Viewing file:  TrustRoot.php (14.03 KB) -rwxrwxr-x
Select action/file-type:
 (+) |  (+) |  (+) | Code (+) | Session (+) |  (+) | SDB (+) |  (+) |  (+) |  (+) |  (+) |  (+) |
<?php
/**
* Functions for dealing with OpenID trust roots
*
* PHP versions 4 and 5
*
* LICENSE: See the COPYING file included in this distribution.
*
* @package OpenID
* @author JanRain, Inc. <openid@janrain.com>
* @copyright 2005-2008 Janrain, Inc.
* @license http://www.apache.org/licenses/LICENSE-2.0 Apache
*/
require_once 'Auth/OpenID/Discover.php';
/**
* A regular expression that matches a domain ending in a top-level domains.
* Used in checking trust roots for sanity.
*
* @access private
*/
define('Auth_OpenID___TLDs',
'/\.(ac|ad|ae|aero|af|ag|ai|al|am|an|ao|aq|ar|arpa|as|asia' .
'|at|au|aw|ax|az|ba|bb|bd|be|bf|bg|bh|bi|biz|bj|bm|bn|bo|br' .
'|bs|bt|bv|bw|by|bz|ca|cat|cc|cd|cf|cg|ch|ci|ck|cl|cm|cn|co' .
'|com|coop|cr|cu|cv|cx|cy|cz|de|dj|dk|dm|do|dz|ec|edu|ee|eg' .
'|er|es|et|eu|fi|fj|fk|fm|fo|fr|ga|gb|gd|ge|gf|gg|gh|gi|gl' .
'|gm|gn|gov|gp|gq|gr|gs|gt|gu|gw|gy|hk|hm|hn|hr|ht|hu|id|ie' .
'|il|im|in|info|int|io|iq|ir|is|it|je|jm|jo|jobs|jp|ke|kg|kh' .
'|ki|km|kn|kp|kr|kw|ky|kz|la|lb|lc|li|lk|lr|ls|lt|lu|lv|ly' .
'|ma|mc|md|me|mg|mh|mil|mk|ml|mm|mn|mo|mobi|mp|mq|mr|ms|mt' .
'|mu|museum|mv|mw|mx|my|mz|na|name|nc|ne|net|nf|ng|ni|nl|no' .
'|np|nr|nu|nz|om|org|pa|pe|pf|pg|ph|pk|pl|pm|pn|pr|pro|ps|pt' .
'|pw|py|qa|re|ro|rs|ru|rw|sa|sb|sc|sd|se|sg|sh|si|sj|sk|sl' .
'|sm|sn|so|sr|st|su|sv|sy|sz|tc|td|tel|tf|tg|th|tj|tk|tl|tm' .
'|tn|to|tp|tr|travel|tt|tv|tw|tz|ua|ug|uk|us|uy|uz|va|vc|ve' .
'|vg|vi|vn|vu|wf|ws|xn--0zwm56d|xn--11b5bs3a9aj6g' .
'|xn--80akhbyknj4f|xn--9t4b11yi5a|xn--deba0ad|xn--g6w251d' .
'|xn--hgbk6aj7f53bba|xn--hlcj6aya9esc7a|xn--jxalpdlp' .
'|xn--kgbechtv|xn--zckzah|ye|yt|yu|za|zm|zw)\.?$/');
define('Auth_OpenID___HostSegmentRe',
"/^(?:[-a-zA-Z0-9!$&'\\(\\)\\*+,;=._~]|%[a-zA-Z0-9]{2})*$/");
/**
* A wrapper for trust-root related functions
*/
class Auth_OpenID_TrustRoot {
/*
* Return a discovery URL for this realm.
*
* Return null if the realm could not be parsed or was not valid.
*
* @param return_to The relying party return URL of the OpenID
* authentication request
*
* @return The URL upon which relying party discovery should be
* run in order to verify the return_to URL
*/
static function buildDiscoveryURL($realm)
{
$parsed = Auth_OpenID_TrustRoot::_parse($realm);
if ($parsed === false) {
return false;
}
if ($parsed['wildcard']) {
// Use "www." in place of the star
if ($parsed['host'][0] != '.') {
return false;
}
$www_domain = 'www' . $parsed['host'];
return sprintf('%s://%s%s', $parsed['scheme'],
$www_domain, $parsed['path']);
} else {
return $parsed['unparsed'];
}
}
/**
* Parse a URL into its trust_root parts.
*
* @static
*
* @access private
*
* @param string $trust_root The url to parse
*
* @return mixed $parsed Either an associative array of trust root
* parts or false if parsing failed.
*/
static function _parse($trust_root)
{
$trust_root = Auth_OpenID_urinorm($trust_root);
if ($trust_root === null) {
return false;
}
if (preg_match("/:\/\/[^:]+(:\d+){2,}(\/|$)/", $trust_root)) {
return false;
}
$parts = @parse_url($trust_root);
if ($parts === false) {
return false;
}
$required_parts = array('scheme', 'host');
$forbidden_parts = array('user', 'pass', 'fragment');
$keys = array_keys($parts);
if (array_intersect($keys, $required_parts) != $required_parts) {
return false;
}
if (array_intersect($keys, $forbidden_parts) != array()) {
return false;
}
if (!preg_match(Auth_OpenID___HostSegmentRe, $parts['host'])) {
return false;
}
$scheme = strtolower($parts['scheme']);
$allowed_schemes = array('http', 'https');
if (!in_array($scheme, $allowed_schemes)) {
return false;
}
$parts['scheme'] = $scheme;
$host = strtolower($parts['host']);
$hostparts = explode('*', $host);
switch (count($hostparts)) {
case 1:
$parts['wildcard'] = false;
break;
case 2:
if ($hostparts[0] ||
($hostparts[1] && substr($hostparts[1], 0, 1) != '.')) {
return false;
}
$host = $hostparts[1];
$parts['wildcard'] = true;
break;
default:
return false;
}
if (strpos($host, ':') !== false) {
return false;
}
$parts['host'] = $host;
if (isset($parts['path'])) {
$path = strtolower($parts['path']);
if (substr($path, 0, 1) != '/') {
return false;
}
} else {
$path = '/';
}
$parts['path'] = $path;
if (!isset($parts['port'])) {
$parts['port'] = false;
}
$parts['unparsed'] = $trust_root;
return $parts;
}
/**
* Is this trust root sane?
*
* A trust root is sane if it is syntactically valid and it has a
* reasonable domain name. Specifically, the domain name must be
* more than one level below a standard TLD or more than two
* levels below a two-letter tld.
*
* For example, '*.com' is not a sane trust root, but '*.foo.com'
* is. '*.co.uk' is not sane, but '*.bbc.co.uk' is.
*
* This check is not always correct, but it attempts to err on the
* side of marking sane trust roots insane instead of marking
* insane trust roots sane. For example, 'kink.fm' is marked as
* insane even though it "should" (for some meaning of should) be
* marked sane.
*
* This function should be used when creating OpenID servers to
* alert the users of the server when a consumer attempts to get
* the user to accept a suspicious trust root.
*
* @static
* @param string $trust_root The trust root to check
* @return bool $sanity Whether the trust root looks OK
*/
static function isSane($trust_root)
{
$parts = Auth_OpenID_TrustRoot::_parse($trust_root);
if ($parts === false) {
return false;
}
// Localhost is a special case
if ($parts['host'] == 'localhost') {
return true;
}
$host_parts = explode('.', $parts['host']);
if ($parts['wildcard']) {
// Remove the empty string from the beginning of the array
array_shift($host_parts);
}
if ($host_parts && !$host_parts[count($host_parts) - 1]) {
array_pop($host_parts);
}
if (!$host_parts) {
return false;
}
// Don't allow adjacent dots
if (in_array('', $host_parts, true)) {
return false;
}
// Get the top-level domain of the host. If it is not a valid TLD,
// it's not sane.
preg_match(Auth_OpenID___TLDs, $parts['host'], $matches);
if (!$matches) {
return false;
}
$tld = $matches[1];
if (count($host_parts) == 1) {
return false;
}
if ($parts['wildcard']) {
// It's a 2-letter tld with a short second to last segment
// so there needs to be more than two segments specified
// (e.g. *.co.uk is insane)
$second_level = $host_parts[count($host_parts) - 2];
if (strlen($tld) == 2 && strlen($second_level) <= 3) {
return count($host_parts) > 2;
}
}
return true;
}
/**
* Does this URL match the given trust root?
*
* Return whether the URL falls under the given trust root. This
* does not check whether the trust root is sane. If the URL or
* trust root do not parse, this function will return false.
*
* @param string $trust_root The trust root to match against
*
* @param string $url The URL to check
*
* @return bool $matches Whether the URL matches against the
* trust root
*/
static function match($trust_root, $url)
{
$trust_root_parsed = Auth_OpenID_TrustRoot::_parse($trust_root);
$url_parsed = Auth_OpenID_TrustRoot::_parse($url);
if (!$trust_root_parsed || !$url_parsed) {
return false;
}
// Check hosts matching
if ($url_parsed['wildcard']) {
return false;
}
if ($trust_root_parsed['wildcard']) {
$host_tail = $trust_root_parsed['host'];
$host = $url_parsed['host'];
if ($host_tail &&
substr($host, -(strlen($host_tail))) != $host_tail &&
substr($host_tail, 1) != $host) {
return false;
}
} else {
if ($trust_root_parsed['host'] != $url_parsed['host']) {
return false;
}
}
// Check path and query matching
$base_path = $trust_root_parsed['path'];
$path = $url_parsed['path'];
if (!isset($trust_root_parsed['query'])) {
if ($base_path != $path) {
if (substr($path, 0, strlen($base_path)) != $base_path) {
return false;
}
if (substr($base_path, strlen($base_path) - 1, 1) != '/' &&
substr($path, strlen($base_path), 1) != '/') {
return false;
}
}
} else {
$base_query = $trust_root_parsed['query'];
$query = @$url_parsed['query'];
$qplus = substr($query, 0, strlen($base_query) + 1);
$bqplus = $base_query . '&';
if ($base_path != $path ||
($base_query != $query && $qplus != $bqplus)) {
return false;
}
}
// The port and scheme need to match exactly
return ($trust_root_parsed['scheme'] == $url_parsed['scheme'] &&
$url_parsed['port'] === $trust_root_parsed['port']);
}
}
/*
* If the endpoint is a relying party OpenID return_to endpoint,
* return the endpoint URL. Otherwise, return None.
*
* This function is intended to be used as a filter for the Yadis
* filtering interface.
*
* @see: C{L{openid.yadis.services}}
* @see: C{L{openid.yadis.filters}}
*
* @param endpoint: An XRDS BasicServiceEndpoint, as returned by
* performing Yadis dicovery.
*
* @returns: The endpoint URL or None if the endpoint is not a
* relying party endpoint.
*/
function filter_extractReturnURL($endpoint)
{
if ($endpoint->matchTypes(array(Auth_OpenID_RP_RETURN_TO_URL_TYPE))) {
return $endpoint;
} else {
return null;
}
}
function &Auth_OpenID_extractReturnURL(&$endpoint_list)
{
$result = array();
foreach ($endpoint_list as $endpoint) {
if (filter_extractReturnURL($endpoint)) {
$result[] = $endpoint;
}
}
return $result;
}
/*
* Is the return_to URL under one of the supplied allowed return_to
* URLs?
*/
function Auth_OpenID_returnToMatches($allowed_return_to_urls, $return_to)
{
foreach ($allowed_return_to_urls as $allowed_return_to) {
// A return_to pattern works the same as a realm, except that
// it's not allowed to use a wildcard. We'll model this by
// parsing it as a realm, and not trying to match it if it has
// a wildcard.
$return_realm = Auth_OpenID_TrustRoot::_parse($allowed_return_to);
if (// Parses as a trust root
($return_realm !== false) &&
// Does not have a wildcard
(!$return_realm['wildcard']) &&
// Matches the return_to that we passed in with it
(Auth_OpenID_TrustRoot::match($allowed_return_to, $return_to))) {
return true;
}
}
// No URL in the list matched
return false;
}
/*
* Given a relying party discovery URL return a list of return_to
* URLs.
*/
function Auth_OpenID_getAllowedReturnURLs($relying_party_url, $fetcher,
$discover_function=null)
{
if ($discover_function === null) {
$discover_function = array('Auth_Yadis_Yadis', 'discover');
}
$xrds_parse_cb = array('Auth_OpenID_ServiceEndpoint', 'consumerFromXRDS');
list($rp_url_after_redirects, $endpoints) =
Auth_Yadis_getServiceEndpoints($relying_party_url, $xrds_parse_cb,
$discover_function, $fetcher);
if ($rp_url_after_redirects != $relying_party_url) {
// Verification caused a redirect
return false;
}
call_user_func_array($discover_function,
array($relying_party_url, &$fetcher));
$return_to_urls = array();
$matching_endpoints = Auth_OpenID_extractReturnURL($endpoints);
foreach ($matching_endpoints as $e) {
$return_to_urls[] = $e->server_url;
}
return $return_to_urls;
}
/*
* Verify that a return_to URL is valid for the given realm.
*
* This function builds a discovery URL, performs Yadis discovery on
* it, makes sure that the URL does not redirect, parses out the
* return_to URLs, and finally checks to see if the current return_to
* URL matches the return_to.
*
* @return true if the return_to URL is valid for the realm
*/
function Auth_OpenID_verifyReturnTo($realm_str, $return_to, $fetcher,
$_vrfy='Auth_OpenID_getAllowedReturnURLs')
{
$disco_url = Auth_OpenID_TrustRoot::buildDiscoveryURL($realm_str);
if ($disco_url === false) {
return false;
}
$allowable_urls = call_user_func_array($_vrfy,
array($disco_url, $fetcher));
// The realm_str could not be parsed.
if ($allowable_urls === false) {
return false;
}
if (Auth_OpenID_returnToMatches($allowable_urls, $return_to)) {
return true;
} else {
return false;
}
}
|