Commit Graph

371 Commits (ddd85b9d91ebf3d7905f506afe46d50eee740fbb)

Author SHA1 Message Date
Josh Bleecher Snyder ddd85b9d91 wgengine/magicsock: rename discoEndpoint.wgEndpointHostPort to wgEndpoint
Fields rename only.

Part of the general effort to make our code agnostic about endpoint formatting.
It's just a name, but it will soon be a misleading one; be more generic.
Do this as a separate commit because it generates a lot of whitespace changes.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
4 years ago
Josh Bleecher Snyder e0bd3cc70c wgengine/magicsock: use netaddr.MustParseIPPrefix
Delete our bespoke helper.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
4 years ago
Josh Bleecher Snyder bc68e22c5b all: s/CreateEndpoint/ParseEndpoint/ in docs
Upstream wireguard-go renamed the interface method
from CreateEndpoint to ParseEndpoint.
I missed some comments. Fix them.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
4 years ago
Josh Bleecher Snyder a0dacba877 wgengine/magicsock: simplify legacy endpoint DstToString
Legacy endpoints (addrSet) currently reconstruct their dst string when requested.

Instead, store the dst string we were given to begin with.
In addition to being simpler and cheaper, this makes less code
aware of how to interpret endpoint strings.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
4 years ago
Josh Bleecher Snyder 64047815b0 wgenengine/magicsock: delete cursed tests
Signed-off-by: Josh Bleecher Snyder <josharian@gmail.com>
4 years ago
Josh Bleecher Snyder 7ee891f5fd all: delete wgcfg.Key and wgcfg.PrivateKey
For historical reasons, we ended up with two near-duplicate
copies of curve25519 key types, one in the wireguard-go module
(wgcfg) and one in the tailscale module (types/wgkey).
Then we moved wgcfg to the tailscale module.
We can now remove the wgcfg key type in favor of wgkey.

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

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

Signed-off-by: Josh Bleecher Snyder <josharian@gmail.com>
4 years ago
Josh Bleecher Snyder fe50ded95c health: track whether we have a functional udp4 bind
Suggested-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Signed-off-by: Josh Bleecher Snyder <josharian@gmail.com>
4 years ago
Josh Bleecher Snyder 7dc7078d96 wgengine/magicsock: use netaddr.IP in listenPacket
It must be an IP address; enforce that at the type level.

Suggested-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Signed-off-by: Josh Bleecher Snyder <josharian@gmail.com>
4 years ago
Josh Bleecher Snyder 3c543c103a wgengine/magicsock: unify initial bind and rebind
We had two separate code paths for the initial UDP listener bind
and any subsequent rebinds.

IPv6 got left out of the rebind code.
Rather than duplicate it there, unify the two code paths.
Then improve the resulting code:

* Rebind had nested listen attempts to try the user-specified port first,
  and then fall back to :0 if that failed. Convert that into a loop.
* Initial bind tried only the user-specified port.
  Rebind tried the user-specified port and 0.
  But there are actually three ports of interest:
  The one the user specified, the most recent port in use, and 0.
  We now try all three in order, as appropriate.
* In the extremely rare case in which binding to port 0 fails,
  use a dummy net.PacketConn whose reads block until close.
  This will keep the wireguard-go receive func goroutine alive.

As a pleasant side-effect of this, if we decide that
we need to resuscitate #1796, it will now be much easier.

Fixes #1799

Co-authored-by: David Anderson <danderson@tailscale.com>
Signed-off-by: Josh Bleecher Snyder <josharian@gmail.com>
4 years ago
Josh Bleecher Snyder 8fb66e20a4 wgengine/magicsock: remove DefaultPort const
Assume it'll stay at 0 forever, so hard-code it
and delete code conditional on it being non-0.

Signed-off-by: Josh Bleecher Snyder <josharian@gmail.com>
4 years ago
Josh Bleecher Snyder a8f61969b9 wgengine/magicsock: remove context arg from listenPacket
It was set to context.Background by all callers, for the same reasons.
Set it locally instead, to simplify call sites.

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

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

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

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

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

Updates #1790

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

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

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

Fixes #1781

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

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

Signed-off-by: Josh Bleecher Snyder <josharian@gmail.com>
4 years ago
Josh Bleecher Snyder f845aae761 health: track whether magicsock receive functions are running
Signed-off-by: Josh Bleecher Snyder <josharian@gmail.com>
4 years ago
Josh Bleecher Snyder 48e30bb8de wgengine/magicsock: remove named return
Doesn't add anything.

Signed-off-by: Josh Bleecher Snyder <josharian@gmail.com>
4 years ago
Josh Bleecher Snyder a2a2c0ce1c wgengine/magicsock: fix two comments
Signed-off-by: Josh Bleecher Snyder <josharian@gmail.com>
4 years ago
Josh Bleecher Snyder b1e624ef04 wgengine/magicsock: remove unnecessary type assertions
Signed-off-by: Josh Bleecher Snyder <josharian@gmail.com>
4 years ago
Josh Bleecher Snyder 98714e784b wgengine/magicsock: improve Rebind logging
We were accidentally logging oldPort -> oldPort.

Log oldPort as well as c.port; if we failed to get the preferred port
in a previous rebind, oldPort might differ from c.port.

Signed-off-by: Josh Bleecher Snyder <josharian@gmail.com>
4 years ago
Josh Bleecher Snyder 15ceacc4c5 wgengine/magicsock: accept a host and port instead of an addr in listenPacket
This simplifies call sites and prevents accidental failure to use net.JoinHostPort.

Signed-off-by: Josh Bleecher Snyder <josharian@gmail.com>
4 years ago
Brad Fitzpatrick b993d9802a ipn/ipnlocal, etc: require file sharing capability to send/recv files
tailscale/corp#1582

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
4 years ago
Brad Fitzpatrick 762180595d ipn/ipnstate: add PeerStatus.TailscaleIPs slice, deprecate TailAddr
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
4 years ago
Brad Fitzpatrick 34d2f5a3d9 tailcfg: add Endpoint, EndpointType, MapRequest.EndpointType
Track endpoints internally with a new tailcfg.Endpoint type that
includes a typed netaddr.IPPort (instead of just a string) and
includes a type for how that endpoint was discovered (STUN, local,
etc).

Use []tailcfg.Endpoint instead of []string internally.

At the last second, send it to the control server as the existing
[]string for endpoints, but also include a new parallel
MapRequest.EndpointType []tailcfg.EndpointType, so the control server
can start filtering out less-important endpoint changes from
new-enough clients. Notably, STUN-discovered endpoints can be filtered
out from 1.6+ clients, as they can discover them amongst each other
via CallMeMaybe disco exchanges started over DERP. And STUN endpoints
change a lot, causing a lot of MapResposne updates. But portmapped
endpoints are worth keeping for now, as they they work right away
without requiring the firewall traversal extra RTT dance.

End result will be less control->client bandwidth. (despite negligible
increase in client->control bandwidth)

Updates tailscale/corp#1543

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
4 years ago
Josh Bleecher Snyder ba72126b72 wgengine/magicsock: remove RebindingUDPConn.FakeClosed
It existed to work around the frequent opening and closing
of the conn.Bind done by wireguard-go.
The preceding commit removed that behavior,
so we can simply close the connections
when we are done with them.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
4 years ago
Josh Bleecher Snyder 69cdc30c6d wgengine/wgcfg: remove Config.ListenPort
We don't use the port that wireguard-go passes to us (via magicsock.connBind.Open).
We ignore it entirely and use the port we selected.

When we tell wireguard-go that we're changing the listen_port,
it calls connBind.Close and then connBind.Open.
And in the meantime, it stops calling the receive functions,
which means that we stop receiving and processing UDP and DERP packets.
And that is Very Bad.

That was never a problem prior to b3ceca1dd7,
because we passed the SkipBindUpdate flag to our wireguard-go fork,
which told wireguard-go not to re-bind on listen_port changes.
That commit eliminated the SkipBindUpdate flag.

We could write a bunch of code to work around the gap.
We could add background readers that process UDP and DERP packets when wireguard-go isn't.
But it's simpler to never create the conditions in which wireguard-go rebinds.

The other scenario in which wireguard-go re-binds is device.Down.
Conveniently, we never call device.Down. We go from device.Up to device.Close,
and the latter only when we're shutting down a magicsock.Conn completely.

Rubber-ducked-by: Avery Pennarun <apenwarr@tailscale.com>
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
4 years ago
Josh Bleecher Snyder b3ceca1dd7 wgengine/...: split into multiple receive functions
Upstream wireguard-go has changed its receive model.
NewDevice now accepts a conn.Bind interface.

The conn.Bind is stateless; magicsock.Conns are stateful.
To work around this, we add a connBind type that supports
cheap teardown and bring-up, backed by a Conn.

The new conn.Bind allows us to specify a set of receive functions,
rather than having to shoehorn everything into ReceiveIPv4 and ReceiveIPv6.
This lets us plumbing DERP messages directly into wireguard-go,
instead of having to mux them via ReceiveIPv4.

One consequence of the new conn.Bind layer is that
closing the wireguard-go device is now indistinguishable
from the routine bring-up and tear-down normally experienced
by a conn.Bind. We thus have to explicitly close the magicsock.Conn
when the close the wireguard-go device.

One downside of this change is that we are reliant on wireguard-go
to call receiveDERP to process DERP messages. This is fine for now,
but is perhaps something we should fix in the future.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
4 years ago
Josh Bleecher Snyder 34d4943357 all: gofmt -s
The code is not obviously better or worse, but this makes the little warning
triangle in my editor go away, and the distraction removal is worth it.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
4 years ago
Josh Bleecher Snyder 1df162b05b wgengine/magicsock: adapt CreateEndpoint signature to match wireguard-go
Part of a temporary change to make merging wireguard-go easier.
See https://github.com/tailscale/wireguard-go/pull/45.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
4 years ago
Josh Bleecher Snyder 36a85e1760 wgengine/magicsock: don't call t.Fatal in magicStack.IP
It can end up executing an a new goroutine,
at which point instead of immediately stopping test execution, it hangs.
Since this is unexpected anyway, panic instead.
As a bonus, it makes call sites nicer and removes a kludge comment.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
4 years ago
David Anderson 016de16b2e net/tstun: rename TUN to Wrapper.
The tstun packagen contains both constructors for generic tun
Devices, and a wrapper that provides additional functionality.

Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
David Anderson 588b70f468 net/tstun: merge in wgengine/tstun.
Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
Brad Fitzpatrick 81143b6d9a ipn/ipnlocal: start of peerapi between nodes
Also some necessary refactoring of the ipn/ipnstate too.

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
4 years ago
Josh Bleecher Snyder 28af46fb3b wgengine: pass logger as a separate arg to device.NewDevice
Adapt to minor API changes in wireguard-go.
And factor out device.DeviceOptions variables.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
4 years ago
Josh Bleecher Snyder 4b77eca2de wgengine/magicsock: check returned error in addTestEndpoint
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
4 years ago
Brad Fitzpatrick c99f260e40 wgengine/magicsock: prefer IPv6 transport if roughly equivalent latency
Fixes #1566

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
4 years ago
Brad Fitzpatrick 9643d8b34d wgengine/magicsock: add an addrLatency type to combine an IPPort+time.Duration
Updates #1566 (but no behavior changes as of this change)

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
4 years ago
Brad Fitzpatrick 0994a9f7c4 wgengine{,/magicsock}: fix, improve "tailscale ping" to default routes and subnets
e.g.

$ tailscale ping 1.1.1.1
exit node found but not enabled

$ tailscale ping 10.2.200.2
node "tsbfvlan2" found, but not using its 10.2.200.0/24 route

$ sudo tailscale  up --accept-routes
$ tailscale ping 10.2.200.2
pong from tsbfvlan2 (100.124.196.94) via 10.2.200.34:41641 in 1ms

$ tailscale ping mon.ts.tailscale.com
pong from monitoring (100.88.178.64) via DERP(sfo) in 83ms
pong from monitoring (100.88.178.64) via DERP(sfo) in 21ms
pong from monitoring (100.88.178.64) via [2604:a880:4:d1::37:d001]:41641 in 22ms

This necessarily moves code up from magicsock to wgengine, so we can
look at the actual wireguard config.

Fixes #1564

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
4 years ago
Brad Fitzpatrick 7e0d12e7cc wgengine/magicsock: don't update control if only endpoint order changes
Updates #1559

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
4 years ago
Brad Fitzpatrick 32562a82a9 wgengine/magicsock: annotate a few more disco logs as verbose
Fixes #1540

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
4 years ago
Brad Fitzpatrick c19ed37b0f wgengine/magicsock: mark some legacy debug log output as verbose
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
4 years ago
Brad Fitzpatrick ba8c6d0775 health, controlclient, ipn, magicsock: tell health package state of things
Not yet checking anything. Just plumbing states into the health package.

Updates #1505

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
4 years ago
Brad Fitzpatrick 44ab0acbdb net/portmapper, wgengine/monitor: cache gateway IP info until link changes
Cuts down allocs & CPU in steady state (on regular STUN probes) when network
is unchanging.

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
4 years ago
Brad Fitzpatrick c81814e4f8 derp{,/derphttp},magicsock: tell DERP server when ping acks can be expected
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
4 years ago
Brad Fitzpatrick c576fea60e wgengine/magicsock: delete unused WhoIs method that was moved elsewhere
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
4 years ago
Brad Fitzpatrick ef7bac2895 tailcfg, net/portmapper, wgengine/magicsock: add NetInfo.HavePortMap
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
4 years ago
Brad Fitzpatrick 79d8288f0a wgengine/magicsock, derp, derp/derphttp: respond to DERP server->client pings
No server support yet, but we want Tailscale 1.6 clients to be able to respond
to them when the server can do it.

Updates #1310

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
4 years ago
Brad Fitzpatrick 387e83c8fe wgengine/magicsock: fix Conn.Rebind race that let ErrClosed errors be read
There was a logical race where Conn.Rebind could acquire the
RebindingUDPConn mutex, close the connection, fail to rebind, release
the mutex, and then because the mutex was no longer held, ReceiveIPv4
wouldn't retry reads that failed with net.ErrClosed, letting that
error back to wireguard-go, which would then stop running that receive
IP goroutine.

Instead, keep the RebindingUDPConn mutex held for the entirety of the
replacement in all cases.

Updates tailscale/corp#1289

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
4 years ago
Brad Fitzpatrick c445e3d327 wgengine/magicsock: fix typo in comment 4 years ago