Padding issue with C++ Crypto RC2 encryption

From: kishore (kishore_at_discussions.microsoft.com)
Date: 01/26/05 

Date: Wed, 26 Jan 2005 10:45:07 -0800

Hello, I'm using the Crypto API RC2 encryption under Visual Studio 6 C++.

I've written some code and got encryption and decryption working fine.

The problem is when data is encrypted, the data is padded to accommodate for
block size. So I have the data encrypted with these additional characters.
The problem then is when I decrypt it, I get back the decrypted data with
the additional characters. My question(s) are :

1. How can I prevent the additional characters being padded and encrypted?
Is this even possible?

2. If I can't prevent #1 above, how can I extract only the encrypted
substring associated with the original string. If my original string was
"hello", I tried extracting only 5 chars from the encrypted string so I could
use this for decryption to get back "hello", but this didn't work.

Is there a one to one correspondence between the length of a string and the
lenght of an encrypted string? E.g. If have the string "hello" and have it
encrypted, will each letter in "hello" be associated with a single character
in the encrypted string?

Thanks.

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