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#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";
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