Commit Graph

38 Commits (219efebad4a0867f9de486e43d57046ea7b72e92)

Author SHA1 Message Date
Anton Tolchanov 8cc5c51888 health: warn about reverse path filtering and exit nodes
When reverse path filtering is in strict mode on Linux, using an exit
node blocks all network connectivity. This change adds a warning about
this to `tailscale status` and the logs.

Example in `tailscale status`:

```
- not connected to home DERP region 22
- The following issues on your machine will likely make usage of exit nodes impossible: [interface "eth0" has strict reverse-path filtering enabled], please set rp_filter=2 instead of rp_filter=1; see https://github.com/tailscale/tailscale/issues/3310
```

Example in the logs:
```
2024/02/21 21:17:07 health("overall"): error: multiple errors:
	not in map poll
	The following issues on your machine will likely make usage of exit nodes impossible: [interface "eth0" has strict reverse-path filtering enabled], please set rp_filter=2 instead of rp_filter=1; see https://github.com/tailscale/tailscale/issues/3310
```

Updates #3310

Signed-off-by: Anton Tolchanov <anton@tailscale.com>
9 months ago
Andrew Dunham 727acf96a6 net/netcheck: use DERP frames as a signal for home region liveness
This uses the fact that we've received a frame from a given DERP region
within a certain time as a signal that the region is stil present (and
thus can still be a node's PreferredDERP / home region) even if we don't
get a STUN response from that region during a netcheck.

This should help avoid DERP flaps that occur due to losing STUN probes
while still having a valid and active TCP connection to the DERP server.

RELNOTE=Reduce home DERP flapping when there's still an active connection

Updates #8603

Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: If7da6312581e1d434d5c0811697319c621e187a0
11 months ago
Brad Fitzpatrick 4d196c12d9 health: don't report a warning in DERP homeless mode
Updates #3363
Updates tailscale/corp#396

Change-Id: Ibfb0496821cb58a78399feb88d4206d81e95ca0f
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
12 months ago
Brad Fitzpatrick dc7aa98b76 all: use set.Set consistently instead of map[T]struct{}
I didn't clean up the more idiomatic map[T]bool with true values, at
least yet.  I just converted the relatively awkward struct{}-valued
maps.

Updates #cleanup

Change-Id: I758abebd2bb1f64bc7a9d0f25c32298f4679c14f
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
1 year ago
Brad Fitzpatrick 14320290c3 control/controlclient: merge, simplify two health check calls
I'm trying to remove some stuff from the netmap update path.

Updates #1909

Change-Id: Iad2c728dda160cd52f33ef9cf0b75b4940e0ce64
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
1 year ago
Andrew Dunham 2755f3843c health, net/tlsdial: add healthcheck for self-signed cert
When we make a connection to a server, we previously would verify with
the system roots, and then fall back to verifying with our baked-in
Let's Encrypt root if the system root cert verification failed.

We now explicitly check for, and log a health error on, self-signed
certificates. Additionally, we now always verify against our baked-in
Let's Encrypt root certificate and log an error if that isn't
successful. We don't consider this a health failure, since if we ever
change our server certificate issuer in the future older non-updated
versions of Tailscale will no longer be healthy despite being able to
connect.

Updates #3198

Change-Id: I00be5ceb8afee544ee795e3c7a2815476abc4abf
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
2 years ago
Will Norris 71029cea2d all: update copyright and license headers
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>
2 years ago
Tom DNetto 0088c5ddc0 health,ipn/ipnlocal: report the node being locked out as a health issue
Signed-off-by: Tom DNetto <tom@tailscale.com>
2 years ago
Aaron Klotz 659e7837c6 health, ipn/ipnlocal: when -no-logs-no-support is enabled, deny access to tailnets that have network logging enabled
We want users to have the freedom to start tailscaled with `-no-logs-no-support`,
but that is obviously in direct conflict with tailnets that have network logging
enabled.

When we detect that condition, we record the issue in health, notify the client,
set WantRunning=false, and bail.

We clear the item in health when a profile switch occurs, since it is a
per-tailnet condition that should not propagate across profiles.

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2 years ago
Brad Fitzpatrick ea25ef8236 util/set: add new set package for SetHandle type
We use this pattern in a number of places (in this repo and elsewhere)
and I was about to add a fourth to this repo which was crossing the line.
Add this type instead so they're all the same.

Also, we have another Set type (SliceSet, which tracks its keys in
order) in another repo we can move to this package later.

Change-Id: Ibbdcdba5443fae9b6956f63990bdb9e9443cefa9
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 3f8e185003 health: add Warnable, move ownership of warnable items to callers
The health package was turning into a rando dumping ground. Make a new
Warnable type instead that callers can request an instance of, and
then Set it locally in their code without the health package being
aware of all the things that are warnable. (For plenty of things the
health package will want to know details of how Tailscale works so it
can better prioritize/suppress errors, but lots of the warnings are
pretty leaf-y and unrelated)

This just moves two of the health warnings. Can probably move more
later.

Change-Id: I51e50e46eb633f4e96ced503d3b18a1891de1452
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick e55ae53169 tailcfg: add Node.UnsignedPeerAPIOnly to let server mark node as peerapi-only
capver 48

Change-Id: I20b2fa81d61ef8cc8a84e5f2afeefb68832bd904
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 3562b5bdfa envknob, health: support Synology, show parse errors in status
Updates #5114

Change-Id: I8ac7a22a511f5a7d0dcb8cac470d4a403aa8c817
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 74674b110d envknob: support changing envknobs post-init
Updates #5114

Change-Id: Ia423fc7486e1b3f3180a26308278be0086fae49b
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Jordan Whited 43f9c25fd2
cmd/tailscale: surface authentication errors in status.Health (#4748)
Fixes #3713

Signed-off-by: Jordan Whited <jordan@tailscale.com>
2 years ago
Brad Fitzpatrick 2ff481ff10 net/dns: add health check for particular broken-ish Linux DNS config
Updates #3937 (need to write docs before closing)

Change-Id: I1df7244cfbb0303481e2621ee750d21358bd67c6
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 41fd4eab5c envknob: add new package for all the strconv.ParseBool(os.Getenv(..))
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>
3 years ago
Brad Fitzpatrick 0aa4c6f147 net/dns/resolver: add debug HTML handler to see what DNS traffic was forwarded
Change-Id: I6b790e92dcc608515ac8b178f2271adc9fd98f78
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 8f43ddf1a2 ipn/ipnlocal, health: populate self node's Online bit in tailscale status
One option was to just hide "offline" in the text output, but that
doesn't fix the JSON output.

The next option was to lie and say it's online in the JSON (which then
fixes the "offline" in the text output).

But instead, this sets the self node's "Online" to whether we're in an
active map poll.

Fixes #3564

Change-Id: I9b379989bd14655198959e37eec39bb570fb814a
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
David Anderson 6c82cebe57 health: add a health state for net/dns.OSConfigurator.
Lets the systemd-resolved OSConfigurator report health changes
for out of band config resyncs.

Updates #3327

Signed-off-by: David Anderson <danderson@tailscale.com>
3 years ago
Josh Bleecher Snyder 3fd5f4380f util/multierr: new package
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>
3 years ago
Brad Fitzpatrick 09e692e318 health: don't look for UDP goroutines in js/wasm health check
Updates #3157

Change-Id: I43d97e6876eeb2d1936fc567835134568bb8615c
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick aae622314e tailcfg, health: add way for control plane to add problems to health check
So if the control plane knows that something's broken about the node, it can
include problem(s) in MapResponse and "tailscale status" will show it.
(and GUIs in the future, as it's in ipnstate.Status/JSON)

This also bumps the MapRequest.Version, though it's not strictly
required. Doesn't hurt.

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 4549d3151c cmd/tailscale: make status show health check problems
Fixes #2775

RELNOTE=tailscale status now shows health check problems

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 5bacbf3744 wgengine/magicsock, health, ipn/ipnstate: track DERP-advertised health
And add health check errors to ipnstate.Status (tailscale status --json).

Updates #2746
Updates #2775

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Josh Bleecher Snyder 9d542e08e2 wgengine/magicsock: always run ReceiveIPv6
One of the consequences of the 	bind refactoring in 6f23087175
is that attempting to bind an IPv6 socket will always
result in c.pconn6.pconn being non-nil.
If the bind fails, it'll be set to a placeholder packet conn
that blocks forever.

As a result, we can always run ReceiveIPv6 and health check it.
This removes IPv4/IPv6 asymmetry and also will allow health checks
to detect any IPv6 receive func failures.

Signed-off-by: Josh Bleecher Snyder <josharian@gmail.com>
4 years ago
Josh Bleecher Snyder fe50ded95c health: track whether we have a functional udp4 bind
Suggested-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Signed-off-by: Josh Bleecher Snyder <josharian@gmail.com>
4 years ago
Josh Bleecher Snyder 744de615f1 health, wgenegine: fix receive func health checks for the fourth time
The old implementation knew too much about how wireguard-go worked.
As a result, it missed genuine problems that occurred due to unrelated bugs.

This fourth attempt to fix the health checks takes a black box approach.
A receive func is healthy if one (or both) of these conditions holds:

* It is currently running and blocked.
* It has been executed recently.

The second condition is required because receive functions
are not continuously executing. wireguard-go calls them and then
processes their results before calling them again.

There is a theoretical false positive if wireguard-go go takes
longer than one minute to process the results of a receive func execution.
If that happens, we have other problems.

Updates #1790

Signed-off-by: Josh Bleecher Snyder <josharian@gmail.com>
4 years ago
Josh Bleecher Snyder 0d4c8cb2e1 health: delete ReceiveFunc health checks
They were not doing their job.
They need yet another conceptual re-think.
Start by clearing the decks.

Signed-off-by: Josh Bleecher Snyder <josharian@gmail.com>
4 years ago
Josh Bleecher Snyder 8d7f7fc7ce health, wgenegine: fix receive func health checks yet again
The existing implementation was completely, embarrassingly conceptually broken.

We aren't able to see whether wireguard-go's receive function goroutines
are running or not. All we can do is model that based on what we have done.
This commit fixes that model.

Fixes #1781

Signed-off-by: Josh Bleecher Snyder <josharian@gmail.com>
4 years ago
Josh Bleecher Snyder 5835a3f553 health, wgengine/magicsock: avoid receive function false positives
Avery reported a sub-ms health transition from "receiveIPv4 not running" to "ok".

To avoid these transient false-positives, be more precise about
the expected lifetime of receive funcs. The problematic case is one in which
they were started but exited prior to a call to connBind.Close.
Explicitly represent started vs running state, taking care with the order of updates.

Signed-off-by: Josh Bleecher Snyder <josharian@gmail.com>
4 years ago
Josh Bleecher Snyder f845aae761 health: track whether magicsock receive functions are running
Signed-off-by: Josh Bleecher Snyder <josharian@gmail.com>
4 years ago
David Anderson f007a9dd6b health: add DNS subsystem and plumb errors in.
Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
Brad Fitzpatrick 85138d3183 health: track whether any network interface is up
Fixes #1562

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
4 years ago
Brad Fitzpatrick 9eb65601ef health, ipn/ipnlocal: track, log overall health
Updates #1505

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
4 years ago
Brad Fitzpatrick 232cfda280 wgengine/router: report to control when setPrivateNetwork fails
Fixes #1503

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
4 years ago
Brad Fitzpatrick ba8c6d0775 health, controlclient, ipn, magicsock: tell health package state of things
Not yet checking anything. Just plumbing states into the health package.

Updates #1505

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
4 years ago
Brad Fitzpatrick fd8e070d01 health, control/controlclient, wgengine: report when router unhealthy
Updates tailscale/corp#1338

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
4 years ago