slimming/tap.go
2022-08-25 10:12:43 +08:00

144 lines
2.6 KiB
Go

package main
import (
"context"
"log"
gen "slimming/proto/gen"
"time"
"github.com/songgao/packets/ethernet"
"github.com/songgao/water"
"google.golang.org/grpc"
"google.golang.org/grpc/credentials/insecure"
)
type NetCard struct {
FrameChan chan [][]byte
ifce *water.Interface
cli *RPCClient
server *RPCServer
}
type RPCClient struct {
FrameChan chan [][]byte
conn *grpc.ClientConn
}
func (cli *RPCClient) connect() {
log.Println("rpcclient start")
defer log.Println("rpcclient exit")
conn, err := grpc.Dial(*othersAddr,
grpc.WithTransportCredentials(insecure.NewCredentials()),
)
if err != nil {
log.Printf("did not connect: %v", err)
return
}
cli.conn = conn
go cli.run()
}
func (cli *RPCClient) run() {
c := gen.NewFrameServiceClient(cli.conn)
ctx, cancel := context.WithTimeout(context.Background(), time.Second*10)
defer cancel()
stream, err := c.SendFrames(ctx)
if err != nil {
panic(err)
}
for {
// Contact the server and print out its response.
// 发到对面的网卡
err = stream.Send(&gen.Request{
Frames: <-cli.FrameChan,
})
if err != nil {
panic(err)
}
}
}
func (nc *NetCard) Run() {
go nc.runRead()
go nc.runWrite()
// go nc.cli.run()
nc.server.run()
}
func NewNetCard() *NetCard {
config := water.Config{
DeviceType: water.TAP,
}
config.Name = "stap"
ifce, err := water.New(config)
if err != nil {
log.Fatal(err)
}
nc := &NetCard{
FrameChan: make(chan [][]byte, 2000),
ifce: ifce,
cli: &RPCClient{FrameChan: make(chan [][]byte, 2000)},
}
nc.server = newRPCServer(nc)
return nc
}
func (nc *NetCard) runRead() {
var ifce *water.Interface = nc.ifce
var ticker time.Ticker = *time.NewTicker(time.Millisecond * 20)
for {
var framesBytes [][]byte
for range ticker.C {
var rframe ethernet.Frame
rframe.Resize(1500)
n, err := ifce.Read([]byte(rframe))
if err != nil {
log.Fatal(err)
}
rframe = rframe[:n]
framesBytes = append(framesBytes, []byte(rframe))
}
if len(framesBytes) > 0 {
if nc.cli.conn == nil {
nc.cli.connect()
}
if nc.cli.conn != nil {
nc.cli.FrameChan <- framesBytes // 网卡数据 发到对方
}
}
// 写到grpc服务
// log.Printf("Dst: %s\n", rframe.Destination()[0:4])
// log.Printf("Src: %s\n", rframe.Source()[0:4])
// log.Printf("Ethertype: % x\n", rframe.Ethertype())
// log.Printf("Payload: % x\n", rframe.Payload())
}
}
func (nc *NetCard) runWrite() {
var ifce *water.Interface = nc.ifce
for wframes := range nc.FrameChan {
for _, wframe := range wframes {
_, err := ifce.Write(wframe)
if err != nil {
panic(err)
}
}
}
}