Date
1 - 5 of 5
How to use DTLS with offloaded socket if the underlying modem does not support DTLS
Holger Gräf
Dear all, 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). Is there any easy way to implement this? Thanks and all the best, Holger
|
|
Holger,
Great if you have created a driver...you may want to create a PR so that it gets reviewed by the Dev community The man that should be able to help is Mike Scott. Billy..
|
|
A quick internet search brought up a manual which gave a basic DLTS example:
https://www.quectel.com/UploadImage/Downlad/Quectel_BC95-G&BC68_AT_Commands_Manual_V1.1.pdf BC95-G&BC68_AT_Commands_Manual -- Pg 122 Register to Huawei’s IoT Platform with DTLS
AT+CGATT? //Query the PS service attach status.
+CGATT:1 //Attached to the PS service.
OK
AT+NCDP= 180.101.147.115,5684 //Set IoT platform IP address and port. The port is 5684.
OK
AT+QSECSWT=1 //Encryption using standard DTLS.
OK
AT+QSETPSK=201703230000024,0123456789ABCDEF0123456789ABCDEF
OK //Set PSK ID and PSK.
AT+QREGSWT? //Query the registration mode.
+QREGSWT:0 //Manual registration mode.
OK
AT+QLWSREGIND=0 //Start to register to the IoT platform.
OK
+QLWEVTIND:0 //Successful registration indication.
|
|
Holger Gräf
Hi Billy,
thanks for the reply. I still have to clean up the driver a bit, then I will create the PR. With regard to the second message, thanks for the hint. I have already stumbled upon these commands, but according to the manual they are specific to Huawei's IoT platform, which I don't use. I have the impression that it's based on LwM2M, but I would like to be able to use DTLS encryption regardless of the protocol I use (UDP, TCP or the higher level COAPS or LwM2M). That's why I'm looking for a way to use Zephyr's mbedtls with my offloaded sockets. Any help would be very much appreciated :-) All the best, Holger
|
|
Jukka Rissanen
Hi Holger,
toggle quoted messageShow quoted text
one option is use the generic GSM modem, which uses PPP to connect to modem, instead of offloading the IP stack to the modem. In that case one can send DTLS data via the modem. Unfortunately the modem you mentioned (Quectel BC68) does not seem to support PPP mode. Cheers, Jukka
On Wed, 2020-02-26 at 02:04 -0800, Holger Gräf wrote:
Hi Billy,
|
|