maxvarm / ebpf-docker-lsm

Monitor and block specified processes and network connections with this docker-aware KRSI (BPF+LSM) security tool

Docker-aware KRSI (BPF+LSM) security monitoring and prevention tool

My attempt to connect eBPF LSM hooks with docker context like container ID, name, and image. The tool works by correlating cgroup inode available from the kernel part with docker container id available from user space. For now, it is possible to audit outbound IPv4 network connections via lsm/socket_connect hook and process creation via lsm/bprm_check_security hook.

Build

A modern, BTF and LSM-capable kernel is required to run the tool (5.7+ I suppose). From my observations, Ubuntu 22.04 does not yet enable LSM features by default, but I managed to run it Manjaro Linux without any kernel changes. To run the tool.

(BTF/LSM) One of these commands must return two "y":

zcat /proc/config.gz | grep -E 'CONFIG_DEBUG_INFO_BTF=|CONFIG_BPF_LSM='
cat /boot/config | grep -E 'CONFIG_DEBUG_INFO_BTF=|CONFIG_BPF_LSM='
cat /boot/config-$(uname -r) | grep -E 'CONFIG_DEBUG_INFO_BTF=|CONFIG_BPF_LSM='

(LSM hooks) One of these commands must have "bpf" flag:

zcat /proc/config.gz | grep CONFIG_LSM=
cat /boot/config | grep CONFIG_LSM=
cat /boot/config-$(uname -r) | grep CONFIG_LSM=

(Build) You must also install kernel headers, C compiler, and bpftool to build the tool from source. Then:

git clone --recurse-submodules https://github.com/maxvarm/ebpf-docker-lsm.git
cd ebpf-docker-lsm && make
sudo ./ebpf-docker

Examples

1. Run the tool as root

sudo ./ebpf-docker

2. Check DEMO_BLOCK_* macros in ebpf-docker.bpf.c
3. Run some commands to fit into DEMO_BLOCK_* condition
4. Check the error and appropriate events in ebpf-docker.log

Block a specific process only for a specific image:

Block outbound connections to 4444 port from host and containers:

Check how it appears in logs (ebpf-docker.log):