1 files changed, 140 insertions, 0 deletions
diff --git a/ip/iplink_gtp.c b/ip/iplink_gtp.c
new file mode 100644
index 0000000..086946b
--- /dev/null
+++ b/ip/iplink_gtp.c
@@ -0,0 +1,140 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#include <stdio.h>
+
+#include "rt_names.h"
+#include "utils.h"
+#include "ip_common.h"
+
+#define GTP_ATTRSET(attrs, type) (((attrs) & (1L << (type))) != 0)
+
+static void print_explain(FILE *f)
+{
+	fprintf(f,
+		"Usage: ... gtp role ROLE\n"
+		"		[ hsize HSIZE ]\n"
+		"		[ restart_count RESTART_COUNT ]\n"
+		"\n"
+		"Where:	ROLE		:= { sgsn | ggsn }\n"
+		"	HSIZE		:= 1-131071\n"
+		"	RESTART_COUNT	:= 0-255\n"
+	);
+}
+
+static void check_duparg(__u32 *attrs, int type, const char *key,
+			 const char *argv)
+{
+	if (!GTP_ATTRSET(*attrs, type)) {
+		*attrs |= (1L << type);
+		return;
+	}
+	duparg2(key, argv);
+}
+
+static int gtp_parse_opt(struct link_util *lu, int argc, char **argv,
+			 struct nlmsghdr *n)
+{
+	__u32 attrs = 0;
+
+	/* When creating GTP device through ip link,
+	 * this flag has to be set.
+	 */
+	addattr8(n, 1024, IFLA_GTP_CREATE_SOCKETS, true);
+
+	while (argc > 0) {
+		if (!strcmp(*argv, "role")) {
+			NEXT_ARG();
+			check_duparg(&attrs, IFLA_GTP_ROLE, "role", *argv);
+			if (!strcmp(*argv, "sgsn"))
+				addattr32(n, 1024, IFLA_GTP_ROLE, GTP_ROLE_SGSN);
+			else if (!strcmp(*argv, "ggsn"))
+				addattr32(n, 1024, IFLA_GTP_ROLE, GTP_ROLE_GGSN);
+			else
+				invarg("invalid role, use sgsn or ggsn", *argv);
+		} else if (!strcmp(*argv, "hsize")) {
+			__u32 hsize;
+
+			NEXT_ARG();
+			check_duparg(&attrs, IFLA_GTP_PDP_HASHSIZE, "hsize", *argv);
+
+			if (get_u32(&hsize, *argv, 0))
+				invarg("invalid PDP hash size", *argv);
+			if (hsize >= 1u << 17)
+				invarg("PDP hash size too big", *argv);
+			addattr32(n, 1024, IFLA_GTP_PDP_HASHSIZE, hsize);
+		} else if (!strcmp(*argv, "restart_count")) {
+			__u8 restart_count;
+
+			NEXT_ARG();
+			check_duparg(&attrs, IFLA_GTP_RESTART_COUNT, "restart_count", *argv);
+
+			if (get_u8(&restart_count, *argv, 10))
+				invarg("invalid restart_count", *argv);
+			addattr8(n, 1024, IFLA_GTP_RESTART_COUNT, restart_count);
+		} else if (!strcmp(*argv, "help")) {
+			print_explain(stderr);
+			return -1;
+		}
+		argc--, argv++;
+	}
+
+	if (!GTP_ATTRSET(attrs, IFLA_GTP_ROLE)) {
+		fprintf(stderr, "gtp: role of the gtp device was not specified\n");
+		return -1;
+	}
+
+	if (!GTP_ATTRSET(attrs, IFLA_GTP_PDP_HASHSIZE))
+		addattr32(n, 1024, IFLA_GTP_PDP_HASHSIZE, 1024);
+
+	return 0;
+}
+
+static const char *gtp_role_to_string(__u32 role)
+{
+	switch (role) {
+	case GTP_ROLE_GGSN:
+		return "ggsn";
+	case GTP_ROLE_SGSN:
+		return "sgsn";
+	default:
+		return "unknown";
+	}
+}
+
+static void gtp_print_opt(struct link_util *lu, FILE *f, struct rtattr *tb[])
+{
+
+	if (tb[IFLA_GTP_ROLE]) {
+		__u32 role = rta_getattr_u32(tb[IFLA_GTP_ROLE]);
+
+		print_string(PRINT_ANY, "role", "role %s ",
+			     gtp_role_to_string(role));
+	}
+
+	if (tb[IFLA_GTP_PDP_HASHSIZE]) {
+		__u32 hsize = rta_getattr_u32(tb[IFLA_GTP_PDP_HASHSIZE]);
+
+		print_uint(PRINT_ANY, "hsize", "hsize %u ", hsize);
+	}
+
+	if (tb[IFLA_GTP_RESTART_COUNT]) {
+		__u8 restart_count = rta_getattr_u8(tb[IFLA_GTP_RESTART_COUNT]);
+
+		print_uint(PRINT_ANY, "restart_count",
+			   "restart_count %u ", restart_count);
+	}
+}
+
+static void gtp_print_help(struct link_util *lu, int argc, char **argv,
+			   FILE *f)
+{
+	print_explain(f);
+}
+
+struct link_util gtp_link_util = {
+	.id		= "gtp",
+	.maxattr	= IFLA_GTP_MAX,
+	.parse_opt	= gtp_parse_opt,
+	.print_opt	= gtp_print_opt,
+	.print_help	= gtp_print_help,
+};