1
0
mirror of https://github.com/danog/tgseclib.git synced 2024-12-04 02:27:52 +01:00
tgseclib/phpseclib/Crypt/Common/AsymmetricKey.php
2017-02-02 20:20:47 -05:00

661 lines
16 KiB
PHP

<?php
/**
* Base Class for all asymmetric key ciphers
*
* PHP version 5
*
* @category Crypt
* @package AsymmetricKey
* @author Jim Wigginton <terrafrost@php.net>
* @copyright 2016 Jim Wigginton
* @license http://www.opensource.org/licenses/mit-license.html MIT License
* @link http://phpseclib.sourceforge.net
*/
namespace phpseclib\Crypt\Common;
use phpseclib\Math\BigInteger;
use phpseclib\Crypt\Hash;
use ParagonIE\ConstantTime\Base64;
/**
* Base Class for all stream cipher classes
*
* @package AsymmetricKey
* @author Jim Wigginton <terrafrost@php.net>
*/
abstract class AsymmetricKey
{
/**
* Precomputed Zero
*
* @var \phpseclib\Math\BigInteger
* @access private
*/
protected static $zero;
/**
* Precomputed One
*
* @var \phpseclib\Math\BigInteger
* @access private
*/
protected static $one;
/**
* Engine
*
* This is only used for key generation. Valid values are RSA::ENGINE_INTERNAL and RSA::ENGINE_OPENSSL
*
* @var int
* @access private
*/
protected static $engine = NULL;
/**
* OpenSSL configuration file name.
*
* Set to null to use system configuration file.
*
* @see self::createKey()
* @var mixed
* @access public
*/
protected static $configFile;
/**
* Supported plugins (lower case)
*
* @see self::initialize_static_variables()
* @var array
* @access private
*/
private static $plugins = [];
/**
* Supported plugins (original case)
*
* @see self::initialize_static_variables()
* @var array
* @access private
*/
private static $origPlugins = [];
/**
* Supported signature formats (lower case)
*
* @see self::initialize_static_variables()
* @var array
* @access private
*/
private static $signatureFormats = [];
/**
* Supported signature formats (original case)
*
* @see self::initialize_static_variables()
* @var array
* @access private
*/
private static $signatureFileFormats = [];
/**
* Password
*
* @var string
* @access private
*/
protected $password = false;
/**
* Loaded File Format
*
* @var string
* @access private
*/
protected $format = false;
/**
* Private Key Format
*
* @var string
* @access private
*/
protected $privateKeyFormat = 'PKCS8';
/**
* Public Key Format
*
* @var string
* @access private
*/
protected $publicKeyFormat = 'PKCS8';
/**
* Hash function
*
* @var \phpseclib\Crypt\Hash
* @access private
*/
protected $hash;
/**
* HMAC function
*
* @var \phpseclib\Crypt\Hash
* @access private
*/
private $hmac;
/**#@+
* @access private
* @see self::__construct()
*/
/**
* To use the pure-PHP implementation
*/
const ENGINE_INTERNAL = 1;
/**
* To use the OpenSSL library
*
* (if enabled; otherwise, the internal implementation will be used)
*/
const ENGINE_OPENSSL = 2;
/**#@-*/
/**
* The constructor
*
* @access public
*/
public function __construct()
{
self::initialize_static_variables();
$this->hash = new Hash('sha256');
$this->hmac = new Hash('sha256');
}
/**
* Tests engine validity
*
* @access public
* @param int $val
*/
public static function isValidEngine($val)
{
switch ($val) {
case self::ENGINE_OPENSSL:
return extension_loaded('openssl') && file_exists(self::$configFile);
case self::ENGINE_INTERNAL:
return true;
}
return false;
}
/**
* Sets the engine
*
* Only used in RSA::createKey. Valid values are RSA::ENGINE_OPENSSL and RSA::ENGINE_INTERNAL
*
* @access public
* @param int $val
*/
public static function setPreferredEngine($val)
{
static::$engine = null;
$candidateEngines = [
$val,
self::ENGINE_OPENSSL
];
foreach ($candidateEngines as $engine) {
if (static::isValidEngine($engine)) {
static::$engine = $engine;
break;
}
}
if (!isset(static::$engine)) {
static::$engine = self::ENGINE_INTERNAL;
}
}
/**
* Returns the engine
*
* @access public
* @return int
*/
public static function getEngine()
{
return self::$engine;
}
/**
* Initialize static variables
*
* @access private
*/
protected static function initialize_static_variables()
{
if (!isset(self::$zero)) {
self::$zero= new BigInteger(0);
self::$one = new BigInteger(1);
self::$configFile = __DIR__ . '/../openssl.cnf';
}
self::loadPlugins('Keys');
if (static::ALGORITHM != 'RSA') {
self::loadPlugins('Signature');
}
}
/**
* Load Plugins
*
* @params $format
* @access private
*/
private static function loadPlugins($format)
{
if (!isset(self::$plugins[static::ALGORITHM][$format])) {
self::$plugins[static::ALGORITHM][$format] = [];
foreach (glob(__DIR__ . '/../' . static::ALGORITHM . '/' . $format . '/*.php') as $file) {
$name = pathinfo($file, PATHINFO_FILENAME);
$type = 'phpseclib\Crypt\\' . static::ALGORITHM . '\\' . $format . '\\' . $name;
self::$plugins[static::ALGORITHM][$format][strtolower($name)] = $type;
self::$origPlugins[static::ALGORITHM][$format][] = $name;
}
}
}
/**
* Validate Plugin
*
* @access private
* @param string $format
* @param string $type
* @param string $method optional
* @return mixed
*/
protected static function validatePlugin($format, $type, $method = NULL)
{
$type = strtolower($type);
if (!isset(self::$plugins[static::ALGORITHM][$format][$type])) {
return false;
}
$type = self::$plugins[static::ALGORITHM][$format][$type];
if (isset($method) && !method_exists($type, $method)) {
return false;
}
return $type;
}
/**
* Load the key
*
* @access private
* @param string $key
* @param string $type
* @return array
*/
protected function load($key, $type)
{
$components = false;
if ($type === false) {
foreach (self::$plugins[static::ALGORITHM]['Keys'] as $format) {
try {
$components = $format::load($key, $this->password);
} catch (\Exception $e) {
$components = false;
}
if ($components !== false) {
break;
}
}
} else {
$format = strtolower($type);
if (isset(self::$plugins[static::ALGORITHM]['Keys'][$format])) {
$format = self::$plugins[static::ALGORITHM]['Keys'][$format];
$components = $format::load($key, $this->password);
}
}
if ($components === false) {
$this->format = false;
return false;
}
$this->format = $format;
return $components;
}
/**
* Load the public key
*
* @access private
* @param string $key
* @param string $type
* @return array
*/
protected function setPublicKey($key, $type)
{
$components = false;
if ($type === false) {
foreach (self::$plugins[static::ALGORITHM]['Keys'] as $format) {
if (!method_exists($format, 'savePublicKey')) {
continue;
}
try {
$components = $format::load($key, $this->password);
} catch (\Exception $e) {
$components = false;
}
if ($components !== false) {
break;
}
}
} else {
$format = strtolower($type);
if (isset(self::$plugins[static::ALGORITHM]['Keys'][$format])) {
$format = self::$plugins[static::ALGORITHM]['Keys'][$format];
$components = $format::load($key, $this->password);
}
}
if ($components === false) {
$this->format = false;
return false;
}
$this->format = $format;
return $components;
}
/**
* Returns a list of supported formats.
*
* @access public
* @return array
*/
public static function getSupportedKeyFormats()
{
self::initialize_static_variables();
return self::$plugins[static::ALGORITHM]['Keys'];
}
/**
* Add a fileformat plugin
*
* The plugin needs to either already be loaded or be auto-loadable.
* Loading a plugin whose shortname overwrite an existing shortname will overwrite the old plugin.
*
* @see self::load()
* @param string $fullname
* @access public
* @return bool
*/
public static function addFileFormat($fullname)
{
self::initialize_static_variables();
if (class_exists($fullname)) {
$meta = new \ReflectionClass($path);
$shortname = $meta->getShortName();
self::$plugins[static::ALGORITHM]['Keys'][strtolower($shortname)] = $fullname;
self::$origPlugins[static::ALGORITHM]['Keys'][] = $shortname;
}
}
/**
* Returns the public key's fingerprint
*
* The public key's fingerprint is returned, which is equivalent to running `ssh-keygen -lf rsa.pub`. If there is
* no public key currently loaded, false is returned.
* Example output (md5): "c1:b1:30:29:d7:b8:de:6c:97:77:10:d7:46:41:63:87" (as specified by RFC 4716)
*
* @access public
* @param string $algorithm The hashing algorithm to be used. Valid options are 'md5' and 'sha256'. False is returned
* for invalid values.
* @return mixed
*/
public function getPublicKeyFingerprint($algorithm = 'md5')
{
$type = self::validatePlugin('Keys', 'OpenSSH', 'getBinaryOutput');
if ($type === false) {
return false;
}
$status = $type::getBinaryOutput();
$type::setBinaryOutput(true);
$key = $this->getPublicKey('OpenSSH');
if ($key === false) {
return false;
}
$type::setBinaryOutput($status);
switch ($algorithm) {
case 'sha256':
$hash = new Hash('sha256');
$base = Base64::encode($hash->hash($key));
return substr($base, 0, strlen($base) - 1);
case 'md5':
return substr(chunk_split(md5($key), 2, ':'), 0, -1);
default:
return false;
}
}
/**
* __toString() magic method
*
* @access public
* @return string
*/
public function __toString()
{
try {
$key = $this->getPrivateKey($this->privateKeyFormat);
if (is_string($key)) {
return $key;
}
$key = $this->getPublicKey($this->publicKeyFormat);
return is_string($key) ? $key : '';
} catch (\Exception $e) {
return '';
}
}
/**
* __clone() magic method
*
* @access public
* @return static
*/
public function __clone()
{
$key = new static();
$key->load($this);
return $key;
}
/**
* Determines the private key format
*
* @see self::__toString()
* @access public
* @param string $format
*/
public function setPrivateKeyFormat($format)
{
$this->privateKeyFormat = $format;
}
/**
* Determines the public key format
*
* @see self::__toString()
* @access public
* @param string $format
*/
public function setPublicKeyFormat($format)
{
$this->publicKeyFormat = $format;
}
/**
* Returns the format of the loaded key.
*
* If the key that was loaded wasn't in a valid or if the key was auto-generated
* with RSA::createKey() then this will return false.
*
* @see self::load()
* @access public
* @return mixed
*/
public function getLoadedFormat()
{
if ($this->format === false) {
return false;
}
$meta = new \ReflectionClass($this->format);
return $meta->getShortName();
}
/**
* Sets the password
*
* Private keys can be encrypted with a password. To unset the password, pass in the empty string or false.
* Or rather, pass in $password such that empty($password) && !is_string($password) is true.
*
* @see self::createKey()
* @see self::load()
* @access public
* @param string $password
*/
public function setPassword($password = false)
{
$this->password = $password;
}
/**
* Determines which hashing function should be used
*
* @access public
* @param string $hash
*/
public function setHash($hash)
{
$this->hash = new Hash($hash);
$this->hmac = new Hash($hash);
}
/**
* Compute the pseudorandom k for signature generation,
* using the process specified for deterministic DSA.
*
* @access public
* @param string $h1
* @return string
*/
protected function computek($h1)
{
$v = str_repeat("\1", strlen($h1));
$k = str_repeat("\0", strlen($h1));
$x = $this->int2octets($this->x);
$h1 = $this->bits2octets($h1);
$this->hmac->setKey($k);
$k = $this->hmac->hash($v . "\0" . $x . $h1);
$this->hmac->setKey($k);
$v = $this->hmac->hash($v);
$k = $this->hmac->hash($v . "\1" . $x . $h1);
$this->hmac->setKey($k);
$v = $this->hmac->hash($v);
$qlen = $this->q->getLengthInBytes();
while (true) {
$t = '';
while (strlen($t) < $qlen) {
$v = $this->hmac->hash($v);
$t = $t . $v;
}
$k = $this->bits2int($t);
if (!$k->equals(self::$zero) && $k->compare($this->q) < 0) {
break;
}
$k = $this->hmac->hash($v . "\0");
$this->hmac->setKey($k);
$v = $this->hmac->hash($v);
}
return $k;
}
/**
* Integer to Octet String
*
* @access private
* @param \phpseclib\Math\BigInteger $v
* @return string
*/
private function int2octets($v)
{
$out = $v->toBytes();
$rolen = $this->q->getLengthInBytes();
if (strlen($out) < $rolen) {
return str_pad($out, $rolen, "\0", STR_PAD_LEFT);
} else if (strlen($out) > $rolen) {
return substr($out, -$rolen);
} else {
return $out;
}
}
/**
* Bit String to Integer
*
* @access private
* @param string $in
* @return \phpseclib\Math\BigInteger
*/
protected function bits2int($in)
{
$v = new BigInteger($in, 256);
$vlen = strlen($in) << 3;
$qlen = $this->q->getLength();
if ($vlen > $qlen) {
return $v->bitwise_rightShift($vlen - $qlen);
}
return $v;
}
/**
* Bit String to Octet String
*
* @access private
* @param string $in
* @return string
*/
private function bits2octets($in)
{
$z1 = $this->bits2int($in);
$z2 = $z1->subtract($this->q);
return $z2->compare(self::$zero) < 0 ?
$this->int2octets($z1) :
$this->int2octets($z2);
}
}