tools/testing/selftests/bpf/sockmap_parse_prog.c

   1 #include <linux/bpf.h>
   2 #include "bpf_helpers.h"
   3 #include "bpf_util.h"
   4 #include "bpf_endian.h"
   5
   6 int _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
  15 SEC("sk_skb1")
  16 int 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
  33         bpf_printk("parse: data[0] = (%u): local_port %i remote %i\n",
  34                    d[0], lport, bpf_ntohl(rport));
  35         return skb->len;
  36 }
  37
  38 char _license[] SEC("license") = "GPL";