On Windows, the idiomatic way to check access on a named pipe is for
the server to impersonate the client on its current OS thread, perform
access checks using the client's access token, and then revert the OS
thread's access token back to its true self.
The access token is a better representation of the client's rights than just
a username/userid check, as it represents the client's effective rights
at connection time, which might differ from their normal rights.
This patch updates safesocket to do the aforementioned impersonation,
extract the token handle, and then revert the impersonation. We retain
the token handle for the remaining duration of the connection (the token
continues to be valid even after we have reverted back to self).
Since the token is a property of the connection, I changed ipnauth to wrap
the concrete net.Conn to include the token. I then plumbed that change
through ipnlocal, ipnserver, and localapi as necessary.
I also added a PermitLocalAdmin flag to the localapi Handler which I intend
to use for controlling access to a few new localapi endpoints intended
for configuring auto-update.
Updates https://github.com/tailscale/tailscale/issues/755
Signed-off-by: Aaron Klotz <aaron@tailscale.com>
It would end up resetting whatever hostinfo we had constructed
and leave the backend statemachine in a broken state.
This fixes that by storing the PushDeviceToken on the LocalBackend
and populating it on Hostinfo before passing it to controlclient.
Updates tailscale/corp#8940
Updates tailscale/corp#15367
Signed-off-by: Maisem Ali <maisem@tailscale.com>
The value being passed was the same as whats on b.hostinfo, so just
use that directly.
Updates #cleanup
Signed-off-by: Maisem Ali <maisem@tailscale.com>
This adds a check to prevent changes to ServeConfig if tailscaled
is run with a Locked config.
Missed in 1fc3573446.
Updates #1412
Signed-off-by: Maisem Ali <maisem@tailscale.com>
Ensure that when a userspace proxy config is reloaded,
connections for any removed proxies are safely closed
Updates tailscale/tailscale#9725
Signed-off-by: Irbe Krumina <irbe@tailscale.com>
File resumption requires keeping partial files around for some time,
but we must still eventually delete them if never resumed.
Thus, we implement asynchronous file deletion, which could
spawn a background goroutine to delete the files.
We also use the same mechanism for deleting files on Windows,
where a file can't be deleted if there is still an open file handle.
We can enqueue those with the asynchronous file deleter as well.
Updates tailscale/corp#14772
Signed-off-by: Joe Tsai <joetsai@digital-static.net>
The old code would always retain value `true` if it was set once, even
if you then change `prefs.AutoUpdate.Apply` to `false`.
Instead of using the previous value, use the default (envknob) value to
OR with.
Updates #755
Signed-off-by: Andrew Lytvynov <awly@tailscale.com>
We add the following API:
* type FileChecksums
* type Checksum
* func Manager.PartialFiles
* func Manager.HashPartialFile
* func ResumeReader
The Manager methods provide the ability to query for partial files
and retrieve a list of checksums for a given partial file.
The ResumeReader function is a helper that wraps an io.Reader
to discard content that is identical locally and remotely.
The FileChecksums type represents the checksums of a file
and is safe to JSON marshal and send over the wire.
Updates tailscale/corp#14772
Signed-off-by: Joe Tsai <joetsai@digital-static.net>
Co-authored-by: Rhea Ghosh <rhea@tailscale.com>
Changes made:
* Move all HTTP related functionality from taildrop to ipnlocal.
* Add two arguments to taildrop.Manager.PutFile to specify
an opaque client ID and a resume offset (both unused for now).
* Cleanup the logic of taildrop.Manager.PutFile
to be easier to follow.
* Implement file conflict handling where duplicate files are renamed
(e.g., "IMG_1234.jpg" -> "IMG_1234 (2).jpg").
* Implement file de-duplication where "renaming" a partial file
simply deletes it if it already exists with the same contents.
* Detect conflicting active puts where a second concurrent put
results in an error.
Updates tailscale/corp#14772
Signed-off-by: Joe Tsai <joetsai@digital-static.net>
Co-authored-by: Rhea Ghosh <rhea@tailscale.com>
Changes made:
* Unexport declarations specific to internal taildrop functionality.
* Document all exported functionality.
* Move TestRedactErr to the taildrop package.
* Rename and invert Handler.DirectFileDoFinalRename as AvoidFinalRename.
Updates tailscale/corp#14772
Signed-off-by: Joe Tsai <joetsai@digital-static.net>
Over time all taildrop functionality will be contained in the
taildrop package. This will include end to end unit tests. This is
simply the first smallest piece to move over.
There is no functionality change in this commit.
Updates tailscale/corp#14772
Signed-off-by: Rhea Ghosh <rhea@tailscale.com>
Co-authored-by: Joseph Tsai <joetsai@tailscale.com>
Advertise it on Android (it looks like it already works once advertised).
And both advertise & likely fix it on iOS. Yet untested.
Updates #9672
Change-Id: If3b7e97f011dea61e7e75aff23dcc178b6cf9123
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Make the 'tailscale debug component-logs' command print the component names for
which extra logging can be turned on, for easier discoverability of debug
functions.
Updates #cleanup
Co-authored-by: Paul Scott <paul@tailscale.com>
Signed-off-by: Val <valerie@tailscale.com>
Thanks to @qur and @eric for debugging!
Fixes#6973
Change-Id: Ib2cf8f030cf595cc73dd061c72e78ac19f5fae5d
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Control sends ExitNodeDNSResolvers when configured for IsWireGuardOnly
nodes that are to be used as the default resolver with a lower
precedence than split DNS, and a lower precedence than "Override local
DNS", but otherwise before local DNS is used when the exit node is in
use.
Neither of the below changes were problematic, but appeared so alongside
a number of other client and external changes. See tailscale/corp#14809.
Reland ea9dd8fabc.
Reland d52ab181c3.
Updates #9377
Updates tailscale/corp#14809
Signed-off-by: James Tucker <james@tailscale.com>
This PR ensures zombie foregrounds are shutdown if a new
ServeConfig is created that wipes the ongoing foreground ones.
For example, "tailscale serve|funnel reset|off" should close
all open sessions.
Updates #8489
Signed-off-by: Marwan Sulaiman <marwan@tailscale.com>
For loading testing & profiling the cost of full netmap updates.
Updates #1909
Change-Id: I0afdf5de9967f8d95c7f81d5b531ed1c92c3208f
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
9538e9f970 broke LocalBackend.WhoIs
where you can no longer lookup yourself in WhoIs.
This occurs because the LocalBackend.peers map only contains peers.
If we fail to lookup a peer, double-check whether it is ourself.
Fixes#9470
Signed-off-by: Joe Tsai <joetsai@digital-static.net>
Co-authored-by: Rhea Ghosh <rhea@tailscale.com>
The initial implementation directly mirrored the behavior of Tailscale
exit nodes, where the WireGuard exit node DNS took precedence over other
configuration.
This adjusted implementation treats the WireGuard DNS
resolvers as a lower precedence default resolver than the tailnet
default resolver, and allows split DNS configuration as well.
This also adds test coverage to the existing DNS selection behavior with
respect to default resolvers and split DNS routes for Tailscale exit
nodes above cap 25. There may be some refinement to do in the logic in
those cases, as split DNS may not be working as we intend, though that
would be a pre-existing and separate issue.
Updates #9377
Signed-off-by: James Tucker <james@tailscale.com>
Like PeerCapMap, add a field to `tailcfg.Node` which provides
a map of Capability to raw JSON messages which are deferred to be
parsed later by the application code which cares about the specific
capabilities. This effectively allows us to prototype new behavior
without having to commit to a schema in tailcfg, and it also opens up
the possibilities to develop custom behavior in tsnet applications w/o
having to plumb through application specific data in the MapResponse.
Updates #4217
Signed-off-by: Maisem Ali <maisem@tailscale.com>
And convert all callers over to the methods that check SelfNode.
Now we don't have multiple ways to express things in tests (setting
fields on SelfNode vs NetworkMap, sometimes inconsistently) and don't
have multiple ways to check those two fields (often only checking one
or the other).
Updates #9443
Change-Id: I2d7ba1cf6556142d219fae2be6f484f528756e3c
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
We have some flaky integration tests elsewhere that have no one place
to ask about the state of the world. This makes LocalBackend be that
place (as it's basically there anyway) but doesn't yet add the ForTest
accessor method.
This adds a LocalBackend.peers map[NodeID]NodeView that is
incrementally updated as mutations arrive. And then we start moving
away from using NetMap.Peers at runtime (UpdateStatus no longer uses
it now). And remove another copy of NodeView in the LocalBackend
nodeByAddr map. Change that to point into b.peers instead.
Future changes will then start streaming whole-node-granularity peer
change updates to WatchIPNBus clients, tracking statefully per client
what each has seen. This will get the GUI clients from receiving less
of a JSON storm of updates all the time.
Updates #1909
Change-Id: I14a976ca9f493bdf02ba7e6e05217363dcf422e5
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
NetworkMap.Addresses is redundant with the SelfNode.Addresses. This
works towards a TODO to delete NetworkMap.Addresses and replace it
with a method.
This is similar to #9389.
Updates #cleanup
Change-Id: Id000509ca5d16bb636401763d41bdb5f38513ba0
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
* Remove unnecessary mutexes (there's no concurrency)
* Simplify LocalBackend.UpdateStatus using the StatusBuilder.WantPeers
field that was added in 0f604923d3, removing passing around some
method values into func args. And then merge two methods.
More remains, but this is a start.
Updates #9433
Change-Id: Iaf2d7ec6e4e590799f00bae185465a4fd089b822
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
This enables installing default resolvers specified by
tailcfg.Node.ExitNodeDNSResolvers when the exit node is selected.
Updates #9377
Signed-off-by: James Tucker <james@tailscale.com>
It has one user (LocalBackend) which can ask magicsock itself.
Updates #cleanup
Change-Id: I8c03cbb1e5ba57b0b442621b5fa467030c14a2e2
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
(continuing the mission of removing rando methods from the Engine
interface that we don't need anymore)
Updates #cleanup
Change-Id: Id5190917596bf04d7185c3b331a852724a3f5a16
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
We always have one. Stop pretending we might not.
Instead, add one early panic in NewLocalBackend if we actually don't.
Updates #cleanup
Change-Id: Iba4b78ed22cb6248e59c2b01a79355ca7a200ec8
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
LocalBackend can talk to magicsock on its own to do this without
the "Engine" being involved.
(Continuing a little side quest of cleaning up the Engine
interface...)
Updates #cleanup
Change-Id: I8654acdca2b883b1bd557fdc0cfb90cd3a418a62
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
It had exactly one user: netstack. Just have LocalBackend notify
netstack when here's a new netmap instead, simplifying the bloated
Engine interface that has grown a bunch of non-Engine-y things.
(plenty of rando stuff remains after this, but it's a start)
Updates #cleanup
Change-Id: I45e10ab48119e962fc4967a95167656e35b141d8
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Currently only the top four most popular changes: endpoints, DERP
home, online, and LastSeen.
Updates #1909
Change-Id: I03152da176b2b95232b56acabfb55dcdfaa16b79
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
I missed connecting some controlknobs.Knobs pieces in 4e91cf20a8
resulting in that breaking control knobs entirely.
Whoops.
The fix in ipn/ipnlocal (where it makes a new controlclient) but to
atone, I also added integration tests. Those integration tests use
a new "tailscale debug control-knobs" which by itself might be useful
for future debugging.
Updates #9351
Change-Id: Id9c89c8637746d879d5da67b9ac4e0d2367a3f0d
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Previously two tsnet nodes in the same process couldn't have disjoint
sets of controlknob settings from control as both would overwrite each
other's global variables.
This plumbs a new controlknobs.Knobs type around everywhere and hangs
the knobs sent by control on that instead.
Updates #9351
Change-Id: I75338646d36813ed971b4ffad6f9a8b41ec91560
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
All platforms use it at this point, including iOS which was the
original hold out for memory reasons. No more reason to make it
optional.
Updates #9332
Change-Id: I743fbc2f370921a852fbcebf4eb9821e2bdd3086
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Cache the last `ClientVersion` value that was received from coordination
server and pass it in the localapi `/status` response.
When running `tailscale status`, print a message if `RunningAsLatest` is
`false`.
Updates #6907
Signed-off-by: Andrew Lytvynov <awly@tailscale.com>
Log some progress info to make updates more debuggable. Also, track
whether an active update is already started and return an error if
a concurrent update is attempted.
Some planned future PRs:
* add JSON output to `tailscale update`
* use JSON output from `tailscale update` to provide a more detailed
status of in-progress update (stage, download progress, etc)
Updates #6907
Signed-off-by: Andrew Lytvynov <awly@tailscale.com>
This PR adds a new field to the serve config that can be used to identify which serves are in "foreground mode" and then can also be used to ensure they do not get persisted to disk so that if Tailscaled gets ungracefully shutdown, the reloaded ServeConfig will not have those ports opened.
Updates #8489
Signed-off-by: Marwan Sulaiman <marwan@tailscale.com>
This PR removes the per request logging to the CLI as the CLI
will not be displaying those logs initially.
Updates #8489
Signed-off-by: Marwan Sulaiman <marwan@tailscale.com>
This PR adds a new field to the ServeConfig which maps
WatchIPNBus session ids to foreground serve configs.
The PR also adds a DeleteForegroundSession method to ensure the config
gets cleaned up on sessions ending.
Note this field is not currently used but will be in follow up work.
Updates #8489
Signed-off-by: Marwan Sulaiman <marwan@tailscale.com>
It would acquire the lock, calculate `nextState`, relase
the lock, then call `enterState` which would acquire the lock
again. There were obvious races there which could lead to
nil panics as seen in a test in a different repo.
```
panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x2 addr=0x70 pc=0x1050f2c7c]
goroutine 42240 [running]:
tailscale.com/ipn/ipnlocal.(*LocalBackend).enterStateLockedOnEntry(0x14002154e00, 0x6)
tailscale.com/ipn/ipnlocal/local.go:3715 +0x30c
tailscale.com/ipn/ipnlocal.(*LocalBackend).enterState(0x14002154e00?, 0x14002e3a140?)
tailscale.com/ipn/ipnlocal/local.go:3663 +0x8c
tailscale.com/ipn/ipnlocal.(*LocalBackend).stateMachine(0x14001f5e280?)
tailscale.com/ipn/ipnlocal/local.go:3836 +0x2c
tailscale.com/ipn/ipnlocal.(*LocalBackend).setWgengineStatus(0x14002154e00, 0x14002e3a190, {0x0?, 0x0?})
tailscale.com/ipn/ipnlocal/local.go:1193 +0x4d0
tailscale.com/wgengine.(*userspaceEngine).RequestStatus(0x14005d90300)
tailscale.com/wgengine/userspace.go:1051 +0x80
tailscale.com/wgengine.NewUserspaceEngine.func2({0x14002e3a0a0, 0x2, 0x140025cce40?})
tailscale.com/wgengine/userspace.go:318 +0x1a0
tailscale.com/wgengine/magicsock.(*Conn).updateEndpoints(0x14002154700, {0x105c13eaf, 0xf})
tailscale.com/wgengine/magicsock/magicsock.go:531 +0x424
created by tailscale.com/wgengine/magicsock.(*Conn).ReSTUN in goroutine 42077
tailscale.com/wgengine/magicsock/magicsock.go:2142 +0x3a4
```
Updates tailscale/corp#14480
Signed-off-by: Maisem Ali <maisem@tailscale.com>
This PR adds a SessionID field to the ipn.Notify struct so that
ipn buses can identify a session and register deferred clean up
code in the future. The first use case this is for is to be able to
tie foreground serve configs to a specific watch session and ensure
its clean up when a connection is closed.
Updates #8489
Signed-off-by: Marwan Sulaiman <marwan@tailscale.com>
If Start was called multiple times concurrently, it would
create a new client and shutdown the previous one. However
there was a race possible between shutting down the old one
and assigning a new one where the concurent goroutine may
have assigned another one already and it would leak.
Updates tailscale/corp#14471
Signed-off-by: Maisem Ali <maisem@tailscale.com>
resetControlClientLocked is called while b.mu was held and
would call cc.Shutdown which would wait for the observer queue
to drain.
However, there may be active callbacks from cc already waiting for
b.mu resulting in a deadlock.
This makes it so that resetControlClientLocked does not call
Shutdown, and instead just returns the value.
It also makes it so that any status received from previous cc
are ignored.
Updates tailscale/corp#12827
Signed-off-by: Maisem Ali <maisem@tailscale.com>
During Shutdown of an ephemeral node, we called Logout (to best effort
delete the node earlier), which then called back into
resetForProfileChangeLockedOnEntry, which then tried to Start
again. That's all a waste of work during shutdown and complicates
other cleanups coming later.
Updates #cleanup
Change-Id: I0b8648cac492fc70fa97c4ebef919bbe352c5d7b
Co-authored-by: Maisem Ali <maisem@tailscale.com>
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
We already removed the async API, make it more sync and remove
the FinishLogout state too.
This also makes the callback be synchronous again as the previous
attempt was trying to work around the logout callback resulting
in a client shutdown getting blocked forever.
Updates #3833
Signed-off-by: Maisem Ali <maisem@tailscale.com>
We have cases where the SetControlClientStatus would result in
a Shutdown call back into the auto client that would block
forever. The right thing to do here is to fix the LocalBackend
state machine but thats a different dumpster fire that we
are slowly making progress towards.
This makes it so that the SetControlClientStatus happens in a
different goroutine so that calls back into the auto client
do not block.
Also add a few missing mu.Unlocks in LocalBackend.Start.
Updates #9181
Signed-off-by: Maisem Ali <maisem@tailscale.com>
* don't try to re-Start (and thus create a new client) during Shutdown
* in tests, wait for controlclient to fully shut down when replacing it
* log a bit more
Updates tailscale/corp#14139
Updates tailscale/corp#13175 etc
Updates #9178 and its flakes.
Change-Id: I3ed2440644dc157aa6e616fe36fbd29a6056846c
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
They were entirely redundant and 1:1 with the status field
so this turns them into methods instead.
Updates #cleanup
Updates #1909
Change-Id: I7d939750749edf7dae4c97566bbeb99f2f75adbc
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
For now the method has only one interface (the same as the func it's
replacing) but it will grow, eventually with the goal to remove the
controlclient.Status type for most purposes.
Updates #1909
Change-Id: I715c8bf95e3f5943055a94e76af98d988558a2f2
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Upcoming work on incremental netmap change handling will require some
replumbing of which subsystems get notified about what. Done naively,
it could break "tailscale status --json" visibility later. To make sure
I understood the flow of all the updates I was rereading the status code
and realized parts of ipnstate.Status were being populated by the wrong
subsystems.
The engine (wireguard) and magicsock (data plane, NAT traveral) should
only populate the stuff that they uniquely know. The WireGuard bits
were fine but magicsock was populating stuff stuff that LocalBackend
could've better handled, so move it there.
Updates #1909
Change-Id: I6d1b95d19a2d1b70fbb3c875fac8ea1e169e8cb0
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
It was in SelfNode.Hostinfo anyway. The redundant copy was just
costing us an allocation per netmap (a Hostinfo.Clone).
Updates #1909
Change-Id: Ifac568aa5f8054d9419828489442a0f4559bc099
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Adds ability to start Funnel in the foreground and stream incoming
connections. When foreground process is stopped, Funnel is turned
back off for the port.
Exampe usage:
```
TAILSCALE_FUNNEL_V2=on tailscale funnel 8080
```
Updates #8489
Signed-off-by: Marwan Sulaiman <marwan@tailscale.com>
And optimize the Persist setting a bit, allocating later and only mutating
fields when there's been a Node change.
Updates #1909
Change-Id: Iaddfd9e88ef76e1d18e8d0a41926eb44d0955312
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
In b987b2ab18 (2021-01-12) when we introduced sharing we mapped
the sharer to the userid at a low layer, mostly to fix the display of
"tailscale status" and the client UIs, but also some tests.
The commit earlier today, 7dec09d169, removed the 2.5yo option
to let clients disable that automatic mapping, as clearly we were never
getting around to it.
This plumbs the Sharer UserID all the way to ipnstatus so the CLI
itself can choose to print out the Sharer's identity over the node's
original owner.
Then we stop mangling Node.User and let clients decide how they want
to render things.
To ease the migration for the Windows GUI (which currently operates on
tailcfg.Node via the NetMap from WatchIPNBus, instead of PeerStatus),
a new method Node.SharerOrUser is added to do the mapping of
Sharer-else-User.
Updates #1909
Updates tailscale/corp#1183
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Make it just a views.Slice[netip.Prefix] instead of its own named type.
Having the special case led to circular dependencies in another WIP PR
of mine.
Updates #8948
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Now a nodeAttr: ForceBackgroundSTUN, DERPRoute, TrimWGConfig,
DisableSubnetsIfPAC, DisableUPnP.
Kept support for, but also now a NodeAttr: RandomizeClientPort.
Removed: SetForceBackgroundSTUN, SetRandomizeClientPort (both never
used, sadly... never got around to them. But nodeAttrs are better
anyway), EnableSilentDisco (will be a nodeAttr later when that effort
resumes).
Updates #8923
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
It was being modified in two places in Direct for the auth routine
and then in LocalBackend when a new NetMap was received. This was
confusing, so make Direct also own changes to Persist when a new
NetMap is received.
Updates #7726
Signed-off-by: Maisem Ali <maisem@tailscale.com>
This adds the capability to pad disco ping message payloads to reach a
specified size. It also plumbs it through to the tailscale ping -size
flag.
Disco pings used for actual endpoint discovery do not use this yet.
Updates #311.
Signed-off-by: salman <salman@tailscale.com>
Co-authored-by: Val <valerie@tailscale.com>
Rather than make each ipn.StateStore implementation guard against
useless writes (a write of the same value that's already in the
store), do writes via a new wrapper that has a fast path for the
unchanged case.
This then fixes profileManager's flood of useless writes to AWS SSM,
etc.
Updates #8785
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
This change introduces a new subcommand, `exit-node`, along with a
subsubcommand of `list` and a `--filter` flag.
Exit nodes without location data will continue to be displayed when
`status` is used. Exit nodes with location data will only be displayed
behind `exit-node list`, and in status if they are the active exit node.
The `filter` flag can be used to filter exit nodes with location data by
country.
Exit nodes with Location.Priority data will have only the highest
priority option for each country and city listed. For countries with
multiple cities, a <Country> <Any> option will be displayed, indicating
the highest priority node within that country.
Updates tailscale/corp#13025
Signed-off-by: Charlotte Brandhorst-Satzkorn <charlotte@tailscale.com>
Define PeerCapabilty and PeerCapMap as the new way of sending down
inter-peer capability information.
Previously, this was unstructured and you could only send down strings
which got too limiting for certain usecases. Instead add the ability
to send down raw JSON messages that are opaque to Tailscale but provide
the applications to define them however they wish.
Also update accessors to use the new values.
Updates #4217
Signed-off-by: Maisem Ali <maisem@tailscale.com>
The server hasn't sent it in ages.
Updates #cleanup
Change-Id: I9695ab0f074ec6fb006e11faf3cdfc5ca049fbf8
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
