selftests/bpf: netns_new() and netns_free() helpers.

netns_new()/netns_free() create/delete network namespaces. They support the
option '-m' of test_progs to start/stop traffic monitor for the network
namespace being created for matched tests.

Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com>
Link: https://lore.kernel.org/r/20240815053254.470944-4-thinker.li@gmail.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>

1 files changed, 46 insertions, 0 deletions

diff --git a/tools/testing/selftests/bpf/network_helpers.c b/tools/testing/selftests/bpf/network_helpers.c
index e0b0a69f066e..27784946b01b 100644
--- a/tools/testing/selftests/bpf/network_helpers.c
+++ b/tools/testing/selftests/bpf/network_helpers.c
@@ -446,6 +446,52 @@ char *ping_command(int family)
 	return "ping";
 }
 
+int remove_netns(const char *name)
+{
+	char *cmd;
+	int r;
+
+	r = asprintf(&cmd, "ip netns del %s >/dev/null 2>&1", name);
+	if (r < 0) {
+		log_err("Failed to malloc cmd");
+		return -1;
+	}
+
+	r = system(cmd);
+	free(cmd);
+	return r;
+}
+
+int make_netns(const char *name)
+{
+	char *cmd;
+	int r;
+
+	r = asprintf(&cmd, "ip netns add %s", name);
+	if (r < 0) {
+		log_err("Failed to malloc cmd");
+		return -1;
+	}
+
+	r = system(cmd);
+	free(cmd);
+
+	if (r)
+		return r;
+
+	r = asprintf(&cmd, "ip -n %s link set lo up", name);
+	if (r < 0) {
+		log_err("Failed to malloc cmd for setting up lo");
+		remove_netns(name);
+		return -1;
+	}
+
+	r = system(cmd);
+	free(cmd);
+
+	return r;
+}
+
 struct nstoken {
 	int orig_netns_fd;
 };