Server side programming is wonderful as it provides access to lot of resources that client side scripts cant dream of...Database access, files to read and write to, mail programs and other applications on the server...
But Server side scripts are notorious for there slow speed of execution also.So its always a combination of both that triumphs.. Here is a imple perl script to print hello world... and since its a serebvr side script.. after printing "Hello world" it realises that it has entered the world wide web and prints "Hello web" :)
#!/usr/bin/perl
print "Content-type:text/html\n\n";
$first="Hello World";#scalar variable
print $first;
print "<br >";#line break
substr($first,7,10)="eb";#realisation
print $first;
Monday, April 14, 2008
Friday, April 11, 2008
Passing values between Javascript and Vbscript
Very few applications are using Vbscript, but lot of old code exsists that use Vbscript. So its not very difficult to run into a situation where values have to be passed from one to the other. First i was thinking of using a hidden text box to pass values between the two... but its much easier. You can call variables from both, meaning variables are not specific to the scripting langauge as both are client side scripting langauges.
See the following code:
<html>
<body>
<script>
jvalue=confirm('Pass a value to Javascript');
</script>
<script type="text/vbscript">
document.write(lcase(jvalue))
<!--javascript variable used in Vbscript function -->
vvalue=ucase("vbscript here")
</script>
<script>
alert(vvalue)
</script>
<!--Vbscript variable used in Javascript function -->
<input type='hidden' name='passval'>
<!--no need of hidden text box-->
</body>
</html>
This example shows how one can use variables from javascript in vbscript and also vice-versa.
The situation is very different when values are to be passed between a client side script and a server side script.
See the following code:
<html>
<body>
<script>
jvalue=confirm('Pass a value to Javascript');
</script>
<script type="text/vbscript">
document.write(lcase(jvalue))
<!--javascript variable used in Vbscript function -->
vvalue=ucase("vbscript here")
</script>
<script>
alert(vvalue)
</script>
<!--Vbscript variable used in Javascript function -->
<input type='hidden' name='passval'>
<!--no need of hidden text box-->
</body>
</html>
This example shows how one can use variables from javascript in vbscript and also vice-versa.
The situation is very different when values are to be passed between a client side script and a server side script.
Thursday, April 3, 2008
Hard coding username and password
If you are thinking of hardcoding username and password.. pls dont do it. Here are some sane reasons not to do it:
- When the password expires, its got to be reset...if its hard coded, they have got to search where the elusive password has been coded. Add to this the fact that the password will be encrypted and hardcoded---they have to break the code to get to the password...
- Code is not the place to put ur passwords in.. For example i know of a very widely used business application which will work only with the vendor provided software....so how secure is your application?
- Hard coded paswords cant be changed with changing employes. So you never know..
Ok even after this if you want to hard code the password... please make sure you comment your code properly...
Sunday, March 9, 2008
Capuccino coffee
Leaf design on the coffee. It was capuccino coffee.
And some funny new street lights that hey came up at the new lamp company.
And some funny new street lights that hey came up at the new lamp company.
Saturday, March 8, 2008
Cows and bulls practical
The correct guess to try in the practical version of cows and bulls encrypted is 6598. the number of cows and bulls are displayed in the alert box. The logic is simple....the RSA public key cryptography is used with a preset key of 17 and 3233. The example is taken right out of wikipedia. The guesses that are entered are taken and there position is appended to it(i.e, 1,2,3 and 4). This value is then encrypted and compared with the values stored in arrays 'a' and 'b', a has the values that are bulls and b has all the cows. The values are given below:
bulls
64-1577
53-652
92-2762
81-1485
cows
63-2909
62-1162
61-178
54-1978
52-3094
51-2985
94-205
93-456
91-3157
84-1820
83-3185
82-2661
The game in practicallity would have to have more number of such encrypted arrays. One of them would have to be choosen randomly. However, the randomess doesnt need to be hidden.If a higher degree of encryption is needed, the keys can be changed and the arrays and the function that is used to encrypt can be changed at the server side when the javascript is generated.
bulls
64-1577
53-652
92-2762
81-1485
cows
63-2909
62-1162
61-178
54-1978
52-3094
51-2985
94-205
93-456
91-3157
84-1820
83-3185
82-2661
The game in practicallity would have to have more number of such encrypted arrays. One of them would have to be choosen randomly. However, the randomess doesnt need to be hidden.If a higher degree of encryption is needed, the keys can be changed and the arrays and the function that is used to encrypt can be changed at the server side when the javascript is generated.
Tuesday, March 4, 2008
Cow and bulls-javascript posible?
This post assumes you know what a trap door function is, and also about Gautham B Pai... and his cow and bulls game and the challenges he seems to be facing with javascript....
The challenge is to make the game completely using javascript and only upload the results back to the server. This seems to be one of the ways to "Make the game run completely using javascript"....
First all the numbers 0 to nine are encrypted using a trap door function such as RSA. The numbers have to written in words(filled with blanks to make all the numeric words equal) to prevent easily breaking the code by trial and error. If further higher levels of security are needed the number combinations should be used.
Ok so basically we have an array of encoded numbers in word form.We also have the public key to encrypt the guesses from the user. Based on the output from random number function, a variable set is choosen from the array. The values entered by the user are encrypted using the public key and compared with value stored in the choosen variable set. If both are equal, the results are sent to server...
This method can be effective if the public key seed value is defined by the server at the time the javascript is generated.This ensures the effective and secure game plan...!!!!!!! Since the player cant know the actual value of the number even if he knows the encrypted form of the number this should work..
The challenge is to make the game completely using javascript and only upload the results back to the server. This seems to be one of the ways to "Make the game run completely using javascript"....
First all the numbers 0 to nine are encrypted using a trap door function such as RSA. The numbers have to written in words(filled with blanks to make all the numeric words equal) to prevent easily breaking the code by trial and error. If further higher levels of security are needed the number combinations should be used.
Ok so basically we have an array of encoded numbers in word form.We also have the public key to encrypt the guesses from the user. Based on the output from random number function, a variable set is choosen from the array. The values entered by the user are encrypted using the public key and compared with value stored in the choosen variable set. If both are equal, the results are sent to server...
This method can be effective if the public key seed value is defined by the server at the time the javascript is generated.This ensures the effective and secure game plan...!!!!!!! Since the player cant know the actual value of the number even if he knows the encrypted form of the number this should work..
Subscribe to:
Posts (Atom)