Searching through the source code of everything installed on my Gentoo system with rg 'socket([AP]F_ALG' /usr/src/debug found only 6 packages that use it: iproute2, util-linux, bluez, qtconnectivity, openssl, and ell. Out of these packages, only ell explicitly uses aead support in cipher.c . ell is depended on by bluez and iwd, and out of those two, iwd doesn't use aead support as none of the aead symbols are in the final binary. As far I know, the only thing that uses algif_aead is bluetooth-meshd .