[RFC nf-next v2 2/2] selftests/bpf: Add netfilter link prog update test

D. Wythe
2023-12-18T04:18:36Z

From: "D. Wythe" <alibuda@linux.alibaba.com>

Update prog for active links and verify whether
the prog has been successfully replaced.

Expected output:

./test_progs -t netfilter_link_update_prog
Summary: 1/0 PASSED, 0 SKIPPED, 0 FAILED

Signed-off-by: D. Wythe <alibuda@linux.alibaba.com>
---
.../bpf/prog_tests/netfilter_link_update_prog.c | 83 ++++++++++++++++++++++
.../bpf/progs/test_netfilter_link_update_prog.c | 24 +++++++
2 files changed, 107 insertions(+)
create mode 100644 tools/testing/selftests/bpf/prog_tests/netfilter_link_update_prog.c
create mode 100644 tools/testing/selftests/bpf/progs/test_netfilter_link_update_prog.c

diff --git a/tools/testing/selftests/bpf/prog_tests/netfilter_link_update_prog.c b/tools/testing/selftests/bpf/prog_tests/netfilter_link_update_prog.c
new file mode 100644
index 00000000..d23b544
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/netfilter_link_update_prog.c
@@ -0,0 +1,83 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include <test_progs.h>
+#include <linux/netfilter.h>
+#include <network_helpers.h>
+#include "test_netfilter_link_update_prog.skel.h"
+
+#define SERVER_ADDR "127.0.0.1"
+#define SERVER_PORT 12345
+
+static const char dummy_message[] = "A dummy message";
+
+static int send_dummy(int client_fd)
+{
+ struct sockaddr_storage saddr;
+ struct sockaddr *saddr_p;
+ socklen_t saddr_len;
+ int err;
+
+ saddr_p = (struct sockaddr *)&saddr;
+ err = make_sockaddr(AF_INET, SERVER_ADDR, SERVER_PORT, &saddr, &saddr_len);
+ if (!ASSERT_OK(err, "make_sockaddr"))
+ return -1;
+
+ err = sendto(client_fd, dummy_message, sizeof(dummy_message) - 1, 0, saddr_p, saddr_len);
+ if (!ASSERT_GE(err, 0, "sendto"))
+ return -1;
+
+ return 0;
+}
+
+void test_netfilter_link_update_prog(void)
+{
+ LIBBPF_OPTS(bpf_netfilter_opts, opts,
+ .pf = NFPROTO_IPV4,
+ .hooknum = NF_INET_LOCAL_OUT,
+ .priority = 100);
+ struct test_netfilter_link_update_prog *skel;
+ struct bpf_program *prog;
+ int server_fd, client_fd;
+ int err;
+
+ skel = test_netfilter_link_update_prog__open_and_load();
+ if (!ASSERT_OK_PTR(skel, "test_netfilter_link_update_prog__open_and_load"))
+ goto out;
+
+ prog = skel->progs.nf_link_prog;
+
+ if (!ASSERT_OK_PTR(prog, "load program"))
+ goto out;
+
+ skel->links.nf_link_prog = bpf_program__attach_netfilter(prog, &opts);
+ if (!ASSERT_OK_PTR(skel->links.nf_link_prog, "attach netfilter program"))
+ goto out;
+
+ server_fd = start_server(AF_INET, SOCK_DGRAM, SERVER_ADDR, SERVER_PORT, 0);
+ if (!ASSERT_GE(server_fd, 0, "start_server"))
+ goto out;
+
+ client_fd = connect_to_fd(server_fd, 0);
+ if (!ASSERT_GE(client_fd, 0, "connect_to_fd"))
+ goto out;
+
+ send_dummy(client_fd);
+
+ ASSERT_EQ(skel->bss->counter, 0, "counter should be zero");
+
+ err = bpf_link__update_program(skel->links.nf_link_prog, skel->progs.nf_link_prog_new);
+ if (!ASSERT_OK(err, "bpf_link__update_program"))
+ goto out;
+
+ send_dummy(client_fd);
+ ASSERT_GE(skel->bss->counter, 0, "counter should be greater than zero");
+out:
+ if (client_fd > 0)
+ close(client_fd);
+ if (server_fd > 0)
+ close(server_fd);
+
+ test_netfilter_link_update_prog__destroy(skel);
+}
+
+
diff --git a/tools/testing/selftests/bpf/progs/test_netfilter_link_update_prog.c b/tools/testing/selftests/bpf/progs/test_netfilter_link_update_prog.c
new file mode 100644
index 00000000..42ae332
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/test_netfilter_link_update_prog.c
@@ -0,0 +1,24 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include "vmlinux.h"
+#include <bpf/bpf_helpers.h>
+
+#define NF_ACCEPT 1
+
+SEC("netfilter")
+int nf_link_prog(struct bpf_nf_ctx *ctx)
+{
+ return NF_ACCEPT;
+}
+
+u64 counter = 0;
+
+SEC("netfilter")
+int nf_link_prog_new(struct bpf_nf_ctx *ctx)
+{
+ counter++;
+ return NF_ACCEPT;
+}
+
+char _license[] SEC("license") = "GPL";
+
--
1.8.3.1