Comparing The Encryption Speed of GPG vs OpenSSL

Encrypting data at rest is a modern requirement that occurs all the time. The go-to method that most admins think of is to use GPG.

But it’s slow.

How slow? Lets find out.

First, I generated a 1GB file of random data:

dd if=/dev/urandom of=data.file bs=1MB count=1024

Then I timed its encryption with GPG:

gpg --encrypt --compress-level 0 --sign --armor -r data.file
Time:    0m13.285s

The --compress-level 0 disables compression as there is no compression used by OpenSSL.

Next, I tried the same with OpenSSL:

openssl enc -aes-256-cbc -salt -in data.file -out data.file.enc
Time:    0m3.199s

That’s better than a 4x improvement!

Finally, decrypt the OpenSSL encrypted file with the following:

openssl enc -aes-256-cbc -d -in data.file.enc -out data.file