Added NotificationHandler assignment via SocketConfig.

sctp.go

@@ -636,8 +636,9 @@ func (c *SCTPConn) SetWriteDeadline(t time.Time) error {
 }
 
 type SCTPListener struct {
-	fd int
-	m  sync.Mutex
+	fd                  int
+	m                   sync.Mutex
+	notificationHandler NotificationHandler
 }
 
 func (ln *SCTPListener) Addr() net.Addr {
@@ -723,15 +724,16 @@ type SocketConfig struct {
 	// If Control is not nil it is called after the socket is created but before
 	// it is bound or connected.
 	Control func(network, address string, c syscall.RawConn) error
-
+	// NotificationHandler defines actions taken on received notifications when MSG_NOTIFICATION flag is set.
+	NotificationHandler NotificationHandler
 	// InitMsg is the options to send in the initial SCTP message
 	InitMsg InitMsg
 }
 
 func (cfg *SocketConfig) Listen(net string, laddr *SCTPAddr) (*SCTPListener, error) {
-	return listenSCTPExtConfig(net, laddr, cfg.InitMsg, cfg.Control)
+	return listenSCTPExtConfig(net, laddr, cfg.InitMsg, cfg.Control, cfg.NotificationHandler)
 }
 
 func (cfg *SocketConfig) Dial(net string, laddr, raddr *SCTPAddr) (*SCTPConn, error) {
-	return dialSCTPExtConfig(net, laddr, raddr, cfg.InitMsg, cfg.Control)
+	return dialSCTPExtConfig(net, laddr, raddr, cfg.InitMsg, cfg.Control, cfg.NotificationHandler)
 }

sctp_linux.go

@@ -174,11 +174,11 @@ func ListenSCTP(net string, laddr *SCTPAddr) (*SCTPListener, error) {
 
 // ListenSCTPExt - start listener on specified address/port with given SCTP options
 func ListenSCTPExt(network string, laddr *SCTPAddr, options InitMsg) (*SCTPListener, error) {
-	return listenSCTPExtConfig(network, laddr, options, nil)
+	return listenSCTPExtConfig(network, laddr, options, nil, nil)
 }
 
 // listenSCTPExtConfig - start listener on specified address/port with given SCTP options and socket configuration
-func listenSCTPExtConfig(network string, laddr *SCTPAddr, options InitMsg, control func(network, address string, c syscall.RawConn) error) (*SCTPListener, error) {
+func listenSCTPExtConfig(network string, laddr *SCTPAddr, options InitMsg, control func(network, address string, c syscall.RawConn) error, notificationHandler NotificationHandler) (*SCTPListener, error) {
 	af, ipv6only := favoriteAddrFamily(network, laddr, nil, "listen")
 	sock, err := syscall.Socket(
 		af,
@@ -232,14 +232,16 @@ func listenSCTPExtConfig(network string, laddr *SCTPAddr, options InitMsg, contr
 		return nil, err
 	}
 	return &SCTPListener{
-		fd: sock,
-	}, nil
+			fd:                  sock,
+			notificationHandler: notificationHandler,
+		},
+		nil
 }
 
 // AcceptSCTP waits for and returns the next SCTP connection to the listener.
 func (ln *SCTPListener) AcceptSCTP() (*SCTPConn, error) {
 	fd, _, err := syscall.Accept4(ln.fd, 0)
-	return NewSCTPConn(fd, nil), err
+	return NewSCTPConn(fd, ln.notificationHandler), err
 }
 
 // Accept waits for and returns the next connection connection to the listener.
@@ -259,11 +261,11 @@ func DialSCTP(net string, laddr, raddr *SCTPAddr) (*SCTPConn, error) {
 
 // DialSCTPExt - same as DialSCTP but with given SCTP options
 func DialSCTPExt(network string, laddr, raddr *SCTPAddr, options InitMsg) (*SCTPConn, error) {
-	return dialSCTPExtConfig(network, laddr, raddr, options, nil)
+	return dialSCTPExtConfig(network, laddr, raddr, options, nil, nil)
 }
 
 // dialSCTPExtConfig - same as DialSCTP but with given SCTP options and socket configuration
-func dialSCTPExtConfig(network string, laddr, raddr *SCTPAddr, options InitMsg, control func(network, address string, c syscall.RawConn) error) (*SCTPConn, error) {
+func dialSCTPExtConfig(network string, laddr, raddr *SCTPAddr, options InitMsg, control func(network, address string, c syscall.RawConn) error, notificationHandler NotificationHandler) (*SCTPConn, error) {
 	af, ipv6only := favoriteAddrFamily(network, laddr, raddr, "dial")
 	sock, err := syscall.Socket(
 		af,
@@ -315,5 +317,5 @@ func dialSCTPExtConfig(network string, laddr, raddr *SCTPAddr, options InitMsg,
 	if err != nil {
 		return nil, err
 	}
-	return NewSCTPConn(sock, nil), nil
+	return NewSCTPConn(sock, notificationHandler), nil
 }

sctp_linux_test.go

@@ -19,18 +19,56 @@
 package sctp
 
 import (
+	"errors"
 	"net"
 	"strings"
 	"syscall"
 	"testing"
 )
 
+func TestNotificationHandlerAssignmentOnDialing(t *testing.T) {
+	network := "sctp"
+	addr := &SCTPAddr{IPAddrs: []net.IPAddr{{IP: net.IPv4(127, 0, 0, 1)}}, Port: 54321}
+	testErr := errors.New("test error")
+	notificationHandler := func([]byte) error { return testErr }
+
+	listener, err := ListenSCTP(network, addr)
+	if err != nil {
+		t.Fatal(err)
+	}
+	conn, err := dialSCTPExtConfig(network, nil, addr, InitMsg{}, nil, notificationHandler)
+	if err != nil {
+		t.Fatalf("failed to establish connection due to: %v", err)
+	}
+	if conn == nil || conn.notificationHandler(nil) != testErr {
+		t.Fatalf("notification handler has not been assigned")
+	}
+	listener.Close()
+	conn.Close()
+}
+
+func TestNotificationHandlerAssignmentOnListening(t *testing.T) {
+	network := "sctp"
+	addr := &SCTPAddr{IPAddrs: []net.IPAddr{{IP: net.IPv4(127, 0, 0, 1)}}, Port: 54321}
+	testErr := errors.New("test error")
+	notificationHandler := func([]byte) error { return testErr }
+
+	listener, err := listenSCTPExtConfig(network, addr, InitMsg{}, nil, notificationHandler)
+	if err != nil {
+		t.Fatalf("failed to start listening due to: %v", err)
+	}
+	if listener == nil || listener.notificationHandler(nil) != testErr {
+		t.Fatalf("notification handler has not been assigned")
+	}
+	listener.Close()
+}
+
 func TestDialUseControlFuncWithoutLocalAddress(t *testing.T) {
 	network := "sctp"
 	raddr := &SCTPAddr{IPAddrs: []net.IPAddr{net.IPAddr{IP: net.IPv4(127, 0, 0, 1)}}}
 	initMsg := InitMsg{}
 	customControlFunc := validationControlFunc(t, network)
-	conn, err := dialSCTPExtConfig(network, nil, raddr, initMsg, customControlFunc)
+	conn, err := dialSCTPExtConfig(network, nil, raddr, initMsg, customControlFunc, nil)
 	if err != nil && !strings.Contains(err.Error(), "connection refused") {
 		t.Fatalf("failed to dial connection due to: %v", err)
 	}
@@ -41,7 +79,7 @@ func TestListenUseControlFuncWithoutLocalAddress(t *testing.T) {
 	network := "sctp"
 	initMsg := InitMsg{}
 	customControlFunc := validationControlFunc(t, network)
-	listener, err := listenSCTPExtConfig(network, nil, initMsg, customControlFunc)
+	listener, err := listenSCTPExtConfig(network, nil, initMsg, customControlFunc, nil)
 	if err != nil {
 		t.Fatalf("failed to start listener: %v", err)
 	}