一个完整php验证码实例程序

时间：2015-01-23 来源：西部数据作者：西部数据

<!doctype html public "-//w3c//dtd xhtml 1.0 transitional//en" "http://www.phpfensi.com/tr/xhtml1/dtd/xhtml1-transitional.dtd">

<html lang="en-us" xml:lang="en-us" xmlns="http://www.w3.org/1999/xhtml">

<title>login</title>

<link rel="stylesheet" type="text/css" href="/tryit.css" />

<script type="text/javascript">

function getpinimg()

{

document.getelementbyid("pinimg").src="log_demo.php?a=pin&r=" + math.random();

}

</script>

</head>

<body>

<form action="log_demo.php" method="get">

<input type="hidden" name="a" value="log" />

user:<input type="text" name="user" size="20" value="test" /><br /><br />

password:<input type="password" name="pass" size="12" value="123456" /><br /><br />

pincode:<input type="text" name="pin" size="8" value="" />

<input type="button" value="getpin" onclick="getpinimg();">

<img id="pinimg" src="log_demo.php?a=pin" onclick="getpinimg();" />

<input type="submit" value="submit"><br />

</form>

</body>

</html>

log_demo.php代码如下:

<?php

require_once("log_aux.php");

if ($_get['a'] == "pin") {

getpinimg();

exit;

}

if ($_get['a'] == "log") {

$ret = checkpincookie($_get['pin'], 300);

if ($ret < 0) {//开源代码phpfensi.com

  echo "pin error:$ret ";

  exit;

}

// check user name and password.

echo "ok..$ret ";

if ("123xx" == 123) {

  echo "dddd ";

}

echo $_get['u'];

}

log_aux.php代码如下:

<?php

$magic_a = "www.phpfensi.com34589";

$magic_b = "234566***+";

function getpincookie($pin_code)

{

global $magic_a;

global $magic_b;

$now = time();

$client_ip = $_server['remote_addr'];

$pin = md5($now . $client_ip . $magic_a . $pin_code . $maigc_b) . $now;

return $pin;

}

function checkpincookie($pin_code_in, $timeout=300) // 5 miniuteswww.phpfensi.com

{

global $magic_a;

global $magic_b;

$pin = substr($_cookie['pin'], 0, 32);

$time = substr($_cookie['pin'], 32);

$now = time();

if ($now - $time > $timeout) {

  return -100;  // time_out

}

$pin_code_in = strtolower($pin_code_in);

$client_ip = $_server['remote_addr'];

$pin_2 = md5($time . $client_ip . $magic_a . $pin_code_in . $maigc_b);

if ($pin === $pin_2) {

  return 0;

} else {

  return -200; // pincode is error.

}

}

function getpinimg()

{

// $rnd = rand(0, 10);

$rnd = 0;

$path = "./www.phpfensi.com/" . substr("00000$rnd", -4);

for ($i = 0; $i < 4; ++$i) {

  if (__getpinimg($path)) {

   break;

  }

}

exit;

}

function __getpinimg($path)

{

require("$path/pinmap.php");

$pinv = $pin[rand(0, $pin_max)];

list ($file, $pin_code) = explode('#', $pinv);

$filepath = "$path/$file$pin_ext";

//  output pincode image.

$fh = fopen($filepath, "rb");

if (!$fh) {

  return false;

}

$data = fread($fh, 10240); // php just read max size: 8k.

fclose($fh);

if (strlen($data) < 200) {

  return false;

}

// set cookie;

header("content-type: image/jpeg");

$pin_code = strtolower($pin_code);

$pin = getpincookie($pin_code);

setcookie("pin", $pin);

echo $data;

return true;

}