2 files changed, 174 insertions, 0 deletions

diff --git a/tests/sys/netlink/Makefile b/tests/sys/netlink/Makefile
index c07ef8663867..43b9db80ee63 100644
--- a/tests/sys/netlink/Makefile
+++ b/tests/sys/netlink/Makefile
@@ -5,6 +5,7 @@ TESTSDIR=       ${TESTSBASE}/sys/netlink
 
 ATF_TESTS_C+=	netlink_socket
 ATF_TESTS_C+=	test_snl test_snl_generic
+ATF_TESTS_C+=	test_rtnl_gre
 ATF_TESTS_PYTEST +=	test_nl_core.py
 ATF_TESTS_PYTEST +=	test_rtnl_iface.py
 ATF_TESTS_PYTEST +=	test_rtnl_ifaddr.py
diff --git a/tests/sys/netlink/test_rtnl_gre.c b/tests/sys/netlink/test_rtnl_gre.c
new file mode 100644
index 000000000000..12ecc8d14230
--- /dev/null
+++ b/tests/sys/netlink/test_rtnl_gre.c
@@ -0,0 +1,173 @@
+/*
+ * Copyright (c) 2026 Pouria Mousavizadeh Tehrani <pouria@FreeBSD.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <sys/param.h>
+#include <sys/module.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <net/if_gre.h>
+
+#include <netlink/netlink.h>
+#include <netlink/netlink_route.h>
+#include "netlink/netlink_snl.h"
+#include <netlink/netlink_snl_route.h>
+#include <netlink/netlink_snl_route_compat.h>
+#include <netlink/netlink_snl_route_parsers.h>
+
+#include <atf-c.h>
+
+struct nl_parsed_gre {
+	struct sockaddr		*ifla_local;
+	struct sockaddr		*ifla_remote;
+	uint32_t		ifla_flags;
+	uint32_t		ifla_okey;
+	uint32_t		ifla_encap_type;
+	uint16_t		ifla_encap_sport;
+};
+
+struct nla_gre_info {
+	const char		*kind;
+	struct nl_parsed_gre	data;
+};
+
+struct nla_gre_link {
+	uint32_t		ifi_index;
+	struct nla_gre_info	linkinfo;
+};
+
+#define _OUT(_field)	offsetof(struct nl_parsed_gre, _field)
+static const struct snl_attr_parser nla_p_gre[] = {
+	{ .type = IFLA_GRE_LOCAL, .off = _OUT(ifla_local), .cb = snl_attr_get_ip },
+	{ .type = IFLA_GRE_REMOTE, .off = _OUT(ifla_remote), .cb = snl_attr_get_ip },
+	{ .type = IFLA_GRE_FLAGS, .off = _OUT(ifla_flags), .cb = snl_attr_get_uint32 },
+	{ .type = IFLA_GRE_OKEY, .off = _OUT(ifla_okey), .cb = snl_attr_get_uint32 },
+	{ .type = IFLA_GRE_ENCAP_TYPE, .off = _OUT(ifla_encap_type), .cb = snl_attr_get_uint32 },
+	{ .type = IFLA_GRE_ENCAP_SPORT, .off = _OUT(ifla_encap_sport), .cb = snl_attr_get_uint16 },
+};
+#undef _OUT
+SNL_DECLARE_ATTR_PARSER(gre_linkinfo_data_parser, nla_p_gre);
+
+#define _OUT(_field)	offsetof(struct nla_gre_info, _field)
+static const struct snl_attr_parser ap_gre_linkinfo[] = {
+	{ .type = IFLA_INFO_KIND, .off = _OUT(kind), .cb = snl_attr_get_string },
+	{ .type = IFLA_INFO_DATA, .off = _OUT(data),
+		.arg = &gre_linkinfo_data_parser, .cb = snl_attr_get_nested },
+};
+#undef _OUT
+SNL_DECLARE_ATTR_PARSER(gre_linkinfo_parser, ap_gre_linkinfo);
+
+#define _IN(_field)	offsetof(struct ifinfomsg, _field)
+#define _OUT(_field)	offsetof(struct nla_gre_link, _field)
+static const struct snl_attr_parser ap_gre_link[] = {
+	{ .type = IFLA_LINKINFO, .off = _OUT(linkinfo),
+		.arg = &gre_linkinfo_parser, .cb = snl_attr_get_nested },
+};
+
+static const struct snl_field_parser fp_gre_link[] = {
+	{ .off_in = _IN(ifi_index), .off_out = _OUT(ifi_index), .cb = snl_field_get_uint32 },
+};
+#undef _IN
+#undef _OUT
+SNL_DECLARE_PARSER(gre_parser, struct ifinfomsg, fp_gre_link, ap_gre_link);
+
+ATF_TC(test_rtnl_gre);
+ATF_TC_HEAD(test_rtnl_gre, tc)
+{
+	atf_tc_set_md_var(tc, "descr", "test gre interface using netlink");
+	atf_tc_set_md_var(tc, "require.user", "root");
+}
+
+ATF_TC_BODY(test_rtnl_gre, tc)
+{
+	struct snl_state ss;
+	struct snl_writer nw;
+	struct nlmsghdr *hdr, *rx_hdr;
+	struct sockaddr_in src, dst;
+	struct nla_gre_link lattrs = {};
+	struct nl_parsed_gre attrs = {};
+	struct snl_errmsg_data e = {};
+	struct ifinfomsg *ifmsg;
+	int off, off2;
+
+	ATF_REQUIRE_MSG(snl_init(&ss, NETLINK_ROUTE), "snl_init() failed");
+
+	/* Create gre interface */
+	snl_init_writer(&ss, &nw);
+	ATF_REQUIRE((hdr = snl_create_msg_request(&nw, RTM_NEWLINK)) != NULL);
+	hdr->nlmsg_flags |= (NLM_F_CREATE | NLM_F_EXCL | NLM_F_REQUEST | NLM_F_ACK);
+	snl_reserve_msg_object(&nw, struct ifinfomsg);
+
+	/* Create parameters */
+	snl_add_msg_attr_string(&nw, IFLA_IFNAME, "gre10");
+	off = snl_add_msg_attr_nested(&nw, IFLA_LINKINFO);
+        snl_add_msg_attr_string(&nw, IFLA_INFO_KIND, "gre");
+	off2 = snl_add_msg_attr_nested(&nw, IFLA_INFO_DATA);
+
+	src.sin_family = AF_INET;
+	dst.sin_family = AF_INET;
+	inet_pton(src.sin_family, "127.0.0.1", &src.sin_addr);
+	inet_pton(dst.sin_family, "127.0.0.2", &dst.sin_addr);
+	snl_add_msg_attr_ip(&nw, IFLA_GRE_LOCAL, (struct sockaddr *)&src);
+	snl_add_msg_attr_ip(&nw, IFLA_GRE_REMOTE, (struct sockaddr *)&dst);
+	snl_add_msg_attr_u32(&nw, IFLA_GRE_FLAGS, (GRE_ENABLE_SEQ | GRE_ENABLE_CSUM));
+	snl_add_msg_attr_u32(&nw, IFLA_GRE_OKEY, 123456);
+	snl_add_msg_attr_u32(&nw, IFLA_GRE_ENCAP_TYPE, IFLA_TUNNEL_GRE_UDP);
+	snl_add_msg_attr_u16(&nw, IFLA_GRE_ENCAP_SPORT, 50000);
+
+	snl_end_attr_nested(&nw, off2);
+	snl_end_attr_nested(&nw, off);
+
+	ATF_REQUIRE((hdr = snl_finalize_msg(&nw)) != NULL);
+	ATF_REQUIRE(snl_send_message(&ss, hdr));
+	ATF_REQUIRE((rx_hdr = snl_read_reply(&ss, hdr->nlmsg_seq)) != NULL);
+	ATF_REQUIRE(snl_parse_errmsg(&ss, rx_hdr, &e));
+	ATF_REQUIRE_INTEQ(e.error, 0);
+
+	/* Dump gre interface */
+	snl_init_writer(&ss, &nw);
+	ATF_REQUIRE((hdr = snl_create_msg_request(&nw, RTM_GETLINK)) != NULL);
+	hdr->nlmsg_flags |= NLM_F_DUMP;
+	snl_reserve_msg_object(&nw, struct ifinfomsg);
+	snl_add_msg_attr_string(&nw, IFLA_IFNAME, "gre10");
+	off = snl_add_msg_attr_nested(&nw, IFLA_LINKINFO);
+        snl_add_msg_attr_string(&nw, IFLA_INFO_KIND, "gre");
+	snl_end_attr_nested(&nw, off);
+
+	ATF_REQUIRE((hdr = snl_finalize_msg(&nw)) != NULL);
+	ATF_REQUIRE(snl_send_message(&ss, hdr));
+
+	/* Check parameters */
+	ATF_REQUIRE((rx_hdr = snl_read_reply(&ss, hdr->nlmsg_seq)) != NULL);
+	ATF_CHECK(snl_parse_nlmsg(&ss, rx_hdr, &gre_parser, &lattrs));
+	attrs = lattrs.linkinfo.data;
+	ATF_CHECK_STREQ(lattrs.linkinfo.kind, "gre");
+	ATF_CHECK_INTEQ(attrs.ifla_flags, (GRE_ENABLE_SEQ | GRE_ENABLE_CSUM | GRE_UDPENCAP));
+	ATF_CHECK_INTEQ(attrs.ifla_okey, 123456);
+	ATF_CHECK_INTEQ(attrs.ifla_encap_type, IFLA_TUNNEL_GRE_UDP);
+	ATF_CHECK_INTEQ(attrs.ifla_encap_sport, 50000);
+
+	/* Delete gre interface */
+	snl_init_writer(&ss, &nw);
+	ATF_REQUIRE((hdr = snl_create_msg_request(&nw, RTM_DELLINK)) != NULL);
+	hdr->nlmsg_flags |= (NLM_F_ACK | NLM_F_REQUEST);
+	ATF_REQUIRE((ifmsg = snl_reserve_msg_object(&nw, struct ifinfomsg)) != NULL);
+	ifmsg->ifi_index = lattrs.ifi_index;
+	ATF_REQUIRE((hdr = snl_finalize_msg(&nw)) != NULL);
+	ATF_REQUIRE(snl_send_message(&ss, hdr));
+	ATF_REQUIRE((rx_hdr = snl_read_reply(&ss, hdr->nlmsg_seq)) != NULL);
+	ATF_REQUIRE(snl_parse_errmsg(&ss, rx_hdr, &e));
+	ATF_REQUIRE_INTEQ(e.error, 0);
+}
+
+ATF_TP_ADD_TCS(tp)
+{
+	ATF_TP_ADD_TC(tp, test_rtnl_gre);
+
+	return (atf_no_error());
+}
+