Network Funzioni

Indice dei contenuti

  • checkdnsrr — Controlla i record DNS relativi ad un host Internet o indirizzo IP
  • closelog — Chiude la connessione al logger di sistema
  • define_syslog_variables — Inizializza tutte le costanti collegate al syslog
  • dns_check_record — Alias di checkdnsrr
  • dns_get_mx — Alias di getmxrr
  • dns_get_record — Fetch DNS Resource Records associated with a hostname
  • fsockopen — Apre una connessione a un socket appartenente a un dominio Internet o Unix
  • gethostbyaddr — Ottiene l'host Internet corrispondente a un dato indirizzo IP
  • gethostbyname — Ottiene l'indirizzo IP corrispondente a un dato hostname Internet
  • gethostbynamel — Ottiene la lista degli indirizzi IP corrispondenti a un dato hostname Internet
  • gethostname — Gets the host name
  • getmxrr — Ottiene i record MX corrispondenti a un dato nome di host Internet
  • getprotobyname — Ottiene il numero del protocollo associato al nome del protocollo
  • getprotobynumber — Ottiene il nome del protocollo associato al numero del protocollo
  • getservbyname — Ottiene il numero di porta associato ad un servizio Internet e ad un protocollo
  • getservbyport — Ottiene il servizio Internet corrispondente ad una porta e ad un protocollo
  • header_register_callback — Call a header function
  • header_remove — Remove previously set headers
  • header — Send a raw HTTP header
  • headers_list — Returns a list of response headers sent (or ready to send)
  • headers_sent — Checks if or where headers have been sent
  • http_response_code — Get or Set the HTTP response code
  • inet_ntop — Converts a packed internet address to a human readable representation
  • inet_pton — Converts a human readable IP address to its packed in_addr representation
  • ip2long — Converts a string containing an (IPv4) Internet Protocol dotted address into a proper address. Converte una stringa contenente un indirizzo di rete del Protocollo Internet (IPv4) in un indirizzo espresso come tipo di dato int.
  • long2ip — Converte un indirizzo di rete del Protocollo Internet (IPv4) in una stringa contenente un indirizzo espresso secondo la notazione standard di Internet.
  • openlog — Apre una connessione al logger di sistema
  • pfsockopen — Apre una connessione persistente Internet o di tipo domain socket Unix
  • setcookie — Send a cookie
  • setrawcookie — Send a cookie without urlencoding the cookie value
  • socket_get_status — Alias di stream_get_meta_data
  • socket_set_blocking — Alias di stream_set_blocking
  • socket_set_timeout — Alias di stream_set_timeout
  • syslog — Genera un messaggio del system log
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User Contributed Notes 11 notes

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5
claudiu at cnixs dot com
7 years ago
A simple and very fast function to check against CIDR.

Your previous examples are too complicated and involves a lot of functions call.

Here it is (only with arithmetic operators and call only to ip2long () and split() ):
<?php
 
function ipCIDRCheck ($IP, $CIDR) {
    list (
$net, $mask) = split ("/", $CIDR);
   
   
$ip_net = ip2long ($net);
   
$ip_mask = ~((1 << (32 - $mask)) - 1);

   
$ip_ip = ip2long ($IP);

   
$ip_ip_net = $ip_ip & $ip_mask;

    return (
$ip_ip_net == $ip_net);
  }
?>
call example: <?php echo ipCheck ("192.168.1.23", "192.168.1.0/24"); ?>
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2
David GASTALDIN
7 years ago
Here a IP-Range to CIDRs function that I wrote for the purpose of filling my Postfix client.cidr with ripe-ncc data to block spamming from useless countries. Strcmp functions are meant to work around the silly PHP string comparison which inevitably tries compare strings as numbers when possible. I'll make no comment about that fact ... bit I have to bite my tong hard :

function PlageVersCIDRs($ip_min, $ip_max) {
    $cidrs = array();
    $ip_min_bin = sprintf('%032b', $ip_min);
    $ip_max_bin = sprintf('%032b', $ip_max);
    $ip_cour_bin = $ip_min_bin;
    while (strcmp($ip_cour_bin, $ip_max_bin) <= 0) {
        $lng_reseau = 32;
        $ip_reseau_bin = $ip_cour_bin;
        while (($ip_cour_bin[$lng_reseau - 1] == '0') && (strcmp(substr_replace($ip_reseau_bin, '1', $lng_reseau - 1, 1), $ip_max_bin) <= 0)) {
            $ip_reseau_bin[$lng_reseau - 1] = '1';
            $lng_reseau--;
        }
        $cidrs[] = long2ip(bindec($ip_cour_bin)).'/'.$lng_reseau;
        $ip_cour_bin = sprintf('%032b', bindec($ip_reseau_bin) + 1);
    }
    return $cidrs;
}
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2
nexxer at rogers dot com
9 years ago
In Trevor Hemsley's translation of the perl range2cidr function, the

while ($end > $start)

condition should be

while ($end >= $start)

otherwise it won't work for /32s, ie if you feed range2cidr("1.2.3.4", "1.2.3.4").

-- nex
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-1
samuele at norsam dot org
11 years ago
To find if an IP is in a net/mask (very fast):
<?php
function isIPIn($ip,$net,$mask) {
  
$lnet=ip2long($net);
  
$lip=ip2long($ip);
  
$binnet=str_pad( decbin($lnet),32,"0","STR_PAD_LEFT" );
  
$firstpart=substr($binnet,0,$mask);
  
$binip=str_pad( decbin($lip),32,"0","STR_PAD_LEFT" );
  
$firstip=substr($binip,0,$mask);
   return(
strcmp($firstpart,$firstip)==0);
   }
?>

This function can be compacted, avoiding some variable settings, but the function will not be too clear to read...
Example code, used to made a kind of location service network-based:

<?php
$n
= array ( "192.168.0.0/16"   => "TUSCANY",
            
"192.168.1.0/24"   => "- Florence",
            
"192.168.2.0/24"   => "- Pisa",
            
"192.168.3.0/24"   => "- Siena",
            
"192.168.64.0/21" => "- Tuscan Archipelago",
            
"192.168.64.0/23" => "--- Elba Island",
            
"192.168.66.0/24" => "--- Capraia Island",
            
"192.168.67.0/24" => "--- Giannutri Island");

// Normally you should use the following line
$myip = $HTTP_SERVER_VARS['REMOTE_ADDR'];
// This is first example: returns Tuscany/Pisa
$myip = "192.168.2.33";
// This is second example: returns Tuscany/T.Arch./Elba
$myip = "192.168.65.34";

echo
"Your position:<br />\n";
foreach (
$n as $k=>$v ) {
   list(
$net,$mask)=split("/",$k);
   if (
isIPIn($myip,$net,$mask)) {
       echo
$n[$k]."<br />\n"; }
   }
?>

and so on...
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-1
anderson at piq dot com dot br
11 years ago
If you want to get the interface of an IP, based on the local route table, use this.

function GetIfaceforIP($user_ip)
{
    $route = "/bin/netstat -rn";

    exec($route, $aoutput);
    foreach($aoutput as $key => $line)
    {
        if($key > 1)
        {
            $line = ereg_replace("[[:space:]]+",",",$line);
            list($network, $gateway, $mask, $flags, $mss, $window, $irtt, $iface) = explode(",", $line)
            if((ip2long($user_ip) & ip2long($mask)) == ip2long($network))
            {
                return $iface;
            }
        }
    }
}
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-1
Anonymous
11 years ago
Alternative cidr_conv function - a little easier to follow

function cidr_conv($cidr_address) {
  $first = substr($cidr_address, 0, strpos($cidr_address, "/"));
  $netmask = substr(strstr($cidr_address, "/"), 1);

  $first_bin = str_pad(decbin(ip2long($first)), 32, "0", STR_PAD_LEFT);
  $netmask_bin = str_pad(str_repeat("1", (integer)$netmask), 32, "0", STR_PAD_RIGHT);
 
  for ($i = 0; $i < 32; $i++) {
    if ($netmask_bin[$i] == "1")
      $last_bin .= $first_bin[$i];
    else
      $last_bin .= "1";
  }

  $last = long2ip(bindec($last_bin));

  return "$first - $last";
}
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-1
trevor-hemsley at nospam dot dial dot pipex dot com
12 years ago
Previous example of IP range to CIDR list does not cope with ranges as well as the perl Net::Netmask range2cidrlist() function. In PHP this looks like

<?
function imask($this)
{
// use base_convert not dechex because dechex is broken and returns 0x80000000 instead of 0xffffffff
return base_convert((pow(2,32) - pow(2, (32-$this)))), 10, 16);
}

function imaxblock($ibase, $tbit)
{
while ($tbit > 0)
{
$im = hexdec(imask($tbit-1));
$imand = $ibase & $im;
if ($imand != $ibase)
{
break;
}
$tbit--;
}
return $tbit;
}

function range2cidrlist($istart, $iend)
{
// this function returns an array of cidr lists that map the range given
$s = explode(".", $istart);
// PHP ip2long does not handle leading zeros on IP addresses! 172.016 comes back as 172.14, seems to be treated as octal!
$start = "";
$dot = "";
while (list($key,$val) = each($s))
{
$start = sprintf("%s%s%d",$start,$dot,$val);
$dot = ".";
}
$end = "";
$dot = "";
$e = explode(".",$iend);
while (list($key,$val) = each($e))
{
$end = sprintf("%s%s%d",$end,$dot,$val);
$dot = ".";
}
$start = ip2long($start);
$end = ip2long($end);
$result = array();
while ($end > $start)
{
$maxsize = imaxblock($start,32);
$x = log($end - $start + 1)/log(2);
$maxdiff = floor(32 - floor($x));
$ip = long2ip($start);
if ($maxsize < $maxdiff)
{
$maxsize = $maxdiff;
}
array_push($result,"$ip/$maxsize");
$start += pow(2, (32-$maxsize));
}
return $result;
}
?>
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-1
philippe-at-cyberabuse.org
12 years ago
... and this one will do the opposite (o return NULL for invalid netblocks) :

1.0.0.0 1.0.255.255 -> 1.0.0.0/16
1.0.0.0 1.3.255.255 -> 1.0.0.0/14
192.168.0.0 192.168.0.255 -> 192.168.0.0/24

function ip2cidr($ip_start,$ip_end) {
if(long2ip(ip2long($ip_start))!=$ip_start or long2ip(ip2long($ip_end))!=$ip_end) return NULL;
$ipl_start=(int)ip2long($ip_start);
$ipl_end=(int)ip2long($ip_end);
if($ipl_start>0 && $ipl_end<0) $delta=($ipl_end+4294967296)-$ipl_start;
else $delta=$ipl_end-$ipl_start;
$netmask=str_pad(decbin($delta),32,"0","STR_PAD_LEFT");
if(ip2long($ip_start)==0 && substr_count($netmask,"1")==32) return "0.0.0.0/0";
if($delta<0 or ($delta>0 && $delta%2==0)) return NULL;
for($mask=0;$mask<32;$mask++) if($netmask[$mask]==1) break;
if(substr_count($netmask,"0")!=$mask) return NULL;
return "$ip_start/$mask";
}
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-1
philippe-at-cyberabuse.org
12 years ago
PHP miss CIDR functions.

This one will convert a CIDR like this:
0.0.0.0/16 -> 0.0.0.0 - 0.0.255.255
127.0/16 -> 127.0.0.0 - 127.0.255.255
etc...

function cidrconv($net) {
$start=strtok($net,"/");
$n=3-substr_count($net, ".");
if ($n>0) { for ($i=$n;$i>0;$i--) $start.=".0"; }
$bits1=str_pad(decbin(ip2long($start)),32,"0","STR_PAD_LEFT");
$net=pow(2,(32-substr(strstr($net,"/"),1)))-1;
$bits2=str_pad(decbin($net),32,"0","STR_PAD_LEFT");
for ($i=0;$i<32;$i++) {
if ($bits1[$i]==$bits2[$i]) $final.=$bits1[$i];
if ($bits1[$i]==1 and $bits2[$i]==0) $final.=$bits1[$i];
if ($bits1[$i]==0 and $bits2[$i]==1) $final.=$bits2[$i];
}
return $start." - ".long2ip(bindec($final));
}
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-3
dand at ddchosting.com
8 years ago
When I was working on a project I ran into this problem with redirecting. My solution is as follows:
header("Refresh: 5; url=../main/main.php?".session_id()."");

This allowed me to pass the session_id() which is used throughout site to make sure user has loged in.
I hope this helps!
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-3
metator at netcabo dot pt
9 years ago
Regarding samuele's note:

You can get faster code if you apply directly what happens in  network devices, such as routers. If you AND (logic operation) the remote ip against the local netmask the result will be the network ip if the remote ip is from the local network. Example:

    192.168.0.16 = 11000000.10101000.00000000.00010000
& 255.255.255.0 = 11111111.11111111.11111111.00000000
--------------------------------------------------------------
   192.168.0.0 = 11000000.10101000.00000000.00000000

And now the code. My example uses a html form where you place the values you want to test:

<HTML><HEAD><TITLE>Check IP</TITLE>
</HEAD><BODY>
    <form action="<?php echo $_SERVER['PHP_SELF']; ?>" method="POST">

Hope you find this useful.
        IP to check: <input type="text" name="ip"> <br>
        Local network ip: <input type="text" name="net"> <br>
        Local netmask: <input type="text" name="mask"> <br>
        <input type="submit" name="check" value="Check it!">
    </form>
    <?php

/**
* @param string $ip IP to check in dotted decimal format
* @param string $net Network IP in dotted decimal format
* @param string $mask Netmask in dotted decimal format
* @returns true if the ip belongs to the network, false otherwise
**/
function isIPIn($ip, $net, $mask) {
   
//doesn't check for the return value of ip2long
   
$ip = ip2long($_POST['ip']);
   
$rede = ip2long($_POST['net']);
   
$mask = ip2long($_POST['mask']);
   
   
//AND
   
$res = $ip & $mask;
   
    return (
$res == $rede);
}

if (isset(
$_POST['check'])) {
     echo
isIPIn($_POST['ip'], $_POST['net'], $_POST['mask']) ? "IP IN.": "IP OUT.";
}
?>
</BODY><HTML>
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