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>
This fixes#1833 in two ways:
* stop setting NoSNAT on non-Linux. It only matters on Linux and the flag
is hidden on non-Linux, but the code was still setting it. Because of
that, the new pref-reverting safety checks were failing when it was
changing.
* Ignore the two Linux-only prefs changing on non-Linux.
Fixes#1833
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
There's no need to warn that it was not provided on the command line
after doing a sequence of up; logout; up --args. If you're asking for
tailscale to be up, you always mean that you prefer LoggedOut to become
false.
Fixes#1828
Signed-off-by: Avery Pennarun <apenwarr@tailscale.com>
The new "tailscale up" checks previously didn't protect against
--advertise-exit-node being omitted in the case that
--advertise-routes was also provided. It wasn't done before because
there is no corresponding pref for "--advertise-exit-node"; it's a
helper flag that augments --advertise-routes. But that's an
implementation detail and we can still help users. We just have to
special case that pref and look whether the current routes include
both the v4 and v6 /0 routes.
Fixes#1767
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
This doesn't make --operator implicit (which we might do in the
future), but it at least doesn't require repeating it in the future
when it already matches $USER.
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
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>
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>
