includes/auth/AuthenticationRequest.php

   1 <?php
   2 /**
   3  * Authentication request value object
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @ingroup Auth
  22  */
  23
  24 namespace MediaWiki\Auth;
  25
  26 use Message;
  27
  28 /**
  29  * This is a value object for authentication requests.
  30  *
  31  * An AuthenticationRequest represents a set of form fields that are needed on
  32  * and provided from a login, account creation, password change or similar form.
  33  *
  34  * @ingroup Auth
  35  * @since 1.27
  36  */
  37 abstract class AuthenticationRequest {
  38
  39         /** Indicates that the request is not required for authentication to proceed. */
  40         const OPTIONAL = 0;
  41
  42         /** Indicates that the request is required for authentication to proceed.
  43          * This will only be used for UI purposes; it is the authentication providers'
  44          * responsibility to verify that all required requests are present.
  45          */
  46         const REQUIRED = 1;
  47
  48         /** Indicates that the request is required by a primary authentication
  49          * provider. Since the user can choose which primary to authenticate with,
  50          * the request might or might not end up being actually required. */
  51         const PRIMARY_REQUIRED = 2;
  52
  53         /** @var string|null The AuthManager::ACTION_* constant this request was
  54          * created to be used for. The *_CONTINUE constants are not used here, the
  55          * corresponding "begin" constant is used instead.
  56          */
  57         public $action = null;
  58
  59         /** @var int For login, continue, and link actions, one of self::OPTIONAL,
  60          * self::REQUIRED, or self::PRIMARY_REQUIRED */
  61         public $required = self::REQUIRED;
  62
  63         /** @var string|null Return-to URL, in case of redirect */
  64         public $returnToUrl = null;
  65
  66         /** @var string|null Username. See AuthenticationProvider::getAuthenticationRequests()
  67          * for details of what this means and how it behaves. */
  68         public $username = null;
  69
  70         /**
  71          * Supply a unique key for deduplication
  72          *
  73          * When the AuthenticationRequests instances returned by the providers are
  74          * merged, the value returned here is used for keeping only one copy of
  75          * duplicate requests.
  76          *
  77          * Subclasses should override this if multiple distinct instances would
  78          * make sense, i.e. the request class has internal state of some sort.
  79          *
  80          * This value might be exposed to the user in web forms so it should not
  81          * contain private information.
  82          *
  83          * @return string
  84          */
  85         public function getUniqueId() {
  86                 return get_called_class();
  87         }
  88
  89         /**
  90          * Fetch input field info
  91          *
  92          * The field info is an associative array mapping field names to info
  93          * arrays. The info arrays have the following keys:
  94          *  - type: (string) Type of input. Types and equivalent HTML widgets are:
  95          *     - string: <input type="text">
  96          *     - password: <input type="password">
  97          *     - select: <select>
  98          *     - checkbox: <input type="checkbox">
  99          *     - multiselect: More a grid of checkboxes than <select multi>
 100          *     - button: <input type="submit"> (uses 'label' as button text)
 101          *     - hidden: Not visible to the user, but needs to be preserved for the next request
 102          *     - null: No widget, just display the 'label' message.
 103          *  - options: (array) Maps option values to Messages for the
 104          *      'select' and 'multiselect' types.
 105          *  - value: (string) Value (for 'null' and 'hidden') or default value (for other types).
 106          *  - label: (Message) Text suitable for a label in an HTML form
 107          *  - help: (Message) Text suitable as a description of what the field is
 108          *  - optional: (bool) If set and truthy, the field may be left empty
 109          *  - sensitive: (bool) If set and truthy, the field is considered sensitive. Code using the
 110          *      request should avoid exposing the value of the field.
 111          *  - skippable: (bool) If set and truthy, the client is free to hide this
 112          *      field from the user to streamline the workflow. If all fields are
 113          *      skippable (except possibly a single button), no user interaction is
 114          *      required at all.
 115          *
 116          * All AuthenticationRequests are populated from the same data, so most of the time you'll
 117          * want to prefix fields names with something unique to the extension/provider (although
 118          * in some cases sharing the field with other requests is the right thing to do, e.g. for
 119          * a 'password' field).
 120          *
 121          * @return array As above
 122          */
 123         abstract public function getFieldInfo();
 124
 125         /**
 126          * Returns metadata about this request.
 127          *
 128          * This is mainly for the benefit of API clients which need more detailed render hints
 129          * than what's available through getFieldInfo(). Semantics are unspecified and left to the
 130          * individual subclasses, but the contents of the array should be primitive types so that they
 131          * can be transformed into JSON or similar formats.
 132          *
 133          * @return array A (possibly nested) array with primitive types
 134          */
 135         public function getMetadata() {
 136                 return [];
 137         }
 138
 139         /**
 140          * Initialize form submitted form data.
 141          *
 142          * The default behavior is to to check for each key of self::getFieldInfo()
 143          * in the submitted data, and copy the value - after type-appropriate transformations -
 144          * to $this->$key. Most subclasses won't need to override this; if you do override it,
 145          * make sure to always return false if self::getFieldInfo() returns an empty array.
 146          *
 147          * @param array $data Submitted data as an associative array (keys will correspond
 148          *   to getFieldInfo())
 149          * @return bool Whether the request data was successfully loaded
 150          */
 151         public function loadFromSubmission( array $data ) {
 152                 $fields = array_filter( $this->getFieldInfo(), function ( $info ) {
 153                         return $info['type'] !== 'null';
 154                 } );
 155                 if ( !$fields ) {
 156                         return false;
 157                 }
 158
 159                 foreach ( $fields as $field => $info ) {
 160                         // Checkboxes and buttons are special. Depending on the method used
 161                         // to populate $data, they might be unset meaning false or they
 162                         // might be boolean. Further, image buttons might submit the
 163                         // coordinates of the click rather than the expected value.
 164                         if ( $info['type'] === 'checkbox' || $info['type'] === 'button' ) {
 165                                 $this->$field = isset( $data[$field] ) && $data[$field] !== false
 166                                         || isset( $data["{$field}_x"] ) && $data["{$field}_x"] !== false;
 167                                 if ( !$this->$field && empty( $info['optional'] ) ) {
 168                                         return false;
 169                                 }
 170                                 continue;
 171                         }
 172
 173                         // Multiselect are too, slightly
 174                         if ( !isset( $data[$field] ) && $info['type'] === 'multiselect' ) {
 175                                 $data[$field] = [];
 176                         }
 177
 178                         if ( !isset( $data[$field] ) ) {
 179                                 return false;
 180                         }
 181                         if ( $data[$field] === '' || $data[$field] === [] ) {
 182                                 if ( empty( $info['optional'] ) ) {
 183                                         return false;
 184                                 }
 185                         } else {
 186                                 switch ( $info['type'] ) {
 187                                         case 'select':
 188                                                 if ( !isset( $info['options'][$data[$field]] ) ) {
 189                                                         return false;
 190                                                 }
 191                                                 break;
 192
 193                                         case 'multiselect':
 194                                                 $data[$field] = (array)$data[$field];
 195                                                 $allowed = array_keys( $info['options'] );
 196                                                 if ( array_diff( $data[$field], $allowed ) !== [] ) {
 197                                                         return false;
 198                                                 }
 199                                                 break;
 200                                 }
 201                         }
 202
 203                         $this->$field = $data[$field];
 204                 }
 205
 206                 return true;
 207         }
 208
 209         /**
 210          * Describe the credentials represented by this request
 211          *
 212          * This is used on requests returned by
 213          * AuthenticationProvider::getAuthenticationRequests() for ACTION_LINK
 214          * and ACTION_REMOVE and for requests returned in
 215          * AuthenticationResponse::$linkRequest to create useful user interfaces.
 216          *
 217          * @return Message[] with the following keys:
 218          *  - provider: A Message identifying the service that provides
 219          *    the credentials, e.g. the name of the third party authentication
 220          *    service.
 221          *  - account: A Message identifying the credentials themselves,
 222          *    e.g. the email address used with the third party authentication
 223          *    service.
 224          */
 225         public function describeCredentials() {
 226                 return [
 227                         'provider' => new \RawMessage( '$1', [ get_called_class() ] ),
 228                         'account' => new \RawMessage( '$1', [ $this->getUniqueId() ] ),
 229                 ];
 230         }
 231
 232         /**
 233          * Update a set of requests with form submit data, discarding ones that fail
 234          * @param AuthenticationRequest[] $reqs
 235          * @param array $data
 236          * @return AuthenticationRequest[]
 237          */
 238         public static function loadRequestsFromSubmission( array $reqs, array $data ) {
 239                 return array_values( array_filter( $reqs, function ( $req ) use ( $data ) {
 240                         return $req->loadFromSubmission( $data );
 241                 } ) );
 242         }
 243
 244         /**
 245          * Select a request by class name.
 246          * @param AuthenticationRequest[] $reqs
 247          * @param string $class Class name
 248          * @param bool $allowSubclasses If true, also returns any request that's a subclass of the given
 249          *   class.
 250          * @return AuthenticationRequest|null Returns null if there is not exactly
 251          *  one matching request.
 252          */
 253         public static function getRequestByClass( array $reqs, $class, $allowSubclasses = false ) {
 254                 $requests = array_filter( $reqs, function ( $req ) use ( $class, $allowSubclasses ) {
 255                         if ( $allowSubclasses ) {
 256                                 return is_a( $req, $class, false );
 257                         } else {
 258                                 return get_class( $req ) === $class;
 259                         }
 260                 } );
 261                 return count( $requests ) === 1 ? reset( $requests ) : null;
 262         }
 263
 264         /**
 265          * Get the username from the set of requests
 266          *
 267          * Only considers requests that have a "username" field.
 268          *
 269          * @param AuthenticationRequest[] $reqs
 270          * @return string|null
 271          * @throws \UnexpectedValueException If multiple different usernames are present.
 272          */
 273         public static function getUsernameFromRequests( array $reqs ) {
 274                 $username = null;
 275                 $otherClass = null;
 276                 foreach ( $reqs as $req ) {
 277                         $info = $req->getFieldInfo();
 278                         if ( $info && array_key_exists( 'username', $info ) && $req->username !== null ) {
 279                                 if ( $username === null ) {
 280                                         $username = $req->username;
 281                                         $otherClass = get_class( $req );
 282                                 } elseif ( $username !== $req->username ) {
 283                                         $requestClass = get_class( $req );
 284                                         throw new \UnexpectedValueException( "Conflicting username fields: \"{$req->username}\" from "
 285                                                 . "$requestClass::\$username vs. \"$username\" from $otherClass::\$username" );
 286                                 }
 287                         }
 288                 }
 289                 return $username;
 290         }
 291
 292         /**
 293          * Merge the output of multiple AuthenticationRequest::getFieldInfo() calls.
 294          * @param AuthenticationRequest[] $reqs
 295          * @return array
 296          * @throws \UnexpectedValueException If fields cannot be merged
 297          */
 298         public static function mergeFieldInfo( array $reqs ) {
 299                 $merged = [];
 300
 301                 // fields that are required by some primary providers but not others are not actually required
 302                 $primaryRequests = array_filter( $reqs, function ( $req ) {
 303                         return $req->required === AuthenticationRequest::PRIMARY_REQUIRED;
 304                 } );
 305                 $sharedRequiredPrimaryFields = array_reduce( $primaryRequests, function ( $shared, $req ) {
 306                         $required = array_keys( array_filter( $req->getFieldInfo(), function ( $options ) {
 307                                 return empty( $options['optional'] );
 308                         } ) );
 309                         if ( $shared === null ) {
 310                                 return $required;
 311                         } else {
 312                                 return array_intersect( $shared, $required );
 313                         }
 314                 }, null );
 315
 316                 foreach ( $reqs as $req ) {
 317                         $info = $req->getFieldInfo();
 318                         if ( !$info ) {
 319                                 continue;
 320                         }
 321
 322                         foreach ( $info as $name => $options ) {
 323                                 if (
 324                                         // If the request isn't required, its fields aren't required either.
 325                                         $req->required === self::OPTIONAL
 326                                         // If there is a primary not requiring this field, no matter how many others do,
 327                                         // authentication can proceed without it.
 328                                         || $req->required === self::PRIMARY_REQUIRED
 329                                                 && !in_array( $name, $sharedRequiredPrimaryFields, true )
 330                                 ) {
 331                                         $options['optional'] = true;
 332                                 } else {
 333                                         $options['optional'] = !empty( $options['optional'] );
 334                                 }
 335
 336                                 $options['sensitive'] = !empty( $options['sensitive'] );
 337
 338                                 if ( !array_key_exists( $name, $merged ) ) {
 339                                         $merged[$name] = $options;
 340                                 } elseif ( $merged[$name]['type'] !== $options['type'] ) {
 341                                         throw new \UnexpectedValueException( "Field type conflict for \"$name\", " .
 342                                                 "\"{$merged[$name]['type']}\" vs \"{$options['type']}\""
 343                                         );
 344                                 } else {
 345                                         if ( isset( $options['options'] ) ) {
 346                                                 if ( isset( $merged[$name]['options'] ) ) {
 347                                                         $merged[$name]['options'] += $options['options'];
 348                                                 } else {
 349                                                         // @codeCoverageIgnoreStart
 350                                                         $merged[$name]['options'] = $options['options'];
 351                                                         // @codeCoverageIgnoreEnd
 352                                                 }
 353                                         }
 354
 355                                         $merged[$name]['optional'] = $merged[$name]['optional'] && $options['optional'];
 356                                         $merged[$name]['sensitive'] = $merged[$name]['sensitive'] || $options['sensitive'];
 357
 358                                         // No way to merge 'value', 'image', 'help', or 'label', so just use
 359                                         // the value from the first request.
 360                                 }
 361                         }
 362                 }
 363
 364                 return $merged;
 365         }
 366
 367         /**
 368          * Implementing this mainly for use from the unit tests.
 369          * @param array $data
 370          * @return AuthenticationRequest
 371          */
 372         public static function __set_state( $data ) {
 373                 $ret = new static();
 374                 foreach ( $data as $k => $v ) {
 375                         $ret->$k = $v;
 376                 }
 377                 return $ret;
 378         }
 379 }