1#include <linux/bpf.h> 2#include "bpf_helpers.h" 3#include "bpf_util.h" 4#include "bpf_endian.h" 5 6int _version SEC("version") = 1; 7 8#define bpf_printk(fmt, ...) \ 9({ \ 10 char ____fmt[] = fmt; \ 11 bpf_trace_printk(____fmt, sizeof(____fmt), \ 12 ##__VA_ARGS__); \ 13}) 14 15SEC("sk_skb1") 16int bpf_prog1(struct __sk_buff *skb) 17{ 18 void *data_end = (void *)(long) skb->data_end; 19 void *data = (void *)(long) skb->data; 20 __u32 lport = skb->local_port; 21 __u32 rport = skb->remote_port; 22 __u8 *d = data; 23 24 if (data + 10 > data_end) 25 return skb->len; 26 27 /* This write/read is a bit pointless but tests the verifier and 28 * strparser handler for read/write pkt data and access into sk 29 * fields. 30 */ 31 d[7] = 1; 32 return skb->len; 33} 34 35char _license[] SEC("license") = "GPL"; 36