Talk:Enc

Rarely Used -K option

"This is rarely used, normally you specify a password from which a key is derived."

Is this true? Does it not depend fairly heavily on your use case? Just not sure what the basis for this statement is.

--Matt 21:39, 27 June 2013 (UTC)

Probably you are right. Its a biased statement. I'll change it.

--Frukto 07:27, 28 June 2013 (UTC)

Zlib compression

"Use this flag to enable zlib-compression. After a file is encrypted (and maybe base64 encoded) it will be compressed via zlib. Vice versa while decrypting, zlib will be applied first."

I think this happens the other way around. Doesn't compression occur before encryption, or after decryption? It doesn't make sense to do it the other way around - after encryption the data will appear indistinguishable from random data, and therefore should not have any appreciable ability to be compressed.

--Matt 12:17, 5 July 2013 (UTC)

Yes, i had the same question. But i tried it and it works actually like this: encryption -> base64 -> zlib

encrypt + unzip:

$ openssl enc -des -in message.plain -a -out message.enc -nosalt -z $ printf "\x1f\x8b\x08\x00\x00\x00\x00\x00" |cat - message.enc | gzip -dc

gives the same as:

$ openssl enc -des -in message.plain -a -out message.enc -nosalt

--Frukto 14:05, 5 July 2013 (UTC)