除了 wag2369 发布的答案之外，请确保执行以下操作：
安装 pear，它是 PHP 的扩展管理器：
yum install pear
从 yum 安装 pam-devel
yum install pam-devel
安装 PHP PAM 扩展
pecl install --alldeps PAM
--alldeps：表示自动安装所有依赖项
修改文件/etc/php.ini并输入以下内容：
extension=pam.so
pam.servicename="php"
执行以下操作以允许 PAM php 服务：
cd /etc/pam.d
ln -s login /etc/pam.d/php
重启阿帕奇：
/etc/init.d/httpd restart
/etc/shadow 应该是可读的（这是一个安全漏洞，请重新考虑）
chmod g+r,o+r /etc/shadow
如果尚未安装，请安装 expect
yum install expect
修复 wag2369 贴出的代码中的 bug 或者直接复制下面的修改代码： 使用 array_push($error,..) 而不是 array_push(&$error, ...) 'passwd: password updated successfully' 不应该使用，使用“passwd：所有身份验证令牌更新成功。” 改为检查。
<?php
$messages = array();
function change_password ($user, $currpwd, $newpwd) {
// Open a handle to expect in write mode
$p = popen('/usr/bin/expect','w');
// Log conversation for verification
$log = '/tmp/passwd_' . md5($user . time());
$cmd = "";
$cmd .= "log_file -a \"$log\"; ";
// Spawn a shell as $user
$cmd .= "spawn /bin/su $user; ";
$cmd .= "expect \"Password:\"; ";
$cmd .= "send \"$currpwd\\r\"; ";
$cmd .= "expect \"$user@\"; ";
// Change the unix password
$cmd .= "send \"/usr/bin/passwd\\r\"; ";
$cmd .= "expect \"(current) UNIX password:\"; ";
$cmd .= "send \"$currpwd\\r\"; ";
$cmd .= "expect \"Enter new UNIX password:\"; ";
$cmd .= "send \"$newpwd\\r\"; ";
$cmd .= "expect \"Retype new UNIX password:\"; ";
$cmd .= "send \"$newpwd\\r\"; ";
$cmd .= "expect \"passwd: all authentication tokens updated successfully.\"; ";
// Commit the command to expect & close
fwrite($p, $cmd); pclose ($p);
// Read & delete the log
$fp = fopen($log,'r');
$output = fread($fp, 2048);
fclose($fp); unlink($log);
$output = explode("\n",$output);
return (trim($output[count($output)-2]) == 'passwd: all authentication tokens updated successfully.') ? true : false;
}
function process_post() {
if ((!isset($_SERVER['HTTP_REFERER']))
|| (strpos($_SERVER['HTTP_REFERER'], $_SERVER['SCRIPT_NAME']) === FALSE)) {
echo "GO AWAY!";
exit();
return FALSE;
}
global $messages;
$username = trim($_POST['username']);
$password_current = trim($_POST['password_current']);
$password_new = trim($_POST['password_new']);
$password_confirm = trim($_POST['password_confirm']);
// Check for blanks
if ($username == '' || $password_current == '' || $password_new == '' || $password_confirm == '') {
array_push($messages, "ERROR: You cannot leave any field empty.");
return FALSE;
}
// Check username
if (!ctype_alnum($username)) {
array_push($messages, "ERROR: You've entered an invalid username.");
return FALSE;
}
// Check to see if new password is correctly typed
if ($password_new != $password_confirm) {
array_push($messages, "ERROR: New Password and Confirmation do not match.");
return FALSE;
}
// Check if current password is valid (not really neccessary)
$error = '';
if (!pam_auth($username, $password_current, $error, FALSE)) {
if (trim($error) == "Permission denied (in pam_authenticate)")
array_push($messages, "ERROR: Your username/password was not accepted.");
else
array_push($messages, "ERROR: " . $error);
return FALSE;
}
if (change_password ($username, $password_current, $password_new))
array_push($messages, "Password Successfully Changed");
else
array_push($messages, "ERROR: Password change failed.");
}
if ($_SERVER['REQUEST_METHOD'] == 'POST') process_post();
?><html>
<head>
<title>Passwords</title>
<style type="text/css">
body {
font-family: Verdana, Arial, sans-serif;
font-size: 12px;
}
label {
width: 150px;
display: block;
float: left;
}
input {
float: left;
}
br {
clear: both;
}
.message {
font-size: 11px;
font-weight: bold;
}
.error {
color:#C00;
}
</style>
</head>
<body>
<h2>Change Passwords</h2>
<form action="<?= $_SERVER['SCRIPT_NAME'] ?>" method="post">
<fieldset>
<? if (count($messages) != 0) {
foreach ($messages as $message) { ?>
<p class="message<?= ((strpos($message, 'ERROR:') === FALSE) ? '' : ' error') ?>"><?= $message ?></p>
<? } } ?>
<label>Username: </label>
<input type="text" name="username" value="halaluya" /><br />
<label>Current Password:</label>
<input type="password" name="password_current" value="dev0te@m" /><br />
<label>New Password:</label>
<input type="password" name="password_new" value="123" /><br />
<label>Confirm Password:</label>
<input type="password" name="password_confirm" value="123" /><br />
<input type="reset" value="Reset" /> <input type="submit" value="Submit" />
</fieldset>
</form>
</body>
</html>