gost/pkg/handler/socks/v4/handler.go
2021-11-09 23:34:19 +08:00

161 lines
3.6 KiB
Go

package v4
import (
"context"
"net"
"time"
"github.com/go-gost/gosocks4"
"github.com/go-gost/gost/pkg/auth"
"github.com/go-gost/gost/pkg/bypass"
"github.com/go-gost/gost/pkg/chain"
"github.com/go-gost/gost/pkg/handler"
"github.com/go-gost/gost/pkg/logger"
md "github.com/go-gost/gost/pkg/metadata"
"github.com/go-gost/gost/pkg/registry"
)
func init() {
registry.RegisterHandler("socks4", NewHandler)
registry.RegisterHandler("socks4a", NewHandler)
}
type socks4Handler struct {
chain *chain.Chain
bypass bypass.Bypass
logger logger.Logger
md metadata
}
func NewHandler(opts ...handler.Option) handler.Handler {
options := &handler.Options{}
for _, opt := range opts {
opt(options)
}
return &socks4Handler{
chain: options.Chain,
bypass: options.Bypass,
logger: options.Logger,
}
}
func (h *socks4Handler) Init(md md.Metadata) (err error) {
return h.parseMetadata(md)
}
func (h *socks4Handler) Handle(ctx context.Context, conn net.Conn) {
defer conn.Close()
start := time.Now()
h.logger = h.logger.WithFields(map[string]interface{}{
"remote": conn.RemoteAddr().String(),
"local": conn.LocalAddr().String(),
})
h.logger.Infof("%s <> %s", conn.RemoteAddr(), conn.LocalAddr())
defer func() {
h.logger.WithFields(map[string]interface{}{
"duration": time.Since(start),
}).Infof("%s >< %s", conn.RemoteAddr(), conn.LocalAddr())
}()
if h.md.readTimeout > 0 {
conn.SetReadDeadline(time.Now().Add(h.md.readTimeout))
}
req, err := gosocks4.ReadRequest(conn)
if err != nil {
h.logger.Error(err)
return
}
h.logger.Debug(req)
conn.SetReadDeadline(time.Time{})
if h.md.authenticator != nil &&
!h.md.authenticator.Authenticate(string(req.Userid), "") {
resp := gosocks4.NewReply(gosocks4.RejectedUserid, nil)
resp.Write(conn)
h.logger.Debug(resp)
return
}
switch req.Cmd {
case gosocks4.CmdConnect:
h.handleConnect(ctx, conn, req)
case gosocks4.CmdBind:
h.handleBind(ctx, conn, req)
default:
h.logger.Errorf("unknown cmd: %d", req.Cmd)
}
}
func (h *socks4Handler) handleConnect(ctx context.Context, conn net.Conn, req *gosocks4.Request) {
addr := req.Addr.String()
h.logger = h.logger.WithFields(map[string]interface{}{
"dst": addr,
})
h.logger.Infof("%s >> %s", conn.RemoteAddr(), addr)
if h.bypass != nil && h.bypass.Contains(addr) {
resp := gosocks4.NewReply(gosocks4.Rejected, nil)
resp.Write(conn)
h.logger.Debug(resp)
h.logger.Info("bypass: ", addr)
return
}
r := (&handler.Router{}).
WithChain(h.chain).
WithRetry(h.md.retryCount).
WithLogger(h.logger)
cc, err := r.Dial(ctx, "tcp", addr)
if err != nil {
resp := gosocks4.NewReply(gosocks4.Failed, nil)
resp.Write(conn)
h.logger.Debug(resp)
return
}
defer cc.Close()
resp := gosocks4.NewReply(gosocks4.Granted, nil)
if err := resp.Write(conn); err != nil {
h.logger.Error(err)
return
}
h.logger.Debug(resp)
t := time.Now()
h.logger.Infof("%s <-> %s", conn.RemoteAddr(), addr)
handler.Transport(conn, cc)
h.logger.
WithFields(map[string]interface{}{
"duration": time.Since(t),
}).
Infof("%s >-< %s", conn.RemoteAddr(), addr)
}
func (h *socks4Handler) handleBind(ctx context.Context, conn net.Conn, req *gosocks4.Request) {
// TODO: bind
}
func (h *socks4Handler) parseMetadata(md md.Metadata) (err error) {
if v, _ := md.Get(authsKey).([]interface{}); len(v) > 0 {
authenticator := auth.NewLocalAuthenticator(nil)
for _, auth := range v {
if v, _ := auth.(string); v != "" {
authenticator.Add(v, "")
}
}
h.md.authenticator = authenticator
}
h.md.readTimeout = md.GetDuration(readTimeout)
h.md.retryCount = md.GetInt(retryCount)
return
}