We had a long-standing bug in which our TUN events channel
was being received from simultaneously in two places.
The first is wireguard-go.
At wgengine/userspace.go:366, we pass e.tundev to wireguard-go,
which starts a goroutine (RoutineTUNEventReader)
that receives from that channel and uses events to adjust the MTU
and bring the device up/down.
At wgengine/userspace.go:374, we launch a goroutine that
receives from e.tundev, logs MTU changes, and triggers
state updates when up/down changes occur.
Events were getting delivered haphazardly between the two of them.
We don't really want wireguard-go to receive the up/down events;
we control the state of the device explicitly by calling device.Up.
And the userspace.go loop MTU logging duplicates logging that
wireguard-go does when it received MTU updates.
So this change splits the single TUN events channel into up/down
and other (aka MTU), and sends them to the parties that ought
to receive them.
I'm actually a bit surprised that this hasn't caused more visible trouble.
If a down event went to wireguard-go but the subsequent up event
went to userspace.go, we could end up with the wireguard-go device disappearing.
I believe that this may also (somewhat accidentally) be a fix for #1790.
Signed-off-by: Josh Bleecher Snyder <josharian@gmail.com>
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>
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>
The resolver still only supports a single upstream config, and
ipn/wgengine still have to split up the DNS config, but this moves
closer to unifying the DNS configs.
As a handy side-effect of the refactor, IPv6 MagicDNS records exist
now.
Signed-off-by: David Anderson <danderson@tailscale.com>
So we have a documented & tested way to check whether we're in
netstack mode. To be used by future commits.
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
For discovery when an explicit hostname/IP is known. We'll still
also send it via control for finding peers by a list.
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
"Fake" doesn't mean a lot any more, given that many components
of the engine can be faked out, including in valid production
configurations like userspace-networking.
Signed-off-by: David Anderson <danderson@tailscale.com>
This makes setup more explicit in prod codepaths, without
requiring a bunch of arguments or helpers for tests and
userspace mode.
Signed-off-by: David Anderson <danderson@tailscale.com>
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>
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>
The Engine.LinkChange method was recently removed in
e3df29d488 while misremembering how
Android's link state mechanism worked.
Rather than do some last minute rearchitecting of link state on
Android before Tailscale 1.6, restore the old Engine.LinkChange hook
for now so the Android client doesn't need any changes. But change how
it's implemented to instead inject an event into the link monitor.
Fixes#1427
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Gets it out of wgengine so the Engine isn't responsible for being a
callback registration hub for it.
This also removes the Engine.LinkChange method, as it's no longer
necessary. The monitor tells us about changes; it doesn't seem to
need any help. (Currently it was only used by Swift, but as of
14dc790137 we just do the same from Go)
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
And add a --socks5-server flag.
And fix a race in SOCKS5 replies where the response header was written
concurrently with the copy from the backend.
Co-authored with Naman Sood.
Updates #707
Updates #504
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Currently it assumes exactly 1 registered callback. This changes it to
support 0, 1, or more than 1.
This is a step towards plumbing wgengine/monitor into more places (and
moving some of wgengine's interface state fetching into monitor in a
later step)
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
This was in place because retrieved allowed_ips was very expensive.
Upstream changed the data structure to make them cheaper to compute.
This commit is an experiment to find out whether they're now cheap enough.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
And move a couple other types down into leafier packages.
Now cmd/tailscale doesn't bring in netlink, magicsock, wgengine, etc.
Fixes#1181
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
This is mostly code movement from the wireguard-go repo.
Most of the new wgcfg package corresponds to the wireguard-go wgcfg package.
wgengine/wgcfg/device{_test}.go was device/config{_test}.go.
There were substantive but simple changes to device_test.go to remove
internal package device references.
The API of device.Config (now wgcfg.DeviceConfig) grew an error return;
we previously logged the error and threw it away.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
Rewrite log lines on the fly, based on the set of known peers.
This enables us to use upstream wireguard-go logging,
but maintain the Tailscale-style peer public key identifiers
that the rest of our systems (and people) expect.
Fixes#1183
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
This eliminates a dependency on wgcfg.Endpoint,
as part of the effort to eliminate our wireguard-go fork.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
Not usefully functional yet (mostly a proof of concept), but getting
it submitted for some work @namansood is going to do atop this.
Updates #707
Updates #634
Updates #48
Updates #835
The log lines that wireguard-go prints as it starts
and stops its worker routines are mostly noise.
They also happen after other work is completed,
which causes failures in some of the log testing packages.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
This is a replacement for the key-related parts
of the wireguard-go wgcfg package.
This is almost a straight copy/paste from the wgcfg package.
I have slightly changed some of the exported functions and types
to avoid stutter, added and tweaked some comments,
and removed some now-unused code.
To avoid having wireguard-go depend on this new package,
wgcfg will keep its key types.
We translate into and out of those types at the last minute.
These few remaining uses will be eliminated alongside
the rest of the wgcfg package.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
Lazy wg configuration now triggers if a peer has only endpoint
addresses (/32 for IPv4, /128 for IPv6). Subnet routers still
trigger eager configuration to avoid the need for a CIDR match
in the hot packet path.
Signed-off-by: David Anderson <danderson@tailscale.com>
The packet filter still rejects all IPv6, but decodes enough from v6
packets to do something smarter in a followup.
name time/op
Decode/tcp4-8 28.8ns ± 2%
Decode/tcp6-8 20.6ns ± 1%
Decode/udp4-8 28.2ns ± 1%
Decode/udp6-8 20.0ns ± 6%
Decode/icmp4-8 21.7ns ± 2%
Decode/icmp6-8 14.1ns ± 2%
Decode/unknown-8 9.43ns ± 2%
Signed-off-by: David Anderson <danderson@tailscale.com>
There was a bug with the lazy wireguard config code where, if the
minimum set of peers to tell wireguard didn't change, we skipped
calling userspaceEngine.updateActivityMapsLocked which updated
the various data structures that matched incoming traffic to later
reconfigure the minimum config.
That meant if an idle peer restarted and changed discovery keys, we
skipped updating our maps of disco keys/IPs that would caused us to
lazily inflate the config for that peer later if/when it did send
traffic.
This function is only called in fake mode, which won't do anything more
with the packet after we respond to it anyway, so dropping it in the
prefilter is not necessary. And it's kinda semantically wrong: we did
not reject it, so telling the upper layer that it was rejected produces
an ugly error message.
Signed-off-by: Avery Pennarun <apenwarr@tailscale.com>
If no interfaces are up, calm down and stop spamming so much. It was
noticed as especially bad on Windows, but probably was bad
everywhere. I just have the best network conditions testing on a
Windows VM.
Updates #604
Otherwise when PAC server is down, we log, and each log entry is a new
HTTP request (from logtail) and a new GetProxyForURL call, which again
logs, non-stop. This is also nicer to the WinHTTP service.
Then also hook up link change notifications to the cache to reset it
if there's a chance the network might work sooner.
For now. Get it working again so it's not stuck on 0.98.
Subnet relay can come later.
Updates #451
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Start of making the IPN state machine react to link changes and down
its DNS & routes if necessary to unblock proxy resolution (e.g. for
transitioning from public to corp networks where the corp network has
mandatory proxies and WPAD PAC files that can't be resolved while
using the DNS/routes configured previously)
This change should be a no-op. Just some callback plumbing.
Rather than consider bigs jumps in last-received-from activity as a
signal to possibly reconfigure the set of wireguard peers to have
configured, instead just track the set of peers that are currently
excluded from the configuration. Easier to reason about.
Also adds a bit more logging.
This might fix an error we saw on a machine running a recent unstable
build:
2020-08-26 17:54:11.528033751 +0000 UTC: 8.6M/92.6M magicsock: [unexpected] lazy endpoint not created for [UcppE], d:42a770f678357249
2020-08-26 17:54:13.691305296 +0000 UTC: 8.7M/92.6M magicsock: DERP packet received from idle peer [UcppE]; created=false
2020-08-26 17:54:13.691383687 +0000 UTC: 8.7M/92.6M magicsock: DERP packet from unknown key: [UcppE]
If it does happen again, though, we'll have more logs.
Seems to break linux CI builder. Cannot reproduce locally,
so attempting a rollback.
This reverts commit cd7bc02ab1.
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
Without this, a freshly started ipn client will be stuck in the
"Starting" state until something triggers a call to RequestStatus.
Usually a UI does this, but until then we can sit in this state
until poked by an external event, as is evidenced by our e2e tests
locking up when DERP is attached.
(This only recently became a problem when we enabled lazy handshaking
everywhere, otherwise the wireugard tunnel creation would also
trigger a RequestStatus.)
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
For example:
$ tailscale ping -h
USAGE
ping <hostname-or-IP>
FLAGS
-c 10 max number of pings to send
-stop-once-direct true stop once a direct path is established
-verbose false verbose output
$ tailscale ping mon.ts.tailscale.com
pong from monitoring (100.88.178.64) via DERP(sfo) in 65ms
pong from monitoring (100.88.178.64) via DERP(sfo) in 252ms
pong from monitoring (100.88.178.64) via [2604:a880:2:d1::36:d001]:41641 in 33ms
Fixes#661
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
1) we weren't waking up a discoEndpoint that once existed and
went idle for 5 minutes and then got a disco message again.
2) userspaceEngine.noteReceiveActivity had a buggy check; fixed
and added a test
A comparison operator was backwards.
The bad case went:
* device A send packet to B at t=1s
* B gets added to A's wireguard config
* B gets packet
(5 minutes pass)
* some other activity happens, causing B to expire
to be removed from A's network map, since it's
been over 5 minutes since sent or received activity
* device A sends packet to B at t=5m1s
* normally, B would get added back, but the old send
time was not zero (we sent earlier!) and the time
comparison was backwards, so we never regenerated
the wireguard config.
This also refactors the code for legibility and moves constants up
top, with comments.
wireguard-go uses 3 goroutines per peer (with reasonably large stacks
& buffers).
Rather than tell wireguard-go about all our peers, only tell it about
peers we're actively communicating with. That means we need hooks into
magicsock's packet receiving path and tstun's packet sending path to
lazily create a wireguard peer on demand from the network map.
This frees up lots of memory for iOS (where we have almost nothing
left for larger domains with many users).
We should ideally do this in wireguard-go itself one day, but that'd
be a pretty big change.
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Peers advertising a discovery key know how to speak the discovery
protocol and do their own heartbeats to get through NATs and keep NATs
open. No need for the pinger except for with legacy peers.
This change adds to tsdns the ability to delegate lookups to upstream nameservers.
This is crucial for setting Magic DNS as the system resolver.
Signed-off-by: Dmytro Shynkevych <dmytro@tailscale.com>
The new deepprint package just walks a Go data structure and writes to
an io.Writer. It's not pretty like go-spew, etc.
We then use it to replace the use of UAPI (which we have a TODO to
remove) to generate signatures of data structures to detect whether
anything changed (without retaining the old copy).
This was necessary because the UAPI conversion ends up trying to do
DNS lookups which an upcoming change depends on not happening.
If there's been 5 minutes of inactivity, stop doing STUN lookups. That
means NAT mappings will expire, but they can resume later when there's
activity again.
We'll do this for all platforms later.
Updates tailscale/corp#320
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
macOS incorrectly sends packets for the local Tailscale IP
into our tunnel interface. We have to turn the packets around
and send them back to the kernel.
Fixestailscale/corp#189.
Signed-off-by: David Anderson <danderson@tailscale.com>
Otherwise iOS/macOS will reconfigure their routing every time anything
minor changes in the netmap (in particular, endpoints and DERP homes),
which is way too often.
Some users reported "network reconfigured" errors from Chrome when this
happens.
Signed-off-by: Avery Pennarun <apenwarr@tailscale.com>
We canceled the pingers in Close, but didn't wait around for their
goroutines to be cleaned up. This caused the ipn/e2e_test to catch
pingers in its resource leak check.
This commit introduces an object, but also simplifies the semantics
around the pinger's cancel functions. They no longer need to be called
while holding the mutex.
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
Instead of hard-coding the DERP map (except for cmd/tailscale netcheck
for now), get it from the control server at runtime.
And make the DERP map support multiple nodes per region with clients
picking the first one that's available. (The server will balance the
order presented to clients for load balancing)
This deletes the stunner package, merging it into the netcheck package
instead, to minimize all the config hooks that would've been
required.
Also fix some test flakes & races.
Fixes#387 (Don't hard-code the DERP map)
Updates #388 (Add DERP region support)
Fixes#399 (wgengine: flaky tests)
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
If a test calls log.Printf, 'go test' horrifyingly rearranges the
output to no longer be in chronological order, which makes debugging
virtually impossible. Let's stop that from happening by making
log.Printf panic if called from any module, no matter how deep, during
tests.
This required us to change the default error handler in at least one
http.Server, as well as plumbing a bunch of logf functions around,
especially in magicsock and wgengine, but also in logtail and backoff.
To add insult to injury, 'go test' also rearranges the output when a
parent test has multiple sub-tests (all the sub-test's t.Logf is always
printed after all the parent tests t.Logf), so we need to screw around
with a special Logf that can point at the "current" t (current_t.Logf)
in some places. Probably our entire way of using subtests is wrong,
since 'go test' would probably like to run them all in parallel if you
called t.Parallel(), but it definitely can't because the're all
manipulating the shared state created by the parent test. They should
probably all be separate toplevel tests instead, with common
setup/teardown logic. But that's a job for another time.
Signed-off-by: Avery Pennarun <apenwarr@tailscale.com>
Right now, filtering and packet injection in wgengine depend
on a patch to wireguard-go that probably isn't suitable for upstreaming.
This need not be the case: wireguard-go/tun.Device is an interface.
For example, faketun.go implements it to mock a TUN device for testing.
This patch implements the same interface to provide filtering
and packet injection at the tunnel device level,
at which point the wireguard-go patch should no longer be necessary.
This patch has the following performance impact on i7-7500U @ 2.70GHz,
tested in the following namespace configuration:
┌────────────────┐ ┌─────────────────────────────────┐ ┌────────────────┐
│ $ns1 │ │ $ns0 │ │ $ns2 │
│ client0 │ │ tailcontrol, logcatcher │ │ client1 │
│ ┌─────┐ │ │ ┌──────┐ ┌──────┐ │ │ ┌─────┐ │
│ │vethc│───────┼────┼──│vethrc│ │vethrs│──────┼─────┼──│veths│ │
│ ├─────┴─────┐ │ │ ├──────┴────┐ ├──────┴────┐ │ │ ├─────┴─────┐ │
│ │10.0.0.2/24│ │ │ │10.0.0.1/24│ │10.0.1.1/24│ │ │ │10.0.1.2/24│ │
│ └───────────┘ │ │ └───────────┘ └───────────┘ │ │ └───────────┘ │
└────────────────┘ └─────────────────────────────────┘ └────────────────┘
Before:
---------------------------------------------------
| TCP send | UDP send |
|------------------------|------------------------|
| 557.0 (±8.5) Mbits/sec | 3.03 (±0.02) Gbits/sec |
---------------------------------------------------
After:
---------------------------------------------------
| TCP send | UDP send |
|------------------------|------------------------|
| 544.8 (±1.6) Mbits/sec | 3.13 (±0.02) Gbits/sec |
---------------------------------------------------
The impact on receive performance is similar.
Signed-off-by: Dmytro Shynkevych <dmytro@tailscale.com>
This saves a layer of translation, and saves us having to
pass in extra bits and pieces of the netmap and prefs to
wgengine. Now it gets one Wireguard config, and one OS
network stack config.
Signed-off-by: David Anderson <danderson@tailscale.com>
Instead, pass in only exactly the relevant configuration pieces
that the OS network stack cares about.
Signed-off-by: David Anderson <danderson@tailscale.com>
New logic installs precise filters for subnet routes,
plays nice with other users of netfilter, and lays the
groundwork for fixing routing loops via policy routing.
Signed-off-by: David Anderson <danderson@tailscale.com>
This was only done occasionally, but was extremely disruptive
when done and is no longer necessary.
It used to be that when switching links, we had to immediately
generate handshakes to everyone we were communicating with to
punch a hole in any NAT we were talking through. (This ended up
not really working, because in the process we got rid of our
session keys and ended up having a futile conversation for many
seconds.)
Now we have DERP, our link change propogates to the other side
as a new list of endpoints, so they start spraying packets.
We will definitely get one thanks to DERP, which will cause us
to spray, opening any NAT we are behind.
The result is that for good connections, we don't trash session
keys and cause an interruption.
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
It was one of the top garbage producers on my phone.
It's slated to be deleted and replaced anyway, but this helps in the
meantime.
The go.sum changes look scary, but the new dep only adds 240 bytes to
the binary. The go.sum noise is just cmd/go being aggressive in
including a lot of stuff (which is being fixed in Go 1.15, for what I
understand). And I ran a go mod tidy, which added some too. (I had to
write a custom wrapper around go mod tidy because this mod tidy
normally breaks on tailscale.io/control being missing but referenced
in tests)
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Use this when making the ipn state transition from Starting to
Running. This way a network of quiet nodes with no active
handshaking will still transition to Active.
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
This was (presumably) missing from wgengine because the
interactions between magicsock and wireguard-go meant that the
shutdown never worked. Now those are fixed, actually shut down.
Fixes occasional flake in expanded ipn/e2e_test.
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
Because wgLock is held while some wireguard-go methods run,
trying to hold wgLock during HandshakeDone potentially creates
lock cycles between wgengine and internals of wireguard-go.
Arguably wireguard-go should call HandshakeDone in a new goroutine,
but until its API promises that, don't make any assumptions here.
Maybe for #110.
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
For 3 seconds after a successful handshake, wgengine will send a
ping packet every 300ms to its peer. This ensures the spray logic
in magicsock has something to spray.
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
This is the first, and easier, part of incremental wireguard-go
reconfiguration. It means that a new node appearing on the
network does not cause all existing nodes to re-handshake with
the other nodes they are talking to.
(This code has been running on hello.ipn.dev for a few weeks and
peers have successfully reconnected to it through many network
map updates.)
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
And make the monitor package portable with no-op implementations on
unsupported operating systems.
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
* make RouterGen return an error, not take both tunname and tundev
* also remove RouteGen taking a wireguard/device.Device; currently unused
* remove derp parameter (it'll work differently)
* unexport NewUserspaceRouter in per-OS impls, add documented wrapper
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>