I have adapted the Sara R4 modem driver (zephyr/drivers/modem/ublox-sara-r4.c) in Zephyr in order to control a Quectel BC68 NB-IoT modem. The aim is to use this with Zephyr's LwM2M engine. Without DTLS everything works fine.
Now I want to add DTLS encryption to my setup, but I have not managed to figure out how to implement this with the socket offload API used by the modem driver (note that the Quectel modem I use does not itself support DTLS sockets).
