This busybox fwmaskWorks check was added before we moved away from
using the "ip" command to using netlink directly.
So it's now just wasted work (and log spam on Gokrazy) to check the
"ip" command capabilities if we're never going to use it.
Do it lazily instead.
Updates #12277
Change-Id: I8ab9acf64f9c0d8240ce068cb9ec8c0f6b1ecee7
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
After some analysis, stateful filtering is only necessary in tailnets
that use `autogroup:danger-all` in `src` in ACLs. And in those cases
users explicitly specify that hosts outside of the tailnet should be
able to reach their nodes. To fix local DNS breakage in containers, we
disable stateful filtering by default.
Updates #12108
Signed-off-by: Andrew Lytvynov <awly@tailscale.com>
When Docker is detected on the host and stateful filtering is enabled,
Docker containers may be unable to reach Tailscale nodes (depending on
the network settings of a container). Detect Docker when stateful
filtering is enabled and print a health warning to aid users in noticing
this issue.
We avoid printing the warning if the current node isn't advertising any
subnet routes and isn't an exit node, since without one of those being
true, the node wouldn't have the correct AllowedIPs in WireGuard to
allow a Docker container to connect to another Tailscale node anyway.
Updates #12070
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: Idef538695f4d101b0ef6f3fb398c0eaafc3ae281
Trying to run iptables/nftables on Synology pauses for minutes with
lots of errors and ultimately does nothing as it's not used and we
lack permissions.
This fixes a regression from db760d0bac (#11601) that landed
between Synology testing on unstable 1.63.110 and 1.64.0 being cut.
Fixes#11737
Change-Id: Iaf9563363b8e45319a9b6fe94c8d5ffaecc9ccef
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
This removes a potentially increased boot delay for certain boot
topologies where they block on ExecStartPre that may have socket
activation dependencies on other system services (such as
systemd-resolved and NetworkManager).
Also rename cleanup to clean up in affected/immediately nearby places
per code review commentary.
Fixes#11599
Signed-off-by: James Tucker <james@tailscale.com>
Only on Gokrazy, set sysctls to enable IP forwarding so subnet routing
and advertised exit node works.
Fixes#11405
Signed-off-by: Joonas Kuorilehto <joneskoo@derbian.fi>
We have hosts that support IPv6, but not IPv6 firewall configuration
in iptables mode.
We also have hosts that have some support for IPv6 firewall
configuration in iptables mode, but do not have iptables filter table.
We should:
- configure ip rules for all hosts that support IPv6
- only configure firewall rules in iptables mode if the host
has iptables filter table.
Updates tailscale/tailscale#11540
Signed-off-by: Irbe Krumina <irbe@tailscale.com>
Run `staticcheck` with `U1000` to find unused code. This cleans up about
a half of it. I'll do the other half separately to keep PRs manageable.
Updates #cleanup
Signed-off-by: Andrew Lytvynov <awly@tailscale.com>
* util/linuxfw, wgengine: allow ingress to magicsock UDP port on Linux
Updates #9084.
Currently, we have to tell users to manually open UDP ports on Linux when
certain firewalls (like ufw) are enabled. This change automates the process of
adding and updating those firewall rules as magicsock changes what port it
listens on.
Signed-off-by: Naman Sood <mail@nsood.in>
This will enable the runner to be replaced as a configuration side
effect in a later change.
Updates tailscale/corp#14029
Signed-off-by: James Tucker <james@tailscale.com>
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>
Due to the conflict between our nftables implementation and ufw, which is a common utility used
on linux. We now want to take a step back to prevent regression. This will give us more chance to
let users to test our nftables support and heuristic.
Updates: #391
Signed-off-by: KevinLiang10 <kevinliang@tailscale.com>
To record wether user is using iptables or nftables after we add support to nftables on linux, we
are adding a field FirewallMode to NetInfo in HostInfo to reflect what firewall mode the host is
running, and form metrics. The information is gained from a global constant in hostinfo.go. We
set it when selection heuristic made the decision, and magicsock reports this to control.
Updates: tailscale/corp#13943
Signed-off-by: KevinLiang10 <kevinliang@tailscale.com>
The current router errors out when neither iptables nor nftables support is present. We
should fall back to the previous behaviour which we creates a dummy iptablesRunner.
Fixes: #8878
Signed-off-by: KevinLiang10 <kevinliang@tailscale.com>
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>
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>
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>
We're using it in more and more places, and it's not really specific to
our use of Wireguard (and does more just link/interface monitoring).
Also removes the separate interface we had for it in sockstats -- it's
a small enough package (we already pull in all of its dependencies
via other paths) that it's not worth the extra complexity.
Updates #7621
Updates #7850
Signed-off-by: Mihai Parparita <mihai@tailscale.com>
WSL has started to set the eth0 default route interface default to 1280
MTU, which is too low to carry 1280 byte packets from tailscale0 once
wrapped in WireGuard. The change down to 1280 is very likely smaller
than necessary for almost all users. We can not easily determine the
ideal MTU, but if all the preconditions match, we raise the MTU to 1360,
which is just enough for Tailscale traffic to work.
Updates #4833
Updates #7346
Signed-off-by: James Tucker <james@tailscale.com>
This updates all source files to use a new standard header for copyright
and license declaration. Notably, copyright no longer includes a date,
and we now use the standard SPDX-License-Identifier header.
This commit was done almost entirely mechanically with perl, and then
some minimal manual fixes.
Updates #6865
Signed-off-by: Will Norris <will@tailscale.com>
This is temporary while we work to upstream performance work in
https://github.com/WireGuard/wireguard-go/pull/64. A replace directive
is less ideal as it breaks dependent code without duplication of the
directive.
Signed-off-by: Jordan Whited <jordan@tailscale.com>
Deleting may temporarily result in no addrs on the interface, which results in
all other rules (like routes) to get dropped by the OS.
I verified this fixes the problem.
Signed-off-by: Maisem Ali <maisem@tailscale.com>
Context: https://github.com/tailscale/tailscale/pull/5588#issuecomment-1260655929
It seems that if the interface at index 1 is down, the rule is not installed. As such,
we increase the range we detect up to 2004 in the hope that at least one of the interfaces
1-4 will be up.
Signed-off-by: Tom DNetto <tom@tailscale.com>
The io/ioutil package has been deprecated as of Go 1.16 [1]. This commit
replaces the existing io/ioutil functions with their new definitions in
io and os packages.
Reference: https://golang.org/doc/go1.16#ioutil
Signed-off-by: Eng Zer Jun <engzerjun@gmail.com>
This change masks the bitspace used when setting and querying the fwmark on packets. This allows
tailscaled to play nicer with other networking software on the host, assuming the other networking
software is also using fwmarks & a different mask.
IPTables / mark module has always supported masks, so this is safe on the netfilter front.
However, busybox only gained support for parsing + setting masks in 1.33.0, so we make sure we
arent such a version before we add the "/<mask>" syntax to an ip rule command.
Signed-off-by: Tom DNetto <tom@tailscale.com>
This reverts commit 8d6793fd70.
Reason: breaks Android build (cgo/pthreads addition)
We can try again next cycle.
Change-Id: I5e7e1730a8bf399a8acfce546a6d22e11fb835d5
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Attempt to load the xt_mark kernel module when it is not present. If the
load fails, log error information.
It may be tempting to promote this failure to an error once it has been
in use for some time, so as to avoid reaching an error with the iptables
invocation, however, there are conditions under which the two stages may
disagree - this change adds more useful breadcrumbs.
Example new output from tailscaled running under my WSL2:
```
router: ensure module xt_mark: "/usr/sbin/modprobe xt_mark" failed: exit status 1; modprobe: FATAL: Module xt_mark not found in directory /lib/modules/5.10.43.3-microsoft-standard-WSL2
```
Background:
There are two places to lookup modules, one is `/proc/modules` "old",
the other is `/sys/module/` "new".
There was query_modules(2) in linux <2.6, alas, it is gone.
In a docker container in the default configuration, you would get
/proc/modules and /sys/module/ both populated. lsmod may work file,
modprobe will fail with EPERM at `finit_module()` for an unpriviliged
container.
In a priviliged container the load may *succeed*, if some conditions are
met. This condition should be avoided, but the code landing in this
change does not attempt to avoid this scenario as it is both difficult
to detect, and has a very uncertain impact.
In an nspawn container `/proc/modules` is populated, but `/sys/module`
does not exist. Modern `lsmod` versions will fail to gather most module
information, without sysfs being populated with module information.
In WSL2 modules are likely missing, as the in-use kernel typically is
not provided by the distribution filesystem, and WSL does not mount in a
module filesystem of its own. Notably the WSL2 kernel supports iptables
marks without listing the xt_mark module in /sys/module, and
/proc/modules is empty.
On a recent kernel, we can ask the capabilities system about SYS_MODULE,
that will help to disambiguate between the non-privileged container case
and just being root. On older kernels these calls may fail.
Update #4329
Signed-off-by: James Tucker <james@tailscale.com>
This was just cleanup for an ancient version of Tailscale. Any such machines
have upgraded since then.
Change-Id: Iadcde05b37c2b867f92e02ec5d2b18bf2b8f653a
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
A new package can also later record/report which knobs are checked and
set. It also makes the code cleaner & easier to grep for env knobs.
Change-Id: Id8a123ab7539f1fadbd27e0cbeac79c2e4f09751
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Tailscale 1.18 uses netlink instead of the "ip" command to program the
Linux kernel.
The old way was kept primarily for tests, but this also adds a
TS_DEBUG_USE_IP_COMMAND environment knob to force the old way
temporarily for debugging anybody who might have problems with the
new way in 1.18.
Updates #391
Change-Id: I0236fbfda6c9c05dcb3554fcc27ec0c86456efd9
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
github.com/go-multierror/multierror served us well.
But we need a few feature from it (implement Is),
and it's not worth maintaining a fork of such a small module.
Instead, I did a clean room implementation inspired by its API.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
