lgcosta
131672d6ce
kernel-config.sh looked for the tree two levels up and build-kernel.sh did not pass on the tree it had resolved, so a plain ./scripts/build-kernel.sh could configure one tree and build another. Both resolve <repo>/../linux-7.3.4.
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, hfsc.c, … ported from OpenBSD 8.0 sources) driven by
the real OpenBSD pfctl over the /dev/pf ioctl ABI.
Status: the filter core, stateful filtering, tables, anchors, NAT
(nat-to/rdr-to/binat-to), forced routing (route-to/dup-to/reply-to),
pools, divert, pflog and the OpenBSD 8.0 queues (HFSC) are verified
in a real libvirt lab — 15/15 gates green. What is still pending is stated
per feature in docs/en/feature-matrix.md.
Screencasts (EN + PT, narrated): docs/en/screencast.md.
Design: docs/superpowers/specs/2026-11-11-pf-linux-port-design.md
· plan: docs/superpowers/plans/2026-11-11-pf-linux-port.md.
Milestones
| Milestone | Scope | Status |
|---|---|---|
| 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 |
done — gates 05/06/07/09 (incl. 2 MB integrity through a redirect, min-ttl/max-mss measured) |
| M4 | route-to/dup-to/reply-to, pools, divert e2e, pflog | done — divert (11), pflog (12), route-to/dup-to (08), pools (10), reply-to (13) verified |
| M5 | queues: HFSC back end in the data path | done (mechanical) — gate 15: queues load, hfsc attaches, pfctl -s queue -v reports class stats, a 2 MB queued flow is counted by the class. bandwidth = HFSC linkshare (guarantee, not cap; 8.0 has no upperlimit syntax) |
| M6 | docs complete, patchset tidy, full suite green, tagged release | done — docs EN+PT-BR, 15/15 suite green, tagged (v1.0.0) |
What you get
| 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: HFSC verified in the data path (gate 15), priq default, FQ-CoDel compiled; pfctl -s queue -v works |
| 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/reply-to + pools (round-robin, source-hash) verified (fail-to no longer exists in OpenBSD 8.0) |
| 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).
Screencasts
Seven narrated screencasts per language (English and Portuguese), 1080p30 with burned-in subtitles, the lab's network diagram drawn over the terminal, and a continuous film that crossfades the phases together. Every video is a real shell session against the Alpine VMs — commands typed key by key, the kernel answering live — with a MiniMax female voice narrating:
./scripts/screencast/build-all.sh # -> out/screencast/{en,pt}/*.mp4
Details, per-phase breakdown and the YouTube description text:
docs/en/screencast.md ·
docs/pt-BR/screencast.md
Quick start
Full recipe: docs/en/install.md. Short version
(commands are read from the scripts):
./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,pdivert,pflogd,abitest}
sudo insmod module/pf.ko # /dev/pf (0600) + netfilter hooks
sudo pfctl -f /etc/pf.conf && sudo pfctl -e
Every feature listed above is exercised by the lab suite before you need it;
docs/en/feature-matrix.md says which gate proves
what, and docs/en/pf-guide.md lists the deviations you
should know before putting PF on a path that matters.
VM validation lab (Alpine on libvirt): docs/en/vm-lab.md.
Documentação em português: README.pt-BR.md e
docs/pt-BR/.
Layout
module/— kernel sources: ported PF engine (module/pfsrc) + Linux compat layer (module/compat)tools/— pfctl (static Linux build), pdivert relay, pflogd, ABI harness (make -C tools abi)patches/kernel/— Linux core patch set (currently empty; evidence inp1-needs.txt, seedocs/en/patches.md)scripts/— fetch/build/patch/VM automation, plusscripts/screencast/for the videostests/vm/— VM suite: 15 gates (tests/vm/NN-*.sh) +lib.shdocs/en/+docs/pt-BR/— full bilingual documentationdocs/superpowers/— design spec + implementation plan
License
Ported OpenBSD code retains its original ISC license and copyright notices. New Linux-side code: ISC.