/**
* Dispath one message
* @param callback if not NULL, each packet will be processed with this function;
* in case that function returns TRUE, packet won't be processed
* by dispather, but will be returned;
* function has to accept one argument (whole packet /with
* leading packet type byte) and return boolean
*
* @return string|NULL string if packet was catched by return filter, NULL
* otherwise
*/
public function dispatch($return_filter = NULL)
{
if ($return_filter !== NULL && !is_callable($return_filter)) {
throw new Error('Given callback is not callable.');
}
$packet = $this->protocol->receive();
if ($return_filter !== NULL) {
if ($return_filter($packet)) {
return $packet;
}
}
list($packet_type) = parse('b', $packet);
if (!isset($this->callbacks[$packet_type])) {
$this->protocol->send('bu', SSH_MSG_UNIMPLEMENTED, $this->protocol->getReceiveSeq());
return NULL;
}
$callback = $this->callbacks[$packet_type];
if ($callback === NULL) {
return NULL;
}
$callback($packet);
return NULL;
}
/**
* @param string
* @return bool
*/
public function authenticate(PacketProtocol $protocol, $packet)
{
if ($this->user) {
$protocol->send('bnb', SSH_MSG_USERAUTH_FAILURE, array(), 0);
return FALSE;
}
list($user, $service, $method) = parse('sss', $packet);
if ($service !== 'ssh-connection' || $method !== 'publickey') {
$protocol->send('bnb', SSH_MSG_USERAUTH_FAILURE, array('publickey'), 0);
return FALSE;
}
list($signed, $publickey_algorithm, $publickey) = parse('bss', $packet);
// FIXME: currently on ssh-rsa supported
if ($publickey_algorithm !== 'ssh-rsa' || ($content = @file_get_contents($this->dir . '/' . $user)) === FALSE) {
$protocol->send('bnb', SSH_MSG_USERAUTH_FAILURE, array('publickey'), 0);
return FALSE;
}
if (!$signed) {
$protocol->send('bss', SSH_MSG_USERAUTH_PK_OK, $publickey_algorithm, $publickey);
return FALSE;
}
list($signature) = parse('s', $packet);
list($known_publickey_algorithm, $known_publickey, ) = explode(' ', trim($content), 3);
$known_publickey = base64_decode($known_publickey);
if (!($known_publickey_algorithm === $publickey_algorithm && $known_publickey === $publickey)) {
$protocol->send('bnb', SSH_MSG_USERAUTH_FAILURE, array('publickey'), 0);
return FALSE;
}
$data = format('sbsssbss', $protocol->getSessionId(), SSH_MSG_USERAUTH_REQUEST, $user, $service, 'publickey', 1, $publickey_algorithm, $publickey);
if (verify($publickey, $data, $signature)) {
$protocol->send('b', SSH_MSG_USERAUTH_SUCCESS);
$this->user = $user;
$this->service = $service;
return TRUE;
}
return FALSE;
}
/**
* @param string
* @return int
*/
public function stream_write($data)
{
if ($this->window_size < strlen($data)) {
$this->protocol->send('buu', SSH_MSG_CHANNEL_WINDOW_ADJUST, $this->channel, 0x7fffffff);
}
$this->protocol->send('buus', SSH_MSG_CHANNEL_EXTENDED_DATA, $this->channel, SSH_EXTENDED_DATA_STDERR, $data);
$this->window_size -= strlen($data);
return strlen($data);
}
