mirrors/tailscale
1
0
Fork 0
Code Issues Pull Requests Projects Wiki Activity

wgengine: wrap tun.Device to support filtering and packet injection (#358)

Browse Source 
Right now, filtering and packet injection in wgengine depend
on a patch to wireguard-go that probably isn't suitable for upstreaming.

This need not be the case: wireguard-go/tun.Device is an interface.
For example, faketun.go implements it to mock a TUN device for testing.

This patch implements the same interface to provide filtering
and packet injection at the tunnel device level,
at which point the wireguard-go patch should no longer be necessary.

This patch has the following performance impact on i7-7500U @ 2.70GHz,
tested in the following namespace configuration:
┌────────────────┐    ┌─────────────────────────────────┐     ┌────────────────┐
│      $ns1      │    │               $ns0              │     │      $ns2      │
│    client0     │    │      tailcontrol, logcatcher    │     │     client1    │
│  ┌─────┐       │    │  ┌──────┐         ┌──────┐      │     │  ┌─────┐       │
│  │vethc│───────┼────┼──│vethrc│         │vethrs│──────┼─────┼──│veths│       │
│  ├─────┴─────┐ │    │  ├──────┴────┐    ├──────┴────┐ │     │  ├─────┴─────┐ │
│  │10.0.0.2/24│ │    │  │10.0.0.1/24│    │10.0.1.1/24│ │     │  │10.0.1.2/24│ │
│  └───────────┘ │    │  └───────────┘    └───────────┘ │     │  └───────────┘ │
└────────────────┘    └─────────────────────────────────┘     └────────────────┘
Before:
---------------------------------------------------
| TCP send               | UDP send               |
|------------------------|------------------------|
| 557.0 (±8.5) Mbits/sec | 3.03 (±0.02) Gbits/sec |
---------------------------------------------------
After:
---------------------------------------------------
| TCP send               | UDP send               |
|------------------------|------------------------|
| 544.8 (±1.6) Mbits/sec | 3.13 (±0.02) Gbits/sec |
---------------------------------------------------
The impact on receive performance is similar.

Signed-off-by: Dmytro Shynkevych <dmytro@tailscale.com>
This commit is contained in:
Dmytro Shynkevych
2020-05-13 09:16:17 -04:00
committed by GitHub
parent 9ccbcda612
commit 33b2f30cea
7 changed files with 355 additions and 130 deletions
Download Patch File Download Diff File Expand all files Collapse all files

5
wgengine/watchdog_test.go
View File

@ -12,6 +12,7 @@ import (
"time"
"tailscale.com/wgengine/router"
"tailscale.com/wgengine/tstun"
)
func TestWatchdog(t *testing.T) {
@ -19,7 +20,7 @@ func TestWatchdog(t *testing.T) {
t.Run("default watchdog does not fire", func(t *testing.T) {
t.Parallel()
tun := NewFakeTun()
tun := tstun.WrapTUN(t.Logf, tstun.NewFakeTUN())
e, err := NewUserspaceEngineAdvanced(t.Logf, tun, router.NewFake, 0)
if err != nil {
t.Fatal(err)
@ -36,7 +37,7 @@ func TestWatchdog(t *testing.T) {
t.Run("watchdog fires on blocked getStatus", func(t *testing.T) {
t.Parallel()
tun := NewFakeTun()
tun := tstun.WrapTUN(t.Logf, tstun.NewFakeTUN())
e, err := NewUserspaceEngineAdvanced(t.Logf, tun, router.NewFake, 0)
if err != nil {
t.Fatal(err)