Also fix a somewhat related printing bug in the process where
some paths would print "Success." inconsistently even
when there otherwise was no output (in the EditPrefs path)
Fixes#3830
Updates #3702 (which broke it once while trying to fix it)
Change-Id: Ic51e14526ad75be61ba00084670aa6a98221daa5
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Now that Go 1.17 has module graph pruning
(https://go.dev/doc/go1.17#go-command), we should be able to use
upstream netstack without breaking our private repo's build
that then depends on the tailscale.com Go module.
This is that experiment.
Updates #1518 (the original bug to break out netstack to own module)
Updates #2642 (this updates netstack, but doesn't remove workaround)
Change-Id: I27a252c74a517053462e5250db09f379de8ac8ff
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
So Linux/etc CLI users get helpful advice to run tailscale
with --operator=$USER when they try to 'tailscale file {cp,get}'
but are mysteriously forbidden.
Signed-off-by: David Eger <eger@google.com>
Signed-off-by: David Eger <david.eger@gmail.com>
Disabled by default.
To use, run tailscaled with:
TS_SSH_ALLOW_LOGIN=you@bar.com
And enable with:
$ TAILSCALE_USE_WIP_CODE=true tailscale up --ssh=true
Then ssh [any-user]@[your-tailscale-ip] for a root bash shell.
(both the "root" and "bash" part are temporary)
Updates #3802
Change-Id: I268f8c3c95c8eed5f3231d712a5dc89615a406f0
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>
Surveying the fleet prior to turning off old/unused/insecure
TLS versions.
Updates tailscale/corp#3615
Signed-off-by: David Anderson <danderson@tailscale.com>
The GitHub code scanner flagged this as a security vulnerability.
I don't believe it was, but I couldn't convince myself of it 100%.
Err on the safe side and use html/template to generate the HTML,
with all necessary escaping.
Fixestailscale/corp#2698
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
The --reset shouldn't imply that a Backend.Start is necessary. With
this, it can do a Backend.EditPrefs instead, which then doesn't do all
the heavy work that Start does. Also, Start on Windows behaves
slightly differently than Linux etc in some cases because of tailscaled
running in client mode on Windows (where the GUI supplies the prefs).
Fixes#3702
Change-Id: I75c9f08d5e0052bf623074030a3a7fcaa677abf6
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
I apparently only did HTTP before, not HTTPS.
Updates tailscale/corp#1327
Change-Id: I7d5265a0a25fcab5b142c8c3f21a0920f6cae39f
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
But still support hello.ipn.dev for a bit.
Updates tailscale/corp#1327
Change-Id: Iab59cca0b260d69858af16f4e42677e54f9fe54a
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Treat UDP send EPERM errors as a lost UDP packet, not something super
fatal. That's just the Linux firewall preventing it from going out.
And add a leaf package net/neterror for that (and future) policy that
all three packages can share, with tests.
Updates #3619
Change-Id: Ibdb838c43ee9efe70f4f25f7fc7fdf4607ba9c1d
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
This is for use by the Windows GUI client to log via when an
exit node is in use, so the logs don't go out via the exit node and
instead go directly, like tailscaled's. The dialer tried to do that
in the unprivileged GUI by binding to a specific interface, but the
"Internet Kill Switch" installed by tailscaled for exit nodes
precludes that from working and instead the GUI fails to dial out.
So, go through tailscaled (with a CONNECT request) instead.
Fixestailscale/corp#3169
Change-Id: I17a8efdc1d4b8fed53a29d1c19995592b651b215
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
This moves the Windows-only initialization of the filelogger into
logpolicy. Previously we only did it when babysitting the tailscaled
subprocess, but this meant that log messages from the service itself
never made it to disk. Examples that weren't logged to disk:
* logtail unable to dial out,
* DNS flush messages from the service
* svc.ChangeRequest messages (#3581)
This is basically the same fix as #3571 but staying in the Logf type,
and avoiding build-tagged file (which wasn't quite a goal, but
happened and seemed nice)
Fixes#3570
Co-authored-by: Aaron Klotz <aaron@tailscale.com>
Change-Id: Iacd80c4720b7218365ec80ae143339d030842702
I broke it in 1.17.x sometime while rewiring some logs stuff,
mostly in 0653efb092 (but with a handful
of logs-related changes around that time)
Fixestailscale/corp#3265
Change-Id: Icb5c07412dc6d55f1d9244c5d0b51dceca6a7e34
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
One of the most annoying parts of using the Tailscale CLI on Windows
and the macOS GUI is that Tailscale's GUIs default to running with
"Route All" (accept all non-exitnode subnet routes) but the CLI--being
originally for Linux--uses the Linux default, which is to not accept
subnets.
Which means if a Windows user does, e.g.:
tailscale up --advertise-exit-node
Or:
tailscale up --shields-up
... then it'd warn about reverting the --accept-routes option, which the user
never explicitly used.
Instead, make the CLI's default match the platform/GUI's default.
Change-Id: I15c804b3d9b0266e9ca8651e0c09da0f96c9ef8d
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
fee2d9fad added support for cmd/tailscale to connect to IPNExtension.
It came in two parts: If no socket was provided, dial IPNExtension first,
and also, if dialing the socket failed, fall back to IPNExtension.
The second half of that support caused the integration tests to fail
when run on a machine that was also running IPNExtension.
The integration tests want to wait until the tailscaled instances
that they spun up are listening. They do that by dialing the new
instance. But when that dial failed, it was falling back to IPNExtension,
so it appeared (incorrectly) that tailscaled was running.
Hilarity predictably ensued.
If a user (or a test) explicitly provides a socket to dial,
it is a reasonable assumption that they have a specific tailscaled
in mind and don't want to fall back to IPNExtension.
It is certainly true of the integration tests.
Instead of adding a bool to Connect, split out the notion of a
connection strategy. For now, the implementation remains the same,
but with the details hidden a bit. Later, we can improve that.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
This is enough to handle the DNS queries as generated by Go's
net package (which our HTTP/SOCKS client uses), and the responses
generated by the ExitDNS DoH server.
This isn't yet suitable for putting on 100.100.100.100 where a number
of different DNS clients would hit it, as this doesn't yet do
EDNS0. It might work, but it's untested and likely incomplete.
Likewise, this doesn't handle anything about truncation, as the
exchanges are entirely in memory between Go or DoH. That would also
need to be handled later, if/when it's hooked up to 100.100.100.100.
Updates #3507
Change-Id: I1736b0ad31eea85ea853b310c52c5e6bf65c6e2a
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
The caller of func run said:
// No need to log; the func already did
But that wasn't true. Some return paths didn't log.
So instead, return rich errors and have func main do the logging,
so we can't miss anything in the future.
Prior to this, safesocket.Listen for instance was causing tailscaled
to os.Exit(1) on failure without any clue as to why.
Change-Id: I9d71cc4d73d0fed4aa1b1902cae199f584f25793
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
To make ExitDNS cheaper.
Might not finish client-side support in December before 1.20, but at
least server support can start rolling out ahead of clients being
ready for it.
Tested with curl against peerapi.
Updates #1713
Change-Id: I676fed5fb1aef67e78c542a3bc93bddd04dd11fe
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
And simplify, unexport some tsdial/netstack stuff in the the process.
Fixes#3475
Change-Id: I186a5a5cbd8958e25c075b4676f7f6e70f3ff76e
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Before:
failed to connect to local tailscaled (which appears to be running). Got error: Get "http://local-tailscaled.sock/localapi/v0/status": EOF
After:
failed to connect to local tailscaled (which appears to be running as IPNExtension, pid 2118). Got error: Get "http://local-tailscaled.sock/localapi/v0/status": EOF
This was useful just now, as it made it clear that tailscaled I thought
I was connecting to might not in fact be running; there was
a second tailscaled running that made the error message slightly misleading.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
It was using the wrong prefs (intended vs current) to map the current
exit node ID to an IP.
Fixes#3480
Change-Id: I9f117d99a84edddb4cd1cb0df44a2f486abde6c2
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
If you're online, let tailscale up --exit-node=NAME map NAME to its IP.
We don't store the exit node name server-side in prefs, avoiding
the concern raised earlier.
Fixes#3062
Change-Id: Ieea5ceec1a30befc67e9d6b8a530b3cb047b6b40
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
This starts to refactor tsdial.Dialer's name resolution to have
different stages: in-memory MagicDNS vs system resolution. A future
change will plug in ExitDNS resolution.
This also plumbs a Dialer into netstack and unexports the dnsMap
internals.
And it removes some of the async AddNetworkMapCallback usage and
replaces it with synchronous updates of the Dialer's netmap
from LocalBackend, since the LocalBackend has the Dialer too.
Updates #3475
Change-Id: Idcb7b1169878c74f0522f5151031ccbc49fe4cb4
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
In prep for moving stuff out of LocalBackend.
Change-Id: I9725aa9c3ebc7275f8c40e040b326483c0340127
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Not done yet, but this move more of the outbound dial special casing
from random packages into tsdial, which aspires to be the one unified
place for all outbound dialing shenanigans.
Then this plumbs it all around, so everybody is ultimately
holding on to the same dialer.
As of this commit, macOS/iOS using an exit node should be able to
reach to the exit node's DoH DNS proxy over peerapi, doing the sockopt
to stay within the Network Extension.
A number of steps remain, including but limited to:
* move a bunch more random dialing stuff
* make netstack-mode tailscaled be able to use exit node's DNS proxy,
teaching tsdial's resolver to use it when an exit node is in use.
Updates #1713
Change-Id: I1e8ee378f125421c2b816f47bc2c6d913ddcd2f5
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
For now this just deletes the net/socks5/tssocks implementation (and
the DNSMap stuff from wgengine/netstack) and moves it into net/tsdial.
Then initialize a Dialer early in tailscaled, currently only use for the
outbound and SOCKS5 proxies. It will be plumbed more later. Notably, it
needs to get down into the DNS forwarder for exit node DNS forwading
in netstack mode. But it will also absorb all the peerapi setsockopt
and netns Dial and tlsdial complexity too.
Updates #1713
Change-Id: Ibc6d56ae21a22655b2fa1002d8fc3f2b2ae8b6df
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
So Taildrop sends work even if the local tailscaled is running in
netstack mode, as it often is on Synology, etc.
Updates #2179 (which is primarily about receiving, but both important)
Change-Id: I9bd1afdc8d25717e0ab6802c7cf2f5e0bd89a3b2
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
It's a basic "deny everything" policy, since DERP's HTTP
server is very uninteresting from a browser POV. But it
stops every security scanner under the sun from reporting
"dangerously configured" HTTP servers.
Updates tailscale/corp#3119
Signed-off-by: David Anderson <danderson@tailscale.com>
When this happens, it is incredibly noisy in the logs.
It accounts for about a third of all remaining
"unexpected" log lines from a recent investigation.
It's not clear that we know how to fix this,
we have a functioning workaround,
and we now have a (cheap and efficient) metric for this
that we can use for measurements.
So reduce the logging to approximately once per minute.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
This limits the output to a single IP address.
RELNOTE=tailscale ip now has a -1 flag (TODO: update docs to use it)
Fixes#1921
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
We replace the cmd.exe invocation with RtlGetNtVersionNumbers for the first
three fields. On Windows 10+, we query for the fourth field which is available
via the registry.
The fourth field is not really documented anywhere; Firefox has been querying
it successfully since Windows 10 was released, so we can be pretty confident in
its longevity at this point.
Fixes https://github.com/tailscale/tailscale/issues/1478
Signed-off-by: Aaron Klotz <aaron@tailscale.com>
wgengine/wgcfg: introduce wgcfg.NewDevice helper to disable roaming
at all call sites (one real plus several tests).
Fixestailscale/corp#3016.
Signed-off-by: David Anderson <danderson@tailscale.com>
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
It was a mess of flags. Use subcommands under "debug" instead.
And document loudly that it's not a stable interface.
Change-Id: Idcc58f6a6cff51f72cb5565aa977ac0cc30c3a03
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
And annotate magicsock as a start.
And add localapi and debug handlers with the Prometheus-format
exporter.
Updates #3307
Change-Id: I47c5d535fe54424741df143d052760387248f8d3
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
More work towards removing the massive ipnserver.Run and ipnserver.Options
and making composable pieces.
Work remains. (The getEngine retry loop on Windows complicates things.)
For now some duplicate code exists. Once the Windows side is fixed
to either not need the retry loop or to move the retry loop into a
custom wgengine.Engine wrapper, then we can unify tailscaled_windows.go
too.
Change-Id: If84d16e3cd15b54ead3c3bb301f27ae78d055f80
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>
Using temporary netlink fork in github.com/tailscale/netlink until we
get the necessary changes upstream in either vishvananda/netlink
or jsimonetti/rtnetlink.
Updates #391
Change-Id: I6e1de96cf0750ccba53dabff670aca0c56dffb7c
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Even if not in use. We plan to use it for more stuff later.
(not for iOS or macOS-GUIs yet; only tailscaled)
Change-Id: Idaef719d2a009be6a39f158fd8f57f8cca68e0ee
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Temporary measure until we switch to Go 1.18.
$ go run ./cmd/tailscale version
1.17.0-date.20211022
go version: go1.17
Updates #81
Change-Id: Ic82ebffa5f46789089e5fb9810b3f29e36a47f1a
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
So js/wasm can override where those go, without implementing
an *os.File pipe pair, etc.
Updates #3157
Change-Id: I14ba954d9f2349ff15b58796d95ecb1367e8ba3a
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
And the derper change to add a CORS endpoint for latency measurement.
And a little magicsock change to cut down some log spam on js/wasm.
Updates #3157
Change-Id: I5fd9e6f5098c815116ddc8ac90cbcd0602098a48
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
utils/winutil/vss contains just enough COM wrapping to query the Volume Shadow Copy service for snapshots.
WalkSnapshotsForLegacyStateDir is the friendlier interface that adds awareness of our actual use case,
mapping the snapshots and locating our legacy state directory.
Updates #3011
Signed-off-by: Aaron Klotz <aaron@tailscale.com>
The "go generate" command blindly looks for "//go:generate" anywhere
in the file regardless of whether it is truly a comment.
Prevent this false positive in cloner.go by mangling the string
to look less like "//go:generate".
Signed-off-by: Joe Tsai <joetsai@digital-static.net>
Emit a go:generate pragma with the full set of flags passed to cloner.
This allows the user to simply run "go generate" at the location
of the generate file to reproduce the file.
Signed-off-by: Joe Tsai <joetsai@digital-static.net>
From https://github.com/tailscale/tailscale/pull/1919 with
edits by bradfitz@.
This change introduces a new storage provider for the state file. It
allows users to leverage AWS SSM parameter store natively within
tailscaled, like:
$ tailscaled --state=arn:aws:ssm:eu-west-1:123456789:parameter/foo
Known limitations:
- it is not currently possible to specific a custom KMS key ID
RELNOTE=tailscaled on Linux supports using AWS SSM for state
Edits-By: Brad Fitzpatrick <bradfitz@tailscale.com>
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Signed-off-by: Maxime VISONNEAU <maxime.visonneau@gmail.com>
This feature wasn't working until I realized that we also need to opt into
the events. MSDN wasn't so generous as to make this easy to deduce.
Updates #2956
Signed-off-by: Aaron Klotz <aaron@tailscale.com>
A couple of gnarly assumptions in this code, as always with the async
message thing.
UI button is based on the DNS settings in the admin panel.
Co-authored-by: Maisem Ali <maisem@tailscale.com>
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
Lot of people have been hitting this.
Now it says:
$ tailscale cert tsdev.corp.ts.net
Access denied: cert access denied
Use 'sudo tailscale cert' or 'tailscale up --operator=$USER' to not require root.
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
The old name invited confusion:
* is this the HTTP proxy to use ourselves? (no, that's
via an environment variable, per proxy conventions)
* is this for LetsEncrypt https-to-localhost-http
proxying? (no, that'll come later)
So rename to super verbose --outbound-http-proxy-listen
before the 1.16.0 release to make it clear what it is.
It listens (serves) and it's for outbound, not inbound.
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
For the service, all we need to do is handle the `svc.SessionChange` command.
Upon receipt of a `windows.WTS_SESSION_UNLOCK` event, we fire off a goroutine to flush the DNS cache.
(Windows expects responses to service requests to be quick, so we don't want to do that synchronously.)
This is gated on an integral registry value named `FlushDNSOnSessionUnlock`,
whose value we obtain during service initialization.
(See [this link](https://docs.microsoft.com/en-us/windows/win32/api/winsvc/nc-winsvc-lphandler_function_ex) for information re: handling `SERVICE_CONTROL_SESSIONCHANGE`.)
Fixes#2956
Signed-off-by: Aaron Klotz <aaron@tailscale.com>
This adds support for tailscaled to be an HTTP proxy server.
It shares the same backend dialing code as the SOCK5 server, but the
client protocol is HTTP (including CONNECT), rather than SOCKS.
Fixes#2289
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Because the macOS CLI runs in the sandbox, including the filesystem,
so users would be confused that -cpu-profile=prof.cpu succeeds but doesn't
write to their current directory, but rather in some random Library/Containers
directory somewhere on the machine (which varies depending on the Mac build
type: App Store vs System Extension)
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
This was already possible on Linux if you ran tailscaled with --debug
(which runs net/http/pprof), but it requires the user have the Go
toolchain around.
Also, it wasn't possible on macOS, as there's no way to run the IPNExtension
with a debug server (it doesn't run tailscaled).
And on Windows it's super tedious: beyond what users want to do or
what we want to explain.
Instead, put it in "tailscale debug" so it works and works the same on
all platforms. Then we can ask users to run it when we're debugging something
and they can email us the output files.
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
pfSense stores its SSL certificate and key in the PHP config.
We wrote PHP code to pull the two out of the PHP config and
into environment variables before running "tailscale web".
The pfSense web UI is served over https, we need "tailscale web"
to also support https in order to put it in an <iframe>.
Signed-off-by: Denton Gentry <dgentry@tailscale.com>
There are two reasons this can't ever go to actual logs,
but rewrite it to make it happy.
Fixestailscale/corp#2695
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
ProgramData has a permissive ACL. For us to safely store machine-wide
state information, we must set a more restrictive ACL on our state directory.
We set the ACL so that only talescaled's user (ie, LocalSystem) and the
Administrators group may access our directory.
We must include Administrators to ensure that logs continue to be easily
accessible; omitting that group would force users to use special tools to
log in interactively as LocalSystem, which is not ideal.
(Note that the ACL we apply matches the ACL that was used for LocalSystem's
AppData\Local).
There are two cases where we need to reset perms: One is during migration
from the old location to the new. The second case is for clean installations
where we are creating the file store for the first time.
Updates #2856
Signed-off-by: Aaron Klotz <aaron@tailscale.com>
The fully qualified name of the type is thisPkg.tname,
so write the args like that too.
Suggested-by: Joe Tsai <joetsai@digital-static.net>
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
And in the process, fix a bug:
The fmt formatting was being applied by writef,
not fmt.Sprintf, thus emitting a MISSING string.
And there's no guarantee that fmt will be imported
in the generated code.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
Change from a single-case type switch to a type assertion
with an early return.
That exposes that the name arg to gen is unneeded.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
This is a package for shared utilities used in doing codegen programs.
The inaugural API is for writing gofmt'd code to a file.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
Spelling out the command to run for every type
means that changing the command makes for a large, repetitive diff.
Stop doing that.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
Real goal is to eliminate some allocs in the STUN path, but that requires
work in the standard library.
See comments in #2783.
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
The earlier 382b349c54 was too late,
as engine creation itself needed to listen on things.
Fixes#2827
Updates #2822
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Add a mode control for derp server, and add a "manual" mode
to get derp server certificate. Under manual mode, certificate
is searched in the directory given by "--cert-dir". Certificate
should in PEM format, and use "hostname.{key,crt}" as filename.
If no hostname is used, search by the hostname given for listen.
Fixes#2794
Signed-off-by: SilverBut <SilverBut@users.noreply.github.com>
And in the process, fix the related confusing error messages from
pinging your own IP or hostname.
Fixes#2803
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
* Revert "Revert "types/key: add MachinePrivate and MachinePublic.""
This reverts commit 61c3b98a24.
Signed-off-by: David Anderson <danderson@tailscale.com>
* types/key: add ControlPrivate, with custom serialization.
ControlPrivate is just a MachinePrivate that serializes differently
in JSON, to be compatible with how the Tailscale control plane
historically serialized its private key.
Signed-off-by: David Anderson <danderson@tailscale.com>
Plumb throughout the codebase as a replacement for the mixed use of
tailcfg.MachineKey and wgkey.Private/Public.
Signed-off-by: David Anderson <danderson@tailscale.com>