<?php
 
/**
 * Implements the OpenID attribute exchange specification, version 1.0
 * as of svn revision 370 from openid.net svn.
 *
 * @package OpenID
 */
 
/**
 * Require utility classes and functions for the consumer.
 */
require_once "Auth/OpenID/Extension.php";
require_once "Auth/OpenID/Message.php";
require_once "Auth/OpenID/TrustRoot.php";
 
define('Auth_OpenID_AX_NS_URI',
       'http://openid.net/srv/ax/1.0');
 
// Use this as the 'count' value for an attribute in a FetchRequest to
// ask for as many values as the OP can provide.
define('Auth_OpenID_AX_UNLIMITED_VALUES', 'unlimited');
 
// Minimum supported alias length in characters.  Here for
// completeness.
define('Auth_OpenID_AX_MINIMUM_SUPPORTED_ALIAS_LENGTH', 32);
 
/**
 * AX utility class.
 *
 * @package OpenID
 */
class Auth_OpenID_AX {
    /**
     * @param mixed $thing Any object which may be an
     * Auth_OpenID_AX_Error object.
     *
     * @return bool true if $thing is an Auth_OpenID_AX_Error; false
     * if not.
     */
    static function isError($thing)
    {
        return is_a($thing, 'Auth_OpenID_AX_Error');
    }
}
 
/**
 * Check an alias for invalid characters; raise AXError if any are
 * found.  Return None if the alias is valid.
 */
function Auth_OpenID_AX_checkAlias($alias)
{
  if (strpos($alias, ',') !== false) {
      return new Auth_OpenID_AX_Error(sprintf(
                   "Alias %s must not contain comma", $alias));
  }
  if (strpos($alias, '.') !== false) {
      return new Auth_OpenID_AX_Error(sprintf(
                   "Alias %s must not contain period", $alias));
  }
 
  return true;
}
 
/**
 * Results from data that does not meet the attribute exchange 1.0
 * specification
 *
 * @package OpenID
 */
class Auth_OpenID_AX_Error {
    function Auth_OpenID_AX_Error($message=null)
    {
        $this->message = $message;
    }
}
 
/**
 * Abstract class containing common code for attribute exchange
 * messages.
 *
 * @package OpenID
 */
class Auth_OpenID_AX_Message extends Auth_OpenID_Extension {
    /**
     * ns_alias: The preferred namespace alias for attribute exchange
     * messages
     */
    var $ns_alias = 'ax';
 
    /**
     * mode: The type of this attribute exchange message. This must be
     * overridden in subclasses.
     */
    var $mode = null;
 
    var $ns_uri = Auth_OpenID_AX_NS_URI;
 
    /**
     * Return Auth_OpenID_AX_Error if the mode in the attribute
     * exchange arguments does not match what is expected for this
     * class; true otherwise.
     *
     * @access private
     */
    function _checkMode($ax_args)
    {
        $mode = Auth_OpenID::arrayGet($ax_args, 'mode');
        if ($mode != $this->mode) {
            return new Auth_OpenID_AX_Error(
                            sprintf(
                                    "Expected mode '%s'; got '%s'",
                                    $this->mode, $mode));
        }
 
        return true;
    }
 
    /**
     * Return a set of attribute exchange arguments containing the
     * basic information that must be in every attribute exchange
     * message.
     *
     * @access private
     */
    function _newArgs()
    {
        return array('mode' => $this->mode);
    }
}
 
/**
 * Represents a single attribute in an attribute exchange
 * request. This should be added to an AXRequest object in order to
 * request the attribute.
 *
 * @package OpenID
 */
class Auth_OpenID_AX_AttrInfo {
    /**
     * Construct an attribute information object.  Do not call this
     * directly; call make(...) instead.
     *
     * @param string $type_uri The type URI for this attribute.
     *
     * @param int $count The number of values of this type to request.
     *
     * @param bool $required Whether the attribute will be marked as
     * required in the request.
     *
     * @param string $alias The name that should be given to this
     * attribute in the request.
     */
    function Auth_OpenID_AX_AttrInfo($type_uri, $count, $required,
                                     $alias)
    {
        /**
         * required: Whether the attribute will be marked as required
         * when presented to the subject of the attribute exchange
         * request.
         */
        $this->required = $required;
 
        /**
         * count: How many values of this type to request from the
         * subject. Defaults to one.
         */
        $this->count = $count;
 
        /**
         * type_uri: The identifier that determines what the attribute
         * represents and how it is serialized. For example, one type
         * URI representing dates could represent a Unix timestamp in
         * base 10 and another could represent a human-readable
         * string.
         */
        $this->type_uri = $type_uri;
 
        /**
         * alias: The name that should be given to this attribute in
         * the request. If it is not supplied, a generic name will be
         * assigned. For example, if you want to call a Unix timestamp
         * value 'tstamp', set its alias to that value. If two
         * attributes in the same message request to use the same
         * alias, the request will fail to be generated.
         */
        $this->alias = $alias;
    }
 
    /**
     * Construct an attribute information object.  For parameter
     * details, see the constructor.
     */
    static function make($type_uri, $count=1, $required=false,
                  $alias=null)
    {
        if ($alias !== null) {
            $result = Auth_OpenID_AX_checkAlias($alias);
 
            if (Auth_OpenID_AX::isError($result)) {
                return $result;
            }
        }
 
        return new Auth_OpenID_AX_AttrInfo($type_uri, $count, $required,
                                           $alias);
    }
 
    /**
     * When processing a request for this attribute, the OP should
     * call this method to determine whether all available attribute
     * values were requested.  If self.count == UNLIMITED_VALUES, this
     * returns True.  Otherwise this returns False, in which case
     * self.count is an integer.
    */
    function wantsUnlimitedValues()
    {
        return $this->count === Auth_OpenID_AX_UNLIMITED_VALUES;
    }
}
 
/**
 * Given a namespace mapping and a string containing a comma-separated
 * list of namespace aliases, return a list of type URIs that
 * correspond to those aliases.
 *
 * @param $namespace_map The mapping from namespace URI to alias
 * @param $alias_list_s The string containing the comma-separated
 * list of aliases. May also be None for convenience.
 *
 * @return $seq The list of namespace URIs that corresponds to the
 * supplied list of aliases. If the string was zero-length or None, an
 * empty list will be returned.
 *
 * return null If an alias is present in the list of aliases but
 * is not present in the namespace map.
 */
function Auth_OpenID_AX_toTypeURIs($namespace_map, $alias_list_s)
{
    $uris = array();
 
    if ($alias_list_s) {
        foreach (explode(',', $alias_list_s) as $alias) {
            $type_uri = $namespace_map->getNamespaceURI($alias);
            if ($type_uri === null) {
                // raise KeyError(
                // 'No type is defined for attribute name %r' % (alias,))
                return new Auth_OpenID_AX_Error(
                  sprintf('No type is defined for attribute name %s',
                          $alias)
                  );
            } else {
                $uris[] = $type_uri;
            }
        }
    }
 
    return $uris;
}
 
/**
 * An attribute exchange 'fetch_request' message. This message is sent
 * by a relying party when it wishes to obtain attributes about the
 * subject of an OpenID authentication request.
 *
 * @package OpenID
 */
class Auth_OpenID_AX_FetchRequest extends Auth_OpenID_AX_Message {
 
    var $mode = 'fetch_request';
 
    function Auth_OpenID_AX_FetchRequest($update_url=null)
    {
        /**
         * requested_attributes: The attributes that have been
         * requested thus far, indexed by the type URI.
         */
        $this->requested_attributes = array();
 
        /**
         * update_url: A URL that will accept responses for this
         * attribute exchange request, even in the absence of the user
         * who made this request.
        */
        $this->update_url = $update_url;
    }
 
    /**
     * Add an attribute to this attribute exchange request.
     *
     * @param attribute: The attribute that is being requested
     * @return true on success, false when the requested attribute is
     * already present in this fetch request.
     */
    function add($attribute)
    {
        if ($this->contains($attribute->type_uri)) {
            return new Auth_OpenID_AX_Error(
              sprintf("The attribute %s has already been requested",
                      $attribute->type_uri));
        }
 
        $this->requested_attributes[$attribute->type_uri] = $attribute;
 
        return true;
    }
 
    /**
     * Get the serialized form of this attribute fetch request.
     *
     * @returns Auth_OpenID_AX_FetchRequest The fetch request message parameters
     */
    function getExtensionArgs()
    {
        $aliases = new Auth_OpenID_NamespaceMap();
 
        $required = array();
        $if_available = array();
 
        $ax_args = $this->_newArgs();
 
        foreach ($this->requested_attributes as $type_uri => $attribute) {
            if ($attribute->alias === null) {
                $alias = $aliases->add($type_uri);
            } else {
                $alias = $aliases->addAlias($type_uri, $attribute->alias);
 
                if ($alias === null) {
                    return new Auth_OpenID_AX_Error(
                      sprintf("Could not add alias %s for URI %s",
                              $attribute->alias, $type_uri
                      ));
                }
            }
 
            if ($attribute->required) {
                $required[] = $alias;
            } else {
                $if_available[] = $alias;
            }
 
            if ($attribute->count != 1) {
                $ax_args['count.' . $alias] = strval($attribute->count);
            }
 
            $ax_args['type.' . $alias] = $type_uri;
        }
 
        if ($required) {
            $ax_args['required'] = implode(',', $required);
        }
 
        if ($if_available) {
            $ax_args['if_available'] = implode(',', $if_available);
        }
 
        return $ax_args;
    }
 
    /**
     * Get the type URIs for all attributes that have been marked as
     * required.
     *
     * @return A list of the type URIs for attributes that have been
     * marked as required.
     */
    function getRequiredAttrs()
    {
        $required = array();
        foreach ($this->requested_attributes as $type_uri => $attribute) {
            if ($attribute->required) {
                $required[] = $type_uri;
            }
        }
 
        return $required;
    }
 
    /**
     * Extract a FetchRequest from an OpenID message
     *
     * @param request: The OpenID request containing the attribute
     * fetch request
     *
     * @returns mixed An Auth_OpenID_AX_Error or the
     * Auth_OpenID_AX_FetchRequest extracted from the request message if
     * successful
     */
    static function fromOpenIDRequest($request)
    {
        $m = $request->message;
        $obj = new Auth_OpenID_AX_FetchRequest();
        $ax_args = $m->getArgs($obj->ns_uri);
 
        $result = $obj->parseExtensionArgs($ax_args);
 
        if (Auth_OpenID_AX::isError($result)) {
            return $result;
        }
 
        if ($obj->update_url) {
            // Update URL must match the openid.realm of the
            // underlying OpenID 2 message.
            $realm = $m->getArg(Auth_OpenID_OPENID_NS, 'realm',
                        $m->getArg(
                                  Auth_OpenID_OPENID_NS,
                                  'return_to'));
 
            if (!$realm) {
                $obj = new Auth_OpenID_AX_Error(
                  sprintf("Cannot validate update_url %s " .
                          "against absent realm", $obj->update_url));
            } else if (!Auth_OpenID_TrustRoot::match($realm,
                                                     $obj->update_url)) {
                $obj = new Auth_OpenID_AX_Error(
                  sprintf("Update URL %s failed validation against realm %s",
                          $obj->update_url, $realm));
            }
        }
 
        return $obj;
    }
 
    /**
     * Given attribute exchange arguments, populate this FetchRequest.
     *
     * @return $result Auth_OpenID_AX_Error if the data to be parsed
     * does not follow the attribute exchange specification. At least
     * when 'if_available' or 'required' is not specified for a
     * particular attribute type.  Returns true otherwise.
    */
    function parseExtensionArgs($ax_args)
    {
        $result = $this->_checkMode($ax_args);
        if (Auth_OpenID_AX::isError($result)) {
            return $result;
        }
 
        $aliases = new Auth_OpenID_NamespaceMap();
 
        foreach ($ax_args as $key => $value) {
            if (strpos($key, 'type.') === 0) {
                $alias = substr($key, 5);
                $type_uri = $value;
 
                $alias = $aliases->addAlias($type_uri, $alias);
 
                if ($alias === null) {
                    return new Auth_OpenID_AX_Error(
                      sprintf("Could not add alias %s for URI %s",
                              $alias, $type_uri)
                      );
                }
 
                $count_s = Auth_OpenID::arrayGet($ax_args, 'count.'