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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";
|
|
