187 Commits

Author SHA1 Message Date
Claus Lensbøl
b816fd7117
control/controlclient: introduce eventbus messages instead of callbacks (#16956)
This is a small introduction of the eventbus into controlclient that
communicates with mainly ipnlocal. While ipnlocal is a complicated part
of the codebase, the subscribers here are from the perspective of
ipnlocal already called async.

Updates #15160

Signed-off-by: Claus Lensbøl <claus@tailscale.com>
2025-09-15 10:36:17 -04:00
Brad Fitzpatrick
b034f7cca9 ipn/ipnlocal, util/syspolicy: convert last RegisterWellKnownSettingsForTest caller, remove
Updates #16998

Change-Id: I735d75129a97a929092e9075107e41cdade18944
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2025-09-04 12:45:44 -07:00
Brad Fitzpatrick
d06d9007a6 ipn/ipnlocal: convert more tests to use policytest, de-global-ify
Now that we have policytest and the policyclient.Client interface, we
can de-global-ify many of the tests, letting them run concurrently
with each other, and just removing global variable complexity.

This does ~half of the LocalBackend ones.

Updates #16998

Change-Id: Iece754e1ef4e49744ccd967fa83629d0dca6f66a
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2025-09-02 21:46:25 -07:00
Brad Fitzpatrick
24b8a57b1e util/syspolicy/policytest: move policy test helper to its own package
Updates #16998
Updates #12614

Change-Id: I9fd27d653ebee547951705dc5597481e85b60747
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2025-09-02 17:03:26 -07:00
M. J. Fromberger
9e9bf13063
ipn/ipnlocal: revert some locking changes ahead of release branch cut (#17011) 2025-09-02 15:57:31 -07:00
Brad Fitzpatrick
0d23490e1a ipn/ipnlocal: simplify a test with a new simpler syspolicy client test type
Less indirection.

Updates #16998
Updates #12614

Change-Id: I5a3a3c3f3b195486b2731ec002d2532337b3d211
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2025-09-02 10:28:35 -07:00
Brad Fitzpatrick
1ca4ae598a ipn/ipnlocal: use policyclient.Client always, stop using global syspolicy funcs
Step 4 of N. See earlier commits in the series (via the issue) for the
plan.

This adds the missing methods to policyclient.Client and then uses it
everywhere in ipn/ipnlocal and locks it in with a new dep test.

Still plenty of users of the global syspolicy elsewhere in the tree,
but this is a lot of them.

Updates #16998
Updates #12614

Change-Id: I25b136539ae1eedbcba80124de842970db0ca314
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2025-09-02 10:28:35 -07:00
Brad Fitzpatrick
cc532efc20 util/syspolicy/*: move syspolicy keys to new const leaf "pkey" package
This is step 1 of ~3, breaking up #14720 into reviewable chunks, with
the aim to make syspolicy be a build-time configurable feature.

In this first (very noisy) step, all the syspolicy string key
constants move to a new constant-only (code-free) package. This will
make future steps more reviewable, without this movement noise.

There are no code or behavior changes here.

The future steps of this series can be seen in #14720: removing global
funcs from syspolicy resolution and using an interface that's plumbed
around instead. Then adding build tags.

Updates #12614

Change-Id: If73bf2c28b9c9b1a408fe868b0b6a25b03eeabd1
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2025-08-31 17:09:24 -07:00
M. J. Fromberger
6c8fef961e
ipn/ipnlocal: replace the LockedOnEntry pattern with conventional lock/unlock discipline (#16925)
There are several methods within the LocalBackend that used an unusual and
error-prone lock discipline whereby they require the caller to hold the backend
mutex on entry, but release it on the way out.

In #11650 we added some support code to make this pattern more visible.
Now it is time to eliminate the pattern (at least within this package).
This is intended to produce no semantic changes, though I am relying on
integration tests and careful inspection to achieve that.

To the extent possible I preserved the existing control flow. In a few places,
however, I replaced this with an unlock/lock closure. This means we will
sometimes reacquire a lock only to release it again one frame up the stack, but
these operations are not performance sensitive and the legibility gain seems
worthwhile.

We can probably also pull some of these out into separate methods, but I did
not do that here so as to avoid other variable scope changes that might be hard
to see. I would like to do some more cleanup separately.

As a follow-up, we could also remove the unlockOnce helper, but I did not do
that here either.

Updates #11649

Change-Id: I4c92d4536eca629cfcd6187528381c33f4d64e20
Signed-off-by: M. J. Fromberger <fromberger@tailscale.com>
2025-08-23 02:07:22 -07:00
Michael Ben-Ami
3f1851a6d9 types/dnstype, ipn/ipnlocal: allow other DNS resolvers with exit nodes
dnstype.Resolver adds a boolean UseWithExitNode that controls
whether the resolver should be used in tailscale exit node contexts
(not wireguard exit nodes). If UseWithExitNode resolvers are found,
they are installed as the global resolvers. If no UseWithExitNode resolvers
are found, the exit node resolver continues to be installed as the global
resolver. Split DNS Routes referencing UseWithExitNode resolvers are also
installed.

Updates #8237

Fixes tailscale/corp#30906
Fixes tailscale/corp#30907

Signed-off-by: Michael Ben-Ami <mzb@tailscale.com>
2025-08-15 08:17:01 -04:00
M. J. Fromberger
b34cdc9710
ipn,net,tsnet,wgengine: make an eventbus mandatory where it is used (#16594)
In the components where an event bus is already plumbed through, remove the
exceptions that allow it to be omitted, and update all the tests that relied on
those workarounds execute properly.

This change applies only to the places where we're already using the bus; it
does not enforce the existence of a bus in other components (yet),

Updates #15160

Change-Id: Iebb92243caba82b5eb420c49fc3e089a77454f65
Signed-off-by: M. J. Fromberger <fromberger@tailscale.com>
2025-07-29 09:04:08 -07:00
James Sanderson
5731869565 health: add an ETag to UnhealthyState for change detection
Updates tailscale/corp#30596

Signed-off-by: James Sanderson <jsanderson@tailscale.com>
2025-07-28 11:50:18 +01:00
Simon Law
1ef8fbf470
ipn/ipnlocal: send Hostinfo after resolveExitNode for "auto:any" (#16632)
In #16625, I introduced a mechanism for sending the selected exit node
to Control via tailcfg.Hostinfo.ExitNodeID as part of the MapRequest.
@nickkhyl pointed out that LocalBackend.doSetHostinfoFilterServices
needs to be triggered in order to actually send this update. This
patch adds that command. It also prevents the client from sending
"auto:any" in that field, because that’s not a real exit node ID.

This patch also fills in some missing checks in TestConfigureExitNode.

Updates tailscale/corp#30536

Signed-off-by: Simon Law <sfllaw@tailscale.com>
2025-07-23 11:50:42 -07:00
Simon Law
729d6532ff
tailcfg: add Hostinfo.ExitNodeID to report the selected exit node (#16625)
When a client selects a particular exit node, Control may use that as
a signal for deciding other routes.

This patch causes the client to report whenever the current exit node
changes, through tailcfg.Hostinfo.ExitNodeID. It relies on a properly
set ipn.Prefs.ExitNodeID, which should already be resolved by
`tailscale set`.

Updates tailscale/corp#30536

Signed-off-by: Simon Law <sfllaw@tailscale.com>
2025-07-22 13:54:28 -07:00
Simon Law
e84e58c567 ipn/ipnlocal: use rendezvous hashing to traffic-steer exit nodes
With auto exit nodes enabled, the client picks exit nodes from the
ones advertised in the network map. Usually, it picks the one with the
highest priority score, but when the top spot is tied, it used to pick
randomly. Then, once it made a selection, it would strongly prefer to
stick with that exit node. It wouldn’t even consider another exit node
unless the client was shutdown or the exit node went offline. This is
to prevent flapping, where a client constantly chooses a different
random exit node.

The major problem with this algorithm is that new exit nodes don’t get
selected as often as they should. In fact, they wouldn’t even move
over if a higher scoring exit node appeared.

Let’s say that you have an exit node and it’s overloaded. So you spin
up a new exit node, right beside your existing one, in the hopes that
the traffic will be split across them. But since the client had this
strong affinity, they stick with the exit node they know and love.

Using rendezvous hashing, we can have different clients spread
their selections equally across their top scoring exit nodes. When an
exit node shuts down, its clients will spread themselves evenly to
their other equal options. When an exit node starts, a proportional
number of clients will migrate to their new best option.

Read more: https://en.wikipedia.org/wiki/Rendezvous_hashing

The trade-off is that starting up a new exit node may cause some
clients to move over, interrupting their existing network connections.
So this change is only enabled for tailnets with `traffic-steering`
enabled.

Updates tailscale/corp#29966
Fixes #16551

Signed-off-by: Simon Law <sfllaw@tailscale.com>
2025-07-16 12:54:49 -07:00
Simon Law
c18ba4470b
ipn/ipnlocal: add traffic steering support to exit-node suggestions (#16527)
When `tailscale exit-node suggest` contacts the LocalAPI for a
suggested exit node, the client consults its netmap for peers that
contain the `suggest-exit-node` peercap. It currently uses a series of
heuristics to determine the exit node to suggest.

When the `traffic-steering` feature flag is enabled on its tailnet,
the client will defer to Control’s priority scores for a particular
peer. These scores, in `tailcfg.Hostinfo.Location.Priority`, were
historically only used for Mullvad exit nodes, but they have now been
extended to score any peer that could host a redundant resource.

Client capability version 119 is the earliest client that understands
these traffic steering scores. Control tells the client to switch to
rely on these scores by adding `tailcfg.NodeAttrTrafficSteering` to
its `AllCaps`.

Updates tailscale/corp#29966

Signed-off-by: Simon Law <sfllaw@tailscale.com>
2025-07-10 22:15:55 -07:00
Nick Khyl
ff1803158a ipn/ipnlocal: change order of exit node refresh and netmap update so that clients receive the new netmap first
If the GUI receives a new exit node ID before the new netmap, it may treat the node as offline or invalid
if the previous netmap didn't include the peer at all, or if the peer was offline or not advertised as an exit node.
This may result in briefly issuing and dismissing a warning, or a similar issue, which isn't ideal.

In this PR, we change the operation order to send the new netmap to clients first before selecting the new exit node
and notifying them of the Exit Node change.

Updates tailscale/corp#30252 (an old issue discovered during testing this)

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2025-07-09 13:45:33 -05:00
Nick Khyl
21a4058ec7 ipn/ipnlocal: add test to verify handling of unknown auto exit node expressions
We already check this for cases where ipn.Prefs.AutoExitNode is configured via syspolicy.
Configuring it directly through EditPrefs should behave the same, so we add a test for that as well.

Additionally, we clarify the implementation and future extensibility in (*LocalBackend).resolveAutoExitNodeLocked,
where the AutoExitNode is actually enforced.

Updates tailscale/corp#29969
Updates #cleanup

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2025-07-09 12:48:12 -05:00
Nick Khyl
cc2f4ac921 ipn: move ParseAutoExitNodeID from ipn/ipnlocal to ipn
So it can be used from the CLI without importing ipnlocal.

While there, also remove isAutoExitNodeID, a wrapper around parseAutoExitNodeID
that's no longer used.

Updates tailscale/corp#29969
Updates #cleanup

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2025-07-09 12:48:12 -05:00
Nick Khyl
740b77df59 ipn/ipnlocal,util/syspolicy: add support for ExitNode.AllowOverride policy setting
When the policy setting is enabled, it allows users to override the exit node enforced by the ExitNodeID
or ExitNodeIP policy. It's primarily intended for use when ExitNodeID is set to auto:any, but it can also
be used with specific exit nodes. It does not allow disabling exit node usage entirely.

Once the exit node policy is overridden, it will not be enforced again until the policy changes,
the user connects or disconnects Tailscale, switches profiles, or disables the override.

Updates tailscale/corp#29969

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2025-07-08 17:17:47 -05:00
Nick Khyl
2c630e126b ipn/ipnlocal: make applySysPolicy a method on LocalBackend
Now that applySysPolicy is only called by (*LocalBackend).reconcilePrefsLocked,
we can make it a method to avoid passing state via parameters and to support
future extensibility.

Also factor out exit node-specific logic into applyExitNodeSysPolicyLocked.

Updates tailscale/corp#29969

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2025-07-08 16:06:40 -05:00
Nick Khyl
f1c7b463cd ipn/{ipnauth,ipnlocal,localapi}: make EditPrefs return an error if changing exit node is restricted by policy
We extract checkEditPrefsAccessLocked, adjustEditPrefsLocked, and onEditPrefsLocked from the EditPrefs
execution path, defining when each step is performed and what behavior is allowed at each stage.

Currently, this is primarily used to support Always On mode, to handle the Exit Node enablement toggle,
and to report prefs edit metrics.

We then use it to enforce Exit Node policy settings by preventing users from setting an exit node
and making EditPrefs return an error when an exit node is restricted by policy. This enforcement is also
extended to the Exit Node toggle.

These changes prepare for supporting Exit Node overrides when permitted by policy and preventing logout
while Always On mode is enabled.

In the future, implementation of these methods can be delegated to ipnext extensions via the feature hooks.

Updates tailscale/corp#29969
Updates tailscale/corp#26249

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2025-07-07 17:18:00 -05:00
Nick Khyl
cb7b49941e ipn/ipnlocal: add (*LocalBackend).reconcilePrefsLocked
We have several places where we call applySysPolicy, suggestExitNodeLocked, and setExitNodeID.
While there are cases where we want to resolve the exit node specifically, such as when network
conditions change or a new netmap is received, we typically need to perform all three steps.
For example, enforcing policy settings may enable auto exit nodes or set an ExitNodeIP,
which in turn requires picking a suggested exit node or resolving the IP to an ID, respectively.

In this PR, we introduce (*LocalBackend).resolveExitNodeInPrefsLocked and (*LocalBackend).reconcilePrefsLocked,
with the latter calling both applySysPolicy and resolveExitNodeInPrefsLocked.

Consolidating these steps into a single extensibility point would also make it easier to support
future hooks registered by ipnext extensions.

Updates tailscale/corp#29969

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2025-07-07 16:09:18 -05:00
Nick Khyl
381fdcc3f1 ipn/ipnlocal,util/syspolicy/source: retain existing exit node when using auto exit node, if it's allowed by policy
In this PR, we update setExitNodeID to retain the existing exit node if auto exit node is enabled,
the current exit node is allowed by policy, and no suggested exit node is available yet.

Updates tailscale/corp#29969

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2025-07-07 15:38:30 -05:00
Nick Khyl
4c1c0bac8d ipn/ipnlocal: plumb nodeBackend into suggestExitNode to support delta updates, such as online status changes
Now that (*LocalBackend).suggestExitNodeLocked is never called with a non-current netmap
(the netMap parameter is always nil, indicating that the current netmap should be used),
we can remove the unused parameter.

Additionally, instead of suggestExitNodeLocked passing the most recent full netmap to suggestExitNode,
we now pass the current nodeBackend so it can access peers with delta updates applied.

Finally, with that fixed, we no longer need to skip TestUpdateNetmapDeltaAutoExitNode.

Updates tailscale/corp#29969
Fixes #16455

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2025-07-07 15:36:34 -05:00
Nick Khyl
a8055b5f40 cmd/tailscale/cli,ipn,ipn/ipnlocal: add AutoExitNode preference for automatic exit node selection
With this change, policy enforcement and exit node resolution can happen in separate steps,
since enforcement no longer depends on resolving the suggested exit node. This keeps policy
enforcement synchronous (e.g., when switching profiles), while allowing exit node resolution
to be asynchronous on netmap updates, link changes, etc.

Additionally, the new preference will be used to let GUIs and CLIs switch back to "auto" mode
after a manual exit node override, which is necessary for tailscale/corp#29969.

Updates tailscale/corp#29969
Updates #16459

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2025-07-03 14:12:25 -05:00
Nick Khyl
0098822981 ipn/ipnlocal: update suggestExitNode to skip offline candidates and fix TestSetControlClientStatusAutoExitNode
TestSetControlClientStatusAutoExitNode is broken similarly to TestUpdateNetmapDeltaAutoExitNode
as suggestExitNode didn't previously check the online status of exit nodes, and similarly to the other test
it succeeded because the test itself is also broken.

However, it is easier to fix as it sends out a full netmap update rather than a delta peer update,
so it doesn't depend on the same refactoring as TestSetControlClientStatusAutoExitNode.

Updates #16455
Updates tailscale/corp#29969

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2025-07-03 13:54:33 -05:00
Nick Khyl
6ecc25b26a ipn/ipnlocal: skip TestUpdateNetmapDeltaAutoExitNode
suggestExitNode never checks whether an exit node candidate is online.
It also accepts a full netmap, which doesn't include changes from delta updates.
The test can't work correctly until both issues are fixed.

Previously, it passed only because the test itself is flawed.
It doesn't succeed because the currently selected node goes offline and a new one is chosen.
Instead, it succeeds because lastSuggestedExitNode is incorrect, and suggestExitNode picks
the correct node the first time it runs, based on the DERP map and the netcheck report.
The node in exitNodeIDWant just happens to be the optimal choice.

Fixing SuggestExitNode requires refactoring its callers first, which in turn reveals the flawed test,
as suggestExitNode ends up being called slightly earlier.

In this PR, we update the test to correctly fail due to existing bugs in SuggestExitNode,
and temporarily skip it until those issues are addressed in a future commit.

Updates #16455
Updates tailscale/corp#29969

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2025-07-03 13:54:33 -05:00
kari-ts
d15b2312c4
tailcfg: add CapabilityOwner (#16426)
We would like to start sending whether a node is a Tailnet owner in netmap responses so that clients can determine what information to display to a user who wants to request account deletion.

Updates tailscale/corp#30016

Signed-off-by: kari-ts <kari@tailscale.com>
2025-07-01 09:28:48 -07:00
JerryYan
99aaa6e92c
ipn/ipnlocal: update PeerByID to return SelfNode and rename it to NodeByID (#16096)
Like NodeByKey, add an if stmt for checking the NodeId is SelfNode.

Updates #16052

Signed-off-by: Jerry Yan <792602257@qq.com>
2025-06-26 11:43:48 -05:00
Nick Khyl
9e28bfc69c ipn/ipnlocal,wgengine/magicsock: wait for magicsock to process pending events on authReconfig
Updates #16369

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2025-06-24 16:39:08 -05:00
Jordan Whited
fcab50b276
ipn/ipnlocal,wgengine{/magicsock}: replace SetNetworkMap with eventbus (#16299)
Same with UpdateNetmapDelta.

Updates tailscale/corp#27502
Updates #15160

Signed-off-by: Jordan Whited <jordan@tailscale.com>
2025-06-18 10:31:00 -07:00
James Sanderson
5716d0977d health: prefix Warnables received from the control plane
Updates tailscale/corp#27759

Signed-off-by: James Sanderson <jsanderson@tailscale.com>
2025-06-09 10:35:22 +01:00
KevinLiang10
7b06532ea1
ipn/ipnlocal: Update hostinfo to control on service config change (#16146)
This commit fixes the bug that c2n requests are skiped when updating vipServices in serveConfig. This then resulted
netmap update being skipped which caused inaccuracy of Capmap info on client side. After this fix, client always
inform control about it's vipServices config changes.

Fixes tailscale/corp#29219

Signed-off-by: KevinLiang10 <37811973+KevinLiang10@users.noreply.github.com>
2025-06-06 15:20:23 -04:00
James Sanderson
5fde183754 ipn: add watch opt to include actions in health messages
Updates tailscale/corp#27759

Signed-off-by: James Sanderson <jsanderson@tailscale.com>
2025-06-04 11:01:02 +01:00
James Sanderson
8a3afa5963 ipn/ipnlocal: fix deadlock when filtering DisplayMessage URLs
Updates tailscale/corp#27759

Signed-off-by: James Sanderson <jsanderson@tailscale.com>
2025-06-03 11:09:38 +01:00
James Sanderson
11e83f9da5 controlclient,health,ipnlocal,tailcfg: add DisplayMessage support
Updates tailscale/corp#27759

Signed-off-by: James Sanderson <jsanderson@tailscale.com>
2025-05-30 14:48:11 +01:00
James Sanderson
85a7abef0c tsnet: add test for packet filter generation from netmap
This is an integration test that covers all the code in Direct, Auto, and
LocalBackend that processes NetMaps and creates a Filter. The test uses
tsnet as a convenient proxy for setting up all the client pieces correctly,
but is not actually a test specific to tsnet.

Updates tailscale/corp#20514

Signed-off-by: James Sanderson <jsanderson@tailscale.com>
2025-05-08 17:18:30 +01:00
Nick Khyl
8b72dd7873 ipn/ipnlocal: add localNodeContext with netmap-related fields and methods
Updates #12614

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2025-04-25 15:44:10 -05:00
Brad Fitzpatrick
0c78f081a4 feature/taildrop: start moving Taildrop out of LocalBackend
This adds a feature/taildrop package, a ts_omit_taildrop build tag,
and starts moving code to feature/taildrop. In some cases, code
remains where it was but is now behind a build tag. Future changes
will move code to an extension and out of LocalBackend, etc.

Updates #12614

Change-Id: Idf96c61144d1a5f707039ceb2ff59c99f5c1642f
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2025-04-16 15:57:59 -07:00
David Anderson
5399fa159a net/netmon: publish events to event bus
Updates #15160

Signed-off-by: David Anderson <dave@tailscale.com>
2025-04-16 10:10:45 -07:00
M. J. Fromberger
deb0b255ff all: update the tsd.System constructor name (#15372)
Replace NewSystemWithEventBus with plain NewSystem, and update all usage.
See https://github.com/tailscale/tailscale/pull/15355#discussion_r2003910766

Updates #15160

Change-Id: I64d337f09576b41d9ad78eba301a74b9a9d6ebf4
Signed-off-by: M. J. Fromberger <fromberger@tailscale.com>
2025-04-16 10:10:45 -07:00
M. J. Fromberger
ffb22ee353 all: construct new System values with an event bus pre-populated
Although, at the moment, we do not yet require an event bus to be present, as
we start to add more pieces we will want to ensure it is always available.  Add
a new constructor and replace existing uses of new(tsd.System) throughout.
Update generated files for import changes.

Updates #15160

Change-Id: Ie5460985571ade87b8eac8b416948c7f49f0f64b
Signed-off-by: M. J. Fromberger <fromberger@tailscale.com>
2025-04-16 10:10:45 -07:00
Andrew Lytvynov
34b97a3c75
ipn/ipnlocal: fix TestOnTailnetDefaultAutoUpdate on macOS (#15697)
https://github.com/tailscale/tailscale/pull/15395 changed the logic to
skip `EditPrefs` when the platform doesn't support auto-updates. But the
old logic would only fail `EditPrefs` if the auto-update value was
`true`. If it was `false`, `EditPrefs` would succeed and store `false`
in prefs. The new logic will keep the value `unset` even if the tailnet
default is `false`.

Fixes #15691

Signed-off-by: Andrew Lytvynov <awly@tailscale.com>
2025-04-15 14:01:53 -07:00
Brad Fitzpatrick
4107056612 ipn/ipnlocal: skip broken TestOnTailnetDefaultAutoUpdate on macOS
Updates #15691

Change-Id: I131aed8bcd83be8e97399c905683e046381c9106
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2025-04-15 11:05:02 -07:00
Nick Khyl
94f4f83731 ipn, ipn/ipnlocal: reduce coupling between LocalBackend/profileManager and the Windows-specific "current user" model
Ultimately, we'd like to get rid of the concept of the "current user". It is only used on Windows,
but even then it doesn't work well in multi-user and enterprise/managed Windows environments.

In this PR, we update LocalBackend and profileManager to decouple them a bit more from this obsolete concept.
This is done in a preparation for extracting ipnlocal.Extension-related interfaces and types, and using them
to implement optional features like tailscale/corp#27645, instead of continuing growing the core ipnlocal logic.

Notably, we rename (*profileManager).SetCurrentUserAndProfile() to SwitchToProfile() and change its signature
to accept an ipn.LoginProfileView instead of an ipn.ProfileID and ipn.WindowsUserID. Since we're not removing
the "current user" completely just yet, the method sets the current user to the owner of the target profile.

We also update the profileResolver callback type, which is typically implemented by LocalBackend extensions,
to return an ipn.LoginProfileView instead of ipn.ProfileID and ipn.WindowsUserID.

Updates tailscale/corp#27645
Updates tailscale/corp#18342

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2025-04-10 12:24:00 -05:00
Nick Khyl
272854df41 ipn/ipnlocal: unconfigure wgengine when switching profiles
LocalBackend transitions to ipn.NoState when switching to a different (or new) profile.
When this happens, we should unconfigure wgengine to clear routes, DNS configuration,
firewall rules that block all traffic except to the exit node, etc.

In this PR, we update (*LocalBackend).enterStateLockedOnEntry to do just that.

Fixes #15316
Updates tailscale/corp#23967

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2025-03-28 10:31:45 -05:00
Nick Khyl
e07c1573f6 ipn/ipnlocal: do not reset the netmap and packet filter in (*LocalBackend).Start()
Resetting LocalBackend's netmap without also unconfiguring wgengine to reset routes, DNS, and the killswitch
firewall rules may cause connectivity issues until a new netmap is received.

In some cases, such as when bootstrap DNS servers are inaccessible due to network restrictions or other reasons,
or if the control plane is experiencing issues, this can result in a complete loss of connectivity until the user disconnects
and reconnects to Tailscale.

As LocalBackend handles state resets in (*LocalBackend).resetForProfileChangeLockedOnEntry(), and this includes
resetting the netmap, resetting the current netmap in (*LocalBackend).Start() is not necessary.
Moreover, it's harmful if (*LocalBackend).Start() is called more than once for the same profile.

In this PR, we update resetForProfileChangeLockedOnEntry() to reset the packet filter and remove
the redundant resetting of the netmap and packet filter from Start(). We also update the state machine
tests and revise comments that became inaccurate due to previous test updates.

Updates tailscale/corp#27173

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2025-03-20 13:18:23 -05:00
Irbe Krumina
f34e08e186
ipn: ensure that conffile is source of truth for advertised services. (#15361)
If conffile is used to configure tailscaled, always update
currently advertised services from conffile, even if they
are empty in the conffile, to ensure that it is possible
to transition to a state where no services are advertised.

Updates tailscale/corp#24795

Signed-off-by: Irbe Krumina <irbe@tailscale.com>
2025-03-20 14:40:36 +00:00
James Sanderson
27ef9b666c ipn/ipnlocal: add test for CapMap packet filters
Updates tailscale/corp#20514

Signed-off-by: James Sanderson <jsanderson@tailscale.com>
2025-03-17 11:24:54 +00:00