PHP 8.4.0 RC2 available for testing

Network Functions

Table of Contents

  • checkdnsrr — Check DNS records corresponding to a given Internet host name or IP address
  • closelog — Close connection to system logger
  • dns_check_record — Alias of checkdnsrr
  • dns_get_mx — Alias of getmxrr
  • dns_get_record — Fetch DNS Resource Records associated with a hostname
  • fsockopen — Open Internet or Unix domain socket connection
  • gethostbyaddr — Get the Internet host name corresponding to a given IP address
  • gethostbyname — Get the IPv4 address corresponding to a given Internet host name
  • gethostbynamel — Get a list of IPv4 addresses corresponding to a given Internet host name
  • gethostname — Gets the host name
  • getmxrr — Get MX records corresponding to a given Internet host name
  • getprotobyname — Get protocol number associated with protocol name
  • getprotobynumber — Get protocol name associated with protocol number
  • getservbyname — Get port number associated with an Internet service and protocol
  • getservbyport — Get Internet service which corresponds to port and protocol
  • header — Send a raw HTTP header
  • header_register_callback — Call a header function
  • header_remove — Remove previously set headers
  • 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 long integer
  • long2ip — Converts a long integer address into a string in (IPv4) Internet standard dotted format
  • net_get_interfaces — Get network interfaces
  • openlog — Open connection to system logger
  • pfsockopen — Open persistent Internet or Unix domain socket connection
  • setcookie — Send a cookie
  • setrawcookie — Send a cookie without urlencoding the cookie value
  • socket_get_status — Alias of stream_get_meta_data
  • socket_set_blocking — Alias of stream_set_blocking
  • socket_set_timeout — Alias of stream_set_timeout
  • syslog — Generate a system log message
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User Contributed Notes 10 notes

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36
claudiu at cnixs dot com
17 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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11
Anton Avramov - lukav at lukav dot com
7 years ago
An improved version of claudiu at cnixs dot com not using split and working with the following:
ip: 192.168.101.123, CIRD: 192.168.101.144/24

<?php
function ipCIDRCheck ($IP, $CIDR) {
list (
$net, $mask) = explode ('/', $CIDR);

$ip_net = ip2long ($net);
$ip_mask = ~((1 << (32 - $mask)) - 1);

$ip_ip = ip2long ($IP);

return ((
$ip_ip & $ip_mask) == ($ip_net & $ip_mask));
}
?>
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5
Anonymous
8 years ago
improved version of philippe-at-cyberabuse.org's answer:

<?php
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);
$net = (1 << (32 - substr(strstr($net, "/"), 1))) - 1;
$bits2 = str_pad(decbin($net), 32, "0", STR_PAD_LEFT);
$final = "";
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 array(
$start, long2ip(bindec($final)));
}
?>
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2
David GASTALDIN
17 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
philippe-at-cyberabuse.org
22 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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-1
nexxer at rogers dot com
19 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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-2
-dR
8 years ago
This little function might come in handy

<?php
function cidr_range( $cidr, $chkip=null )
{
// Assign IP / mask
list($ip,$mask) = explode("/",$cidr);

// Sanitize IP
$ip1 = preg_replace( '_(\d+\.\d+\.\d+\.\d+).*$_', '$1', "$ip.0.0.0" );

// Calculate range
$ip2 = long2ip( ip2long( $ip1 ) - 1 + ( 1 << ( 32 - $mask) ) );

// are we cidr range cheking?
if ( $chkip != null && ! filter_var( $chkip, FILTER_VALIDATE_IP, FILTER_FLAG_IPV4) === false )
{
return
ip2long( $ip1 ) <= ip2long( $chkip ) && ip2long( $ip2 ) >= ip2long( $chkip ) ? true : false;
} else {
return
"$ip1 - $ip2";
}
}

var_dump( cidr_range( "127.0/16", "127.0.0.1" ) ); // bool(true)
var_dump( cidr_range( "127.0/16", "192.168.0.1" ) ); // bool(false)
var_dump( cidr_range( "192.168.0.0/24" ) ); // string(27) "192.168.0.0 - 192.168.0.255"

?>
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-2
Anonymous
21 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 - $last";
}
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-4
samuele at norsam dot org
20 years ago
To find if an IP is in a net/mask (very fast):
<?php
function isIPIn($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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-5
dand at ddchosting.com
18 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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