The ipn.NewPrefs func returns a populated ipn.Prefs for historical
reasons. It's not used or as important as it once was, but it hasn't
yet been removed. Meanwhile, it contains some default values that are
used on some platforms. Notably, for this bug (#1725), Windows/Mac use
its Prefs.RouteAll true value (to accept subnets), but Linux users
have always gotten a "false" value for that, because that's what
cmd/tailscale's CLI default flag is _for all operating systems_. That
meant that "tailscale up" was rightfully reporting that the user was
changing an implicit setting: RouteAll was changing from true with
false with the user explicitly saying so.
An obvious fix might be to change ipn.NewPrefs to return
Prefs.RouteAll == false on some platforms, but the logic is
complicated by darwin: we want RouteAll true on windows, android, ios,
and the GUI mac app, but not the CLI tailscaled-on-macOS mode. But
even if we used build tags (e.g. the "redo" build tag) to determine
what the default is, that then means we have duplicated and differing
"defaults" between both the CLI up flags and ipn.NewPrefs. Furthering
that complication didn't seem like a good idea.
So, changing the NewPrefs defaults is too invasive at this stage of
the release, as is removing the NewPrefs func entirely.
Instead, tweak slightly the semantics of the ipn.Prefs.ControlURL
field. This now defines that a ControlURL of the empty string means
both "we're uninitialized" and also "just use the default".
Then, once we have the "empty-string-means-unintialized" semantics,
use that to suppress "tailscale up"'s recent implicit-setting-revert
checking safety net, if we've never initialized Tailscale yet.
And update/add tests.
Fixes#1725
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Will add more tests later but this locks in all the existing warnings
and errors at least, and some of the existing non-error behavior.
Mostly I want this to exist before I actually fix#1725.
Updates #1725
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
And fix PeerSeenChange bug where it was ignored unless there were
other peer changes.
Updates tailscale/corp#1574
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.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>
They were scattered/duplicated in misc places before.
It can't be in the client package itself for circular dep reasons.
This new package is basically tailcfg but for localhost
communications, instead of to control.
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
This changes the behavior of "tailscale up".
Previously "tailscale up" always did a new Start and reset all the settings.
Now "tailscale up" with no flags just brings the world [back] up.
(The opposite of "tailscale down").
But with flags, "tailscale up" now only is allowed to change
preferences if they're explicitly named in the flags. Otherwise it's
an error. Or you need to use --reset to explicitly nuke everything.
RELNOTE=tailscale up change
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Some paths already didn't. And in the future I hope to shut all the
notify funcs down end-to-end when nothing is connected (as in the
common case in tailscaled). Then we can save some JSON encoding work.
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
We've been slowly making Start less special and making IPN a
multi-connection "watch" bus of changes, but this Start specialness
had remained.
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
