87 lines
4.8 KiB
Markdown
87 lines
4.8 KiB
Markdown
# PF on Linux
|
||
|
||
Port of the OpenBSD **PF** (packet filter) to **Linux 7.3.4** as an
|
||
out-of-tree kernel module — the real PF engine (`pf.c`, `pf_norm.c`,
|
||
`pf_table.c`, `pf_lb.c`, … ported from OpenBSD 8.0 sources) driven by the
|
||
real OpenBSD `pfctl` over the `/dev/pf` ioctl ABI. (A second module for the
|
||
`pfq` qdisc arrives with M5.)
|
||
|
||
**Status:** the filter core, stateful filtering, tables, anchors, NAT
|
||
(`nat-to`/`rdr-to`/`binat-to`), forced routing (`route-to`/`dup-to`), `divert`
|
||
and `pflog` are **verified in a real libvirt lab** (11/11 gates green). The
|
||
remaining features (scrub e2e, ALTQ/pfq, af-to, `fail-to`/`reply-to`) are
|
||
still pending — honest per-feature status:
|
||
[`docs/en/feature-matrix.md`](docs/en/feature-matrix.md).
|
||
Demo (asciinema): [`docs/en/demo.md`](docs/en/demo.md).
|
||
Design: [`docs/superpowers/specs/2026-11-11-pf-linux-port-design.md`](docs/superpowers/specs/2026-11-11-pf-linux-port-design.md)
|
||
· plan: [`docs/superpowers/plans/2026-11-11-pf-linux-port.md`](docs/superpowers/plans/2026-11-11-pf-linux-port.md).
|
||
|
||
## Milestones
|
||
|
||
| Milestone | Scope | Status (2026-11-11) |
|
||
|---|---|---|
|
||
| M0 | repo, scripts, kernel build, VM boots the custom kernel | done |
|
||
| M1 | compat layer, `pf.ko` loads, `/dev/pf`, `pfctl -f` / `-s info` | done |
|
||
| M2 | filter core: rules/states/tables/anchors, VM gates 01–04 | **done** — gates 01/02/03/04 green |
|
||
| M3 | NAT (`nat-to`/`rdr-to`/`binat-to`), scrub e2e | **partial** — NAT verified (gate 05), redirect incl. 2 MB integrity (gate 06), `binat-to` (gate 07); scrub e2e pending |
|
||
| M4 | route-to/dup-to/fail-to, divert e2e, pflog | **partial** — divert (gate 11), pflog (gate 12), route-to/dup-to (gate 08) verified; `fail-to`/`reply-to` pending |
|
||
| M5 | queues: HFSC/FQ-CoDel back ends + `pfq` qdisc | pending |
|
||
| M6 | docs complete, patchset tidy, full suite green, tagged release | **done** — docs EN+PT-BR, 11/11 suite green, tagged (v0.5.0) |
|
||
|
||
## What you get (planned)
|
||
|
||
| Area | Feature |
|
||
|---|---|
|
||
| Filtering | rules, anchors, quick, `match`/`block`(drop/return/return-rst)/`pass`, `keep state`, syncookies |
|
||
| State/Tables | stateful firewall engine, `pfr` tables (radix + hash, `pfctl -t`) |
|
||
| NAT | `nat-to` (port pools, sticky-port, static-port), `rdr-to`, `binat-to` |
|
||
| Scrub | fragment reassembly, overlap drop, `min-ttl`/`max-mss`/`df`/`no-df`, `set reassemble` |
|
||
| QoS (ALTQ successor) | `queue`/`queue on` with OpenBSD 8.0 `ifq` schedulers: **default (priq), HFSC, FQ-CoDel**, attached via the `pfq` qdisc; `pfctl -s queue -v` stats |
|
||
| Divert | `divert-to` / `divert` tag + `pdivert` relay over an in-module `PF_DIVERT` socket family (verified: packet to userspace and back) |
|
||
| Route | `route-to`/`dup-to` verified; pools (`rr`, `source-hash`), `fail-to`, `reply-to` pending |
|
||
| Logging | `pflogd` via `/dev/pflog` (DLT_PFLOG pcap, OpenBSD record layout) — verified |
|
||
| Control | `/dev/pf` (0600), OpenBSD 8.0 ioctl ABI, Linux build of `pfctl` (single binary) |
|
||
|
||
Not in scope: `pfsync`/CARP failover, IPsec/pfkey, `ftp-proxy`, per-netns PF
|
||
instances, classic-ALTQ-only schedulers (cbq/wfq/red — removed upstream before
|
||
OpenBSD 8.0).
|
||
|
||
## Quick start
|
||
|
||
Full recipe: [`docs/en/install.md`](docs/en/install.md). Short version
|
||
(commands are read from the scripts; a fresh-clone end-to-end run is still
|
||
pending):
|
||
|
||
```sh
|
||
./scripts/fetch-sources.sh # OpenBSD 8.0 sources (C3SL mirror, sha256-pinned)
|
||
./scripts/vendorize.sh # stage the pristine files we port
|
||
./scripts/build-kernel.sh # kernel 7.3.4: bzImage + modules_prepare (export patch: none needed)
|
||
./scripts/build-module.sh # -> module/pf.ko
|
||
make -C tools # -> tools/out/pfctl (static), ABI harness
|
||
sudo insmod module/pf.ko # /dev/pf (0600) + netfilter hooks
|
||
sudo pfctl -f /etc/pf.conf && sudo pfctl -e
|
||
```
|
||
|
||
Read [`docs/en/pf-guide.md`](docs/en/pf-guide.md) **before** enabling PF on a
|
||
path you need: only the M2 filter core is gated today; NAT/scrub/queues/
|
||
divert/pflog are not usable yet ([`docs/en/feature-matrix.md`](docs/en/feature-matrix.md)).
|
||
|
||
VM validation lab (Alpine on libvirt): [`docs/en/vm-lab.md`](docs/en/vm-lab.md).
|
||
Documentação em português: [`README.pt-BR.md`](README.pt-BR.md) e
|
||
[`docs/pt-BR/`](docs/pt-BR/README.md).
|
||
|
||
## Layout
|
||
|
||
- `module/` — kernel sources (ported PF + compat layer; the `pfq` qdisc lands with M5)
|
||
- `tools/` — pfctl (static Linux build), pdivert relay source, ABI harness (`pflogd` not ported yet)
|
||
- `patches/kernel/` — Linux core patch set (currently empty; evidence in `p1-needs.txt`, see `docs/en/patches.md`)
|
||
- `scripts/` — fetch/build/patch/VM automation
|
||
- `tests/` — VM suite (`tests/vm/NN-*.sh`, scapy helpers)
|
||
- `docs/en/` + `docs/pt-BR/` — full bilingual documentation
|
||
- `docs/superpowers/` — design spec + implementation plan
|
||
|
||
## License
|
||
|
||
Ported OpenBSD code retains its original [ISC license and copyright notices](LICENSE).
|
||
New Linux-side code: ISC.
|