1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _NF_REJECT_H
3#define _NF_REJECT_H
4
5#include <linux/types.h>
6#include <uapi/linux/in.h>
7
8static inline bool nf_reject_verify_csum(struct sk_buff *skb, int dataoff,
9 __u8 proto)
10{
11 /* Skip protocols that don't use 16-bit one's complement checksum
12 * of the entire payload.
13 */
14 switch (proto) {
15 /* Protocols with optional checksums. */
16 case IPPROTO_UDP: {
17 const struct udphdr *udp_hdr;
18 struct udphdr _udp_hdr;
19
20 udp_hdr = skb_header_pointer(skb, offset: dataoff,
21 len: sizeof(_udp_hdr),
22 buffer: &_udp_hdr);
23 if (!udp_hdr || udp_hdr->check)
24 return true;
25
26 return false;
27 }
28 case IPPROTO_GRE:
29
30 /* Protocols with other integrity checks. */
31 case IPPROTO_AH:
32 case IPPROTO_ESP:
33 case IPPROTO_SCTP:
34
35 /* Protocols with partial checksums. */
36 case IPPROTO_UDPLITE:
37 return false;
38 }
39 return true;
40}
41
42#endif /* _NF_REJECT_H */
43