diff options
Diffstat (limited to 'library')
| -rw-r--r-- | library/openid.php | 725 |
1 files changed, 725 insertions, 0 deletions
diff --git a/library/openid.php b/library/openid.php new file mode 100644 index 000000000..7c88c02d8 --- /dev/null +++ b/library/openid.php @@ -0,0 +1,725 @@ +<?php +/** + * This class provides a simple interface for OpenID (1.1 and 2.0) authentication. + * Supports Yadis discovery. + * The authentication process is stateless/dumb. + * + * Usage: + * Sign-on with OpenID is a two step process: + * Step one is authentication with the provider: + * <code> + * $openid = new LightOpenID; + * $openid->identity = 'ID supplied by user'; + * header('Location: ' . $openid->authUrl()); + * </code> + * The provider then sends various parameters via GET, one of them is openid_mode. + * Step two is verification: + * <code> + * if ($this->data['openid_mode']) { + * $openid = new LightOpenID; + * echo $openid->validate() ? 'Logged in.' : 'Failed'; + * } + * </code> + * + * Optionally, you can set $returnUrl and $realm (or $trustRoot, which is an alias). + * The default values for those are: + * $openid->realm = (!empty($_SERVER['HTTPS']) ? 'https' : 'http') . '://' . $_SERVER['HTTP_HOST']; + * $openid->returnUrl = $openid->realm . $_SERVER['REQUEST_URI']; # without the query part, if present + * If you don't know their meaning, refer to any openid tutorial, or specification. Or just guess. + * + * AX and SREG extensions are supported. + * To use them, specify $openid->required and/or $openid->optional before calling $openid->authUrl(). + * These are arrays, with values being AX schema paths (the 'path' part of the URL). + * For example: + * $openid->required = array('namePerson/friendly', 'contact/email'); + * $openid->optional = array('namePerson/first'); + * If the server supports only SREG or OpenID 1.1, these are automaticaly + * mapped to SREG names, so that user doesn't have to know anything about the server. + * + * To get the values, use $openid->getAttributes(). + * + * + * The library requires PHP >= 5.1.2 with curl or http/https stream wrappers enabled.. + * @author Mewp + * @copyright Copyright (c) 2010, Mewp + * @license http://www.opensource.org/licenses/mit-license.php MIT + */ +class LightOpenID +{ + public $returnUrl + , $required = array() + , $optional = array() + , $verify_perr = null + , $capath = null; + private $identity, $claimed_id; + protected $server, $version, $trustRoot, $aliases, $identifier_select = false + , $ax = false, $sreg = false, $data; + static protected $ax_to_sreg = array( + 'namePerson/friendly' => 'nickname', + 'contact/email' => 'email', + 'namePerson' => 'fullname', + 'birthDate' => 'dob', + 'person/gender' => 'gender', + 'contact/postalCode/home' => 'postcode', + 'contact/country/home' => 'country', + 'pref/language' => 'language', + 'pref/timezone' => 'timezone', + ); + + function __construct() + { + $this->trustRoot = (!empty($_SERVER['HTTPS']) ? 'https' : 'http') . '://' . $_SERVER['HTTP_HOST']; + $uri = $_SERVER['REQUEST_URI']; + $uri = strpos($uri, '?') ? substr($uri, 0, strpos($uri, '?')) : $uri; + $this->returnUrl = $this->trustRoot . $uri; + + $this->data = $_POST + $_GET; # OPs may send data as POST or GET. + } + + function __set($name, $value) + { + switch ($name) { + case 'identity': + if (strlen($value = trim((String) $value))) { + if (preg_match('#^xri:/*#i', $value, $m)) { + $value = substr($value, strlen($m[0])); + } elseif (!preg_match('/^(?:[=@+\$!\(]|https?:)/i', $value)) { + $value = "http://$value"; + } + if (preg_match('#^https?://[^/]+$#i', $value, $m)) { + $value .= '/'; + } + } + $this->$name = $this->claimed_id = $value; + break; + case 'trustRoot': + case 'realm': + $this->trustRoot = trim($value); + } + } + + function __get($name) + { + switch ($name) { + case 'identity': + # We return claimed_id instead of identity, + # because the developer should see the claimed identifier, + # i.e. what he set as identity, not the op-local identifier (which is what we verify) + return $this->claimed_id; + case 'trustRoot': + case 'realm': + return $this->trustRoot; + } + } + + /** + * Checks if the server specified in the url exists. + * + * @param $url url to check + * @return true, if the server exists; false otherwise + */ + function hostExists($url) + { + if (strpos($url, '/') === false) { + $server = $url; + } else { + $server = @parse_url($url, PHP_URL_HOST); + } + + if (!$server) { + return false; + } + + return !!gethostbynamel($server); + } + + protected function request_curl($url, $method='GET', $params=array()) + { + $params = http_build_query($params, '', '&'); + $curl = curl_init($url . ($method == 'GET' && $params ? '?' . $params : '')); + curl_setopt($curl, CURLOPT_FOLLOWLOCATION, true); + curl_setopt($curl, CURLOPT_HEADER, false); + curl_setopt($curl, CURLOPT_SSL_VERIFYPEER, false); + curl_setopt($curl, CURLOPT_RETURNTRANSFER, true); + curl_setopt($curl, CURLOPT_HTTPHEADER, array('Accept: application/xrds+xml, */*')); + + if($this->verify_perr !== null) { + curl_setopt($curl, CURLOPT_SSL_VERIFYPEER, $this->verify_peer); + if($this->capath) { + curl_setopt($curl, CURLOPT_CAPATH, $this->capath); + } + } + + if ($method == 'POST') { + curl_setopt($curl, CURLOPT_POST, true); + curl_setopt($curl, CURLOPT_POSTFIELDS, $params); + } elseif ($method == 'HEAD') { + curl_setopt($curl, CURLOPT_HEADER, true); + curl_setopt($curl, CURLOPT_NOBODY, true); + } else { + curl_setopt($curl, CURLOPT_HTTPGET, true); + } + $response = curl_exec($curl); + + if($method == 'HEAD') { + $headers = array(); + foreach(explode("\n", $response) as $header) { + $pos = strpos($header,':'); + $name = strtolower(trim(substr($header, 0, $pos))); + $headers[$name] = trim(substr($header, $pos+1)); + } + + # Updating claimed_id in case of redirections. + $effective_url = curl_getinfo($curl, CURLINFO_EFFECTIVE_URL); + if($effective_url != $url) { + $this->identity = $this->claimed_id = $effective_url; + } + + return $headers; + } + + if (curl_errno($curl)) { + throw new ErrorException(curl_error($curl), curl_errno($curl)); + } + + return $response; + } + + protected function request_streams($url, $method='GET', $params=array()) + { + if(!$this->hostExists($url)) { + throw new ErrorException('Invalid request.'); + } + + $params = http_build_query($params, '', '&'); + switch($method) { + case 'GET': + $opts = array( + 'http' => array( + 'method' => 'GET', + 'header' => 'Accept: application/xrds+xml, */*', + 'ignore_errors' => true, + ) + ); + $url = $url . ($params ? '?' . $params : ''); + break; + case 'POST': + $opts = array( + 'http' => array( + 'method' => 'POST', + 'header' => 'Content-type: application/x-www-form-urlencoded', + 'content' => $params, + 'ignore_errors' => true, + ) + ); + break; + case 'HEAD': + # We want to send a HEAD request, + # but since get_headers doesn't accept $context parameter, + # we have to change the defaults. + $default = stream_context_get_options(stream_context_get_default()); + stream_context_get_default( + array('http' => array( + 'method' => 'HEAD', + 'header' => 'Accept: application/xrds+xml, */*', + 'ignore_errors' => true, + )) + ); + + $url = $url . ($params ? '?' . $params : ''); + $headers_tmp = get_headers ($url); + if(!$headers_tmp) { + return array(); + } + + # Parsing headers. + $headers = array(); + foreach($headers_tmp as $header) { + $pos = strpos($header,':'); + $name = strtolower(trim(substr($header, 0, $pos))); + $headers[$name] = trim(substr($header, $pos+1)); + + # Following possible redirections. The point is just to have + # claimed_id change with them, because get_headers() will + # follow redirections automatically. + # We ignore redirections with relative paths. + # If any known provider uses them, file a bug report. + if($name == 'location') { + if(strpos($headers[$name], 'http') === 0) { + $this->identity = $this->claimed_id = $headers[$name]; + } elseif($headers[$name][0] == '/') { + $parsed_url = parse_url($this->claimed_id); + $this->identity = + $this->claimed_id = $parsed_url['scheme'] . '://' + . $parsed_url['host'] + . $headers[$name]; + } + } + } + + # And restore them. + stream_context_get_default($default); + return $headers; + } + + if($this->verify_peer) { + $opts += array('ssl' => array( + 'verify_peer' => true, + 'capath' => $this->capath, + )); + } + + $context = stream_context_create ($opts); + + return file_get_contents($url, false, $context); + } + + protected function request($url, $method='GET', $params=array()) + { + if(function_exists('curl_init') && !ini_get('safe_mode')) { + return $this->request_curl($url, $method, $params); + } + return $this->request_streams($url, $method, $params); + } + + protected function build_url($url, $parts) + { + if (isset($url['query'], $parts['query'])) { + $parts['query'] = $url['query'] . '&' . $parts['query']; + } + + $url = $parts + $url; + $url = $url['scheme'] . '://' + . (empty($url['username'])?'' + :(empty($url['password'])? "{$url['username']}@" + :"{$url['username']}:{$url['password']}@")) + . $url['host'] + . (empty($url['port'])?'':":{$url['port']}") + . (empty($url['path'])?'':$url['path']) + . (empty($url['query'])?'':"?{$url['query']}") + . (empty($url['fragment'])?'':":{$url['fragment']}"); + return $url; + } + + /** + * Helper function used to scan for <meta>/<link> tags and extract information + * from them + */ + protected function htmlTag($content, $tag, $attrName, $attrValue, $valueName) + { + preg_match_all("#<{$tag}[^>]*$attrName=['\"].*?$attrValue.*?['\"][^>]*$valueName=['\"](.+?)['\"][^>]*/?>#i", $content, $matches1); + preg_match_all("#<{$tag}[^>]*$valueName=['\"](.+?)['\"][^>]*$attrName=['\"].*?$attrValue.*?['\"][^>]*/?>#i", $content, $matches2); + + $result = array_merge($matches1[1], $matches2[1]); + return empty($result)?false:$result[0]; + } + + /** + * Performs Yadis and HTML discovery. Normally not used. + * @param $url Identity URL. + * @return String OP Endpoint (i.e. OpenID provider address). + * @throws ErrorException + */ + function discover($url) + { + if (!$url) throw new ErrorException('No identity supplied.'); + # Use xri.net proxy to resolve i-name identities + if (!preg_match('#^https?:#', $url)) { + $url = "https://xri.net/$url"; + } + + # We save the original url in case of Yadis discovery failure. + # It can happen when we'll be lead to an XRDS document + # which does not have any OpenID2 services. + $originalUrl = $url; + + # A flag to disable yadis discovery in case of failure in headers. + $yadis = true; + + # We'll jump a maximum of 5 times, to avoid endless redirections. + for ($i = 0; $i < 5; $i ++) { + if ($yadis) { + $headers = $this->request($url, 'HEAD'); + + $next = false; + if (isset($headers['x-xrds-location'])) { + $url = $this->build_url(parse_url($url), parse_url(trim($headers['x-xrds-location']))); + $next = true; + } + + if (isset($headers['content-type']) + && strpos($headers['content-type'], 'application/xrds+xml') !== false + ) { + # Found an XRDS document, now let's find the server, and optionally delegate. + $content = $this->request($url, 'GET'); + + preg_match_all('#<Service.*?>(.*?)</Service>#s', $content, $m); + foreach($m[1] as $content) { + $content = ' ' . $content; # The space is added, so that strpos doesn't return 0. + + # OpenID 2 + $ns = preg_quote('http://specs.openid.net/auth/2.0/'); + if(preg_match('#<Type>\s*'.$ns.'(server|signon)\s*</Type>#s', $content, $type)) { + if ($type[1] == 'server') $this->identifier_select = true; + + preg_match('#<URI.*?>(.*)</URI>#', $content, $server); + preg_match('#<(Local|Canonical)ID>(.*)</\1ID>#', $content, $delegate); + if (empty($server)) { + return false; + } + # Does the server advertise support for either AX or SREG? + $this->ax = (bool) strpos($content, '<Type>http://openid.net/srv/ax/1.0</Type>'); + $this->sreg = strpos($content, '<Type>http://openid.net/sreg/1.0</Type>') + || strpos($content, '<Type>http://openid.net/extensions/sreg/1.1</Type>'); + + $server = $server[1]; + if (isset($delegate[2])) $this->identity = trim($delegate[2]); + $this->version = 2; + + $this->server = $server; + return $server; + } + + # OpenID 1.1 + $ns = preg_quote('http://openid.net/signon/1.1'); + if (preg_match('#<Type>\s*'.$ns.'\s*</Type>#s', $content)) { + + preg_match('#<URI.*?>(.*)</URI>#', $content, $server); + preg_match('#<.*?Delegate>(.*)</.*?Delegate>#', $content, $delegate); + if (empty($server)) { + return false; + } + # AX can be used only with OpenID 2.0, so checking only SREG + $this->sreg = strpos($content, '<Type>http://openid.net/sreg/1.0</Type>') + || strpos($content, '<Type>http://openid.net/extensions/sreg/1.1</Type>'); + + $server = $server[1]; + if (isset($delegate[1])) $this->identity = $delegate[1]; + $this->version = 1; + + $this->server = $server; + return $server; + } + } + + $next = true; + $yadis = false; + $url = $originalUrl; + $content = null; + break; + } + if ($next) continue; + + # There are no relevant information in headers, so we search the body. + $content = $this->request($url, 'GET'); + if ($location = $this->htmlTag($content, 'meta', 'http-equiv', 'X-XRDS-Location', 'content')) { + $url = $this->build_url(parse_url($url), parse_url($location)); + continue; + } + } + + if (!$content) $content = $this->request($url, 'GET'); + + # At this point, the YADIS Discovery has failed, so we'll switch + # to openid2 HTML discovery, then fallback to openid 1.1 discovery. + $server = $this->htmlTag($content, 'link', 'rel', 'openid2.provider', 'href'); + $delegate = $this->htmlTag($content, 'link', 'rel', 'openid2.local_id', 'href'); + $this->version = 2; + + if (!$server) { + # The same with openid 1.1 + $server = $this->htmlTag($content, 'link', 'rel', 'openid.server', 'href'); + $delegate = $this->htmlTag($content, 'link', 'rel', 'openid.delegate', 'href'); + $this->version = 1; + } + + if ($server) { + # We found an OpenID2 OP Endpoint + if ($delegate) { + # We have also found an OP-Local ID. + $this->identity = $delegate; + } + $this->server = $server; + return $server; + } + + throw new ErrorException('No servers found!'); + } + throw new ErrorException('Endless redirection!'); + } + + protected function sregParams() + { + $params = array(); + # We always use SREG 1.1, even if the server is advertising only support for 1.0. + # That's because it's fully backwards compatibile with 1.0, and some providers + # advertise 1.0 even if they accept only 1.1. One such provider is myopenid.com + $params['openid.ns.sreg'] = 'http://openid.net/extensions/sreg/1.1'; + if ($this->required) { + $params['openid.sreg.required'] = array(); + foreach ($this->required as $required) { + if (!isset(self::$ax_to_sreg[$required])) continue; + $params['openid.sreg.required'][] = self::$ax_to_sreg[$required]; + } + $params['openid.sreg.required'] = implode(',', $params['openid.sreg.required']); + } + + if ($this->optional) { + $params['openid.sreg.optional'] = array(); + foreach ($this->optional as $optional) { + if (!isset(self::$ax_to_sreg[$optional])) continue; + $params['openid.sreg.optional'][] = self::$ax_to_sreg[$optional]; + } + $params['openid.sreg.optional'] = implode(',', $params['openid.sreg.optional']); + } + return $params; + } + + protected function axParams() + { + $params = array(); + if ($this->required || $this->optional) { + $params['openid.ns.ax'] = 'http://openid.net/srv/ax/1.0'; + $params['openid.ax.mode'] = 'fetch_request'; + $this->aliases = array(); + $counts = array(); + $required = array(); + $optional = array(); + foreach (array('required','optional') as $type) { + foreach ($this->$type as $alias => $field) { + if (is_int($alias)) $alias = strtr($field, '/', '_'); + $this->aliases[$alias] = 'http://axschema.org/' . $field; + if (empty($counts[$alias])) $counts[$alias] = 0; + $counts[$alias] += 1; + ${$type}[] = $alias; + } + } + foreach ($this->aliases as $alias => $ns) { + $params['openid.ax.type.' . $alias] = $ns; + } + foreach ($counts as $alias => $count) { + if ($count == 1) continue; + $params['openid.ax.count.' . $alias] = $count; + } + + # Don't send empty ax.requied and ax.if_available. + # Google and possibly other providers refuse to support ax when one of these is empty. + if($required) { + $params['openid.ax.required'] = implode(',', $required); + } + if($optional) { + $params['openid.ax.if_available'] = implode(',', $optional); + } + } + return $params; + } + + protected function authUrl_v1() + { + $returnUrl = $this->returnUrl; + # If we have an openid.delegate that is different from our claimed id, + # we need to somehow preserve the claimed id between requests. + # The simplest way is to just send it along with the return_to url. + if($this->identity != $this->claimed_id) { + $returnUrl .= (strpos($returnUrl, '?') ? '&' : '?') . 'openid.claimed_id=' . $this->claimed_id; + } + + $params = array( + 'openid.return_to' => $returnUrl, + 'openid.mode' => 'checkid_setup', + 'openid.identity' => $this->identity, + 'openid.trust_root' => $this->trustRoot, + ) + $this->sregParams(); + + return $this->build_url(parse_url($this->server) + , array('query' => http_build_query($params, '', '&'))); + } + + protected function authUrl_v2($identifier_select) + { + $params = array( + 'openid.ns' => 'http://specs.openid.net/auth/2.0', + 'openid.mode' => 'checkid_setup', + 'openid.return_to' => $this->returnUrl, + 'openid.realm' => $this->trustRoot, + ); + if ($this->ax) { + $params += $this->axParams(); + } + if ($this->sreg) { + $params += $this->sregParams(); + } + if (!$this->ax && !$this->sreg) { + # If OP doesn't advertise either SREG, nor AX, let's send them both + # in worst case we don't get anything in return. + $params += $this->axParams() + $this->sregParams(); + } + + if ($identifier_select) { + $params['openid.identity'] = $params['openid.claimed_id'] + = 'http://specs.openid.net/auth/2.0/identifier_select'; + } else { + $params['openid.identity'] = $this->identity; + $params['openid.claimed_id'] = $this->claimed_id; + } + + return $this->build_url(parse_url($this->server) + , array('query' => http_build_query($params, '', '&'))); + } + + /** + * Returns authentication url. Usually, you want to redirect your user to it. + * @return String The authentication url. + * @param String $select_identifier Whether to request OP to select identity for an user in OpenID 2. Does not affect OpenID 1. + * @throws ErrorException + */ + function authUrl($identifier_select = null) + { + if (!$this->server) $this->discover($this->identity); + + if ($this->version == 2) { + if ($identifier_select === null) { + return $this->authUrl_v2($this->identifier_select); + } + return $this->authUrl_v2($identifier_select); + } + return $this->authUrl_v1(); + } + + /** + * Performs OpenID verification with the OP. + * @return Bool Whether the verification was successful. + * @throws ErrorException + */ + function validate() + { + $this->claimed_id = isset($this->data['openid_claimed_id'])?$this->data['openid_claimed_id']:$this->data['openid_identity']; + $params = array( + 'openid.assoc_handle' => $this->data['openid_assoc_handle'], + 'openid.signed' => $this->data['openid_signed'], + 'openid.sig' => $this->data['openid_sig'], + ); + + if (isset($this->data['openid_ns'])) { + # We're dealing with an OpenID 2.0 server, so let's set an ns + # Even though we should know location of the endpoint, + # we still need to verify it by discovery, so $server is not set here + $params['openid.ns'] = 'http://specs.openid.net/auth/2.0'; + } elseif(isset($this->data['openid_claimed_id'])) { + # If it's an OpenID 1 provider, and we've got claimed_id, + # we have to append it to the returnUrl, like authUrl_v1 does. + $this->returnUrl .= (strpos($this->returnUrl, '?') ? '&' : '?') + . 'openid.claimed_id=' . $this->claimed_id; + } + + if ($this->data['openid_return_to'] != $this->returnUrl) { + # The return_to url must match the url of current request. + # I'm assuing that noone will set the returnUrl to something that doesn't make sense. + return false; + } + + $server = $this->discover($this->claimed_id); + + foreach (explode(',', $this->data['openid_signed']) as $item) { + # Checking whether magic_quotes_gpc is turned on, because + # the function may fail if it is. For example, when fetching + # AX namePerson, it might containg an apostrophe, which will be escaped. + # In such case, validation would fail, since we'd send different data than OP + # wants to verify. stripslashes() should solve that problem, but we can't + # use it when magic_quotes is off. + $value = $this->data['openid_' . str_replace('.','_',$item)]; + $params['openid.' . $item] = get_magic_quotes_gpc() ? stripslashes($value) : $value; + + } + + $params['openid.mode'] = 'check_authentication'; + + $response = $this->request($server, 'POST', $params); + + return preg_match('/is_valid\s*:\s*true/i', $response); + } + + protected function getAxAttributes() + { + $alias = null; + if (isset($this->data['openid_ns_ax']) + && $this->data['openid_ns_ax'] != 'http://openid.net/srv/ax/1.0' + ) { # It's the most likely case, so we'll check it before + $alias = 'ax'; + } else { + # 'ax' prefix is either undefined, or points to another extension, + # so we search for another prefix + foreach ($this->data as $key => $val) { + if (substr($key, 0, strlen('openid_ns_')) == 'openid_ns_' + && $val == 'http://openid.net/srv/ax/1.0' + ) { + $alias = substr($key, strlen('openid_ns_')); + break; + } + } + } + if (!$alias) { + # An alias for AX schema has not been found, + # so there is no AX data in the OP's response + return array(); + } + + $attributes = array(); + foreach ($this->data as $key => $value) { + $keyMatch = 'openid_' . $alias . '_value_'; + if (substr($key, 0, strlen($keyMatch)) != $keyMatch) { + continue; + } + $key = substr($key, strlen($keyMatch)); + if (!isset($this->data['openid_' . $alias . '_type_' . $key])) { + # OP is breaking the spec by returning a field without + # associated ns. This shouldn't happen, but it's better + # to check, than cause an E_NOTICE. + continue; + } + $key = substr($this->data['openid_' . $alias . '_type_' . $key], + strlen('http://axschema.org/')); + $attributes[$key] = $value; + } + return $attributes; + } + + protected function getSregAttributes() + { + $attributes = array(); + $sreg_to_ax = array_flip(self::$ax_to_sreg); + foreach ($this->data as $key => $value) { + $keyMatch = 'openid_sreg_'; + if (substr($key, 0, strlen($keyMatch)) != $keyMatch) { + continue; + } + $key = substr($key, strlen($keyMatch)); + if (!isset($sreg_to_ax[$key])) { + # The field name isn't part of the SREG spec, so we ignore it. + continue; + } + $attributes[$sreg_to_ax[$key]] = $value; + } + return $attributes; + } + + /** + * Gets AX/SREG attributes provided by OP. should be used only after successful validaton. + * Note that it does not guarantee that any of the required/optional parameters will be present, + * or that there will be no other attributes besides those specified. + * In other words. OP may provide whatever information it wants to. + * * SREG names will be mapped to AX names. + * * @return Array Array of attributes with keys being the AX schema names, e.g. 'contact/email' + * @see http://www.axschema.org/types/ + */ + function getAttributes() + { + if (isset($this->data['openid_ns']) + && $this->data['openid_ns'] == 'http://specs.openid.net/auth/2.0' + ) { # OpenID 2.0 + # We search for both AX and SREG attributes, with AX taking precedence. + return $this->getAxAttributes() + $this->getSregAttributes(); + } + return $this->getSregAttributes(); + } +} |