Commit Graph

8 Commits (ab7749aed7ba40f52108c1cb6d2ae64cb8314dff)

Author SHA1 Message Date
James Tucker 9ed3a061c3 net/netns: fix segv when no tailscale interface is found
`interfaces.Tailscale()` returns all zero values when it finds no
Tailscale interface and encounters no errors. The netns package was
treating no error as a signal that it would receive a non-zero pointer
value leading to nil pointer dereference.

Observed in:

```
--- FAIL: TestGetInterfaceIndex (0.00s)
    --- FAIL: TestGetInterfaceIndex/IP_and_port (0.00s)
panic: runtime error: invalid memory address or nil pointer dereference [recovered]
        panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x2 addr=0x0 pc=0x1029eb7d8]

goroutine 7 [running]:
testing.tRunner.func1.2({0x102a691e0, 0x102bc05c0})
        /Users/raggi/.cache/tailscale-go/src/testing/testing.go:1526 +0x1c8
testing.tRunner.func1()
        /Users/raggi/.cache/tailscale-go/src/testing/testing.go:1529 +0x384
panic({0x102a691e0, 0x102bc05c0})
        /Users/raggi/.cache/tailscale-go/src/runtime/panic.go:884 +0x204
tailscale.com/net/netns.getInterfaceIndex(0x14000073f28, 0x1028d0284?, {0x1029ef3b7, 0xa})
        /Users/raggi/src/github.com/tailscale/tailscale/net/netns/netns_darwin.go:114 +0x228
tailscale.com/net/netns.TestGetInterfaceIndex.func2(0x14000138000)
        /Users/raggi/src/github.com/tailscale/tailscale/net/netns/netns_darwin_test.go:37 +0x54
testing.tRunner(0x14000138000, 0x140000551b0)
        /Users/raggi/.cache/tailscale-go/src/testing/testing.go:1576 +0x10c
created by testing.(*T).Run
        /Users/raggi/.cache/tailscale-go/src/testing/testing.go:1629 +0x368
FAIL    tailscale.com/net/netns 0.824s
```

Fixes #8064

Signed-off-by: James Tucker <jftucker@gmail.com>
2 years ago
Mihai Parparita 7330aa593e all: avoid repeated default interface lookups
On some platforms (notably macOS and iOS) we look up the default
interface to bind outgoing connections to. This is both duplicated
work and results in logspam when the default interface is not available
(i.e. when a phone has no connectivity, we log an error and thus cause
more things that we will try to upload and fail).

Fixed by passing around a netmon.Monitor to more places, so that we can
use its cached interface state.

Fixes #7850
Updates #7621

Signed-off-by: Mihai Parparita <mihai@tailscale.com>
2 years ago
Mihai Parparita c7cea825ae net/netns: don't log errors when we can't get the default route on Darwin
It's somewhat common (e.g. when a phone has no reception), and leads to
lots of logspam.

Updates #7850

Signed-off-by: Mihai Parparita <mihai@tailscale.com>
2 years ago
Mihai Parparita 62f4df3257 net/interfaces, net/netns: add node attributes to control default interface getting and binding
With #6566 we started to more aggressively bind to the default interface
on Darwin. We are seeing some reports of the wrong cellular interface
being chosen on iOS. To help with the investigation, this adds to knobs
to control the behavior changes:
- CapabilityDebugDisableAlternateDefaultRouteInterface disables the
  alternate function that we use to get the default interface on macOS
  and iOS (implemented in tailscale/corp#8201). We still log what it
  would have returned so we can see if it gets things wrong.
- CapabilityDebugDisableBindConnToInterface is a bigger hammer that
  disables binding of connections to the default interface altogether.

Updates #7184
Updates #7188

Signed-off-by: Mihai Parparita <mihai@tailscale.com>
2 years ago
Will Norris 71029cea2d all: update copyright and license headers
This updates all source files to use a new standard header for copyright
and license declaration.  Notably, copyright no longer includes a date,
and we now use the standard SPDX-License-Identifier header.

This commit was done almost entirely mechanically with perl, and then
some minimal manual fixes.

Updates #6865

Signed-off-by: Will Norris <will@tailscale.com>
2 years ago
Andrew Dunham 50da265608 net/netns: add post-review comments
Follow-up to #7065 with some comments from Brad's review.

Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: Ia1219f4fa25479b2dada38ffe421065b408c5954
2 years ago
Andrew Dunham 2703d6916f net/netns: add functionality to bind outgoing sockets based on route table
When turned on via environment variable (off by default), this will use
the BSD routing APIs to query what interface index a socket should be
bound to, rather than binding to the default interface in all cases.

Updates #5719
Updates #5940

Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: Ib4c919471f377b7a08cd3413f8e8caacb29fee0b
2 years ago
Mihai Parparita 79f3a5d753 net/netns, net/interfaces: explicitly bind sockets to the default interface on all Darwin variants
We were previously only doing this for tailscaled-on-Darwin, but it also
appears to help on iOS. Otherwise, when we rebind magicsock UDP
connections after a cellular -> WiFi interface change they still keep
using cellular one.

To do this correctly when using exit nodes, we need to exclude the
Tailscale interface when getting the default route, otherwise packets
cannot leave the tunnel. There are native macOS/iOS APIs that we can
use to do this, so we allow those clients to override the implementation
of DefaultRouteInterfaceIndex.

Updates #6565, may also help with #5156

Signed-off-by: Mihai Parparita <mihai@tailscale.com>
2 years ago