f4gw

F4GW

Prerequisites

kernel >= v5.10

TOPO

Client[192.168.226.21] <--> F4GW[192.168.226.22, 192.168.127.22] <--> F4Proxy[192.168.127.31] <--> Internet

TEST

Client

curl http://httpbin.org -I

nslookup httpbin.org 8.8.8.8

ping 8.8.8.8

clear;tcpdump -i ens33 -en host 3.213.1.197

F4GW

system=$(uname -s | tr [:upper:] [:lower:])
arch=$(dpkg --print-architecture)
release=v0.4.1-alpha.1
curl -L https://github.com/cybwan/f4gw/releases/download/${release}/f4gw-${release}-${system}-${arch}.tar.gz | tar -vxzf -
cd ./${system}-${arch}

# modify gw.json
./f4gw -c gw.json

F4Proxy

system=$(uname -s | tr [:upper:] [:lower:])
arch=$(dpkg --print-architecture)
release=v0.4.1-alpha.1
curl -L https://github.com/cybwan/f4gw/releases/download/${release}/f4gw-${release}-${system}-${arch}.tar.gz | tar -vxzf -
cd ./${system}-${arch}

# modify proxy.json
./f4proxy -c proxy.json

# new terminal
pipy proxy.js

Tracing log (now disabled)

sudo cat /sys/kernel/debug/tracing/trace_pipe|grep bpf_trace_printk

nat netflow messages:

     ksoftirqd/0-14      [000] d.s21  7171.643922: bpf_trace_printk: ==================================
     ksoftirqd/0-14      [000] d.s21  7171.643949: bpf_trace_printk: f4m proto 17        ipv6(?) 0
     ksoftirqd/0-14      [000] d.s21  7171.643951: bpf_trace_printk: f4m daddr 8.8.8.8 dport 53
     ksoftirqd/0-14      [000] d.s21  7171.643953: bpf_trace_printk: f4m saddr 192.168.226.21 sport 39508
     ksoftirqd/0-14      [000] d.s21  7171.643953: bpf_trace_printk: f4m xaddr 192.168.127.22 xport 39508
          <idle>-0       [000] d.s31  7172.345965: bpf_trace_printk: ==================================
          <idle>-0       [000] dNs31  7172.345994: bpf_trace_printk: f4m proto 6         ipv6(?) 0
          <idle>-0       [000] dNs31  7172.345996: bpf_trace_printk: f4m daddr 18.208.239.112 dport 80
          <idle>-0       [000] dNs31  7172.345997: bpf_trace_printk: f4m saddr 192.168.226.21 sport 34706
          <idle>-0       [000] dNs31  7172.345997: bpf_trace_printk: f4m xaddr 192.168.127.22 xport 34706

Nat Netflow

bpftool map dump name f4gw_nat_opts