How can I use 128 Bit AES with fixed len output?

Niyazi Toros

Hi,

How can I use 128 Bit AES with fixed Len output using C#?

Example: I need to enter a value that might be a between 1 character to 16 character. And I have to encrypt the data using 128 Bit AES. Output must be 16 character. How do I do that?

Kind Regards

5 Replies

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Amit Gupta10y ago
Accepted answer
Hi Niyazi
You can make string with a fixed lenth of 16 character by using padleft method
String password = 12345;
Srting fixedpwd = password.PadLeft (16, '#');
Here 16 is the total length of string and # used to pad the remaining characters.
For AES encryption you can get the code from the link below
https://msdn.microsoft.com/en-us/library/system.security.cryptography.aesmanaged(v%3Dvs.110).aspx&ei=8594XmK5&lc=en-IN&s=1&m=738&host=www.google.co.in&ts=1463515960&sig=APY536zasIHpWnQx84t0m9bDFzV7XlWs1w
Amit Gupta10y ago
Hi Niyazi
You can chekout thebelow link
https://msdn.microsoft.com/en-us/library/system.security.cryptography.aesmanaged(v=vs.110).aspx
Niyazi Toros10y ago
Hi,
Cannot open the page!!!
https://msdn.microsoft.com/en-us/library/system.security.cryptography.aesmanaged(v%3Dvs.110).aspx&ei=8594XmK5&lc=en-IN&s=1&m=738&host=www.google.co.in&ts=1463515960&sig=APY536zasIHpWnQx84t0m9bDFzV7XlWs1w
doesnt work...
Amit Gupta10y ago
Hi Niyazi If you want your output to be a fixed length of 16 characters , you can use String encrypwd=cl29dncwdlvj3pdmwdc)==¥÷; String output =encrypwd.SubString (0,16); However you can use padding as an when required
Niyazi Toros10y ago
Hi Amit,
Thank you for post. To understand your answer I have few question below?
1) If my string is say already a 16 character:
String password = 1234567890123456; I shouldn’t use PadLeft. Am I right?
2) If my string is say less than a 16 character:
String password = 12345; I should use PadLeft as you post it. String fixedpwd = password.PadLeft (16, '#'); Am I right?
3) From both usage, can I get the output encrypted string as 16 character?
My problem is whatever I use PadLeft or not I need my output to be a 16 character.
If my String password is 16 character I need my output 16 character as well.
· String password = 1234567890123456;
· String EncryptedPassword = ab89ergh234fhy8s;
Or
· String password = 12345 ;
· String EncryptedPassword = jkl34i67jgad6aw3;
Kind Regards