Why does openssl still pad data for aes-128-cbc encrypting when the file-size%16==0?

[Nicle]

Hi all,

I can understand if file-size%16 != 0, openssl will pad data.

But it will also pad 16bytes for those file size exactly 16 times.

For example: original file size 16 bytes, cipher file size: 32 bytes.

Any help will be so appreciated.

Best Regards
Neo