[Zlib-devel] Blowfish transparent encryptography in zlib

[mob]

Hi,
   I would like to use zlib in a commercial product using embedded linux.
I would like to use zlib + libtar + blowfish encryptography to do a
firmware loader in the product. For this purpose I would like to modify
zlib to support transparent blowfish encryptography. I have some doubts if
is it easy to do that as zlib must be modified to do reads and writes in
files respecting an eigth byte boundary (blowfish block size). 
   By this way it will be possible to extract a big encrypted and
compressed image file, writing the firmware upgrade in sysem flash memory.
The advantage of this method is that it does not need too much RAM system
memory, even for burning several Mbytes of flash memory (in the product
flash memory is much bigger than RAM).

thanks,
Moises Beck