- Add stateful firewall functionality for UDP/TCP/ICMP in userspace firewalll
- Removes all egress drop rules/filters, still needs refactoring so we don't add output rules to any chains/filters.
- on Linux, if the OUTPUT policy is DROP then we don't do anything about it (no extra allow rules). This is up to the user, if they don't want anything leaving their machine they'll have to manage these rules explicitly.
This specifically concerns the established/related rule since this one is not compatible with iptables-nft even if it is generated the same way by iptables-translate.
- Update nftables library to v0.2.0
- Mark traffic that was originally destined for local and applies the input rules in the forward chain if said traffic was redirected (e.g. by Docker)
- Add nft rules to internal map only if flush was successful
- Improve error message if handle is 0 (= not found or hasn't been refreshed)
- Add debug logging when route rules are added
- Replace nftables userdata (rule ID) with a rule hash
* Add gocritic linter
`gocritic` provides diagnostics that check for bugs, performance, and style issues
We disable the following checks:
- commentFormatting
- captLocal
- deprecatedComment
This PR contains many `//nolint:gocritic` to disable `appendAssign`.
Add a default firewall rule to allow netbird traffic to be handled
by the access control managers.
Userspace manager behavior:
- When running on Windows, a default rule is add on Windows firewall
- For Linux, we are using one of the Kernel managers to add a single rule
- This PR doesn't handle macOS
Kernel manager behavior:
- For NFtables, if there is a filter table, an INPUT rule is added
- Iptables follows the previous flow if running on kernel mode. If running
on userspace mode, it adds a single rule for INPUT and OUTPUT chains
A new checkerFW package has been introduced to consolidate checks across
route and access control managers.
It supports a new environment variable to skip nftables and allow iptables tests
* Optimize rules with All groups
* Use IP sets in ACLs (nftables implementation)
* Fix squash rule when we receive optimized rules list from management
* Extend protocol and firewall manager to handle old management
* Send correct empty firewall rules list when delete peer
* Add extra tests for firewall manager and uspfilter
* Work with inconsistent state
* Review note
* Update comment
