gost/pkg/handler/forward/local/handler.go
2022-02-27 22:32:15 +08:00

116 lines
2.5 KiB
Go

package local
import (
"context"
"fmt"
"net"
"time"
"github.com/go-gost/gost/pkg/chain"
"github.com/go-gost/gost/pkg/handler"
md "github.com/go-gost/gost/pkg/metadata"
"github.com/go-gost/gost/pkg/registry"
)
func init() {
registry.HandlerRegistry().Register("tcp", NewHandler)
registry.HandlerRegistry().Register("udp", NewHandler)
registry.HandlerRegistry().Register("forward", NewHandler)
}
type forwardHandler struct {
group *chain.NodeGroup
router *chain.Router
md metadata
options handler.Options
}
func NewHandler(opts ...handler.Option) handler.Handler {
options := handler.Options{}
for _, opt := range opts {
opt(&options)
}
return &forwardHandler{
options: options,
}
}
func (h *forwardHandler) Init(md md.Metadata) (err error) {
if err = h.parseMetadata(md); err != nil {
return
}
if h.group == nil {
// dummy node used by relay connector.
h.group = chain.NewNodeGroup(&chain.Node{Name: "dummy", Addr: ":0"})
}
h.router = &chain.Router{
Retries: h.options.Retries,
Chain: h.options.Chain,
Resolver: h.options.Resolver,
Hosts: h.options.Hosts,
Logger: h.options.Logger,
}
return
}
// Forward implements handler.Forwarder.
func (h *forwardHandler) Forward(group *chain.NodeGroup) {
h.group = group
}
func (h *forwardHandler) Handle(ctx context.Context, conn net.Conn) {
defer conn.Close()
start := time.Now()
log := h.options.Logger.WithFields(map[string]any{
"remote": conn.RemoteAddr().String(),
"local": conn.LocalAddr().String(),
})
log.Infof("%s <> %s", conn.RemoteAddr(), conn.LocalAddr())
defer func() {
log.WithFields(map[string]any{
"duration": time.Since(start),
}).Infof("%s >< %s", conn.RemoteAddr(), conn.LocalAddr())
}()
target := h.group.Next()
if target == nil {
log.Error("no target available")
return
}
network := "tcp"
if _, ok := conn.(net.PacketConn); ok {
network = "udp"
}
log = log.WithFields(map[string]any{
"dst": fmt.Sprintf("%s/%s", target.Addr, network),
})
log.Infof("%s >> %s", conn.RemoteAddr(), target.Addr)
cc, err := h.router.Dial(ctx, network, target.Addr)
if err != nil {
log.Error(err)
// TODO: the router itself may be failed due to the failed node in the router,
// the dead marker may be a wrong operation.
target.Marker.Mark()
return
}
defer cc.Close()
target.Marker.Reset()
t := time.Now()
log.Infof("%s <-> %s", conn.RemoteAddr(), target.Addr)
handler.Transport(conn, cc)
log.WithFields(map[string]any{
"duration": time.Since(t),
}).Infof("%s >-< %s", conn.RemoteAddr(), target.Addr)
}