Commit Graph

237 Commits

Author SHA1 Message Date
Joe Tsai
f9120eee57
wgengine: start network logger in Userspace.Reconfig (#5908)
If the wgcfg.Config is specified with network logging arguments,
then Userspace.Reconfig starts up an asynchronous network logger,
which is shutdown either upon Userspace.Close or when Userspace.Reconfig
is called again without network logging or route arguments.

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
2022-10-12 15:05:21 -07:00
Joe Tsai
24ebf161e8
net/tstun: instrument Wrapper with statistics gathering (#5847)
If Wrapper.StatisticsEnable is enabled,
then per-connection counters are maintained.
If enabled, Wrapper.StatisticsExtract must be periodically called
otherwise there is unbounded memory growth.

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
2022-10-05 12:24:30 -07:00
Andrew Dunham
e5636997c5
wgengine: don't re-allocate trimmedNodes map (#5825)
Change-Id: I512945b662ba952c47309d3bf8a1b243e05a4736
Signed-off-by: Andrew Dunham <andrew@tailscale.com>
2022-10-04 13:20:09 -04:00
Aaron Klotz
44f13d32d7 cmd/tailscaled, util/winutil: log Windows service diagnostics when the wintun device fails to install
I added new functions to winutil to obtain the state of a service and all
its depedencies, serialize them to JSON, and write them to a Logf.

When tstun.New returns a wrapped ERROR_DEVICE_NOT_AVAILABLE, we know that wintun
installation failed. We then log the service graph rooted at "NetSetupSvc".
We are interested in that specific service because network devices will not
install if that service is not running.

Updates https://github.com/tailscale/tailscale/issues/5531

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2022-09-28 16:09:10 -06:00
Brad Fitzpatrick
9bdf0cd8cd ipn/ipnlocal: add c2n /debug/{goroutines,prefs,metrics}
* and move goroutine scrubbing code to its own package for reuse
* bump capver to 45

Change-Id: I9b4dfa5af44d2ecada6cc044cd1b5674ee427575
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2022-09-26 11:16:38 -07:00
Andrew Dunham
b1867457a6
doctor: add package for running in-depth healthchecks; use in bugreport (#5413)
Change-Id: Iaa4e5b021a545447f319cfe8b3da2bd3e5e5782b
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
2022-09-26 13:07:28 -04:00
Brad Fitzpatrick
58abae1f83 net/dns/{publicdns,resolver}: add NextDNS DoH support
NextDNS is unique in that users create accounts and then get
user-specific DNS IPs & DoH URLs.

For DoH, the customer ID is in the URL path.

For IPv6, the IP address includes the customer ID in the lower bits.

For IPv4, there's a fragile "IP linking" mechanism to associate your
public IPv4 with an assigned NextDNS IPv4 and that tuple maps to your
customer ID.

We don't use the IP linking mechanism.

Instead, NextDNS is DoH-only. Which means using NextDNS necessarily
shunts all DNS traffic through 100.100.100.100 (programming the OS to
use 100.100.100.100 as the global resolver) because operating systems
can't usually do DoH themselves.

Once it's in Tailscale's DoH client, we then connect out to the known
NextDNS IPv4/IPv6 anycast addresses.

If the control plane sends the client a NextDNS IPv6 address, we then
map it to the corresponding NextDNS DoH with the same client ID, and
we dial that DoH server using the combination of v4/v6 anycast IPs.

Updates #2452

Change-Id: I3439d798d21d5fc9df5a2701839910f5bef85463
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2022-09-08 12:50:32 -07:00
Andrew Dunham
c72caa6672 wgengine/magicsock: use AF_PACKET socket + BPF to read disco messages
This is entirely optional (i.e. failing in this code is non-fatal) and
only enabled on Linux for now. Additionally, this new behaviour can be
disabled by setting the TS_DEBUG_DISABLE_AF_PACKET environment variable.

Updates #3824
Replaces #5474

Co-authored-by: Andrew Dunham <andrew@du.nham.ca>
Signed-off-by: David Anderson <danderson@tailscale.com>
2022-08-31 14:52:31 -07:00
James Tucker
ad1cc6cff9 wgengine: use Go API rather than UAPI for status
Signed-off-by: James Tucker <james@tailscale.com>
2022-08-29 15:38:16 -07:00
Brad Fitzpatrick
c66f99fcdc tailcfg, control/controlclient, ipn/ipnlocal: add c2n (control-to-node) system
This lets the control plane can make HTTP requests to nodes.

Then we can use this for future things rather than slapping more stuff
into MapResponse, etc.

Change-Id: Ic802078c50d33653ae1f79d1e5257e7ade4408fd
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2022-08-29 15:18:40 -07:00
Maisem Ali
9197dd14cc net/dns: [win] add MagicDNS entries to etc/hosts
This works around the 2.3s delay in short name lookups when SNR is
enabled.
C:\Windows\System32\drivers\etc\hosts file. We only add known hosts that
match the search domains, and we populate the list in order of
Search Domains so that our matching algorithm mimics what Windows would
otherwise do itself if SNR was off.

Updates #1659

Signed-off-by: Maisem Ali <maisem@tailscale.com>
2022-08-19 12:38:11 -05:00
Joe Tsai
03f7e4e577
util/hashx: move from sha256x (#5388) 2022-08-16 13:15:33 -07:00
Joe Tsai
1f7479466e
util/deephash: use sha256x (#5339)
Switch deephash to use sha256x.Hash.

We add sha256x.HashString to efficiently hash a string.
It uses unsafe under the hood to convert a string to a []byte.
We also modify sha256x.Hash to export the underlying hash.Hash
for testing purposes so that we can intercept all hash.Hash calls.

Performance:

	name                 old time/op    new time/op    delta
	Hash-24                19.8µs ± 1%    19.2µs ± 1%  -3.01%  (p=0.000 n=10+10)
	HashPacketFilter-24    2.61µs ± 0%    2.53µs ± 1%  -3.01%  (p=0.000 n=8+10)
	HashMapAcyclic-24      31.3µs ± 1%    29.8µs ± 0%  -4.80%  (p=0.000 n=10+9)
	TailcfgNode-24         1.83µs ± 1%    1.82µs ± 2%    ~     (p=0.305 n=10+10)
	HashArray-24            344ns ± 2%     323ns ± 1%  -6.02%  (p=0.000 n=9+10)

The performance gains is not as dramatic as sha256x over sha256 due to:
1. most of the hashing already occurring through the direct memory hashing logic, and
2. what does not go through direct memory hashing is slowed down by reflect.

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
2022-08-11 17:44:09 -07:00
Brad Fitzpatrick
ec9d13bce5 hostinfo, net/netcheck: use CutPrefix
Updates #5309

Change-Id: I37e594cfd245784bf810c493de68a66d3ff20677
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2022-08-05 15:17:44 -07:00
Andrew Dunham
f0d6f173c9
net/netcheck: try ICMP if UDP is blocked (#5056)
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
2022-08-04 17:10:13 -04:00
Tom DNetto
f50043f6cb tka,types/key: remove dependency for tailcfg & types/ packages on tka
Following the pattern elsewhere, we create a new tka-specific types package for the types
that need to couple between the serialized structure types, and tka.

Signed-off-by: Tom DNetto <tom@tailscale.com>
2022-08-04 12:51:58 -07:00
Brad Fitzpatrick
4950fe60bd syncs, all: move to using Go's new atomic types instead of ours
Fixes #5185

Change-Id: I850dd532559af78c3895e2924f8237ccc328449d
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2022-08-04 07:47:59 -07:00
Tom DNetto
4001d0bf25 assorted: plumb tka initialization & network-lock key into tailscaled
- A network-lock key is generated if it doesn't already exist, and stored in the StateStore. The public component is communicated to control during registration.
 - If TKA state exists on the filesystem, a tailnet key authority is initialized (but nothing is done with it for now).

Signed-off-by: Tom DNetto <tom@tailscale.com>
2022-08-03 14:51:47 -07:00
Brad Fitzpatrick
8725b14056 all: migrate more code code to net/netip directly
Instead of going through the tailscale.com/net/netaddr transitional
wrappers.

Updates #5162

Change-Id: I3dafd1c2effa1a6caa9b7151ecf6edd1a3fda3dd
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2022-08-02 13:59:57 -07:00
Maisem Ali
eb32847d85 tailcfg: add CapabilityFileSharingTarget to identify FileTargets
This adds the inverse to CapabilityFileSharingSend so that senders can
identify who they can Taildrop to.

Updates #2101

Signed-off-by: Maisem Ali <maisem@tailscale.com>
2022-08-02 13:52:10 -07:00
Tom DNetto
47f91dd732 cmd/tailscale{,d}: update depaware
Signed-off-by: Tom DNetto <tom@tailscale.com>
2022-07-29 12:16:32 -07:00
Brad Fitzpatrick
acc3b7f259 go.mod: bump inet.af/wf, tidy
This removes inet.af/netaddr from go.{mod,sum}.

Updates #5162

Change-Id: I7121e9fbb96d036cf188c51f0b53731570252d69
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2022-07-28 14:50:50 -07:00
Brad Fitzpatrick
a12aad6b47 all: convert more code to use net/netip directly
perl -i -npe 's,netaddr.IPPrefixFrom,netip.PrefixFrom,' $(git grep -l -F netaddr.)
    perl -i -npe 's,netaddr.IPPortFrom,netip.AddrPortFrom,' $(git grep -l -F netaddr. )
    perl -i -npe 's,netaddr.IPPrefix,netip.Prefix,g' $(git grep -l -F netaddr. )
    perl -i -npe 's,netaddr.IPPort,netip.AddrPort,g' $(git grep -l -F netaddr. )
    perl -i -npe 's,netaddr.IP\b,netip.Addr,g' $(git grep -l -F netaddr. )
    perl -i -npe 's,netaddr.IPv6Raw\b,netip.AddrFrom16,g' $(git grep -l -F netaddr. )
    goimports -w .

Then delete some stuff from the net/netaddr shim package which is no
longer neeed.

Updates #5162

Change-Id: Ia7a86893fe21c7e3ee1ec823e8aba288d4566cd8
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2022-07-25 21:53:49 -07:00
Brad Fitzpatrick
7eaf5e509f net/netaddr: start migrating to net/netip via new netaddr adapter package
Updates #5162

Change-Id: Id7bdec303b25471f69d542f8ce43805328d56c12
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2022-07-25 16:20:43 -07:00
Maisem Ali
9514ed33d2 go.mod: bump gvisor.dev/gvisor
Pick up https://github.com/google/gvisor/pull/7787

Signed-off-by: Maisem Ali <maisem@tailscale.com>
2022-07-21 16:41:18 -07:00
Brad Fitzpatrick
6b71568eb7 util/cloudenv: add Azure support & DNS IPs
And rewrite cloud detection to try to do only zero or one metadata
discovery request for all clouds, only doing a first (or second) as
confidence increases. Work remains for Windows, but a start.

And add Cloud to tailcfg.Hostinfo, which helped with testing using
"tailcfg debug hostinfo".

Updates #4983 (Linux only)
Updates #4984

Change-Id: Ib03337089122ce0cb38c34f724ba4b4812bc614e
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2022-06-30 17:03:46 -07:00
Brad Fitzpatrick
aa37aece9c ipn/ipnlocal, net/dns*, util/cloudenv: add AWS DNS support
And remove the GCP special-casing from ipn/ipnlocal; do it only in the
forwarder for *.internal.

Fixes #4980
Fixes #4981

Change-Id: I5c481e96d91f3d51d274a80fbd37c38f16dfa5cb
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2022-06-29 20:37:44 -07:00
Brad Fitzpatrick
88c2afd1e3 ipn/ipnlocal, net/dns*, util/cloudenv: specialize DNS config on Google Cloud
This does three things:

* If you're on GCP, it adds a *.internal DNS split route to the
  metadata server, so we never break GCP DNS names. This lets people
  have some Tailscale nodes on GCP and some not (e.g. laptops at home)
  without having to add a Tailnet-wide *.internal DNS route.
  If you already have such a route, though, it won't overwrite it.

* If the 100.100.100.100 DNS forwarder has nowhere to forward to,
  it forwards it to the GCP metadata IP, which forwards to 8.8.8.8.
  This means there are never errNoUpstreams ("upstream nameservers not set")
  errors on GCP due to e.g. mangled /etc/resolv.conf (GCP default VMs
  don't have systemd-resolved, so it's likely a DNS supremacy fight)

* makes the DNS fallback mechanism use the GCP metadata IP as a
  fallback before our hosted HTTP-based fallbacks

I created a default GCP VM from their web wizard. It has no
systemd-resolved.

I then made its /etc/resolv.conf be empty and deleted its GCP
hostnames in /etc/hosts.

I then logged in to a tailnet with no global DNS settings.

With this, tailscaled writes /etc/resolv.conf (direct mode, as no
systemd-resolved) and sets it to 100.100.100.100, which then has
regular DNS via the metadata IP and *.internal DNS via the metadata IP
as well. If the tailnet configures explicit DNS servers, those are used
instead, except for *.internal.

This also adds a new util/cloudenv package based on version/distro
where the cloud type is only detected once. We'll likely expand it in
the future for other clouds, doing variants of this change for other
popular cloud environments.

Fixes #4911

RELNOTES=Google Cloud DNS improvements

Change-Id: I19f3c2075983669b2b2c0f29a548da8de373c7cf
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2022-06-29 17:39:13 -07:00
Brad Fitzpatrick
13d0b8e6a4 control/controlclient, net/dnscache: use typed singleflight fork
Change-Id: I12be4c5a91ae3a812fe88d9b2d15526fdbb5a921
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2022-06-17 10:20:16 -07:00
Mihai Parparita
edc90ebc61 net/wsconn: remove homegrown wrapper for turning a websocket.Conn into a net.Conn
The one from the nhooyr/websocket package seems to work equally well.

Signed-off-by: Mihai Parparita <mihai@tailscale.com>
2022-06-07 09:28:56 -07:00
Brad Fitzpatrick
a9b4bf1535 ipn/ipnserver, cmd/tailscaled: fix peerapi on Windows
We weren't wiring up netstack.Impl to the LocalBackend in some cases
on Windows. This fixes Windows 7 when run as a service.

Updates #4750 (fixes after pull in to corp repo)

Change-Id: I9ce51b797710f2bedfa90545776b7628c7528e99
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2022-06-03 12:24:47 -07:00
Mihai Parparita
a9f32656f5 control/controlhttp: allow client and server to communicate over WebSockets
We can't do Noise-over-HTTP in Wasm/JS (because we don't have bidirectional
communication), but we should be able to do it over WebSockets. Reuses
derp WebSocket support that allows us to turn a WebSocket connection
into a net.Conn.

Updates #3157

Signed-off-by: Mihai Parparita <mihai@tailscale.com>
2022-06-02 21:20:54 -07:00
Maisem Ali
81487169f0 build_docker.sh: pin github.com/tailscale/mkctr
Signed-off-by: Maisem Ali <maisem@tailscale.com>
2022-06-01 19:55:06 +05:00
Aaron Klotz
b005b79236 net/dns, paths, util/winutil: change net/dns/windowsManager NRPT management to support more than 50 domains.
AFAICT this isn't documented on MSDN, but based on the issue referenced below,
NRPT rules are not working when a rule specifies > 50 domains.

This patch modifies our NRPT rule generator to split the list of domains
into chunks as necessary, and write a separate rule for each chunk.

For compatibility reasons, we continue to use the hard-coded rule ID, but
as additional rules are required, we generate new GUIDs. Those GUIDs are
stored under the Tailscale registry path so that we know which rules are ours.

I made some changes to winutils to add additional helper functions in support
of both the code and its test: I added additional registry accessors, and also
moved some token accessors from paths to util/winutil.

Fixes https://github.com/tailscale/coral/issues/63

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2022-05-27 14:56:09 -06:00
Aaron Klotz
c163b2a3f1 util/winutil, util/winutil/vss: remove winrestore and vss as they are unnecessary.
I wrote this code way back at the beginning of my tenure at Tailscale when we
had concerns about needing to restore deleted machine keys from backups.

We never ended up using this functionality, and the code is now getting in the
way, so we might as well remove it.

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2022-05-26 12:13:36 -06:00
Aaron Klotz
d915e0054c cmd/tailscaled: change Windows service shutdown and add optional event logging
Once a stop request is received and the service updates its status to `svc.StopPending`,
it should continue running *until the shutdown sequence is complete*, and then
return out of `(*ipnService).Execute`, which automatically sends a `svc.Stopped`
notification to Windows.

To make this happen, I changed the loop so that it runs until `doneCh` is
closed, and then returns. I also removed a spurious `svc.StopPending` notification
that the Windows Service Control Manager might be interpreting as a request for
more time to shut down.

Finally, I added some optional logging that sends a record of service notifications
to the Windows event log, allowing us to more easily correlate with any Service
Control Manager errors that are sent to the same log.

Change-Id: I5b596122e5e89c4c655fe747a612a52cb4e8f1e0
Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2022-04-29 15:13:11 -07:00
Brad Fitzpatrick
c88506caa6 ipn/ipnlocal: add Wake-on-LAN function to peerapi
No CLI support yet. Just the curl'able version if you know the peerapi
port. (like via a TSMP ping)

Updates #306

Change-Id: I0662ba6530f7ab58d0ddb24e3664167fcd1c4bcf
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2022-04-26 15:20:59 -07:00
Brad Fitzpatrick
3601b43530 ipn: add IPCVersion override func
I've done this a handful of times in the past and again today.
Time to make it a supported thing for the future.

Used while debugging tailscale/corp#4559 (macsys CLI issues)

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2022-04-25 20:51:05 -07:00
Brad Fitzpatrick
910ae68e0b util/mak: move tailssh's mapSet into a new package for reuse elsewhere
Change-Id: Idfe95db82275fd2be6ca88f245830731a0d5aecf
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2022-04-21 21:20:10 -07:00
Maisem Ali
695f8a1d7e ssh/tailssh: add support for sftp
Updates #3802

Signed-off-by: Maisem Ali <maisem@tailscale.com>
2022-04-21 10:52:22 -07:00
Brad Fitzpatrick
53588f632d Revert "wgengine/router,util/kmod: load & log xt_mark"
This reverts commit 8d6793fd70.

Reason: breaks Android build (cgo/pthreads addition)

We can try again next cycle.

Change-Id: I5e7e1730a8bf399a8acfce546a6d22e11fb835d5
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2022-04-21 09:53:23 -07:00
James Tucker
8d6793fd70 wgengine/router,util/kmod: load & log xt_mark
Attempt to load the xt_mark kernel module when it is not present. If the
load fails, log error information.

It may be tempting to promote this failure to an error once it has been
in use for some time, so as to avoid reaching an error with the iptables
invocation, however, there are conditions under which the two stages may
disagree - this change adds more useful breadcrumbs.

Example new output from tailscaled running under my WSL2:

```
router: ensure module xt_mark: "/usr/sbin/modprobe xt_mark" failed: exit status 1; modprobe: FATAL: Module xt_mark not found in directory /lib/modules/5.10.43.3-microsoft-standard-WSL2
```

Background:

There are two places to lookup modules, one is `/proc/modules` "old",
the other is `/sys/module/` "new".

There was query_modules(2) in linux <2.6, alas, it is gone.

In a docker container in the default configuration, you would get
/proc/modules and /sys/module/ both populated. lsmod may work file,
modprobe will fail with EPERM at `finit_module()` for an unpriviliged
container.

In a priviliged container the load may *succeed*, if some conditions are
met. This condition should be avoided, but the code landing in this
change does not attempt to avoid this scenario as it is both difficult
to detect, and has a very uncertain impact.

In an nspawn container `/proc/modules` is populated, but `/sys/module`
does not exist. Modern `lsmod` versions will fail to gather most module
information, without sysfs being populated with module information.

In WSL2 modules are likely missing, as the in-use kernel typically is
not provided by the distribution filesystem, and WSL does not mount in a
module filesystem of its own. Notably the WSL2 kernel supports iptables
marks without listing the xt_mark module in /sys/module, and
/proc/modules is empty.

On a recent kernel, we can ask the capabilities system about SYS_MODULE,
that will help to disambiguate between the non-privileged container case
and just being root. On older kernels these calls may fail.

Update #4329

Signed-off-by: James Tucker <james@tailscale.com>
2022-04-20 22:21:35 -07:00
Brad Fitzpatrick
8ee044ea4a ssh/tailssh: make the SSH server a singleton, register with LocalBackend
Remove the weird netstack -> tailssh dependency and instead have tailssh
register itself with ipnlocal when linked.

This makes tailssh.server a singleton, so we can have a global map of
all sessions.

Updates #3802

Change-Id: Iad5caec3a26a33011796878ab66b8e7b49339f29
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2022-04-15 13:45:39 -07:00
phirework
83c734a6e0
net/dns, util/publicdns: extract public DNS mapping into own package (#4405)
This extracts DOH mapping of known public DNS providers in
forwarder.go into its own package, to be consumed by other repos

Signed-off-by: Jenny Zhang <jz@tailscale.com>
2022-04-14 17:15:54 -04:00
James Tucker
2550acfd9d
go.mod: bump netstack for clone reset fix (#4379)
In tracking down issue #4144 and reading through the netstack code in
detail, I discovered that the packet buf Clone path did not reset the
packetbuf it was getting from the sync.Pool. The fix was sent upstream
https://github.com/google/gvisor/pull/7385, and this bump pulls that in.
At this time there is no known path that this fixes, however at the time
of upstream submission this reset at least one field that could lead to
incorrect packet routing if exercised, a situation that could therefore
lead to an information leak.

Signed-off-by: James Tucker <james@tailscale.com>
2022-04-07 19:03:18 -07:00
James Tucker
c6ac29bcc4
wgengine/netstack: disable refsvfs2 leak tracking (#4378)
In addition an envknob (TS_DEBUG_NETSTACK_LEAK_MODE) now provides access
to set leak tracking to more useful values.

Fixes #4309

Signed-off-by: James Tucker <james@tailscale.com>
2022-04-07 17:21:45 -07:00
Brad Fitzpatrick
5a44f9f5b5 tempfork: temporarily fork gliderlabs/ssh and x/crypto/ssh
While we rearrange/upstream things.

gliderlabs/ssh is forked into tempfork from our prior fork
at be8b7add40

x/crypto/ssh OTOH is forked at
https://github.com/tailscale/golang-x-crypto because it was gnarlier
to vendor with various internal packages, etc.
Its git history shows where it starts (2c7772ba30643b7a2026cbea938420dce7c6384d).

Updates #3802

Change-Id: I546e5cdf831cfc030a6c42557c0ad2c58766c65f
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2022-03-26 21:07:01 -07:00
Aaron Klotz
6e91f872af net/tshttpproxy: ensure we pass the correct flags to WinHttpOpen on Win7 and Win8.0
The best flag to use on Win7 and Win8.0 is deprecated in Win8.1, so we resolve
the flag depending on OS version info.

Fixes https://github.com/tailscale/tailscale/issues/4201

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2022-03-18 11:05:02 -06:00
Josh Bleecher Snyder
997b19545b syncs: use TryLock and TryRLock instead of unsafe
The docs say:

Note that while correct uses of TryLock do exist, they are rare,
and use of TryLock is often a sign of a deeper problem in a particular use of mutexes.

Rare code! Or bad code! Who can tell!

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
2022-03-17 10:57:41 -07:00
Josh Bleecher Snyder
8c2cb4b431 go.mod: update to latest certstore
It includes a fix to allow us to use Go 1.18.
We can now remove our Tailscale-only build tags.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
2022-03-16 16:10:29 -07:00