diff --git a/Makefile b/Makefile
index c4e027f..890570f 100644
--- a/Makefile
+++ b/Makefile
@@ -7,8 +7,7 @@ default:
 	$(MAKE) -C $(KDIR) SUBDIRS=$(PWD) modules
 	$(CC) -lmnl gtp-link-add.c -o gtp-link-add
 	$(CC) -lmnl gtp-cfg-add.c genl.c -o gtp-cfg-add
-	$(CC) -lmnl gtp-tunnel-add.c genl.c gtpnl.c -o gtp-tunnel-add
-	$(CC) -lmnl -g gtp-tunnel-get.c genl.o -o gtp-tunnel-get
+	$(CC) -lmnl gtp-tunnel.c genl.c gtpnl.c -o gtp-tunnel
 clean:
 	rm -rf *.o *.mod.* modules.order Module.symvers *.ko .tmp_versions .*.cmd
 	rm -f genl-family-get gtp-link-add gtp-tunnel-add
diff --git a/gtp-tunnel-add.c b/gtp-tunnel-add.c
deleted file mode 100644
index 8c98c5e..0000000
--- a/gtp-tunnel-add.c
+++ /dev/null
@@ -1,68 +0,0 @@
-#include <stdio.h>
-#include <stdlib.h>
-#include <unistd.h>
-#include <time.h>
-#include <arpa/inet.h>
-#include <sys/socket.h>
-#include <netinet/in.h>
-
-#include <libmnl/libmnl.h>
-#include <linux/genetlink.h>
-
-#include "gtp.h"
-#include "genl.h"
-
-static uint32_t seq;
-
-int main(int argc, char *argv[])
-{
-	struct mnl_socket *nl;
-	char buf[MNL_SOCKET_BUFFER_SIZE];
-	struct nlmsghdr *nlh;
-	struct genlmsghdr *genl;
-	unsigned int portid;
-	uint32_t gtp_ifidx;
-	int32_t genl_id;
-	struct in_addr ms, sgsn;
-
-	if (argc != 6) {
-		printf("%s <gtp device> <version> <tid> <ms-addr> <sgsn-addr>\n",
-			argv[0]);
-		exit(EXIT_FAILURE);
-	}
-	gtp_ifidx = if_nametoindex(argv[1]);
-
-	nl = genl_socket_open();
-	if (nl == NULL) {
-		perror("mnl_socket_open");
-		exit(EXIT_FAILURE);
-	}
-
-	genl_id = genl_lookup_family(nl, "gtp");
-	if (genl_id < 0) {
-		printf("not found gtp genl family\n");
-		exit(EXIT_FAILURE);
-	}
-
-	if (inet_aton(argv[4], &ms) < 0) {
-		perror("bad address for ms");
-		exit(EXIT_FAILURE);
-	}
-
-	if (inet_aton(argv[5], &sgsn) < 0) {
-		perror("bad address for sgsn");
-		exit(EXIT_FAILURE);
-	}
-
-	nlh = genl_nlmsg_build_hdr(buf, genl_id, NLM_F_EXCL | NLM_F_ACK, ++seq,
-				   GTP_CMD_TUNNEL_NEW);
-	gtp_build_payload(nlh, atoi(argv[3]), gtp_ifidx, sgsn.s_addr,
-			  ms.s_addr, atoi(argv[2]));
-
-	if (genl_socket_talk(nl, nlh, seq, NULL, NULL) < 0)
-		perror("genl_socket_talk");
-
-	mnl_socket_close(nl);
-
-	return 0;
-}
diff --git a/gtp-tunnel-get.c b/gtp-tunnel-get.c
deleted file mode 100644
index 274250e..0000000
--- a/gtp-tunnel-get.c
+++ /dev/null
@@ -1,115 +0,0 @@
-#include <stdio.h>
-#include <stdlib.h>
-#include <unistd.h>
-#include <time.h>
-#include <sys/socket.h>
-#include <netinet/in.h>
-#include <arpa/inet.h>
-
-#include <libmnl/libmnl.h>
-#include <linux/genetlink.h>
-
-#include "gtp.h"
-#include "genl.h"
-
-struct gtp_pdp {
-	uint32_t	version;
-	uint64_t	tid;
-	struct in_addr	sgsn_addr;
-	struct in_addr	ms_addr;
-};
-
-static uint32_t seq = 10;
-
-static int genl_gtp_validate_cb(const struct nlattr *attr, void *data)
-{
-	const struct nlattr **tb = data;
-	int type = mnl_attr_get_type(attr);
-
-	if (mnl_attr_type_valid(attr, CTRL_ATTR_MAX) < 0)
-		return MNL_CB_OK;
-
-	switch(type) {
-	case GTPA_TID:
-		if (mnl_attr_validate(attr, MNL_TYPE_U64) < 0) {
-			perror("mnl_attr_validate");
-			return MNL_CB_ERROR;
-		}
-		break;
-	case GTPA_SGSN_ADDRESS:
-	case GTPA_MS_ADDRESS:
-	case GTPA_VERSION:
-		if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0) {
-			perror("mnl_attr_validate");
-			return MNL_CB_ERROR;
-		}
-		break;
-	default:
-		break;
-	}
-	tb[type] = attr;
-	return MNL_CB_OK;
-}
-
-static int genl_gtp_attr_cb(const struct nlmsghdr *nlh, void *data)
-{
-	struct nlattr *tb[GTPA_MAX + 1] = {};
-	struct gtp_pdp *pdp = data;
-	struct genlmsghdr *genl;
-
-	mnl_attr_parse(nlh, sizeof(*genl), genl_gtp_validate_cb, tb);
-	if (tb[GTPA_TID])
-		pdp->tid = mnl_attr_get_u64(tb[GTPA_TID]);
-	if (tb[GTPA_SGSN_ADDRESS]) {
-		pdp->sgsn_addr.s_addr =
-			mnl_attr_get_u32(tb[GTPA_SGSN_ADDRESS]);
-	}
-	if (tb[GTPA_MS_ADDRESS]) {
-		pdp->ms_addr.s_addr = mnl_attr_get_u32(tb[GTPA_MS_ADDRESS]);
-	}
-	if (tb[GTPA_VERSION]) {
-		pdp->version = mnl_attr_get_u32(tb[GTPA_VERSION]);
-	}
-
-	printf("version %u ", pdp->version);
-	printf("tid %llu ms_addr %s ", pdp->tid, inet_ntoa(pdp->sgsn_addr));
-	printf("sgsn_addr %s\n", inet_ntoa(pdp->ms_addr));
-
-	return MNL_CB_OK;
-}
-
-int main(int argc, char *argv[])
-{
-	struct mnl_socket *nl;
-	char buf[MNL_SOCKET_BUFFER_SIZE];
-	struct nlmsghdr *nlh;
-	struct genlmsghdr *genl;
-	unsigned int portid;
-	int32_t genl_id;
-	struct gtp_pdp pdp;
-	int i;
-
-	nl = genl_socket_open();
-	if (nl == NULL) {
-		perror("mnl_socket_open");
-		exit(EXIT_FAILURE);
-	}
-
-	genl_id = genl_lookup_family(nl, "gtp");
-	if (genl_id < 0) {
-		printf("not found gtp genl family\n");
-		exit(EXIT_FAILURE);
-	}
-
-	nlh = genl_nlmsg_build_hdr(buf, genl_id, NLM_F_DUMP, 0,
-				   GTP_CMD_TUNNEL_GET);
-
-	if (genl_socket_talk(nl, nlh, seq, genl_gtp_attr_cb, &pdp) < 0) {
-		perror("genl_socket_talk");
-		return 0;
-	}
-
-	mnl_socket_close(nl);
-
-	return 0;
-}
diff --git a/gtp-tunnel.c b/gtp-tunnel.c
new file mode 100644
index 0000000..de1c1b0
--- /dev/null
+++ b/gtp-tunnel.c
@@ -0,0 +1,200 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <time.h>
+#include <arpa/inet.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+
+#include <libmnl/libmnl.h>
+#include <linux/genetlink.h>
+
+#include "gtp.h"
+#include "genl.h"
+
+static int
+add_tunnel(int argc, char *argv[], int genl_id, struct mnl_socket *nl)
+{
+	uint32_t gtp_ifidx;
+	struct in_addr ms, sgsn;
+	struct nlmsghdr *nlh;
+	char buf[MNL_SOCKET_BUFFER_SIZE];
+	uint32_t seq = time(NULL);
+
+	if (argc != 7) {
+		printf("%s add <gtp device> <version> <tid> <ms-addr> <sgsn-addr>\n",
+			argv[0]);
+		return EXIT_FAILURE;
+	}
+	gtp_ifidx = if_nametoindex(argv[2]);
+
+	if (inet_aton(argv[5], &ms) < 0) {
+		perror("bad address for ms");
+		exit(EXIT_FAILURE);
+	}
+
+	if (inet_aton(argv[6], &sgsn) < 0) {
+		perror("bad address for sgsn");
+		exit(EXIT_FAILURE);
+	}
+
+	nlh = genl_nlmsg_build_hdr(buf, genl_id, NLM_F_EXCL | NLM_F_ACK, ++seq,
+				   GTP_CMD_TUNNEL_NEW);
+	gtp_build_payload(nlh, atoi(argv[4]), gtp_ifidx, sgsn.s_addr,
+			  ms.s_addr, atoi(argv[3]));
+
+	if (genl_socket_talk(nl, nlh, seq, NULL, NULL) < 0)
+		perror("genl_socket_talk");
+
+	return 0;
+}
+
+static int
+del_tunnel(int argc, char *argv[], int genl_id, struct mnl_socket *nl)
+{
+	uint32_t gtp_ifidx;
+	char buf[MNL_SOCKET_BUFFER_SIZE];
+	struct nlmsghdr *nlh;
+	uint32_t seq = time(NULL);
+
+	if (argc != 5) {
+		printf("%s add <gtp device> <version> <tid>\n",
+			argv[0]);
+		return EXIT_FAILURE;
+	}
+
+	gtp_ifidx = if_nametoindex(argv[2]);
+
+	nlh = genl_nlmsg_build_hdr(buf, genl_id, NLM_F_EXCL | NLM_F_ACK, ++seq,
+				   GTP_CMD_TUNNEL_NEW);
+	gtp_build_payload(nlh, atoi(argv[4]), gtp_ifidx, 0, 0, atoi(argv[3]));
+
+	if (genl_socket_talk(nl, nlh, seq, NULL, NULL) < 0)
+		perror("genl_socket_talk");
+
+	return 0;
+}
+
+struct gtp_pdp {
+	uint32_t	version;
+	uint64_t	tid;
+	struct in_addr	sgsn_addr;
+	struct in_addr	ms_addr;
+};
+
+static int genl_gtp_validate_cb(const struct nlattr *attr, void *data)
+{
+	const struct nlattr **tb = data;
+	int type = mnl_attr_get_type(attr);
+
+	if (mnl_attr_type_valid(attr, CTRL_ATTR_MAX) < 0)
+		return MNL_CB_OK;
+
+	switch(type) {
+	case GTPA_TID:
+		if (mnl_attr_validate(attr, MNL_TYPE_U64) < 0) {
+			perror("mnl_attr_validate");
+			return MNL_CB_ERROR;
+		}
+		break;
+	case GTPA_SGSN_ADDRESS:
+	case GTPA_MS_ADDRESS:
+	case GTPA_VERSION:
+		if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0) {
+			perror("mnl_attr_validate");
+			return MNL_CB_ERROR;
+		}
+		break;
+	default:
+		break;
+	}
+	tb[type] = attr;
+	return MNL_CB_OK;
+}
+
+static int genl_gtp_attr_cb(const struct nlmsghdr *nlh, void *data)
+{
+	struct nlattr *tb[GTPA_MAX + 1] = {};
+	struct gtp_pdp pdp;
+	struct genlmsghdr *genl;
+
+	mnl_attr_parse(nlh, sizeof(*genl), genl_gtp_validate_cb, tb);
+	if (tb[GTPA_TID])
+		pdp.tid = mnl_attr_get_u64(tb[GTPA_TID]);
+	if (tb[GTPA_SGSN_ADDRESS]) {
+		pdp.sgsn_addr.s_addr =
+			mnl_attr_get_u32(tb[GTPA_SGSN_ADDRESS]);
+	}
+	if (tb[GTPA_MS_ADDRESS]) {
+		pdp.ms_addr.s_addr = mnl_attr_get_u32(tb[GTPA_MS_ADDRESS]);
+	}
+	if (tb[GTPA_VERSION]) {
+		pdp.version = mnl_attr_get_u32(tb[GTPA_VERSION]);
+	}
+
+	printf("version %u ", pdp.version);
+	printf("tid %llu ms_addr %s ", pdp.tid, inet_ntoa(pdp.sgsn_addr));
+	printf("sgsn_addr %s\n", inet_ntoa(pdp.ms_addr));
+
+	return MNL_CB_OK;
+}
+
+static int
+list_tunnel(int argc, char *argv[], int genl_id, struct mnl_socket *nl)
+{
+	char buf[MNL_SOCKET_BUFFER_SIZE];
+	struct nlmsghdr *nlh;
+	uint32_t seq = time(NULL);
+
+	nlh = genl_nlmsg_build_hdr(buf, genl_id, NLM_F_DUMP, 0,
+				   GTP_CMD_TUNNEL_GET);
+
+	if (genl_socket_talk(nl, nlh, seq, genl_gtp_attr_cb, NULL) < 0) {
+		perror("genl_socket_talk");
+		return 0;
+	}
+
+	return 0;
+}
+
+int main(int argc, char *argv[])
+{
+	struct mnl_socket *nl;
+	char buf[MNL_SOCKET_BUFFER_SIZE];
+	unsigned int portid;
+	int32_t genl_id;
+	int ret;
+
+	if (argc < 2) {
+		printf("%s <add|delete|list> [<options,...>]\n", argv[0]);
+		exit(EXIT_FAILURE);
+	}
+
+	nl = genl_socket_open();
+	if (nl == NULL) {
+		perror("mnl_socket_open");
+		exit(EXIT_FAILURE);
+	}
+
+	genl_id = genl_lookup_family(nl, "gtp");
+	if (genl_id < 0) {
+		printf("not found gtp genl family\n");
+		exit(EXIT_FAILURE);
+	}
+
+	if (strncmp(argv[1], "add", strlen(argv[1])) == 0)
+		ret = add_tunnel(argc, argv, genl_id, nl);
+	else if (strncmp(argv[1], "delete", strlen(argv[1])) == 0)
+		ret = del_tunnel(argc, argv, genl_id, nl);
+	else if (strncmp(argv[1], "list", strlen(argv[1])) == 0)
+		ret = list_tunnel(argc, argv, genl_id, nl);
+	else {
+		printf("Unknown command `%s'\n", argv[1]);
+		exit(EXIT_FAILURE);
+	}
+
+	mnl_socket_close(nl);
+
+	return ret;
+}