In particular, this is designed to catch the case where a
HandshakeInitiation packet is sent out but the intermediate NATs
have not been primed, so the packet passes over DERP.
In that case, the HandshakeResponse also comes back over DERP,
and the connection proceeds via DERP without ever trying to punch
through the NAT.
With this change, the HandshakeResponse (which was sprayed out
and so primed one NAT) triggers an UpdateDst, which triggers
the extra spray logic.
(For this to work, there has to be an initial supply of packets
to send on to a peer for the three seconds following a handshake.
The source of these packets is left as a future exercise.)
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
I broke an invariant in 11048b8932 (it was even nicely
documented then).
Also clean up the test a bit from while I was debugging it.
Fixes#84
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Prefs has become a heavy object with non-memcpy copy
semantics. We should not pass such a thing by value.
Signed-off-by: David Anderson <dave@natulte.net>
This is the first, and easier, part of incremental wireguard-go
reconfiguration. It means that a new node appearing on the
network does not cause all existing nodes to re-handshake with
the other nodes they are talking to.
(This code has been running on hello.ipn.dev for a few weeks and
peers have successfully reconnected to it through many network
map updates.)
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
relaynode itself is not long for this world, deprecated in favour of
tailscale/tailscaled. But now that the control server supports central
distribution of packet filters, let's actually take advantage of it in
a final, backward compatible release of relaynode.
staticcheck defaults to running with no tags set, which only
works if redo hasn't run and generated ver.go. If it has,
we end up with a redeclaration conflict.
Signed-off-by: David Anderson <dave@natulte.net>
The autoselection should pick sensible paths for all of:
- Windows (LocalAppData)
- Mac (Library/Caches)
- Unix user (XDG_CACHE_DIR)
- Linux systemd service (CACHE_DIRECTORY)
As a last resort, if cache dir lookup fails, plops sufficiently
uniquely named files into the current working directory.
Signed-off-by: David Anderson <dave@natulte.net>
We can't rely on a frontend to provide a control
server URL, so this naturally belongs in server-persisted
state.
Signed-off-by: David Anderson <dave@natulte.net>
Port number has to be by itself for substitution to work.
Disabling the restart rate-limiting has to be in [Unit] not
[Service].
Signed-off-by: David Anderson <dave@natulte.net>
On unix, we want to provide a full path to the desired unix socket.
On windows, currently we want to provide a TCP port, but someday
we'll also provide a "path-ish" object for a named pipe.
For now, simplify the API down to exactly a path and a TCP port.
Signed-off-by: David Anderson <dave@natulte.net>
