l2tp: handle WEN and SLI messages by sessions

WEN and SLI messages carry session specific data and should be handled
by the session rather than by the tunnel. Session's state can now be
checked before accepting these message types.

Signed-off-by: Guillaume Nault <g.nault@alphalink.fr>

1 files changed, 26 insertions, 20 deletions

diff --git a/accel-pppd/ctrl/l2tp/l2tp.c b/accel-pppd/ctrl/l2tp/l2tp.c
index ae1e8045..a63b0a02 100644
--- a/accel-pppd/ctrl/l2tp/l2tp.c
+++ b/accel-pppd/ctrl/l2tp/l2tp.c
@@ -3399,38 +3399,42 @@ static int l2tp_recv_CDN(struct l2tp_sess_t *sess,
 	return 0;
 }
 
-static int l2tp_recv_WEN(struct l2tp_conn_t *conn,
+static int l2tp_recv_WEN(struct l2tp_sess_t *sess,
 			 const struct l2tp_packet_t *pack)
 {
-	if (!conn->lns_mode) {
-		log_tunnel(log_warn, conn, "discarding unexpected WEN\n");
+	if (sess->state1 != STATE_ESTB || !sess->paren_conn->lns_mode) {
+		log_session(log_warn, sess, "discarding unexpected WEN\n");
+
 		return 0;
 	}
 
-	log_tunnel(log_info2, conn, "handling WEN\n");
+	log_session(log_info2, sess, "handling WEN\n");
+
+	if (l2tp_send_ZLB(sess->paren_conn) < 0) {
+		log_session(log_error, sess, "impossible to handle WEN:"
+			    " sending ZLB failed\n");
 
-	if (l2tp_send_ZLB(conn) < 0) {
-		log_tunnel(log_error, conn, "impossible to handle WEN:"
-			   " sending ZLB failed\n");
 		return -1;
 	}
 
 	return 0;
 }
 
-static int l2tp_recv_SLI(struct l2tp_conn_t *conn,
+static int l2tp_recv_SLI(struct l2tp_sess_t *sess,
 			 const struct l2tp_packet_t *pack)
 {
-	if (conn->lns_mode) {
-		log_tunnel(log_warn, conn, "discarding unexpected SLI\n");
+	if (sess->state1 != STATE_ESTB || sess->paren_conn->lns_mode) {
+		log_session(log_warn, sess, "discarding unexpected SLI\n");
+
 		return 0;
 	}
 
-	log_tunnel(log_info2, conn, "handling SLI\n");
+	log_session(log_info2, sess, "handling SLI\n");
+
+	if (l2tp_send_ZLB(sess->paren_conn) < 0) {
+		log_session(log_error, sess, "impossible to handle SLI:"
+			    " sending ZLB failed\n");
 
-	if (l2tp_send_ZLB(conn) < 0) {
-		log_tunnel(log_error, conn, "impossible to handle SLI:"
-			   " sending ZLB failed\n");
 		return -1;
 	}
 
@@ -3529,6 +3533,12 @@ static void l2tp_session_recv(struct l2tp_sess_t *sess,
 	case Message_Type_Call_Disconnect_Notify:
 		l2tp_recv_CDN(sess, pack);
 		break;
+	case Message_Type_WAN_Error_Notify:
+		l2tp_recv_WEN(sess, pack);
+		break;
+	case Message_Type_Set_Link_Info:
+		l2tp_recv_SLI(sess, pack);
+		break;
 	default:
 		if (msg_type->M) {
 			log_session(log_error, sess,
@@ -3703,6 +3713,8 @@ static int l2tp_conn_read(struct triton_md_handler_t *h)
 			case Message_Type_Outgoing_Call_Reply:
 			case Message_Type_Outgoing_Call_Connected:
 			case Message_Type_Call_Disconnect_Notify:
+			case Message_Type_WAN_Error_Notify:
+			case Message_Type_Set_Link_Info:
 				sess = l2tp_tunnel_get_session(conn, ntohs(pack->hdr.sid));
 				if (sess == NULL) {
 					log_tunnel(log_warn, conn,
@@ -3714,12 +3726,6 @@ static int l2tp_conn_read(struct triton_md_handler_t *h)
 				}
 				l2tp_session_recv(sess, pack);
 				break;
-			case Message_Type_WAN_Error_Notify:
-				l2tp_recv_WEN(conn, pack);
-				break;
-			case Message_Type_Set_Link_Info:
-				l2tp_recv_SLI(conn, pack);
-				break;
 			case Message_Type_Start_Ctrl_Conn_Request:
 				log_tunnel(log_warn, conn,
 					   "discarding unexpected SCCRQ\n");