스팸글 자동등록 방지

auth_code.php

01.<?

02.session_start();

03.$_SESSION['key'] = rand(0,9).rand(0,9).rand(0,9).rand(0,9);

04.header("Content-type: image/png");

05.$arry = array('arial.ttf','cour.ttf','verdana.ttf','tahoma.ttf');

06.$wdth = 110; $hght = 50;

07.$img = imagecreate($wdth,$hght);

08.$clr_bckgrnd = imagecolorallocate($img,255,255,255);

09.$clr_frgrnd1 = imagecolorallocate($img,rand(10,255),rand(10,255),rand(10,255));

10.$clr_frgrnd2 = imagecolorallocate($img,rand(10,255),rand(10,255),rand(10,255));

11.$clr_frgrnd3 = imagecolorallocate($img,rand(10,255),rand(10,255),rand(10,255));

12.$clr_frgrnd4 = imagecolorallocate($img,rand(10,255),rand(10,255),rand(10,255));

13.imagefilledrectangle($img,0,0,$wdth,$hght,$clr_bckgrnd);

14.$clr_black = imagecolorallocate($img,200,200,200);

15.// 원그리기 시작위치y 시작위치x 크기 x 크기 y

16.for($i=0;$i<=$wdth;$i+=20){ // 가로 시작점

17.$f = rand(0,$hght);    // 세로 시작점

18.$b = rand(1,3);        // 원의 크기

19.ImageArc ($img, $i, $f, $b, $b, 0, 360, $clr_black); // 원 그리기

20.ImageFill ($img, $i, $f, $clr_black); //그린원에 색채우기

21.}

22.$num = 5;

23.for ($i=$num; $i<=$wdth; $i+=10){  //가로 선

24.imageline($img,$i,0,$i,$hght,$clr_black);

25.}

26.for ($i=$num; $i<=$hght+10; $i+=10){ //세로 선

27.imageline($img,0,$i,$wdth,$i,$clr_black);

28.}

29. 

30.imagettftext($img,rand(20,40),rand(0,10),5,rand(40,50),$clr_frgrnd1,$arry[rand(0,3)] substr($_SESSION['key'],0,1));

31.imagettftext($img,rand(20,40),rand(0,10),30,rand(40,50),$clr_frgrnd2,$arry[rand(0,3)],substr($_SESSION['key'],1,1));

32.imagettftext($img,rand(20,40),rand(0,10),55,rand(40,50),$clr_frgrnd3,$arry[rand(0,3)],substr($_SESSION['key'],2,1));

33.imagettftext($img,rand(20,40),rand(0,10),80,rand(40,50),$clr_frgrnd4,$arry[rand(0,3)],substr($_SESSION['key'],3,1));

34.imagepng($img);

35.imagedestroy($img);

36.?>

 

test.php

1.<form method="post" action="test_ok.php">

2.<img src="auth_code.php"  style="border:1px solid #dddddd"/><br>

3.<input type=text name="authcode" size="15" maxlength="20">

4.<input type="submit" value="전송">

5.</form>

 

test_ok.php

01.<?

02.session_start();

03.if(!$_SESSION['key'] OR $_POST['authcode']!=$_SESSION['key']) {

04.$_SESSION['key'] = rand(0,9).rand(0,9).rand(0,9).rand(0,9);

05.echo "스팸방지키가 잘못 입력되었습니다.";

06.}else{

07.echo "스팸방지키가 정상적으로 입력되었습니다.";

08.}

09.?>

10.<br>

11.<input type="button" value="뒤로" onclick="location.href='test.php'">

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http://mopd.tistory.com/17

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