1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Copyright (c) 2017 Facebook
3 */
4 #include <stddef.h>
5 #include <string.h>
6 #include <linux/bpf.h>
7 #include <linux/pkt_cls.h>
8 #include <bpf/bpf_helpers.h>
9
10 #if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
11 #define TEST_FIELD(TYPE, FIELD, MASK) \
12 { \
13 TYPE tmp = *(volatile TYPE *)&skb->FIELD; \
14 if (tmp != ((*(volatile __u32 *)&skb->FIELD) & MASK)) \
15 return TC_ACT_SHOT; \
16 }
17 #else
18 #define TEST_FIELD_OFFSET(a, b) ((sizeof(a) - sizeof(b)) / sizeof(b))
19 #define TEST_FIELD(TYPE, FIELD, MASK) \
20 { \
21 TYPE tmp = *((volatile TYPE *)&skb->FIELD + \
22 TEST_FIELD_OFFSET(skb->FIELD, TYPE)); \
23 if (tmp != ((*(volatile __u32 *)&skb->FIELD) & MASK)) \
24 return TC_ACT_SHOT; \
25 }
26 #endif
27
28 SEC("tc")
test_pkt_md_access(struct __sk_buff * skb)29 int test_pkt_md_access(struct __sk_buff *skb)
30 {
31 TEST_FIELD(__u8, len, 0xFF);
32 TEST_FIELD(__u16, len, 0xFFFF);
33 TEST_FIELD(__u32, len, 0xFFFFFFFF);
34 TEST_FIELD(__u16, protocol, 0xFFFF);
35 TEST_FIELD(__u32, protocol, 0xFFFFFFFF);
36 TEST_FIELD(__u8, hash, 0xFF);
37 TEST_FIELD(__u16, hash, 0xFFFF);
38 TEST_FIELD(__u32, hash, 0xFFFFFFFF);
39
40 return TC_ACT_OK;
41 }
42