1 files changed, 53 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/test_xdp_meta.c b/tools/testing/selftests/bpf/progs/test_xdp_meta.c
new file mode 100644
index 000000000..a7c4a7d49
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/test_xdp_meta.c
@@ -0,0 +1,53 @@
+#include <linux/bpf.h>
+#include <linux/if_ether.h>
+#include <linux/pkt_cls.h>
+
+#include <bpf/bpf_helpers.h>
+
+#define __round_mask(x, y) ((__typeof__(x))((y) - 1))
+#define round_up(x, y) ((((x) - 1) | __round_mask(x, y)) + 1)
+#define ctx_ptr(ctx, mem) (void *)(unsigned long)ctx->mem
+
+SEC("t")
+int ing_cls(struct __sk_buff *ctx)
+{
+	__u8 *data, *data_meta, *data_end;
+	__u32 diff = 0;
+
+	data_meta = ctx_ptr(ctx, data_meta);
+	data_end  = ctx_ptr(ctx, data_end);
+	data      = ctx_ptr(ctx, data);
+
+	if (data + ETH_ALEN > data_end ||
+	    data_meta + round_up(ETH_ALEN, 4) > data)
+		return TC_ACT_SHOT;
+
+	diff |= ((__u32 *)data_meta)[0] ^ ((__u32 *)data)[0];
+	diff |= ((__u16 *)data_meta)[2] ^ ((__u16 *)data)[2];
+
+	return diff ? TC_ACT_SHOT : TC_ACT_OK;
+}
+
+SEC("x")
+int ing_xdp(struct xdp_md *ctx)
+{
+	__u8 *data, *data_meta, *data_end;
+	int ret;
+
+	ret = bpf_xdp_adjust_meta(ctx, -round_up(ETH_ALEN, 4));
+	if (ret < 0)
+		return XDP_DROP;
+
+	data_meta = ctx_ptr(ctx, data_meta);
+	data_end  = ctx_ptr(ctx, data_end);
+	data      = ctx_ptr(ctx, data);
+
+	if (data + ETH_ALEN > data_end ||
+	    data_meta + round_up(ETH_ALEN, 4) > data)
+		return XDP_DROP;
+
+	__builtin_memcpy(data_meta, data, ETH_ALEN);
+	return XDP_PASS;
+}
+
+char _license[] SEC("license") = "GPL";