I've been trying to implement a captcha system on my server for a couple days now with no success. I found a simple captcha script, but it is giving me some errors. Here are the errors:
Notice: Undefined index: captchaimg in /var/www/vhosts/wilserv.net/httpdocs/test/captcha.php on line 23
Notice: Undefined index: captchawav in /var/www/vhosts/wilserv.net/httpdocs/test/captcha.php on line 25
Notice: Undefined index: SCRIPT_URL in /var/www/vhosts/wilserv.net/httpdocs/test/captcha.php on line 59
Notice: Undefined index: SCRIPT_URL in /var/www/vhosts/wilserv.net/httpdocs/test/captcha.php on line 60
Notice: Undefined index: send in /var/www/vhosts/wilserv.net/httpdocs/test/test.php on line 17
Here is captcha.php:
<?php
// There had better be NO BLANK LINES OR ANYTHING ELSE
// before the preceding line!
// Boutell's Simple PHP Captcha.
// Copyright 2007, Thomas Boutell and Boutell.Com, Inc.
// Permission granted to use and modify this code as you
// see fit, provided that you do not represent this code
// as your own work.
// Otherwise, feel free to profit from this code
// in any way you wish.
// NO CHANGES REQUIRED HERE
// All settings are in captcha-settings.php, so that you can
// install an upgraded version of captcha.php without losing them.
require 'captcha-settings.php';
session_start();
if ($_GET['captchaimg']) {
captchaSendImg();
} elseif ($_GET['captchawav']) {
captchaSendWav();
} else {
captchaCode();
}
function captchaImgUrl()
{
global $captchaimg;
return $captchaimg;
}
function captchaWavUrl()
{
global $captchawav;
return $captchawav;
}
function captchaCode()
{
global $captchaimg, $captchawav;
// Don't generate the code twice
if (!$_SESSION['captchacode']) {
// Skip l it is too easily mistaken for 1.
// Skip f, x and s, they are too hard to tell
// apart when spoken.
$chars = "abcdeghijkmnopqrtuvwyz";
$code = "";
$length = mt_rand(5, 7);
for ($i = 0; ($i < $length); $i++) {
$char = substr($chars,
rand(0, strlen($chars) - 1), 1);
$code .= $char;
}
$_SESSION['captchacode'] = $code;
}
$salt = mt_rand(1000000, 2000000);
$captchaimg = $_SERVER['SCRIPT_URL'] . "?captchaimg=1&captchasalt=$salt";
$captchawav = $_SERVER['SCRIPT_URL'] . "?captchawav=1&captchasalt=$salt";
}
function captchaDone()
{
if ($_SESSION['captchacode']) {
unset($_SESSION['captchacode']);
}
}
function captchaSendImg()
{
global $captchaFont;
$code = $_SESSION['captchacode'];
$im = imagecreatetruecolor(200, 50);
imageantialias($im, 1);
$back = imagecolorallocate($im, 255, 255, 255);
$fore = imagecolorallocate($im, 0, 0, 0);
imagefilledrectangle($im, 0, 0, 200, 50, $back);
$x = mt_rand(10, 20);
$y = mt_rand(20, 35);
$length = strlen($code);
for ($i = 0; ($i < $length); $i++) {
$char = substr($code, $i, 1);
$size = mt_rand(0, 4) + 16.0;
$angle = mt_rand(0, -45);
$xoffs = mt_rand(-3, 3);
$yoffs = mt_rand(-5, 5);
imagettftext($im, $size, $angle,
$x + $xoffs, $y + $yoffs,
$fore, $captchaFont, $char);
$x += 23;
$code .= $char;
}
// Now add lots of noise to
// confuse OCR software
$flakes = (200 * 50) / 16;
$flakes = mt_rand($flakes * .8, $flakes * 1.2);
for ($i = 0; ($i < $flakes); $i++) {
$x1 = mt_rand(0, 200);
$y1 = mt_rand(0, 50);
$x2 = $x1 + mt_rand(-2, 2);
$y2 = $y1 + mt_rand(-2, 2);
imageline($im, $x1, $y1, $x2, $y2, $fore);
}
// jpeg is lossy, which is good here, because
// it makes automated analysis of the captcha
// a little more difficult.
header("Content-type: image/jpeg");
imagejpeg($im);
exit(0);
}
function captchaSendWav()
{
global $captchaSounds;
$wav = "RIFF";
# Dummy length for now, we'll patch it
# when we know the final length
$riffLengthOffset = strlen($wav);
$wav .= pack("V", 0);
$wav .= "WAVE";
# Now the format chunk
$wav .= "fmt ";
# Enough room to describe PCM
$wav .= pack("V", 16);
# Select PCM
$wav .= pack("v", 1);
# mono
$wav .= pack("v", 1);
# samplerate
$wav .= pack("V", 22050);
# byterate
$wav .= pack("V", 22050);
# block alignment
$wav .= pack("v", 1);
# bits per sample
$wav .= pack("v", 8);
# Now the data chunk
$wav .= "data";
$code = $_SESSION['captchacode'];
$sound = "";
$change = mt_rand(7000, 10000);
$change /= 10000.0;
for ($i = 0; ($i < strlen($code)); $i++) {
$char = substr($code, $i, 1);
$lsound = file_get_contents("$captchaSounds/$char.ub");
$llen = strlen($lsound);
$nsound = "";
$prev = 0;
$smoothFrequency = mt_rand(200, 300);
for ($j = 0; ($j < $llen); $j++) {
$byte = ord(substr($lsound, $j, 1));
# Change volume slightly to thwart attempts
# to just recognize the same series of bytes
$byte *= $change;
# Smooth in an occasional extra byte to thwart
# attempts to simply calculate letter lengths
if (mt_rand(0, $smoothFrequency) == 0) {
$smooth = ($byte + $prev) / 2.0;
$nsound .= pack("C", $smooth);
}
$nsound .= pack("C", $byte);
$prev = $byte;
}
$sound .= $nsound;
}
$wav .= pack("V", strlen($sound));
$wav .= $sound;
substr_replace($wav, pack("V", strlen($wav) - 8),
$riffLengthOffset, 4);
$clength = strlen($wav);
header("Content-length: $clength");
header("Content-type: audio/wav");
echo($wav);
exit(0);
}
function captchaBasePath()
{
$src = __FILE__;
$path = preg_replace('/\/[^\/]+$/', '', $src);
return $path;
}
?>
Any idea why these errors would occur?
