php 한글 메뉴얼 도움말 검색 사이트 Escape shell metacharacters [function.escapeshellcmd]

설명

string escapeshellcmd ( string $command )

escapeshellcmd() escapes any characters in a string that might be used to trick a shell command into executing arbitrary commands. This function should be used to make sure that any data coming from user input is escaped before this data is passed to the exec() or system() functions, or to the backtick operator.

Following characters are preceded by a backslash: #&;`|*?~<>^()[]{}$\, \x0A and \xFF. ' and " are escaped only if they are not paired. In Windows, all these characters plus % are replaced by a space instead.

인수

command: The command that will be escaped.

반환값

The escaped string.

예제

Example #1 escapeshellcmd() example


<?php
// We allow arbitrary number of arguments intentionally here.
$command = './configure '.$_POST['configure_options'];

$escaped_command = escapeshellcmd($command);
 
system($escaped_command);
?>

Warning

escapeshellcmd() should be used on the whole command string, and it still allows the attacker to pass arbitrary number of arguments. For escaping a single argument escapeshellarg() should be used instead.

참고

escapeshellarg() - Escape a string to be used as a shell argument
exec() - Execute an external program
popen() - Opens process file pointer
system() - Execute an external program and display the output
backtick operator