friendica-github/mod/dfrn_notify.php
2017-12-07 09:04:24 -05:00

343 lines
11 KiB
PHP

<?php
/**
* @file mod/dfrn_notify.php
* @brief The dfrn notify endpoint
* @see PDF with dfrn specs: https://github.com/friendica/friendica/blob/master/spec/dfrn2.pdf
*/
use Friendica\App;
use Friendica\Core\Config;
use Friendica\Database\DBM;
use Friendica\Model\Contact;
use Friendica\Protocol\DFRN;
require_once 'include/items.php';
require_once 'include/event.php';
function dfrn_notify_post(App $a) {
logger(__function__, LOGGER_TRACE);
$dfrn_id = ((x($_POST,'dfrn_id')) ? notags(trim($_POST['dfrn_id'])) : '');
$dfrn_version = ((x($_POST,'dfrn_version')) ? (float) $_POST['dfrn_version'] : 2.0);
$challenge = ((x($_POST,'challenge')) ? notags(trim($_POST['challenge'])) : '');
$data = ((x($_POST,'data')) ? $_POST['data'] : '');
$key = ((x($_POST,'key')) ? $_POST['key'] : '');
$rino_remote = ((x($_POST,'rino')) ? intval($_POST['rino']) : 0);
$dissolve = ((x($_POST,'dissolve')) ? intval($_POST['dissolve']) : 0);
$perm = ((x($_POST,'perm')) ? notags(trim($_POST['perm'])) : 'r');
$ssl_policy = ((x($_POST,'ssl_policy')) ? notags(trim($_POST['ssl_policy'])): 'none');
$page = ((x($_POST,'page')) ? intval($_POST['page']) : 0);
$forum = (($page == 1) ? 1 : 0);
$prv = (($page == 2) ? 1 : 0);
$writable = (-1);
if ($dfrn_version >= 2.21) {
$writable = (($perm === 'rw') ? 1 : 0);
}
$direction = (-1);
if (strpos($dfrn_id, ':') == 1) {
$direction = intval(substr($dfrn_id, 0, 1));
$dfrn_id = substr($dfrn_id, 2);
}
$r = q("SELECT * FROM `challenge` WHERE `dfrn-id` = '%s' AND `challenge` = '%s' LIMIT 1",
dbesc($dfrn_id),
dbesc($challenge)
);
if (! DBM::is_result($r)) {
logger('dfrn_notify: could not match challenge to dfrn_id ' . $dfrn_id . ' challenge=' . $challenge);
xml_status(3, 'Could not match challenge');
}
$r = q("DELETE FROM `challenge` WHERE `dfrn-id` = '%s' AND `challenge` = '%s'",
dbesc($dfrn_id),
dbesc($challenge)
);
// find the local user who owns this relationship.
$sql_extra = '';
switch ($direction) {
case (-1):
$sql_extra = sprintf(" AND ( `issued-id` = '%s' OR `dfrn-id` = '%s' ) ", dbesc($dfrn_id), dbesc($dfrn_id));
break;
case 0:
$sql_extra = sprintf(" AND `issued-id` = '%s' AND `duplex` = 1 ", dbesc($dfrn_id));
break;
case 1:
$sql_extra = sprintf(" AND `dfrn-id` = '%s' AND `duplex` = 1 ", dbesc($dfrn_id));
break;
default:
xml_status(3, 'Invalid direction');
break; // NOTREACHED
}
/*
* be careful - $importer will contain both the contact information for the contact
* sending us the post, and also the user information for the person receiving it.
* since they are mixed together, it is easy to get them confused.
*/
$r = q("SELECT `contact`.*, `contact`.`uid` AS `importer_uid`,
`contact`.`pubkey` AS `cpubkey`,
`contact`.`prvkey` AS `cprvkey`,
`contact`.`thumb` AS `thumb`,
`contact`.`url` as `url`,
`contact`.`name` as `senderName`,
`user`.*
FROM `contact`
LEFT JOIN `user` ON `contact`.`uid` = `user`.`uid`
WHERE `contact`.`blocked` = 0 AND `contact`.`pending` = 0
AND `user`.`nickname` = '%s' AND `user`.`account_expired` = 0 AND `user`.`account_removed` = 0 $sql_extra LIMIT 1",
dbesc($a->argv[1])
);
if (! DBM::is_result($r)) {
logger('dfrn_notify: contact not found for dfrn_id ' . $dfrn_id);
xml_status(3, 'Contact not found');
//NOTREACHED
}
// $importer in this case contains the contact record for the remote contact joined with the user record of our user.
$importer = $r[0];
logger("Remote rino version: ".$rino_remote." for ".$importer["url"], LOGGER_DEBUG);
if ((($writable != (-1)) && ($writable != $importer['writable'])) || ($importer['forum'] != $forum) || ($importer['prv'] != $prv)) {
q("UPDATE `contact` SET `writable` = %d, forum = %d, prv = %d WHERE `id` = %d",
intval(($writable == (-1)) ? $importer['writable'] : $writable),
intval($forum),
intval($prv),
intval($importer['id'])
);
if ($writable != (-1)) {
$importer['writable'] = $writable;
}
$importer['forum'] = $page;
}
// if contact's ssl policy changed, update our links
fix_contact_ssl_policy($importer,$ssl_policy);
logger('dfrn_notify: received notify from ' . $importer['name'] . ' for ' . $importer['username']);
logger('dfrn_notify: data: ' . $data, LOGGER_DATA);
if ($dissolve == 1) {
// Relationship is dissolved permanently
Contact::remove($importer['id']);
logger('relationship dissolved : ' . $importer['name'] . ' dissolved ' . $importer['username']);
xml_status(0, 'relationship dissolved');
}
$rino = Config::get('system', 'rino_encrypt');
$rino = intval($rino);
logger("Local rino version: " . $rino, LOGGER_DEBUG);
if (strlen($key)) {
// if local rino is lower than remote rino, abort: should not happen!
// but only for $remote_rino > 1, because old code did't send rino version
if ($rino_remote_version > 1 && $rino < $rino_remote) {
logger("rino version '$rino_remote' is lower than supported '$rino'");
xml_status(0, "rino version '$rino_remote' is lower than supported '$rino'");
}
$rawkey = hex2bin(trim($key));
logger('rino: md5 raw key: ' . md5($rawkey));
$final_key = '';
if ($dfrn_version >= 2.1) {
if ((($importer['duplex']) && strlen($importer['cprvkey'])) || (! strlen($importer['cpubkey']))) {
openssl_private_decrypt($rawkey, $final_key, $importer['cprvkey']);
} else {
openssl_public_decrypt($rawkey, $final_key, $importer['cpubkey']);
}
} else {
if ((($importer['duplex']) && strlen($importer['cpubkey'])) || (! strlen($importer['cprvkey']))) {
openssl_public_decrypt($rawkey, $final_key, $importer['cpubkey']);
} else {
openssl_private_decrypt($rawkey, $final_key, $importer['cprvkey']);
}
}
#logger('rino: received key : ' . $final_key);
switch($rino_remote) {
case 0:
case 1:
/*
*we got a key. old code send only the key, without RINO version.
* we assume RINO 1 if key and no RINO version
*/
$data = DFRN::aesDecrypt(hex2bin($data), $final_key);
break;
case 2:
try {
$data = \Crypto::decrypt(hex2bin($data), $final_key);
} catch (\InvalidCiphertextException $ex) { // VERY IMPORTANT
/*
* Either:
* 1. The ciphertext was modified by the attacker,
* 2. The key is wrong, or
* 3. $ciphertext is not a valid ciphertext or was corrupted.
* Assume the worst.
*/
logger('The ciphertext has been tampered with!');
xml_status(0, 'The ciphertext has been tampered with!');
} catch (\CryptoTestFailedException $ex) {
logger('Cannot safely perform dencryption');
xml_status(0, 'CryptoTestFailed');
} catch (\CannotPerformOperationException $ex) {
logger('Cannot safely perform decryption');
xml_status(0, 'Cannot safely perform decryption');
}
break;
default:
logger("rino: invalid sent version '$rino_remote'");
xml_status(0, "Invalid sent version '$rino_remote'");
}
logger('rino: decrypted data: ' . $data, LOGGER_DATA);
}
$ret = DFRN::import($data, $importer);
xml_status($ret, 'Processed');
// NOTREACHED
}
function dfrn_notify_content(App $a) {
if(x($_GET,'dfrn_id')) {
/*
* initial communication from external contact, $direction is their direction.
* If this is a duplex communication, ours will be the opposite.
*/
$dfrn_id = notags(trim($_GET['dfrn_id']));
$dfrn_version = (float) $_GET['dfrn_version'];
$rino_remote = ((x($_GET,'rino')) ? intval($_GET['rino']) : 0);
$type = "";
$last_update = "";
logger('dfrn_notify: new notification dfrn_id=' . $dfrn_id);
$direction = (-1);
if(strpos($dfrn_id,':') == 1) {
$direction = intval(substr($dfrn_id,0,1));
$dfrn_id = substr($dfrn_id,2);
}
$hash = random_string();
$status = 0;
$r = q("DELETE FROM `challenge` WHERE `expire` < " . intval(time()));
$r = q("INSERT INTO `challenge` ( `challenge`, `dfrn-id`, `expire` , `type`, `last_update` )
VALUES( '%s', '%s', %d, '%s', '%s' ) ",
dbesc($hash),
dbesc($dfrn_id),
intval(time() + 90 ),
dbesc($type),
dbesc($last_update)
);
logger('dfrn_notify: challenge=' . $hash, LOGGER_DEBUG);
$sql_extra = '';
switch($direction) {
case (-1):
$sql_extra = sprintf(" AND ( `issued-id` = '%s' OR `dfrn-id` = '%s' ) ", dbesc($dfrn_id), dbesc($dfrn_id));
$my_id = $dfrn_id;
break;
case 0:
$sql_extra = sprintf(" AND `issued-id` = '%s' AND `duplex` = 1 ", dbesc($dfrn_id));
$my_id = '1:' . $dfrn_id;
break;
case 1:
$sql_extra = sprintf(" AND `dfrn-id` = '%s' AND `duplex` = 1 ", dbesc($dfrn_id));
$my_id = '0:' . $dfrn_id;
break;
default:
$status = 1;
break; // NOTREACHED
}
$r = q("SELECT `contact`.*, `user`.`nickname`, `user`.`page-flags` FROM `contact` LEFT JOIN `user` ON `user`.`uid` = `contact`.`uid`
WHERE `contact`.`blocked` = 0 AND `contact`.`pending` = 0 AND `user`.`nickname` = '%s'
AND `user`.`account_expired` = 0 AND `user`.`account_removed` = 0 $sql_extra LIMIT 1",
dbesc($a->argv[1])
);
if (! DBM::is_result($r)) {
$status = 1;
}
logger("Remote rino version: ".$rino_remote." for ".$r[0]["url"], LOGGER_DEBUG);
$challenge = '';
$encrypted_id = '';
$id_str = $my_id . '.' . mt_rand(1000,9999);
$prv_key = trim($r[0]['prvkey']);
$pub_key = trim($r[0]['pubkey']);
$dplx = intval($r[0]['duplex']);
if ((($dplx) && (strlen($prv_key))) || ((strlen($prv_key)) && (!(strlen($pub_key))))) {
openssl_private_encrypt($hash, $challenge, $prv_key);
openssl_private_encrypt($id_str, $encrypted_id, $prv_key);
} elseif (strlen($pub_key)) {
openssl_public_encrypt($hash, $challenge, $pub_key);
openssl_public_encrypt($id_str, $encrypted_id, $pub_key);
} else {
/// @TODO these kind of else-blocks are making the code harder to understand
$status = 1;
}
$challenge = bin2hex($challenge);
$encrypted_id = bin2hex($encrypted_id);
$rino = Config::get('system', 'rino_encrypt');
$rino = intval($rino);
logger("Local rino version: ". $rino, LOGGER_DEBUG);
// if requested rino is lower than enabled local rino, lower local rino version
// if requested rino is higher than enabled local rino, reply with local rino
if ($rino_remote < $rino) {
$rino = $rino_remote;
}
if((($r[0]['rel']) && ($r[0]['rel'] != CONTACT_IS_SHARING)) || ($r[0]['page-flags'] == PAGE_COMMUNITY)) {
$perm = 'rw';
} else {
$perm = 'r';
}
header("Content-type: text/xml");
echo '<?xml version="1.0" encoding="UTF-8"?>' . "\r\n"
. '<dfrn_notify>' . "\r\n"
. "\t" . '<status>' . $status . '</status>' . "\r\n"
. "\t" . '<dfrn_version>' . DFRN_PROTOCOL_VERSION . '</dfrn_version>' . "\r\n"
. "\t" . '<rino>' . $rino . '</rino>' . "\r\n"
. "\t" . '<perm>' . $perm . '</perm>' . "\r\n"
. "\t" . '<dfrn_id>' . $encrypted_id . '</dfrn_id>' . "\r\n"
. "\t" . '<challenge>' . $challenge . '</challenge>' . "\r\n"
. '</dfrn_notify>' . "\r\n" ;
killme();
}
}