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Diffstat (limited to 'phpsec/Crypt/RSA.php')
| -rw-r--r-- | phpsec/Crypt/RSA.php | 2119 |
1 files changed, 2119 insertions, 0 deletions
diff --git a/phpsec/Crypt/RSA.php b/phpsec/Crypt/RSA.php new file mode 100644 index 000000000..1c562082b --- /dev/null +++ b/phpsec/Crypt/RSA.php @@ -0,0 +1,2119 @@ +<?php
+/* vim: set expandtab tabstop=4 shiftwidth=4 softtabstop=4: */
+
+/**
+ * Pure-PHP PKCS#1 (v2.1) compliant implementation of RSA.
+ *
+ * PHP versions 4 and 5
+ *
+ * Here's an example of how to encrypt and decrypt text with this library:
+ * <code>
+ * <?php
+ * include('Crypt/RSA.php');
+ *
+ * $rsa = new Crypt_RSA();
+ * extract($rsa->createKey());
+ *
+ * $plaintext = 'terrafrost';
+ *
+ * $rsa->loadKey($privatekey);
+ * $ciphertext = $rsa->encrypt($plaintext);
+ *
+ * $rsa->loadKey($publickey);
+ * echo $rsa->decrypt($ciphertext);
+ * ?>
+ * </code>
+ *
+ * Here's an example of how to create signatures and verify signatures with this library:
+ * <code>
+ * <?php
+ * include('Crypt/RSA.php');
+ *
+ * $rsa = new Crypt_RSA();
+ * extract($rsa->createKey());
+ *
+ * $plaintext = 'terrafrost';
+ *
+ * $rsa->loadKey($privatekey);
+ * $signature = $rsa->sign($plaintext);
+ *
+ * $rsa->loadKey($publickey);
+ * echo $rsa->verify($plaintext, $signature) ? 'verified' : 'unverified';
+ * ?>
+ * </code>
+ *
+ * LICENSE: This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ *
+ * @category Crypt
+ * @package Crypt_RSA
+ * @author Jim Wigginton <terrafrost@php.net>
+ * @copyright MMIX Jim Wigginton
+ * @license http://www.gnu.org/licenses/lgpl.txt
+ * @version $Id: RSA.php,v 1.15 2010/04/10 15:57:02 terrafrost Exp $
+ * @link http://phpseclib.sourceforge.net
+ */
+
+/**
+ * Include Math_BigInteger
+ */
+require_once('Math/BigInteger.php');
+
+/**
+ * Include Crypt_Random
+ */
+require_once('Crypt/Random.php');
+
+/**
+ * Include Crypt_Hash
+ */
+require_once('Crypt/Hash.php');
+
+/**#@+
+ * @access public
+ * @see Crypt_RSA::encrypt()
+ * @see Crypt_RSA::decrypt()
+ */
+/**
+ * Use {@link http://en.wikipedia.org/wiki/Optimal_Asymmetric_Encryption_Padding Optimal Asymmetric Encryption Padding}
+ * (OAEP) for encryption / decryption.
+ *
+ * Uses sha1 by default.
+ *
+ * @see Crypt_RSA::setHash()
+ * @see Crypt_RSA::setMGFHash()
+ */
+define('CRYPT_RSA_ENCRYPTION_OAEP', 1);
+/**
+ * Use PKCS#1 padding.
+ *
+ * Although CRYPT_RSA_ENCRYPTION_OAEP offers more security, including PKCS#1 padding is necessary for purposes of backwards
+ * compatability with protocols (like SSH-1) written before OAEP's introduction.
+ */
+define('CRYPT_RSA_ENCRYPTION_PKCS1', 2);
+/**#@-*/
+
+/**#@+
+ * @access public
+ * @see Crypt_RSA::sign()
+ * @see Crypt_RSA::verify()
+ * @see Crypt_RSA::setHash()
+ */
+/**
+ * Use the Probabilistic Signature Scheme for signing
+ *
+ * Uses sha1 by default.
+ *
+ * @see Crypt_RSA::setSaltLength()
+ * @see Crypt_RSA::setMGFHash()
+ */
+define('CRYPT_RSA_SIGNATURE_PSS', 1);
+/**
+ * Use the PKCS#1 scheme by default.
+ *
+ * Although CRYPT_RSA_SIGNATURE_PSS offers more security, including PKCS#1 signing is necessary for purposes of backwards
+ * compatability with protocols (like SSH-2) written before PSS's introduction.
+ */
+define('CRYPT_RSA_SIGNATURE_PKCS1', 2);
+/**#@-*/
+
+/**#@+
+ * @access private
+ * @see Crypt_RSA::createKey()
+ */
+/**
+ * ASN1 Integer
+ */
+define('CRYPT_RSA_ASN1_INTEGER', 2);
+/**
+ * ASN1 Sequence (with the constucted bit set)
+ */
+define('CRYPT_RSA_ASN1_SEQUENCE', 48);
+/**#@-*/
+
+/**#@+
+ * @access private
+ * @see Crypt_RSA::Crypt_RSA()
+ */
+/**
+ * To use the pure-PHP implementation
+ */
+define('CRYPT_RSA_MODE_INTERNAL', 1);
+/**
+ * To use the OpenSSL library
+ *
+ * (if enabled; otherwise, the internal implementation will be used)
+ */
+define('CRYPT_RSA_MODE_OPENSSL', 2);
+/**#@-*/
+
+/**#@+
+ * @access public
+ * @see Crypt_RSA::createKey()
+ * @see Crypt_RSA::setPrivateKeyFormat()
+ */
+/**
+ * PKCS#1 formatted private key
+ *
+ * Used by OpenSSH
+ */
+define('CRYPT_RSA_PRIVATE_FORMAT_PKCS1', 0);
+/**#@-*/
+
+/**#@+
+ * @access public
+ * @see Crypt_RSA::createKey()
+ * @see Crypt_RSA::setPublicKeyFormat()
+ */
+/**
+ * Raw public key
+ *
+ * An array containing two Math_BigInteger objects.
+ *
+ * The exponent can be indexed with any of the following:
+ *
+ * 0, e, exponent, publicExponent
+ *
+ * The modulus can be indexed with any of the following:
+ *
+ * 1, n, modulo, modulus
+ */
+define('CRYPT_RSA_PUBLIC_FORMAT_RAW', 1);
+/**
+ * PKCS#1 formatted public key
+ */
+define('CRYPT_RSA_PUBLIC_FORMAT_PKCS1', 2);
+/**
+ * OpenSSH formatted public key
+ *
+ * Place in $HOME/.ssh/authorized_keys
+ */
+define('CRYPT_RSA_PUBLIC_FORMAT_OPENSSH', 3);
+/**#@-*/
+
+/**
+ * Pure-PHP PKCS#1 compliant implementation of RSA.
+ *
+ * @author Jim Wigginton <terrafrost@php.net>
+ * @version 0.1.0
+ * @access public
+ * @package Crypt_RSA
+ */
+class Crypt_RSA {
+ /**
+ * Precomputed Zero
+ *
+ * @var Array
+ * @access private
+ */
+ var $zero;
+
+ /**
+ * Precomputed One
+ *
+ * @var Array
+ * @access private
+ */
+ var $one;
+
+ /**
+ * Private Key Format
+ *
+ * @var Integer
+ * @access private
+ */
+ var $privateKeyFormat = CRYPT_RSA_PRIVATE_FORMAT_PKCS1;
+
+ /**
+ * Public Key Format
+ *
+ * @var Integer
+ * @access public
+ */
+ var $publicKeyFormat = CRYPT_RSA_PUBLIC_FORMAT_PKCS1;
+
+ /**
+ * Modulus (ie. n)
+ *
+ * @var Math_BigInteger
+ * @access private
+ */
+ var $modulus;
+
+ /**
+ * Modulus length
+ *
+ * @var Math_BigInteger
+ * @access private
+ */
+ var $k;
+
+ /**
+ * Exponent (ie. e or d)
+ *
+ * @var Math_BigInteger
+ * @access private
+ */
+ var $exponent;
+
+ /**
+ * Primes for Chinese Remainder Theorem (ie. p and q)
+ *
+ * @var Array
+ * @access private
+ */
+ var $primes;
+
+ /**
+ * Exponents for Chinese Remainder Theorem (ie. dP and dQ)
+ *
+ * @var Array
+ * @access private
+ */
+ var $exponents;
+
+ /**
+ * Coefficients for Chinese Remainder Theorem (ie. qInv)
+ *
+ * @var Array
+ * @access private
+ */
+ var $coefficients;
+
+ /**
+ * Hash name
+ *
+ * @var String
+ * @access private
+ */
+ var $hashName;
+
+ /**
+ * Hash function
+ *
+ * @var Crypt_Hash
+ * @access private
+ */
+ var $hash;
+
+ /**
+ * Length of hash function output
+ *
+ * @var Integer
+ * @access private
+ */
+ var $hLen;
+
+ /**
+ * Length of salt
+ *
+ * @var Integer
+ * @access private
+ */
+ var $sLen;
+
+ /**
+ * Hash function for the Mask Generation Function
+ *
+ * @var Crypt_Hash
+ * @access private
+ */
+ var $mgfHash;
+
+ /**
+ * Length of MGF hash function output
+ *
+ * @var Integer
+ * @access private
+ */
+ var $mgfHLen;
+
+ /**
+ * Encryption mode
+ *
+ * @var Integer
+ * @access private
+ */
+ var $encryptionMode = CRYPT_RSA_ENCRYPTION_OAEP;
+
+ /**
+ * Signature mode
+ *
+ * @var Integer
+ * @access private
+ */
+ var $signatureMode = CRYPT_RSA_SIGNATURE_PSS;
+
+ /**
+ * Public Exponent
+ *
+ * @var Mixed
+ * @access private
+ */
+ var $publicExponent = false;
+
+ /**
+ * Password
+ *
+ * @var String
+ * @access private
+ */
+ var $password = '';
+
+ /**
+ * The constructor
+ *
+ * If you want to make use of the openssl extension, you'll need to set the mode manually, yourself. The reason
+ * Crypt_RSA doesn't do it is because OpenSSL doesn't fail gracefully. openssl_pkey_new(), in particular, requires
+ * openssl.cnf be present somewhere and, unfortunately, the only real way to find out is too late.
+ *
+ * @return Crypt_RSA
+ * @access public
+ */
+ function Crypt_RSA()
+ {
+ if ( !defined('CRYPT_RSA_MODE') ) {
+ switch (true) {
+ //case extension_loaded('openssl') && version_compare(PHP_VERSION, '4.2.0', '>='):
+ // define('CRYPT_RSA_MODE', CRYPT_RSA_MODE_OPENSSL);
+ // break;
+ default:
+ define('CRYPT_RSA_MODE', CRYPT_RSA_MODE_INTERNAL);
+ }
+ }
+
+ $this->zero = new Math_BigInteger();
+ $this->one = new Math_BigInteger(1);
+
+ $this->hash = new Crypt_Hash('sha1');
+ $this->hLen = $this->hash->getLength();
+ $this->hashName = 'sha1';
+ $this->mgfHash = new Crypt_Hash('sha1');
+ $this->mgfHLen = $this->mgfHash->getLength();
+ }
+
+ /**
+ * Create public / private key pair
+ *
+ * Returns an array with the following three elements:
+ * - 'privatekey': The private key.
+ * - 'publickey': The public key.
+ * - 'partialkey': A partially computed key (if the execution time exceeded $timeout).
+ * Will need to be passed back to Crypt_RSA::createKey() as the third parameter for further processing.
+ *
+ * @access public
+ * @param optional Integer $bits
+ * @param optional Integer $timeout
+ * @param optional Math_BigInteger $p
+ */
+ function createKey($bits = 1024, $timeout = false, $partial = array())
+ {
+ if ( CRYPT_RSA_MODE == CRYPT_RSA_MODE_OPENSSL ) {
+ $rsa = openssl_pkey_new(array('private_key_bits' => $bits));
+ openssl_pkey_export($rsa, $privatekey);
+ $publickey = openssl_pkey_get_details($rsa);
+ $publickey = $publickey['key'];
+
+ if ($this->privateKeyFormat != CRYPT_RSA_PRIVATE_FORMAT_PKCS1) {
+ $privatekey = call_user_func_array(array($this, '_convertPrivateKey'), array_values($this->_parseKey($privatekey, CRYPT_RSA_PRIVATE_FORMAT_PKCS1)));
+ $publickey = call_user_func_array(array($this, '_convertPublicKey'), array_values($this->_parseKey($publickey, CRYPT_RSA_PUBLIC_FORMAT_PKCS1)));
+ }
+
+ return array(
+ 'privatekey' => $privatekey,
+ 'publickey' => $publickey,
+ 'partialkey' => false
+ );
+ }
+
+ static $e;
+ if (!isset($e)) {
+ if (!defined('CRYPT_RSA_EXPONENT')) {
+ // http://en.wikipedia.org/wiki/65537_%28number%29
+ define('CRYPT_RSA_EXPONENT', '65537');
+ }
+ if (!defined('CRYPT_RSA_COMMENT')) {
+ define('CRYPT_RSA_COMMENT', 'phpseclib-generated-key');
+ }
+ // per <http://cseweb.ucsd.edu/~hovav/dist/survey.pdf#page=5>, this number ought not result in primes smaller
+ // than 256 bits.
+ if (!defined('CRYPT_RSA_SMALLEST_PRIME')) {
+ define('CRYPT_RSA_SMALLEST_PRIME', 4096);
+ }
+
+ $e = new Math_BigInteger(CRYPT_RSA_EXPONENT);
+ }
+
+ extract($this->_generateMinMax($bits));
+ $absoluteMin = $min;
+ $temp = $bits >> 1;
+ if ($temp > CRYPT_RSA_SMALLEST_PRIME) {
+ $num_primes = floor($bits / CRYPT_RSA_SMALLEST_PRIME);
+ $temp = CRYPT_RSA_SMALLEST_PRIME;
+ } else {
+ $num_primes = 2;
+ }
+ extract($this->_generateMinMax($temp + $bits % $temp));
+ $finalMax = $max;
+ extract($this->_generateMinMax($temp));
+
+ $generator = new Math_BigInteger();
+ $generator->setRandomGenerator('crypt_random');
+
+ $n = $this->one->copy();
+ if (!empty($partial)) {
+ extract(unserialize($partial));
+ } else {
+ $exponents = $coefficients = $primes = array();
+ $lcm = array(
+ 'top' => $this->one->copy(),
+ 'bottom' => false
+ );
+ }
+
+ $start = time();
+ $i0 = count($primes) + 1;
+
+ do {
+ for ($i = $i0; $i <= $num_primes; $i++) {
+ if ($timeout !== false) {
+ $timeout-= time() - $start;
+ $start = time();
+ if ($timeout <= 0) {
+ return serialize(array(
+ 'privatekey' => '',
+ 'publickey' => '',
+ 'partialkey' => array(
+ 'primes' => $primes,
+ 'coefficients' => $coefficients,
+ 'lcm' => $lcm,
+ 'exponents' => $exponents
+ )
+ ));
+ }
+ }
+
+ if ($i == $num_primes) {
+ list($min, $temp) = $absoluteMin->divide($n);
+ if (!$temp->equals($this->zero)) {
+ $min = $min->add($this->one); // ie. ceil()
+ }
+ $primes[$i] = $generator->randomPrime($min, $finalMax, $timeout);
+ } else {
+ $primes[$i] = $generator->randomPrime($min, $max, $timeout);
+ }
+
+ if ($primes[$i] === false) { // if we've reached the timeout
+ return array(
+ 'privatekey' => '',
+ 'publickey' => '',
+ 'partialkey' => empty($primes) ? '' : serialize(array(
+ 'primes' => array_slice($primes, 0, $i - 1),
+ 'coefficients' => $coefficients,
+ 'lcm' => $lcm,
+ 'exponents' => $exponents
+ ))
+ );
+ }
+
+ // the first coefficient is calculated differently from the rest
+ // ie. instead of being $primes[1]->modInverse($primes[2]), it's $primes[2]->modInverse($primes[1])
+ if ($i > 2) {
+ $coefficients[$i] = $n->modInverse($primes[$i]);
+ }
+
+ $n = $n->multiply($primes[$i]);
+
+ $temp = $primes[$i]->subtract($this->one);
+
+ // textbook RSA implementations use Euler's totient function instead of the least common multiple.
+ // see http://en.wikipedia.org/wiki/Euler%27s_totient_function
+ $lcm['top'] = $lcm['top']->multiply($temp);
+ $lcm['bottom'] = $lcm['bottom'] === false ? $temp : $lcm['bottom']->gcd($temp);
+
+ $exponents[$i] = $e->modInverse($temp);
+ }
+
+ list($lcm) = $lcm['top']->divide($lcm['bottom']);
+ $gcd = $lcm->gcd($e);
+ $i0 = 1;
+ } while (!$gcd->equals($this->one));
+
+ $d = $e->modInverse($lcm);
+
+ $coefficients[2] = $primes[2]->modInverse($primes[1]);
+
+ // from <http://tools.ietf.org/html/rfc3447#appendix-A.1.2>:
+ // RSAPrivateKey ::= SEQUENCE {
+ // version Version,
+ // modulus INTEGER, -- n
+ // publicExponent INTEGER, -- e
+ // privateExponent INTEGER, -- d
+ // prime1 INTEGER, -- p
+ // prime2 INTEGER, -- q
+ // exponent1 INTEGER, -- d mod (p-1)
+ // exponent2 INTEGER, -- d mod (q-1)
+ // coefficient INTEGER, -- (inverse of q) mod p
+ // otherPrimeInfos OtherPrimeInfos OPTIONAL
+ // }
+
+ return array(
+ 'privatekey' => $this->_convertPrivateKey($n, $e, $d, $primes, $exponents, $coefficients),
+ 'publickey' => $this->_convertPublicKey($n, $e),
+ 'partialkey' => false
+ );
+ }
+
+ /**
+ * Convert a private key to the appropriate format.
+ *
+ * @access private
+ * @see setPrivateKeyFormat()
+ * @param String $RSAPrivateKey
+ * @return String
+ */
+ function _convertPrivateKey($n, $e, $d, $primes, $exponents, $coefficients)
+ {
+ $num_primes = count($primes);
+ $raw = array(
+ 'version' => $num_primes == 2 ? chr(0) : chr(1), // two-prime vs. multi
+ 'modulus' => $n->toBytes(true),
+ 'publicExponent' => $e->toBytes(true),
+ 'privateExponent' => $d->toBytes(true),
+ 'prime1' => $primes[1]->toBytes(true),
+ 'prime2' => $primes[2]->toBytes(true),
+ 'exponent1' => $exponents[1]->toBytes(true),
+ 'exponent2' => $exponents[2]->toBytes(true),
+ 'coefficient' => $coefficients[2]->toBytes(true)
+ );
+
+ // if the format in question does not support multi-prime rsa and multi-prime rsa was used,
+ // call _convertPublicKey() instead.
+ switch ($this->privateKeyFormat) {
+ default: // eg. CRYPT_RSA_PRIVATE_FORMAT_PKCS1
+ $components = array();
+ foreach ($raw as $name => $value) {
+ $components[$name] = pack('Ca*a*', CRYPT_RSA_ASN1_INTEGER, $this->_encodeLength(strlen($value)), $value);
+ }
+
+ $RSAPrivateKey = implode('', $components);
+
+ if ($num_primes > 2) {
+ $OtherPrimeInfos = '';
+ for ($i = 3; $i <= $num_primes; $i++) {
+ // OtherPrimeInfos ::= SEQUENCE SIZE(1..MAX) OF OtherPrimeInfo
+ //
+ // OtherPrimeInfo ::= SEQUENCE {
+ // prime INTEGER, -- ri
+ // exponent INTEGER, -- di
+ // coefficient INTEGER -- ti
+ // }
+ $OtherPrimeInfo = pack('Ca*a*', CRYPT_RSA_ASN1_INTEGER, $this->_encodeLength(strlen($primes[$i]->toBytes(true))), $primes[$i]->toBytes(true));
+ $OtherPrimeInfo.= pack('Ca*a*', CRYPT_RSA_ASN1_INTEGER, $this->_encodeLength(strlen($exponents[$i]->toBytes(true))), $exponents[$i]->toBytes(true));
+ $OtherPrimeInfo.= pack('Ca*a*', CRYPT_RSA_ASN1_INTEGER, $this->_encodeLength(strlen($coefficients[$i]->toBytes(true))), $coefficients[$i]->toBytes(true));
+ $OtherPrimeInfos.= pack('Ca*a*', CRYPT_RSA_ASN1_SEQUENCE, $this->_encodeLength(strlen($OtherPrimeInfo)), $OtherPrimeInfo);
+ }
+ $RSAPrivateKey.= pack('Ca*a*', CRYPT_RSA_ASN1_SEQUENCE, $this->_encodeLength(strlen($OtherPrimeInfos)), $OtherPrimeInfos);
+ }
+
+ $RSAPrivateKey = pack('Ca*a*', CRYPT_RSA_ASN1_SEQUENCE, $this->_encodeLength(strlen($RSAPrivateKey)), $RSAPrivateKey);
+
+ if (!empty($this->password)) {
+ $iv = $this->_random(8);
+ $symkey = pack('H*', md5($this->password . $iv)); // symkey is short for symmetric key
+ $symkey.= substr(pack('H*', md5($symkey . $this->password . $iv)), 0, 8);
+ if (!class_exists('Crypt_TripleDES')) {
+ require_once('Crypt/TripleDES.php');
+ }
+ $des = new Crypt_TripleDES();
+ $des->setKey($symkey);
+ $des->setIV($iv);
+ $iv = strtoupper(bin2hex($iv));
+ $RSAPrivateKey = "-----BEGIN RSA PRIVATE KEY-----\r\n" .
+ "Proc-Type: 4,ENCRYPTED\r\n" .
+ "DEK-Info: DES-EDE3-CBC,$iv\r\n" .
+ "\r\n" .
+ chunk_split(base64_encode($des->encrypt($RSAPrivateKey))) .
+ '-----END RSA PRIVATE KEY-----';
+ } else {
+ $RSAPrivateKey = "-----BEGIN RSA PRIVATE KEY-----\r\n" .
+ chunk_split(base64_encode($RSAPrivateKey)) .
+ '-----END RSA PRIVATE KEY-----';
+ }
+
+ return $RSAPrivateKey;
+ }
+ }
+
+ /**
+ * Convert a public key to the appropriate format
+ *
+ * @access private
+ * @see setPublicKeyFormat()
+ * @param String $RSAPrivateKey
+ * @return String
+ */
+ function _convertPublicKey($n, $e)
+ {
+ $modulus = $n->toBytes(true);
+ $publicExponent = $e->toBytes(true);
+
+ switch ($this->publicKeyFormat) {
+ case CRYPT_RSA_PUBLIC_FORMAT_RAW:
+ return array('e' => $e->copy(), 'n' => $n->copy());
+ case CRYPT_RSA_PUBLIC_FORMAT_OPENSSH:
+ // from <http://tools.ietf.org/html/rfc4253#page-15>:
+ // string "ssh-rsa"
+ // mpint e
+ // mpint n
+ $RSAPublicKey = pack('Na*Na*Na*', strlen('ssh-rsa'), 'ssh-rsa', strlen($publicExponent), $publicExponent, strlen($modulus), $modulus);
+ $RSAPublicKey = 'ssh-rsa ' . base64_encode($RSAPublicKey) . ' ' . CRYPT_RSA_COMMENT;
+
+ return $RSAPublicKey;
+ default: // eg. CRYPT_RSA_PUBLIC_FORMAT_PKCS1
+ // from <http://tools.ietf.org/html/rfc3447#appendix-A.1.1>:
+ // RSAPublicKey ::= SEQUENCE {
+ // modulus INTEGER, -- n
+ // publicExponent INTEGER -- e
+ // }
+ $components = array(
+ 'modulus' => pack('Ca*a*', CRYPT_RSA_ASN1_INTEGER, $this->_encodeLength(strlen($modulus)), $modulus),
+ 'publicExponent' => pack('Ca*a*', CRYPT_RSA_ASN1_INTEGER, $this->_encodeLength(strlen($publicExponent)), $publicExponent)
+ );
+
+ $RSAPublicKey = pack('Ca*a*a*',
+ CRYPT_RSA_ASN1_SEQUENCE, $this->_encodeLength(strlen($components['modulus']) + strlen($components['publicExponent'])),
+ $components['modulus'], $components['publicExponent']
+ );
+
+ $RSAPublicKey = "-----BEGIN PUBLIC KEY-----\r\n" .
+ chunk_split(base64_encode($RSAPublicKey)) .
+ '-----END PUBLIC KEY-----';
+
+ return $RSAPublicKey;
+ }
+ }
+
+ /**
+ * Break a public or private key down into its constituant components
+ *
+ * @access private
+ * @see _convertPublicKey()
+ * @see _convertPrivateKey()
+ * @param String $key
+ * @param Integer $type
+ * @return Array
+ */
+ function _parseKey($key, $type)
+ {
+ switch ($type) {
+ case CRYPT_RSA_PUBLIC_FORMAT_RAW:
+ if (!is_array($key)) {
+ return false;
+ }
+ $components = array();
+ switch (true) {
+ case isset($key['e']):
+ $components['publicExponent'] = $key['e']->copy();
+ break;
+ case isset($key['exponent']):
+ $components['publicExponent'] = $key['exponent']->copy();
+ break;
+ case isset($key['publicExponent']):
+ $components['publicExponent'] = $key['publicExponent']->copy();
+ break;
+ case isset($key[0]):
+ $components['publicExponent'] = $key[0]->copy();
+ }
+ switch (true) {
+ case isset($key['n']):
+ $components['modulus'] = $key['n']->copy();
+ break;
+ case isset($key['modulo']):
+ $components['modulus'] = $key['modulo']->copy();
+ break;
+ case isset($key['modulus']):
+ $components['modulus'] = $key['modulus']->copy();
+ break;
+ case isset($key[1]):
+ $components['modulus'] = $key[1]->copy();
+ }
+ return $components;
+ case CRYPT_RSA_PRIVATE_FORMAT_PKCS1:
+ case CRYPT_RSA_PUBLIC_FORMAT_PKCS1:
+ /* Although PKCS#1 proposes a format that public and private keys can use, encrypting them is
+ "outside the scope" of PKCS#1. PKCS#1 then refers you to PKCS#12 and PKCS#15 if you're wanting to
+ protect private keys, however, that's not what OpenSSL* does. OpenSSL protects private keys by adding
+ two new "fields" to the key - DEK-Info and Proc-Type. These fields are discussed here:
+
+ http://tools.ietf.org/html/rfc1421#section-4.6.1.1
+ http://tools.ietf.org/html/rfc1421#section-4.6.1.3
+
+ DES-EDE3-CBC as an algorithm, however, is not discussed anywhere, near as I can tell.
+ DES-CBC and DES-EDE are discussed in RFC1423, however, DES-EDE3-CBC isn't, nor is its key derivation
+ function. As is, the definitive authority on this encoding scheme isn't the IETF but rather OpenSSL's
+ own implementation. ie. the implementation *is* the standard and any bugs that may exist in that
+ implementation are part of the standard, as well.
+
+ * OpenSSL is the de facto standard. It's utilized by OpenSSH and other projects */
+ if (preg_match('#DEK-Info: (.+),(.+)#', $key, $matches)) {
+ $iv = pack('H*', trim($matches[2]));
+ $symkey = pack('H*', md5($this->password . $iv)); // symkey is short for symmetric key
+ $symkey.= substr(pack('H*', md5($symkey . $this->password . $iv)), 0, 8);
+ $ciphertext = preg_replace('#.+(\r|\n|\r\n)\1|[\r\n]|-.+-#s', '', $key);
+ $ciphertext = preg_match('#^[a-zA-Z\d/+]*={0,2}$#', $ciphertext) ? base64_decode($ciphertext) : false;
+ if ($ciphertext === false) {
+ $ciphertext = $key;
+ }
+ switch ($matches[1]) {
+ case 'DES-EDE3-CBC':
+ if (!class_exists('Crypt_TripleDES')) {
+ require_once('Crypt/TripleDES.php');
+ }
+ $crypto = new Crypt_TripleDES();
+ break;
+ case 'DES-CBC':
+ if (!class_exists('Crypt_DES')) {
+ require_once('Crypt/DES.php');
+ }
+ $crypto = new Crypt_DES();
+ break;
+ default:
+ return false;
+ }
+ $crypto->setKey($symkey);
+ $crypto->setIV($iv);
+ $decoded = $crypto->decrypt($ciphertext);
+ } else {
+ $decoded = preg_replace('#-.+-|[\r\n]#', '', $key);
+ $decoded = preg_match('#^[a-zA-Z\d/+]*={0,2}$#', $decoded) ? base64_decode($decoded) : false;
+ }
+
+ if ($decoded !== false) {
+ $key = $decoded;
+ }
+
+ $components = array();
+
+ if (ord($this->_string_shift($key)) != CRYPT_RSA_ASN1_SEQUENCE) {
+ return false;
+ }
+ if ($this->_decodeLength($key) != strlen($key)) {
+ return false;
+ }
+
+ $tag = ord($this->_string_shift($key));
+ if ($tag == CRYPT_RSA_ASN1_SEQUENCE) {
+ /* intended for keys for which OpenSSL's asn1parse returns the following:
+
+ 0:d=0 hl=4 l= 290 cons: SEQUENCE
+ 4:d=1 hl=2 l= 13 cons: SEQUENCE
+ 6:d=2 hl=2 l= 9 prim: OBJECT :rsaEncryption
+ 17:d=2 hl=2 l= 0 prim: NULL
+ 19:d=1 hl=4 l= 271 prim: BIT STRING */
+ $this->_string_shift($key, $this->_decodeLength($key));
+ $this->_string_shift($key); // skip over the BIT STRING tag
+ $this->_decodeLength($key); // skip over the BIT STRING length
+ // "The initial octet shall encode, as an unsigned binary integer wtih bit 1 as the least significant bit, the number of
+ // unused bits in teh final subsequent octet. The number shall be in the range zero to seven."
+ // -- http://www.itu.int/ITU-T/studygroups/com17/languages/X.690-0207.pdf (section 8.6.2.2)
+ $this->_string_shift($key);
+ if (ord($this->_string_shift($key)) != CRYPT_RSA_ASN1_SEQUENCE) {
+ return false;
+ }
+ if ($this->_decodeLength($key) != strlen($key)) {
+ return false;
+ }
+ $tag = ord($this->_string_shift($key));
+ }
+ if ($tag != CRYPT_RSA_ASN1_INTEGER) {
+ return false;
+ }
+
+ $length = $this->_decodeLength($key);
+ $temp = $this->_string_shift($key, $length);
+ if (strlen($temp) != 1 || ord($temp) > 2) {
+ $components['modulus'] = new Math_BigInteger($temp, -256);
+ $this->_string_shift($key); // skip over CRYPT_RSA_ASN1_INTEGER
+ $length = $this->_decodeLength($key);
+ $components[$type == CRYPT_RSA_PUBLIC_FORMAT_PKCS1 ? 'publicExponent' : 'privateExponent'] = new Math_BigInteger($this->_string_shift($key, $length), -256);
+
+ return $components;
+ }
+ if (ord($this->_string_shift($key)) != CRYPT_RSA_ASN1_INTEGER) {
+ return false;
+ }
+ $length = $this->_decodeLength($key);
+ $components['modulus'] = new Math_BigInteger($this->_string_shift($key, $length), -256);
+ $this->_string_shift($key);
+ $length = $this->_decodeLength($key);
+ $components['publicExponent'] = new Math_BigInteger($this->_string_shift($key, $length), -256);
+ $this->_string_shift($key);
+ $length = $this->_decodeLength($key);
+ $components['privateExponent'] = new Math_BigInteger($this->_string_shift($key, $length), -256);
+ $this->_string_shift($key);
+ $length = $this->_decodeLength($key);
+ $components['primes'] = array(1 => new Math_BigInteger($this->_string_shift($key, $length), -256));
+ $this->_string_shift($key);
+ $length = $this->_decodeLength($key);
+ $components['primes'][] = new Math_BigInteger($this->_string_shift($key, $length), -256);
+ $this->_string_shift($key);
+ $length = $this->_decodeLength($key);
+ $components['exponents'] = array(1 => new Math_BigInteger($this->_string_shift($key, $length), -256));
+ $this->_string_shift($key);
+ $length = $this->_decodeLength($key);
+ $components['exponents'][] = new Math_BigInteger($this->_string_shift($key, $length), -256);
+ $this->_string_shift($key);
+ $length = $this->_decodeLength($key);
+ $components['coefficients'] = array(2 => new Math_BigInteger($this->_string_shift($key, $length), -256));
+
+ if (!empty($key)) {
+ if (ord($this->_string_shift($key)) != CRYPT_RSA_ASN1_SEQUENCE) {
+ return false;
+ }
+ $this->_decodeLength($key);
+ while (!empty($key)) {
+ if (ord($this->_string_shift($key)) != CRYPT_RSA_ASN1_SEQUENCE) {
+ return false;
+ }
+ $this->_decodeLength($key);
+ $key = substr($key, 1);
+ $length = $this->_decodeLength($key);
+ $components['primes'][] = new Math_BigInteger($this->_string_shift($key, $length), -256);
+ $this->_string_shift($key);
+ $length = $this->_decodeLength($key);
+ $components['exponents'][] = new Math_BigInteger($this->_string_shift($key, $length), -256);
+ $this->_string_shift($key);
+ $length = $this->_decodeLength($key);
+ $components['coefficients'][] = new Math_BigInteger($this->_string_shift($key, $length), -256);
+ }
+ }
+
+ return $components;
+ case CRYPT_RSA_PUBLIC_FORMAT_OPENSSH:
+ $key = base64_decode(preg_replace('#^ssh-rsa | .+$#', '', $key));
+ if ($key === false) {
+ return false;
+ }
+
+ $cleanup = substr($key, 0, 11) == "\0\0\0\7ssh-rsa";
+
+ extract(unpack('Nlength', $this->_string_shift($key, 4)));
+ $publicExponent = new Math_BigInteger($this->_string_shift($key, $length), -256);
+ extract(unpack('Nlength', $this->_string_shift($key, 4)));
+ $modulus = new Math_BigInteger($this->_string_shift($key, $length), -256);
+
+ if ($cleanup && strlen($key)) {
+ extract(unpack('Nlength', $this->_string_shift($key, 4)));
+ return array(
+ 'modulus' => new Math_BigInteger($this->_string_shift($key, $length), -256),
+ 'publicExponent' => $modulus
+ );
+ } else {
+ return array(
+ 'modulus' => $modulus,
+ 'publicExponent' => $publicExponent
+ );
+ }
+ }
+ }
+
+ /**
+ * Loads a public or private key
+ *
+ * Returns true on success and false on failure (ie. an incorrect password was provided or the key was malformed)
+ *
+ * @access public
+ * @param String $key
+ * @param Integer $type optional
+ */
+ function loadKey($key, $type = CRYPT_RSA_PRIVATE_FORMAT_PKCS1)
+ {
+ $components = $this->_parseKey($key, $type);
+ if ($components === false) {
+ return false;
+ }
+
+ $this->modulus = $components['modulus'];
+ $this->k = strlen($this->modulus->toBytes());
+ $this->exponent = isset($components['privateExponent']) ? $components['privateExponent'] : $components['publicExponent'];
+ if (isset($components['primes'])) {
+ $this->primes = $components['primes'];
+ $this->exponents = $components['exponents'];
+ $this->coefficients = $components['coefficients'];
+ $this->publicExponent = $components['publicExponent'];
+ } else {
+ $this->primes = array();
+ $this->exponents = array();
+ $this->coefficients = array();
+ $this->publicExponent = false;
+ }
+
+ return true;
+ }
+
+ /**
+ * 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 true.
+ *
+ * @see createKey()
+ * @see loadKey()
+ * @access public
+ * @param String $password
+ */
+ function setPassword($password)
+ {
+ $this->password = $password;
+ }
+
+ /**
+ * Defines the public key
+ *
+ * Some private key formats define the public exponent and some don't. Those that don't define it are problematic when
+ * used in certain contexts. For example, in SSH-2, RSA authentication works by sending the public key along with a
+ * message signed by the private key to the server. The SSH-2 server looks the public key up in an index of public keys
+ * and if it's present then proceeds to verify the signature. Problem is, if your private key doesn't include the public
+ * exponent this won't work unless you manually add the public exponent.
+ *
+ * Do note that when a new key is loaded the index will be cleared.
+ *
+ * Returns true on success, false on failure
+ *
+ * @see getPublicKey()
+ * @access public
+ * @param String $key
+ * @param Integer $type optional
+ * @return Boolean
+ */
+ function setPublicKey($key, $type = CRYPT_RSA_PUBLIC_FORMAT_PKCS1)
+ {
+ $components = $this->_parseKey($key, $type);
+ if (empty($this->modulus) || !$this->modulus->equals($components['modulus'])) {
+ return false;
+ }
+ $this->publicExponent = $components['publicExponent'];
+ }
+
+ /**
+ * Returns the public key
+ *
+ * The public key is only returned under two circumstances - if the private key had the public key embedded within it
+ * or if the public key was set via setPublicKey(). If the currently loaded key is supposed to be the public key this
+ * function won't return it since this library, for the most part, doesn't distinguish between public and private keys.
+ *
+ * @see getPublicKey()
+ * @access public
+ * @param String $key
+ * @param Integer $type optional
+ */
+ function getPublicKey($type = CRYPT_RSA_PUBLIC_FORMAT_PKCS1)
+ {
+ if (empty($this->modulus) || empty($this->publicExponent)) {
+ return false;
+ }
+
+ $oldFormat = $this->publicKeyFormat;
+ $this->publicKeyFormat = $type;
+ $temp = $this->_convertPublicKey($this->modulus, $this->publicExponent);
+ $this->publicKeyFormat = $oldFormat;
+ return $temp;
+ }
+
+ /**
+ * Generates the smallest and largest numbers requiring $bits bits
+ *
+ * @access private
+ * @param Integer $bits
+ * @return Array
+ */
+ function _generateMinMax($bits)
+ {
+ $bytes = $bits >> 3;
+ $min = str_repeat(chr(0), $bytes);
+ $max = str_repeat(chr(0xFF), $bytes);
+ $msb = $bits & 7;
+ if ($msb) {
+ $min = chr(1 << ($msb - 1)) . $min;
+ $max = chr((1 << $msb) - 1) . $max;
+ } else {
+ $min[0] = chr(0x80);
+ }
+
+ return array(
+ 'min' => new Math_BigInteger($min, 256),
+ 'max' => new Math_BigInteger($max, 256)
+ );
+ }
+
+ /**
+ * DER-decode the length
+ *
+ * DER supports lengths up to (2**8)**127, however, we'll only support lengths up to (2**8)**4. See
+ * {@link http://itu.int/ITU-T/studygroups/com17/languages/X.690-0207.pdf#p=13 X.690 § 8.1.3} for more information.
+ *
+ * @access private
+ * @param String $string
+ * @return Integer
+ */
+ function _decodeLength(&$string)
+ {
+ $length = ord($this->_string_shift($string));
+ if ( $length & 0x80 ) { // definite length, long form
+ $length&= 0x7F;
+ $temp = $this->_string_shift($string, $length);
+ list(, $length) = unpack('N', substr(str_pad($temp, 4, chr(0), STR_PAD_LEFT), -4));
+ }
+ return $length;
+ }
+
+ /**
+ * DER-encode the length
+ *
+ * DER supports lengths up to (2**8)**127, however, we'll only support lengths up to (2**8)**4. See
+ * {@link http://itu.int/ITU-T/studygroups/com17/languages/X.690-0207.pdf#p=13 X.690 § 8.1.3} for more information.
+ *
+ * @access private
+ * @param Integer $length
+ * @return String
+ */
+ function _encodeLength($length)
+ {
+ if ($length <= 0x7F) {
+ return chr($length);
+ }
+
+ $temp = ltrim(pack('N', $length), chr(0));
+ return pack('Ca*', 0x80 | strlen($temp), $temp);
+ }
+
+ /**
+ * String Shift
+ *
+ * Inspired by array_shift
+ *
+ * @param String $string
+ * @param optional Integer $index
+ * @return String
+ * @access private
+ */
+ function _string_shift(&$string, $index = 1)
+ {
+ $substr = substr($string, 0, $index);
+ $string = substr($string, $index);
+ return $substr;
+ }
+
+ /**
+ * Determines the private key format
+ *
+ * @see createKey()
+ * @access public
+ * @param Integer $format
+ */
+ function setPrivateKeyFormat($format)
+ {
+ $this->privateKeyFormat = $format;
+ }
+
+ /**
+ * Determines the public key format
+ *
+ * @see createKey()
+ * @access public
+ * @param Integer $format
+ */
+ function setPublicKeyFormat($format)
+ {
+ $this->publicKeyFormat = $format;
+ }
+
+ /**
+ * Determines which hashing function should be used
+ *
+ * Used with signature production / verification and (if the encryption mode is CRYPT_RSA_ENCRYPTION_OAEP) encryption and
+ * decryption. If $hash isn't supported, sha1 is used.
+ *
+ * @access public
+ * @param String $hash
+ */
+ function setHash($hash)
+ {
+ // Crypt_Hash supports algorithms that PKCS#1 doesn't support. md5-96 and sha1-96, for example.
+ switch ($hash) {
+ case 'md2':
+ case 'md5':
+ case 'sha1':
+ case 'sha256':
+ case 'sha384':
+ case 'sha512':
+ $this->hash = new Crypt_Hash($hash);
+ $this->hashName = $hash;
+ break;
+ default:
+ $this->hash = new Crypt_Hash('sha1');
+ $this->hashName = 'sha1';
+ }
+ $this->hLen = $this->hash->getLength();
+ }
+
+ /**
+ * Determines which hashing function should be used for the mask generation function
+ *
+ * The mask generation function is used by CRYPT_RSA_ENCRYPTION_OAEP and CRYPT_RSA_SIGNATURE_PSS and although it's
+ * best if Hash and MGFHash are set to the same thing this is not a requirement.
+ *
+ * @access public
+ * @param String $hash
+ */
+ function setMGFHash($hash)
+ {
+ // Crypt_Hash supports algorithms that PKCS#1 doesn't support. md5-96 and sha1-96, for example.
+ switch ($hash) {
+ case 'md2':
+ case 'md5':
+ case 'sha1':
+ case 'sha256':
+ case 'sha384':
+ case 'sha512':
+ $this->mgfHash = new Crypt_Hash($hash);
+ break;
+ default:
+ $this->mgfHash = new Crypt_Hash('sha1');
+ }
+ $this->mgfHLen = $this->mgfHash->getLength();
+ }
+
+ /**
+ * Determines the salt length
+ *
+ * To quote from {@link http://tools.ietf.org/html/rfc3447#page-38 RFC3447#page-38}:
+ *
+ * Typical salt lengths in octets are hLen (the length of the output
+ * of the hash function Hash) and 0.
+ *
+ * @access public
+ * @param Integer $format
+ */
+ function setSaltLength($sLen)
+ {
+ $this->sLen = $sLen;
+ }
+
+ /**
+ * Generates a random string x bytes long
+ *
+ * @access public
+ * @param Integer $bytes
+ * @param optional Integer $nonzero
+ * @return String
+ */
+ function _random($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;
+ }
+
+ /**
+ * Integer-to-Octet-String primitive
+ *
+ * See {@link http://tools.ietf.org/html/rfc3447#section-4.1 RFC3447#section-4.1}.
+ *
+ * @access private
+ * @param Math_BigInteger $x
+ * @param Integer $xLen
+ * @return String
+ */
+ function _i2osp($x, $xLen)
+ {
+ $x = $x->toBytes();
+ if (strlen($x) > $xLen) {
+ user_error('Integer too large', E_USER_NOTICE);
+ return false;
+ }
+ return str_pad($x, $xLen, chr(0), STR_PAD_LEFT);
+ }
+
+ /**
+ * Octet-String-to-Integer primitive
+ *
+ * See {@link http://tools.ietf.org/html/rfc3447#section-4.2 RFC3447#section-4.2}.
+ *
+ * @access private
+ * @param String $x
+ * @return Math_BigInteger
+ */
+ function _os2ip($x)
+ {
+ return new Math_BigInteger($x, 256);
+ }
+
+ /**
+ * Exponentiate with or without Chinese Remainder Theorem
+ *
+ * See {@link http://tools.ietf.org/html/rfc3447#section-5.1.1 RFC3447#section-5.1.2}.
+ *
+ * @access private
+ * @param Math_BigInteger $x
+ * @return Math_BigInteger
+ */
+ function _exponentiate($x)
+ {
+ if (empty($this->primes) || empty($this->coefficients) || empty($this->exponents)) {
+ return $x->modPow($this->exponent, $this->modulus);
+ }
+
+ $num_primes = count($this->primes);
+
+ if (defined('CRYPT_RSA_DISABLE_BLINDING')) {
+ $m_i = array(
+ 1 => $x->modPow($this->exponents[1], $this->primes[1]),
+ 2 => $x->modPow($this->exponents[2], $this->primes[2])
+ );
+ $h = $m_i[1]->subtract($m_i[2]);
+ $h = $h->multiply($this->coefficients[2]);
+ list(, $h) = $h->divide($this->primes[1]);
+ $m = $m_i[2]->add($h->multiply($this->primes[2]));
+
+ $r = $this->primes[1];
+ for ($i = 3; $i <= $num_primes; $i++) {
+ $m_i = $x->modPow($this->exponents[$i], $this->primes[$i]);
+
+ $r = $r->multiply($this->primes[$i - 1]);
+
+ $h = $m_i->subtract($m);
+ $h = $h->multiply($this->coefficients[$i]);
+ list(, $h) = $h->divide($this->primes[$i]);
+
+ $m = $m->add($r->multiply($h));
+ }
+ } else {
+ $smallest = $this->primes[1];
+ for ($i = 2; $i <= $num_primes; $i++) {
+ if ($smallest->compare($this->primes[$i]) > 0) {
+ $smallest = $this->primes[$i];
+ }
+ }
+
+ $one = new Math_BigInteger(1);
+ $one->setRandomGenerator('crypt_random');
+
+ $r = $one->random($one, $smallest->subtract($one));
+
+ $m_i = array(
+ 1 => $this->_blind($x, $r, 1),
+ 2 => $this->_blind($x, $r, 2)
+ );
+ $h = $m_i[1]->subtract($m_i[2]);
+ $h = $h->multiply($this->coefficients[2]);
+ list(, $h) = $h->divide($this->primes[1]);
+ $m = $m_i[2]->add($h->multiply($this->primes[2]));
+
+ $r = $this->primes[1];
+ for ($i = 3; $i <= $num_primes; $i++) {
+ $m_i = $this->_blind($x, $r, $i);
+
+ $r = $r->multiply($this->primes[$i - 1]);
+
+ $h = $m_i->subtract($m);
+ $h = $h->multiply($this->coefficients[$i]);
+ list(, $h) = $h->divide($this->primes[$i]);
+
+ $m = $m->add($r->multiply($h));
+ }
+ }
+
+ return $m;
+ }
+
+ /**
+ * Performs RSA Blinding
+ *
+ * Protects against timing attacks by employing RSA Blinding.
+ * Returns $x->modPow($this->exponents[$i], $this->primes[$i])
+ *
+ * @access private
+ * @param Math_BigInteger $x
+ * @param Math_BigInteger $r
+ * @param Integer $i
+ * @return Math_BigInteger
+ */
+ function _blind($x, $r, $i)
+ {
+ $x = $x->multiply($r->modPow($this->publicExponent, $this->primes[$i]));
+
+ $x = $x->modPow($this->exponents[$i], $this->primes[$i]);
+
+ $r = $r->modInverse($this->primes[$i]);
+ $x = $x->multiply($r);
+ list(, $x) = $x->divide($this->primes[$i]);
+
+ return $x;
+ }
+
+ /**
+ * RSAEP
+ *
+ * See {@link http://tools.ietf.org/html/rfc3447#section-5.1.1 RFC3447#section-5.1.1}.
+ *
+ * @access private
+ * @param Math_BigInteger $m
+ * @return Math_BigInteger
+ */
+ function _rsaep($m)
+ {
+ if ($m->compare($this->zero) < 0 || $m->compare($this->modulus) > 0) {
+ user_error('Message representative out of range', E_USER_NOTICE);
+ return false;
+ }
+ return $this->_exponentiate($m);
+ }
+
+ /**
+ * RSADP
+ *
+ * See {@link http://tools.ietf.org/html/rfc3447#section-5.1.2 RFC3447#section-5.1.2}.
+ *
+ * @access private
+ * @param Math_BigInteger $c
+ * @return Math_BigInteger
+ */
+ function _rsadp($c)
+ {
+ if ($c->compare($this->zero) < 0 || $c->compare($this->modulus) > 0) {
+ user_error('Ciphertext representative out of range', E_USER_NOTICE);
+ return false;
+ }
+ return $this->_exponentiate($c);
+ }
+
+ /**
+ * RSASP1
+ *
+ * See {@link http://tools.ietf.org/html/rfc3447#section-5.2.1 RFC3447#section-5.2.1}.
+ *
+ * @access private
+ * @param Math_BigInteger $m
+ * @return Math_BigInteger
+ */
+ function _rsasp1($m)
+ {
+ if ($m->compare($this->zero) < 0 || $m->compare($this->modulus) > 0) {
+ user_error('Message representative out of range', E_USER_NOTICE);
+ return false;
+ }
+ return $this->_exponentiate($m);
+ }
+
+ /**
+ * RSAVP1
+ *
+ * See {@link http://tools.ietf.org/html/rfc3447#section-5.2.2 RFC3447#section-5.2.2}.
+ *
+ * @access private
+ * @param Math_BigInteger $s
+ * @return Math_BigInteger
+ */
+ function _rsavp1($s)
+ {
+ if ($s->compare($this->zero) < 0 || $s->compare($this->modulus) > 0) {
+ user_error('Signature representative out of range', E_USER_NOTICE);
+ return false;
+ }
+ return $this->_exponentiate($s);
+ }
+
+ /**
+ * MGF1
+ *
+ * See {@link http://tools.ietf.org/html/rfc3447#appendix-B.2.1 RFC3447#appendix-B.2.1}.
+ *
+ * @access private
+ * @param String $mgfSeed
+ * @param Integer $mgfLen
+ * @return String
+ */
+ function _mgf1($mgfSeed, $maskLen)
+ {
+ // if $maskLen would yield strings larger than 4GB, PKCS#1 suggests a "Mask too long" error be output.
+
+ $t = '';
+ $count = ceil($maskLen / $this->mgfHLen);
+ for ($i = 0; $i < $count; $i++) {
+ $c = pack('N', $i);
+ $t.= $this->mgfHash->hash($mgfSeed . $c);
+ }
+
+ return substr($t, 0, $maskLen);
+ }
+
+ /**
+ * RSAES-OAEP-ENCRYPT
+ *
+ * See {@link http://tools.ietf.org/html/rfc3447#section-7.1.1 RFC3447#section-7.1.1} and
+ * {http://en.wikipedia.org/wiki/Optimal_Asymmetric_Encryption_Padding OAES}.
+ *
+ * @access private
+ * @param String $m
+ * @param String $l
+ * @return String
+ */
+ function _rsaes_oaep_encrypt($m, $l = '')
+ {
+ $mLen = strlen($m);
+
+ // Length checking
+
+ // if $l is larger than two million terrabytes and you're using sha1, PKCS#1 suggests a "Label too long" error
+ // be output.
+
+ if ($mLen > $this->k - 2 * $this->hLen - 2) {
+ user_error('Message too long', E_USER_NOTICE);
+ return false;
+ }
+
+ // EME-OAEP encoding
+
+ $lHash = $this->hash->hash($l);
+ $ps = str_repeat(chr(0), $this->k - $mLen - 2 * $this->hLen - 2);
+ $db = $lHash . $ps . chr(1) . $m;
+ $seed = $this->_random($this->hLen);
+ $dbMask = $this->_mgf1($seed, $this->k - $this->hLen - 1);
+ $maskedDB = $db ^ $dbMask;
+ $seedMask = $this->_mgf1($maskedDB, $this->hLen);
+ $maskedSeed = $seed ^ $seedMask;
+ $em = chr(0) . $maskedSeed . $maskedDB;
+
+ // RSA encryption
+
+ $m = $this->_os2ip($em);
+ $c = $this->_rsaep($m);
+ $c = $this->_i2osp($c, $this->k);
+
+ // Output the ciphertext C
+
+ return $c;
+ }
+
+ /**
+ * RSAES-OAEP-DECRYPT
+ *
+ * See {@link http://tools.ietf.org/html/rfc3447#section-7.1.2 RFC3447#section-7.1.2}. The fact that the error
+ * messages aren't distinguishable from one another hinders debugging, but, to quote from RFC3447#section-7.1.2:
+ *
+ * Note. Care must be taken to ensure that an opponent cannot
+ * distinguish the different error conditions in Step 3.g, whether by
+ * error message or timing, or, more generally, learn partial
+ * information about the encoded message EM. Otherwise an opponent may
+ * be able to obtain useful information about the decryption of the
+ * ciphertext C, leading to a chosen-ciphertext attack such as the one
+ * observed by Manger [36].
+ *
+ * As for $l... to quote from {@link http://tools.ietf.org/html/rfc3447#page-17 RFC3447#page-17}:
+ *
+ * Both the encryption and the decryption operations of RSAES-OAEP take
+ * the value of a label L as input. In this version of PKCS #1, L is
+ * the empty string; other uses of the label are outside the scope of
+ * this document.
+ *
+ * @access private
+ * @param String $c
+ * @param String $l
+ * @return String
+ */
+ function _rsaes_oaep_decrypt($c, $l = '')
+ {
+ // Length checking
+
+ // if $l is larger than two million terrabytes and you're using sha1, PKCS#1 suggests a "Label too long" error
+ // be output.
+
+ if (strlen($c) != $this->k || $this->k < 2 * $this->hLen + 2) {
+ user_error('Decryption error', E_USER_NOTICE);
+ return false;
+ }
+
+ // RSA decryption
+
+ $c = $this->_os2ip($c);
+ $m = $this->_rsadp($c);
+ if ($m === false) {
+ user_error('Decryption error', E_USER_NOTICE);
+ return false;
+ }
+ $em = $this->_i2osp($m, $this->k);
+
+ // EME-OAEP decoding
+
+ $lHash = $this->hash->hash($l);
+ $y = ord($em[0]);
+ $maskedSeed = substr($em, 1, $this->hLen);
+ $maskedDB = substr($em, $this->hLen + 1);
+ $seedMask = $this->_mgf1($maskedDB, $this->hLen);
+ $seed = $maskedSeed ^ $seedMask;
+ $dbMask = $this->_mgf1($seed, $this->k - $this->hLen - 1);
+ $db = $maskedDB ^ $dbMask;
+ $lHash2 = substr($db, 0, $this->hLen);
+ $m = substr($db, $this->hLen);
+ if ($lHash != $lHash2) {
+ user_error('Decryption error', E_USER_NOTICE);
+ return false;
+ }
+ $m = ltrim($m, chr(0));
+ if (ord($m[0]) != 1) {
+ user_error('Decryption error', E_USER_NOTICE);
+ return false;
+ }
+
+ // Output the message M
+
+ return substr($m, 1);
+ }
+
+ /**
+ * RSAES-PKCS1-V1_5-ENCRYPT
+ *
+ * See {@link http://tools.ietf.org/html/rfc3447#section-7.2.1 RFC3447#section-7.2.1}.
+ *
+ * @access private
+ * @param String $m
+ * @return String
+ */
+ function _rsaes_pkcs1_v1_5_encrypt($m)
+ {
+ $mLen = strlen($m);
+
+ // Length checking
+
+ if ($mLen > $this->k - 11) {
+ user_error('Message too long', E_USER_NOTICE);
+ return false;
+ }
+
+ // EME-PKCS1-v1_5 encoding
+
+ $ps = $this->_random($this->k - $mLen - 3, true);
+ $em = chr(0) . chr(2) . $ps . chr(0) . $m;
+
+ // RSA encryption
+ $m = $this->_os2ip($em);
+ $c = $this->_rsaep($m);
+ $c = $this->_i2osp($c, $this->k);
+
+ // Output the ciphertext C
+
+ return $c;
+ }
+
+ /**
+ * RSAES-PKCS1-V1_5-DECRYPT
+ *
+ * See {@link http://tools.ietf.org/html/rfc3447#section-7.2.2 RFC3447#section-7.2.2}.
+ *
+ * For compatability purposes, this function departs slightly from the description given in RFC3447.
+ * The reason being that RFC2313#section-8.1 (PKCS#1 v1.5) states that ciphertext's encrypted by the
+ * private key should have the second byte set to either 0 or 1 and that ciphertext's encrypted by the
+ * public key should have the second byte set to 2. In RFC3447 (PKCS#1 v2.1), the second byte is supposed
+ * to be 2 regardless of which key is used. for compatability purposes, we'll just check to make sure the
+ * second byte is 2 or less. If it is, we'll accept the decrypted string as valid.
+ *
+ * As a consequence of this, a private key encrypted ciphertext produced with Crypt_RSA may not decrypt
+ * with a strictly PKCS#1 v1.5 compliant RSA implementation. Public key encrypted ciphertext's should but
+ * not private key encrypted ciphertext's.
+ *
+ * @access private
+ * @param String $c
+ * @return String
+ */
+ function _rsaes_pkcs1_v1_5_decrypt($c)
+ {
+ // Length checking
+
+ if (strlen($c) != $this->k) { // or if k < 11
+ user_error('Decryption error', E_USER_NOTICE);
+ return false;
+ }
+
+ // RSA decryption
+
+ $c = $this->_os2ip($c);
+ $m = $this->_rsadp($c);
+ if ($m === false) {
+ user_error('Decryption error', E_USER_NOTICE);
+ return false;
+ }
+ $em = $this->_i2osp($m, $this->k);
+
+ // EME-PKCS1-v1_5 decoding
+
+ if (ord($em[0]) != 0 || ord($em[1]) > 2) {
+ user_error('Decryption error', E_USER_NOTICE);
+ return false;
+ }
+
+ $ps = substr($em, 2, strpos($em, chr(0), 2) - 2);
+ $m = substr($em, strlen($ps) + 3);
+
+ if (strlen($ps) < 8) {
+ user_error('Decryption error', E_USER_NOTICE);
+ return false;
+ }
+
+ // Output M
+
+ return $m;
+ }
+
+ /**
+ * EMSA-PSS-ENCODE
+ *
+ * See {@link http://tools.ietf.org/html/rfc3447#section-9.1.1 RFC3447#section-9.1.1}.
+ *
+ * @access private
+ * @param String $m
+ * @param Integer $emBits
+ */
+ function _emsa_pss_encode($m, $emBits)
+ {
+ // if $m is larger than two million terrabytes and you're using sha1, PKCS#1 suggests a "Label too long" error
+ // be output.
+
+ $emLen = ($emBits + 1) >> 3; // ie. ceil($emBits / 8)
+ $sLen = $this->sLen == false ? $this->hLen : $this->sLen;
+
+ $mHash = $this->hash->hash($m);
+ if ($emLen < $this->hLen + $sLen + 2) {
+ user_error('Encoding error', E_USER_NOTICE);
+ return false;
+ }
+
+ $salt = $this->_random($sLen);
+ $m2 = "\0\0\0\0\0\0\0\0" . $mHash . $salt;
+ $h = $this->hash->hash($m2);
+ $ps = str_repeat(chr(0), $emLen - $sLen - $this->hLen - 2);
+ $db = $ps . chr(1) . $salt;
+ $dbMask = $this->_mgf1($h, $emLen - $this->hLen - 1);
+ $maskedDB = $db ^ $dbMask;
+ $maskedDB[0] = ~chr(0xFF << ($emBits & 7)) & $maskedDB[0];
+ $em = $maskedDB . $h . chr(0xBC);
+
+ return $em;
+ }
+
+ /**
+ * EMSA-PSS-VERIFY
+ *
+ * See {@link http://tools.ietf.org/html/rfc3447#section-9.1.2 RFC3447#section-9.1.2}.
+ *
+ * @access private
+ * @param String $m
+ * @param String $em
+ * @param Integer $emBits
+ * @return String
+ */
+ function _emsa_pss_verify($m, $em, $emBits)
+ {
+ // if $m is larger than two million terrabytes and you're using sha1, PKCS#1 suggests a "Label too long" error
+ // be output.
+
+ $emLen = ($emBits + 1) >> 3; // ie. ceil($emBits / 8);
+ $sLen = $this->sLen == false ? $this->hLen : $this->sLen;
+
+ $mHash = $this->hash->hash($m);
+ if ($emLen < $this->hLen + $sLen + 2) {
+ return false;
+ }
+
+ if ($em[strlen($em) - 1] != chr(0xBC)) {
+ return false;
+ }
+
+ $maskedDB = substr($em, 0, $em - $this->hLen - 1);
+ $h = substr($em, $em - $this->hLen - 1, $this->hLen);
+ $temp = chr(0xFF << ($emBits & 7));
+ if ((~$maskedDB[0] & $temp) != $temp) {
+ return false;
+ }
+ $dbMask = $this->_mgf1($h, $emLen - $this->hLen - 1);
+ $db = $maskedDB ^ $dbMask;
+ $db[0] = ~chr(0xFF << ($emBits & 7)) & $db[0];
+ $temp = $emLen - $this->hLen - $sLen - 2;
+ if (substr($db, 0, $temp) != str_repeat(chr(0), $temp) || ord($db[$temp]) != 1) {
+ return false;
+ }
+ $salt = substr($db, $temp + 1); // should be $sLen long
+ $m2 = "\0\0\0\0\0\0\0\0" . $mHash . $salt;
+ $h2 = $this->hash->hash($m2);
+ return $h == $h2;
+ }
+
+ /**
+ * RSASSA-PSS-SIGN
+ *
+ * See {@link http://tools.ietf.org/html/rfc3447#section-8.1.1 RFC3447#section-8.1.1}.
+ *
+ * @access private
+ * @param String $m
+ * @return String
+ */
+ function _rsassa_pss_sign($m)
+ {
+ // EMSA-PSS encoding
+
+ $em = $this->_emsa_pss_encode($m, 8 * $this->k - 1);
+
+ // RSA signature
+
+ $m = $this->_os2ip($em);
+ $s = $this->_rsasp1($m);
+ $s = $this->_i2osp($s, $this->k);
+
+ // Output the signature S
+
+ return $s;
+ }
+
+ /**
+ * RSASSA-PSS-VERIFY
+ *
+ * See {@link http://tools.ietf.org/html/rfc3447#section-8.1.2 RFC3447#section-8.1.2}.
+ *
+ * @access private
+ * @param String $m
+ * @param String $s
+ * @return String
+ */
+ function _rsassa_pss_verify($m, $s)
+ {
+ // Length checking
+
+ if (strlen($s) != $this->k) {
+ user_error('Invalid signature', E_USER_NOTICE);
+ return false;
+ }
+
+ // RSA verification
+
+ $modBits = 8 * $this->k;
+
+ $s2 = $this->_os2ip($s);
+ $m2 = $this->_rsavp1($s2);
+ if ($m2 === false) {
+ user_error('Invalid signature', E_USER_NOTICE);
+ return false;
+ }
+ $em = $this->_i2osp($m2, $modBits >> 3);
+ if ($em === false) {
+ user_error('Invalid signature', E_USER_NOTICE);
+ return false;
+ }
+
+ // EMSA-PSS verification
+
+ return $this->_emsa_pss_verify($m, $em, $modBits - 1);
+ }
+
+ /**
+ * EMSA-PKCS1-V1_5-ENCODE
+ *
+ * See {@link http://tools.ietf.org/html/rfc3447#section-9.2 RFC3447#section-9.2}.
+ *
+ * @access private
+ * @param String $m
+ * @param Integer $emLen
+ * @return String
+ */
+ function _emsa_pkcs1_v1_5_encode($m, $emLen)
+ {
+ $h = $this->hash->hash($m);
+ if ($h === false) {
+ return false;
+ }
+
+ // see http://tools.ietf.org/html/rfc3447#page-43
+ switch ($this->hashName) {
+ case 'md2':
+ $t = pack('H*', '3020300c06082a864886f70d020205000410');
+ break;
+ case 'md5':
+ $t = pack('H*', '3020300c06082a864886f70d020505000410');
+ break;
+ case 'sha1':
+ $t = pack('H*', '3021300906052b0e03021a05000414');
+ break;
+ case 'sha256':
+ $t = pack('H*', '3031300d060960864801650304020105000420');
+ break;
+ case 'sha384':
+ $t = pack('H*', '3041300d060960864801650304020205000430');
+ break;
+ case 'sha512':
+ $t = pack('H*', '3051300d060960864801650304020305000440');
+ }
+ $t.= $h;
+ $tLen = strlen($t);
+
+ if ($emLen < $tLen + 11) {
+ user_error('Intended encoded message length too short', E_USER_NOTICE);
+ return false;
+ }
+
+ $ps = str_repeat(chr(0xFF), $emLen - $tLen - 3);
+
+ $em = "\0\1$ps\0$t";
+
+ return $em;
+ }
+
+ /**
+ * RSASSA-PKCS1-V1_5-SIGN
+ *
+ * See {@link http://tools.ietf.org/html/rfc3447#section-8.2.1 RFC3447#section-8.2.1}.
+ *
+ * @access private
+ * @param String $m
+ * @return String
+ */
+ function _rsassa_pkcs1_v1_5_sign($m)
+ {
+ // EMSA-PKCS1-v1_5 encoding
+
+ $em = $this->_emsa_pkcs1_v1_5_encode($m, $this->k);
+ if ($em === false) {
+ user_error('RSA modulus too short', E_USER_NOTICE);
+ return false;
+ }
+
+ // RSA signature
+
+ $m = $this->_os2ip($em);
+ $s = $this->_rsasp1($m);
+ $s = $this->_i2osp($s, $this->k);
+
+ // Output the signature S
+
+ return $s;
+ }
+
+ /**
+ * RSASSA-PKCS1-V1_5-VERIFY
+ *
+ * See {@link http://tools.ietf.org/html/rfc3447#section-8.2.2 RFC3447#section-8.2.2}.
+ *
+ * @access private
+ * @param String $m
+ * @return String
+ */
+ function _rsassa_pkcs1_v1_5_verify($m, $s)
+ {
+ // Length checking
+
+ if (strlen($s) != $this->k) {
+ user_error('Invalid signature', E_USER_NOTICE);
+ return false;
+ }
+
+ // RSA verification
+
+ $s = $this->_os2ip($s);
+ $m2 = $this->_rsavp1($s);
+ if ($m2 === false) {
+ user_error('Invalid signature', E_USER_NOTICE);
+ return false;
+ }
+ $em = $this->_i2osp($m2, $this->k);
+ if ($em === false) {
+ user_error('Invalid signature', E_USER_NOTICE);
+ return false;
+ }
+
+ // EMSA-PKCS1-v1_5 encoding
+
+ $em2 = $this->_emsa_pkcs1_v1_5_encode($m, $this->k);
+ if ($em2 === false) {
+ user_error('RSA modulus too short', E_USER_NOTICE);
+ return false;
+ }
+
+ // Compare
+
+ return $em === $em2;
+ }
+
+ /**
+ * Set Encryption Mode
+ *
+ * Valid values include CRYPT_RSA_ENCRYPTION_OAEP and CRYPT_RSA_ENCRYPTION_PKCS1.
+ *
+ * @access public
+ * @param Integer $mode
+ */
+ function setEncryptionMode($mode)
+ {
+ $this->encryptionMode = $mode;
+ }
+
+ /**
+ * Set Signature Mode
+ *
+ * Valid values include CRYPT_RSA_SIGNATURE_PSS and CRYPT_RSA_SIGNATURE_PKCS1
+ *
+ * @access public
+ * @param Integer $mode
+ */
+ function setSignatureMode($mode)
+ {
+ $this->signatureMode = $mode;
+ }
+
+ /**
+ * Encryption
+ *
+ * Both CRYPT_RSA_ENCRYPTION_OAEP and CRYPT_RSA_ENCRYPTION_PKCS1 both place limits on how long $plaintext can be.
+ * If $plaintext exceeds those limits it will be broken up so that it does and the resultant ciphertext's will
+ * be concatenated together.
+ *
+ * @see decrypt()
+ * @access public
+ * @param String $plaintext
+ * @return String
+ */
+ function encrypt($plaintext)
+ {
+ switch ($this->encryptionMode) {
+ case CRYPT_RSA_ENCRYPTION_PKCS1:
+ $length = $this->k - 11;
+ if ($length <= 0) {
+ return false;
+ }
+
+ $plaintext = str_split($plaintext, $length);
+ $ciphertext = '';
+ foreach ($plaintext as $m) {
+ $ciphertext.= $this->_rsaes_pkcs1_v1_5_encrypt($m);
+ }
+ return $ciphertext;
+ //case CRYPT_RSA_ENCRYPTION_OAEP:
+ default:
+ $length = $this->k - 2 * $this->hLen - 2;
+ if ($length <= 0) {
+ return false;
+ }
+
+ $plaintext = str_split($plaintext, $length);
+ $ciphertext = '';
+ foreach ($plaintext as $m) {
+ $ciphertext.= $this->_rsaes_oaep_encrypt($m);
+ }
+ return $ciphertext;
+ }
+ }
+
+ /**
+ * Decryption
+ *
+ * @see encrypt()
+ * @access public
+ * @param String $plaintext
+ * @return String
+ */
+ function decrypt($ciphertext)
+ {
+ if ($this->k <= 0) {
+ return false;
+ }
+
+ $ciphertext = str_split($ciphertext, $this->k);
+ $plaintext = '';
+
+ switch ($this->encryptionMode) {
+ case CRYPT_RSA_ENCRYPTION_PKCS1:
+ $decrypt = '_rsaes_pkcs1_v1_5_decrypt';
+ break;
+ //case CRYPT_RSA_ENCRYPTION_OAEP:
+ default:
+ $decrypt = '_rsaes_oaep_decrypt';
+ }
+
+ foreach ($ciphertext as $c) {
+ $temp = $this->$decrypt($c);
+ if ($temp === false) {
+ return false;
+ }
+ $plaintext.= $temp;
+ }
+
+ return $plaintext;
+ }
+
+ /**
+ * Create a signature
+ *
+ * @see verify()
+ * @access public
+ * @param String $message
+ * @return String
+ */
+ function sign($message)
+ {
+ if (empty($this->modulus) || empty($this->exponent)) {
+ return false;
+ }
+
+ switch ($this->signatureMode) {
+ case CRYPT_RSA_SIGNATURE_PKCS1:
+ return $this->_rsassa_pkcs1_v1_5_sign($message);
+ //case CRYPT_RSA_SIGNATURE_PSS:
+ default:
+ return $this->_rsassa_pss_sign($message);
+ }
+ }
+
+ /**
+ * Verifies a signature
+ *
+ * @see sign()
+ * @access public
+ * @param String $message
+ * @param String $signature
+ * @return Boolean
+ */
+ function verify($message, $signature)
+ {
+ if (empty($this->modulus) || empty($this->exponent)) {
+ return false;
+ }
+
+ switch ($this->signatureMode) {
+ case CRYPT_RSA_SIGNATURE_PKCS1:
+ return $this->_rsassa_pkcs1_v1_5_verify($message, $signature);
+ //case CRYPT_RSA_SIGNATURE_PSS:
+ default:
+ return $this->_rsassa_pss_verify($message, $signature);
+ }
+ }
+}
\ No newline at end of file |