While the code was correct, I broke it during a refactoring and
tests didn't detect it. This fixes that glitch.
Signed-off-by: David Anderson <danderson@tailscale.com>
Doesn't materially affect benchmarks, but shrinks match6 by 30 instructions
and halves memory loads.
Part of #19.
Signed-off-by: David Anderson <danderson@tailscale.com>
The packet filter still rejects all IPv6, but decodes enough from v6
packets to do something smarter in a followup.
name time/op
Decode/tcp4-8 28.8ns ± 2%
Decode/tcp6-8 20.6ns ± 1%
Decode/udp4-8 28.2ns ± 1%
Decode/udp6-8 20.0ns ± 6%
Decode/icmp4-8 21.7ns ± 2%
Decode/icmp6-8 14.1ns ± 2%
Decode/unknown-8 9.43ns ± 2%
Signed-off-by: David Anderson <danderson@tailscale.com>
The goal is to move some of the shenanigans we have elsewhere into the filter
package, so that all the weird things to do with poking at the filter is in
a single place, behind clean APIs.
Signed-off-by: David Anderson <danderson@tailscale.com>
We still use the packet.* alloc-free types in the data path, but
the compilation from netaddr to packet happens within the filter
package.
Signed-off-by: David Anderson <danderson@tailscale.com>
This makes it easier to integrate this version math into a submodule-ful
world. We'll continue to have regular git tags that parallel the information
in VERSION, so that builds out of this repository behave the same.
Signed-off-by: David Anderson <danderson@tailscale.com>
Amazingly, there doesn't seem to be a documented way of updating network
configuration programmatically in a way that Windows takes notice of.
The naturopathic remedy for this is to invoke ipconfig /registerdns, which
does a variety of harmless things and also invokes the private API that
tells windows to notice new adapter settings. This makes our DNS config
changes stick within a few seconds of us setting them.
If we're invoking a shell command anyway, why futz with the registry at
all? Because netsh has no command for changing the DNS suffix list, and
its commands for setting resolvers requires parsing its output and
keeping track of which server is in what index. Amazingly, twiddling
the registry directly is the less painful option.
Fixes#853.
Signed-off-by: David Anderson <danderson@tailscale.com>
When building with redo, also include the git commit hash
from the proprietary repo, so that we have a precise commit
that identifies all build info (including Go toolchain version).
Add a top-level build script demonstrating to downstream distros
how to burn the right information into builds.
Adjust `tailscale version` to print commit hashes when available.
Fixes#841.
Signed-off-by: David Anderson <danderson@tailscale.com>
Also replaces the IPv6Overlay bool with use of DebugFlags, since
it's currently an experimental configuration.
Signed-off-by: David Anderson <danderson@tailscale.com>
Gracefully skips touching the v6 NAT table on systems that don't have
it, and doesn't configure IPv6 at all if IPv6 is globally disabled.
Signed-off-by: David Anderson <danderson@tailscale.com>
Also remove rebinding logic from the windows router. Magicsock will
instead rebind based on link change signals.
Signed-off-by: David Anderson <danderson@tailscale.com>
Strictly speaking, we don't know that it's a wireguard packet, just that
it doesn't look like a disco packet.
Signed-off-by: David Anderson <danderson@tailscale.com>
SIGPIPE can be generated when CLIs disconnect from tailscaled. This
should not terminate the process.
Signed-off-by: David Anderson <danderson@tailscale.com>
tailscaled receives a SIGPIPE when CLIs disconnect from it. We shouldn't
shut down in that case.
This reverts commit 43b271cb26.
Signed-off-by: David Anderson <danderson@tailscale.com>
ORder of operations to trigger a problem:
- Start an already authed tailscaled, verify you can ping stuff.
- Run `tailscale up`. Notice you can no longer ping stuff.
The problem is that `tailscale up` stops the IPN state machine before
restarting it, which zeros out the packet filter but _not_ the packet
filter hash. Then, upon restarting IPN, the uncleared hash incorrectly
makes the code conclude that the filter doesn't need updating, and so
we stay with a zero filter (reject everything) for ever.
The fix is simply to update the filterHash correctly in all cases,
so that running -> stopped -> running correctly changes the filter
at every transition.
Signed-off-by: David Anderson <danderson@tailscale.com>
There is a race in natlab where we might start shutdown while natlab is still running
a goroutine or two to deliver packets. This adds a small grace period to try and receive
it before continuing shutdown.
Signed-off-by: David Anderson <danderson@tailscale.com>
The first packet to transit may take several seconds to do so, because
setup rates in wgengine may result in the initial WireGuard handshake
init to get dropped. So, we have to wait at least long enough for a
retransmit to correct the fault.
Signed-off-by: David Anderson <danderson@tailscale.com>
Active discovery lets us introspect the state of the network stack precisely
enough that it's unnecessary, and dropping the initial DERP packets greatly
slows down tests. Additionally, it's unrealistic since our production network
will never deliver _only_ discovery packets, it'll be all or nothing.
Signed-off-by: David Anderson <danderson@tailscale.com>
Uses natlab only, because the point of this active discovery test is going to be
that it should get through a lot of obstacles.
Signed-off-by: David Anderson <danderson@tailscale.com>
LANs are authoritative for their prefixes, so we should not bounce
packets back and forth to the default gateway in that case.
Signed-off-by: David Anderson <danderson@tailscale.com>
We originally picked those numbers somewhat at random, but with the idea
that 8 is a traditionally lucky number in Chinese culture. Unfortunately,
"88" is also neo-nazi shorthand language.
Use 52 instead, because those are the digits above the letters
"TS" (tailscale) on a qwerty keyboard, so we're unlikely to collide with
other users. 5, 2 and 52 are also pleasantly culturally meaningless.
Signed-off-by: David Anderson <danderson@tailscale.com>
The new interface lets implementors more precisely distinguish
local traffic from forwarded traffic, and applies different
forwarding logic within Machines for each type. This allows
Machines to be packet forwarders, which didn't quite work
with the implementation of Inject.
Signed-off-by: David Anderson <danderson@tailscale.com>
The test demonstrates that magicsock can traverse two stateful
firewalls facing each other, that each require localhost to
initiate connections.
Signed-off-by: David Anderson <danderson@tailscale.com>
HandlePacket and Inject now receive/take Packets. This is a handy
container for the packet, and the attached Trace method can be used
to print traces from custom packet handlers that integrate nicely
with natlab's internal traces.
Signed-off-by: David Anderson <danderson@tailscale.com>
The firewall provides a ProcessPacket handler, and implements an
address-and-port endpoint dependent firewall that allows all
traffic to egress from the trusted interface, and only allows
inbound traffic if corresponding outbound traffic was previously
seen.
Signed-off-by: David Anderson <danderson@tailscale.com>
Requires a bunch of refactoring so that Networks only ever
refer to Interfaces that have been attached to them, and
Interfaces know about both their Network and Machine.
Signed-off-by: David Anderson <danderson@tailscale.com>
This is a prelude to adding more fields, which would otherwise
become more unnamed function params.
Signed-off-by: David Anderson <danderson@tailscale.com>
It's just a config wrapper that passes "use less memory at the
expense of compression" parameters by default, so that we don't
accidentally construct resource-hungry (de)compressors.
Also includes a benchmark that measures the memory cost of the
small variants vs. the stock variants. The savings are significant
on both compressors (~8x less memory) and decompressors (~1.4x less,
not including the savings from the significantly smaller
window on the compression side - with those savings included it's
more like ~140x smaller).
BenchmarkSmallEncoder-8 56174 19354 ns/op 31 B/op 0 allocs/op
BenchmarkSmallEncoderWithBuild-8 2900 382940 ns/op 1746547 B/op 36 allocs/op
BenchmarkStockEncoder-8 48921 25761 ns/op 286 B/op 0 allocs/op
BenchmarkStockEncoderWithBuild-8 426 2630241 ns/op 13843842 B/op 124 allocs/op
BenchmarkSmallDecoder-8 123814 9344 ns/op 0 B/op 0 allocs/op
BenchmarkSmallDecoderWithBuild-8 41547 27455 ns/op 27694 B/op 31 allocs/op
BenchmarkStockDecoder-8 129832 9417 ns/op 1 B/op 0 allocs/op
BenchmarkStockDecoderWithBuild-8 25561 51751 ns/op 39607 B/op 92 allocs/op
Signed-off-by: David Anderson <danderson@tailscale.com>
David Anderson
