Commit Graph

3 Commits

Author SHA1 Message Date
Wade Simmons 6e0ae4f9a3
firewall: add option to send REJECT replies (#738)
* firewall: add option to send REJECT replies

This change allows you to configure the firewall to send REJECT packets
when a packet is denied.

    firewall:
      # Action to take when a packet is not allowed by the firewall rules.
      # Can be one of:
      #   `drop` (default): silently drop the packet.
      #   `reject`: send a reject reply.
      #     - For TCP, this will be a RST "Connection Reset" packet.
      #     - For other protocols, this will be an ICMP port unreachable packet.
      outbound_action: drop
      inbound_action: drop

These packets are only sent to established tunnels, and only on the
overlay network (currently IPv4 only).

    $ ping -c1 192.168.100.3
    PING 192.168.100.3 (192.168.100.3) 56(84) bytes of data.
    From 192.168.100.3 icmp_seq=2 Destination Port Unreachable

    --- 192.168.100.3 ping statistics ---
    2 packets transmitted, 0 received, +1 errors, 100% packet loss, time 31ms

    $ nc -nzv 192.168.100.3 22
    (UNKNOWN) [192.168.100.3] 22 (?) : Connection refused

This change also modifies the smoke test to capture tcpdump pcaps from
both the inside and outside to inspect what is going on over the wire.
It also now does TCP and UDP packet tests using the Nmap version of
ncat.

* calculate seq and ack the same was as the kernel

The logic a bit confusing, so we copy it straight from how the kernel
does iptables `--reject-with tcp-reset`:

- https://github.com/torvalds/linux/blob/v5.19/net/ipv4/netfilter/nf_reject_ipv4.c#L193-L221

* cleanup
2023-03-13 15:08:40 -04:00
Wade Simmons 45d1d2b6c6
Update dependencies - 2022-04 (#664)
Updated  github.com/kardianos/service         https://github.com/kardianos/service/compare/v1.2.0...v1.2.1
    Updated  github.com/miekg/dns                 https://github.com/miekg/dns/compare/v1.1.43...v1.1.48
    Updated  github.com/prometheus/client_golang  https://github.com/prometheus/client_golang/compare/v1.11.0...v1.12.1
    Updated  github.com/prometheus/common         https://github.com/prometheus/common/compare/v0.32.1...v0.33.0
    Updated  github.com/stretchr/testify          https://github.com/stretchr/testify/compare/v1.7.0...v1.7.1
    Updated  golang.org/x/crypto                  5770296d90...ae2d96664a
    Updated  golang.org/x/net                     69e39bad7d...749bd193bc
    Updated  golang.org/x/sys                     7861aae155...289d7a0edf
    Updated  golang.zx2c4.com/wireguard/windows   v0.5.1...v0.5.3
    Updated  google.golang.org/protobuf           v1.27.1...v1.28.0
2022-04-18 12:12:25 -04:00
Nate Brown bcabcfdaca
Rework some things into packages (#489) 2021-11-03 20:54:04 -05:00