| 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 | |
| 8 | static 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 | case IPPROTO_DCCP: |
| 38 | return false; |
| 39 | } |
| 40 | return true; |
| 41 | } |
| 42 | |
| 43 | #endif /* _NF_REJECT_H */ |
| 44 |