SYD-AES(1) General Commands Manual SYD-AES(1)

syd-aes - AES-CTR encryption and decryption utility

syd-aes [-hv] -e|-d -k <key-serial> -i <iv-hex>

syd-aes utility encrypts and decrypts data using AES-256-CTR in userspace, selecting the encryption/decryption key from the keyrings(7) interface by its serial ID. It supports both encryption and decryption operations, with key serial provided as a 32-bit ID and IV provided as a hexadecimal string. Given data from stdin(3), syd-aes performs the specified operation and outputs the result to stdout(3), and is able to encrypt/decrypt files of arbitrary size.

-h Display help.
-v Enable verbose mode.
If stderr(2) is a terminal, print progress updates periodically, similar to dd(1).
-e Encrypt input data.
-d Decrypt input data.
-k <key-serial> Key serial ID (32-bit integer).
Key must grant read permission to syd-aes, otherwise operation is denied.
Use syd-key(1) to generate a key with required permission.
-i <iv> Hex-encoded IV (128 bits).

syd(1), syd(2), syd(5), syd-key(1), keyrings(7)

syd homepage: https://sydbox.exherbo.org/

Maintained by Ali Polatel. Up-to-date sources can be found at https://gitlab.exherbo.org/sydbox/sydbox.git and on Radicle at rad:z38HCnbmcDegA2BMxuPaPRPMdp6wF. Bugs/patches can be submitted to https://gitlab.exherbo.org/groups/sydbox/-/issues. Discuss in #sydbox on Libera Chat or in #sydbox:mailstation.de on Matrix.

2026-07-12