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OpenId.php
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OpenId.php
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<?php
/**
* Zend Framework
*
* LICENSE
*
* This source file is subject to the new BSD license that is bundled
* with this package in the file LICENSE.txt.
* It is also available through the world-wide-web at this URL:
* http://framework.zend.com/license/new-bsd
* If you did not receive a copy of the license and are unable to
* obtain it through the world-wide-web, please send an email
* to license@zend.com so we can send you a copy immediately.
*
* @category Zend
* @package Zend_OpenId
* @copyright Copyright (c) 2005-2012 Zend Technologies USA Inc. (http://www.zend.com)
* @license http://framework.zend.com/license/new-bsd New BSD License
* @version $Id$
*/
/**
* @see Zend_Controller_Response_Abstract
*/
require_once "Zend/Controller/Response/Abstract.php";
/**
* Static class that contains common utility functions for
* {@link Zend_OpenId_Consumer} and {@link Zend_OpenId_Provider}.
*
* This class implements common utility functions that are used by both
* Consumer and Provider. They include functions for Diffie-Hellman keys
* generation and exchange, URL normalization, HTTP redirection and some others.
*
* @category Zend
* @package Zend_OpenId
* @copyright Copyright (c) 2005-2012 Zend Technologies USA Inc. (http://www.zend.com)
* @license http://framework.zend.com/license/new-bsd New BSD License
*/
class Zend_OpenId
{
/**
* Default Diffie-Hellman key generator (1024 bit)
*/
const DH_P = 'dcf93a0b883972ec0e19989ac5a2ce310e1d37717e8d9571bb7623731866e61ef75a2e27898b057f9891c2e27a639c3f29b60814581cd3b2ca3986d2683705577d45c2e7e52dc81c7a171876e5cea74b1448bfdfaf18828efd2519f14e45e3826634af1949e5b535cc829a483b8a76223e5d490a257f05bdff16f2fb22c583ab';
/**
* Default Diffie-Hellman prime number (should be 2 or 5)
*/
const DH_G = '02';
/**
* OpenID 2.0 namespace. All OpenID 2.0 messages MUST contain variable
* openid.ns with its value.
*/
const NS_2_0 = 'http://specs.openid.net/auth/2.0';
/**
* Allows enable/disable stoping execution of PHP script after redirect()
*/
static public $exitOnRedirect = true;
/**
* Alternative request URL that can be used to override the default
* selfUrl() response
*/
static public $selfUrl = null;
/**
* Sets alternative request URL that can be used to override the default
* selfUrl() response
*
* @param string $selfUrl the URL to be set
* @return string the old value of overriding URL
*/
static public function setSelfUrl($selfUrl = null)
{
$ret = self::$selfUrl;
self::$selfUrl = $selfUrl;
return $ret;
}
/**
* Returns a full URL that was requested on current HTTP request.
*
* @return string
*/
static public function selfUrl()
{
if (self::$selfUrl !== null) {
return self::$selfUrl;
} if (isset($_SERVER['SCRIPT_URI'])) {
return $_SERVER['SCRIPT_URI'];
}
$url = '';
$port = '';
if (isset($_SERVER['HTTP_HOST'])) {
if (($pos = strpos($_SERVER['HTTP_HOST'], ':')) === false) {
if (isset($_SERVER['SERVER_PORT'])) {
$port = ':' . $_SERVER['SERVER_PORT'];
}
$url = $_SERVER['HTTP_HOST'];
} else {
$url = substr($_SERVER['HTTP_HOST'], 0, $pos);
$port = substr($_SERVER['HTTP_HOST'], $pos);
}
} else if (isset($_SERVER['SERVER_NAME'])) {
$url = $_SERVER['SERVER_NAME'];
if (isset($_SERVER['SERVER_PORT'])) {
$port = ':' . $_SERVER['SERVER_PORT'];
}
}
if (isset($_SERVER['HTTPS']) && $_SERVER['HTTPS'] == 'on') {
$url = 'https://' . $url;
if ($port == ':443') {
$port = '';
}
} else {
$url = 'http://' . $url;
if ($port == ':80') {
$port = '';
}
}
$url .= $port;
if (isset($_SERVER['HTTP_X_REWRITE_URL'])) {
$url .= $_SERVER['HTTP_X_REWRITE_URL'];
} elseif (isset($_SERVER['REQUEST_URI'])) {
$query = strpos($_SERVER['REQUEST_URI'], '?');
if ($query === false) {
$url .= $_SERVER['REQUEST_URI'];
} else {
$url .= substr($_SERVER['REQUEST_URI'], 0, $query);
}
} else if (isset($_SERVER['SCRIPT_URL'])) {
$url .= $_SERVER['SCRIPT_URL'];
} else if (isset($_SERVER['REDIRECT_URL'])) {
$url .= $_SERVER['REDIRECT_URL'];
} else if (isset($_SERVER['PHP_SELF'])) {
$url .= $_SERVER['PHP_SELF'];
} else if (isset($_SERVER['SCRIPT_NAME'])) {
$url .= $_SERVER['SCRIPT_NAME'];
if (isset($_SERVER['PATH_INFO'])) {
$url .= $_SERVER['PATH_INFO'];
}
}
return $url;
}
/**
* Returns an absolute URL for the given one
*
* @param string $url absilute or relative URL
* @return string
*/
static public function absoluteUrl($url)
{
if (empty($url)) {
return Zend_OpenId::selfUrl();
} else if (!preg_match('|^([^:]+)://|', $url)) {
if (preg_match('|^([^:]+)://([^:@]*(?:[:][^@]*)?@)?([^/:@?#]*)(?:[:]([^/?#]*))?(/[^?]*)?((?:[?](?:[^#]*))?(?:#.*)?)$|', Zend_OpenId::selfUrl(), $reg)) {
$scheme = $reg[1];
$auth = $reg[2];
$host = $reg[3];
$port = $reg[4];
$path = $reg[5];
$query = $reg[6];
if ($url[0] == '/') {
return $scheme
. '://'
. $auth
. $host
. (empty($port) ? '' : (':' . $port))
. $url;
} else {
$dir = dirname($path);
return $scheme
. '://'
. $auth
. $host
. (empty($port) ? '' : (':' . $port))
. (strlen($dir) > 1 ? $dir : '')
. '/'
. $url;
}
}
}
return $url;
}
/**
* Converts variable/value pairs into URL encoded query string
*
* @param array $params variable/value pairs
* @return string URL encoded query string
*/
static public function paramsToQuery($params)
{
foreach($params as $key => $value) {
if (isset($query)) {
$query .= '&' . $key . '=' . urlencode($value);
} else {
$query = $key . '=' . urlencode($value);
}
}
return isset($query) ? $query : '';
}
/**
* Normalizes URL according to RFC 3986 to use it in comparison operations.
* The function gets URL argument by reference and modifies it.
* It returns true on success and false of failure.
*
* @param string &$id url to be normalized
* @return bool
*/
static public function normalizeUrl(&$id)
{
// RFC 3986, 6.2.2. Syntax-Based Normalization
// RFC 3986, 6.2.2.2 Percent-Encoding Normalization
$i = 0;
$n = strlen($id);
$res = '';
while ($i < $n) {
if ($id[$i] == '%') {
if ($i + 2 >= $n) {
return false;
}
++$i;
if ($id[$i] >= '0' && $id[$i] <= '9') {
$c = ord($id[$i]) - ord('0');
} else if ($id[$i] >= 'A' && $id[$i] <= 'F') {
$c = ord($id[$i]) - ord('A') + 10;
} else if ($id[$i] >= 'a' && $id[$i] <= 'f') {
$c = ord($id[$i]) - ord('a') + 10;
} else {
return false;
}
++$i;
if ($id[$i] >= '0' && $id[$i] <= '9') {
$c = ($c << 4) | (ord($id[$i]) - ord('0'));
} else if ($id[$i] >= 'A' && $id[$i] <= 'F') {
$c = ($c << 4) | (ord($id[$i]) - ord('A') + 10);
} else if ($id[$i] >= 'a' && $id[$i] <= 'f') {
$c = ($c << 4) | (ord($id[$i]) - ord('a') + 10);
} else {
return false;
}
++$i;
$ch = chr($c);
if (($ch >= 'A' && $ch <= 'Z') ||
($ch >= 'a' && $ch <= 'z') ||
$ch == '-' ||
$ch == '.' ||
$ch == '_' ||
$ch == '~') {
$res .= $ch;
} else {
$res .= '%';
if (($c >> 4) < 10) {
$res .= chr(($c >> 4) + ord('0'));
} else {
$res .= chr(($c >> 4) - 10 + ord('A'));
}
$c = $c & 0xf;
if ($c < 10) {
$res .= chr($c + ord('0'));
} else {
$res .= chr($c - 10 + ord('A'));
}
}
} else {
$res .= $id[$i++];
}
}
if (!preg_match('|^([^:]+)://([^:@]*(?:[:][^@]*)?@)?([^/:@?#]*)(?:[:]([^/?#]*))?(/[^?#]*)?((?:[?](?:[^#]*))?)((?:#.*)?)$|', $res, $reg)) {
return false;
}
$scheme = $reg[1];
$auth = $reg[2];
$host = $reg[3];
$port = $reg[4];
$path = $reg[5];
$query = $reg[6];
$fragment = $reg[7]; /* strip it */ /* ZF-4358 Fragment retained under OpenID 2.0 */
if (empty($scheme) || empty($host)) {
return false;
}
// RFC 3986, 6.2.2.1. Case Normalization
$scheme = strtolower($scheme);
$host = strtolower($host);
// RFC 3986, 6.2.2.3. Path Segment Normalization
if (!empty($path)) {
$i = 0;
$n = strlen($path);
$res = "";
while ($i < $n) {
if ($path[$i] == '/') {
++$i;
while ($i < $n && $path[$i] == '/') {
++$i;
}
if ($i < $n && $path[$i] == '.') {
++$i;
if ($i < $n && $path[$i] == '.') {
++$i;
if ($i == $n || $path[$i] == '/') {
if (($pos = strrpos($res, '/')) !== false) {
$res = substr($res, 0, $pos);
}
} else {
$res .= '/..';
}
} else if ($i != $n && $path[$i] != '/') {
$res .= '/.';
}
} else {
$res .= '/';
}
} else {
$res .= $path[$i++];
}
}
$path = $res;
}
// RFC 3986,6.2.3. Scheme-Based Normalization
if ($scheme == 'http') {
if ($port == 80) {
$port = '';
}
} else if ($scheme == 'https') {
if ($port == 443) {
$port = '';
}
}
if (empty($path)) {
$path = '/';
}
$id = $scheme
. '://'
. $auth
. $host
. (empty($port) ? '' : (':' . $port))
. $path
. $query
. $fragment;
return true;
}
/**
* Normalizes OpenID identifier that can be URL or XRI name.
* Returns true on success and false of failure.
*
* Normalization is performed according to the following rules:
* 1. If the user's input starts with one of the "xri://", "xri://$ip*",
* or "xri://$dns*" prefixes, they MUST be stripped off, so that XRIs
* are used in the canonical form, and URI-authority XRIs are further
* considered URL identifiers.
* 2. If the first character of the resulting string is an XRI Global
* Context Symbol ("=", "@", "+", "$", "!"), then the input SHOULD be
* treated as an XRI.
* 3. Otherwise, the input SHOULD be treated as an http URL; if it does
* not include a "http" or "https" scheme, the Identifier MUST be
* prefixed with the string "http://".
* 4. URL identifiers MUST then be further normalized by both following
* redirects when retrieving their content and finally applying the
* rules in Section 6 of [RFC3986] to the final destination URL.
* @param string &$id identifier to be normalized
* @return bool
*/
static public function normalize(&$id)
{
$id = trim($id);
if (strlen($id) === 0) {
return true;
}
// 7.2.1
if (strpos($id, 'xri://$ip*') === 0) {
$id = substr($id, strlen('xri://$ip*'));
} else if (strpos($id, 'xri://$dns*') === 0) {
$id = substr($id, strlen('xri://$dns*'));
} else if (strpos($id, 'xri://') === 0) {
$id = substr($id, strlen('xri://'));
}
// 7.2.2
if ($id[0] == '=' ||
$id[0] == '@' ||
$id[0] == '+' ||
$id[0] == '$' ||
$id[0] == '!') {
return true;
}
// 7.2.3
if (strpos($id, "://") === false) {
$id = 'http://' . $id;
}
// 7.2.4
return self::normalizeURL($id);
}
/**
* Performs a HTTP redirection to specified URL with additional data.
* It may generate redirected request using GET or POST HTTP method.
* The function never returns.
*
* @param string $url URL to redirect to
* @param array $params additional variable/value pairs to send
* @param Zend_Controller_Response_Abstract $response
* @param string $method redirection method ('GET' or 'POST')
*/
static public function redirect($url, $params = null,
Zend_Controller_Response_Abstract $response = null, $method = 'GET')
{
$url = Zend_OpenId::absoluteUrl($url);
$body = "";
if (null === $response) {
require_once "Zend/Controller/Response/Http.php";
$response = new Zend_Controller_Response_Http();
}
if ($method == 'POST') {
$body = "<html><body onLoad=\"document.forms[0].submit();\">\n";
$body .= "<form method=\"POST\" action=\"$url\">\n";
if (is_array($params) && count($params) > 0) {
foreach($params as $key => $value) {
$body .= '<input type="hidden" name="' . $key . '" value="' . $value . "\">\n";
}
}
$body .= "<input type=\"submit\" value=\"Continue OpenID transaction\">\n";
$body .= "</form></body></html>\n";
} else if (is_array($params) && count($params) > 0) {
if (strpos($url, '?') === false) {
$url .= '?' . self::paramsToQuery($params);
} else {
$url .= '&' . self::paramsToQuery($params);
}
}
if (!empty($body)) {
$response->setBody($body);
} else if (!$response->canSendHeaders()) {
$response->setBody("<script language=\"JavaScript\"" .
" type=\"text/javascript\">window.location='$url';" .
"</script>");
} else {
$response->setRedirect($url);
}
$response->sendResponse();
if (self::$exitOnRedirect) {
exit();
}
}
/**
* Produces string of random byte of given length.
*
* @param integer $len length of requested string
* @return string RAW random binary string
*/
static public function randomBytes($len)
{
$key = '';
for($i=0; $i < $len; $i++) {
$key .= chr(mt_rand(0, 255));
}
return $key;
}
/**
* Generates a hash value (message digest) according to given algorithm.
* It returns RAW binary string.
*
* This is a wrapper function that uses one of available internal function
* dependent on given PHP configuration. It may use various functions from
* ext/openssl, ext/hash, ext/mhash or ext/standard.
*
* @param string $func digest algorithm
* @param string $data data to sign
* @return string RAW digital signature
* @throws Zend_OpenId_Exception
*/
static public function digest($func, $data)
{
if (function_exists('openssl_digest')) {
return openssl_digest($data, $func, true);
} else if (function_exists('hash')) {
return hash($func, $data, true);
} else if ($func === 'sha1') {
return sha1($data, true);
} else if ($func === 'sha256') {
if (function_exists('mhash')) {
return mhash(MHASH_SHA256 , $data);
}
}
require_once "Zend/OpenId/Exception.php";
throw new Zend_OpenId_Exception(
'Unsupported digest algorithm "' . $func . '".',
Zend_OpenId_Exception::UNSUPPORTED_DIGEST);
}
/**
* Generates a keyed hash value using the HMAC method. It uses ext/hash
* if available or user-level PHP implementation, that is not significantly
* slower.
*
* @param string $macFunc name of selected hashing algorithm (sha1, sha256)
* @param string $data data to sign
* @param string $secret shared secret key used for generating the HMAC
* variant of the message digest
* @return string RAW HMAC value
*/
static public function hashHmac($macFunc, $data, $secret)
{
// require_once "Zend/Crypt/Hmac.php";
// return Zend_Crypt_Hmac::compute($secret, $macFunc, $data, Zend_Crypt_Hmac::BINARY);
if (function_exists('hash_hmac')) {
return hash_hmac($macFunc, $data, $secret, 1);
} else {
if (Zend_OpenId::strlen($secret) > 64) {
$secret = self::digest($macFunc, $secret);
}
$secret = str_pad($secret, 64, chr(0x00));
$ipad = str_repeat(chr(0x36), 64);
$opad = str_repeat(chr(0x5c), 64);
$hash1 = self::digest($macFunc, ($secret ^ $ipad) . $data);
return self::digest($macFunc, ($secret ^ $opad) . $hash1);
}
}
/**
* Converts binary representation into ext/gmp or ext/bcmath big integer
* representation.
*
* @param string $bin binary representation of big number
* @return mixed
* @throws Zend_OpenId_Exception
*/
static protected function binToBigNum($bin)
{
if (extension_loaded('gmp')) {
return gmp_init(bin2hex($bin), 16);
} else if (extension_loaded('bcmath')) {
$bn = 0;
$len = Zend_OpenId::strlen($bin);
for ($i = 0; $i < $len; $i++) {
$bn = bcmul($bn, 256);
$bn = bcadd($bn, ord($bin[$i]));
}
return $bn;
}
require_once "Zend/OpenId/Exception.php";
throw new Zend_OpenId_Exception(
'The system doesn\'t have proper big integer extension',
Zend_OpenId_Exception::UNSUPPORTED_LONG_MATH);
}
/**
* Converts internal ext/gmp or ext/bcmath big integer representation into
* binary string.
*
* @param mixed $bn big number
* @return string
* @throws Zend_OpenId_Exception
*/
static protected function bigNumToBin($bn)
{
if (extension_loaded('gmp')) {
$s = gmp_strval($bn, 16);
if (strlen($s) % 2 != 0) {
$s = '0' . $s;
} else if ($s[0] > '7') {
$s = '00' . $s;
}
return pack("H*", $s);
} else if (extension_loaded('bcmath')) {
$cmp = bccomp($bn, 0);
if ($cmp == 0) {
return "\0";
} else if ($cmp < 0) {
require_once "Zend/OpenId/Exception.php";
throw new Zend_OpenId_Exception(
'Big integer arithmetic error',
Zend_OpenId_Exception::ERROR_LONG_MATH);
}
$bin = "";
while (bccomp($bn, 0) > 0) {
$bin = chr(bcmod($bn, 256)) . $bin;
$bn = bcdiv($bn, 256);
}
if (ord($bin[0]) > 127) {
$bin = "\0" . $bin;
}
return $bin;
}
require_once "Zend/OpenId/Exception.php";
throw new Zend_OpenId_Exception(
'The system doesn\'t have proper big integer extension',
Zend_OpenId_Exception::UNSUPPORTED_LONG_MATH);
}
/**
* Performs the first step of a Diffie-Hellman key exchange by generating
* private and public DH values based on given prime number $p and
* generator $g. Both sides of key exchange MUST have the same prime number
* and generator. In this case they will able to create a random shared
* secret that is never send from one to the other.
*
* @param string $p prime number in binary representation
* @param string $g generator in binary representation
* @param string $priv_key private key in binary representation
* @return mixed
*/
static public function createDhKey($p, $g, $priv_key = null)
{
if (function_exists('openssl_dh_compute_key')) {
$dh_details = array(
'p' => $p,
'g' => $g
);
if ($priv_key !== null) {
$dh_details['priv_key'] = $priv_key;
}
return openssl_pkey_new(array('dh'=>$dh_details));
} else {
$bn_p = self::binToBigNum($p);
$bn_g = self::binToBigNum($g);
if ($priv_key === null) {
$priv_key = self::randomBytes(Zend_OpenId::strlen($p));
}
$bn_priv_key = self::binToBigNum($priv_key);
if (extension_loaded('gmp')) {
$bn_pub_key = gmp_powm($bn_g, $bn_priv_key, $bn_p);
} else if (extension_loaded('bcmath')) {
$bn_pub_key = bcpowmod($bn_g, $bn_priv_key, $bn_p);
}
$pub_key = self::bigNumToBin($bn_pub_key);
return array(
'p' => $bn_p,
'g' => $bn_g,
'priv_key' => $bn_priv_key,
'pub_key' => $bn_pub_key,
'details' => array(
'p' => $p,
'g' => $g,
'priv_key' => $priv_key,
'pub_key' => $pub_key));
}
}
/**
* Returns an associative array with Diffie-Hellman key components in
* binary representation. The array includes original prime number 'p' and
* generator 'g', random private key 'priv_key' and corresponding public
* key 'pub_key'.
*
* @param mixed $dh Diffie-Hellman key
* @return array
*/
static public function getDhKeyDetails($dh)
{
if (function_exists('openssl_dh_compute_key')) {
$details = openssl_pkey_get_details($dh);
if (isset($details['dh'])) {
return $details['dh'];
}
} else {
return $dh['details'];
}
}
/**
* Computes the shared secret from the private DH value $dh and the other
* party's public value in $pub_key
*
* @param string $pub_key other party's public value
* @param mixed $dh Diffie-Hellman key
* @return string
* @throws Zend_OpenId_Exception
*/
static public function computeDhSecret($pub_key, $dh)
{
if (function_exists('openssl_dh_compute_key')) {
$ret = openssl_dh_compute_key($pub_key, $dh);
if (ord($ret[0]) > 127) {
$ret = "\0" . $ret;
}
return $ret;
} else if (extension_loaded('gmp')) {
$bn_pub_key = self::binToBigNum($pub_key);
$bn_secret = gmp_powm($bn_pub_key, $dh['priv_key'], $dh['p']);
return self::bigNumToBin($bn_secret);
} else if (extension_loaded('bcmath')) {
$bn_pub_key = self::binToBigNum($pub_key);
$bn_secret = bcpowmod($bn_pub_key, $dh['priv_key'], $dh['p']);
return self::bigNumToBin($bn_secret);
}
require_once "Zend/OpenId/Exception.php";
throw new Zend_OpenId_Exception(
'The system doesn\'t have proper big integer extension',
Zend_OpenId_Exception::UNSUPPORTED_LONG_MATH);
}
/**
* Takes an arbitrary precision integer and returns its shortest big-endian
* two's complement representation.
*
* Arbitrary precision integers MUST be encoded as big-endian signed two's
* complement binary strings. Henceforth, "btwoc" is a function that takes
* an arbitrary precision integer and returns its shortest big-endian two's
* complement representation. All integers that are used with
* Diffie-Hellman Key Exchange are positive. This means that the left-most
* bit of the two's complement representation MUST be zero. If it is not,
* implementations MUST add a zero byte at the front of the string.
*
* @param string $str binary representation of arbitrary precision integer
* @return string big-endian signed representation
*/
static public function btwoc($str)
{
if (ord($str[0]) > 127) {
return "\0" . $str;
}
return $str;
}
/**
* Returns lenght of binary string in bytes
*
* @param string $str
* @return int the string lenght
*/
static public function strlen($str)
{
if (extension_loaded('mbstring') &&
(((int)ini_get('mbstring.func_overload')) & 2)) {
return mb_strlen($str, 'latin1');
} else {
return strlen($str);
}
}
}