blob: 9390e02442595a39ddfda628b398a91b5b78eede [file] [log] [blame]
#include <linux/bpf.h>
#include "bpf_helpers.h"
#include "bpf_endian.h"
int _version SEC("version") = 1;
SEC("sk_skb1")
int bpf_prog1(struct __sk_buff *skb)
{
void *data_end = (void *)(long) skb->data_end;
void *data = (void *)(long) skb->data;
__u32 lport = skb->local_port;
__u32 rport = skb->remote_port;
__u8 *d = data;
__u32 len = (__u32) data_end - (__u32) data;
int err;
if (data + 10 > data_end) {
err = bpf_skb_pull_data(skb, 10);
if (err)
return SK_DROP;
data_end = (void *)(long)skb->data_end;
data = (void *)(long)skb->data;
if (data + 10 > data_end)
return SK_DROP;
}
/* This write/read is a bit pointless but tests the verifier and
* strparser handler for read/write pkt data and access into sk
* fields.
*/
d = data;
d[7] = 1;
return skb->len;
}
char _license[] SEC("license") = "GPL";