Commit Graph

15 Commits (10d130b845743c39a7c40421471fc47fb6b79153)

Author SHA1 Message Date
Andrea Gottardo d9aeb30281
net/interfaces: handle iOS network transitions (#10680)
Updates #8022
Updates #6075

On iOS, we currently rely on delegated interface information to figure out the default route interface.  The NetworkExtension framework in iOS seems to set the delegate interface only once, upon the *creation* of the VPN tunnel. If a network transition (e.g. from Wi-Fi to Cellular) happens while the tunnel is connected, it will be ignored and we will still try to set Wi-Fi as the default route because the delegated interface is not getting updated as connectivity transitions.

Here we work around this on the Swift side with a NWPathMonitor instance that observes the interface name of the first currently satisfied network path. Our Swift code will call into `UpdateLastKnownDefaultRouteInterface`, so we can rely on that when it is set.

If for any reason the Swift machinery didn't work and we don't get any updates, here we also have some fallback logic: we try finding a hardcoded Wi-Fi interface called en0. If en0 is down, we fall back to cellular (pdp_ip0) as a last resort. This doesn't handle all edge cases like USB-Ethernet adapters or multiple Ethernet interfaces, but it is good enough to ensure connectivity isn't broken.

I tested this on iPhones and iPads running iOS 17.1 and it appears to work. Switching between different cellular plans on a dual SIM configuration also works (the interface name remains pdp_ip0).

Signed-off-by: Andrea Gottardo <andrea@tailscale.com>
11 months ago
Andrew Dunham 01286af82b net/interfaces: better handle multiple interfaces in LikelyHomeRouterIP
Currently, we get the "likely home router" gateway IP and then iterate
through all IPs for all interfaces trying to match IPs to determine the
source IP. However, on many platforms we know what interface the gateway
is through, and thus we don't need to iterate through all interfaces
checking IPs. Instead, use the IP address of the associated interface.

This better handles the case where we have multiple interfaces on a
system all connected to the same gateway, and where the first interface
that we visit (as iterated by ForeachInterfaceAddress) isn't also the
default internet route.

Updates #8992

Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I8632f577f1136930f4ec60c76376527a19a47d1f
11 months 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 fa932fefe7 net/interfaces: redo how we get the default interface on macOS and iOS
With #6566 we added an external mechanism for getting the default
interface, and used it on macOS and iOS (see tailscale/corp#8201).
The goal was to be able to get the default physical interface even when
using an exit node (in which case the routing table would say that the
Tailscale utun* interface is the default).

However, the external mechanism turns out to be unreliable in some
cases, e.g. when multiple cellular interfaces are present/toggled (I
have occasionally gotten my phone into a state where it reports the pdp_ip1
interface as the default, even though it can't actually route traffic).

It was observed that `ifconfig -v` on macOS reports an "effective interface"
for the Tailscale utn* interface, which seems promising. By examining
the ifconfig source code, it turns out that this is done via a
SIOCGIFDELEGATE ioctl syscall. Though this is a private API, it appears
to have been around for a long time (e.g. it's in the 10.13 xnu release
at https://opensource.apple.com/source/xnu/xnu-4570.41.2/bsd/net/if_types.h.auto.html)
and thus is unlikely to go away.

We can thus use this ioctl if the routing table says that a utun*
interface is the default, and go back to the simpler mechanism that
we had before #6566.

Updates #7184
Updates #7188

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
Jordan Whited ea5ee6f87c
all: update golang.zx2c4.com/wireguard to github.com/tailscale/wireguard-go (#6692)
This is temporary while we work to upstream performance work in
https://github.com/WireGuard/wireguard-go/pull/64. A replace directive
is less ideal as it breaks dependent code without duplication of the
directive.

Signed-off-by: Jordan Whited <jordan@tailscale.com>
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
Brad Fitzpatrick da8def8e13 all: remove old +build tags
The //go:build syntax was introduced in Go 1.17:

https://go.dev/doc/go1.17#build-lines

gofmt has kept the +build and go:build lines in sync since
then, but enough time has passed. Time to remove them.

Done with:

    perl -i -npe 's,^// \+build.*\n,,' $(git grep -l -F '+build')

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Andrew Dunham 95f3dd1346 net/interfaces: don't dereference null pointer if no destination/netmask
Fixes #6065

Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I7159b8cbb8d5f47c0668cf83e59167f182f1defd
2 years ago
Anton Tolchanov d499afac78 net/interfaces: improve default route detection
Instead of treating any interface with a non-ifscope route as a
potential default gateway, now verify that a given route is
actually a default route (0.0.0.0/0 or ::/0).

Fixes #5879

Signed-off-by: Anton Tolchanov <anton@tailscale.com>
2 years ago
Anton Tolchanov 9c2ad7086c net/interfaces: deduplicate route table parsing on Darwin and FreeBSD
Signed-off-by: Anton Tolchanov <anton@tailscale.com>
2 years ago
Brad Fitzpatrick a12aad6b47 all: convert more code to use net/netip directly
perl -i -npe 's,netaddr.IPPrefixFrom,netip.PrefixFrom,' $(git grep -l -F netaddr.)
    perl -i -npe 's,netaddr.IPPortFrom,netip.AddrPortFrom,' $(git grep -l -F netaddr. )
    perl -i -npe 's,netaddr.IPPrefix,netip.Prefix,g' $(git grep -l -F netaddr. )
    perl -i -npe 's,netaddr.IPPort,netip.AddrPort,g' $(git grep -l -F netaddr. )
    perl -i -npe 's,netaddr.IP\b,netip.Addr,g' $(git grep -l -F netaddr. )
    perl -i -npe 's,netaddr.IPv6Raw\b,netip.AddrFrom16,g' $(git grep -l -F netaddr. )
    goimports -w .

Then delete some stuff from the net/netaddr shim package which is no
longer neeed.

Updates #5162

Change-Id: Ia7a86893fe21c7e3ee1ec823e8aba288d4566cd8
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 7eaf5e509f net/netaddr: start migrating to net/netip via new netaddr adapter package
Updates #5162

Change-Id: Id7bdec303b25471f69d542f8ce43805328d56c12
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 61cdcf4082 net/interfaces: add FreeBSD default route lookup (portmapping, etc)
Updates #4101 (probably fixes)

Change-Id: I2b75ee3ced276fb7b211f17c382621cf1ef882fa
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago