Commit Graph

13 Commits

Author SHA1 Message Date
Josh Bleecher Snyder 9d542e08e2 wgengine/magicsock: always run ReceiveIPv6
One of the consequences of the 	bind refactoring in 6f23087175
is that attempting to bind an IPv6 socket will always
result in c.pconn6.pconn being non-nil.
If the bind fails, it'll be set to a placeholder packet conn
that blocks forever.

As a result, we can always run ReceiveIPv6 and health check it.
This removes IPv4/IPv6 asymmetry and also will allow health checks
to detect any IPv6 receive func failures.

Signed-off-by: Josh Bleecher Snyder <josharian@gmail.com>
2021-04-28 11:07:14 -07:00
Josh Bleecher Snyder fe50ded95c health: track whether we have a functional udp4 bind
Suggested-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Signed-off-by: Josh Bleecher Snyder <josharian@gmail.com>
2021-04-28 11:07:14 -07:00
Josh Bleecher Snyder 744de615f1 health, wgenegine: fix receive func health checks for the fourth time
The old implementation knew too much about how wireguard-go worked.
As a result, it missed genuine problems that occurred due to unrelated bugs.

This fourth attempt to fix the health checks takes a black box approach.
A receive func is healthy if one (or both) of these conditions holds:

* It is currently running and blocked.
* It has been executed recently.

The second condition is required because receive functions
are not continuously executing. wireguard-go calls them and then
processes their results before calling them again.

There is a theoretical false positive if wireguard-go go takes
longer than one minute to process the results of a receive func execution.
If that happens, we have other problems.

Updates #1790

Signed-off-by: Josh Bleecher Snyder <josharian@gmail.com>
2021-04-26 17:35:49 -07:00
Josh Bleecher Snyder 0d4c8cb2e1 health: delete ReceiveFunc health checks
They were not doing their job.
They need yet another conceptual re-think.
Start by clearing the decks.

Signed-off-by: Josh Bleecher Snyder <josharian@gmail.com>
2021-04-26 17:35:49 -07:00
Josh Bleecher Snyder 8d7f7fc7ce health, wgenegine: fix receive func health checks yet again
The existing implementation was completely, embarrassingly conceptually broken.

We aren't able to see whether wireguard-go's receive function goroutines
are running or not. All we can do is model that based on what we have done.
This commit fixes that model.

Fixes #1781

Signed-off-by: Josh Bleecher Snyder <josharian@gmail.com>
2021-04-23 08:42:04 -07:00
Josh Bleecher Snyder 5835a3f553 health, wgengine/magicsock: avoid receive function false positives
Avery reported a sub-ms health transition from "receiveIPv4 not running" to "ok".

To avoid these transient false-positives, be more precise about
the expected lifetime of receive funcs. The problematic case is one in which
they were started but exited prior to a call to connBind.Close.
Explicitly represent started vs running state, taking care with the order of updates.

Signed-off-by: Josh Bleecher Snyder <josharian@gmail.com>
2021-04-22 12:48:10 -07:00
Josh Bleecher Snyder f845aae761 health: track whether magicsock receive functions are running
Signed-off-by: Josh Bleecher Snyder <josharian@gmail.com>
2021-04-22 08:57:36 -07:00
David Anderson f007a9dd6b health: add DNS subsystem and plumb errors in.
Signed-off-by: David Anderson <danderson@tailscale.com>
2021-04-05 10:55:35 -07:00
Brad Fitzpatrick 85138d3183 health: track whether any network interface is up
Fixes #1562

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2021-03-22 21:42:14 -07:00
Brad Fitzpatrick 9eb65601ef health, ipn/ipnlocal: track, log overall health
Updates #1505

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2021-03-16 09:12:39 -07:00
Brad Fitzpatrick 232cfda280 wgengine/router: report to control when setPrivateNetwork fails
Fixes #1503

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2021-03-15 16:19:40 -07:00
Brad Fitzpatrick ba8c6d0775 health, controlclient, ipn, magicsock: tell health package state of things
Not yet checking anything. Just plumbing states into the health package.

Updates #1505

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2021-03-15 15:20:55 -07:00
Brad Fitzpatrick fd8e070d01 health, control/controlclient, wgengine: report when router unhealthy
Updates tailscale/corp#1338

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2021-02-18 11:48:48 -08:00