selftest/bpf: Test batching and bpf_(get|set)sockopt in bpf unix iter.

This patch adds a test for the batching and bpf_(get|set)sockopt in bpf
unix iter.

It does the following.

  1. Creates an abstract UNIX domain socket
  2. Call bpf_setsockopt()
  3. Call bpf_getsockopt() and save the value
  4. Call setsockopt()
  5. Call getsockopt() and save the value
  6. Compare the saved values

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp>
Link: https://lore.kernel.org/r/20220113002849.4384-5-kuniyu@amazon.co.jp
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

1 files changed, 60 insertions, 0 deletions

diff --git a/tools/testing/selftests/bpf/progs/bpf_iter_setsockopt_unix.c b/tools/testing/selftests/bpf/progs/bpf_iter_setsockopt_unix.c
new file mode 100644
index 000000000000..eafc877ea460
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/bpf_iter_setsockopt_unix.c
@@ -0,0 +1,60 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright Amazon.com Inc. or its affiliates. */
+#include "bpf_iter.h"
+#include "bpf_tracing_net.h"
+#include <bpf/bpf_helpers.h>
+#include <limits.h>
+
+#define AUTOBIND_LEN 6
+char sun_path[AUTOBIND_LEN];
+
+#define NR_CASES 5
+int sndbuf_setsockopt[NR_CASES] = {-1, 0, 8192, INT_MAX / 2, INT_MAX};
+int sndbuf_getsockopt[NR_CASES] = {-1, -1, -1, -1, -1};
+int sndbuf_getsockopt_expected[NR_CASES];
+
+static inline int cmpname(struct unix_sock *unix_sk)
+{
+	int i;
+
+	for (i = 0; i < AUTOBIND_LEN; i++) {
+		if (unix_sk->addr->name->sun_path[i] != sun_path[i])
+			return -1;
+	}
+
+	return 0;
+}
+
+SEC("iter/unix")
+int change_sndbuf(struct bpf_iter__unix *ctx)
+{
+	struct unix_sock *unix_sk = ctx->unix_sk;
+	int i, err;
+
+	if (!unix_sk || !unix_sk->addr)
+		return 0;
+
+	if (unix_sk->addr->name->sun_path[0])
+		return 0;
+
+	if (cmpname(unix_sk))
+		return 0;
+
+	for (i = 0; i < NR_CASES; i++) {
+		err = bpf_setsockopt(unix_sk, SOL_SOCKET, SO_SNDBUF,
+				     &sndbuf_setsockopt[i],
+				     sizeof(sndbuf_setsockopt[i]));
+		if (err)
+			break;
+
+		err = bpf_getsockopt(unix_sk, SOL_SOCKET, SO_SNDBUF,
+				     &sndbuf_getsockopt[i],
+				     sizeof(sndbuf_getsockopt[i]));
+		if (err)
+			break;
+	}
+
+	return 0;
+}
+
+char _license[] SEC("license") = "GPL";