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Diffstat (limited to 'www/wiki/includes/shell/Shell.php')
| -rw-r--r-- | www/wiki/includes/shell/Shell.php | 251 |
1 files changed, 251 insertions, 0 deletions
diff --git a/www/wiki/includes/shell/Shell.php b/www/wiki/includes/shell/Shell.php new file mode 100644 index 00000000..742e1424 --- /dev/null +++ b/www/wiki/includes/shell/Shell.php @@ -0,0 +1,251 @@ +<?php +/** + * Class used for executing shell commands + * + * 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 + */ + +namespace MediaWiki\Shell; + +use Hooks; +use MediaWiki\MediaWikiServices; + +/** + * Executes shell commands + * + * @since 1.30 + * + * Use call chaining with this class for expressiveness: + * $result = Shell::command( 'some command' ) + * ->input( 'foo' ) + * ->environment( [ 'ENVIRONMENT_VARIABLE' => 'VALUE' ] ) + * ->limits( [ 'time' => 300 ] ) + * ->execute(); + * + * ... = $result->getExitCode(); + * ... = $result->getStdout(); + * ... = $result->getStderr(); + */ +class Shell { + + /** + * Apply a default set of restrictions for improved + * security out of the box. + * + * Equal to NO_ROOT | SECCOMP | PRIVATE_DEV | NO_LOCALSETTINGS + * + * @note This value will change over time to provide increased security + * by default, and is not guaranteed to be backwards-compatible. + * @since 1.31 + */ + const RESTRICT_DEFAULT = 39; + + /** + * Disallow any root access. Any setuid binaries + * will be run without elevated access. + * + * @since 1.31 + */ + const NO_ROOT = 1; + + /** + * Use seccomp to block dangerous syscalls + * @see <https://en.wikipedia.org/wiki/seccomp> + * + * @since 1.31 + */ + const SECCOMP = 2; + + /** + * Create a private /dev + * + * @since 1.31 + */ + const PRIVATE_DEV = 4; + + /** + * Restrict the request to have no + * network access + * + * @since 1.31 + */ + const NO_NETWORK = 8; + + /** + * Deny execve syscall with seccomp + * @see <https://en.wikipedia.org/wiki/exec_(system_call)> + * + * @since 1.31 + */ + const NO_EXECVE = 16; + + /** + * Deny access to LocalSettings.php (MW_CONFIG_FILE) + * + * @since 1.31 + */ + const NO_LOCALSETTINGS = 32; + + /** + * Don't apply any restrictions + * + * @since 1.31 + */ + const RESTRICT_NONE = 0; + + /** + * Returns a new instance of Command class + * + * @param string|string[] $command String or array of strings representing the command to + * be executed, each value will be escaped. + * Example: [ 'convert', '-font', 'font name' ] would produce "'convert' '-font' 'font name'" + * @return Command + */ + public static function command( $command ) { + $args = func_get_args(); + if ( count( $args ) === 1 && is_array( reset( $args ) ) ) { + // If only one argument has been passed, and that argument is an array, + // treat it as a list of arguments + $args = reset( $args ); + } + $command = MediaWikiServices::getInstance() + ->getShellCommandFactory() + ->create(); + + return $command->params( $args ); + } + + /** + * Check if this class is effectively disabled via php.ini config + * + * @return bool + */ + public static function isDisabled() { + static $disabled = null; + + if ( is_null( $disabled ) ) { + if ( !function_exists( 'proc_open' ) ) { + wfDebug( "proc_open() is disabled\n" ); + $disabled = true; + } else { + $disabled = false; + } + } + + return $disabled; + } + + /** + * Version of escapeshellarg() that works better on Windows. + * + * Originally, this fixed the incorrect use of single quotes on Windows + * (https://bugs.php.net/bug.php?id=26285) and the locale problems on Linux in + * PHP 5.2.6+ (bug backported to earlier distro releases of PHP). + * + * @param string $args,... strings to escape and glue together, or a single array of + * strings parameter. Null values are ignored. + * @return string + */ + public static function escape( /* ... */ ) { + $args = func_get_args(); + if ( count( $args ) === 1 && is_array( reset( $args ) ) ) { + // If only one argument has been passed, and that argument is an array, + // treat it as a list of arguments + $args = reset( $args ); + } + + $first = true; + $retVal = ''; + foreach ( $args as $arg ) { + if ( $arg === null ) { + continue; + } + if ( !$first ) { + $retVal .= ' '; + } else { + $first = false; + } + + if ( wfIsWindows() ) { + // Escaping for an MSVC-style command line parser and CMD.EXE + // Refs: + // * https://web.archive.org/web/20020708081031/http://mailman.lyra.org/pipermail/scite-interest/2002-March/000436.html + // * https://technet.microsoft.com/en-us/library/cc723564.aspx + // * T15518 + // * CR r63214 + // Double the backslashes before any double quotes. Escape the double quotes. + $tokens = preg_split( '/(\\\\*")/', $arg, -1, PREG_SPLIT_DELIM_CAPTURE ); + $arg = ''; + $iteration = 0; + foreach ( $tokens as $token ) { + if ( $iteration % 2 == 1 ) { + // Delimiter, a double quote preceded by zero or more slashes + $arg .= str_replace( '\\', '\\\\', substr( $token, 0, -1 ) ) . '\\"'; + } elseif ( $iteration % 4 == 2 ) { + // ^ in $token will be outside quotes, need to be escaped + $arg .= str_replace( '^', '^^', $token ); + } else { // $iteration % 4 == 0 + // ^ in $token will appear inside double quotes, so leave as is + $arg .= $token; + } + $iteration++; + } + // Double the backslashes before the end of the string, because + // we will soon add a quote + $m = []; + if ( preg_match( '/^(.*?)(\\\\+)$/', $arg, $m ) ) { + $arg = $m[1] . str_replace( '\\', '\\\\', $m[2] ); + } + + // Add surrounding quotes + $retVal .= '"' . $arg . '"'; + } else { + $retVal .= escapeshellarg( $arg ); + } + } + return $retVal; + } + + /** + * Generate a Command object to run a MediaWiki CLI script. + * Note that $parameters should be a flat array and an option with an argument + * should consist of two consecutive items in the array (do not use "--option value"). + * + * @param string $script MediaWiki CLI script with full path + * @param string[] $parameters Arguments and options to the script + * @param array $options Associative array of options: + * 'php': The path to the php executable + * 'wrapper': Path to a PHP wrapper to handle the maintenance script + * @return Command + */ + public static function makeScriptCommand( $script, $parameters, $options = [] ) { + global $wgPhpCli; + // Give site config file a chance to run the script in a wrapper. + // The caller may likely want to call wfBasename() on $script. + Hooks::run( 'wfShellWikiCmd', [ &$script, &$parameters, &$options ] ); + $cmd = isset( $options['php'] ) ? [ $options['php'] ] : [ $wgPhpCli ]; + if ( isset( $options['wrapper'] ) ) { + $cmd[] = $options['wrapper']; + } + $cmd[] = $script; + + return self::command( $cmd ) + ->params( $parameters ) + ->restrict( self::RESTRICT_DEFAULT & ~self::NO_LOCALSETTINGS ); + } +} |