Passthrough Marvell mv_cesa crypto device into LXC container

howto

#1

Since I couldn’t find any documentation within the web, and others might be interested in this as well: below are the steps that are required to get the mv_cesa crypto device also running within a LXC container:

  1. check for the device number of the crypto device within the host:

$ ls -lh /dev/crypto
crw-rw-rw- 1 root root 10, 58 Sep 9 04:37 /dev/crypto

  1. add the following with the appropriate device numbers to the LXC config:

lxc.cgroup.devices.allow = c 10:58 rwm
lxc.mount.entry=/dev/crypto dev/crypto none bind

  1. start and attach to the LXC container with the example name LXCNAME:

$ lxc-start -n LXCNAME
$ lxc-attach -n LXCNAME

  1. install the cryptodev variant of the openssl package within the LXC container, e.g. ArchLinux ARM:

$ pacman -S openssl-cryptodev

  1. double check if CESA is not available yet:

$ openssl engine
(dynamic) Dynamic engine loading support

  1. create device within the LXC container:

$ mknod -m 666 /dev/crypto c 10 58

  1. recheck if CESA is available now:

$ openssl engine
(cryptodev) BSD cryptodev engine
(dynamic) Dynamic engine loading support

  1. Well, one would like to make the crypto dev sticky. There are two solutions, one clean one and the hack. Clean: the host creates it; hack: systemd within the LXC container creates it. Let’s go for the clean approach. First shutdown the LXC container, which will automatically bring the console back to the host:

$ shutdown -h now

  1. within the host create a hook-dev.sh bash file:

$ touch /srv/lxc/LXCNAME/hook-dev.sh

  1. fill the hook-dev.sh bash file with:

#!/bin/sh
mknod -m 666 ${LXC_ROOTFS_MOUNT}/dev/crypto c 10 58

  1. make it executable:

chmod +x /srv/lxc/LXCNAME/hook-dev.sh

  1. and add the following to the LXC config:

lxc.autodev = 1
lxc.hook.autodev = /srv/lxc/LXCNAME/hook-dev.sh

  1. restart the LXC container again and check if crypto device exists.

$ lxc-start -n LXCNAME
$ lxc-attach -n LXCNAME
$ ls -lh /dev/crypto

Performance difference of OpenSSL running in a LXC container on Turris Omnia (LXC: ArchLinux ARM, OpenSSL 1.1.0f 25 May 2017):

without CESA:

openssl speed -elapsed
type 16 bytes 64 bytes 256 bytes 1024 bytes 8192 bytes 16384 bytes
aes-128 cbc 52244.84k 56235.95k 57947.65k 58386.77k 58485.42k 58512.73k
aes-192 cbc 45435.00k 48243.46k 49410.82k 49787.90k 49886.55k 49949.35k
aes-256 cbc 40156.08k 42207.68k 43060.57k 43287.55k 43409.41k 43401.22k

openssl speed -elapsed -evp
type 16 bytes 64 bytes 256 bytes 1024 bytes 8192 bytes 16384 bytes
aes-128-cbc 45071.30k 54032.15k 57328.55k 58189.82k 58482.69k 58250.58k
aes-192-cbc 39709.57k 46521.62k 48943.36k 49591.64k 49793.71k 49790.98k
aes-256-cbc 35532.03k 40856.53k 42719.83k 43228.84k 43141.80k 43275.61k

with CESA (implicit):

openssl speed -elapsed
type 16 bytes 64 bytes 256 bytes 1024 bytes 8192 bytes 16384 bytes
aes-128 cbc 52273.96k 56370.39k 57992.36k 58381.65k 58488.15k 58376.19k
aes-192 cbc 45454.22k 48287.32k 49451.09k 49746.26k 49815.55k 49829.21k
aes-256 cbc 40128.84k 42223.34k 43119.79k 43339.43k 43423.06k 43357.53k

openssl speed -elapsed -evp
type 16 bytes 64 bytes 256 bytes 1024 bytes 8192 bytes 16384 bytes
aes-128-cbc 932.09k 3736.49k 10498.40k 34319.70k 87375.87k 95114.58k
aes-192-cbc 937.24k 3734.06k 10391.81k 33792.00k 83580.25k 91630.25k
aes-256-cbc 933.85k 3736.28k 10356.48k 33200.13k 80584.70k 87233.88k

with CESA (explicit):

openssl speed -elapsed -engine cryptodev
type 16 bytes 64 bytes 256 bytes 1024 bytes 8192 bytes 16384 bytes
aes-128 cbc 52359.45k 56383.15k 57976.49k 58405.55k 58518.19k 58359.81k
aes-192 cbc 45462.99k 48312.41k 49441.62k 49732.61k 49831.94k 49856.51k
aes-256 cbc 40145.91k 42265.07k 43119.96k 43331.58k 43376.64k 43461.29k

openssl speed -elapsed -engine cryptodev -evp
type 16 bytes 64 bytes 256 bytes 1024 bytes 8192 bytes 16384 bytes
aes-128-cbc 928.81k 3707.54k 10409.73k 34230.27k 87075.50k 95262.04k
aes-192-cbc 934.06k 3733.74k 10384.90k 33594.03k 82944.00k 90576.21k
aes-256-cbc 931.14k 3701.72k 10309.55k 33102.17k 80557.40k 87457.79k

Similar approach, but on bare metal Turris Omnia not tackling LXC containers has been pursued here: https://forum.turris.cz/t/hw-crypto-marvell-cesa-working/1276


HW crypto - Marvell CESA working?
closed #2