Re: GPGME question about ciphertext and plaintext sizes

2023-05-15 Thread Werner Koch via Gnupg-users
On Wed, 10 May 2023 14:43, Dim Xr said: > I'm far from a security expert, that's why I needed a more > higher level solution for this. But definitely I'll give it a shot. Use DMCrypt under Linux or Veracrypt etc. Disk encryption is a complicated matter and you definitley should have some experi

Re: GPGME question about ciphertext and plaintext sizes

2023-05-10 Thread Dim Xr via Gnupg-users
Thank you Werner. You need to use a low level crypto library > for that (e.g. Libgcrypt) and decide which algorithm, mode and > additional information you use. > OK I'll check it out. Searching on the mailing list responses I came across with Libgcrypt again, but I've read that it is quite low-le

Re: GPGME question about ciphertext and plaintext sizes

2023-05-10 Thread Werner Koch via Gnupg-users
On Tue, 9 May 2023 17:48, Dim Xr said: > same size? Is there any way to have FPE (Format Preserving Encryption) via > GPGME? No. GPGME uses the OpenPGP and S/MIME protocols (gpg and gpgsm) and is not suitable for your task. You need to use a low level crypto library for that (e.g. Libgcrypt) a

GPGME question about ciphertext and plaintext sizes

2023-05-09 Thread Dim Xr via Gnupg-users
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 Encrypti