public function createCsrfKey()
{
$csrfKey = '';
while (strlen($csrfKey) <= 50) {
$csrfKey .= base_convert(crypt_random(), 10, 32);
}
return $csrfKey;
}
/**
* Generates a random string x bytes long
*
* @access private
* @static
* @param Integer $bytes
* @param optional Integer $nonzero
* @return String
*/
private static function _random($bytes, $nonzero = false)
{
$temp = '';
if ($nonzero) {
for ($i = 0; $i < $bytes; $i++) {
$temp .= chr(crypt_random(1, 255));
}
} else {
$ints = $bytes + 1 >> 2;
for ($i = 0; $i < $ints; $i++) {
$temp .= pack('N', crypt_random());
}
$temp = substr($temp, 0, $bytes);
}
return $temp;
}
/**
* Sends Binary Packets
*
* See '6. Binary Packet Protocol' of rfc4253 for more info.
*
* @param String $data
* @see Net_SSH2::_get_binary_packet()
* @return Boolean
* @access private
*/
function _send_binary_packet($data)
{
if (feof($this->fsock)) {
user_error('Connection closed prematurely', E_USER_NOTICE);
return false;
}
//if ($this->compress) {
// // the -4 removes the checksum:
// // http://php.net/function.gzcompress#57710
// $data = substr(gzcompress($data), 0, -4);
//}
// 4 (packet length) + 1 (padding length) + 4 (minimal padding amount) == 9
$packet_length = strlen($data) + 9;
// round up to the nearest $this->encrypt_block_size
$packet_length += ($this->encrypt_block_size - 1) * $packet_length % $this->encrypt_block_size;
// subtracting strlen($data) is obvious - subtracting 5 is necessary because of packet_length and padding_length
$padding_length = $packet_length - strlen($data) - 5;
$padding = '';
for ($i = 0; $i < $padding_length; $i++) {
$padding .= chr(crypt_random(0, 255));
}
// we subtract 4 from packet_length because the packet_length field isn't supposed to include itself
$packet = pack('NCa*', $packet_length - 4, $padding_length, $data . $padding);
$hmac = $this->hmac_create !== false ? $this->hmac_create->hash(pack('Na*', $this->send_seq_no, $packet)) : '';
$this->send_seq_no++;
if ($this->encrypt !== false) {
$packet = $this->encrypt->encrypt($packet);
}
$packet .= $hmac;
$start = strtok(microtime(), ' ') + strtok('');
// http://php.net/microtime#61838
$result = strlen($packet) == fputs($this->fsock, $packet);
$stop = strtok(microtime(), ' ') + strtok('');
if (defined('NET_SSH2_LOGGING')) {
$temp = isset($this->message_numbers[ord($data[0])]) ? $this->message_numbers[ord($data[0])] : 'UNKNOWN (' . ord($data[0]) . ')';
$this->message_number_log[] = '-> ' . $temp . ' (' . round($stop - $start, 4) . 's)';
if (NET_SSH2_LOGGING == NET_SSH2_LOG_COMPLEX) {
$this->message_log[] = substr($data, 1);
}
}
return $result;
}
/**
* Generates a random string x bytes long
*
* @access public
* @param Integer $bytes
* @param optional Integer $nonzero
* @return String
*/
function _random($bytes, $nonzero = false)
{
$temp = '';
for ($i = 0; $i < $bytes; $i++) {
$temp .= chr(crypt_random($nonzero, 255));
}
return $temp;
}
/**
* RSA Encrypt
*
* Returns mod(pow($m, $e), $n), where $n should be the product of two (large) primes $p and $q and where $e
* should be a number with the property that gcd($e, ($p - 1) * ($q - 1)) == 1. Could just make anything that
* calls this call modexp, instead, but I think this makes things clearer, maybe...
*
* @see Net_SSH1::Net_SSH1()
* @param Math_BigInteger $m
* @param Array $key
* @return Math_BigInteger
* @access private
*/
function _rsa_crypt($m, $key)
{
/*
if (!class_exists('Crypt_RSA')) {
require_once('Crypt/RSA.php');
}
$rsa = new Crypt_RSA();
$rsa->loadKey($key, CRYPT_RSA_PUBLIC_FORMAT_RAW);
$rsa->setEncryptionMode(CRYPT_RSA_ENCRYPTION_PKCS1);
return $rsa->encrypt($m);
*/
// To quote from protocol-1.5.txt:
// The most significant byte (which is only partial as the value must be
// less than the public modulus, which is never a power of two) is zero.
//
// The next byte contains the value 2 (which stands for public-key
// encrypted data in the PKCS standard [PKCS#1]). Then, there are non-
// zero random bytes to fill any unused space, a zero byte, and the data
// to be encrypted in the least significant bytes, the last byte of the
// data in the least significant byte.
// Presumably the part of PKCS#1 they're refering to is "Section 7.2.1 Encryption Operation",
// under "7.2 RSAES-PKCS1-v1.5" and "7 Encryption schemes" of the following URL:
// ftp://ftp.rsasecurity.com/pub/pkcs/pkcs-1/pkcs-1v2-1.pdf
$temp = chr(0) . chr(2);
$modulus = $key[1]->toBytes();
$length = strlen($modulus) - strlen($m) - 3;
for ($i = 0; $i < $length; $i++) {
$temp .= chr(crypt_random(1, 255));
}
$temp .= chr(0) . $m;
$m = new Math_BigInteger($temp, 256);
$m = $m->modPow($key[0], $key[1]);
return $m->toBytes();
}