[RFC bpf-next 20/23] selftests/bpf: Check VLAN tag and proto in xdp_metadata

Larysa Zaremba
2023-08-24T19:34:39Z

Verify, whether VLAN tag and proto are set correctly.

To simulate "stripped" VLAN tag on veth, send test packet from VLAN
interface.

Also, add TO_STR() macro for convenience.

Signed-off-by: Larysa Zaremba <larysa.zaremba@intel.com>
---
.../selftests/bpf/prog_tests/xdp_metadata.c | 21 +++++++++++++++++--
.../selftests/bpf/progs/xdp_metadata.c | 5 +++++
tools/testing/selftests/bpf/testing_helpers.h | 3 +++
3 files changed, 27 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/bpf/prog_tests/xdp_metadata.c b/tools/testing/selftests/bpf/prog_tests/xdp_metadata.c
index 1877e5c6d6c7..61e1b073a4b2 100644
--- a/tools/testing/selftests/bpf/prog_tests/xdp_metadata.c
+++ b/tools/testing/selftests/bpf/prog_tests/xdp_metadata.c
@@ -38,7 +38,14 @@
#define TX_MAC "00:00:00:00:00:01"
#define RX_MAC "00:00:00:00:00:02"

+#define VLAN_ID 59
+#define VLAN_PROTO "802.1Q"
+#define VLAN_PID htons(ETH_P_8021Q)
+#define TX_NAME_VLAN TX_NAME "." TO_STR(VLAN_ID)
+#define RX_NAME_VLAN RX_NAME "." TO_STR(VLAN_ID)
+
#define XDP_RSS_TYPE_L4 BIT(3)
+#define VLAN_VID_MASK 0xfff

struct xsk {
void *umem_area;
@@ -215,6 +222,12 @@ static int verify_xsk_metadata(struct xsk *xsk)
if (!ASSERT_NEQ(meta->rx_hash_type & XDP_RSS_TYPE_L4, 0, "rx_hash_type"))
return -1;

+ if (!ASSERT_EQ(meta->rx_vlan_tci & VLAN_VID_MASK, VLAN_ID, "rx_vlan_tci"))
+ return -1;
+
+ if (!ASSERT_EQ(meta->rx_vlan_proto, VLAN_PID, "rx_vlan_proto"))
+ return -1;
+
xsk_ring_cons__release(&xsk->rx, 1);
refill_rx(xsk, comp_addr);

@@ -248,10 +261,14 @@ void test_xdp_metadata(void)

SYS(out, "ip link set dev " TX_NAME " address " TX_MAC);
SYS(out, "ip link set dev " TX_NAME " up");
- SYS(out, "ip addr add " TX_ADDR "/" PREFIX_LEN " dev " TX_NAME);
+
+ SYS(out, "ip link add link " TX_NAME " " TX_NAME_VLAN
+ " type vlan proto " VLAN_PROTO " id " TO_STR(VLAN_ID));
+ SYS(out, "ip link set dev " TX_NAME_VLAN " up");
+ SYS(out, "ip addr add " TX_ADDR "/" PREFIX_LEN " dev " TX_NAME_VLAN);

/* Avoid ARP calls */
- SYS(out, "ip -4 neigh add " RX_ADDR " lladdr " RX_MAC " dev " TX_NAME);
+ SYS(out, "ip -4 neigh add " RX_ADDR " lladdr " RX_MAC " dev " TX_NAME_VLAN);
close_netns(tok);

tok = open_netns(RX_NETNS_NAME);
diff --git a/tools/testing/selftests/bpf/progs/xdp_metadata.c b/tools/testing/selftests/bpf/progs/xdp_metadata.c
index d151d406a123..f3db5cef4726 100644
--- a/tools/testing/selftests/bpf/progs/xdp_metadata.c
+++ b/tools/testing/selftests/bpf/progs/xdp_metadata.c
@@ -23,6 +23,9 @@ extern int bpf_xdp_metadata_rx_timestamp(const struct xdp_md *ctx,
__u64 *timestamp) __ksym;
extern int bpf_xdp_metadata_rx_hash(const struct xdp_md *ctx, __u32 *hash,
enum xdp_rss_hash_type *rss_type) __ksym;
+extern int bpf_xdp_metadata_rx_vlan_tag(const struct xdp_md *ctx,
+ __u16 *vlan_tci,
+ __be16 *vlan_proto) __ksym;

SEC("xdp")
int rx(struct xdp_md *ctx)
@@ -57,6 +60,8 @@ int rx(struct xdp_md *ctx)
meta->rx_timestamp = 1;

bpf_xdp_metadata_rx_hash(ctx, &meta->rx_hash, &meta->rx_hash_type);
+ bpf_xdp_metadata_rx_vlan_tag(ctx, &meta->rx_vlan_tci,
+ &meta->rx_vlan_proto);

return bpf_redirect_map(&xsk, ctx->rx_queue_index, XDP_PASS);
}
diff --git a/tools/testing/selftests/bpf/testing_helpers.h b/tools/testing/selftests/bpf/testing_helpers.h
index 5b7a55136741..35284faff4f2 100644
--- a/tools/testing/selftests/bpf/testing_helpers.h
+++ b/tools/testing/selftests/bpf/testing_helpers.h
@@ -9,6 +9,9 @@
#include <bpf/libbpf.h>
#include <time.h>

+#define __TO_STR(x) #x
+#define TO_STR(x) __TO_STR(x)
+
int parse_num_list(const char *s, bool **set, int *set_len);
__u32 link_info_prog_id(const struct bpf_link *link, struct bpf_link_info *info);
int bpf_prog_test_load(const char *file, enum bpf_prog_type type,
--
2.41.0