add plugin system

admission/admission.go

@@ -13,6 +13,7 @@ import (
 	"github.com/go-gost/core/logger"
 	"github.com/go-gost/x/internal/loader"
 	"github.com/go-gost/x/internal/matcher"
+	"google.golang.org/grpc"
 )
 
 type options struct {
@@ -21,6 +22,7 @@ type options struct {
 	fileLoader  loader.Loader
 	redisLoader loader.Loader
 	httpLoader  loader.Loader
+	client      *grpc.ClientConn
 	period      time.Duration
 	logger      logger.Logger
 }
@@ -63,6 +65,12 @@ func HTTPLoaderOption(httpLoader loader.Loader) Option {
 	}
 }
 
+func PluginConnOption(c *grpc.ClientConn) Option {
+	return func(opts *options) {
+		opts.client = c
+	}
+}
+
 func LoggerOption(logger logger.Logger) Option {
 	return func(opts *options) {
 		opts.logger = logger
@@ -101,7 +109,7 @@ func NewAdmission(opts ...Option) admission_pkg.Admission {
 	return p
 }
 
-func (p *admission) Admit(addr string) bool {
+func (p *admission) Admit(ctx context.Context, addr string) bool {
 	if addr == "" || p == nil {
 		return true
 	}

admission/plugin.go

@@ -0,0 +1,56 @@
+package admission
+
+import (
+	"context"
+
+	admission_pkg "github.com/go-gost/core/admission"
+	"github.com/go-gost/plugin/admission/proto"
+	xlogger "github.com/go-gost/x/logger"
+)
+
+type pluginAdmission struct {
+	client  proto.AdmissionClient
+	options options
+}
+
+// NewPluginAdmission creates a plugin admission.
+func NewPluginAdmission(opts ...Option) admission_pkg.Admission {
+	var options options
+	for _, opt := range opts {
+		opt(&options)
+	}
+	if options.logger == nil {
+		options.logger = xlogger.Nop()
+	}
+
+	p := &pluginAdmission{
+		options: options,
+	}
+	if options.client != nil {
+		p.client = proto.NewAdmissionClient(options.client)
+	}
+	return p
+}
+
+func (p *pluginAdmission) Admit(ctx context.Context, addr string) bool {
+	if p.client == nil {
+		return false
+	}
+
+	r, err := p.client.Admit(ctx,
+		&proto.AdmissionRequest{
+			Addr: addr,
+		})
+	if err != nil {
+		p.options.logger.Error(err)
+		return false
+	}
+	return r.Ok
+}
+
+func (p *pluginAdmission) Close() error {
+	if p.options.client != nil {
+		return p.options.client.Close()
+	}
+	return nil
+}

admission/wrapper/conn.go

@@ -1,6 +1,7 @@
 package wrapper
 
 import (
+	"context"
 	"errors"
 	"io"
 	"net"
@@ -33,7 +34,7 @@ func WrapConn(admission admission.Admission, c net.Conn) net.Conn {
 
 func (c *serverConn) Read(b []byte) (n int, err error) {
 	if c.admission != nil &&
-		!c.admission.Admit(c.RemoteAddr().String()) {
+		!c.admission.Admit(context.Background(), c.RemoteAddr().String()) {
 		err = io.EOF
 		return
 	}
@@ -79,7 +80,7 @@ func (c *packetConn) ReadFrom(p []byte) (n int, addr net.Addr, err error) {
 		}
 
 		if c.admission != nil &&
-			!c.admission.Admit(addr.String()) {
+			!c.admission.Admit(context.Background(), addr.String()) {
 			continue
 		}
 
@@ -143,7 +144,7 @@ func (c *udpConn) ReadFrom(p []byte) (n int, addr net.Addr, err error) {
 			return
 		}
 		if c.admission != nil &&
-			!c.admission.Admit(addr.String()) {
+			!c.admission.Admit(context.Background(), addr.String()) {
 			continue
 		}
 		return
@@ -158,7 +159,7 @@ func (c *udpConn) ReadFromUDP(b []byte) (n int, addr *net.UDPAddr, err error) {
 				return
 			}
 			if c.admission != nil &&
-				!c.admission.Admit(addr.String()) {
+				!c.admission.Admit(context.Background(), addr.String()) {
 				continue
 			}
 			return
@@ -176,7 +177,7 @@ func (c *udpConn) ReadMsgUDP(b, oob []byte) (n, oobn, flags int, addr *net.UDPAd
 				return
 			}
 			if c.admission != nil &&
-				!c.admission.Admit(addr.String()) {
+				!c.admission.Admit(context.Background(), addr.String()) {
 				continue
 			}
 			return

admission/wrapper/listener.go

@@ -1,6 +1,7 @@
 package wrapper
 
 import (
+	"context"
 	"net"
 
 	"github.com/go-gost/core/admission"
@@ -28,7 +29,7 @@ func (ln *listener) Accept() (net.Conn, error) {
 			return nil, err
 		}
 		if ln.admission != nil &&
-			!ln.admission.Admit(c.RemoteAddr().String()) {
+			!ln.admission.Admit(context.Background(), c.RemoteAddr().String()) {
 			c.Close()
 			continue
 		}