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7 commits

Author SHA1 Message Date
Rasmus Moorats
ff28230b75
use uname -m instead of the arch command
The `arch` command is deprecated on modern systems, and indeed,
many distros do not provide it (one of those being Arch Linux,
ironically). Since `uname` is already used in the Makefile, prefer
its `-m` flag equivalent instead.
2023-06-12 16:01:18 +03:00
Gustavo Iñiguez Goia
72646221c3
ebpf: switched to CO:RE compilation
- don't require kernel headers to build the module:
  https://nakryiko.com/posts/bpf-portability-and-co-re/#getting-rid-of-kernel-header-dependency
- use CO:RE BTF file:
  https://nakryiko.com/posts/bpf-portability-and-co-re/#btf
2023-06-10 18:12:26 +02:00
Gustavo Iñiguez Goia
63e996d7bb
ebpf: new way of compiling the modules
- Don't rename libbpf's bpf_map_def struct, and distribute the needed bpf
  headers.
  The bpf_map_def struct has been deprecated for quite some time now,
  and it was been removed on >= 6.2 anyway.
  We still need it, because we use gobpf.
- Improved compilation behaviour:
  - We don't require the kernel sources anymore. We can just use the
    kernel headers from the distribution.
  - There's no need to copy the sources to the kernel tree, the modules
    can be compiled from the ebpf_prog/ dir.
- Compiling against kernels 6.x seems to solve the problem we had with
  VPNs, where connections were not intercepted with modules compiled
  against 5.8, on kernels >= 5.19.

The modules has been tested on kernels 4.17, 5.4, 5.10, 5.15, 6.1 and
6.2 (kernel connections included).
2023-06-07 01:23:01 +02:00
Gustavo Iñiguez Goia
0526b84309
Allow to intercept more kernel connections (#513)
* Allow to intercept some kernel connections

Some connections are initiated from kernel space, like WireGuard
VPNs (#454), NFS or SMB connections (#502) and ip tunnels (#500).

Note: This feature is complete for x86_64, WIP for aarch64, and not supported for armhf and i386
https://github.com/evilsocket/opensnitch/pull/513#issuecomment-924400824

More information regarding this change: #493
2021-09-23 01:44:12 +02:00
Gustavo Iñiguez Goia
c66d5d6bf0 ebpf: updated dependencies list for compiling 2021-09-13 11:49:27 +02:00
Gustavo Iñiguez Goia
05f7e38f9d ebpf: added patch to compile ebpf module for arm 2021-04-21 20:49:31 +02:00
themighty1
9497cf8394
Use ebpf program to find PID of new connections. (#397)
* Use ebpf program to find PID of new connections.

    before running the branch you have to compile ebpf_prog/opensnitch.c
    opensnitch.c is an eBPF program. Compilation requires getting kernel source.

    cd opensnitch
    wget https://github.com/torvalds/linux/archive/v5.8.tar.gz
    tar -xf v5.8.tar.gz
    patch linux-5.8/tools/lib/bpf/bpf_helpers.h < ebpf_prog/file.patch
    cp ebpf_prog/opensnitch.c ebpf_prog/Makefile linux-5.8/samples/bpf
    cd linux-5.8 && yes "" | make oldconfig && make prepare && make headers_install # (1 min)
    cd samples/bpf && make
    objdump -h opensnitch.o #you should see many section, number 1 should be called kprobe/tcp_v4_connect
    llvm-strip -g opensnitch.o #remove debug info
    sudo cp opensnitch.o /etc/opensnitchd
    cd ../../../daemon

    --opensnitchd expects to find opensnitch.o in /etc/opensnitchd/
    --start opensnitchd with:

    opensnitchd -rules-path /etc/opensnitchd/rules -process-monitor-method ebpf

Co-authored-by: themighty1 <you@example.com>
Co-authored-by: Gustavo Iñiguez Goia <gooffy1@gmail.com>
2021-04-05 11:28:16 +02:00