Commit Graph

157 Commits (275a20f8178cf9d028ab0c051c80ffd637c1fd02)

Author SHA1 Message Date
Brad Fitzpatrick 577f321c38 wgengine/magicsock: revise derp fallback logic
Revision to earlier 6284454ae5

Don't be sticky if we have no peers.

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
5 years ago
Brad Fitzpatrick 6284454ae5 wgengine/magicsock: if UDP blocked, pick DERP where most peers are
Updates #207

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
5 years ago
Brad Fitzpatrick d321190578 wgengine/magicsock: stringify [IPv6]:port normally in AddrSet.String 5 years ago
Brad Fitzpatrick 3c3ea8bc8a wgengine/magicsock: finish IPv6 transport support
DEBUG_INCLUDE_IPV6=1 is still required, but works now.

Updates #18 (fixes it, once env var gate is removed)
5 years ago
Brad Fitzpatrick 82ed7e527e wgengine/magicsock: remove log allocation
This was the whole point but I goofed at the last line.
5 years ago
Brad Fitzpatrick 8454bbbda5 wgengine/magicsock: more logging improvements
* remove endpoint discovery noise when results unchanged
* consistently spell derp nodes as "derp-N"
* replace "127.3.3.40:" with "derp-" in CreateEndpoint log output
* stop early DERP setup before SetPrivateKey is called;
  it just generates log nosie
* fix stringification of peer ShortStrings (it had an old %x on it,
  rendering it garbage)
* describe why derp routes are changing, with one of:
  shared home, their home, our home, alt
5 years ago
Brad Fitzpatrick 680311b3df wgengine/magicsock: fix few remaining logs without package prefix 5 years ago
Brad Fitzpatrick c473927558 wgengine/magicsock: clean up, add, improve DERP logs 5 years ago
Brad Fitzpatrick ea9310403d wgengine/magicsock: re-STUN on DERP connection death
Fixes #201
5 years ago
Brad Fitzpatrick 1ab5b31c4b derp, magicsock: send new "peer gone" frames when previous sender disconnects
Updates #150 (not yet enabled by default in magicsock)

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
5 years ago
Brad Fitzpatrick b6f77cc48d wgengine/magicsock: return early, outdent in derpWriteChanOfAddr 5 years ago
Brad Fitzpatrick dd31285ad4 wgengine/magicsock: send IPv6 using pconn6, if available
In prep for IPv6 support. Nothing should make it this far yet.
5 years ago
Brad Fitzpatrick af277a6762 controlclient, magicsock: add debug knob to request IPv6 endpoints
Add opt-in method to request IPv6 endpoints from the control plane.
For now they should just be skipped. A previous version of this CL was
unconditional and reportedly had problems that I can't reproduce. So
make it a knob until the mystery is solved.

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
5 years ago
Brad Fitzpatrick 221e7d7767 wgengine/magicsock: make log message include DERP port (node) 5 years ago
Brad Fitzpatrick 33bdcabf03 wgengine/magicsock: call stun callback w/ only valid part of STUN packet 5 years ago
David Anderson 0be475ba46 Revert "tailcfg, controlclient, magicsock: request IPv6 endpoints, but ignore them"
Breaks something deep in wireguard or magicsock's brainstem, no packets at all
can flow. All received packets fail decryption with "invalid mac1".

This reverts commit 94024355ed.

Signed-off-by: David Anderson <dave@natulte.net>
5 years ago
Brad Fitzpatrick 94024355ed tailcfg, controlclient, magicsock: request IPv6 endpoints, but ignore them
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
5 years ago
Brad Fitzpatrick 60ea635c6d wgengine/magicsock: delete inaccurate comment
I meant to include this in the earlier commit.
5 years ago
Brad Fitzpatrick a184e05290 wgengine/magicsock: listen on udp6, use it for STUN, report endpoint
More steps towards IPv6 transport.

We now send it to tailcontrol, which ignores it.

But it doesn't actually actually support IPv6 yet (outside of STUN).

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
5 years ago
Brad Fitzpatrick 7caa288213 wgengine/magicsock: rename pconn field to pconn4, in prep for pconn6 5 years ago
David Crawshaw addbdce296 wgengine, ipn: include number of active DERPs in status
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>
5 years ago
David Crawshaw 1ad78ce698 magicsock: reconnect to home DERP on key change
Typically the home DERP server is found and set on startup before
magicsock's SetPrivateKey can be called, so no DERP connection is
established. Make sure one is by kicking the home DERP tires in
SetPrivateKey.

Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
5 years ago
David Crawshaw 455ba751d9 magicsock: start connection to HOME derp immediately
The code as written intended to do this, but it repeated the
comparison of derpNum and c.myDerp after c.myDerp had been
updated, so it never executed.

Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
5 years ago
David Anderson 315a5e5355 scripts: add a license header checker.
Signed-off-by: David Anderson <dave@natulte.net>
5 years ago
Brad Fitzpatrick e085aec8ef all: update to wireguard-go API changes
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
5 years ago
Brad Fitzpatrick db2436c7ff wgengine/magicsock: don't interrupt endpoint updates, merge all mutex into one
Before, endpoint updates were constantly being interrupted and resumed
on Linux due to tons of LinkChange messages from over-zealous Linux
netlink messages (from router_linux.go)

Now that endpoint updates are fast and bounded in time anyway, just
let them run to completion, but note that another needs to be
scheduled after.

Now logs went from pages of noise to just:

root@taildoc:~# grep -i -E 'stun|endpoint update' log
2020/03/13 08:51:29 magicsock.Conn: starting endpoint update (initial)
2020/03/13 08:51:30 magicsock.Conn.ReSTUN: endpoint update active, need another later ("link-change-minor")
2020/03/13 08:51:31 magicsock.Conn: starting endpoint update (link-change-minor)
2020/03/13 08:51:31 magicsock.Conn.ReSTUN: endpoint update active, need another later ("link-change-minor")
2020/03/13 08:51:33 magicsock.Conn: starting endpoint update (link-change-minor)
2020/03/13 08:51:33 magicsock.Conn.ReSTUN: endpoint update active, need another later ("link-change-minor")
2020/03/13 08:51:35 magicsock.Conn: starting endpoint update (link-change-minor)
2020/03/13 08:51:35 magicsock.Conn.ReSTUN: endpoint update active, need another later ("link-change-minor")

Or, seen in another run:

2020/03/13 08:45:41 magicsock.Conn: starting endpoint update (periodic)
2020/03/13 08:46:09 magicsock.Conn: starting endpoint update (periodic)
2020/03/13 08:46:21 magicsock.Conn: starting endpoint update (link-change-major)
2020/03/13 08:46:37 magicsock.Conn: starting endpoint update (periodic)
2020/03/13 08:47:05 magicsock.Conn: starting endpoint update (periodic)

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
5 years ago
Brad Fitzpatrick db31550854 wgengine: don't Reconfig on boring link changes
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
5 years ago
Brad Fitzpatrick b9c6d3ceb8 netcheck: work behind UDP-blocked networks again, add tests
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
5 years ago
Brad Fitzpatrick bc73dcf204 wgengine/magicsock: don't block in Send waiting for derphttp.Send
Fixes #137
Updates #109
Updates #162
Updates #163

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
5 years ago
Brad Fitzpatrick 8807913be9 wgengine/magicsock: wait for previous DERP goroutines to end before new ones
Updates #109 (hopefully fixes, will wait for graphs to be happy)

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
5 years ago
Brad Fitzpatrick eff6dcdb4e wgengine/magicsock: log more about why we're re-STUNing 5 years ago
Brad Fitzpatrick b3ddf51a15 wgengine/magicsock: add a pointer value for logging
Updates #109

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
5 years ago
Brad Fitzpatrick b0f8931d26 wgengine/magicsock: make a test signature a bit more explicit 5 years ago
David Crawshaw 7ec54e0064 wgengine/magicsock: remove TODO
The TODO above derphttp.NewClient suggests it does network I/O,
but the derphttp client connects lazily and so creating one is
very cheap.

Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
5 years ago
Brad Fitzpatrick 01b4bec33f stunner: re-do how Stunner works
It used to make assumptions based on having Anycast IPs that are super
near. Now we're intentionally going to a bunch of different distant
IPs to measure latency.

Also, optimize how the hairpin detection works. No need to STUN on
that socket. Just use that separate socket for sending, once we know
the other UDP4 socket's endpoint. The trick is: make our test probe
also a STUN packet, so it fits through magicsock's existing STUN
routing.

This drops netcheck from ~5 seconds to ~250-500ms.

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
5 years ago
David Anderson 77af7e5436 wgengine/magicsock: mark test logfunc as a helper.
Signed-off-by: David Anderson <danderson@tailscale.com>
5 years ago
David Anderson 7eda3af034 wgengine/magicsock: clean up derp http servers on shutdown.
Failure to do this leads to fd exhaustion at -count=10000,
and increasingly poor execution north of -count=100.

Signed-off-by: David Anderson <danderson@tailscale.com>
5 years ago
David Anderson d651715528 wgengine/magicsock: synchronize test STUN shutdown.
Failure to do so triggers either a data race or a panic
in the testing package, due to racey use of t.Logf.

Signed-off-by: David Anderson <danderson@tailscale.com>
5 years ago
David Anderson 86baf60bd4 wgengine/magicsock: synchronize epUpdate cleanup on shutdown.
Signed-off-by: David Anderson <danderson@tailscale.com>
5 years ago
Brad Fitzpatrick 023df9239e Move linkstate boring change filtering to magicsock
So we can at least re-STUN on boring updates.

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
5 years ago
David Anderson 592fec7606 wgengine/magicsock: move device close to uncursed portion of test.
Device close used to suffer from deadlocks, but no longer.

Signed-off-by: David Anderson <danderson@tailscale.com>
5 years ago
Brad Fitzpatrick a265d7cbff wgengine/magicsock: in STUN-disabled test mode, let endpoint discovery proceed 5 years ago
Brad Fitzpatrick 5c1e443d34 wgengine/monitor: don't call LinkChange when interfaces look unchanged
Basically, don't trust the OS-level link monitor to only tell you
interesting things. Sanity check it.

Also, move the interfaces package into the net directory now that we
have it.
5 years ago
Brad Fitzpatrick 39c0ae1dba derp/derpmap: new DERP config package, merge netcheck into magicsock more
Fixes #153
Updates #162
Updates #163

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
5 years ago
Brad Fitzpatrick 4800926006 wgengine/magicsock: add AddrSet appendDests+UpdateDst tests 5 years ago
David Crawshaw e201f63230 magicsock: unskip tests that are reliable
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
5 years ago
David Anderson bb93d7aaba wgengine/magicsock: plumb logf throughout, and expose in Options.
Signed-off-by: David Anderson <danderson@tailscale.com>
5 years ago
Brad Fitzpatrick f42b9b6c9a wgengine/magicsock: don't discard UDP packet on UDP+DERP race
Fixes #155

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
5 years ago
David Anderson e3172ae267 wgengine/magicsock: uncurse TestDeviceStartStop, let CI run it.
Signed-off-by: David Anderson <danderson@tailscale.com>
5 years ago
David Anderson f265603110 wgengine/magicsock: fix data race in ReceiveIPv4.
The UDP reader goroutine was clobbering `n` and `err` from the
main goroutine, whose accesses are not synchronized the way `b` is.

Signed-off-by: David Anderson <danderson@tailscale.com>
5 years ago
David Anderson 77354d4617 wgengine/magicsock: unblock wireguard-go's read on magicsock shutdown.
wireguard-go closes magicsock, and expects this to unblock reads
so that its internal goroutines can wind down. We were incorrectly
blocking the read indefinitey and breaking this contract.

Signed-off-by: David Anderson <danderson@tailscale.com>
5 years ago
David Anderson fdee5fb639 wgengine/magicsock: don't mutexly reach inside Conn to tweak DERP settings.
Signed-off-by: David Anderson <danderson@tailscale.com>
5 years ago
David Anderson 643bf14653 wgengine/magicsock: disable the new ping test.
It's extremely flaky in several dimensions, as well as very slow.
It's making the CI completely red all the time without telling us
useful information.

Set RUN_CURSED_TESTS=1 to run locally.
5 years ago
David Anderson c8ebac2def wgengine/magicsock: try deflaking again.
This change just alters the semantics of the one flaky test, without
trying to speed up timeouts on the others. Empirically, speeding up
the timeouts causes _more_ flakes right now :(
5 years ago
David Anderson cd1ac63b4c Revert "wgengine/magicsock: temporarily deflake."
This reverts commit c5835c6ced.
5 years ago
David Anderson c5835c6ced wgengine/magicsock: temporarily deflake.
The remaining flake occurs due to a mysterious packet loss. This
doesn't affect normal tailscaled operations, so until I track down
where the loss occurs and fix it, the flaky test is going to be
lenient about packet loss (but not about whether the spray logic
worked).

Signed-off-by: David Anderson <danderson@tailscale.com>
5 years ago
Brad Fitzpatrick 61d83f759b wgengine/magicsock: remove redundant derpMagicIP comparison
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
5 years ago
David Anderson bd60a750e8 wgengine/magicsock: fix packet spraying test to (mostly) pass.
It previously passed incorrectly due to bugs. With those fixed,
it becomes flaky for 2 reasons. One of them is the wireguard handshake
race, which can eat the 1st sprayed packet and prevent roamAddr
discovery. This change fixes that failure, by spreading the test
traffic out enough that additional spraying occurs.

Signed-Off-By: David Anderson <danderson@tailscale.com>
5 years ago
David Anderson ef31dd7bb5 wgengine/magicsock: check all 3 fast paths independently.
The previous code would skip the DERP short-circuit if roamAddr
was set, which is not what we wanted. More generally, hitting
any of the fast path conditions is a direct return, so we can
just have 3 standalone branches rather than 'else if' stuff.

Signed-Off-By: David Anderson <danderson@tailscale.com>
5 years ago
David Anderson 05a52746a4 wgengine/magicsock: fix destination selection logic to work with DERP.
The effect is subtle: when we're not spraying packets, and have not yet
figured out a curAddr, and we're not spraying, we end up sending to
whatever the first IP is in the iteration order. In English, that
means "when we have no idea where to send packets, and we've given
up on sending to everyone, just send to the first addr we see in
the list."

This is, in general, what we want, because the addrs are in sorted
preference order, low to high, and DERP is the least preferred
destination. So, when we have no idea where to send, send to DERP,
right?

... Except for very historical reasons, appendDests iterated through
addresses in _reverse_ order, most preferred to least preferred.
crawshaw@ believes this was part of the earliest handshaking
algorithm magicsock had, where it slowly iterated through possible
destinations and poked handshakes to them one at a time.

Anyway, because of this historical reverse iteration, in the case
described above of "we have no idea where to send", the code would
end up sending to the _most_ preferred candidate address, rather
than the _least_ preferred. So when in doubt, we'd end up firing
packets into the blackhole of some LAN address that doesn't work,
and connectivity would not work.

This case only comes up if all your non-DERP connectivity options
have failed, so we more or less failed to detect it because we
didn't have a pathological test box deployed. Worse, codependent
bug 2839854994 made DERP accidentally
work sometimes anyway by incorrectly exploiting roamAddr behavior,
albeit at the cost of making DERP traffic symmetric. In fixing
DERP to once again be asymmetric, we effectively removed the
bandaid that was concealing this bug.

Signed-Off-By: David Anderson <danderson@tailscale.com>
5 years ago
David Anderson 97e58ad44d wgengine/magicsock: only set addrByKey once in CreateEndpoint.
Signed-Off-By: David Anderson <danderson@tailscale.com>
5 years ago
Brad Fitzpatrick fbab12c94c wgengine/magicsock: skip netcheck if external STUN aren't in use
Updates #146 (not a complete fix yet probably)
5 years ago
Brad Fitzpatrick fe0051fafd wgengine/magicsock: expand AddrSet.addrs comment 5 years ago
David Anderson 2839854994 wgengine/magicsock: never set a DERP server as a roamAddr.
DERP traffic is asymmetric by design, with nodes always sending
to their peer's home DERP server. However, if roamAddr is set,
magicsock will always push data there, rather than let DERP
server selection do its thing, so we end up accidentally
creating a symmetric flow.

Signed-Off-By: David Anderson <danderson@tailscale.com>
5 years ago
David Anderson 4f5c0da1ae wgengine/magicsock: log when home DERP server changes. 5 years ago
Brad Fitzpatrick 6978b93bdd derp, magicsock: track home (preferred) vs visiting connections for stats 5 years ago
Brad Fitzpatrick 12b77f30ad wgengine/magicsock: close stale DERP connections 5 years ago
Brad Fitzpatrick 2cff9016e4 net/dnscache: add overly simplistic DNS cache package for selective use
I started to write a full DNS caching resolver and I realized it was
overkill and wouldn't work on Windows even in Go 1.14 yet, so I'm
doing this tiny one instead for now, just for all our netcheck STUN
derp lookups, and connections to DERP servers. (This will be caching a
exactly 8 DNS entries, all ours.)

Fixes #145 (can be better later, of course)
5 years ago
Brad Fitzpatrick a36ccb8525 wgengine/magicsock: actually add to the activeDerp map
Fixes bug just introduced in 8f9849c140; not tested enough :(
5 years ago
Brad Fitzpatrick 8f9849c140 wgengine/magicsock: collapse three DERP maps down into one 5 years ago
Brad Fitzpatrick 40ebba1373 magicsock: use [unexpected] convention more
Fixes #136 (not entirely, but we have a convention now)
5 years ago
Brad Fitzpatrick 848a2bddf0 wgengine/magicsock: update set of DERP nodes 5 years ago
David Crawshaw 7932481b95 magicsock: lookup AddrSet by key from DERP
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
5 years ago
Brad Fitzpatrick eac62ec5ff ipn, wgengine/magicsock: add ipn.Prefs.DisableDERP bool
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
5 years ago
Brad Fitzpatrick bf704a5218 derp: protocol negotiation, add v2: send src pub keys to clients in packets
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
5 years ago
David Crawshaw a65b2a0efd magicsock: add some DERP tests
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
5 years ago
David Crawshaw a33419167b magicsock: plumb through derpTLSConfig variable (for testing)
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
5 years ago
David Crawshaw caec2c7e8b magicsock: test sequence of pings
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
5 years ago
David Crawshaw 9f584414d9 magicsock: simple ping test via magicsock
Passes `go test -count=20 -race ./wgengine/magicsock`

Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
5 years ago
David Crawshaw 34859f8e7d wgengine, magicsock: add a CreateBind method
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
5 years ago
David Crawshaw 75e62d318f magicsock: use local STUN server in tests
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
5 years ago
Brad Fitzpatrick b27d4c017a magicsock, wgengine, ipn, controlclient: plumb regular netchecks to map poll
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
5 years ago
Brad Fitzpatrick 724c37fb41 wgengine/magicsock: start tracking nearest DERP node 5 years ago
Brad Fitzpatrick 4675c70464 wgengine/magicsock: check STUN regularly 5 years ago
Brad Fitzpatrick bc7bc43fb8 magicsock, interfaces: move some code from magicsock to interfaces 5 years ago
Brad Fitzpatrick af7a01d6f0 wgengine/magicsock: drop donec channel, rename epUpdateCtx to serve its purpose 5 years ago
David Crawshaw cc4afa775f magicsock: rate limit send error log messages
The x/time/rate dependency adds 24kb to tailscaled binary size.

Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
5 years ago
David Crawshaw 0752c77dc2 magicsock: keep DERP magic IPs out of the address map
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
5 years ago
David Crawshaw c6550135d5 magicsock: remove the index from indexedAddrs
The value predates the introduction of AddrSet which replaces
the index by tracking curAddr directly.

Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
5 years ago
Brad Fitzpatrick 1abf2da392 wgengine/magicsock: reset favorite address on handshakes
Updates #92 (not a complete fix; could be better/faster?)

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
5 years ago
Brad Fitzpatrick 67ede8d6d2 wgengine, magicsock: fix SetPrivateKey data race
Updates #112

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
5 years ago
Brad Fitzpatrick c185e6b4b0 stunner: support IPv6, add latency info to callbacks, use unique TxIDs per retry
And some more docs.

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
5 years ago
David Crawshaw a6ad3c46e2 magicsock: spray some normal packets after a handshake
In particular, this is designed to catch the case where a
HandshakeInitiation packet is sent out but the intermediate NATs
have not been primed, so the packet passes over DERP.
In that case, the HandshakeResponse also comes back over DERP,
and the connection proceeds via DERP without ever trying to punch
through the NAT.

With this change, the HandshakeResponse (which was sprayed out
and so primed one NAT) triggers an UpdateDst, which triggers
the extra spray logic.

(For this to work, there has to be an initial supply of packets
to send on to a peer for the three seconds following a handshake.
The source of these packets is left as a future exercise.)

Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
5 years ago
Brad Fitzpatrick 8696b17b5f wgengine/magicsock: turn off DERP log spamminess by default
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
5 years ago
Brad Fitzpatrick 7a3b91390b wgengine/magicsock: fix crash in Send when Endpoint isn't an AddrSet
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
5 years ago
David Crawshaw 868cfae84f wgengine, magicsock: adjust for wireguard-go conn/device package split
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
5 years ago
Brad Fitzpatrick cc7b9b0dff control/controlclient: fix priority of DERP server, add comment 5 years ago
Brad Fitzpatrick c02f4b5a1f control/controlclient: add temporary mechanism to force derp on
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
5 years ago
Brad Fitzpatrick 525bf1f3d2 wgengine/magicsock: remember fixed port number preference
So LinkChange events rebind to the same port when possible.
5 years ago
Brad Fitzpatrick 379a3125fd derp, wgengine/magicsock: support more than just packets from Client.Recv
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
5 years ago