Commit Graph

20 Commits (593c0868667400e89d2179c5c311bbc03adc6c86)

Author SHA1 Message Date
Maisem Ali c3a8e63100 util/linuxfw: add additional nftable detection logic
We were previously using the netlink API to see if there are chains/rules that
already exist. This works fine in environments where there is either full
nftable support or no support at all. However, we have identified certain
environments which have partial nftable support and the only feasible way of
detecting such an environment is to try to create some of the chains that we
need.

This adds a check to create a dummy postrouting chain which is immediately
deleted. The goal of the check is to ensure we are able to use nftables and
that it won't error out later. This check is only done in the path where we
detected that the system has no preexisting nftable rules.

Updates #5621
Updates #8555
Updates #8762

Signed-off-by: Maisem Ali <maisem@tailscale.com>
1 year ago
Maisem Ali b47cf04624 util/linuxfw: fix broken tests
These tests were broken at HEAD. CI currently does not run these
as root, will figure out how to do that in a followup.

Updates #5621
Updates #8555
Updates #8762

Signed-off-by: Maisem Ali <maisem@tailscale.com>
1 year ago
Maisem Ali fbfee6a8c0 cmd/containerboot: use linuxfw.NetfilterRunner
This migrates containerboot to reuse the NetfilterRunner used
by tailscaled instead of manipulating iptables rule itself.
This has the added advantage of now working with nftables and
we can potentially drop the `iptables` command from the container
image in the future.

Updates #9310

Co-authored-by: Irbe Krumina <irbe@tailscale.com>
Signed-off-by: Maisem Ali <maisem@tailscale.com>
1 year ago
Maisem Ali aad3584319 util/linuxfw: move fake runner into pkg
This allows using the fake runner in different packages
that need to manage filter rules.

Updates #cleanup

Signed-off-by: Maisem Ali <maisem@tailscale.com>
1 year ago
Maisem Ali 05a1f5bf71 util/linuxfw: move detection logic
Just a refactor to consolidate the firewall detection logic in a single
package so that it can be reused in a later commit by containerboot.

Updates #9310

Signed-off-by: Maisem Ali <maisem@tailscale.com>
1 year ago
James Tucker ba6ec42f6d util/linuxfw: add missing input rule to the tailscale tun
Add an explicit accept rule for input to the tun interface, as a mirror
to the explicit rule to accept output from the tun interface.

The rule matches any packet in to our tun interface and accepts it, and
the rule is positioned and prioritized such that it should be evaluated
prior to conventional ufw/iptables/nft rules.

Updates #391
Fixes #7332
Updates #9084

Signed-off-by: James Tucker <james@tailscale.com>
1 year ago
James Tucker 2066f9fbb2 util/linuxfw: fix crash in DelSNATRule when no rules are found
Appears to be a missing nil handling case. I looked back over other
usage of findRule and the others all have nil guards. findRule returns
nil when no rules are found matching the arguments.

Fixes #9553
Signed-off-by: James Tucker <james@tailscale.com>
1 year ago
Craig Rodrigues 8452d273e3 util/linuxfw: Fix comment which lists supported linux arches
Only arm64 and amd64 are supported

Signed-off-by: Craig Rodrigues <rodrigc@crodrigues.org>
1 year ago
Craig Rodrigues 8683ce78c2 client/web, clientupdate, util/linuxfw, wgengine/magicsock: Use %v verb for errors
Replace %w verb with %v verb when logging errors.
Use %w only for wrapping errors with fmt.Errorf()

Fixes: #9213

Signed-off-by: Craig Rodrigues <rodrigc@crodrigues.org>
1 year ago
Brad Fitzpatrick 1b223566dd util/linuxfw: fix typo in unexported doc comment
And flesh it out and use idiomatic doc style ("whether" for bools)
and end in a period while there anyway.

Updates #cleanup

Change-Id: Ieb82f13969656e2340c3510e7b102dc8e6932611
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
1 year ago
KevinLiang10 b040094b90 util/linuxfw: reorganize nftables rules to allow it to work with ufw
This commit tries to mimic the way iptables-nft work with the filewall rules. We
follow the convention of using tables like filter, nat and the conventional
chains, to make our nftables implementation work with ufw.

Updates: #391

Signed-off-by: KevinLiang10 <kevinliang@tailscale.com>
1 year ago
Brad Fitzpatrick 7a5263e6d0 util/linuxfw: rename ErrorFWModeNotSupported
Go style is for error variables to start with "err" (or "Err")
and for error types to end in "Error".

Updates #cleanup

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
1 year ago
KevinLiang10 ae63c51ff1 wgengine/router: add auto selection heuristic for iptables/nftables
This commit replaces the TS_DEBUG_USE_NETLINK_NFTABLES envknob with
a TS_DEBUG_FIREWALL_MODE that should be set to either 'iptables' or
'nftables' to select firewall mode manually, other wise tailscaled
will automatically choose between iptables and nftables depending on
environment and system availability.

updates: #319
Signed-off-by: KevinLiang10 <kevinliang@tailscale.com>
1 year ago
Brad Fitzpatrick 88cc0ad9f7 util/linuxfw: remove yet-unused code to fix linux/arm64 crash
The util/linuxfw/iptables.go had a bunch of code that wasn't yet used
(in prep for future work) but because of its imports, ended up
initializing code deep within gvisor that panicked on init on arm64
systems not using 4KB pages.

This deletes the unused code to delete the imports and remove the
panic. We can then cherry-pick this back to the branch and restore it
later in a different way.

A new test makes sure we don't regress in the future by depending on
the panicking package in question.

Fixes #8658

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
1 year ago
KevinLiang10 a3c7b21cd1 util/linuxfw: add nftables support
This commit adds nftable rule injection for tailscaled. If tailscaled is
started with envknob TS_DEBUG_USE_NETLINK_NFTABLES = true, the router
will use nftables to manage firewall rules.

Updates: #391

Signed-off-by: KevinLiang10 <kevinliang@tailscale.com>
1 year ago
KevinLiang10 6ebd87c669 util/linuxfw: add new arch build constraints
Exclide GOARCHs including: mips, mips64, mips64le, mipsle, riscv64.
These archs are not supported by gvisor.dev/gvisor/pkg/hostarch.

Fixes: #391
Signed-off-by: KevinLiang10 <kevinliang@tailscale.com>
1 year ago
KevinLiang10 243ce6ccc1 util/linuxfw: decoupling IPTables logic from linux router
This change is introducing new netfilterRunner interface and moving iptables manipulation to a lower leveled iptables runner.

For #391

Signed-off-by: KevinLiang10 <kevinliang@tailscale.com>
1 year ago
Brad Fitzpatrick eefee6f149 all: use cmpx.Or where it made sense
I left a few out where writing it explicitly was better
for various reasons.

Updates #8296

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
1 year ago
Andrew Dunham 6927a844b1 util/linuxfw: add build constraints excluding GOARCH=arm
This isn't currently supported due to missing support in upstream
dependencies, and also we don't use this package anywhere right now.
Just conditionally skip this for now.

Fixes #7268

Change-Id: Ie7389c2c0816b39b410c02a7276051a4c18b6450
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
2 years ago
Andrew Dunham ba48ec5e39 util/linuxfw: initial implementation of package
This package is an initial implementation of something that can read
netfilter and iptables rules from the Linux kernel without needing to
shell out to an external utility; it speaks directly to the kernel using
syscalls and parses the data returned.

Currently this is read-only since it only knows how to parse a subset of
the available data.

Signed-off-by: Andrew Dunham <andrew@tailscale.com>
Change-Id: Iccadf5dcc081b73268d8ccf8884c24eb6a6f1ff5
2 years ago