I have a simple cmd.php page to run commands I enter using shell_exec () and show the output.
- PHP is running as CGI
- Entering "php -v" and most commands just show "Content-type: text/html" and then the current page's HTML source.
However, calling PHP with an invalid parameter (/usr/bin/php -z) shows PHPs usage:
Usage: php [-q] [-h] [-s] [-v] [-i] [-f ] php [args...]
etc...
I attached a couple of images to show what I mean.
PHP -v doesn't produce expected output
PHP -z shows PHP's usage
Any ideas?
Edit
cmd.php
<?php
if ( isset ( $_POST['submit'] ) ) :
$response = shell_exec ( escapeshellcmd ( stripslashes ( $_POST['cmd'] ) ) );
endif;
?><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html>
<head>
<style type="text/css">
pre#response { border: 1px solid #e0e0e0; padding: .5em; }
</style>
<title>Command</title>
</head>
<body>
<form action="cmd.php" method="post">
<p><input type="text" name="cmd" id="cmd" value="<?php echo @htmlspecialchars ( stripslashes ( $_POST['cmd'] ) ); ?>" size="50" />
<button type="submit" name="submit" id="submit" value="Submit">Submit</button>
</p>
</form>
<?php
if ( isset ( $response ) ) :
?>
<pre开发者_运维问答 id="response"><?php
if ( empty ( $response ) ) :
echo 'No response.';
else :
echo htmlspecialchars ( $response );
endif;
?></pre>
<?php
endif;
?>
</body>
</html>
shell_exec() only returns the characters that have been written to the stdout of the executed process, but not stderr. Try redirecting stderr to stdout so that error messages will be stored in $response.
<?php
define('REDIRECT_STDERR', 1);
if ( isset ( $_POST['submit'] ) ) :
$cmd = escapeshellcmd ( stripslashes ($_POST['cmd']) );
if ( defined('REDIRECT_STDERR') && REDIRECT_STDERR ) :
$cmd .= ' 2>&1';
endif;
$response = shell_exec( $cmd );
endif;
?><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html>
<head>
<style type="text/css">
pre#response { border: 1px solid #e0e0e0; padding: .5em; }
</style>
<title>Command</title>
</head>
<body>
<form action="cmd.php" method="post">
<p>
<input type="text" name="cmd" id="cmd" value="<?php echo @htmlspecialchars ( stripslashes ( $_POST['cmd'] ) ); ?>" size="50" />
<button type="submit" name="submit" id="submit" value="Submit">Submit</button>
</p>
</form>
<?php if ( isset ( $cmd ) ) : ?>
<fieldset><legend><?php echo htmlspecialchars($cmd); ?></legend>
<pre id="response"><?php var_dump($repsonse); ?></pre>
</fieldset>
<?php endif; ?>
</body>
</html>
Please check php.ini used by php from command line. I had same problem (no output from php command line), tried replacing current php.ini with php.ini-production and command line php started to work fine. It appears that some configuration variables were modified in recent php version (upgraded from 5.3.10 to 5.4.3).
精彩评论