* Merged WikiPage::updateRestrictions() and Title::updateTitleProtection() into WikiP...

[mediawiki.git] / includes / specials / SpecialBlock.php

<?php
/**
 * Implements Special:Block
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 * http://www.gnu.org/copyleft/gpl.html
 *
 * @file
 * @ingroup SpecialPage
 */

/**
 * A special page that allows users with 'block' right to block users from
 * editing pages and other actions
 *
 * @ingroup SpecialPage
 */
class SpecialBlock extends FormSpecialPage {
        /** The maximum number of edits a user can have and still be hidden
         * TODO: config setting? */
        const HIDEUSER_CONTRIBLIMIT = 1000;

        /** @var User user to be blocked, as passed either by parameter (url?wpTarget=Foo)
         * or as subpage (Special:Block/Foo) */
        protected $target;

        /// @var Block::TYPE_ constant
        protected $type;

        /// @var  User|String the previous block target
        protected $previousTarget;

        /// @var Bool whether the previous submission of the form asked for HideUser
        protected $requestedHideUser;

        /// @var Bool
        protected $alreadyBlocked;

        /// @var Array
        protected $preErrors = array();

        public function __construct() {
                parent::__construct( 'Block', 'block' );
        }

        /**
         * Checks that the user can unblock themselves if they are trying to do so
         *
         * @param User $user
         * @throws ErrorPageError
         */
        protected function checkExecutePermissions( User $user ) {
                 parent::checkExecutePermissions( $user );

                # bug 15810: blocked admins should have limited access here
                $status = self::checkUnblockSelf( $this->target, $user );
                if ( $status !== true ) {
                        throw new ErrorPageError( 'badaccess', $status );
                }
        }

        /**
         * Handle some magic here
         *
         * @param $par String
         */
        protected function setParameter( $par ) {
                # Extract variables from the request.  Try not to get into a situation where we
                # need to extract *every* variable from the form just for processing here, but
                # there are legitimate uses for some variables
                $request = $this->getRequest();
                list( $this->target, $this->type ) = self::getTargetAndType( $par, $request );
                if ( $this->target instanceof User ) {
                        # Set the 'relevant user' in the skin, so it displays links like Contributions,
                        # User logs, UserRights, etc.
                        $this->getSkin()->setRelevantUser( $this->target );
                }

                list( $this->previousTarget, /*...*/ ) = Block::parseTarget( $request->getVal( 'wpPreviousTarget' ) );
                $this->requestedHideUser = $request->getBool( 'wpHideUser' );
        }

        /**
         * Customizes the HTMLForm a bit
         *
         * @param $form HTMLForm
         */
        protected function alterForm( HTMLForm $form ) {
                $form->setWrapperLegendMsg( 'blockip-legend' );
                $form->setHeaderText( '' );
                $form->setSubmitCallback( array( __CLASS__, 'processUIForm' ) );

                $msg = $this->alreadyBlocked ? 'ipb-change-block' : 'ipbsubmit';
                $form->setSubmitTextMsg( $msg );

                # Don't need to do anything if the form has been posted
                if( !$this->getRequest()->wasPosted() && $this->preErrors ){
                        $s = HTMLForm::formatErrors( $this->preErrors );
                        if( $s ){
                                $form->addHeaderText( Html::rawElement(
                                                'div',
                                                array( 'class' => 'error' ),
                                                $s
                                        ) );
                        }
                }
        }

        /**
         * Get the HTMLForm descriptor array for the block form
         * @return Array
         */
        protected function getFormFields(){
                global $wgBlockAllowsUTEdit;

                $user = $this->getUser();

                $a = array(
                        'Target' => array(
                                'type' => 'text',
                                'label-message' => 'ipadressorusername',
                                'tabindex' => '1',
                                'id' => 'mw-bi-target',
                                'size' => '45',
                                'required' => true,
                                'validation-callback' => array( __CLASS__, 'validateTargetField' ),
                        ),
                        'Expiry' => array(
                                'type' => !count( self::getSuggestedDurations() ) ? 'text' : 'selectorother',
                                'label-message' => 'ipbexpiry',
                                'required' => true,
                                'tabindex' => '2',
                                'options' => self::getSuggestedDurations(),
                                'other' => wfMsg( 'ipbother' ),
                        ),
                        'Reason' => array(
                                'type' => 'selectandother',
                                'label-message' => 'ipbreason',
                                'options-message' => 'ipbreason-dropdown',
                        ),
                        'CreateAccount' => array(
                                'type' => 'check',
                                'label-message' => 'ipbcreateaccount',
                                'default' => true,
                        ),
                );

                if( self::canBlockEmail( $user ) ) {
                        $a['DisableEmail'] = array(
                                'type' => 'check',
                                'label-message' => 'ipbemailban',
                        );
                }

                if( $wgBlockAllowsUTEdit ){
                        $a['DisableUTEdit'] = array(
                                'type' => 'check',
                                'label-message' => 'ipb-disableusertalk',
                                'default' => false,
                        );
                }

                $a['AutoBlock'] = array(
                        'type' => 'check',
                        'label-message' => 'ipbenableautoblock',
                        'default' => true,
                );

                # Allow some users to hide name from block log, blocklist and listusers
                if( $user->isAllowed( 'hideuser' ) ) {
                        $a['HideUser'] = array(
                                'type' => 'check',
                                'label-message' => 'ipbhidename',
                                'cssclass' => 'mw-block-hideuser',
                        );
                }

                # Watchlist their user page? (Only if user is logged in)
                if( $user->isLoggedIn() ) {
                        $a['Watch'] = array(
                                'type' => 'check',
                                'label-message' => 'ipbwatchuser',
                        );
                }

                $a['HardBlock'] = array(
                        'type' => 'check',
                        'label-message' => 'ipb-hardblock',
                        'default' => false,
                );

                # This is basically a copy of the Target field, but the user can't change it, so we
                # can see if the warnings we maybe showed to the user before still apply
                $a['PreviousTarget'] = array(
                        'type' => 'hidden',
                        'default' => false,
                );

                # We'll turn this into a checkbox if we need to
                $a['Confirm'] = array(
                        'type' => 'hidden',
                        'default' => '',
                        'label-message' => 'ipb-confirm',
                );

                $this->maybeAlterFormDefaults( $a );

                return $a;
        }

        /**
         * If the user has already been blocked with similar settings, load that block
         * and change the defaults for the form fields to match the existing settings.
         * @param $fields Array HTMLForm descriptor array
         * @return Bool whether fields were altered (that is, whether the target is
         *     already blocked)
         */
        protected function maybeAlterFormDefaults( &$fields ){
                # This will be overwritten by request data
                $fields['Target']['default'] = (string)$this->target;

                # This won't be
                $fields['PreviousTarget']['default'] = (string)$this->target;

                $block = Block::newFromTarget( $this->target );

                if( $block instanceof Block && !$block->mAuto # The block exists and isn't an autoblock
                        && ( $this->type != Block::TYPE_RANGE # The block isn't a rangeblock
                          || $block->getTarget() == $this->target ) # or if it is, the range is what we're about to block
                        )
                {
                        $fields['HardBlock']['default'] = $block->isHardblock();
                        $fields['CreateAccount']['default'] = $block->prevents( 'createaccount' );
                        $fields['AutoBlock']['default'] = $block->isAutoblocking();

                        if( isset( $fields['DisableEmail'] ) ){
                                $fields['DisableEmail']['default'] = $block->prevents( 'sendemail' );
                        }

                        if( isset( $fields['HideUser'] ) ){
                                $fields['HideUser']['default'] = $block->mHideName;
                        }

                        if( isset( $fields['DisableUTEdit'] ) ){
                                $fields['DisableUTEdit']['default'] = $block->prevents( 'editownusertalk' );
                        }

                        $fields['Reason']['default'] = $block->mReason;

                        if( $this->getRequest()->wasPosted() ){
                                # Ok, so we got a POST submission asking us to reblock a user.  So show the
                                # confirm checkbox; the user will only see it if they haven't previously
                                $fields['Confirm']['type'] = 'check';
                        } else {
                                # We got a target, but it wasn't a POST request, so the user must have gone
                                # to a link like [[Special:Block/User]].  We don't need to show the checkbox
                                # as long as they go ahead and block *that* user
                                $fields['Confirm']['default'] = 1;
                        }

                        if( $block->mExpiry == 'infinity' ) {
                                $fields['Expiry']['default'] = 'indefinite';
                        } else {
                                $fields['Expiry']['default'] = wfTimestamp( TS_RFC2822, $block->mExpiry );
                        }

                        $this->alreadyBlocked = true;
                        $this->preErrors[] = array( 'ipb-needreblock', (string)$block->getTarget() );
                }

                # We always need confirmation to do HideUser
                if( $this->requestedHideUser ){
                        $fields['Confirm']['type'] = 'check';
                        unset( $fields['Confirm']['default'] );
                        $this->preErrors[] = 'ipb-confirmhideuser';
                }

                # Or if the user is trying to block themselves
                if( (string)$this->target === $this->getUser()->getName() ){
                        $fields['Confirm']['type'] = 'check';
                        unset( $fields['Confirm']['default'] );
                        $this->preErrors[] = 'ipb-blockingself';
                }
        }

        /**
         * Add header elements like block log entries, etc.
         */
        protected function preText(){
                $text = $this->msg( 'blockiptext' )->parse();

                $otherBlockMessages = array();
                if( $this->target !== null ) {
                        # Get other blocks, i.e. from GlobalBlocking or TorBlock extension
                        wfRunHooks( 'OtherBlockLogLink', array( &$otherBlockMessages, $this->target ) );

                        if( count( $otherBlockMessages ) ) {
                                $s = Html::rawElement(
                                        'h2',
                                        array(),
                                        wfMsgExt( 'ipb-otherblocks-header', 'parseinline', count( $otherBlockMessages ) )
                                ) . "\n";

                                $list = '';

                                foreach( $otherBlockMessages as $link ) {
                                        $list .= Html::rawElement( 'li', array(), $link ) . "\n";
                                }

                                $s .= Html::rawElement(
                                        'ul',
                                        array( 'class' => 'mw-blockip-alreadyblocked' ),
                                        $list
                                ) . "\n";

                                $text .= $s;
                        }
                }

                return $text;
        }

        /**
         * Add footer elements to the form
         * @return void
         */
        protected function postText(){
                # Link to the user's contributions, if applicable
                if( $this->target instanceof User ){
                        $contribsPage = SpecialPage::getTitleFor( 'Contributions', $this->target->getName() );
                        $links[] = Linker::link(
                                $contribsPage,
                                wfMsgExt( 'ipb-blocklist-contribs', 'escape', $this->target->getName() )
                        );
                }

                # Link to unblock the specified user, or to a blank unblock form
                if( $this->target instanceof User ) {
                        $message = wfMsgExt( 'ipb-unblock-addr', array( 'parseinline' ), $this->target->getName() );
                        $list = SpecialPage::getTitleFor( 'Unblock', $this->target->getName() );
                } else {
                        $message = wfMsgExt( 'ipb-unblock', array( 'parseinline' ) );
                        $list = SpecialPage::getTitleFor( 'Unblock' );
                }
                $links[] = Linker::linkKnown( $list, $message, array() );

                # Link to the block list
                $links[] = Linker::linkKnown(
                        SpecialPage::getTitleFor( 'BlockList' ),
                        wfMsg( 'ipb-blocklist' )
                );

                $user = $this->getUser();

                # Link to edit the block dropdown reasons, if applicable
                if ( $user->isAllowed( 'editinterface' ) ) {
                        $links[] = Linker::link(
                                Title::makeTitle( NS_MEDIAWIKI, 'Ipbreason-dropdown' ),
                                wfMsgHtml( 'ipb-edit-dropdown' ),
                                array(),
                                array( 'action' => 'edit' )
                        );
                }

                $text =  Html::rawElement(
                        'p',
                        array( 'class' => 'mw-ipb-conveniencelinks' ),
                        $this->getLanguage()->pipeList( $links )
                );

                if( $this->target instanceof User ){
                        # Get relevant extracts from the block and suppression logs, if possible
                        $userpage = $this->target->getUserPage();
                        $out = '';

                        LogEventsList::showLogExtract(
                                $out,
                                'block',
                                $userpage,
                                '',
                                array(
                                        'lim' => 10,
                                        'msgKey' => array( 'blocklog-showlog', $userpage->getText() ),
                                        'showIfEmpty' => false
                                )
                        );
                        $text .= $out;

                        # Add suppression block entries if allowed
                        if( $user->isAllowed( 'suppressionlog' ) ) {
                                LogEventsList::showLogExtract(
                                        $out,
                                        'suppress',
                                        $userpage,
                                        '',
                                        array(
                                                'lim' => 10,
                                                'conds' => array( 'log_action' => array( 'block', 'reblock', 'unblock' ) ),
                                                'msgKey' => array( 'blocklog-showsuppresslog', $userpage->getText() ),
                                                'showIfEmpty' => false
                                        )
                                );

                                $text .= $out;
                        }
                }

                return $text;
        }

        /**
         * Determine the target of the block, and the type of target
         * TODO: should be in Block.php?
         * @param $par String subpage parameter passed to setup, or data value from
         *     the HTMLForm
         * @param $request WebRequest optionally try and get data from a request too
         * @return array( User|string|null, Block::TYPE_ constant|null )
         */
        public static function getTargetAndType( $par, WebRequest $request = null ){
                $i = 0;
                $target = null;

                while( true ){
                        switch( $i++ ){
                                case 0:
                                        # The HTMLForm will check wpTarget first and only if it doesn't get
                                        # a value use the default, which will be generated from the options
                                        # below; so this has to have a higher precedence here than $par, or
                                        # we could end up with different values in $this->target and the HTMLForm!
                                        if( $request instanceof WebRequest ){
                                                $target = $request->getText( 'wpTarget', null );
                                        }
                                        break;
                                case 1:
                                        $target = $par;
                                        break;
                                case 2:
                                        if( $request instanceof WebRequest ){
                                                $target = $request->getText( 'ip', null );
                                        }
                                        break;
                                case 3:
                                        # B/C @since 1.18
                                        if( $request instanceof WebRequest ){
                                                $target = $request->getText( 'wpBlockAddress', null );
                                        }
                                        break;
                                case 4:
                                        break 2;
                        }

                        list( $target, $type ) = Block::parseTarget( $target );

                        if( $type !== null ){
                                return array( $target, $type );
                        }
                }

                return array( null, null );
        }

        /**
         * HTMLForm field validation-callback for Target field.
         * @since 1.18
         * @param $value String
         * @param $alldata Array
         * @param $form HTMLForm
         * @return Message
         */
        public static function validateTargetField( $value, $alldata, $form ) {
                global $wgBlockCIDRLimit;

                list( $target, $type ) = self::getTargetAndType( $value );

                if( $type == Block::TYPE_USER ){
                        # TODO: why do we not have a User->exists() method?
                        if( !$target->getId() ){
                                return $form->msg( 'nosuchusershort',
                                        wfEscapeWikiText( $target->getName() ) );
                        }

                        $status = self::checkUnblockSelf( $target, $form->getUser() );
                        if ( $status !== true ) {
                                return $form->msg( 'badaccess', $status );
                        }

                } elseif( $type == Block::TYPE_RANGE ){
                        list( $ip, $range ) = explode( '/', $target, 2 );

                        if( ( IP::isIPv4( $ip ) && $wgBlockCIDRLimit['IPv4'] == 32 )
                                || ( IP::isIPv6( $ip ) && $wgBlockCIDRLimit['IPv6'] == 128 ) )
                        {
                                # Range block effectively disabled
                                return $form->msg( 'range_block_disabled' );
                        }

                        if( ( IP::isIPv4( $ip ) && $range > 32 )
                                || ( IP::isIPv6( $ip ) && $range > 128 ) )
                        {
                                # Dodgy range
                                return $form->msg( 'ip_range_invalid' );
                        }

                        if( IP::isIPv4( $ip ) && $range < $wgBlockCIDRLimit['IPv4'] ) {
                                return $form->msg( 'ip_range_toolarge', $wgBlockCIDRLimit['IPv4'] );
                        }

                        if( IP::isIPv6( $ip ) && $range < $wgBlockCIDRLimit['IPv6'] ) {
                                return $form->msg( 'ip_range_toolarge', $wgBlockCIDRLimit['IPv6'] );
                        }
                } elseif( $type == Block::TYPE_IP ){
                        # All is well
                } else {
                        return $form->msg( 'badipaddress' );
                }

                return true;
        }

        /**
         * Submit callback for an HTMLForm object, will simply pass
         * @param $data array
         * @param $form HTMLForm
         * @return Bool|String
         */
        public static function processUIForm( array $data, HTMLForm $form ) {
                return self::processForm( $data, $form->getContext() );
        }

        /**
         * Given the form data, actually implement a block
         * @param  $data Array
         * @param  $context IContextSource
         * @return Bool|String
         */
        public static function processForm( array $data, IContextSource $context ){
                global $wgBlockAllowsUTEdit;

                $performer = $context->getUser();

                // Handled by field validator callback
                // self::validateTargetField( $data['Target'] );

                # This might have been a hidden field or a checkbox, so interesting data
                # can come from it
                $data['Confirm'] = !in_array( $data['Confirm'], array( '', '0', null, false ), true );

                list( $target, $type ) = self::getTargetAndType( $data['Target'] );
                if( $type == Block::TYPE_USER ){
                        $user = $target;
                        $target = $user->getName();
                        $userId = $user->getId();

                        # Give admins a heads-up before they go and block themselves.  Much messier
                        # to do this for IPs, but it's pretty unlikely they'd ever get the 'block'
                        # permission anyway, although the code does allow for it
                        if( $target === $performer->getName() &&
                                ( $data['PreviousTarget'] !== $data['Target'] || !$data['Confirm'] ) )
                        {
                                return array( 'ipb-blockingself' );
                        }
                } elseif( $type == Block::TYPE_RANGE ){
                        $userId = 0;
                } elseif( $type == Block::TYPE_IP ){
                        $target = $target->getName();
                        $userId = 0;
                } else {
                        # This should have been caught in the form field validation
                        return array( 'badipaddress' );
                }

                if( ( strlen( $data['Expiry'] ) == 0) || ( strlen( $data['Expiry'] ) > 50 )
                        || !self::parseExpiryInput( $data['Expiry'] ) )
                {
                        return array( 'ipb_expiry_invalid' );
                }

                if( !isset( $data['DisableEmail'] ) ){
                        $data['DisableEmail'] = false;
                }

                # If the user has done the form 'properly', they won't even have been given the
                # option to suppress-block unless they have the 'hideuser' permission
                if( !isset( $data['HideUser'] ) ){
                        $data['HideUser'] = false;
                }

                if( $data['HideUser'] ) {
                        if( !$performer->isAllowed('hideuser') ){
                                # this codepath is unreachable except by a malicious user spoofing forms,
                                # or by race conditions (user has oversight and sysop, loads block form,
                                # and is de-oversighted before submission); so need to fail completely
                                # rather than just silently disable hiding
                                return array( 'badaccess-group0' );
                        }

                        # Recheck params here...
                        if( $type != Block::TYPE_USER ) {
                                $data['HideUser'] = false; # IP users should not be hidden
                        } elseif( !in_array( $data['Expiry'], array( 'infinite', 'infinity', 'indefinite' ) ) ) {
                                # Bad expiry.
                                return array( 'ipb_expiry_temp' );
                        } elseif( $user->getEditCount() > self::HIDEUSER_CONTRIBLIMIT ) {
                                # Typically, the user should have a handful of edits.
                                # Disallow hiding users with many edits for performance.
                                return array( 'ipb_hide_invalid' );
                        } elseif( !$data['Confirm'] ){
                                return array( 'ipb-confirmhideuser' );
                        }
                }

                # Create block object.
                $block = new Block();
                $block->setTarget( $target );
                $block->setBlocker( $performer );
                $block->mReason = $data['Reason'][0];
                $block->mExpiry = self::parseExpiryInput( $data['Expiry'] );
                $block->prevents( 'createaccount', $data['CreateAccount'] );
                $block->prevents( 'editownusertalk', ( !$wgBlockAllowsUTEdit || $data['DisableUTEdit'] ) );
                $block->prevents( 'sendemail', $data['DisableEmail'] );
                $block->isHardblock( $data['HardBlock'] );
                $block->isAutoblocking( $data['AutoBlock'] );
                $block->mHideName = $data['HideUser'];

                if( !wfRunHooks( 'BlockIp', array( &$block, &$performer ) ) ) {
                        return array( 'hookaborted' );
                }

                # Try to insert block. Is there a conflicting block?
                $status = $block->insert();
                if( !$status ) {
                        # Show form unless the user is already aware of this...
                        if( !$data['Confirm'] || ( array_key_exists( 'PreviousTarget', $data )
                                && $data['PreviousTarget'] !== $target ) )
                        {
                                return array( array( 'ipb_already_blocked', $block->getTarget() ) );
                        # Otherwise, try to update the block...
                        } else {
                                # This returns direct blocks before autoblocks/rangeblocks, since we should
                                # be sure the user is blocked by now it should work for our purposes
                                $currentBlock = Block::newFromTarget( $target );

                                if( $block->equals( $currentBlock ) ) {
                                        return array( array( 'ipb_already_blocked', $block->getTarget() ) );
                                }

                                # If the name was hidden and the blocking user cannot hide
                                # names, then don't allow any block changes...
                                if( $currentBlock->mHideName && !$performer->isAllowed( 'hideuser' ) ) {
                                        return array( 'cant-see-hidden-user' );
                                }

                                $currentBlock->delete();
                                $status = $block->insert();
                                $logaction = 'reblock';

                                # Unset _deleted fields if requested
                                if( $currentBlock->mHideName && !$data['HideUser'] ) {
                                        RevisionDeleteUser::unsuppressUserName( $target, $userId );
                                }

                                # If hiding/unhiding a name, this should go in the private logs
                                if( (bool)$currentBlock->mHideName ){
                                        $data['HideUser'] = true;
                                }
                        }
                } else {
                        $logaction = 'block';
                }

                wfRunHooks( 'BlockIpComplete', array( $block, $performer ) );

                # Set *_deleted fields if requested
                if( $data['HideUser'] ) {
                        RevisionDeleteUser::suppressUserName( $target, $userId );
                }

                # Can't watch a rangeblock
                if( $type != Block::TYPE_RANGE && $data['Watch'] ) {
                        $performer->addWatch( Title::makeTitle( NS_USER, $target ) );
                }

                # Block constructor sanitizes certain block options on insert
                $data['BlockEmail'] = $block->prevents( 'sendemail' );
                $data['AutoBlock'] = $block->isAutoblocking();

                # Prepare log parameters
                $logParams = array();
                $logParams[] = $data['Expiry'];
                $logParams[] = self::blockLogFlags( $data, $type );

                # Make log entry, if the name is hidden, put it in the oversight log
                $log_type = $data['HideUser'] ? 'suppress' : 'block';
                $log = new LogPage( $log_type );
                $log_id = $log->addEntry(
                        $logaction,
                        Title::makeTitle( NS_USER, $target ),
                        $data['Reason'][0],
                        $logParams
                );
                # Relate log ID to block IDs (bug 25763)
                $blockIds = array_merge( array( $status['id'] ), $status['autoIds']  );
                $log->addRelations( 'ipb_id', $blockIds, $log_id );

                # Report to the user
                return true;
        }

        /**
         * Get an array of suggested block durations from MediaWiki:Ipboptions
         * @todo FIXME: This uses a rather odd syntax for the options, should it be converted
         *     to the standard "**<duration>|<displayname>" format?
         * @param $lang Language|null the language to get the durations in, or null to use
         *     the wiki's content language
         * @return Array
         */
        public static function getSuggestedDurations( $lang = null ){
                $a = array();
                $msg = $lang === null
                        ? wfMessage( 'ipboptions' )->inContentLanguage()->text()
                        : wfMessage( 'ipboptions' )->inLanguage( $lang )->text();

                if( $msg == '-' ){
                        return array();
                }

                foreach( explode( ',', $msg ) as $option ) {
                        if( strpos( $option, ':' ) === false ){
                                $option = "$option:$option";
                        }

                        list( $show, $value ) = explode( ':', $option );
                        $a[htmlspecialchars( $show )] = htmlspecialchars( $value );
                }

                return $a;
        }

        /**
         * Convert a submitted expiry time, which may be relative ("2 weeks", etc) or absolute
         * ("24 May 2034", etc), into an absolute timestamp we can put into the database.
         * @param $expiry String: whatever was typed into the form
         * @return String: timestamp or "infinity" string for the DB implementation
         */
        public static function parseExpiryInput( $expiry ) {
                static $infinity;
                if( $infinity == null ){
                        $infinity = wfGetDB( DB_SLAVE )->getInfinity();
                }

                if ( $expiry == 'infinite' || $expiry == 'indefinite' ) {
                        $expiry = $infinity;
                } else {
                        $expiry = strtotime( $expiry );

                        if ( $expiry < 0 || $expiry === false ) {
                                return false;
                        }

                        $expiry = wfTimestamp( TS_MW, $expiry );
                }

                return $expiry;
        }

        /**
         * Can we do an email block?
         * @param $user User: the sysop wanting to make a block
         * @return Boolean
         */
        public static function canBlockEmail( $user ) {
                global $wgEnableUserEmail, $wgSysopEmailBans;

                return ( $wgEnableUserEmail && $wgSysopEmailBans && $user->isAllowed( 'blockemail' ) );
        }

        /**
         * bug 15810: blocked admins should not be able to block/unblock
         * others, and probably shouldn't be able to unblock themselves
         * either.
         * @param $user User|Int|String
         * @param $performer User user doing the request
         * @return Bool|String true or error message key
         */
        public static function checkUnblockSelf( $user, User $performer ) {
                if ( is_int( $user ) ) {
                        $user = User::newFromId( $user );
                } elseif ( is_string( $user ) ) {
                        $user = User::newFromName( $user );
                }

                if( $performer->isBlocked() ){
                        if( $user instanceof User && $user->getId() == $performer->getId() ) {
                                # User is trying to unblock themselves
                                if ( $performer->isAllowed( 'unblockself' ) ) {
                                        return true;
                                # User blocked themselves and is now trying to reverse it
                                } elseif ( $performer->blockedBy() === $performer->getName() ) {
                                        return true;
                                } else {
                                        return 'ipbnounblockself';
                                }
                        } else {
                                # User is trying to block/unblock someone else
                                return 'ipbblocked';
                        }
                } else {
                        return true;
                }
        }

        /**
         * Return a comma-delimited list of "flags" to be passed to the log
         * reader for this block, to provide more information in the logs
         * @param $data Array from HTMLForm data
         * @param $type Block::TYPE_ constant (USER, RANGE, or IP)
         * @return array
         */
        protected static function blockLogFlags( array $data, $type ) {
                global $wgBlockAllowsUTEdit;
                $flags = array();

                # when blocking a user the option 'anononly' is not available/has no effect -> do not write this into log
                if( !$data['HardBlock'] && $type != Block::TYPE_USER ){
                        // For grepping: message block-log-flags-anononly
                        $flags[] = 'anononly';
                }

                if( $data['CreateAccount'] ){
                        // For grepping: message block-log-flags-nocreate
                        $flags[] = 'nocreate';
                }

                # Same as anononly, this is not displayed when blocking an IP address
                if( !$data['AutoBlock'] && $type == Block::TYPE_USER ){
                        // For grepping: message block-log-flags-noautoblock
                        $flags[] = 'noautoblock';
                }

                if( $data['DisableEmail'] ){
                        // For grepping: message block-log-flags-noemail
                        $flags[] = 'noemail';
                }

                if( $wgBlockAllowsUTEdit && $data['DisableUTEdit'] ){
                        // For grepping: message block-log-flags-nousertalk
                        $flags[] = 'nousertalk';
                }

                if( $data['HideUser'] ){
                        // For grepping: message block-log-flags-hiddenname
                        $flags[] = 'hiddenname';
                }

                return implode( ',', $flags );
        }

        /**
         * Process the form on POST submission.
         * @param  $data Array
         * @return Bool|Array true for success, false for didn't-try, array of errors on failure
         */
        public function onSubmit( array $data ) {
                // This isn't used since we need that HTMLForm that's passed in the
                // second parameter. See alterForm for the real function
        }

        /**
         * Do something exciting on successful processing of the form, most likely to show a
         * confirmation message
         */
        public function onSuccess() {
                $out = $this->getOutput();
                $out->setPageTitle( $this->msg( 'blockipsuccesssub' ) );
                $out->addWikiMsg( 'blockipsuccesstext',  $this->target );
        }
}

# BC @since 1.18
class IPBlockForm extends SpecialBlock {}