\'", $password);
 377
 378     $autoapprove = get_pconfig(local_user(),'jappixmini','autoapprove');
 379     $autoapprove = intval($autoapprove);
 380     $autosubscribe = get_pconfig(local_user(),'jappixmini','autosubscribe');
 381     $autosubscribe = intval($autosubscribe);
 382
 383     // deactivate bosh host if proxy is off
 384     $conf = file_get_contents("addon/jappixmini/jappix/store/conf/main.xml");
 385     preg_match("/<bosh_proxy>(.*)<\/bosh_proxy>/", $conf, $matches);
 386     if ($matches[1]!="on") {
 387         $bosh = '';
 388     }
 389
 390     // get a list of jabber accounts of the contacts
 391     $contacts = Array();
 392     $uid = local_user();
 393     $rows = q("SELECT * FROM `pconfig` WHERE `uid`=$uid AND `cat`='jappixmini' and `k` LIKE 'id%%'");
 394     foreach ($rows as $row) {
 395         $key = $row['k'];
 396         $pos = strpos($key, ":");
 397         $dfrn_id = substr($key, $pos+1);
 398         $r = q("SELECT `name` FROM `contact` WHERE `uid`=$uid AND `dfrn-id`='%s' OR `issued-id`='%s'",
 399                 dbesc($dfrn_id),
 400                 dbesc($dfrn_id)
 401         );
 402         $name = $r[0]["name"];
 403
 404         $value = $row['v'];
 405         $pos = strpos($value, ":");
 406         $address = substr($value, $pos+1);
 407         if (!$address) continue;
 408         if (!$name) $name = $address;
 409
 410         $contacts[$address] = $name;
 411     }
 412     $contacts_json = json_encode($contacts);
 413
 414     // get nickname
 415     $r = q("SELECT `username` FROM `user` WHERE `uid`=$uid");
 416     $nickname = json_encode($r[0]["username"]);
 417
 418     // add javascript to start Jappix Mini
 419     $a->page['htmlhead'] .= "<script type=\"text/javascript\">
 420         jQuery(document).ready(function() {
 421            jappixmini_addon_start('$server', '$username', '$bosh', $encrypt, '$password', $nickname, $contacts_json, $autoapprove, $autosubscribe);
 422         });
 423     </script>";
 424
 425     return;
 426 }
 427
 428 function jappixmini_login(&$a, &$o) {
 429     // create client secret on login to be able to encrypt jabber passwords
 430
 431     if (!file_exists("addon/jappixmini/jappix")) return;
 432
 433     // for setDB, needed by jappixmini_addon_set_client_secret
 434     $a->page['htmlhead'] .= '<script type="text/javascript" src="' . $a->get_baseurl() . '/addon/jappixmini/jappix/php/get.php?t=js&amp;f=datastore.js"></script>'."\r\n";
 435
 436     // for str_sha1, needed by jappixmini_addon_set_client_secret
 437     $a->page['htmlhead'] .= '<script type="text/javascript" src="' . $a->get_baseurl() . '/addon/jappixmini/jappix/php/get.php?t=js&amp;f=jsjac.js"></script>'."\r\n";
 438
 439     // for jappixmini_addon_set_client_secret
 440     $a->page['htmlhead'] .= '<script type="text/javascript" src="' . $a->get_baseurl() . '/addon/jappixmini/lib.js"></script>'."\r\n";
 441
 442     // save hash of password
 443     $o = str_replace("<form ", "<form onsubmit=\"jappixmini_addon_set_client_secret(this.elements['id_password'].value);return true;\" ", $o);
 444 }
 445
 446 function jappixmini_cron(&$a, $d) {
 447         // For autosubscribe/autoapprove, we need to maintain a list of jabber addresses of our contacts.
 448
 449         if (!file_exists("addon/jappixmini/jappix")) return;
 450
 451         // go through list of users with jabber enabled
 452         $users = q("SELECT `uid` FROM `pconfig` WHERE `cat`='jappixmini' AND (`k`='autosubscribe' OR `k`='autoapprove') AND `v`='1'");
 453
 454         foreach ($users as $row) {
 455                 $uid = $row["uid"];
 456
 457                 // for each user, go through list of contacts
 458                 $contacts = q("SELECT * FROM `contact` WHERE `uid`=%d AND ((LENGTH(`dfrn-id`) AND LENGTH(`pubkey`)) OR (LENGTH(`issued-id`) AND LENGTH(`prvkey`)))", intval($uid));
 459                 foreach ($contacts as $contact_row) {
 460                         $request = $contact_row["request"];
 461                         if (!$request) continue;
 462
 463                         $dfrn_id = $contact_row["dfrn-id"];
 464                         if ($dfrn_id) {
 465                                 $key = $contact_row["pubkey"];
 466                                 $encrypt_func = openssl_public_encrypt;
 467                                 $decrypt_func = openssl_public_decrypt;
 468                                 $role = "prv";
 469                         } else {
 470                                 $dfrn_id = $contact_row["issued-id"];
 471                                 $key = $contact_row["prvkey"];
 472                                 $encrypt_func = openssl_private_encrypt;
 473                                 $decrypt_func = openssl_private_decrypt;
 474                                 $role = "pub";
 475                         }
 476
 477                         // check if jabber address already present
 478                         $present = get_pconfig($uid, "jappixmini", "id:".$dfrn_id);
 479                         $now = intval(time());
 480                         if ($present) {
 481                                 // $present has format "timestamp:jabber_address"
 482                                 $p = strpos($present, ":");
 483                                 $timestamp = intval(substr($present, 0, $p));
 484
 485                                 // do not re-retrieve jabber address if last retrieval
 486                                 // is not older than a week
 487                                 if ($now-$timestamp<3600*24*7) continue;
 488                         }
 489
 490                         // construct base retrieval address
 491                         $pos = strpos($request, "/dfrn_request/");
 492                         if ($pos===false) continue;
 493
 494                         $base = substr($request, 0, $pos)."/jappixmini?role=$role";
 495
 496                         // construct own address
 497                         $username = get_pconfig($uid, 'jappixmini', 'username');
 498                         if (!$username) continue;
 499                         $server = get_pconfig($uid, 'jappixmini', 'server');
 500                         if (!$server) continue;
 501
 502                         $address = $username."@".$server;
 503
 504                         // sign address
 505                         $signed_address = "";
 506                         $encrypt_func($address, $signed_address, $key);
 507
 508                         // construct request url
 509                         $signed_address_hex = bin2hex($signed_address);
 510                         $url = $base."&signed_address=$signed_address_hex&dfrn_id=".urlencode($dfrn_id);
 511
 512                         try {
 513                                 // send request
 514                                 $answer_json = fetch_url($url);
 515
 516                                 // parse answer
 517                                 $answer = json_decode($answer_json);
 518                                 if ($answer->status != "ok") throw new Exception();
 519
 520                                 $encrypted_address_hex = $answer->encrypted_address;
 521                                 if (!$encrypted_address_hex) throw new Exception();
 522
 523                                 $encrypted_address = hex2bin($encrypted_address_hex);
 524                                 if (!$encrypted_address) throw new Exception();
 525
 526                                 // decrypt address
 527                                 $decrypted_address = "";
 528                                 $decrypt_func($encrypted_address, $decrypted_address, $key);
 529                                 if (!$decrypted_address) throw new Exception();
 530                         } catch (Exception $e) {
 531                                 $decrypted_address = "";
 532                         }
 533
 534                         // save address
 535                         set_pconfig($uid, "jappixmini", "id:$dfrn_id", "$now:$decrypted_address");
 536                 }
 537         }
 538 }
 539
 540 function jappixmini_download_source(&$a,&$b) {
 541         // Jappix Mini source download link on About page
 542
 543         if (!file_exists("addon/jappixmini/jappix")) return;
 544
 545         $b .= '<h1>Jappix Mini</h1>';
 546         $b .= '<p>This site uses Jappix Mini by the <a href="'.$a->get_baseurl().'/addon/jappixmini/jappix/AUTHORS">Jappix authors</a>, which is distributed under the terms of the <a href="'.$a->get_baseurl().'/addon/jappixmini/jappix/COPYING">GNU Affero General Public License</a>.</p>';
 547         $b .= '<p>You can download the <a href="'.$a->get_baseurl().'/addon/jappixmini/jappix.zip">source code</a>.</p>';
 548 }