From 7ba4f1607bd6f2af7884a1e7b360bff666c85c3e Mon Sep 17 00:00:00 2001
From: yunwei37 <1067852565@qq.com>
Date: Fri, 19 May 2023 14:32:55 +0000
Subject: [PATCH] =?UTF-8?q?Deploying=20to=20gh-pages=20from=20@=20eunomia-?=
 =?UTF-8?q?bpf/bpf-developer-tutorial@d57704dd8b130bb53a7d6e243f8aad43585e?=
 =?UTF-8?q?c3bc=20=F0=9F=9A=80?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 21-xdp/.gitignore | 10 ++++++++++
 21-xdp/xdp.bpf.c  | 17 +++++++++++++++++
 2 files changed, 27 insertions(+)
 create mode 100644 21-xdp/.gitignore
 create mode 100644 21-xdp/xdp.bpf.c

diff --git a/21-xdp/.gitignore b/21-xdp/.gitignore
new file mode 100644
index 0000000..bbee7c8
--- /dev/null
+++ b/21-xdp/.gitignore
@@ -0,0 +1,10 @@
+.vscode
+package.json
+*.wasm
+ewasm-skel.h
+ecli
+ewasm
+*.o
+*.skel.json
+*.skel.yaml
+package.yaml
diff --git a/21-xdp/xdp.bpf.c b/21-xdp/xdp.bpf.c
new file mode 100644
index 0000000..a27e475
--- /dev/null
+++ b/21-xdp/xdp.bpf.c
@@ -0,0 +1,17 @@
+#include "vmlinux.h"
+#include <bpf/bpf_helpers.h>
+
+/// @ifindex 1
+/// @flags 0
+/// @xdpopts {"old_prog_fd":0}
+SEC("xdp")
+int xdp_pass(struct xdp_md* ctx) {
+    void* data = (void*)(long)ctx->data;
+    void* data_end = (void*)(long)ctx->data_end;
+    int pkt_sz = data_end - data;
+
+    bpf_printk("packet size is %d", pkt_sz);
+    return XDP_PASS;
+}
+
+char __license[] SEC("license") = "GPL";
\ No newline at end of file