#include <linux/bpf.h> #include "bpf_helpers.h" #include "bpf_util.h" #include "bpf_endian.h" int _version SEC("version") = 1; #define bpf_printk(fmt, ...) \ ({ \ char ____fmt[] = fmt; \ bpf_trace_printk(____fmt, sizeof(____fmt), \ ##__VA_ARGS__); \ }) SEC("sk_msg1") int bpf_prog1(struct sk_msg_md *msg) { void *data_end = (void *)(long) msg->data_end; void *data = (void *)(long) msg->data; char *d; if (data + 8 > data_end) return SK_DROP; bpf_printk("data length %i\n", (__u64)msg->data_end - (__u64)msg->data); d = (char *)data; bpf_printk("hello sendmsg hook %i %i\n", d[0], d[1]); return SK_PASS; } char _license[] SEC("license") = "GPL";