bpf: add selftest for tcpbpf

Added a selftest for tcpbpf (sock_ops) that checks that the appropriate
callbacks occured and that it can access tcp_sock fields and that their
values are correct.

Run with command: ./test_tcpbpf_user
Adding the flag "-d" will show why it did not pass.

Signed-off-by: Lawrence Brakmo <brakmo@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

1 files changed, 118 insertions, 0 deletions

diff --git a/tools/testing/selftests/bpf/test_tcpbpf_kern.c b/tools/testing/selftests/bpf/test_tcpbpf_kern.c
new file mode 100644
index 000000000000..66bf71541903
--- /dev/null
+++ b/tools/testing/selftests/bpf/test_tcpbpf_kern.c
@@ -0,0 +1,118 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <stddef.h>
+#include <string.h>
+#include <linux/bpf.h>
+#include <linux/if_ether.h>
+#include <linux/if_packet.h>
+#include <linux/ip.h>
+#include <linux/in6.h>
+#include <linux/types.h>
+#include <linux/socket.h>
+#include <linux/tcp.h>
+#include <netinet/in.h>
+#include "bpf_helpers.h"
+#include "bpf_endian.h"
+#include "test_tcpbpf.h"
+
+struct bpf_map_def SEC("maps") global_map = {
+	.type = BPF_MAP_TYPE_ARRAY,
+	.key_size = sizeof(__u32),
+	.value_size = sizeof(struct tcpbpf_globals),
+	.max_entries = 2,
+};
+
+static inline void update_event_map(int event)
+{
+	__u32 key = 0;
+	struct tcpbpf_globals g, *gp;
+
+	gp = bpf_map_lookup_elem(&global_map, &key);
+	if (gp == NULL) {
+		struct tcpbpf_globals g = {0};
+
+		g.event_map |= (1 << event);
+		bpf_map_update_elem(&global_map, &key, &g,
+			    BPF_ANY);
+	} else {
+		g = *gp;
+		g.event_map |= (1 << event);
+		bpf_map_update_elem(&global_map, &key, &g,
+			    BPF_ANY);
+	}
+}
+
+int _version SEC("version") = 1;
+
+SEC("sockops")
+int bpf_testcb(struct bpf_sock_ops *skops)
+{
+	int rv = -1;
+	int bad_call_rv = 0;
+	int good_call_rv = 0;
+	int op;
+	int v = 0;
+
+	op = (int) skops->op;
+
+	update_event_map(op);
+
+	switch (op) {
+	case BPF_SOCK_OPS_ACTIVE_ESTABLISHED_CB:
+		/* Test failure to set largest cb flag (assumes not defined) */
+		bad_call_rv = bpf_sock_ops_cb_flags_set(skops, 0x80);
+		/* Set callback */
+		good_call_rv = bpf_sock_ops_cb_flags_set(skops,
+						 BPF_SOCK_OPS_STATE_CB_FLAG);
+		/* Update results */
+		{
+			__u32 key = 0;
+			struct tcpbpf_globals g, *gp;
+
+			gp = bpf_map_lookup_elem(&global_map, &key);
+			if (!gp)
+				break;
+			g = *gp;
+			g.bad_cb_test_rv = bad_call_rv;
+			g.good_cb_test_rv = good_call_rv;
+			bpf_map_update_elem(&global_map, &key, &g,
+					    BPF_ANY);
+		}
+		break;
+	case BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB:
+		/* Set callback */
+//		good_call_rv = bpf_sock_ops_cb_flags_set(skops,
+//						 BPF_SOCK_OPS_STATE_CB_FLAG);
+		skops->sk_txhash = 0x12345f;
+		v = 0xff;
+		rv = bpf_setsockopt(skops, SOL_IPV6, IPV6_TCLASS, &v,
+				    sizeof(v));
+		break;
+	case BPF_SOCK_OPS_RTO_CB:
+		break;
+	case BPF_SOCK_OPS_RETRANS_CB:
+		break;
+	case BPF_SOCK_OPS_STATE_CB:
+		if (skops->args[1] == BPF_TCP_CLOSE) {
+			__u32 key = 0;
+			struct tcpbpf_globals g, *gp;
+
+			gp = bpf_map_lookup_elem(&global_map, &key);
+			if (!gp)
+				break;
+			g = *gp;
+			g.total_retrans = skops->total_retrans;
+			g.data_segs_in = skops->data_segs_in;
+			g.data_segs_out = skops->data_segs_out;
+			g.bytes_received = skops->bytes_received;
+			g.bytes_acked = skops->bytes_acked;
+			bpf_map_update_elem(&global_map, &key, &g,
+					    BPF_ANY);
+		}
+		break;
+	default:
+		rv = -1;
+	}
+	skops->reply = rv;
+	return 1;
+}
+char _license[] SEC("license") = "GPL";