The iptables package we use doesn't include command output, so we're
left with guessing what went wrong most of the time. This will at
least narrow things down to which operation failed.
Signed-off-by: David Anderson <danderson@tailscale.com>
Instead, pass in only exactly the relevant configuration pieces
that the OS network stack cares about.
Signed-off-by: David Anderson <danderson@tailscale.com>
New logic installs precise filters for subnet routes,
plays nice with other users of netfilter, and lays the
groundwork for fixing routing loops via policy routing.
Signed-off-by: David Anderson <danderson@tailscale.com>
This depends on improved support from the control server, to send the
new subnet width (Bits) fields. If these are missing, we fall back to
assuming their value is /32.
Conversely, if the server sends Bits fields to an older client, it will
interpret them as /32 addresses. Since the only rules we allow are
"accept" rules, this will be narrower or equal to the intended rule, so
older clients will simply reject hosts on the wider subnet (fail
closed).
With this change, the internal filter.Matches format has diverged
from the wire format used by controlclient, so move the wire format
into tailcfg and convert it to filter.Matches in controlclient.
Signed-off-by: Avery Pennarun <apenwarr@tailscale.com>
Longer term, we should probably update the packet filter to be fully
stateful, for both TCP and ICMP. That is, only ICMP packets related to
a session *we* initiated should be allowed back in. But this is
reasonably secure for now, since wireguard is already trimming most
traffic. The current code would not protect against eg. Ping-of-Death style
attacks from VPN nodes.
Fixestailscale/tailscale#290.
Signed-off-by: Avery Pennarun <apenwarr@tailscale.com>
This was only done occasionally, but was extremely disruptive
when done and is no longer necessary.
It used to be that when switching links, we had to immediately
generate handshakes to everyone we were communicating with to
punch a hole in any NAT we were talking through. (This ended up
not really working, because in the process we got rid of our
session keys and ended up having a futile conversation for many
seconds.)
Now we have DERP, our link change propogates to the other side
as a new list of endpoints, so they start spraying packets.
We will definitely get one thanks to DERP, which will cause us
to spray, opening any NAT we are behind.
The result is that for good connections, we don't trash session
keys and cause an interruption.
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
It was one of the top garbage producers on my phone.
It's slated to be deleted and replaced anyway, but this helps in the
meantime.
The go.sum changes look scary, but the new dep only adds 240 bytes to
the binary. The go.sum noise is just cmd/go being aggressive in
including a lot of stuff (which is being fixed in Go 1.15, for what I
understand). And I ran a go mod tidy, which added some too. (I had to
write a custom wrapper around go mod tidy because this mod tidy
normally breaks on tailscale.io/control being missing but referenced
in tests)
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
The docs on magicsock.Conn stated that they implemented the
wireguard/device.Bind interface, yet this type does not exist. In
reality, the Conn type implements the wireguard/conn.Bind interface.
I also fixed a small typo in the same file.
Signed-off-by: Blake Gentry <blakesgentry@gmail.com>
* remove endpoint discovery noise when results unchanged
* consistently spell derp nodes as "derp-N"
* replace "127.3.3.40:" with "derp-" in CreateEndpoint log output
* stop early DERP setup before SetPrivateKey is called;
it just generates log nosie
* fix stringification of peer ShortStrings (it had an old %x on it,
rendering it garbage)
* describe why derp routes are changing, with one of:
shared home, their home, our home, alt
Add opt-in method to request IPv6 endpoints from the control plane.
For now they should just be skipped. A previous version of this CL was
unconditional and reportedly had problems that I can't reproduce. So
make it a knob until the mystery is solved.
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Breaks something deep in wireguard or magicsock's brainstem, no packets at all
can flow. All received packets fail decryption with "invalid mac1".
This reverts commit 94024355ed.
Signed-off-by: David Anderson <dave@natulte.net>
More steps towards IPv6 transport.
We now send it to tailcontrol, which ignores it.
But it doesn't actually actually support IPv6 yet (outside of STUN).
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Use this when making the ipn state transition from Starting to
Running. This way a network of quiet nodes with no active
handshaking will still transition to Active.
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
Typically the home DERP server is found and set on startup before
magicsock's SetPrivateKey can be called, so no DERP connection is
established. Make sure one is by kicking the home DERP tires in
SetPrivateKey.
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
The code as written intended to do this, but it repeated the
comparison of derpNum and c.myDerp after c.myDerp had been
updated, so it never executed.
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
Before, endpoint updates were constantly being interrupted and resumed
on Linux due to tons of LinkChange messages from over-zealous Linux
netlink messages (from router_linux.go)
Now that endpoint updates are fast and bounded in time anyway, just
let them run to completion, but note that another needs to be
scheduled after.
Now logs went from pages of noise to just:
root@taildoc:~# grep -i -E 'stun|endpoint update' log
2020/03/13 08:51:29 magicsock.Conn: starting endpoint update (initial)
2020/03/13 08:51:30 magicsock.Conn.ReSTUN: endpoint update active, need another later ("link-change-minor")
2020/03/13 08:51:31 magicsock.Conn: starting endpoint update (link-change-minor)
2020/03/13 08:51:31 magicsock.Conn.ReSTUN: endpoint update active, need another later ("link-change-minor")
2020/03/13 08:51:33 magicsock.Conn: starting endpoint update (link-change-minor)
2020/03/13 08:51:33 magicsock.Conn.ReSTUN: endpoint update active, need another later ("link-change-minor")
2020/03/13 08:51:35 magicsock.Conn: starting endpoint update (link-change-minor)
2020/03/13 08:51:35 magicsock.Conn.ReSTUN: endpoint update active, need another later ("link-change-minor")
Or, seen in another run:
2020/03/13 08:45:41 magicsock.Conn: starting endpoint update (periodic)
2020/03/13 08:46:09 magicsock.Conn: starting endpoint update (periodic)
2020/03/13 08:46:21 magicsock.Conn: starting endpoint update (link-change-major)
2020/03/13 08:46:37 magicsock.Conn: starting endpoint update (periodic)
2020/03/13 08:47:05 magicsock.Conn: starting endpoint update (periodic)
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
The TODO above derphttp.NewClient suggests it does network I/O,
but the derphttp client connects lazily and so creating one is
very cheap.
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
It used to make assumptions based on having Anycast IPs that are super
near. Now we're intentionally going to a bunch of different distant
IPs to measure latency.
Also, optimize how the hairpin detection works. No need to STUN on
that socket. Just use that separate socket for sending, once we know
the other UDP4 socket's endpoint. The trick is: make our test probe
also a STUN packet, so it fits through magicsock's existing STUN
routing.
This drops netcheck from ~5 seconds to ~250-500ms.
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Failure to do this leads to fd exhaustion at -count=10000,
and increasingly poor execution north of -count=100.
Signed-off-by: David Anderson <danderson@tailscale.com>
Failure to do so triggers either a data race or a panic
in the testing package, due to racey use of t.Logf.
Signed-off-by: David Anderson <danderson@tailscale.com>
Basically, don't trust the OS-level link monitor to only tell you
interesting things. Sanity check it.
Also, move the interfaces package into the net directory now that we
have it.
This was (presumably) missing from wgengine because the
interactions between magicsock and wireguard-go meant that the
shutdown never worked. Now those are fixed, actually shut down.
Fixes occasional flake in expanded ipn/e2e_test.
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
The device name "tailscale0" will be used for all platforms except for
OpenBSD where "tun" is enforced by the kernel. `CreateTUN()` in
`wireguard-go` will select the next available "tunX" device name on the
OpenBSD system.
Signed-off-by: Martin Baillie <martin@baillie.email>
The UDP reader goroutine was clobbering `n` and `err` from the
main goroutine, whose accesses are not synchronized the way `b` is.
Signed-off-by: David Anderson <danderson@tailscale.com>
