DNS names consist of labels, but outside of length limits, DNS
itself permits any content within the labels. Some records require
labels to conform to hostname limitations (which is what we implemented
before), but not all.
Fixes#2024.
Signed-off-by: David Anderson <danderson@tailscale.com>
(cherry picked from commit caaefa00a0)
We were crashing on in initPeerAPIListener when called from
authReconfig when b.netMap is nil. But authReconfig already returns
before the call to initPeerAPIListener when b.netMap is nil, but it
releases the b.mu mutex before calling initPeerAPIListener which
reacquires it and assumes it's still nil.
The only thing that can be setting it to nil is setNetMapLocked, which
is called by ResetForClientDisconnect, Logout/logout, or Start, all of
which can happen during an authReconfig.
So be more defensive.
Fixes#1996
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
(cherry picked from commit ecfb2639cc)
On clean installs we didn't set use iptables, but during upgrades it
looks like we could use old prefs that directed us to go into the iptables
paths that might fail on Synology.
Updates #1995Fixestailscale/tailscale-synology#57 (I think)
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
(cherry picked from commit a04801e037)
We don't use iptables on Synology, so don't scare the user.
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
(cherry picked from commit cdd231cb7d)
The resulting empty Prefs had AllowSingleHosts=false and
Routeall=false, so that on iOS if you did these steps:
- Login and leave running
- Terminate the frontend
- Restart the frontend (fast path restart, missing prefs)
- Set WantRunning=false
- Set WantRunning=true
...then you would have Tailscale running, but with no routes. You would
also accidentally disable the ExitNodeID/IP prefs (symptom: the current
exit node setting didn't appear in the UI), but since nothing
else worked either, you probably didn't notice.
The fix was easy enough. It turns out we already knew about the
problem, so this also fixes one of the BUG entries in state_test.
Fixes: #1918 (BUG-1) and some as-yet-unreported bugs with exit nodes.
Signed-off-by: Avery Pennarun <apenwarr@tailscale.com>
Previously, there was no server round trip required to log out, so when
you asked ipnlocal to Logout(), it could clear the netmap immediately
and switch to NeedsLogin state.
In v1.8, we added a true Logout operation. ipn.Logout() would trigger
an async cc.StartLogout() and *also* immediately switch to NeedsLogin.
Unfortunately, some frontends would see NeedsLogin and immediately
trigger a new StartInteractiveLogin() operation, before the
controlclient auth state machine actually acted on the Logout command,
thus accidentally invalidating the entire logout operation, retaining
the netmap, and violating the user's expectations.
Instead, add a new LogoutFinished signal from controlclient
(paralleling LoginFinished) and, upon starting a logout, don't update
the ipn state machine until it's received.
Updates: #1918 (BUG-2)
Signed-off-by: Avery Pennarun <apenwarr@tailscale.com>
This code path is very tricky since it was originally designed for the
"re-authenticate to refresh my keys" use case, which didn't want to
lose the original session even if the refresh cycle failed. This is why
it acts differently from the Logout(); Login(); case.
Maybe that's too fancy, considering that it probably never quite worked
at all, for switching between users without logging out first. But it
works now.
This was more invasive than I hoped, but the necessary fixes actually
removed several other suspicious BUG: lines from state_test.go, so I'm
pretty confident this is a significant net improvement.
Fixestailscale/corp#1756.
Signed-off-by: Avery Pennarun <apenwarr@tailscale.com>
If the engine was shutting down from a previous session
(e.closing=true), it would return an error code when trying to get
status. In that case, ipnlocal would never unblock any callers that
were waiting on the status.
Not sure if this ever happened in real life, but I accidentally
triggered it while writing a test.
Signed-off-by: Avery Pennarun <apenwarr@tailscale.com>
A couple of code paths in ipnserver use a NewBackendServer with a nil
backend just to call the callback with an encapsulated error message.
This covers a panic case seen in logs.
For #1920
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
interfaces.Tailscale only returns an interface if it has at least one Tailscale
IP assigned to it. In the resolved DNS manager, when we're called upon to tear
down DNS config, the interface no longer has IPs.
Instead, look up the interface index on construction and reuse it throughout
the daemon lifecycle.
Fixes#1892.
Signed-off-by: David Anderson <dave@natulte.net>
(cherry picked from commit cfde997699)
This reverts commit 7d16c8228b.
I have no idea how I ended up here. The bug I was fixing with this change
fails to reproduce on Ubuntu 18.04 now, and this change definitely does
break 20.04, 20.10, and Debian Buster. So, until we can reliably reproduce
the problem this was meant to fix, reverting.
Part of #1875
Signed-off-by: David Anderson <dave@natulte.net>
(cherry picked from commit 3c8e230ee1)
The old way was way too fragile and had felt like it had more special
cases than normal cases. (see #1874, #1860, #1834, etc) It became very
obvious the old algorithm didn't work when we made the output be
pretty and try to show the user the command they need to run in
5ecc7c7200 for #1746)
The new algorithm is to map the prefs (current and new) back to flags
and then compare flags. This nicely handles the OS-specific flags and
the n:1 and 1:n flag:pref cases.
No change in the existing already-massive test suite, except some ordering
differences (the missing items are now sorted), but some new tests are
added for behavior that was broken before. In particular, it now:
* preserves non-pref boolean flags set to false, and preserves exit
node IPs (mapping them back from the ExitNodeID pref, as well as
ExitNodeIP),
* doesn't ignore --advertise-exit-node when doing an EditPrefs call
(#1880)
* doesn't lose the --operator on the non-EditPrefs paths (e.g. with
--force-reauth, or when the backend was not in state Running).
Fixes#1880
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
(cherry picked from commit 5190435d6e)
Needed for the "up checker" to map back from exit node stable IDs (the
ipn.Prefs.ExitNodeID) back to an IP address in error messages.
But also previously requested so people can use it to then make API
calls. The upcoming "tailscale admin" subcommand will probably need it
too.
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
(cherry picked from commit e72ed3fcc2)
The --advertise-routes and --advertise-exit-node flags both mutating
one pref is the gift that keeps on giving.
I need to rewrite the this up warning code to first map prefs back to
flag values and then just compare flags instead of comparing prefs,
but this is the minimal fix for now.
This also includes work on the tests, to make them easier to write
(and more accurate), by letting you write the flag args directly and
have that parse into the upArgs/MaskedPrefs directly, the same as the
code, rather than them being possibly out of sync being written by
hand.
Fixes https://twitter.com/EXPbits/status/1390418145047887877
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
(cherry picked from commit e78e26b6fb)
The earlier eb06ec172f fixed
the flaky SSH issue (tailscale/corp#1725) by making sure that packets
addressed to Tailscale IPs in hybrid netstack mode weren't delivered
to netstack, but another issue remained:
All traffic handled by netstack was also potentially being handled by
the host networking stack, as the filter hook returned "Accept", which
made it keep processing. This could lead to various random racey chaos
as a function of OS/firewalls/routes/etc.
Instead, once we inject into netstack, stop our caller's packet
processing.
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Whenever we dropped a packet due to ACLs, wireguard-go was logging:
Failed to write packet to TUN device: packet dropped by filter
Instead, just lie to wireguard-go and pretend everything is okay.
Fixes#1229
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Upstream wireguard-go renamed the interface method
from CreateEndpoint to ParseEndpoint.
I updated the log call site but not the allowlist.
Signed-off-by: Josh Bleecher Snyder <josharian@gmail.com>
#1817 removed the only place in our CI where we executed our benchmark code.
Fix that by executing it everywhere.
The benchmarks are generally cheap and fast,
so this should add minimal overhead.
Signed-off-by: Josh Bleecher Snyder <josharian@gmail.com>
To prevent issues like #1786, run staticcheck on the primary GOOSes:
linux, mac, and windows.
Windows also has a fair amount of GOARCH-specific code.
If we ever have GOARCH staticcheck failures on other GOOSes,
we can expand the test matrix further.
This requires installing the staticcheck binary so that
we can execute it with different GOOSes.
Signed-off-by: Josh Bleecher Snyder <josharian@gmail.com>
This is needed because the original opts.Prefs field was at some point
subverted for use in frontend->backend state migration for backward
compatibility on some platforms. We still need that feature, but we
also need the feature of providing the full set of prefs from
`tailscale up`, *not* including overwriting the prefs.Persist keys, so
we can't use the original field from `tailscale up`.
`tailscale up` had attempted to compensate for that by doing SetPrefs()
before Start(), but that violates the ipn.Backend contract, which says
you should call Start() before anything else (that's why it's called
Start()). As a result, doing SetPrefs({ControlURL=...,
WantRunning=true}) would cause a connection to the *previous* control
server (because WantRunning=true), and then connect to the *new*
control server only after running Start().
This problem may have been avoided before, but only by pure luck.
It turned out to be relatively harmless since the connection to the old
control server was immediately closed and replaced anyway, but it
created a race condition that could have caused spurious notifications
or rejected keys if the server responded quickly.
As already covered by existing TODOs, a better fix would be to have
Start() get out of the business of state migration altogether. But
we're approaching a release so I want to make the minimum possible fix.
Fixes#1840.
Signed-off-by: Avery Pennarun <apenwarr@tailscale.com>
We were over-eager in running tailscale in GUI mode.
f42ded7acf fixed that by
checking for a variety of shell-ish env vars and using those
to force us into CLI mode.
However, for reasons I don't understand, those shell env vars
are present when Xcode runs Tailscale.app on my machine.
(I've changed no configs, modified nothing on a brand new machine.)
Work around that by adding an additional "only in GUI mode" check.
Signed-off-by: Josh Bleecher Snyder <josharian@gmail.com>
