Hi,
first, this is probably not the apprpriate forum for
general cryptographic help (unless of course you
are looking for a security consulting to come help
you, in which case you can look at my personal website
and retain my services ;)
Having said that....
Mauricio Junqueira <mau(_dot_)go(_at_)terra(_dot_)com(_dot_)br> writes:
.. a cipher text encoded in CFB mode could be decrypted in CBC ?
No. CFB and CBC are completely different crypto modes.
[snip]
But it only operates on 16bytes each time, what makes it
a CBC mode ( I guess ).
No. It has a 16-byte block size, but that does not make it CBC.
My solution was to complete with spaces the remain bytes to have
an entire block, but what about the IV?
You should read Applied Cryptography. This is "not the way". There
are a number of standard padding techniques, but you do not need
them if you use CFB mode. CFB mode always gives you the "exact"
amount of ciphertext that you need.
I will lose some quality if I drop the IV and CFB mode in the
server or is there a way to use the IV in CBC mode like pre-pending
the IV or using all zeros IV in CFB...
This question does not make sense.
I hope I have found the right place to post this and I was encouraged
in doing so after reading some messages from this mail list.
Not really, as this list is for discussion of the OpenPGP
specification, not about cryptography in general.
Thank you for your time in reading this and
who knows if some one could enlightenment me
in the right direction.
As I said, I recommend you read Applied Cryptograhy, or
engage the services of a Security Consultant to help you
understand all the issues...
Good Luck,
Mauricio Junqueira
mau(_dot_)go(_at_)terra(_dot_)com(_dot_)br
-derek
--
Derek Atkins 617-623-3745
derek(_at_)ihtfp(_dot_)com www.ihtfp.com
Computer and Internet Security Consultant