<?php
/**
* Project: Securimage: A PHP class for creating and managing form CAPTCHA images<br />
* File: securimage.php<br />
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or any later version.<br /><br />
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.<br /><br />
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA<br /><br />
*
* Any modifications to the library should be indicated clearly in the source code
* to inform users that the changes are not a part of the original software.<br /><br />
*
* If you found this script useful, please take a quick moment to rate it.<br />
* http://www.hotscripts.com/rate/49400.html Thanks.
*
* @link http://www.phpcaptcha.org Securimage PHP CAPTCHA
* @link http://www.phpcaptcha.org/latest.zip Download Latest Version
* @link http://www.phpcaptcha.org/Securimage_Docs/ Online Documentation
* @copyright 2009 Drew Phillips
* @author Drew Phillips <drew@drew-phillips.com>
* @version 2.0.1 BETA (December 6th, 2009)
* @package Securimage
*
*/
/**
ChangeLog
2.0.1
- Add support for browsers with cookies disabled (requires php5, sqlite) maps users to md5 hashed ip addresses and md5 hashed codes for security
- Add fallback to gd fonts if ttf support is not enabled or font file not found (Mike Challis http://www.642weather.com/weather/scripts.php)
- Check for previous definition of image type constants (Mike Challis)
- Fix mime type settings for audio output
- Fixed color allocation issues with multiple colors and background images, consolidate allocation to one function
- Ability to let codes expire after a given length of time
- Allow HTML color codes to be passed to Securimage_Color (suggested by Mike Challis)
2.0.0
- Add mathematical distortion to characters (using code from HKCaptcha)
- Improved session support
- Added Securimage_Color class for easier color definitions
- Add distortion to audio output to prevent binary comparison attack (proposed by Sven "SavageTiger" Hagemann [insecurity.nl])
- Flash button to stream mp3 audio (Douglas Walsh www.douglaswalsh.net)
- Audio output is mp3 format by default
- Change font to AlteHaasGrotesk by yann le coroller
- Some code cleanup
1.0.4 (unreleased)
- Ability to output audible codes in mp3 format to stream from flash
1.0.3.1
- Error reading from wordlist in some cases caused words to be cut off 1 letter short
1.0.3
- Removed shadow_text from code which could cause an undefined property error due to removal from previous version
1.0.2
- Audible CAPTCHA Code wav files
- Create codes from a word list instead of random strings
1.0
- Added the ability to use a selected character set, rather than a-z0-9 only.
- Added the multi-color text option to use different colors for each letter.
- Switched to automatic session handling instead of using files for code storage
- Added GD Font support if ttf support is not available. Can use internal GD fonts or load new ones.
- Added the ability to set line thickness
- Added option for drawing arced lines over letters
- Added ability to choose image type for output
*/
/**
* Output images in JPEG format
*/
if (!defined('SI_IMAGE_JPEG'))
define('SI_IMAGE_JPEG', 1);
/**
* Output images in PNG format
*/
if (!defined('SI_IMAGE_PNG'))
define('SI_IMAGE_PNG', 2);
/**
* Output images in GIF format (not recommended)
* Must have GD >= 2.0.28!
*/
if (!defined('SI_IMAGE_GIF'))
define('SI_IMAGE_GIF', 3);
/**
* Securimage CAPTCHA Class.
*
* @package Securimage
* @subpackage classes
*
*/
class Securimage {
/**
* The desired width of the CAPTCHA image.
*
* @var int
*/
var $image_width;
/**
* The desired width of the CAPTCHA image.
*
* @var int
*/
var $image_height;
/**
* The image format for output.<br />
* Valid options: SI_IMAGE_PNG, SI_IMAGE_JPG, SI_IMAGE_GIF
*
* @var int
*/
var $image_type;
/**
* The length of the code to generate.
*
* @var int
*/
var $code_length;
/**
* The character set for individual characters in the image.<br />
* Letters are converted to uppercase.<br />
* The font must support the letters or there may be problematic substitutions.
*
* @var string
*/
var $charset;
/**
* Create codes using this word list
*
* @var string The path to the word list to use for creating CAPTCHA codes
*/
var $wordlist_file;
/**
* Use wordlist of not
*
* @var bool true to use wordlist file, false to use random code
*/
var $use_wordlist = false;
/**
* Note: Use of GD fonts is not recommended as many distortion features are not available<br />
* The GD font to use.<br />
* Internal gd fonts can be loaded by their number.<br />
* Alternatively, a file path can be given and the font will be loaded from file.
*
* @var mixed
*/
var $gd_font_file;
/**
* The approximate size of the font in pixels.<br />
* This does not control the size of the font because that is determined by the GD font itself.<br />
* This is used to aid the calculations of positioning used by this class.<br />
*
* @var int
*/
var $gd_font_size;
/**
* Use a gd font instead of TTF
*
* @var bool true for gd font, false for TTF
*/
var $use_gd_font;
// Note: These font options below do not apply if you set $use_gd_font to true with the exception of $text_color
/**
* The path to the TTF font file to load.
*
* @var string
*/
var $ttf_file;
/**
* How much to distort image, higher = more distortion.<br />
* Distortion is only available when using TTF fonts.<br />
*
* @var float
*/
var $perturbation;
/**
* The minimum angle in degrees, with 0 degrees being left-to-right reading text.<br />
* Higher values represent a counter-clockwise rotation.<br />
* For example, a value of 90 would result in bottom-to-top reading text.<br />
* This value along with maximum angle distance do not need to be very high with perturbation
*
* @var int
*/
var $text_angle_minimum;
/**
* The minimum angle in degrees, with 0 degrees being left-to-right reading text.<br />
* Higher values represent a counter-clockwise rotation.<br />
* For example, a value of 90 would result in bottom-to-top reading text.
*
* @var int
*/
var $text_angle_maximum;
/**
* The X-Position on the image where letter drawing will begin.<br />
* This value is in pixels from the left side of the image.
*
* @var int
* @deprecated 2.0
*/
var $text_x_start;
/**
* The background color for the image as a Securimage_Color.<br />
*
* @var Securimage_Color
*/
var $image_bg_color;
/**
* Scan this directory for gif, jpg, and png files to use as background images.<br />
* A random image file will be picked each time.<br />
* Change from null to the full path to your directory.<br />
* i.e. var $background_directory = $_SERVER['DOCUMENT_ROOT'] . '/securimage/backgrounds';
* Make sure not to pass a background image to the show function, otherwise this directive is ignored.
*
* @var string
*/
var $background_directory = null; //'./backgrounds';
/**
* The text color to use for drawing characters as a Securimage_Color.<br />
* This value is ignored if $use_multi_text is set to true.<br />
* Make sure this contrasts well with the background color or image.<br />
*
* @see Securimage::$use_multi_text
* @var Securimage_Color
*/
var $text_color;
/**
* Set to true to use multiple colors for each character.
*
* @see Securimage::$multi_text_color
* @var boolean
*/
var $use_multi_text;
/**
* Array of Securimage_Colors which will be randomly selected for each letter.<br />
*
* @var array
*/
var $multi_text_color;
/**
* Set to true to make the characters appear transparent.
*
* @see Securimage::$text_transparency_percentage
* @var boolean
*/
var $use_transparent_text;
/**
* The percentage of transparency, 0 to 100.<br />
* A value of 0 is completely opaque, 100 is completely transparent (invisble)
*
* @see Securimage::$use_transparent_text
* @var int
*/
var $text_transparency_percentage;
// Line options
/**
* Draw vertical and horizontal lines on the image.
*
* @see Securimage::$line_color
* @see Securimage::$draw_lines_over_text
* @var boolean
*/
var $num_lines;
/**
* Color of lines drawn over text
*
* @var string
*/
var $line_color;
/**
* Draw the lines over the text.<br />
* If fales lines will be drawn before putting the text on the image.
*
* @var boolean
*/
var $draw_lines_over_text;
/**
* Text to write at the bottom corner of captcha image
*
* @since 2.0
* @var string Signature text
*/
var $image_signature;
/**
* Color to use for writing signature text
*
* @since 2.0
* @var Securimage_Color
*/
var $signature_color;
/**
* Full path to the WAV files to use to make the audio files, include trailing /.<br />
* Name Files [A-Z0-9].wav
*
* @since 1.0.1
* @var string
*/
var $audio_path;
/**
* Type of audio file to generate (mp3 or wav)
*
* @var string
*/
var $audio_format;
/**
* The session name to use if not the default. Blank for none
*
* @see http://php.net/session_name
* @since 2.0
* @var string
*/
var $session_name = '';
/**
* The amount of time in seconds that a code remains valid.<br />
* Any code older than this number will be considered invalid even if entered correctly.<br />
* Any non-numeric or value less than 1 disables this functionality.
*
* @var int
*/
var $expiry_time;
/**
* Path to the file to use for storing codes for users.<br />
* THIS FILE MUST ABSOLUTELY NOT BE ACCESSIBLE FROM A WEB BROWSER!!<br />
* Put this file in a directory below the web root or one that is restricted (i.e. an apache .htaccess file with deny from all)<br />
* If you cannot meet those requirements your forms may not be completely protected.<br />
* You could obscure the database file name but this is also not recommended.
*
* @var string
*/
var $sqlite_database;
/**
* Use an SQLite database for storing codes as a backup to sessions.<br />
* Note: Sessions will still be used
*/
var $use_sqlite_db;
//END USER CONFIGURATION
//There should be no need to edit below unless you really know what you are doing.
/**
* The gd image resource.
*
* @access private
* @var resource
*/
var $im;
/**
* Temporary image for rendering
*
* @access private
* @var resource
*/
var $tmpimg;
/**
* Internal scale factor for anti-alias @hkcaptcha
*
* @access private
* @since 2.0
* @var int
*/
var $iscale; // internal scale factor for anti-alias @hkcaptcha
/**
* The background image resource
*
* @access private
* @var resource
*/
var $bgimg;
/**
* The code generated by the script
*
* @access private
* @var string
*/
var $code;
/**
* The code that was entered by the user
*
* @access private
* @var string
*/
var $code_entered;
/**
* Whether or not the correct code was entered
*
* @access private
* @var boolean
*/
var $correct_code;
/**
* Handle to SQLite database
*
* @access private
* @var resource
*/
var $sqlite_handle;
/**
* Color resource for image line color
*
* @access private
* @var int
*/
var $gdlinecolor;
/**
* Array of colors for multi colored codes
*
* @access private
* @var array
*/
var $gdmulticolor;
/**
* Color resource for image font color
*
* @access private
* @var int
*/
var $gdtextcolor;
/**
* Color resource for image signature color
*
* @access private
* @var int
*/
var $gdsignaturecolor;
/**
* Color resource for image background color
*
* @access private
* @var int
*/
var $gdbgcolor;
/**
* Class constructor.<br />
* Because the class uses sessions, this will attempt to start a session if there is no previous one.<br />
* If you do not start a session before calling the class, the constructor must be called before any
* output is sent to the browser.
*
* <code>
* $securimage = new Securimage();
* </code>
*
*/
function Securimage()
{
// Initialize session or attach to existing
if ( session_id() == '' ) { // no session has been started yet, which is needed for validation
if (trim($this->session_name) != '') {
session_name($this->session_name); // set session name if provided
}
session_start();
}
// Set Default Values
$this->image_width = 230;
$this->image_height = 80;
$this->image_type = SI_IMAGE_PNG;
$this->code_length = 6;
$this->charset = 'ABCDEFGHKLMNPRSTUVWYZabcdefghklmnprstuvwyz23456789';
$this->wordlist_file = './words/words.txt';
$this->use_wordlist = false;
$this->gd_font_file = 'gdfonts/automatic.gdf';
$this->use_gd_font = false;
$this->gd_font_size = 24;
$this->text_x_start = 15;
$this->ttf_file = './AHGBold.ttf';
$this->perturbation = 0.75;
$this->iscale = 5;
$this->text_angle_minimum = 0;
$this->text_angle_maximum = 0;
$this->image_bg_color = new Securimage_Color(0xff, 0xff, 0xff);
$this->text_color = new Securimage_Color(0x3d, 0x3d, 0x3d);
$this->multi_text_color = array(new Securimage_Color(0x0, 0x20, 0xCC),
new Securimage_Color(0x0, 0x30, 0xEE),
new Securimage_color(0x0, 0x40, 0xCC),
new Securimage_Color(0x0, 0x50, 0xEE),
new Securimage_Color(0x0, 0x60, 0xCC));
$this->use_multi_text = false;
$this->use_transparent_text = false;
$this->text_transparency_percentage = 30;
$this->num_lines = 10;
$this->line_color = new Securimage_Color(0x3d, 0x3d, 0x3d);
$this->draw_lines_over_text = true;
$this->image_signature = '';
$this->signature_color = new Securimage_Color(0x20, 0x50, 0xCC);
$this->signature_font = './AHGBold.ttf';
$this->audio_path = './audio/';
$this->audio_format = 'mp3';
$this->session_name = '';
$this->expiry_time = 900;
$this->sqlite_database = 'database/securimage.sqlite';
$this->use_sqlite_db = false;
$this->sqlite_handle = false;
}
/**
* Generate a code and output the image to the browser.
*
* <code>
* <?php
* include 'securimage.php';
* $securimage = new Securimage();
* $securimage->show('bg.jpg');
* ?>
* </code>
*
* @param string $background_image The path to an image to use as the background for the CAPTCHA
*/
function show($background_image = "")
{
if($background_image != "" && is_readable($background_image)) {
$this->bgimg = $background_image;
}
$this->doImage();
}
/**
* Validate the code entered by the user.
*
* <code>
* $code = $_POST['code'];
* if ($securimage->check($code) == false) {
* die("Sorry, the code entered did not match.");
* } else {
* $valid = true;
* }
* </code>
* @param string $code The code the user entered
* @return boolean true if the code was correct, false if not
*/
function check($code)
{
$this->code_entered = $code;
$this->validate();
return $this->correct_code;
}
/**
* Output audio file with HTTP headers to browser
*
* <code>
* $sound = new Securimage();
* $sound->audio_format = 'mp3';
* $sound->outputAudioFile();
* </code>
*
* @since 2.0
*/
function outputAudioFile()
{
if (strtolower($this->audio_format) == 'wav') {
header('Content-type: audio/x-wav');
$ext = 'wav';
} else {
header('Content-type: audio/mpeg'); // default to mp3
$ext = 'mp3';
}
header("Content-Disposition: attachment; filename=\"securimage_audio.{$ext}\"");
header('Cache-Control: no-store, no-cache, must-revalidate');
header('Expires: Sun, 1 Jan 2000 12:00:00 GMT');
header('Last-Modified: ' . gmdate('D, d M Y H:i:s') . 'GMT');
$audio = $this->getAudibleCode($ext);
header('Content-Length: ' . strlen($audio));
echo $audio;
exit;
}
/**
* Generate and output the image
*
* @access private
*
*/
function doImage()
{
if ($this->use_gd_font == true) {
$this->iscale = 1;
}
if($this->use_transparent_text == true || $this->bgimg != "") {
$this->im = imagecreatetruecolor($this->image_width, $this->image_height);
$this->tmpimg = imagecreatetruecolor($this->image_width * $this->iscale, $this->image_height * $this->iscale);
} else { //no transparency
$this->im = imagecreate($this->image_width, $this->image_height);
$this->tmpimg = imagecreate($this->image_width * $this->iscale, $this->image_height * $this->iscale);
}
$this->allocateColors();
imagepalettecopy($this->tmpimg, $this->im);
$this->setBackground();
$this->createCode();
if (!$this->draw_lines_over_text && $this->num_lines > 0) $this->drawLines();
$this->drawWord();
if ($this->use_gd_font == false && is_readable($this->ttf_file)) $this->distortedCopy();
if ($this->draw_lines_over_text && $this->num_lines > 0) $this->drawLines();
if (trim($this->image_signature) != '') $this->addSignature();
$this->output();
}
/**
* Allocate all colors that will be used in the CAPTCHA image
*
* @since 2.0.1
* @access private
*/
function allocateColors()
{
// allocate bg color first for imagecreate
$this->gdbgcolor = imagecolorallocate($this->im, $this->image_bg_color->r, $this->image_bg_color->g, $this->image_bg_color->b);
$alpha = intval($this->text_transparency_percentage / 100 * 127);
if ($this->use_transparent_text == true) {
$this->gdtextcolor = imagecolorallocatealpha($this->im, $this->text_color->r, $this->text_color->g, $this->text_color->b, $alpha);
$this->gdlinecolor = imagecolorallocatealpha($this->im, $this->line_color->r, $this->line_color->g, $this->line_color->b, $alpha);
} else {
$this->gdtextcolor = imagecolorallocate($this->im, $this->text_color->r, $this->text_color->g, $this->text_color->b);
$this->gdlinecolor = imagecolorallocate($this->im, $this->line_color->r, $this->line_color->g, $this->line_color->b);
}
$this->gdsignaturecolor = imagecolorallocate($this->im, $this->signature_color->r, $this->signature_color->g, $this->signature_color->b);
if ($this->use_multi_text == true) {
$this->gdmulticolor = array();
foreach($this->multi_text_color as $color) {
if ($this->use_transparent_text == true) {
$this->gdmulticolor[] = imagecolorallocatealpha($this->im, $color->r, $color->g, $color->b, $alpha);
} else {
$this->gdmulticolor[] = imagecolorallocate($this->im, $color->r, $color->g, $color->b);
}
}
}
}
/**
* Set the background of the CAPTCHA image
*
* @access private
*
*/
function setBackground()
{
imagefilledrectangle($this->im, 0, 0, $this->image_width * $this->iscale, $this->image_height * $this->iscale, $this->gdbgcolor);
imagefilledrectangle($this->tmpimg, 0, 0, $this->image_width * $this->iscale, $this->image_height * $this->iscale, $this->gdbgcolor);
if ($this->bgimg == '') {
if ($this->background_directory != null && is_dir($this->background_directory) && is_readable($this->background_directory)) {
$img = $this->getBackgroundFromDirectory();
if ($img != false) {
$this->bgimg = $img;
}
}
}
$dat = @getimagesize($this->bgimg);
if($dat == false) {
return;
}
switch($dat[2]) {
case 1: $newim = @imagecreatefromgif($this->bgimg); break;
case 2: $newim = @imagecreatefromjpeg($this->bgimg); break;
case 3: $newim = @imagecreatefrompng($this->bgimg); break;
case 15: $newim = @imagecreatefromwbmp($this->bgimg); break;
case 16: $newim = @imagecreatefromxbm($this->bgimg); break;
default: return;
}
if(!$newim) return;
imagecopyresized($this->im, $newim, 0, 0, 0, 0, $this->image_width, $this->image_height, imagesx($newim), imagesy($newim));
}
/**
* Return the full path to a random gif, jpg, or png from the background directory.
*
* @access private
* @see Securimage::$background_directory
* @return mixed false if none found, string $path if found
*/
function getBackgroundFromDirectory()
{
$images = array();
if ($dh = opendir($this->background_directory)) {
while (($file = readdir($dh)) !== false) {
if (preg_match('/(jpg|gif|png)$/i', $file)) $images[] = $file;
}
closedir($dh);
if (sizeof($images) > 0) {
return rtrim($this->background_directory, '/') . '/' . $images[rand(0, sizeof($images)-1)];
}
}
return false;
}
/**
* Draw random curvy lines over the image<br />
* Modified code from HKCaptcha
*
* @since 2.0
* @access private
*
*/
function drawLines()
{
for ($line = 0; $line < $this->num_lines; ++$line) {
$x = $this->image_width * (1 + $line) / ($this->num_lines + 1);
$x += (0.5 - $this->frand()) * $this->image_width / $this->num_lines;
$y = rand($this->image_height * 0.1, $this->image_height * 0.9);
$theta = ($this->frand()-0.5) * M_PI * 0.7;
$w = $this->image_width;
$len = rand($w * 0.4, $w * 0.7);
$lwid = rand(0, 2);
$k = $this->frand() * 0.6 + 0.2;
$k = $k * $k * 0.5;
$phi = $this->frand() * 6.28;
$step = 0.5;
$dx = $step * cos($theta);
$dy = $step * sin($theta);
$n = $len / $step;
$amp = 1.5 * $this->frand() / ($k + 5.0 / $len);
$x0 = $x - 0.5 * $len * cos($theta);
$y0 = $y - 0.5 * $len * sin($theta);
$ldx = round(-$dy * $lwid);
$ldy = round($dx * $lwid);
for ($i = 0; $i < $n; ++$i) {
$x = $x0 + $i * $dx + $amp * $dy * sin($k * $i * $step + $phi);
$y = $y0 + $i * $dy - $amp * $dx * sin($k * $i * $step + $phi);
imagefilledrectangle($this->im, $x, $y, $x + $lwid, $y + $lwid, $this->gdlinecolor);
}
}
}
/**
* Draw the CAPTCHA code over the image
*
* @access private
*
*/
function drawWord()
{
$width2 = $this->image_width * $this->iscale;
$height2 = $this->image_height * $this->iscale;
if ($this->use_gd_font == true || !is_readable($this->ttf_file)) {
if (!is_int($this->gd_font_file)) { //is a file name
$font = @imageloadfont($this->gd_font_file);
if ($font == false) {
trigger_error("Failed to load GD Font file {$this->gd_font_file} ", E_USER_WARNING);
return;
}
} else { //gd font identifier
$font = $this->gd_font_file;
}
imagestring($this->im, $font, $this->text_x_start, ($this->image_height / 2) - ($this->gd_font_size / 2), $this->code, $this->gdtextcolor);
} else { //ttf font
$font_size = $height2 * .35;
$bb = imagettfbbox($font_size, 0, $this->ttf_file, $this->code);
$tx = $bb[4] - $bb[0];
$ty = $bb[5] - $bb[1];
$x = floor($width2 / 2 - $tx / 2 - $bb[0]);
$y = round($height2 / 2 - $ty / 2 - $bb[1]);
$strlen = strlen($this->code);
if (!is_array($this->multi_text_color)) $this->use_multi_text = false;
if ($this->use_multi_text == false && $this->text_angle_minimum == 0 && $this->text_angle_maximum == 0) { // no angled or multi-color characters
imagettftext($this->tmpimg, $font_size, 0, $x, $y, $this->gdtextcolor, $this->ttf_file, $this->code);
} else {
for($i = 0; $i < $strlen; ++$i) {
$angle = rand($this->text_angle_minimum, $this->text_angle_maximum);
$y = rand($y - 5, $y + 5);
if ($this->use_multi_text == true) {
$font_color = $this->gdmulticolor[rand(0, sizeof($this->gdmulticolor) - 1)];
} else {
$font_color = $this->gdtextcolor;
}
$ch = $this->code{$i};
imagettftext($this->tmpimg, $font_size, $angle, $x, $y, $font_color, $this->ttf_file, $ch);
// estimate character widths to increment $x without creating spaces that are too large or too small
// these are best estimates to align text but may vary between fonts
// for optimal character widths, do not use multiple text colors or character angles and the complete string will be written by imagettftext
if (strpos('abcdeghknopqsuvxyz', $ch) !== false) {
$min_x = $font_size - ($this->iscale * 6);
$max_x = $font_size - ($this->iscale * 6);
} else if (strpos('ilI1', $ch) !== false) {
$min_x = $font_size / 5;
$max_x = $font_size / 3;
} else if (strpos('fjrt', $ch) !== false) {
$min_x = $font_size - ($this->iscale * 12);
$max_x = $font_size - ($this->iscale * 12);
} else if ($ch == 'wm') {
$min_x = $font_size;
$max_x = $font_size + ($this->iscale * 3);
} else { // numbers, capitals or unicode
$min_x = $font_size + ($this->iscale * 2);
$max_x = $font_size + ($this->iscale * 5);
}
$x += rand($min_x, $max_x);
} //for loop
} // angled or multi-color
} //else ttf font
//$this->im = $this->tmpimg;
//$this->output();
} //function
/**
* Warp text from temporary image onto final image.<br />
* Modified for securimage
*
* @access private
* @since 2.0
* @author Han-Kwang Nienhuys modified
* @copyright Han-Kwang Neinhuys
*
*/
function distortedCopy()
{
$numpoles = 3; // distortion factor
// make array of poles AKA attractor points
for ($i = 0; $i < $numpoles; ++$i) {
$px[$i] = rand($this->image_width * 0.3, $this->image_width * 0.7);
$py[$i] = rand($this->image_height * 0.3, $this->image_height * 0.7);
$rad[$i] = rand($this->image_width * 0.4, $this->image_width * 0.7);
$tmp = -$this->frand() * 0.15 - 0.15;
$amp[$i] = $this->perturbation * $tmp;
}
$bgCol = imagecolorat($this->tmpimg, 0, 0);
$width2 = $this->iscale * $this->image_width;
$height2 = $this->iscale * $this->image_height;
imagepalettecopy($this->im, $this->tmpimg); // copy palette to final image so text colors come across
// loop over $img pixels, take pixels from $tmpimg with distortion field
for ($ix = 0; $ix < $this->image_width; ++$ix) {
for ($iy = 0; $iy < $this->image_height; ++$iy) {
$x = $ix;
$y = $iy;
for ($i = 0; $i < $numpoles; ++$i) {
$dx = $ix - $px[$i];
$dy = $iy - $py[$i];
if ($dx == 0 && $dy == 0) continue;
$r = sqrt($dx * $dx + $dy * $dy);
if ($r > $rad[$i]) continue;
$rscale = $amp[$i] * sin(3.14 * $r / $rad[$i]);
$x += $dx * $rscale;
$y += $dy * $rscale;
}
$c = $bgCol;
$x *= $this->iscale;
$y *= $this->iscale;
if ($x >= 0 && $x < $width2 && $y >= 0 && $y < $height2) {
$c = imagecolorat($this->tmpimg, $x, $y);
}
if ($c != $bgCol) { // only copy pixels of letters to preserve any background image
imagesetpixel($this->im, $ix, $iy, $c);
}
}
}
}
/**
* Create a code and save to the session
*
* @access private
* @since 1.0.1
*
*/
function createCode()
{
$this->code = false;
if ($this->use_wordlist && is_readable($this->wordlist_file)) {
$this->code = $this->readCodeFromFile();
}
if ($this->code == false) {
$this->code = $this->generateCode($this->code_length);
}
$this->saveData();
}
/**
* Generate a code
*
* @access private
* @param int $len The code length
* @return string
*/
function generateCode($len)
{
$code = '';
for($i = 1, $cslen = strlen($this->charset); $i <= $len; ++$i) {
$code .= $this->charset{rand(0, $cslen - 1)};
}
return $code;
}
/**
* Reads a word list file to get a code
*
* @access private
* @since 1.0.2
* @return mixed false on failure, a word on success
*/
function readCodeFromFile()
{
$fp = @fopen($this->wordlist_file, 'rb');
if (!$fp) return false;
$fsize = filesize($this->wordlist_file);
if ($fsize < 32) return false; // too small of a list to be effective
if ($fsize < 128) {
$max = $fsize; // still pretty small but changes the range of seeking
} else {
$max = 128;
}
fseek($fp, rand(0, $fsize - $max), SEEK_SET);
$data = fread($fp, 128); // read a random 128 bytes from file
fclose($fp);
$data = preg_replace("/\r?\n/", "\n", $data);
$start = strpos($data, "\n", rand(0, 100)) + 1; // random start position
$end = strpos($data, "\n", $start); // find end of word
return strtolower(substr($data, $start, $end - $start)); // return substring in 128 bytes
}
/**
* Output image to the browser
*
* @access private
*
*/
function output()
{
header("Expires: Mon, 26 Jul 1997 05:00:00 GMT");
header("Last-Modified: " . gmdate("D, d M Y H:i:s") . "GMT");
header("Cache-Control: no-store, no-cache, must-revalidate");
header("Cache-Control: post-check=0, pre-check=0", false);
header("Pragma: no-cache");
switch($this->image_type)
{
case SI_IMAGE_JPEG:
header("Content-Type: image/jpeg");
imagejpeg($this->im, null, 90);
break;
case SI_IMAGE_GIF:
header("Content-Type: image/gif");
imagegif($this->im);
break;
default:
header("Content-Type: image/png");
imagepng($this->im);
break;
}
imagedestroy($this->im);
exit;
}
/**
* Get WAV or MP3 file data of the spoken code.<br />
* This is appropriate for output to the browser as audio/x-wav or audio/mpeg
*
* @since 1.0.1
* @return string WAV or MP3 data
*
*/
function getAudibleCode($format = 'wav')
{
$letters = array();
$code = $this->getCode();
if ($code == '') {
$this->createCode();
$code = $this->getCode();
}
for($i = 0; $i < strlen($code); ++$i) {
$letters[] = $code{$i};
}
if ($format == 'mp3') {
return $this->generateMP3($letters);
} else {
return $this->generateWAV($letters);
}
}
/**
* Set the path to the audio directory.<br />
*
* @since 1.0.4
* @return bool true if the directory exists and is readble, false if not
*/
function setAudioPath($audio_directory)
{
if (is_dir($audio_directory) && is_readable($audio_directory)) {
$this->audio_path = $audio_directory;
return true;
} else {
return false;
}
}
/**
* Save the code in the session
*
* @access private
*
*/
function saveData()
{
$_SESSION['securimage_code_value'] = strtolower($this->code);
$_SESSION['securimage_code_ctime'] = time();
$this->saveCodeToDatabase();
}
/**
* Validate the code to the user code
*
* @access private
*
*/
function validate()
{
// retrieve code from session, if no code exists check sqlite database if supported.
if (isset($_SESSION['securimage_code_value']) && trim($_SESSION['securimage_code_value']) != '') {
if ($this->isCodeExpired($_SESSION['securimage_code_ctime']) == false) {
$code = $_SESSION['securimage_code_value'];
}
} else if ($this->use_sqlite_db == true && function_exists('sqlite_open')) { // no code in session - may mean user has cookies turned off
$this->openDatabase();
$code = $this->getCodeFromDatabase();
} else {
// session code invalid or non-existant and code not found in sqlite db or sqlite is not available
$code = '';
}
$code = trim(strtolower($code));
$code_entered = trim(strtolower($this->code_entered));
$this->correct_code = false;
if ($code != '') {
if ($code == $code_entered) {
$this->correct_code = true;
$_SESSION['securimage_code_value'] = '';
$_SESSION['securimage_code_ctime'] = '';
$this->clearCodeFromDatabase();
}
}
}
/**
* Get the captcha code
*
* @since 1.0.1
* @return string
*/
function getCode()
{
if (isset($_SESSION['securimage_code_value']) && !empty($_SESSION['securimage_code_value'])) {
return strtolower($_SESSION['securimage_code_value']);
} else {
if ($this->sqlite_handle == false) $this->openDatabase();
return $this->getCodeFromDatabase(); // attempt to get from database, returns empty string if sqlite is not available or disabled
}
}
/**
* Check if the user entered code was correct
*
* @access private
* @return boolean
*/
function checkCode()
{
return $this->correct_code;
}
/**
* Generate a wav file by concatenating individual files
*
* @since 1.0.1
* @access private
* @param array $letters Array of letters to build a file from
* @return string WAV file data
*/
function generateWAV($letters)
{
$data_len = 0;
$files = array();
$out_data = '';
foreach ($letters as $letter) {
$filename = $this->audio_path . strtoupper($letter) . '.wav';
$fp = fopen($filename, 'rb');
$file = array();
$data = fread($fp, filesize($filename)); // read file in
$header = substr($data, 0, 36);
$body = substr($data, 44);
$data = unpack('NChunkID/VChunkSize/NFormat/NSubChunk1ID/VSubChunk1Size/vAudioFormat/vNumChannels/VSampleRate/VByteRate/vBlockAlign/vBitsPerSample', $header);
$file['sub_chunk1_id'] = $data['SubChunk1ID'];
$file['bits_per_sample'] = $data['BitsPerSample'];
$file['channels'] = $data['NumChannels'];
$file['format'] = $data['AudioFormat'];
$file['sample_rate'] = $data['SampleRate'];
$file['size'] = $data['ChunkSize'] + 8;
$file['data'] = $body;
if ( ($p = strpos($file['data'], 'LIST')) !== false) {
// If the LIST data is not at the end of the file, this will probably break your sound file
$info = substr($file['data'], $p + 4, 8);
$data = unpack('Vlength/Vjunk', $info);
$file['data'] = substr($file['data'], 0, $p);
$file['size'] = $file['size'] - (strlen($file['data']) - $p);
}
$files[] = $file;
$data = null;
$header = null;
$body = null;
$data_len += strlen($file['data']);
fclose($fp);
}
$out_data = '';
for($i = 0; $i < sizeof($files); ++$i) {
if ($i == 0) { // output header
$out_data .= pack('C4VC8', ord('R'), ord('I'), ord('F'), ord('F'), $data_len + 36, ord('W'), ord('A'), ord('V'), ord('E'), ord('f'), ord('m'), ord('t'), ord(' '));
$out_data .= pack('VvvVVvv',
16,
$files[$i]['format'],
$files[$i]['channels'],
$files[$i]['sample_rate'],
$files[$i]['sample_rate'] * (($files[$i]['bits_per_sample'] * $files[$i]['channels']) / 8),
($files[$i]['bits_per_sample'] * $files[$i]['channels']) / 8,
$files[$i]['bits_per_sample'] );
$out_data .= pack('C4', ord('d'), ord('a'), ord('t'), ord('a'));
$out_data .= pack('V', $data_len);
}
$out_data .= $files[$i]['data'];
}
$this->scrambleAudioData($out_data, 'wav');
return $out_data;
}
/**
* Randomly modify the audio data to scramble sound and prevent binary recognition.<br />
* Take care not to "break" the audio file by leaving the header data intact.
*
* @since 2.0
* @access private
* @param $data Sound data in mp3 of wav format
*/
function scrambleAudioData(&$data, $format)
{
if ($format == 'wav') {
$start = strpos($data, 'data') + 4; // look for "data" indicator
if ($start === false) $start = 44; // if not found assume 44 byte header
} else { // mp3
$start = 4; // 4 byte (32 bit) frame header
}
$start += rand(1, 64); // randomize starting offset
$datalen = strlen($data) - $start - 256; // leave last 256 bytes unchanged
for ($i = $start; $i < $datalen; $i += 64) {
$ch = ord($data{$i});
if ($ch < 9 || $ch > 119) continue;
$data{$i} = chr($ch + rand(-8, 8));
}
}
/**
* Generate an mp3 file by concatenating individual files
* @since 1.0.4
* @access private
* @param array $letters Array of letters to build a file from
* @return string MP3 file data
*/
function generateMP3($letters)
{
$data_len = 0;
$files = array();
$out_data = '';
foreach ($letters as $letter) {
$filename = $this->audio_path . strtoupper($letter) . '.mp3';
$fp = fopen($filename, 'rb');
$data = fread($fp, filesize($filename)); // read file in
$this->scrambleAudioData($data, 'mp3');
$out_data .= $data;
fclose($fp);
}
return $out_data;
}
/**
* Generate random number less than 1
* @since 2.0
* @access private
* @return float
*/
function frand()
{
return 0.0001*rand(0,9999);
}
/**
* Print signature text on image
*
* @since 2.0
* @access private
*
*/
function addSignature()
{
if ($this->use_gd_font) {
imagestring($this->im, 5, $this->image_width - (strlen($this->image_signature) * 10), $this->image_height - 20, $this->image_signature, $this->gdsignaturecolor);
} else {
$bbox = imagettfbbox(10, 0, $this->signature_font, $this->image_signature);
$textlen = $bbox[2] - $bbox[0];
$x = $this->image_width - $textlen - 5;
$y = $this->image_height - 3;
imagettftext($this->im, 10, 0, $x, $y, $this->gdsignaturecolor, $this->signature_font, $this->image_signature);
}
}
/**
* Get hashed IP address of remote user
*
* @access private
* @since 2.0.1
* @return string
*/
function getIPHash()
{
return strtolower(md5($_SERVER['REMOTE_ADDR']));
}
/**
* Open SQLite database
*
* @access private
* @since 2.0.1
* @return bool true if database was opened successfully
*/
function openDatabase()
{
$this->sqlite_handle = false;
if ($this->use_sqlite_db && function_exists('sqlite_open')) {
$this->sqlite_handle = sqlite_open($this->sqlite_database, 0666, $error);
if ($this->sqlite_handle !== false) {
$res = sqlite_query($this->sqlite_handle, "PRAGMA table_info(codes)");
if (sqlite_num_rows($res) == 0) {
sqlite_query($this->sqlite_handle, "CREATE TABLE codes (iphash VARCHAR(32) PRIMARY KEY, code VARCHAR(32) NOT NULL, created INTEGER)");
}
}
return $this->sqlite_handle != false;
}
return $this->sqlite_handle;
}
/**
* Save captcha code to sqlite database
*
* @access private
* @since 2.0.1
* @return bool true if code was saved, false if not
*/
function saveCodeToDatabase()
{
$success = false;
$this->openDatabase();
if ($this->use_sqlite_db && $this->sqlite_handle !== false) {
$ip = $this->getIPHash();
$time = time();
$code = $_SESSION['securimage_code_value']; // hash code for security - if cookies are disabled the session still exists at this point
$success = sqlite_query($this->sqlite_handle, "INSERT OR REPLACE INTO codes(iphash, code, created) VALUES('$ip', '$code', $time)");
}
return $success !== false;
}
/**
* Get stored captcha code from sqlite database based on ip address hash
*
* @access private
* @since 2.0.1
* @return string captcha code
*/
function getCodeFromDatabase()
{
$code = '';
if ($this->use_sqlite_db && $this->sqlite_handle !== false) {
$ip = $this->getIPHash();
$res = sqlite_query($this->sqlite_handle, "SELECT * FROM codes WHERE iphash = '$ip'");
if ($res && sqlite_num_rows($res) > 0) {
$res = sqlite_fetch_array($res);
if ($this->isCodeExpired($res['created']) == false) {
$code = $res['code'];
}
}
}
return $code;
}
/**
* Delete a code from the database by ip address hash
*
* @access private
* @since 2.0.1
*/
function clearCodeFromDatabase()
{
if ($this->sqlite_handle !== false) {
$ip = $this->getIPHash();
sqlite_query($this->sqlite_handle, "DELETE FROM codes WHERE iphash = '$ip'");
}
}
/**
* Purge codes over a day old from database
*
* @access private
* @since 2.0.1
*/
function purgeOldCodesFromDatabase()
{
if ($this->use_sqlite_db && $this->sqlite_handle !== false) {
$now = time();
$limit = (!is_numeric($this->expiry_time) || $this->expiry_time < 1) ? 86400 : $this->expiry_time;
sqlite_query($this->sqlite_handle, "DELETE FROM codes WHERE $now - created > $limit");
}
}
/**
* Check a code to see if it is expired based on creation time
*
* @access private
* @since 2.0.1
* @param $creation_time unix timestamp of code creation time
* @return bool true if code has expired, false if not
*/
function isCodeExpired($creation_time)
{
$expired = true;
if (!is_numeric($this->expiry_time) || $this->expiry_time < 1) {
$expired = false;
} else if (time() - $creation_time < $this->expiry_time) {
$expired = false;
}
return $expired;
}
} /* class Securimage */
/**
* Color object for Securimage CAPTCHA
*
* @since 2.0
* @package Securimage
* @subpackage classes
*
*/
class Securimage_Color {
/**
* Red component: 0-255
*
* @var int
*/
var $r;
/**
* Green component: 0-255
*
* @var int
*/
var $g;
/**
* Blue component: 0-255
*
* @var int
*/
var $b;
/**
* Create a new Securimage_Color object.<br />
* Specify the red, green, and blue components using their HTML hex code equivalent.<br />
* Example: The code for the HTML color #4A203C is:<br />
* $color = new Securimage_Color(0x4A, 0x20, 0x3C);
*
* @param $red Red component 0-255
* @param $green Green component 0-255
* @param $blue Blue component 0-255
*/
function Securimage_Color($red, $green = null, $blue = null)
{
if ($green == null && $blue == null && preg_match('/^#[a-f0-9]{3,6}$/i', $red)) {
$col = substr($red, 1);
if (strlen($col) == 3) {
$red = str_repeat(substr($col, 0, 1), 2);
$green = str_repeat(substr($col, 1, 1), 2);
$blue = str_repeat(substr($col, 2, 1), 2);
} else {
$red = substr($col, 0, 2);
$green = substr($col, 2, 2);
$blue = substr($col, 4, 2);
}
$red = hexdec($red);
$green = hexdec($green);
$blue = hexdec($blue);
} else {
if ($red < 0) $red = 0;
if ($red > 255) $red = 255;
if ($green < 0) $green = 0;
if ($green > 255) $green = 255;
if ($blue < 0) $blue = 0;
if ($blue > 255) $blue = 255;
}
$this->r = $red;
$this->g = $green;
$this->b = $blue;
}
}