Commit Graph
35 Commits
Author SHA1 Message Date
Nick KhylandNick Khyl aeb15dea30 util/syspolicy/source: add package for reading policy settings from external stores
We add package defining interfaces for policy stores, enabling creation of policy sources
and reading settings from them. It includes a Windows-specific PlatformPolicyStore for GP and MDM
policies stored in the Registry, and an in-memory TestStore for testing purposes.

We also include an internal package that tracks and reports policy usage metrics when a policy setting
is read from a store. Initially, it will be used only on Windows and Android, as macOS, iOS, and tvOS
report their own metrics. However, we plan to use it across all platforms eventually.

Updates #12687

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2024-09-03 14:51:14 -05:00
Nick KhylandNick Khyl 2f2aeaeaeb ipn/ipnlocal: fix a nil pointer dereference when serving /localapi/v0/tka/status
Fixes #13330

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2024-08-30 23:13:44 -05:00
Nick KhylandNick Khyl 959285e0c5 ipn/ipnlocal: fix race condition that results in a panic sending on a closed channel
Fixes #13288

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2024-08-29 17:27:21 -05:00
Nick KhylandNick Khyl b48c8db69c ipn/ipnlocal: set WantRunning upon an interactive login, but not during a seamless renewal or a profile switch
The LocalBackend's state machine starts in NoState and soon transitions to NeedsLogin if there's no auto-start profile,
with the profileManager starting with a new empty profile. Notably, entering the NeedsLogin state blocks engine updates.
We expect the user to transition out of this state by logging in interactively, and we set WantRunning to true when
controlclient enters the StateAuthenticated state.

While our intention is correct, and completing an interactive login should set WantRunning to true, our assumption
that logging into the current Tailscale profile is the only way to transition out of the NeedsLogin state is not accurate.
Another common transition path includes an explicit profile switch (via LocalBackend.SwitchProfile) or an implicit switch
when a Windows user connects to the backend. This results in a bug where WantRunning is set to true even when it was
previously set to false, and the user expressed no intention of changing it.

A similar issue occurs when switching from (sic) a Tailnet that has seamlessRenewalEnabled, regardless of the current state
of the LocalBackend's state machine, and also results in unexpectedly set WantRunning. While this behavior is generally
undesired, it is also incorrect that it depends on the control knobs of the Tailnet we're switching from rather than
the Tailnet we're switching to. However, this issue needs to be addressed separately.

This PR updates LocalBackend.SetControlClientStatus to only set WantRunning to true in response to an interactive login
as indicated by a non-empty authURL.

Fixes #6668
Fixes #11280
Updates #12756

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2024-08-29 09:27:17 -05:00
Nick KhylandNick Khyl 80b2b45d60 ipn/ipnlocal: refactor and cleanup profileManager
In preparation for multi-user and unattended mode improvements, we are
refactoring and cleaning up `ipn/ipnlocal.profileManager`. The concept of the
"current user", which is only relevant on Windows, is being deprecated and will
soon be removed to allow more than one Windows user to connect and utilize
`LocalBackend` according to that user's access rights to the device and specific
Tailscale profiles.

We plan to pass the user's identity down to the `profileManager`, where it can
be used to determine the user's access rights to a given `LoginProfile`. While
the new permission model in `ipnauth` requires more work and is currently
blocked pending PR reviews, we are updating the `profileManager` to reduce its
reliance on the concept of a single OS user being connected to the backend at
the same time.

We extract the switching to the default Tailscale profile, which may also
trigger legacy profile migration, from `profileManager.SetCurrentUserID`. This
introduces `profileManager.DefaultUserProfileID`, which returns the default
profile ID for the current user, and `profileManager.SwitchToDefaultProfile`,
which is essentially a shorthand for `pm.SwitchProfile(pm.DefaultUserProfileID())`.
Both methods will eventually be updated to accept the user's identity and
utilize that user's default profile.

We make access checks more explicit by introducing the `profileManager.checkProfileAccess`
method. The current implementation continues to use `profileManager.currentUserID`
and `LoginProfile.LocalUserID` to determine whether access to a given profile
should be granted. This will be updated to utilize the `ipnauth` package and the
new permissions model once it's ready. We also expand access checks to be used
more widely in the `profileManager`, not just when switching or listing
profiles. This includes access checks in methods like `SetPrefs` and, most notably,
`DeleteProfile` and `DeleteAllProfiles`, preventing unprivileged Windows users
from deleting Tailscale profiles owned by other users on the same device,
including profiles owned by local admins.

We extract `profileManager.ProfilePrefs` and `profileManager.SetProfilePrefs`
methods that can be used to get and set preferences of a given `LoginProfile` if
`profileManager.checkProfileAccess` permits access to it.

We also update `profileManager.setUnattendedModeAsConfigured` to always enable
unattended mode on Windows if `Prefs.ForceDaemon` is true in the current
`LoginProfile`, even if `profileManager.currentUserID` is `""`. This facilitates
enabling unattended mode via `tailscale up --unattended` even if
`tailscale-ipn.exe` is not running, such as when a Group Policy or MDM-deployed
script runs at boot time, or when Tailscale is used on a Server Code or otherwise
headless Windows environments. See #12239, #2137, #3186 and
https://github.com/tailscale/tailscale/pull/6255#issuecomment-2016623838 for
details.

Fixes #12239
Updates tailscale/corp#18342
Updates #3186
Updates #2137

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2024-08-28 14:42:35 -05:00
Nick KhylandNick Khyl 961ee321e8 ipn/{ipnauth,ipnlocal,ipnserver,localapi}: start baby step toward moving access checks from the localapi.Handler to the LocalBackend
Currently, we use PermitRead/PermitWrite/PermitCert permission flags to determine which operations are allowed for a LocalAPI client.
These checks are performed when localapi.Handler handles a request. Additionally, certain operations (e.g., changing the serve config)
requires the connected user to be a local admin. This approach is inherently racey and is subject to TOCTOU issues.
We consider it to be more critical on Windows environments, which are inherently multi-user, and therefore we prevent more than one
OS user from connecting and utilizing the LocalBackend at the same time. However, the same type of issues is also applicable to other
platforms when switching between profiles that have different OperatorUser values in ipn.Prefs.

We'd like to allow more than one Windows user to connect, but limit what they can see and do based on their access rights on the device
(e.g., an local admin or not) and to the currently active LoginProfile (e.g., owner/operator or not), while preventing TOCTOU issues on Windows
and other platforms. Therefore, we'd like to pass an actor from the LocalAPI to the LocalBackend to represent the user performing the operation.
The LocalBackend, or the profileManager down the line, will then check the actor's access rights to perform a given operation on the device
and against the current (and/or the target) profile.

This PR does not change the current permission model in any way, but it introduces the concept of an actor and includes some preparatory
work to pass it around. Temporarily, the ipnauth.Actor interface has methods like IsLocalSystem and IsLocalAdmin, which are only relevant
to the current permission model. It also lacks methods that will actually be used in the new model. We'll be adding these gradually in the next
PRs and removing the deprecated methods and the Permit* flags at the end of the transition.

Updates tailscale/corp#18342

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2024-08-28 13:49:58 -05:00
Nick KhylandNick Khyl 03acab2639 cmd/cloner, cmd/viewer, util/codegen: add support for aliases of cloneable types
We have several checked type assertions to *types.Named in both cmd/cloner and cmd/viewer.
As Go 1.23 updates the go/types package to produce Alias type nodes for type aliases,
these type assertions no longer work as expected unless the new behavior is disabled
with gotypesalias=0.

In this PR, we add codegen.NamedTypeOf(t types.Type), which functions like t.(*types.Named)
but also unrolls type aliases. We then use it in place of type assertions in the cmd/cloner and
cmd/viewer packages where appropriate.

We also update type switches to include *types.Alias alongside *types.Named in relevant cases,
remove *types.Struct cases when switching on types.Type.Underlying and update the tests
with more cases where type aliases can be used.

Updates #13224
Updates #12912

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2024-08-23 15:43:40 -05:00
Nick KhylandNick Khyl a9dc6e07ad util/codegen, cmd/cloner, cmd/viewer: update codegen.LookupMethod to support alias type nodes
Go 1.23 updates the go/types package to produce Alias type nodes for type aliases, unless disabled with gotypesalias=0.
This new default behavior breaks codegen.LookupMethod, which uses checked type assertions to types.Named and
types.Interface, as only named types and interfaces have methods.

In this PR, we update codegen.LookupMethod to perform method lookup on the right-hand side of the alias declaration
and clearly switch on the supported type nodes types. We also improve support for various edge cases, such as when an alias
is used as a type parameter constraint, and add tests for the LookupMethod function.

Additionally, we update cmd/viewer/tests to include types with aliases used in type fields and generic type constraints.

Updates #13224
Updates #12912

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2024-08-23 15:26:05 -05:00
Nick KhylandNick Khyl af3d3c433b types/prefs: add a package containing generic preference types
This adds a new package containing generic types to be used for defining preference hierarchies.
These include prefs.Item, prefs.List, prefs.StructList, and prefs.StructMap. Each of these types
represents a configurable preference, holding the preference's state, value, and metadata.
The metadata includes the default value (if it differs from the zero value of the Go type)
and flags indicating whether a preference is managed via syspolicy or is hidden/read-only for
another reason. This information can be marshaled and sent to the GUI, CLI and web clients
as a source of truth regarding preference configuration, management, and visibility/mutability states.

We plan to use these types to define device preferences, such as the updater preferences,
the permission mode to be used on Windows with #tailscale/corp#18342, and certain global options
that are currently exposed as tailscaled flags. We also aim to eventually use these types for
profile-local preferences in ipn.Prefs and and as a replacement for ipn.MaskedPrefs.

The generic preference types are compatible with the tailscale.com/cmd/viewer and
tailscale.com/cmd/cloner utilities.

Updates #12736

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2024-08-21 12:44:38 -05:00
Nick KhylandNick Khyl f8f9f05ffe cmd/viewer: add support for map-like container types
This PR modifies viewTypeForContainerType to use the last type parameter of a container type
as the value type, enabling the implementation of map-like container types where the second-to-last
(usually first) type parameter serves as the key type.

It also adds a MapContainer type to test the code generation.

Updates #12736

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2024-08-14 16:33:51 -05:00
Nick KhylandNick Khyl 67df9abdc6 util/syspolicy/setting: add package that contains types for the next syspolicy PRs
Package setting contains types for defining and representing policy settings.
It facilitates the registration of setting definitions using Register and RegisterDefinition,
and the retrieval of registered setting definitions via Definitions and DefinitionOf.
This package is intended for use primarily within the syspolicy package hierarchy,
and added in a preparation for the next PRs.

Updates #12687

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2024-08-12 21:02:35 -05:00
Nick KhylandNick Khyl f23932bd98 net/dns/resolver: log forwarded query details when TS_DEBUG_DNS_FORWARD_SEND is enabled
Troubleshooting DNS resolution issues often requires additional information.
This PR expands the effect of the TS_DEBUG_DNS_FORWARD_SEND envknob to forwarder.forwardWithDestChan,
and includes the request type, domain name length, and the first 3 bytes of the domain's SHA-256 hash in the output.

Fixes #13070

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2024-08-08 15:57:35 -05:00
Nick KhylandNick Khyl 4099a36468 util/winutil/gp: fix a busy loop bug
Updates #12687

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2024-08-02 20:16:41 -05:00
Nick KhylandNick Khyl 43375c6efb types/lazy: re-init SyncValue during test cleanup if it wasn't set before SetForTest
Updates #12687

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2024-07-24 11:47:58 -05:00
Nick KhylandNick Khyl 5d09649b0b types/lazy: add (*SyncValue[T]).SetForTest method
It is sometimes necessary to change a global lazy.SyncValue for the duration of a test. This PR adds a (*SyncValue[T]).SetForTest method to facilitate that.

Updates #12687

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2024-07-22 15:10:31 -05:00
Nick KhylandNick Khyl d500a92926 util/slicesx: add HasPrefix, HasSuffix, CutPrefix, and CutSuffix functions
The standard library includes these for strings and byte slices,
but it lacks similar functions for generic slices of comparable types.
Although they are not as commonly used, these functions are useful
in scenarios such as working with field index sequences (i.e., []int)
via reflection.

Updates #12687

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2024-07-22 11:03:46 -05:00
Nick KhylandNick Khyl bd54b61746 types/opt: add (Value[T]).GetOr(def T) T method
Updates #12736

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2024-07-19 15:50:24 -05:00
Nick KhylandNick Khyl 20562a4fb9 cmd/viewer, types/views, util/codegen: add viewer support for custom container types
This adds support for container-like types such as Container[T] that
don't explicitly specify a view type for T. Instead, a package implementing
a container type should also implement and export a ContainerView[T, V] type
and a ContainerViewOf(*Container[T]) ContainerView[T, V] function, which
returns a view for the specified container, inferring the element view type V
from the element type T.

Updates #12736

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2024-07-19 12:50:39 -05:00
Nick KhylandNick Khyl 1608831c33 wgengine/router: use quad-100 as the nexthop on Windows
Windows requires routes to have a nexthop. Routes created using the interface's local IP address or an unspecified IP address ("0.0.0.0" or "::") as the nexthop are considered on-link routes. Notably, Windows treats on-link subnet routes differently, reserving the last IP in the range as the broadcast IP and therefore prohibiting TCP connections to it, resulting in WSA error 10049: "The requested address is not valid in its context. This does not happen with single-host routes, such as routes to Tailscale IP addresses, but becomes a problem with advertised subnets when all IPs in the range should be reachable.

Before Windows 8, only routes created with an unspecified IP address were considered on-link, so our previous approach of using the interface's own IP as the nexthop likely worked on Windows 7.

This PR updates configureInterface to use the TailscaleServiceIP (100.100.100.100) and its IPv6 counterpart as the nexthop for subnet routes.

Fixes tailscale/support-escalations#57

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2024-07-18 10:08:29 -05:00
Nick KhylandNick Khyl fd0acc4faf cmd/cloner, cmd/viewer: add _test prefix for files generated with the test build tag
Updates #12736

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2024-07-12 15:31:34 -05:00
Nick KhylandNick Khyl fc28c8e7f3 cmd/cloner, cmd/viewer, util/codegen: add support for generic types and interfaces
This adds support for generic types and interfaces to our cloner and viewer codegens.
It updates these packages to determine whether to make shallow or deep copies based
on the type parameter constraints. Additionally, if a template parameter or an interface
type has View() and Clone() methods, we'll use them for getters and the cloner of the
owning structure.

Updates #12736

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2024-07-11 16:38:53 -05:00
Nick KhylandNick Khyl 726d5d507d cmd/k8s-operator: update depaware.txt
This fixes an issue caused by the merge order of 2b638f550d and 8bd442ba8c.

Updates #Cleanup

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2024-07-08 23:02:27 -05:00
Nick KhylandNick Khyl 8bd442ba8c util/winutil/gp, net/dns: add package for Group Policy API
This adds a package with GP-related functions and types to be used in the future PRs.
It also updates nrptRuleDatabase to use the new package instead of its own gpNotificationWatcher implementation.

Updates #12687

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2024-07-08 20:37:03 -05:00
Nick KhylandNick Khyl e21d8768f9 types/opt: add generic Value[T any] for optional values of any types
Updates #12736

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2024-07-08 17:00:43 -05:00
Nick KhylandNick Khyl c32efd9118 various: create a catch-all NRPT rule when "Override local DNS" is enabled on Windows
Without this rule, Windows 8.1 and newer devices issue parallel DNS requests to DNS servers
associated with all network adapters, even when "Override local DNS" is enabled and/or
a Mullvad exit node is being used, resulting in DNS leaks.

This also adds "disable-local-dns-override-via-nrpt" nodeAttr that can be used to disable
the new behavior if needed.

Fixes tailscale/corp#20718

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2024-06-14 14:41:50 -05:00
Nick KhylandNick Khyl 4cdc4ed7db net/dns/resolver: return an empty successful response instead of NXDomain when resolving A records for 4via6 domains
As quad-100 is an authoritative server for 4via6 domains, it should always return responses
with a response code of 0 (indicating no error) when resolving records for these domains.
If there's no resource record of the specified type (e.g. A), it should return a response
with an empty answer section rather than NXDomain. Such a response indicates that there
is at least one RR of a different type (e.g., AAAA), suggesting the Windows stub resolver
to look for it.

Fixes tailscale/corp#20767

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2024-06-11 09:43:48 -05:00
Nick KhylandNick Khyl 3672f66c74 tailcfg: bump capver for NodeAttrDisableSplitDNSWhenNoCustomResolvers
Missed in b65221999c.

Updates tailscale/corp#15802

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2024-06-10 18:05:08 -05:00
Nick KhylandNick Khyl f62e678df8 net/dns/resolver, control/controlknobs, tailcfg: use UserDial instead of SystemDial to dial DNS servers
Now that tsdial.Dialer.UserDial has been updated to honor the configured routes
and dial external network addresses without going through Tailscale, while also being
able to dial a node/subnet router on the tailnet, we can start using UserDial to forward
DNS requests. This is primarily needed for DNS over TCP when forwarding requests
to internal DNS servers, but we also update getKnownDoHClientForProvider to use it.

Updates tailscale/corp#18725

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2024-05-06 17:29:24 -05:00
Nick KhylandNick Khyl caa3d7594f ipn/ipnlocal, net/tsdial: plumb routes into tsdial and use them in UserDial
We'd like to use tsdial.Dialer.UserDial instead of SystemDial for DNS over TCP.
This is primarily necessary to properly dial internal DNS servers accessible
over Tailscale and subnet routes. However, to avoid issues when switching
between Wi-Fi and cellular, we need to ensure that we don't retain connections
to any external addresses on the old interface. Therefore, we need to determine
which dialer to use internally based on the configured routes.

This plumbs routes and localRoutes from router.Config to tsdial.Dialer,
and updates UserDial to use either the peer dialer or the system dialer,
depending on the network address and the configured routes.

Updates tailscale/corp#18725
Fixes #4529

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2024-05-06 15:44:44 -05:00
Nick KhylandNick Khyl 9e1c86901b wgengine\router: fix the Tailscale-In firewall rule to work on domain networks
The Network Location Awareness service identifies networks authenticated against
an Active Directory domain and categorizes them as "Domain Authenticated".
This includes the Tailscale network if a Domain Controller is reachable through it.

If a network is categories as NLM_NETWORK_CATEGORY_DOMAIN_AUTHENTICATED,
it is not possible to override its category, and we shouldn't attempt to do so.
Additionally, our Windows Firewall rules should be compatible with both private
and domain networks.

This fixes both issues.

Fixes #11813

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2024-04-19 15:43:15 -05:00
Nick KhylandNick Khyl 8d83adde07 util/winutil/winenv: add package for current Windows environment details
Package winenv provides information about the current Windows environment.
This includes details such as whether the device is a server or workstation,
and if it is AD domain-joined, MDM-registered, or neither.

Updates tailscale/corp#18342

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2024-04-09 13:25:37 -05:00
Nick KhylandNick Khyl 7ef1fb113d cmd/tailscaled, ipn/ipnlocal, wgengine: shutdown tailscaled if wgdevice is closed
Tailscaled becomes inoperative if the Tailscale Tunnel wintun adapter is abruptly removed.
wireguard-go closes the device in case of a read error, but tailscaled keeps running.
This adds detection of a closed WireGuard device, triggering a graceful shutdown of tailscaled.
It is then restarted by the tailscaled watchdog service process.

Fixes #11222

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2024-02-26 14:45:35 -06:00
Nick KhylandNick Khyl b42b9817b0 net/dns: do not wait for the interface registry key to appear if the windowsManager is being closed
The WinTun adapter may have been removed by the time we're closing
the dns.windowsManager, and its associated interface registry key might
also have been deleted. We shouldn't use winutil.OpenKeyWait and wait
for the interface key to appear when performing a cleanup as a part of
the windowsManager shutdown.

Updates #11222

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2024-02-26 14:45:35 -06:00
Nick KhylandNick Khyl c9836b454d net/netmon: fix goroutine leak in winMon if the monitor is never started
When the portable Monitor creates a winMon via newOSMon, we register
address and route change callbacks with Windows. Once a callback is hit,
it starts a goroutine that attempts to send the event into messagec and returns.
The newly started goroutine then blocks until it can send to the channel.
However, if the monitor is never started and winMon.Receive is never called,
the goroutines remain indefinitely blocked, leading to goroutine leaks and
significant memory consumption in the tailscaled service process on Windows.
Unlike the tailscaled subprocess, the service process creates but never starts
a Monitor.

This PR adds a check within the callbacks to confirm the monitor's active status,
and exits immediately if the monitor hasn't started.

Updates #9864

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2023-12-21 16:36:52 -06:00
Nick KhylandNick Khyl 5e3126f510 tool/gocross: make all Windows DLLs build with static libgcc
In this commit, we have updated the build process for our Windows DLLs
to link statically with libgcc, ensuring our Windows DLLs are self-contained.

Updates #10617

Signed-off-by: Nick Khyl <nickk@tailscale.com>
2023-12-19 15:10:28 -06:00