WireGuard proxy: Refactor (#6287)

And https://github.com/XTLS/Xray-core/pull/6303#issuecomment-4669158076

Fixes https://github.com/XTLS/Xray-core/issues/6257

proxy/hysteria/client.go

@@ -29,6 +29,13 @@ type Client struct {
 }
 
 func NewClient(ctx context.Context, config *ClientConfig) (*Client, error) {
+	v := core.MustFromContext(ctx)
+	p := v.GetFeature(policy.ManagerType()).(policy.Manager)
+
+	streamSettings := session.StreamSettingsFromContext(ctx).(*internet.MemoryStreamConfig)
+	if _, ok := streamSettings.ProtocolSettings.(*hysteria.Config); !ok {
+		return nil, errors.New("not hysteria transport")
+	}
 	if config.Server == nil {
 		return nil, errors.New(`no target server found`)
 	}
@@ -37,12 +44,10 @@ func NewClient(ctx context.Context, config *ClientConfig) (*Client, error) {
 		return nil, errors.New("failed to get server spec").Base(err)
 	}
 
-	v := core.MustFromContext(ctx)
-	client := &Client{
+	return &Client{
 		server:        server,
-		policyManager: v.GetFeature(policy.ManagerType()).(policy.Manager),
-	}
-	return client, nil
+		policyManager: p,
+	}, nil
 }
 
 func (c *Client) Process(ctx context.Context, link *transport.Link, dialer internet.Dialer) error {

proxy/hysteria/server.go

@@ -16,6 +16,7 @@ import (
 	"github.com/xtls/xray-core/features/routing"
 	"github.com/xtls/xray-core/proxy/hysteria/account"
 	"github.com/xtls/xray-core/transport"
+	"github.com/xtls/xray-core/transport/internet"
 	"github.com/xtls/xray-core/transport/internet/hysteria"
 	"github.com/xtls/xray-core/transport/internet/stat"
 )
@@ -27,6 +28,14 @@ type Server struct {
 }
 
 func NewServer(ctx context.Context, config *ServerConfig) (*Server, error) {
+	v := core.MustFromContext(ctx)
+	p := v.GetFeature(policy.ManagerType()).(policy.Manager)
+
+	streamSettings := session.StreamSettingsFromContext(ctx).(*internet.MemoryStreamConfig)
+	if _, ok := streamSettings.ProtocolSettings.(*hysteria.Config); !ok {
+		return nil, errors.New("not hysteria transport")
+	}
+
 	validator := account.NewValidator()
 	for _, user := range config.Users {
 		u, err := user.ToMemoryUser()
@@ -39,14 +48,11 @@ func NewServer(ctx context.Context, config *ServerConfig) (*Server, error) {
 		}
 	}
 
-	v := core.MustFromContext(ctx)
-	s := &Server{
+	return &Server{
 		config:        config,
 		validator:     validator,
-		policyManager: v.GetFeature(policy.ManagerType()).(policy.Manager),
-	}
-
-	return s, nil
+		policyManager: p,
+	}, nil
 }
 
 func (s *Server) HysteriaInboundValidator() *account.Validator {