php中禁止单个ip与ip段访问的代码小结

1.禁止单个IP

<?php
//IP访问限制
if(getenv('HTTP_CLIENT_IP') && strcasecmp(getenv('HTTP_CLIENT_IP'), 'unknown')) {
$userip = getenv('HTTP_CLIENT_IP');
} elseif(getenv('HTTP_X_FORWARDED_FOR') && strcasecmp(getenv('HTTP_X_FORWARDED_FOR'), 'unknown')) {
$userip = getenv('HTTP_X_FORWARDED_FOR');
} elseif(getenv('REMOTE_ADDR') && strcasecmp(getenv('REMOTE_ADDR'), 'unknown')) {
$userip = getenv('REMOTE_ADDR');
} elseif(isset($_SERVER['REMOTE_ADDR']) && $_SERVER['REMOTE_ADDR'] && strcasecmp($_SERVER['REMOTE_ADDR'], 'unknown')) {
$userip = $_SERVER['REMOTE_ADDR'];
}
$banned_ip = array (
"127.0.0.1",
"203.0.0.1",
"56.12.50.65",
"192.168.1.88"
);
if (in_array($userip,$banned_ip)) {
die ("Your IP is block to connect !");
}
echo "小鱼阁测试";
?> 

2.禁止IP段

<?php 
//判断IP访问限制 
if(getenv('HTTP_CLIENT_IP') && strcasecmp(getenv('HTTP_CLIENT_IP'), 'unknown')) { 
$userip = getenv('HTTP_CLIENT_IP'); 
} elseif(getenv('HTTP_X_FORWARDED_FOR') && strcasecmp(getenv('HTTP_X_FORWARDED_FOR'), 'unknown')) { 
$userip = getenv('HTTP_X_FORWARDED_FOR'); 
} elseif(getenv('REMOTE_ADDR') && strcasecmp(getenv('REMOTE_ADDR'), 'unknown')) { 
$userip = getenv('REMOTE_ADDR'); 
} elseif(isset($_SERVER['REMOTE_ADDR']) && $_SERVER['REMOTE_ADDR'] && strcasecmp($_SERVER['REMOTE_ADDR'], 'unknown')) { 
$userip = $_SERVER['REMOTE_ADDR']; 
} 
$ban_range_low=ip2long("217.0.0.0"); //ip段首 
$ban_range_up=ip2long("217.255.255.255");//ip段尾 
$ip=ip2long($userip]); 
if ($ip>$ban_range_low && $ip<$ban_range_up) 
{ 
print "Banned"; 
exit(); 
} 
?> 

另外请注意，PHP的ip2long有bug，请慎用

<?php 
echo ip2long('58.99.11.1'),"<br/>";   //输出是 979569409 
echo ip2long('58.99.011.1'),"<br/>";  //输出是 979568897 
echo ip2long('058.99.11.1'),"<br/>";  //输出是空 
?> 

在PHP 4.x，PHP 5.x中，有前导零的ip转换的结果都不正确。

解决办法，使用自己的函数：

function myip2long($ip){ 
   $ip_arr = split('.',$ip); 
   $iplong = (16777216 * intval($ip_arr[0])) + (65536 * intval($ip_arr[1])) + (256 * intval($ip_arr[2])) + intval($ip_arr[3]); 
   return $iplong; 
}

完毕！