Recently one of the sites I am developing for my self was link spammed. Some unpleasant individual decided that it would be fun to post 160 ‘comments’ spread over all the blog posts. All the comments contained was URL’s. Even more stupid they used BB tags, but as I wrote the site it doesn’t use them.

Any way, obviously this isn’t some thing I want, so I deleted them all with a quick bit of SQL. No one else has posted a comment to the site because like I said, its still under development.

However, it happened once so there is no reason to think it wont happen again. I thought about the problem for a while, and the only solution is to incorporate some kind of humanity check. Because lets face it, its not like some one sat there and entered them all in. Its was some kind of bot.

Now, I don’t really like the ones that ask you to type the letters from some hard to read image. I can do that, no problem but they look ugly, and if the user was colour blind, or any other sight related issue, then you buggered.

So, I have come up with a different solution. The idea is to ask a random question, some thing that’s so easy any every one will know the answer, but unless you can read, you wont know what the answer is.

While I was busy implementing this solution, and believe me it didn’t take very long, another 20 comments of a very similar nature where posted. How annoying is that?

The solution seems to work for now. There have been no more comments since I completed the changes, but then maybe its only time until the bot gets adjusted, time will tell. But I thought other might benefit from having it so here goes, how to add random questions to your site.

Oh, one thing, I am not going to list my questions here, for a start it took me a shockingly long time to think of 30 really really easy questions, and I also don’t want to give a list of the question text and answers away.

So – on with the show. First off you will need 2 tables, one for the questions and one to keep track of what questions you have asked each user.

The questions table is easy, 3 coloums. Question_id, question and answer. The question id is just a unique number, the question and answer are both varchar.

CREATE TABLE `capture_questions` (
  `question_id` bigint(20) unsigned NOT NULL auto_increment,
  `question` varchar(255) NOT NULL default '',
  `answer` varchar(255) NOT NULL default '',
  PRIMARY KEY  (`question_id`)
) ;

Then we have the table used to store the asked questions. This is even less complicated. All you need is 2 fields, one for the question that was asked ID, and one to store the users Session ID.

CREATE TABLE `capture_question_asked` (
  `sid` varchar(60) NOT NULL default '0',
  `qid` bigint(20) unsigned NOT NULL default '0'
);

So far, that’s all easy enough. You fill in the question table with as many questions as you can think of, along the lines of “is the sky blue” with an answer of “yes” or perhaps “What is 25 + 30″ answer, obviously “55″.

Of course you can create the tables and this isn’t going to do a hell of a lot. So, you’ll need a class to deal with it all. This is a copy of the code, though you will notice the use of the functions “performQuery” and “fetchRow”, these are from my own DB layer. They replace the standard MySQL commands by using a wrapper. It makes it easy to port code from one RDBMS to the other. I personally like this solution because its light weight and simple. But it’s a bit beyond the scope of this post.

So, the class? Its got 2 methods: getQuestion and getAnswer. They both take the a single parameter of ‘sid’. This is the session id, but for compatibility it is passed in to the function so it can basically be any thing.

class captureClass extends baseClass {
  function getQuestion($sid) {
    $question = false ;

    $deleteSQL = "DELETE FROM capture_question_asked " ;
    $deleteSQL .= " WHERE sid = '$sid' " ;

    performQuery($deleteSQL) ;

    $selectQuestionSQL = "SELECT question_id, question " ;
    $selectQuestionSQL .= "FROM capture_questions " ;
    $selectQuestionSQL .= "ORDER BY rand(NOW()) LIMIT 0 , 1 " ;

    $selectQuestionQuery = performQuery($selectQuestionSQL) ;

    if ($selectQuestionQuery) {
      if ($row=fetchRow($selectQuestionQuery)) {
        $question = $row['question'] ;
        $qid = $row['question_id'] ;

        $insertSQL = "INSERT INTO capture_question_asked (sid, qid) " ;
        $insertSQL .= "VALUES ('$sid', '$qid') " ;
        performQuery($insertSQL) ;
      }
    }

    return $question ;
  }

  function getAnswer($sid) {
    $answer = '' ;

    $selectQuestionIdSQL = "SELECT qid FROM capture_question_asked " ;
    $selectQuestionIdSQL .= "WHERE sid = '$sid' " ;

    $selectQuestionIdQuery = performQuery($selectQuestionIdSQL) ;

    if ($selectQuestionIdQuery) {
      if ($row=fetchRow($selectQuestionIdQuery)) {
        $qid = $row['qid'] ;
        $selectAnswerSQL = "SELECT answer FROM capture_questions " ;
        $selectAnswerSQL .= " WHERE question_id = '$qid' " ;

        $selectAnswerQuery = performQuery($selectAnswerSQL) ;

        if ($selectAnswerQuery) {
          if ($answerRow=fetchRow($selectAnswerQuery)) {
            $answer = $answerRow['answer'] ;
          }
        }
      }
    }

    return $answer ;
  }
}

How do you use it? Well, when your page displays the form you make a call to getQuestion and display it. For a while I thought about putting the question ID into the page, but only for a couple of seconds as I realised any half decent attempt to beat the system would just replace the ID with one with a known answer, infact as I suspect that the form is not used, simple data “posted” to the page, then it wouldn’t even matter.

That’s why we keep that information in the database.

Any way, once the form is submitted you then ask the class to get the answer for the current session, and compare what the user entered to the correct answer. I’d suggest forcing lower case, or upper case if you want, but basically make the comparison case insensitive.

If the answers don’t match then the person is, well an idiot or a bot. If no answer is available, then some ones messed with the session, or never even used the form. Doesn’t matter which, either way its an error.

I don’t think I will bother to explain the code it self, its really not that complicated. I think maybe the only bit that might seem a bit strange is the sql used to select a question:

  SELECT question_id, question FROM capture_questions
  ORDER BY rand(NOW()) LIMIT 0 , 1

This simply selects a random record from the table, because its ordered by “rand”. This basically means that for each record in the table a random number is generated, and then the records are ordered by the value. Because we only want one question we use the limit to only select the first record, how ever because each time the records are selected they will be in a different order, each time you get a different record cool ha? :-)

I hope this proves to work over time. I’ll have to keep any eye on it. Just to see how it goes. If any one can see any thing wrong with it, well, let me know.

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Today sees the launch of “OneCare”, Microsofts “secrity solution”. Combining firewall, anti-virus and anti-spyware in to one handy package…. but would you trust it?

I guess many people will, and over time we will find out if its a well spent $49.99 or not, but for me? I don’t think so. Microsoft do many things, but I think if you ask any one they will say the same thin: Microsoft don’t really do security.

Microsoft have had a firewall in XP for some time now, and the malicious software removal tool has been on windows update as well. I turn off the firewall, and the remover dosn’t really seem to do any thing. Now maybe I am being unfair, but do you dare, to use OneCare?

The last part of OneCare is the AV, now MS must know a thing or two about virus’, and who knows the OS better then them, but still, at the end of the day Microsoft has been the main victim of Virus attacks for years, why now are they trying to combat the problem?

It seems to me that basicly, no matter how good or bad OneCare actualy is, Microsoft have an uphill fight against there already poor security record. I don’t think I would trust them to keep my important data safe, or my network free from nasties. I just wont, and I suspect a lot of other people will feel the same.

In the corparte sector, where most software is paid for, other names are well estabilished and, well, who wants to say to there boss “I thought we where protected, I installed Microsoft…..” the laugthing would echo down the halls. So, for the home with many free, and perfectly good AV out there (http://www.avast.com/) why would home users pay?

All I can think of is that this is just a Microsoft way to expand a little, not to mention I bet it dosn’t install unless you have a “valid” windows key, the new way to force you to give more money to MS, like they need it?

When it comes to open source the hackers and crackers are doing us a favour, they find the problems and bring them to the attention of the world, where some bright spark will make a fix and let us all have that to. All well and good.

However I think this could also be a problem, because lets face it. Any monkey can download “free” software to use for this or that, with little or no idea how it actually works. They don’t check for fixes and updates, often believing “it will never happen to me”. In part this is because they just don’t see any reason for some one to hack them. But in the modern world where any script kiddie little git can download a virus construction kit, or a bot to run exploits on lists of servers its no longer a case of being targeted. They don’t care who you are, it’s the box they are after.

Recently a friend of mine suffered from this very problem, he didn’t believe he was worth the effort to hack. But simply by using an Open source web app he unwittingly made him self a target. Though a fix was available, he wasn’t aware of it. It was only when the host contacted him about problems that he even realised he’d been exploited.

With the growing popularity of the internet and open source solutions more and more unskilled users are installing software they don’t even understand. Even worse as any one application grows in popularity it grows as a worth while target for the low life script kiddies out there.

The problem has been exacerbated but the simple truth that with modern scripting languages such as PHP it is getting easier and easier to make some thing, being able to hack code together until it works might be fun, and you might make some thing that does the job, but its not a way to make safe secure software.

Most often exploits are based on stupid mistakes, errors that should have been found early on but weren’t because the code evolved, expanded and changed. No design, no planning, just code it until it works. This is the original meaning of “hacking”.

Now, with out mentioning names, I have pulled apart the code used in the CMS the friend I mention earlier used, and with out doubt I can say its poorly written. But it was free, so no one can complain.

I am sure there is some very good open source applications, linux, apache to name a few, but there is even more “open source” that’s just garbage. Just because its free doesn’t mean its good. Just because it popular doesn’t make it better. In fact as far as I can tell, if you want to use open source applications your probably better of choosing one no one else has really bothered with, that why your less likely to become a victim.

Closed source always has the advantage of being a little harder to find the problems, how ever, and this is important. It doesn’t mean its any better. As a friend of mine pointed out, Open source might be easier to hack in some ways, but because of that the problems come to light and generally are fixed quickly. Where as with a closed source application its actually in the interests of the authors to keep any problems hidden, if its not a common problem it may even go unfixed, because the author sees is as being unlikely any one else will ever find it. Or a fix will be bundled up with a later version and thus many people will never even know they could be at risk.

In the end I do believe open source is good for us all, but its important to check regularly for updates, patches and fixes. If you don’t, on your own head be it.

Each day I check out the technology section of the bbc site, ok, its not the most in-depth, or techy site in the world, but it covers interesting stuff.

One interesting article http://news.bbc.co.uk/1/hi/technology/4816520.stm talks about getting a mac to run windows. That in it self is quite cool, but to my mind its the wrong way.

Who wants to put windows on a mac? what’s the point? You can buy PC hardware for less then the mac, and they run windows with out a problem. Well…. kinda.

So, what would be better? Getting OSX to run on a PC. Do that and what you have is some completion to windows with an existing user base, financial backing and at least most of the applications business want.

Business still counts for more of the computer market. Linux has never really broken in to the desk top market, main I think because people “into” linux don’t do gui. Fundamentally linux geeks tend to not believe its worth the effort, so the gui always seems to be less the perfect.

OSX, now that is a desk top platform, to my understanding its based on linux, and a lot of linux apps can be built to run on it. But, like I said, its a mac so it already has a lot of the applications people want and need.

I could be wrong but to me I think this is only the start. I don’t like mac’s. I don’t want a mac, but I see OSX and it look sexy. Maybe if I didn’t need a mac to try it out I’d give it a go, but buying hardware just to run an OS I might not like? I think not.

So, any way, who the hell am I? I have known Shaolin for years, he might have some idea how many, I am on that old darknet site he mentioned, but do me and favour, and don’t look there, please? I look terrible and I’m ashamed :-P

Like Shaolin I to started with the whole computer thing when I was little. The order is a little haszy, but I am fairly sure I had the TI 994A before the little old specy. Though my use of them was a little differant. True, I did for a while spend many hours typeing code to find out later it didn’t work…. but before long I was coding my own stuff. In basic on the TI, and z80 assembler on the specy, pascal and modual 2 to on the Amstrad CPC, 6800 assembler and C on the ST….

TI, Spectrum, Comador, Atari ST, 386 and beyond, I have always live with a computer, though shockingly never games. My first consol was a ps2 and that is only 4 years old.

After many years of bedroom activites I definatly should be ashamed of (all with a keyboard – and check this? no net connection) I emerged in the bright old world, a whole host of dead technology and languages no one has used since the romans under my belt, and windows gaining popularity.

Fast forward, past VB, pal, and various noddy little things and I’m in to Delphi, oh my, was I in to Delphi. For 7 years I lived, breathed and probably bathed in the windows API and OOP. Gone was Delphi’s native event handlers, to slow, give me the raw message cue…. mutli threaded servers, no problem, n-tier CORBA clients… you name it, I did it.

Then I got bored.

But thats ok, no one wants desk top or server applications any more. So, a bit late to the party I had a go at ASP, and damn that stuffs ugly. PHP how ever, now thats the nuts, and thus I entered web development.

Some one once said I’d never be a web developer, but my first ever professional site went live to 2.5 million unique IPs in the first 48 hours, truely one of my proudest hours.

I’ve been doing PHP ever since, MySQL for most part but if its SQL, its all the same. Date in and data out, its all fairly much simple. Introduce some AJAX just to spice it up a bit, and we’re all having fun.

Where I am going from here, nobody knows, but I code, there for I am so what ever happens, what ever changes… I am a programmer :-)