GPGME question about ciphertext and plaintext sizes

Dim Xr dimxrss at
Tue May 9 16:48:31 CEST 2023

Hello all,
I'm currently working on a userspace block device driver. I want to add
encryption on it,
and that's how I came across GPGME.

My question is: is there a way to encrypt a plaintext and get a ciphertext
of **exactly** the
same size? Is there any way to have FPE (Format Preserving Encryption) via

>From my research so far, it doesn't seem to exist one. Even symmetric
algorithms are using
metadata on the ciphertext so the size is always bigger than the
corresponding plaintext.

All suggestions are welcome!

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