fix proxy protocol

handler/socks/v4/handler.go

@@ -12,6 +12,7 @@ import (
 	md "github.com/go-gost/core/metadata"
 	"github.com/go-gost/gosocks4"
 	netpkg "github.com/go-gost/x/internal/net"
+	sx "github.com/go-gost/x/internal/util/selector"
 	"github.com/go-gost/x/registry"
 )
 
@@ -123,6 +124,11 @@ func (h *socks4Handler) handleConnect(ctx context.Context, conn net.Conn, req *g
 		return resp.Write(conn)
 	}
 
+	switch h.md.hash {
+	case "host":
+		ctx = sx.ContextWithHash(ctx, &sx.Hash{Source: addr})
+	}
+
 	cc, err := h.router.Dial(ctx, "tcp", addr)
 	if err != nil {
 		resp := gosocks4.NewReply(gosocks4.Failed, nil)

handler/socks/v4/metadata.go

@@ -9,13 +9,16 @@ import (
 
 type metadata struct {
 	readTimeout time.Duration
+	hash        string
 }
 
 func (h *socks4Handler) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		readTimeout = "readTimeout"
+		hash        = "hash"
 	)
 
 	h.md.readTimeout = mdutil.GetDuration(md, readTimeout)
+	h.md.hash = mdutil.GetString(md, hash)
 	return
 }